Is integrated graphics supported? #9

darky · 2017-11-10T21:27:30Z

Can GVT give me access to integrated AMD gpu controller via guest OS?

Hartmon8 · 2017-11-13T14:30:49Z

No，GVT support Intel GPU only（broadwell or later）

darky · 2017-11-13T14:53:44Z

Thanks

Thomas reported that 'perf buildid-list' gets a SEGFAULT due to NULL pointer deref when he ran it on a data with namespace events. It was because the buildid_id__mark_dso_hit_ops lacks the namespace event handler and perf_too__fill_default() didn't set it. Program received signal SIGSEGV, Segmentation fault. 0x0000000000000000 in ?? () Missing separate debuginfos, use: dnf debuginfo-install audit-libs-2.7.7-1.fc25.s390x bzip2-libs-1.0.6-21.fc25.s390x elfutils-libelf-0.169-1.fc25.s390x +elfutils-libs-0.169-1.fc25.s390x libcap-ng-0.7.8-1.fc25.s390x numactl-libs-2.0.11-2.ibm.fc25.s390x openssl-libs-1.1.0e-1.1.ibm.fc25.s390x perl-libs-5.24.1-386.fc25.s390x +python-libs-2.7.13-2.fc25.s390x slang-2.3.0-7.fc25.s390x xz-libs-5.2.3-2.fc25.s390x zlib-1.2.8-10.fc25.s390x (gdb) where #0 0x0000000000000000 in ?? () #1 0x00000000010fad6a in machines__deliver_event (machines=<optimized out>, machines@entry=0x2c6fd18, evlist=<optimized out>, event=event@entry=0x3fffdf00470, sample=0x3ffffffe880, sample@entry=0x3ffffffe888, tool=tool@entry=0x1312968 <build_id.mark_dso_hit_ops>, file_offset=1136) at util/session.c:1287 #2 0x00000000010fbf4e in perf_session__deliver_event (file_offset=1136, tool=0x1312968 <build_id.mark_dso_hit_ops>, sample=0x3ffffffe888, event=0x3fffdf00470, session=0x2c6fc30) at util/session.c:1340 #3 perf_session__process_event (session=0x2c6fc30, session@entry=0x0, event=event@entry=0x3fffdf00470, file_offset=file_offset@entry=1136) at util/session.c:1522 #4 0x00000000010fddde in __perf_session__process_events (file_size=11880, data_size=<optimized out>, data_offset=<optimized out>, session=0x0) at util/session.c:1899 #5 perf_session__process_events (session=0x0, session@entry=0x2c6fc30) at util/session.c:1953 #6 0x000000000103b2ac in perf_session__list_build_ids (with_hits=<optimized out>, force=<optimized out>) at builtin-buildid-list.c:83 #7 cmd_buildid_list (argc=<optimized out>, argv=<optimized out>) at builtin-buildid-list.c:115 #8 0x00000000010a026c in run_builtin (p=0x1311f78 <commands+24>, argc=argc@entry=2, argv=argv@entry=0x3fffffff3c0) at perf.c:296 #9 0x000000000102bc00 in handle_internal_command (argv=<optimized out>, argc=2) at perf.c:348 #10 run_argv (argcp=<synthetic pointer>, argv=<synthetic pointer>) at perf.c:392 #11 main (argc=<optimized out>, argv=0x3fffffff3c0) at perf.c:536 (gdb) Fix it by adding a stub event handler for namespace event. Committer testing: Further clarifying, plain using 'perf buildid-list' will not end up in a SEGFAULT when processing a perf.data file with namespace info: # perf record -a --namespaces sleep 1 [ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 2.024 MB perf.data (1058 samples) ] # perf buildid-list | wc -l 38 # perf buildid-list | head -5 e2a171c7b905826fc8494f0711ba76ab6abbd604 /lib/modules/4.14.0-rc3+/build/vmlinux 874840a02d8f8a31cedd605d0b8653145472ced3 /lib/modules/4.14.0-rc3+/kernel/arch/x86/kvm/kvm-intel.ko ea7223776730cd8a22f320040aae4d54312984bc /lib/modules/4.14.0-rc3+/kernel/drivers/gpu/drm/i915/i915.ko 5961535e6732a8edb7f22b3f148bb2fa2e0be4b9 /lib/modules/4.14.0-rc3+/kernel/drivers/gpu/drm/drm.ko f045f54aa78cf1931cc893f78b6cbc52c72a8cb1 /usr/lib64/libc-2.25.so # It is only when one asks for checking what of those entries actually had samples, i.e. when we use either -H or --with-hits, that we will process all the PERF_RECORD_ events, and since tools/perf/builtin-buildid-list.c neither explicitely set a perf_tool.namespaces() callback nor the default stub was set that we end up, when processing a PERF_RECORD_NAMESPACE record, causing a SEGFAULT: # perf buildid-list -H Segmentation fault (core dumped) ^C # Reported-and-Tested-by: Thomas-Mich Richter <tmricht@linux.vnet.ibm.com> Signed-off-by: Namhyung Kim <namhyung@kernel.org> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Hari Bathini <hbathini@linux.vnet.ibm.com> Cc: Hendrik Brueckner <brueckner@linux.vnet.ibm.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas-Mich Richter <tmricht@linux.vnet.ibm.com> Fixes: f3b3614 ("perf tools: Add PERF_RECORD_NAMESPACES to include namespaces related info") Link: http://lkml.kernel.org/r/20171017132900.11043-1-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

The locking order of vlan_rwsem (LOCK A) and then rtnl (LOCK B), contradicts other flows such as ipoib_open possibly causing a deadlock. To prevent this deadlock heavy flush is called with RTNL locked and only then tries to acquire vlan_rwsem. This deadlock is possible only when there are child interfaces. [ 140.941758] ====================================================== [ 140.946276] WARNING: possible circular locking dependency detected [ 140.950950] 4.15.0-rc1+ #9 Tainted: G O [ 140.954797] ------------------------------------------------------ [ 140.959424] kworker/u32:1/146 is trying to acquire lock: [ 140.963450] (rtnl_mutex){+.+.}, at: [<ffffffffc083516a>] __ipoib_ib_dev_flush+0x2da/0x4e0 [ib_ipoib] [ 140.970006] but task is already holding lock: [ 140.975141] (&priv->vlan_rwsem){++++}, at: [<ffffffffc0834ee1>] __ipoib_ib_dev_flush+0x51/0x4e0 [ib_ipoib] [ 140.982105] which lock already depends on the new lock. [ 140.990023] the existing dependency chain (in reverse order) is: [ 140.998650] -> #1 (&priv->vlan_rwsem){++++}: [ 141.005276] down_read+0x4d/0xb0 [ 141.009560] ipoib_open+0xad/0x120 [ib_ipoib] [ 141.014400] __dev_open+0xcb/0x140 [ 141.017919] __dev_change_flags+0x1a4/0x1e0 [ 141.022133] dev_change_flags+0x23/0x60 [ 141.025695] devinet_ioctl+0x704/0x7d0 [ 141.029156] sock_do_ioctl+0x20/0x50 [ 141.032526] sock_ioctl+0x221/0x300 [ 141.036079] do_vfs_ioctl+0xa6/0x6d0 [ 141.039656] SyS_ioctl+0x74/0x80 [ 141.042811] entry_SYSCALL_64_fastpath+0x1f/0x96 [ 141.046891] -> #0 (rtnl_mutex){+.+.}: [ 141.051701] lock_acquire+0xd4/0x220 [ 141.055212] __mutex_lock+0x88/0x970 [ 141.058631] __ipoib_ib_dev_flush+0x2da/0x4e0 [ib_ipoib] [ 141.063160] __ipoib_ib_dev_flush+0x71/0x4e0 [ib_ipoib] [ 141.067648] process_one_work+0x1f5/0x610 [ 141.071429] worker_thread+0x4a/0x3f0 [ 141.074890] kthread+0x141/0x180 [ 141.078085] ret_from_fork+0x24/0x30 [ 141.081559] other info that might help us debug this: [ 141.088967] Possible unsafe locking scenario: [ 141.094280] CPU0 CPU1 [ 141.097953] ---- ---- [ 141.101640] lock(&priv->vlan_rwsem); [ 141.104771] lock(rtnl_mutex); [ 141.109207] lock(&priv->vlan_rwsem); [ 141.114032] lock(rtnl_mutex); [ 141.116800] *** DEADLOCK *** Fixes: b4b678b ("IB/ipoib: Grab rtnl lock on heavy flush when calling ndo_open/stop") Signed-off-by: Alex Vesker <valex@mellanox.com> Signed-off-by: Leon Romanovsky <leon@kernel.org> Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

Scenario: 1. Port down and do fail over 2. Ap do rds_bind syscall PID: 47039 TASK: ffff89887e2fe640 CPU: 47 COMMAND: "kworker/u:6" #0 [ffff898e35f159f0] machine_kexec at ffffffff8103abf9 #1 [ffff898e35f15a60] crash_kexec at ffffffff810b96e3 #2 [ffff898e35f15b30] oops_end at ffffffff8150f518 #3 [ffff898e35f15b60] no_context at ffffffff8104854c #4 [ffff898e35f15ba0] __bad_area_nosemaphore at ffffffff81048675 #5 [ffff898e35f15bf0] bad_area_nosemaphore at ffffffff810487d3 #6 [ffff898e35f15c00] do_page_fault at ffffffff815120b8 #7 [ffff898e35f15d10] page_fault at ffffffff8150ea95 [exception RIP: unknown or invalid address] RIP: 0000000000000000 RSP: ffff898e35f15dc8 RFLAGS: 00010282 RAX: 00000000fffffffe RBX: ffff889b77f6fc00 RCX:ffffffff81c99d88 RDX: 0000000000000000 RSI: ffff896019ee08e8 RDI:ffff889b77f6fc00 RBP: ffff898e35f15df0 R8: ffff896019ee08c8 R9:0000000000000000 R10: 0000000000000400 R11: 0000000000000000 R12:ffff896019ee08c0 R13: ffff889b77f6fe68 R14: ffffffff81c99d80 R15: ffffffffa022a1e0 ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0018 #8 [ffff898e35f15dc8] cma_ndev_work_handler at ffffffffa022a228 [rdma_cm] #9 [ffff898e35f15df8] process_one_work at ffffffff8108a7c6 #10 [ffff898e35f15e58] worker_thread at ffffffff8108bda0 #11 [ffff898e35f15ee8] kthread at ffffffff81090fe6 PID: 45659 TASK: ffff880d313d2500 CPU: 31 COMMAND: "oracle_45659_ap" #0 [ffff881024ccfc98] __schedule at ffffffff8150bac4 #1 [ffff881024ccfd40] schedule at ffffffff8150c2cf #2 [ffff881024ccfd50] __mutex_lock_slowpath at ffffffff8150cee7 #3 [ffff881024ccfdc0] mutex_lock at ffffffff8150cdeb #4 [ffff881024ccfde0] rdma_destroy_id at ffffffffa022a027 [rdma_cm] #5 [ffff881024ccfe10] rds_ib_laddr_check at ffffffffa0357857 [rds_rdma] #6 [ffff881024ccfe50] rds_trans_get_preferred at ffffffffa0324c2a [rds] #7 [ffff881024ccfe80] rds_bind at ffffffffa031d690 [rds] #8 [ffff881024ccfeb0] sys_bind at ffffffff8142a670 PID: 45659 PID: 47039 rds_ib_laddr_check /* create id_priv with a null event_handler */ rdma_create_id rdma_bind_addr cma_acquire_dev /* add id_priv to cma_dev->id_list */ cma_attach_to_dev cma_ndev_work_handler /* event_hanlder is null */ id_priv->id.event_handler Signed-off-by: Guanglei Li <guanglei.li@oracle.com> Signed-off-by: Honglei Wang <honglei.wang@oracle.com> Reviewed-by: Junxiao Bi <junxiao.bi@oracle.com> Reviewed-by: Yanjun Zhu <yanjun.zhu@oracle.com> Reviewed-by: Leon Romanovsky <leonro@mellanox.com> Acked-by: Santosh Shilimkar <santosh.shilimkar@oracle.com> Acked-by: Doug Ledford <dledford@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>

It was reported by Sergey Senozhatsky that if THP (Transparent Huge Page) and frontswap (via zswap) are both enabled, when memory goes low so that swap is triggered, segfault and memory corruption will occur in random user space applications as follow, kernel: urxvt[338]: segfault at 20 ip 00007fc08889ae0d sp 00007ffc73a7fc40 error 6 in libc-2.26.so[7fc08881a000+1ae000] #0 0x00007fc08889ae0d _int_malloc (libc.so.6) #1 0x00007fc08889c2f3 malloc (libc.so.6) #2 0x0000560e6004bff7 _Z14rxvt_wcstoutf8PKwi (urxvt) #3 0x0000560e6005e75c n/a (urxvt) #4 0x0000560e6007d9f1 _ZN16rxvt_perl_interp6invokeEP9rxvt_term9hook_typez (urxvt) #5 0x0000560e6003d988 _ZN9rxvt_term9cmd_parseEv (urxvt) #6 0x0000560e60042804 _ZN9rxvt_term6pty_cbERN2ev2ioEi (urxvt) #7 0x0000560e6005c10f _Z17ev_invoke_pendingv (urxvt) #8 0x0000560e6005cb55 ev_run (urxvt) #9 0x0000560e6003b9b9 main (urxvt) #10 0x00007fc08883af4a __libc_start_main (libc.so.6) #11 0x0000560e6003f9da _start (urxvt) After bisection, it was found the first bad commit is bd4c82c ("mm, THP, swap: delay splitting THP after swapped out"). The root cause is as follows: When the pages are written to swap device during swapping out in swap_writepage(), zswap (fontswap) is tried to compress the pages to improve performance. But zswap (frontswap) will treat THP as a normal page, so only the head page is saved. After swapping in, tail pages will not be restored to their original contents, causing memory corruption in the applications. This is fixed by refusing to save page in the frontswap store functions if the page is a THP. So that the THP will be swapped out to swap device. Another choice is to split THP if frontswap is enabled. But it is found that the frontswap enabling isn't flexible. For example, if CONFIG_ZSWAP=y (cannot be module), frontswap will be enabled even if zswap itself isn't enabled. Frontswap has multiple backends, to make it easy for one backend to enable THP support, the THP checking is put in backend frontswap store functions instead of the general interfaces. Link: http://lkml.kernel.org/r/20180209084947.22749-1-ying.huang@intel.com Fixes: bd4c82c ("mm, THP, swap: delay splitting THP after swapped out") Signed-off-by: "Huang, Ying" <ying.huang@intel.com> Reported-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Tested-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Suggested-by: Minchan Kim <minchan@kernel.org> [put THP checking in backend] Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Dan Streetman <ddstreet@ieee.org> Cc: Seth Jennings <sjenning@redhat.com> Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Cc: Shaohua Li <shli@kernel.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Shakeel Butt <shakeelb@google.com> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Juergen Gross <jgross@suse.com> Cc: <stable@vger.kernel.org> [4.14] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

This patch fixes NULL pointer crash due to active timer running for abort IOCB. From crash dump analysis it was discoverd that get_next_timer_interrupt() encountered a corrupted entry on the timer list. #9 [ffff95e1f6f0fd40] page_fault at ffffffff914fe8f8 [exception RIP: get_next_timer_interrupt+440] RIP: ffffffff90ea3088 RSP: ffff95e1f6f0fdf0 RFLAGS: 00010013 RAX: ffff95e1f6451028 RBX: 000218e2389e5f40 RCX: 00000001232ad600 RDX: 0000000000000001 RSI: ffff95e1f6f0fdf0 RDI: 0000000001232ad6 RBP: ffff95e1f6f0fe40 R8: ffff95e1f6451188 R9: 0000000000000001 R10: 0000000000000016 R11: 0000000000000016 R12: 00000001232ad5f6 R13: ffff95e1f6450000 R14: ffff95e1f6f0fdf8 R15: ffff95e1f6f0fe10 ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0018 Looking at the assembly of get_next_timer_interrupt(), address came from %r8 (ffff95e1f6451188) which is pointing to list_head with single entry at ffff95e5ff621178. 0xffffffff90ea307a <get_next_timer_interrupt+426>: mov (%r8),%rdx 0xffffffff90ea307d <get_next_timer_interrupt+429>: cmp %r8,%rdx 0xffffffff90ea3080 <get_next_timer_interrupt+432>: je 0xffffffff90ea30a7 <get_next_timer_interrupt+471> 0xffffffff90ea3082 <get_next_timer_interrupt+434>: nopw 0x0(%rax,%rax,1) 0xffffffff90ea3088 <get_next_timer_interrupt+440>: testb $0x1,0x18(%rdx) crash> rd ffff95e1f6451188 10 ffff95e1f6451188: ffff95e5ff621178 ffff95e5ff621178 x.b.....x.b..... ffff95e1f6451198: ffff95e1f6451198 ffff95e1f6451198 ..E.......E..... ffff95e1f64511a8: ffff95e1f64511a8 ffff95e1f64511a8 ..E.......E..... ffff95e1f64511b8: ffff95e77cf509a0 ffff95e77cf509a0 ...|.......|.... ffff95e1f64511c8: ffff95e1f64511c8 ffff95e1f64511c8 ..E.......E..... crash> rd ffff95e5ff621178 10 ffff95e5ff621178: 0000000000000001 ffff95e15936aa00 ..........6Y.... ffff95e5ff621188: 0000000000000000 00000000ffffffff ................ ffff95e5ff621198: 00000000000000a0 0000000000000010 ................ ffff95e5ff6211a8: ffff95e5ff621198 000000000000000c ..b............. ffff95e5ff6211b8: 00000f5800000000 ffff95e751f8d720 ....X... ..Q.... ffff95e5ff621178 belongs to freed mempool object at ffff95e5ff621080. CACHE NAME OBJSIZE ALLOCATED TOTAL SLABS SSIZE ffff95dc7fd74d00 mnt_cache 384 19785 24948 594 16k SLAB MEMORY NODE TOTAL ALLOCATED FREE ffffdc5dabfd8800 ffff95e5ff620000 1 42 29 13 FREE / [ALLOCATED] ffff95e5ff621080 (cpu 6 cache) Examining the contents of that memory reveals a pointer to a constant string in the driver, "abort\0", which is set by qla24xx_async_abort_cmd(). crash> rd ffffffffc059277c 20 ffffffffc059277c: 6e490074726f6261 0074707572726574 abort.Interrupt. ffffffffc059278c: 00676e696c6c6f50 6920726576697244 Polling.Driver i ffffffffc059279c: 646f6d207325206e 6974736554000a65 n %s mode..Testi ffffffffc05927ac: 636976656420676e 786c252074612065 ng device at %lx ffffffffc05927bc: 6b63656843000a2e 646f727020676e69 ...Checking prod ffffffffc05927cc: 6f20444920746375 0a2e706968632066 uct ID of chip.. ffffffffc05927dc: 5120646e756f4600 204130303232414c .Found QLA2200A ffffffffc05927ec: 43000a2e70696843 20676e696b636568 Chip...Checking ffffffffc05927fc: 65786f626c69616d 6c636e69000a2e73 mailboxes...incl ffffffffc059280c: 756e696c2f656475 616d2d616d642f78 ude/linux/dma-ma crash> struct -ox srb_iocb struct srb_iocb { union { struct {...} logio; struct {...} els_logo; struct {...} tmf; struct {...} fxiocb; struct {...} abt; struct ct_arg ctarg; struct {...} mbx; struct {...} nack; [0x0 ] } u; [0xb8] struct timer_list timer; [0x108] void (*timeout)(void *); } SIZE: 0x110 crash> ! bc ibase=16 obase=10 B8+40 F8 The object is a srb_t, and at offset 0xf8 within that structure (i.e. ffff95e5ff621080 + f8 -> ffff95e5ff621178) is a struct timer_list. Cc: <stable@vger.kernel.org> #4.4+ Fixes: 4440e46 ("[SCSI] qla2xxx: Add IOCB Abort command asynchronous handling.") Signed-off-by: Himanshu Madhani <himanshu.madhani@cavium.com> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

Not only is the context suspect to disappearing, but so is it's timeline. Under a lockless inspection of the requests for debugging from intel_engine_dump(), the context may already have been freed and we have to check before chasing the dangling pointer. [28033.681755] Modules linked in: vgem snd_hda_codec_hdmi snd_hda_codec_realtek snd_hda_codec_generic x86_pkg_temp_thermal intel_powerclamp coretemp snd_hda_intel crct10dif_pclmul crc32_pclmul snd_hda_codec snd_hwdep snd_hda_core ghash_clmulni_intel snd_pcm mei_me mei i915 r8169 mii prime_numbers i2c_hid [28033.681796] CPU: 3 PID: 3058 Comm: gem_exec_schedu Tainted: G U 4.16.0-rc5+ #9 [28033.681804] Hardware name: Acer Aspire E5-575G/Ironman_SK , BIOS V1.12 08/02/2016 [28033.681834] RIP: 0010:print_request+0x2b/0xb0 [i915] [28033.681840] RSP: 0018:ffffc90004afbc18 EFLAGS: 00010202 [28033.681847] RAX: 6b6b6b6b6b6b6b6b RBX: ffff8801921b5a40 RCX: 0000000000000006 [28033.681854] RDX: ffffc90004afbc60 RSI: ffff8801921b5a40 RDI: 0000000000000004 [28033.681861] RBP: ffffc90004afbd80 R08: 0000000000000000 R09: 0000000000000001 [28033.681868] R10: ffffc90004afbbd0 R11: ffffc90004afbc73 R12: ffffc90004afbc60 [28033.681875] R13: ffffc90004afbd80 R14: ffff8801d40ec670 R15: ffff8801921b5a40 [28033.681883] FS: 00007fbba5f6c8c0(0000) GS:ffff8801e8400000(0000) knlGS:0000000000000000 [28033.681891] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [28033.681897] CR2: 00007fbba5f8f000 CR3: 00000001b2efa002 CR4: 00000000003606e0 [28033.681904] Call Trace: [28033.681932] intel_engine_print_registers+0x6a7/0x930 [i915] [28033.681962] intel_engine_dump+0x30d/0x740 [i915] [28033.681971] ? seq_printf+0x3a/0x50 [28033.681995] i915_engine_info+0xb8/0xe0 [i915] [28033.682003] ? drm_get_color_range_name+0x20/0x20 [28033.682010] seq_read+0xe1/0x440 [28033.682018] full_proxy_read+0x51/0x80 [28033.682025] __vfs_read+0x21/0x130 [28033.682031] ? do_sys_open+0x134/0x220 [28033.682037] ? kmem_cache_free+0x177/0x2b0 [28033.682043] vfs_read+0xa1/0x150 [28033.682049] SyS_read+0x40/0xa0 [28033.682055] do_syscall_64+0x6b/0x1b0 [28033.682063] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [28033.682069] RIP: 0033:0x7fbba4655d11 [28033.682074] RSP: 002b:00007ffd8c49da58 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 [28033.682082] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fbba4655d11 [28033.682089] RDX: 000000000000003f RSI: 00005647bfbfc260 RDI: 0000000000000006 [28033.682096] RBP: 000000000000003f R08: 00000000ffffffff R09: 0000000000000000 [28033.682104] R10: 0000000000000000 R11: 0000000000000246 R12: 00005647bfbfc260 [28033.682111] R13: 0000000000000006 R14: 0000000000000000 R15: 00005647bfbfc260 [28033.682119] Code: 41 55 41 54 49 89 d4 55 53 48 89 fd 48 8b 86 c8 00 00 00 48 8b 3d d6 1e 14 e2 48 89 f3 48 2b be a8 02 00 00 48 8b 80 b0 00 00 00 <4c> 8b 68 18 e8 bc 80 02 e1 8b 8b 70 02 00 00 8b b3 28 02 00 00 [28033.682206] RIP: print_request+0x2b/0xb0 [i915] RSP: ffffc90004afbc18 Reported-by: Mika Kuoppala <mika.kuoppala@linux.intel.com> Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com> Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20180314101630.8933-1-chris@chris-wilson.co.uk

…s found If an OVS_ATTR_NESTED attribute type is found while walking through netlink attributes, we call nlattr_set() recursively passing the length table for the following nested attributes, if different from the current one. However, once we're done with those sub-nested attributes, we should continue walking through attributes using the current table, instead of using the one related to the sub-nested attributes. For example, given this sequence: 1 OVS_KEY_ATTR_PRIORITY 2 OVS_KEY_ATTR_TUNNEL 3 OVS_TUNNEL_KEY_ATTR_ID 4 OVS_TUNNEL_KEY_ATTR_IPV4_SRC 5 OVS_TUNNEL_KEY_ATTR_IPV4_DST 6 OVS_TUNNEL_KEY_ATTR_TTL 7 OVS_TUNNEL_KEY_ATTR_TP_SRC 8 OVS_TUNNEL_KEY_ATTR_TP_DST 9 OVS_KEY_ATTR_IN_PORT 10 OVS_KEY_ATTR_SKB_MARK 11 OVS_KEY_ATTR_MPLS we switch to the 'ovs_tunnel_key_lens' table on attribute #3, and we don't switch back to 'ovs_key_lens' while setting attributes #9 to #11 in the sequence. As OVS_KEY_ATTR_MPLS evaluates to 21, and the array size of 'ovs_tunnel_key_lens' is 15, we also get this kind of KASan splat while accessing the wrong table: [ 7654.586496] ================================================================== [ 7654.594573] BUG: KASAN: global-out-of-bounds in nlattr_set+0x164/0xde9 [openvswitch] [ 7654.603214] Read of size 4 at addr ffffffffc169ecf0 by task handler29/87430 [ 7654.610983] [ 7654.612644] CPU: 21 PID: 87430 Comm: handler29 Kdump: loaded Not tainted 3.10.0-866.el7.test.x86_64 #1 [ 7654.623030] Hardware name: Dell Inc. PowerEdge R730/072T6D, BIOS 2.1.7 06/16/2016 [ 7654.631379] Call Trace: [ 7654.634108] [<ffffffffb65a7c50>] dump_stack+0x19/0x1b [ 7654.639843] [<ffffffffb53ff373>] print_address_description+0x33/0x290 [ 7654.647129] [<ffffffffc169b37b>] ? nlattr_set+0x164/0xde9 [openvswitch] [ 7654.654607] [<ffffffffb53ff812>] kasan_report.part.3+0x242/0x330 [ 7654.661406] [<ffffffffb53ff9b4>] __asan_report_load4_noabort+0x34/0x40 [ 7654.668789] [<ffffffffc169b37b>] nlattr_set+0x164/0xde9 [openvswitch] [ 7654.676076] [<ffffffffc167ef68>] ovs_nla_get_match+0x10c8/0x1900 [openvswitch] [ 7654.684234] [<ffffffffb61e9cc8>] ? genl_rcv+0x28/0x40 [ 7654.689968] [<ffffffffb61e7733>] ? netlink_unicast+0x3f3/0x590 [ 7654.696574] [<ffffffffc167dea0>] ? ovs_nla_put_tunnel_info+0xb0/0xb0 [openvswitch] [ 7654.705122] [<ffffffffb4f41b50>] ? unwind_get_return_address+0xb0/0xb0 [ 7654.712503] [<ffffffffb65d9355>] ? system_call_fastpath+0x1c/0x21 [ 7654.719401] [<ffffffffb4f41d79>] ? update_stack_state+0x229/0x370 [ 7654.726298] [<ffffffffb4f41d79>] ? update_stack_state+0x229/0x370 [ 7654.733195] [<ffffffffb53fe4b5>] ? kasan_unpoison_shadow+0x35/0x50 [ 7654.740187] [<ffffffffb53fe62a>] ? kasan_kmalloc+0xaa/0xe0 [ 7654.746406] [<ffffffffb53fec32>] ? kasan_slab_alloc+0x12/0x20 [ 7654.752914] [<ffffffffb53fe711>] ? memset+0x31/0x40 [ 7654.758456] [<ffffffffc165bf92>] ovs_flow_cmd_new+0x2b2/0xf00 [openvswitch] [snip] [ 7655.132484] The buggy address belongs to the variable: [ 7655.138226] ovs_tunnel_key_lens+0xf0/0xffffffffffffd400 [openvswitch] [ 7655.145507] [ 7655.147166] Memory state around the buggy address: [ 7655.152514] ffffffffc169eb80: 00 00 00 00 00 00 00 00 00 00 fa fa fa fa fa fa [ 7655.160585] ffffffffc169ec00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 7655.168644] >ffffffffc169ec80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 fa fa [ 7655.176701] ^ [ 7655.184372] ffffffffc169ed00: fa fa fa fa 00 00 00 00 fa fa fa fa 00 00 00 05 [ 7655.192431] ffffffffc169ed80: fa fa fa fa 00 00 00 00 00 00 00 00 00 00 00 00 [ 7655.200490] ================================================================== Reported-by: Hangbin Liu <liuhangbin@gmail.com> Fixes: 982b527 ("openvswitch: Fix mask generation for nested attributes.") Signed-off-by: Stefano Brivio <sbrivio@redhat.com> Reviewed-by: Sabrina Dubroca <sd@queasysnail.net> Signed-off-by: David S. Miller <davem@davemloft.net>

syzbot caught an infinite recursion in nsh_gso_segment(). Problem here is that we need to make sure the NSH header is of reasonable length. BUG: MAX_LOCK_DEPTH too low! turning off the locking correctness validator. depth: 48 max: 48! 48 locks held by syz-executor0/10189: #0: (ptrval) (rcu_read_lock_bh){....}, at: __dev_queue_xmit+0x30f/0x34c0 net/core/dev.c:3517 #1: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #1: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #2: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #2: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #3: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #3: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #4: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #4: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #5: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #5: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #6: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #6: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #7: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #7: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #8: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #8: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #9: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #9: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #10: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #10: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #11: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #11: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #12: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #12: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #13: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #13: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #14: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #14: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #15: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #15: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #16: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #16: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #17: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #17: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #18: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #18: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #19: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #19: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #20: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #20: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #21: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #21: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #22: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #22: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #23: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #23: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #24: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #24: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #25: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #25: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #26: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #26: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #27: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #27: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #28: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #28: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #29: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #29: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #30: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #30: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #31: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #31: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 dccp_close: ABORT with 65423 bytes unread #32: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #32: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #33: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #33: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #34: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #34: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #35: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #35: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #36: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #36: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #37: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #37: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #38: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #38: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #39: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #39: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #40: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #40: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #41: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #41: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #42: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #42: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #43: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #43: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #44: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #44: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #45: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #45: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #46: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #46: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #47: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #47: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 INFO: lockdep is turned off. CPU: 1 PID: 10189 Comm: syz-executor0 Not tainted 4.17.0-rc2+ #26 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1b9/0x294 lib/dump_stack.c:113 __lock_acquire+0x1788/0x5140 kernel/locking/lockdep.c:3449 lock_acquire+0x1dc/0x520 kernel/locking/lockdep.c:3920 rcu_lock_acquire include/linux/rcupdate.h:246 [inline] rcu_read_lock include/linux/rcupdate.h:632 [inline] skb_mac_gso_segment+0x25b/0x720 net/core/dev.c:2789 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 __skb_gso_segment+0x3bb/0x870 net/core/dev.c:2865 skb_gso_segment include/linux/netdevice.h:4025 [inline] validate_xmit_skb+0x54d/0xd90 net/core/dev.c:3118 validate_xmit_skb_list+0xbf/0x120 net/core/dev.c:3168 sch_direct_xmit+0x354/0x11e0 net/sched/sch_generic.c:312 qdisc_restart net/sched/sch_generic.c:399 [inline] __qdisc_run+0x741/0x1af0 net/sched/sch_generic.c:410 __dev_xmit_skb net/core/dev.c:3243 [inline] __dev_queue_xmit+0x28ea/0x34c0 net/core/dev.c:3551 dev_queue_xmit+0x17/0x20 net/core/dev.c:3616 packet_snd net/packet/af_packet.c:2951 [inline] packet_sendmsg+0x40f8/0x6070 net/packet/af_packet.c:2976 sock_sendmsg_nosec net/socket.c:629 [inline] sock_sendmsg+0xd5/0x120 net/socket.c:639 __sys_sendto+0x3d7/0x670 net/socket.c:1789 __do_sys_sendto net/socket.c:1801 [inline] __se_sys_sendto net/socket.c:1797 [inline] __x64_sys_sendto+0xe1/0x1a0 net/socket.c:1797 do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x49/0xbe Fixes: c411ed8 ("nsh: add GSO support") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Jiri Benc <jbenc@redhat.com> Reported-by: syzbot <syzkaller@googlegroups.com> Acked-by: Jiri Benc <jbenc@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>

platform_domain_notifier contains a variable sized array, which the pm_clk_notify() notifier treats as a NULL terminated array: for (con_id = clknb->con_ids; *con_id; con_id++) pm_clk_add(dev, *con_id); Omitting the initialiser for con_ids means that the array is zero sized, and there is no NULL terminator. This leads to pm_clk_notify() overrunning into what ever structure follows, which may not be NULL. This leads to an oops: Unable to handle kernel NULL pointer dereference at virtual address 0000008c pgd = c0003000 [0000008c] *pgd=80000800004003c, *pmd=00000000c Internal error: Oops: 206 [#1] PREEMPT SMP ARM Modules linked in:c CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.16.0+ #9 Hardware name: Keystone PC is at strlen+0x0/0x34 LR is at kstrdup+0x18/0x54 pc : [<c0623340>] lr : [<c0111d6c>] psr: 20000013 sp : eec73dc0 ip : eed780c0 fp : 00000001 r10: 00000000 r9 : 00000000 r8 : eed71e10 r7 : 0000008c r6 : 0000008c r5 : 014000c0 r4 : c03a6ff4 r3 : c09445d0 r2 : 00000000 r1 : 014000c0 r0 : 0000008c Flags: nzCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user Control: 30c5387d Table: 00003000 DAC: fffffffd Process swapper/0 (pid: 1, stack limit = 0xeec72210) Stack: (0xeec73dc0 to 0xeec74000) ... [<c0623340>] (strlen) from [<c0111d6c>] (kstrdup+0x18/0x54) [<c0111d6c>] (kstrdup) from [<c03a6ff4>] (__pm_clk_add+0x58/0x120) [<c03a6ff4>] (__pm_clk_add) from [<c03a731c>] (pm_clk_notify+0x64/0xa8) [<c03a731c>] (pm_clk_notify) from [<c004614c>] (notifier_call_chain+0x44/0x84) [<c004614c>] (notifier_call_chain) from [<c0046320>] (__blocking_notifier_call_chain+0x48/0x60) [<c0046320>] (__blocking_notifier_call_chain) from [<c0046350>] (blocking_notifier_call_chain+0x18/0x20) [<c0046350>] (blocking_notifier_call_chain) from [<c0390234>] (device_add+0x36c/0x534) [<c0390234>] (device_add) from [<c047fc00>] (of_platform_device_create_pdata+0x70/0xa4) [<c047fc00>] (of_platform_device_create_pdata) from [<c047fea0>] (of_platform_bus_create+0xf0/0x1ec) [<c047fea0>] (of_platform_bus_create) from [<c047fff8>] (of_platform_populate+0x5c/0xac) [<c047fff8>] (of_platform_populate) from [<c08b1f04>] (of_platform_default_populate_init+0x8c/0xa8) [<c08b1f04>] (of_platform_default_populate_init) from [<c000a78c>] (do_one_initcall+0x3c/0x164) [<c000a78c>] (do_one_initcall) from [<c087bd9c>] (kernel_init_freeable+0x10c/0x1d0) [<c087bd9c>] (kernel_init_freeable) from [<c0628db0>] (kernel_init+0x8/0xf0) [<c0628db0>] (kernel_init) from [<c00090d8>] (ret_from_fork+0x14/0x3c) Exception stack(0xeec73fb0 to 0xeec73ff8) 3fa0: 00000000 00000000 00000000 00000000 3fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 3fe0: 00000000 00000000 00000000 00000000 00000013 00000000 Code: e3520000 1afffff7 e12fff1e c0801730 (e5d02000) ---[ end trace cafa8f148e262e80 ]--- Fix this by adding the necessary initialiser. Fixes: fc20ffe ("ARM: keystone: add PM domain support for clock management") Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> Acked-by: Santosh Shilimkar <ssantosh@kernel.org> Signed-off-by: Olof Johansson <olof@lixom.net>

For psr block #9, the vbt description has moved to options [0-3] for TP1,TP2,TP3 Wakeup time from decimal value without any change to vbt structure. Since spec does not mention from which VBT version this change was added to vbt.bsf file, we cannot depend on bdb->version check to change for all the platforms. There is RCR inplace for GOP team to provide the version number to make generic change. Since Kabylake with bdb version 209 is having this change, limiting this change to gen9_bc and version 209+ to unblock google. Tested on skl(bdb version 203,without options) and kabylake(bdb version 209,212) having new options. bspec 20131 v2: (Jani and Rodrigo) move the 165 version check to intel_bios.c v3: Jani Move the abstraction to intel_bios. v4: Jani Rename tp*_wakeup_time to have "us" suffix. For values outside range[0-3],default to max 2500us. Old decimal value was wake up time in multiples of 100us. v5: Jani and Rodrigo Handle option 2 in default condition. Print oustide range value. For negetive values default to 2500us. v6: Jani Handle default first and then fall through for case 2. v7: Rodrigo Apply this change for IS_GEN9_BC and vbt version > 209 v8: Puthik Add new function vbt_psr_to_us. v9: Jani Change to v7 version as it's more readable. DK add comment /*fall through*/ after case2. Cc: Rodrigo Vivi <rodrigo.vivi@intel.com> Cc: Puthikorn Voravootivat <puthik@chromium.org> Cc: Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com> Cc: Jani Nikula <jani.nikula@intel.com> Cc: José Roberto de Souza <jose.souza@intel.com> Signed-off-by: Maulik V Vaghela <maulik.v.vaghela@intel.com> Signed-off-by: Vathsala Nagaraju <vathsala.nagaraju@intel.com> Reviewed-by: Jani Nikula <jani.nikula@intel.com> Signed-off-by: Jani Nikula <jani.nikula@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/1526981243-2745-1-git-send-email-vathsala.nagaraju@intel.com

…ABI!) * Test lookup in /proc/self/fd. "map_files" lookup story showed that lookup is not that simple. * Test that all those symlinks open the same file. Check with (st_dev, st_info). * Test that kernel threads do not have anything in their /proc/*/fd/ directory. Now this is where things get interesting. First, kernel threads aren't pinned by /proc/self or equivalent, thus some "atomicity" is required. Second, ->comm can contain whitespace and ')'. No, they are not escaped. Third, the only reliable way to check if process is kernel thread appears to be field #9 in /proc/*/stat. This field is struct task_struct::flags in decimal! Check is done by testing PF_KTHREAD flags like we do in kernel. PF_KTREAD value is a part of userspace ABI !!! Other methods for determining kernel threadness are not reliable: * RSS can be 0 if everything is swapped, even while reading from /proc/self. * ->total_vm CAN BE ZERO if process is finishing munmap(NULL, whole address space); * /proc/*/maps and similar files can be empty because unmapping everything works. Read returning 0 can't distinguish between kernel thread and such suicide process. Link: http://lkml.kernel.org/r/20180505000414.GA15090@avx2 Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Crash dump shows following instructions crash> bt PID: 0 TASK: ffffffffbe412480 CPU: 0 COMMAND: "swapper/0" #0 [ffff891ee0003868] machine_kexec at ffffffffbd063ef1 #1 [ffff891ee00038c8] __crash_kexec at ffffffffbd12b6f2 #2 [ffff891ee0003998] crash_kexec at ffffffffbd12c84c #3 [ffff891ee00039b8] oops_end at ffffffffbd030f0a #4 [ffff891ee00039e0] no_context at ffffffffbd074643 #5 [ffff891ee0003a40] __bad_area_nosemaphore at ffffffffbd07496e #6 [ffff891ee0003a90] bad_area_nosemaphore at ffffffffbd074a64 #7 [ffff891ee0003aa0] __do_page_fault at ffffffffbd074b0a #8 [ffff891ee0003b18] do_page_fault at ffffffffbd074fc8 #9 [ffff891ee0003b50] page_fault at ffffffffbda01925 [exception RIP: qlt_schedule_sess_for_deletion+15] RIP: ffffffffc02e526f RSP: ffff891ee0003c08 RFLAGS: 00010046 RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffffc0307847 RDX: 00000000000020e6 RSI: ffff891edbc377c8 RDI: 0000000000000000 RBP: ffff891ee0003c18 R8: ffffffffc02f0b20 R9: 0000000000000250 R10: 0000000000000258 R11: 000000000000b780 R12: ffff891ed9b43000 R13: 00000000000000f0 R14: 0000000000000006 R15: ffff891edbc377c8 ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0018 #10 [ffff891ee0003c20] qla2x00_fcport_event_handler at ffffffffc02853d3 [qla2xxx] #11 [ffff891ee0003cf0] __dta_qla24xx_async_gnl_sp_done_333 at ffffffffc0285a1d [qla2xxx] #12 [ffff891ee0003de8] qla24xx_process_response_queue at ffffffffc02a2eb5 [qla2xxx] #13 [ffff891ee0003e88] qla24xx_msix_rsp_q at ffffffffc02a5403 [qla2xxx] #14 [ffff891ee0003ec0] __handle_irq_event_percpu at ffffffffbd0f4c59 #15 [ffff891ee0003f10] handle_irq_event_percpu at ffffffffbd0f4e02 #16 [ffff891ee0003f40] handle_irq_event at ffffffffbd0f4e90 #17 [ffff891ee0003f68] handle_edge_irq at ffffffffbd0f8984 #18 [ffff891ee0003f88] handle_irq at ffffffffbd0305d5 #19 [ffff891ee0003fb8] do_IRQ at ffffffffbda02a18 --- <IRQ stack> --- #20 [ffffffffbe403d30] ret_from_intr at ffffffffbda0094e [exception RIP: unknown or invalid address] RIP: 000000000000001f RSP: 0000000000000000 RFLAGS: fff3b8c2091ebb3f RAX: ffffbba5a0000200 RBX: 0000be8cdfa8f9fa RCX: 0000000000000018 RDX: 0000000000000101 RSI: 000000000000015d RDI: 0000000000000193 RBP: 0000000000000083 R8: ffffffffbe403e38 R9: 0000000000000002 R10: 0000000000000000 R11: ffffffffbe56b820 R12: ffff891ee001cf00 R13: ffffffffbd11c0a4 R14: ffffffffbe403d60 R15: 0000000000000001 ORIG_RAX: ffff891ee0022ac0 CS: 0000 SS: ffffffffffffffb9 bt: WARNING: possibly bogus exception frame #21 [ffffffffbe403dd8] cpuidle_enter_state at ffffffffbd67c6fd #22 [ffffffffbe403e40] cpuidle_enter at ffffffffbd67c907 #23 [ffffffffbe403e50] call_cpuidle at ffffffffbd0d98f3 #24 [ffffffffbe403e60] do_idle at ffffffffbd0d9b42 #25 [ffffffffbe403e98] cpu_startup_entry at ffffffffbd0d9da3 #26 [ffffffffbe403ec0] rest_init at ffffffffbd81d4aa #27 [ffffffffbe403ed0] start_kernel at ffffffffbe67d2ca #28 [ffffffffbe403f28] x86_64_start_reservations at ffffffffbe67c675 #29 [ffffffffbe403f38] x86_64_start_kernel at ffffffffbe67c6eb #30 [ffffffffbe403f50] secondary_startup_64 at ffffffffbd0000d5 Fixes: 040036b ("scsi: qla2xxx: Delay loop id allocation at login") Cc: <stable@vger.kernel.org> # v4.17+ Signed-off-by: Chuck Anderson <chuck.anderson@oracle.com> Signed-off-by: Himanshu Madhani <himanshu.madhani@cavium.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

Syzbot reported a read beyond the end of the skb head when returning IPV6_ORIGDSTADDR: BUG: KMSAN: kernel-infoleak in put_cmsg+0x5ef/0x860 net/core/scm.c:242 CPU: 0 PID: 4501 Comm: syz-executor128 Not tainted 4.17.0+ #9 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x185/0x1d0 lib/dump_stack.c:113 kmsan_report+0x188/0x2a0 mm/kmsan/kmsan.c:1125 kmsan_internal_check_memory+0x138/0x1f0 mm/kmsan/kmsan.c:1219 kmsan_copy_to_user+0x7a/0x160 mm/kmsan/kmsan.c:1261 copy_to_user include/linux/uaccess.h:184 [inline] put_cmsg+0x5ef/0x860 net/core/scm.c:242 ip6_datagram_recv_specific_ctl+0x1cf3/0x1eb0 net/ipv6/datagram.c:719 ip6_datagram_recv_ctl+0x41c/0x450 net/ipv6/datagram.c:733 rawv6_recvmsg+0x10fb/0x1460 net/ipv6/raw.c:521 [..] This logic and its ipv4 counterpart read the destination port from the packet at skb_transport_offset(skb) + 4. With MSG_MORE and a local SOCK_RAW sender, syzbot was able to cook a packet that stores headers exactly up to skb_transport_offset(skb) in the head and the remainder in a frag. Call pskb_may_pull before accessing the pointer to ensure that it lies in skb head. Link: http://lkml.kernel.org/r/CAF=yD-LEJwZj5a1-bAAj2Oy_hKmGygV6rsJ_WOrAYnv-fnayiQ@mail.gmail.com Reported-by: syzbot+9adb4b567003cac781f0@syzkaller.appspotmail.com Signed-off-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>

cachefiles_read_waiter() has the right to access a 'monitor' object by virtue of being called under the waitqueue lock for one of the pages in its purview. However, it has no ref on that monitor object or on the associated operation. What it is allowed to do is to move the monitor object to the operation's to_do list, but once it drops the work_lock, it's actually no longer permitted to access that object. However, it is trying to enqueue the retrieval operation for processing - but it can only do this via a pointer in the monitor object, something it shouldn't be doing. If it doesn't enqueue the operation, the operation may not get processed. If the order is flipped so that the enqueue is first, then it's possible for the work processor to look at the to_do list before the monitor is enqueued upon it. Fix this by getting a ref on the operation so that we can trust that it will still be there once we've added the monitor to the to_do list and dropped the work_lock. The op can then be enqueued after the lock is dropped. The bug can manifest in one of a couple of ways. The first manifestation looks like: FS-Cache: FS-Cache: Assertion failed FS-Cache: 6 == 5 is false ------------[ cut here ]------------ kernel BUG at fs/fscache/operation.c:494! RIP: 0010:fscache_put_operation+0x1e3/0x1f0 ... fscache_op_work_func+0x26/0x50 process_one_work+0x131/0x290 worker_thread+0x45/0x360 kthread+0xf8/0x130 ? create_worker+0x190/0x190 ? kthread_cancel_work_sync+0x10/0x10 ret_from_fork+0x1f/0x30 This is due to the operation being in the DEAD state (6) rather than INITIALISED, COMPLETE or CANCELLED (5) because it's already passed through fscache_put_operation(). The bug can also manifest like the following: kernel BUG at fs/fscache/operation.c:69! ... [exception RIP: fscache_enqueue_operation+246] ... #7 [ffff883fff083c10] fscache_enqueue_operation at ffffffffa0b793c6 #8 [ffff883fff083c28] cachefiles_read_waiter at ffffffffa0b15a48 #9 [ffff883fff083c48] __wake_up_common at ffffffff810af028 I'm not entirely certain as to which is line 69 in Lei's kernel, so I'm not entirely clear which assertion failed. Fixes: 9ae326a ("CacheFiles: A cache that backs onto a mounted filesystem") Reported-by: Lei Xue <carmark.dlut@gmail.com> Reported-by: Vegard Nossum <vegard.nossum@gmail.com> Reported-by: Anthony DeRobertis <aderobertis@metrics.net> Reported-by: NeilBrown <neilb@suse.com> Reported-by: Daniel Axtens <dja@axtens.net> Reported-by: Kiran Kumar Modukuri <kiran.modukuri@gmail.com> Signed-off-by: David Howells <dhowells@redhat.com> Reviewed-by: Daniel Axtens <dja@axtens.net>

@p-

…ilure While forking, if delayacct init fails due to memory shortage, it continues expecting all delayacct users to check task->delays pointer against NULL before dereferencing it, which all of them used to do. Commit c96f547 ("delayacct: Account blkio completion on the correct task"), while updating delayacct_blkio_end() to take the target task instead of always using %current, made the function test NULL on %current->delays and then continue to operated on @p->delays. If %current succeeded init while @p didn't, it leads to the following crash. BUG: unable to handle kernel NULL pointer dereference at 0000000000000004 IP: __delayacct_blkio_end+0xc/0x40 PGD 8000001fd07e1067 P4D 8000001fd07e1067 PUD 1fcffbb067 PMD 0 Oops: 0000 [#1] SMP PTI CPU: 4 PID: 25774 Comm: QIOThread0 Not tainted 4.16.0-9_fbk1_rc2_1180_g6b593215b4d7 #9 RIP: 0010:__delayacct_blkio_end+0xc/0x40 Call Trace: try_to_wake_up+0x2c0/0x600 autoremove_wake_function+0xe/0x30 __wake_up_common+0x74/0x120 wake_up_page_bit+0x9c/0xe0 mpage_end_io+0x27/0x70 blk_update_request+0x78/0x2c0 scsi_end_request+0x2c/0x1e0 scsi_io_completion+0x20b/0x5f0 blk_mq_complete_request+0xa2/0x100 ata_scsi_qc_complete+0x79/0x400 ata_qc_complete_multiple+0x86/0xd0 ahci_handle_port_interrupt+0xc9/0x5c0 ahci_handle_port_intr+0x54/0xb0 ahci_single_level_irq_intr+0x3b/0x60 __handle_irq_event_percpu+0x43/0x190 handle_irq_event_percpu+0x20/0x50 handle_irq_event+0x2a/0x50 handle_edge_irq+0x80/0x1c0 handle_irq+0xaf/0x120 do_IRQ+0x41/0xc0 common_interrupt+0xf/0xf Fix it by updating delayacct_blkio_end() check @p->delays instead. Link: http://lkml.kernel.org/r/20180724175542.GP1934745@devbig577.frc2.facebook.com Fixes: c96f547 ("delayacct: Account blkio completion on the correct task") Signed-off-by: Tejun Heo <tj@kernel.org> Reported-by: Dave Jones <dsj@fb.com> Debugged-by: Dave Jones <dsj@fb.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Josh Snyder <joshs@netflix.com> Cc: <stable@vger.kernel.org> [4.15+] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Kernel panic when with high memory pressure, calltrace looks like, PID: 21439 TASK: ffff881be3afedd0 CPU: 16 COMMAND: "java" #0 [ffff881ec7ed7630] machine_kexec at ffffffff81059beb #1 [ffff881ec7ed7690] __crash_kexec at ffffffff81105942 #2 [ffff881ec7ed7760] crash_kexec at ffffffff81105a30 #3 [ffff881ec7ed7778] oops_end at ffffffff816902c8 #4 [ffff881ec7ed77a0] no_context at ffffffff8167ff46 #5 [ffff881ec7ed77f0] __bad_area_nosemaphore at ffffffff8167ffdc #6 [ffff881ec7ed7838] __node_set at ffffffff81680300 #7 [ffff881ec7ed7860] __do_page_fault at ffffffff8169320f #8 [ffff881ec7ed78c0] do_page_fault at ffffffff816932b5 #9 [ffff881ec7ed78f0] page_fault at ffffffff8168f4c8 [exception RIP: _raw_spin_lock_irqsave+47] RIP: ffffffff8168edef RSP: ffff881ec7ed79a8 RFLAGS: 00010046 RAX: 0000000000000246 RBX: ffffea0019740d00 RCX: ffff881ec7ed7fd8 RDX: 0000000000020000 RSI: 0000000000000016 RDI: 0000000000000008 RBP: ffff881ec7ed79a8 R8: 0000000000000246 R9: 000000000001a098 R10: ffff88107ffda000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000008 R14: ffff881ec7ed7a80 R15: ffff881be3afedd0 ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0018 It happens in the pagefault and results in double pagefault during compacting pages when memory allocation fails. Analysed the vmcore, the page leads to second pagefault is corrupted with _mapcount=-256, but private=0. It's caused by the race between migration and ballooning, and lock missing in virtballoon_migratepage() of virtio_balloon driver. This patch fix the bug. Fixes: e225042 ("virtio_balloon: introduce migration primitives to balloon pages") Cc: stable@vger.kernel.org Signed-off-by: Jiang Biao <jiang.biao2@zte.com.cn> Signed-off-by: Huang Chong <huang.chong@zte.com.cn> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

Deferred struct page init is needed only on systems with large amount of physical memory to improve boot performance. 32-bit systems do not benefit from this feature. Jiri reported a problem where deferred struct pages do not work well with x86-32: [ 0.035162] Dentry cache hash table entries: 131072 (order: 7, 524288 bytes) [ 0.035725] Inode-cache hash table entries: 65536 (order: 6, 262144 bytes) [ 0.036269] Initializing CPU#0 [ 0.036513] Initializing HighMem for node 0 (00036ffe:0007ffe0) [ 0.038459] page:f6780000 is uninitialized and poisoned [ 0.038460] raw: ffffffff ffffffff ffffffff ffffffff ffffffff ffffffff ffffffff ffffffff [ 0.039509] page dumped because: VM_BUG_ON_PAGE(1 && PageCompound(page)) [ 0.040038] ------------[ cut here ]------------ [ 0.040399] kernel BUG at include/linux/page-flags.h:293! [ 0.040823] invalid opcode: 0000 [#1] SMP PTI [ 0.041166] CPU: 0 PID: 0 Comm: swapper Not tainted 4.19.0-rc1_pt_jiri #9 [ 0.041694] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.11.0-20171110_100015-anatol 04/01/2014 [ 0.042496] EIP: free_highmem_page+0x64/0x80 [ 0.042839] Code: 13 46 d8 c1 e8 18 5d 83 e0 03 8d 04 c0 c1 e0 06 ff 80 ec 5f 44 d8 c3 8d b4 26 00 00 00 00 ba 08 65 28 d8 89 d8 e8 fc 71 02 00 <0f> 0b 8d 76 00 8d bc 27 00 00 00 00 ba d0 b1 26 d8 89 d8 e8 e4 71 [ 0.044338] EAX: 0000003c EBX: f6780000 ECX: 00000000 EDX: d856cbe8 [ 0.044868] ESI: 0007ffe0 EDI: d838df20 EBP: d838df00 ESP: d838defc [ 0.045372] DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068 EFLAGS: 00210086 [ 0.045913] CR0: 80050033 CR2: 00000000 CR3: 18556000 CR4: 00040690 [ 0.046413] DR0: 00000000 DR1: 00000000 DR2: 00000000 DR3: 00000000 [ 0.046913] DR6: fffe0ff0 DR7: 00000400 [ 0.047220] Call Trace: [ 0.047419] add_highpages_with_active_regions+0xbd/0x10d [ 0.047854] set_highmem_pages_init+0x5b/0x71 [ 0.048202] mem_init+0x2b/0x1e8 [ 0.048460] start_kernel+0x1d2/0x425 [ 0.048757] i386_start_kernel+0x93/0x97 [ 0.049073] startup_32_smp+0x164/0x168 [ 0.049379] Modules linked in: [ 0.049626] ---[ end trace 337949378db0abbb ]--- We free highmem pages before their struct pages are initialized: mem_init() set_highmem_pages_init() add_highpages_with_active_regions() free_highmem_page() .. Access uninitialized struct page here.. Because there is no reason to have this feature on 32-bit systems, just disable it. Link: http://lkml.kernel.org/r/20180831150506.31246-1-pavel.tatashin@microsoft.com Fixes: 2e3ca40 ("mm: relax deferred struct page requirements") Signed-off-by: Pavel Tatashin <pavel.tatashin@microsoft.com> Reported-by: Jiri Slaby <jslaby@suse.cz> Acked-by: Michal Hocko <mhocko@suse.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Defer probe of qman portals after qman probing. This fixes the crash below, seen on NXP LS1043A SoCs: Unable to handle kernel NULL pointer dereference at virtual address 0000000000000004 Mem abort info: ESR = 0x96000004 Exception class = DABT (current EL), IL = 32 bits SET = 0, FnV = 0 EA = 0, S1PTW = 0 Data abort info: ISV = 0, ISS = 0x00000004 CM = 0, WnR = 0 [0000000000000004] user address but active_mm is swapper Internal error: Oops: 96000004 [#1] PREEMPT SMP Modules linked in: CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.18.0-rc1-next-20180622-00200-g986f5c179185 #9 Hardware name: LS1043A RDB Board (DT) pstate: 80000005 (Nzcv daif -PAN -UAO) pc : qman_set_sdest+0x74/0xa0 lr : qman_portal_probe+0x22c/0x470 sp : ffff00000803bbc0 x29: ffff00000803bbc0 x28: 0000000000000000 x27: ffff0000090c1b88 x26: ffff00000927cb68 x25: ffff00000927c000 x24: ffff00000927cb60 x23: 0000000000000000 x22: 0000000000000000 x21: ffff0000090e9000 x20: ffff800073b5c810 x19: ffff800027401298 x18: ffffffffffffffff x17: 0000000000000001 x16: 0000000000000000 x15: ffff0000090e96c8 x14: ffff80002740138a x13: ffff0000090f2000 x12: 0000000000000030 x11: ffff000008f25000 x10: 0000000000000000 x9 : ffff80007bdfd2c0 x8 : 0000000000004000 x7 : ffff80007393cc18 x6 : 0040000000000001 x5 : 0000000000000000 x4 : ffffffffffffffff x3 : 0000000000000004 x2 : ffff00000927c900 x1 : 0000000000000000 x0 : 0000000000000004 Process swapper/0 (pid: 1, stack limit = 0x(____ptrval____)) Call trace: qman_set_sdest+0x74/0xa0 platform_drv_probe+0x50/0xa8 driver_probe_device+0x214/0x2f8 __driver_attach+0xd8/0xe0 bus_for_each_dev+0x68/0xc8 driver_attach+0x20/0x28 bus_add_driver+0x108/0x228 driver_register+0x60/0x110 __platform_driver_register+0x40/0x48 qman_portal_driver_init+0x20/0x84 do_one_initcall+0x58/0x168 kernel_init_freeable+0x184/0x22c kernel_init+0x10/0x108 ret_from_fork+0x10/0x18 Code: f9400443 11001000 927e4800 8b000063 (b9400063) ---[ end trace 4f6d50489ecfb930 ]--- Kernel panic - not syncing: Attempted to kill init! exitcode=0x0000000b Signed-off-by: Laurentiu Tudor <laurentiu.tudor@nxp.com> Signed-off-by: Li Yang <leoyang.li@nxp.com>

Increase kasan instrumented kernel stack size from 32k to 64k. Other architectures seems to get away with just doubling kernel stack size under kasan, but on s390 this appears to be not enough due to bigger frame size. The particular pain point is kasan inlined checks (CONFIG_KASAN_INLINE vs CONFIG_KASAN_OUTLINE). With inlined checks one particular case hitting stack overflow is fs sync on xfs filesystem: #0 [9a0681e8] 704 bytes check_usage at 34b1fc #1 [9a0684a8] 432 bytes check_usage at 34c710 #2 [9a068658] 1048 bytes validate_chain at 35044a #3 [9a068a70] 312 bytes __lock_acquire at 3559fe #4 [9a068ba8] 440 bytes lock_acquire at 3576ee #5 [9a068d60] 104 bytes _raw_spin_lock at 21b44e0 #6 [9a068dc8] 1992 bytes enqueue_entity at 2dbf72 #7 [9a069590] 1496 bytes enqueue_task_fair at 2df5f0 #8 [9a069b68] 64 bytes ttwu_do_activate at 28f438 #9 [9a069ba8] 552 bytes try_to_wake_up at 298c4c #10 [9a069dd0] 168 bytes wake_up_worker at 23f97c #11 [9a069e78] 200 bytes insert_work at 23fc2e #12 [9a069f40] 648 bytes __queue_work at 2487c0 #13 [9a06a1c8] 200 bytes __queue_delayed_work at 24db28 #14 [9a06a290] 248 bytes mod_delayed_work_on at 24de84 #15 [9a06a388] 24 bytes kblockd_mod_delayed_work_on at 153e2a0 #16 [9a06a3a0] 288 bytes __blk_mq_delay_run_hw_queue at 158168c #17 [9a06a4c0] 192 bytes blk_mq_run_hw_queue at 1581a3c #18 [9a06a580] 184 bytes blk_mq_sched_insert_requests at 15a2192 #19 [9a06a638] 1024 bytes blk_mq_flush_plug_list at 1590f3a #20 [9a06aa38] 704 bytes blk_flush_plug_list at 1555028 #21 [9a06acf8] 320 bytes schedule at 219e476 #22 [9a06ae38] 760 bytes schedule_timeout at 21b0aac #23 [9a06b130] 408 bytes wait_for_common at 21a1706 #24 [9a06b2c8] 360 bytes xfs_buf_iowait at fa1540 #25 [9a06b430] 256 bytes __xfs_buf_submit at fadae6 #26 [9a06b530] 264 bytes xfs_buf_read_map at fae3f6 #27 [9a06b638] 656 bytes xfs_trans_read_buf_map at 10ac9a8 #28 [9a06b8c8] 304 bytes xfs_btree_kill_root at e72426 #29 [9a06b9f8] 288 bytes xfs_btree_lookup_get_block at e7bc5e #30 [9a06bb18] 624 bytes xfs_btree_lookup at e7e1a6 #31 [9a06bd88] 2664 bytes xfs_alloc_ag_vextent_near at dfa070 #32 [9a06c7f0] 144 bytes xfs_alloc_ag_vextent at dff3ca #33 [9a06c880] 1128 bytes xfs_alloc_vextent at e05fce #34 [9a06cce8] 584 bytes xfs_bmap_btalloc at e58342 #35 [9a06cf30] 1336 bytes xfs_bmapi_write at e618de #36 [9a06d468] 776 bytes xfs_iomap_write_allocate at ff678e #37 [9a06d770] 720 bytes xfs_map_blocks at f82af8 #38 [9a06da40] 928 bytes xfs_writepage_map at f83cd6 #39 [9a06dde0] 320 bytes xfs_do_writepage at f85872 #40 [9a06df20] 1320 bytes write_cache_pages at 73dfe8 #41 [9a06e448] 208 bytes xfs_vm_writepages at f7f892 #42 [9a06e518] 88 bytes do_writepages at 73fe6a #43 [9a06e570] 872 bytes __writeback_single_inode at a20cb6 #44 [9a06e8d8] 664 bytes writeback_sb_inodes at a23be2 #45 [9a06eb70] 296 bytes __writeback_inodes_wb at a242e0 #46 [9a06ec98] 928 bytes wb_writeback at a2500e #47 [9a06f038] 848 bytes wb_do_writeback at a260ae #48 [9a06f388] 536 bytes wb_workfn at a28228 #49 [9a06f5a0] 1088 bytes process_one_work at 24a234 #50 [9a06f9e0] 1120 bytes worker_thread at 24ba26 #51 [9a06fe40] 104 bytes kthread at 26545a #52 [9a06fea8] kernel_thread_starter at 21b6b62 To be able to increase the stack size to 64k reuse LLILL instruction in __switch_to function to load 64k - STACK_FRAME_OVERHEAD - __PT_SIZE (65192) value as unsigned. Reported-by: Benjamin Block <bblock@linux.ibm.com> Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

info->nr_rings isn't adjusted in case of ENOMEM error from negotiate_mq(). This leads to kernel panic in error path. Typical call stack involving panic - #8 page_fault at ffffffff8175936f [exception RIP: blkif_free_ring+33] RIP: ffffffffa0149491 RSP: ffff8804f7673c08 RFLAGS: 00010292 ... #9 blkif_free at ffffffffa0149aaa [xen_blkfront] #10 talk_to_blkback at ffffffffa014c8cd [xen_blkfront] #11 blkback_changed at ffffffffa014ea8b [xen_blkfront] #12 xenbus_otherend_changed at ffffffff81424670 #13 backend_changed at ffffffff81426dc3 #14 xenwatch_thread at ffffffff81422f29 #15 kthread at ffffffff810abe6a #16 ret_from_fork at ffffffff81754078 Cc: stable@vger.kernel.org Fixes: 7ed8ce1 ("xen-blkfront: move negotiate_mq to cover all cases of new VBDs") Signed-off-by: Manjunath Patil <manjunath.b.patil@oracle.com> Acked-by: Roger Pau Monné <roger.pau@citrix.com> Signed-off-by: Juergen Gross <jgross@suse.com>

Seeing as we use this registermap in the context of our IRQ handlers, we need to be using spinlocks for reading/writing registers so that we can still read them from IRQ handlers without having to grab any mutexes and accidentally sleep. We don't currently do this, as pointed out by lockdep: [ 18.403770] BUG: sleeping function called from invalid context at kernel/locking/mutex.c:908 [ 18.406744] in_atomic(): 1, irqs_disabled(): 128, pid: 68, name: kworker/u17:0 [ 18.413864] INFO: lockdep is turned off. [ 18.417675] irq event stamp: 12 [ 18.420778] hardirqs last enabled at (11): [<ffff000008a4f57c>] _raw_spin_unlock_irq+0x2c/0x60 [ 18.429510] hardirqs last disabled at (12): [<ffff000008a48914>] __schedule+0xc4/0xa60 [ 18.437345] softirqs last enabled at (0): [<ffff0000080b55e0>] copy_process.isra.4.part.5+0x4d8/0x1c50 [ 18.446684] softirqs last disabled at (0): [<0000000000000000>] (null) [ 18.453979] CPU: 0 PID: 68 Comm: kworker/u17:0 Tainted: G W O 4.20.0-rc3Lyude-Test+ #9 [ 18.469839] Hardware name: amlogic khadas-vim2/khadas-vim2, BIOS 2018.07-rc2-armbian 09/11/2018 [ 18.480037] Workqueue: hci0 hci_power_on [bluetooth] [ 18.487138] Call trace: [ 18.494192] dump_backtrace+0x0/0x1b8 [ 18.501280] show_stack+0x14/0x20 [ 18.508361] dump_stack+0xbc/0xf4 [ 18.515427] ___might_sleep+0x140/0x1d8 [ 18.522515] __might_sleep+0x50/0x88 [ 18.529582] __mutex_lock+0x60/0x870 [ 18.536621] mutex_lock_nested+0x1c/0x28 [ 18.543660] regmap_lock_mutex+0x10/0x18 [ 18.550696] regmap_read+0x38/0x70 [ 18.557727] dw_hdmi_hardirq+0x58/0x138 [dw_hdmi] [ 18.564804] __handle_irq_event_percpu+0xac/0x410 [ 18.571891] handle_irq_event_percpu+0x34/0x88 [ 18.578982] handle_irq_event+0x48/0x78 [ 18.586051] handle_fasteoi_irq+0xac/0x160 [ 18.593061] generic_handle_irq+0x24/0x38 [ 18.599989] __handle_domain_irq+0x60/0xb8 [ 18.606857] gic_handle_irq+0x50/0xa0 [ 18.613659] el1_irq+0xb4/0x130 [ 18.620394] debug_lockdep_rcu_enabled+0x2c/0x30 [ 18.627111] schedule+0x38/0xa0 [ 18.633781] schedule_timeout+0x3a8/0x510 [ 18.640389] wait_for_common+0x15c/0x180 [ 18.646905] wait_for_completion+0x14/0x20 [ 18.653319] mmc_wait_for_req_done+0x28/0x168 [ 18.659693] mmc_wait_for_req+0xa8/0xe8 [ 18.665978] mmc_wait_for_cmd+0x64/0x98 [ 18.672180] mmc_io_rw_direct_host+0x94/0x130 [ 18.678385] mmc_io_rw_direct+0x10/0x18 [ 18.684516] sdio_enable_func+0xe8/0x1d0 [ 18.690627] btsdio_open+0x24/0xc0 [btsdio] [ 18.696821] hci_dev_do_open+0x64/0x598 [bluetooth] [ 18.703025] hci_power_on+0x50/0x270 [bluetooth] [ 18.709163] process_one_work+0x2a0/0x6e0 [ 18.715252] worker_thread+0x40/0x448 [ 18.721310] kthread+0x12c/0x130 [ 18.727326] ret_from_fork+0x10/0x1c [ 18.735555] ------------[ cut here ]------------ [ 18.741430] do not call blocking ops when !TASK_RUNNING; state=2 set at [<000000006265ec59>] wait_for_common+0x140/0x180 [ 18.752417] WARNING: CPU: 0 PID: 68 at kernel/sched/core.c:6096 __might_sleep+0x7c/0x88 [ 18.760553] Modules linked in: dm_mirror dm_region_hash dm_log dm_mod btsdio bluetooth snd_soc_hdmi_codec dw_hdmi_i2s_audio ecdh_generic brcmfmac brcmutil cfg80211 rfkill ir_nec_decoder meson_dw_hdmi(O) dw_hdmi rc_geekbox meson_rng meson_ir ao_cec rng_core rc_core cec leds_pwm efivars nfsd ip_tables x_tables crc32_generic f2fs uas meson_gxbb_wdt pwm_meson efivarfs ipv6 [ 18.799469] CPU: 0 PID: 68 Comm: kworker/u17:0 Tainted: G W O 4.20.0-rc3Lyude-Test+ #9 [ 18.808858] Hardware name: amlogic khadas-vim2/khadas-vim2, BIOS 2018.07-rc2-armbian 09/11/2018 [ 18.818045] Workqueue: hci0 hci_power_on [bluetooth] [ 18.824088] pstate: 80000085 (Nzcv daIf -PAN -UAO) [ 18.829891] pc : __might_sleep+0x7c/0x88 [ 18.835722] lr : __might_sleep+0x7c/0x88 [ 18.841256] sp : ffff000008003cb0 [ 18.846751] x29: ffff000008003cb0 x28: 0000000000000000 [ 18.852269] x27: ffff00000938e000 x26: ffff800010283000 [ 18.857726] x25: ffff800010353280 x24: ffff00000868ef50 [ 18.863166] x23: 0000000000000000 x22: 0000000000000000 [ 18.868551] x21: 0000000000000000 x20: 000000000000038c [ 18.873850] x19: ffff000008cd08c0 x18: 0000000000000010 [ 18.879081] x17: ffff000008a68cb0 x16: 0000000000000000 [ 18.884197] x15: 0000000000aaaaaa x14: 0e200e200e200e20 [ 18.889239] x13: 0000000000000001 x12: 00000000ffffffff [ 18.894261] x11: ffff000008adfa48 x10: 0000000000000001 [ 18.899517] x9 : ffff0000092a0158 x8 : 0000000000000000 [ 18.904674] x7 : ffff00000812136c x6 : 0000000000000000 [ 18.909895] x5 : 0000000000000000 x4 : 0000000000000001 [ 18.915080] x3 : 0000000000000007 x2 : 0000000000000007 [ 18.920269] x1 : 99ab8e9ebb6c8500 x0 : 0000000000000000 [ 18.925443] Call trace: [ 18.929904] __might_sleep+0x7c/0x88 [ 18.934311] __mutex_lock+0x60/0x870 [ 18.938687] mutex_lock_nested+0x1c/0x28 [ 18.943076] regmap_lock_mutex+0x10/0x18 [ 18.947453] regmap_read+0x38/0x70 [ 18.951842] dw_hdmi_hardirq+0x58/0x138 [dw_hdmi] [ 18.956269] __handle_irq_event_percpu+0xac/0x410 [ 18.960712] handle_irq_event_percpu+0x34/0x88 [ 18.965176] handle_irq_event+0x48/0x78 [ 18.969612] handle_fasteoi_irq+0xac/0x160 [ 18.974058] generic_handle_irq+0x24/0x38 [ 18.978501] __handle_domain_irq+0x60/0xb8 [ 18.982938] gic_handle_irq+0x50/0xa0 [ 18.987351] el1_irq+0xb4/0x130 [ 18.991734] debug_lockdep_rcu_enabled+0x2c/0x30 [ 18.996180] schedule+0x38/0xa0 [ 19.000609] schedule_timeout+0x3a8/0x510 [ 19.005064] wait_for_common+0x15c/0x180 [ 19.009513] wait_for_completion+0x14/0x20 [ 19.013951] mmc_wait_for_req_done+0x28/0x168 [ 19.018402] mmc_wait_for_req+0xa8/0xe8 [ 19.022809] mmc_wait_for_cmd+0x64/0x98 [ 19.027177] mmc_io_rw_direct_host+0x94/0x130 [ 19.031563] mmc_io_rw_direct+0x10/0x18 [ 19.035922] sdio_enable_func+0xe8/0x1d0 [ 19.040294] btsdio_open+0x24/0xc0 [btsdio] [ 19.044742] hci_dev_do_open+0x64/0x598 [bluetooth] [ 19.049228] hci_power_on+0x50/0x270 [bluetooth] [ 19.053687] process_one_work+0x2a0/0x6e0 [ 19.058143] worker_thread+0x40/0x448 [ 19.062608] kthread+0x12c/0x130 [ 19.067064] ret_from_fork+0x10/0x1c [ 19.071513] irq event stamp: 12 [ 19.075937] hardirqs last enabled at (11): [<ffff000008a4f57c>] _raw_spin_unlock_irq+0x2c/0x60 [ 19.083560] hardirqs last disabled at (12): [<ffff000008a48914>] __schedule+0xc4/0xa60 [ 19.091401] softirqs last enabled at (0): [<ffff0000080b55e0>] copy_process.isra.4.part.5+0x4d8/0x1c50 [ 19.100801] softirqs last disabled at (0): [<0000000000000000>] (null) [ 19.108135] ---[ end trace 38c4920787b88c75 ]--- So, fix this by enabling the fast_io option in our regmap config so that regmap uses spinlocks for locking instead of mutexes. Signed-off-by: Lyude Paul <lyude@redhat.com> Fixes: 3f68be7 ("drm/meson: Add support for HDMI encoder and DW-HDMI bridge + PHY") Cc: Daniel Vetter <daniel.vetter@ffwll.ch> Cc: Neil Armstrong <narmstrong@baylibre.com> Cc: Carlo Caione <carlo@caione.org> Cc: Kevin Hilman <khilman@baylibre.com> Cc: dri-devel@lists.freedesktop.org Cc: linux-amlogic@lists.infradead.org Cc: linux-arm-kernel@lists.infradead.org Cc: <stable@vger.kernel.org> # v4.12+ Acked-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Neil Armstrong <narmstrong@baylibre.com> Link: https://patchwork.freedesktop.org/patch/msgid/20181124191238.28276-1-lyude@redhat.com Signed-off-by: Sean Paul <seanpaul@chromium.org>

It was observed that a process blocked indefintely in __fscache_read_or_alloc_page(), waiting for FSCACHE_COOKIE_LOOKING_UP to be cleared via fscache_wait_for_deferred_lookup(). At this time, ->backing_objects was empty, which would normaly prevent __fscache_read_or_alloc_page() from getting to the point of waiting. This implies that ->backing_objects was cleared *after* __fscache_read_or_alloc_page was was entered. When an object is "killed" and then "dropped", FSCACHE_COOKIE_LOOKING_UP is cleared in fscache_lookup_failure(), then KILL_OBJECT and DROP_OBJECT are "called" and only in DROP_OBJECT is ->backing_objects cleared. This leaves a window where something else can set FSCACHE_COOKIE_LOOKING_UP and __fscache_read_or_alloc_page() can start waiting, before ->backing_objects is cleared There is some uncertainty in this analysis, but it seems to be fit the observations. Adding the wake in this patch will be handled correctly by __fscache_read_or_alloc_page(), as it checks if ->backing_objects is empty again, after waiting. Customer which reported the hang, also report that the hang cannot be reproduced with this fix. The backtrace for the blocked process looked like: PID: 29360 TASK: ffff881ff2ac0f80 CPU: 3 COMMAND: "zsh" #0 [ffff881ff43efbf8] schedule at ffffffff815e56f1 #1 [ffff881ff43efc58] bit_wait at ffffffff815e64ed #2 [ffff881ff43efc68] __wait_on_bit at ffffffff815e61b8 #3 [ffff881ff43efca0] out_of_line_wait_on_bit at ffffffff815e625e #4 [ffff881ff43efd08] fscache_wait_for_deferred_lookup at ffffffffa04f2e8f [fscache] #5 [ffff881ff43efd18] __fscache_read_or_alloc_page at ffffffffa04f2ffe [fscache] #6 [ffff881ff43efd58] __nfs_readpage_from_fscache at ffffffffa0679668 [nfs] #7 [ffff881ff43efd78] nfs_readpage at ffffffffa067092b [nfs] #8 [ffff881ff43efda0] generic_file_read_iter at ffffffff81187a73 #9 [ffff881ff43efe50] nfs_file_read at ffffffffa066544b [nfs] #10 [ffff881ff43efe70] __vfs_read at ffffffff811fc756 #11 [ffff881ff43efee8] vfs_read at ffffffff811fccfa #12 [ffff881ff43eff18] sys_read at ffffffff811fda62 #13 [ffff881ff43eff50] entry_SYSCALL_64_fastpath at ffffffff815e986e Signed-off-by: NeilBrown <neilb@suse.com> Signed-off-by: David Howells <dhowells@redhat.com>

Function graph tracing recurses into itself when stackleak is enabled, causing the ftrace graph selftest to run for up to 90 seconds and trigger the softlockup watchdog. Breakpoint 2, ftrace_graph_caller () at ../arch/arm64/kernel/entry-ftrace.S:200 200 mcount_get_lr_addr x0 // pointer to function's saved lr (gdb) bt \#0 ftrace_graph_caller () at ../arch/arm64/kernel/entry-ftrace.S:200 \#1 0xffffff80081d5280 in ftrace_caller () at ../arch/arm64/kernel/entry-ftrace.S:153 \#2 0xffffff8008555484 in stackleak_track_stack () at ../kernel/stackleak.c:106 \#3 0xffffff8008421ff8 in ftrace_ops_test (ops=0xffffff8009eaa840 <graph_ops>, ip=18446743524091297036, regs=<optimized out>) at ../kernel/trace/ftrace.c:1507 \#4 0xffffff8008428770 in __ftrace_ops_list_func (regs=<optimized out>, ignored=<optimized out>, parent_ip=<optimized out>, ip=<optimized out>) at ../kernel/trace/ftrace.c:6286 \#5 ftrace_ops_no_ops (ip=18446743524091297036, parent_ip=18446743524091242824) at ../kernel/trace/ftrace.c:6321 \#6 0xffffff80081d5280 in ftrace_caller () at ../arch/arm64/kernel/entry-ftrace.S:153 \#7 0xffffff800832fd10 in irq_find_mapping (domain=0xffffffc03fc4bc80, hwirq=27) at ../kernel/irq/irqdomain.c:876 \#8 0xffffff800832294c in __handle_domain_irq (domain=0xffffffc03fc4bc80, hwirq=27, lookup=true, regs=0xffffff800814b840) at ../kernel/irq/irqdesc.c:650 \#9 0xffffff80081d52b4 in ftrace_graph_caller () at ../arch/arm64/kernel/entry-ftrace.S:205 Rework so we mark stackleak_track_stack as notrace Co-developed-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Anders Roxell <anders.roxell@linaro.org> Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Kees Cook <keescook@chromium.org>

The *_frag_reasm() functions are susceptible to miscalculating the byte count of packet fragments in case the truesize of a head buffer changes. The truesize member may be changed by the call to skb_unclone(), leaving the fragment memory limit counter unbalanced even if all fragments are processed. This miscalculation goes unnoticed as long as the network namespace which holds the counter is not destroyed. Should an attempt be made to destroy a network namespace that holds an unbalanced fragment memory limit counter the cleanup of the namespace never finishes. The thread handling the cleanup gets stuck in inet_frags_exit_net() waiting for the percpu counter to reach zero. The thread is usually in running state with a stacktrace similar to: PID: 1073 TASK: ffff880626711440 CPU: 1 COMMAND: "kworker/u48:4" #5 [ffff880621563d48] _raw_spin_lock at ffffffff815f5480 #6 [ffff880621563d48] inet_evict_bucket at ffffffff8158020b #7 [ffff880621563d80] inet_frags_exit_net at ffffffff8158051c #8 [ffff880621563db0] ops_exit_list at ffffffff814f5856 #9 [ffff880621563dd8] cleanup_net at ffffffff814f67c0 #10 [ffff880621563e38] process_one_work at ffffffff81096f14 It is not possible to create new network namespaces, and processes that call unshare() end up being stuck in uninterruptible sleep state waiting to acquire the net_mutex. The bug was observed in the IPv6 netfilter code by Per Sundstrom. I thank him for his analysis of the problem. The parts of this patch that apply to IPv4 and IPv6 fragment reassembly are preemptive measures. Signed-off-by: Jiri Wiesner <jwiesner@suse.com> Reported-by: Per Sundstrom <per.sundstrom@redqube.se> Acked-by: Peter Oskolkov <posk@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>

Commit 9b6f7e1 ("mm: rework memcg kernel stack accounting") will result in fork failing if allocating a kernel stack for a task in dup_task_struct exceeds the kernel memory allowance for that cgroup. Unfortunately, it also results in a crash. This is due to the code jumping to free_stack and calling free_thread_stack when the memcg kernel stack charge fails, but without tsk->stack pointing at the freshly allocated stack. This in turn results in the vfree_atomic in free_thread_stack oopsing with a backtrace like this: #5 [ffffc900244efc88] die at ffffffff8101f0ab #6 [ffffc900244efcb8] do_general_protection at ffffffff8101cb86 #7 [ffffc900244efce0] general_protection at ffffffff818ff082 [exception RIP: llist_add_batch+7] RIP: ffffffff8150d487 RSP: ffffc900244efd98 RFLAGS: 00010282 RAX: 0000000000000000 RBX: ffff88085ef55980 RCX: 0000000000000000 RDX: ffff88085ef55980 RSI: 343834343531203a RDI: 343834343531203a RBP: ffffc900244efd98 R8: 0000000000000001 R9: ffff8808578c3600 R10: 0000000000000000 R11: 0000000000000001 R12: ffff88029f6c21c0 R13: 0000000000000286 R14: ffff880147759b00 R15: 0000000000000000 ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0018 #8 [ffffc900244efda0] vfree_atomic at ffffffff811df2c7 #9 [ffffc900244efdb8] copy_process at ffffffff81086e37 #10 [ffffc900244efe98] _do_fork at ffffffff810884e0 #11 [ffffc900244eff10] sys_vfork at ffffffff810887ff #12 [ffffc900244eff20] do_syscall_64 at ffffffff81002a43 RIP: 000000000049b948 RSP: 00007ffcdb307830 RFLAGS: 00000246 RAX: ffffffffffffffda RBX: 0000000000896030 RCX: 000000000049b948 RDX: 0000000000000000 RSI: 00007ffcdb307790 RDI: 00000000005d7421 RBP: 000000000067370f R8: 00007ffcdb3077b0 R9: 000000000001ed00 R10: 0000000000000008 R11: 0000000000000246 R12: 0000000000000040 R13: 000000000000000f R14: 0000000000000000 R15: 000000000088d018 ORIG_RAX: 000000000000003a CS: 0033 SS: 002b The simplest fix is to assign tsk->stack right where it is allocated. Link: http://lkml.kernel.org/r/20181214231726.7ee4843c@imladris.surriel.com Fixes: 9b6f7e1 ("mm: rework memcg kernel stack accounting") Signed-off-by: Rik van Riel <riel@surriel.com> Acked-by: Roman Gushchin <guro@fb.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Shakeel Butt <shakeelb@google.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Tejun Heo <tj@kernel.org> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

When option CONFIG_KASAN is enabled toghether with ftrace, function ftrace_graph_caller() gets in to a recursion, via functions kasan_check_read() and kasan_check_write(). Breakpoint 2, ftrace_graph_caller () at ../arch/arm64/kernel/entry-ftrace.S:179 179 mcount_get_pc x0 // function's pc (gdb) bt #0 ftrace_graph_caller () at ../arch/arm64/kernel/entry-ftrace.S:179 #1 0xffffff90101406c8 in ftrace_caller () at ../arch/arm64/kernel/entry-ftrace.S:151 #2 0xffffff90106fd084 in kasan_check_write (p=0xffffffc06c170878, size=4) at ../mm/kasan/common.c:105 #3 0xffffff90104a2464 in atomic_add_return (v=<optimized out>, i=<optimized out>) at ./include/generated/atomic-instrumented.h:71 #4 atomic_inc_return (v=<optimized out>) at ./include/generated/atomic-fallback.h:284 #5 trace_graph_entry (trace=0xffffffc03f5ff380) at ../kernel/trace/trace_functions_graph.c:441 #6 0xffffff9010481774 in trace_graph_entry_watchdog (trace=<optimized out>) at ../kernel/trace/trace_selftest.c:741 #7 0xffffff90104a185c in function_graph_enter (ret=<optimized out>, func=<optimized out>, frame_pointer=18446743799894897728, retp=<optimized out>) at ../kernel/trace/trace_functions_graph.c:196 #8 0xffffff9010140628 in prepare_ftrace_return (self_addr=18446743592948977792, parent=0xffffffc03f5ff418, frame_pointer=18446743799894897728) at ../arch/arm64/kernel/ftrace.c:231 #9 0xffffff90101406f4 in ftrace_graph_caller () at ../arch/arm64/kernel/entry-ftrace.S:182 Backtrace stopped: previous frame identical to this frame (corrupt stack?) (gdb) Rework so that the kasan implementation isn't traced. Link: http://lkml.kernel.org/r/20181212183447.15890-1-anders.roxell@linaro.org Signed-off-by: Anders Roxell <anders.roxell@linaro.org> Acked-by: Dmitry Vyukov <dvyukov@google.com> Tested-by: Dmitry Vyukov <dvyukov@google.com> Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

The following leaks were detected by ASAN: Indirect leak of 360 byte(s) in 9 object(s) allocated from: #0 0x7fecc305180e in calloc (/lib/x86_64-linux-gnu/libasan.so.5+0x10780e) #1 0x560578f6dce5 in perf_pmu__new_format util/pmu.c:1333 #2 0x560578f752fc in perf_pmu_parse util/pmu.y:59 #3 0x560578f6a8b7 in perf_pmu__format_parse util/pmu.c:73 #4 0x560578e07045 in test__pmu tests/pmu.c:155 #5 0x560578de109b in run_test tests/builtin-test.c:410 #6 0x560578de109b in test_and_print tests/builtin-test.c:440 #7 0x560578de401a in __cmd_test tests/builtin-test.c:661 #8 0x560578de401a in cmd_test tests/builtin-test.c:807 #9 0x560578e49354 in run_builtin /home/namhyung/project/linux/tools/perf/perf.c:312 #10 0x560578ce71a8 in handle_internal_command /home/namhyung/project/linux/tools/perf/perf.c:364 #11 0x560578ce71a8 in run_argv /home/namhyung/project/linux/tools/perf/perf.c:408 #12 0x560578ce71a8 in main /home/namhyung/project/linux/tools/perf/perf.c:538 #13 0x7fecc2b7acc9 in __libc_start_main ../csu/libc-start.c:308 Fixes: cff7f95 ("perf tests: Move pmu tests into separate object") Signed-off-by: Namhyung Kim <namhyung@kernel.org> Acked-by: Jiri Olsa <jolsa@redhat.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Ian Rogers <irogers@google.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Link: http://lore.kernel.org/lkml/20200915031819.386559-12-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Very sporadically I had test case btrfs/069 from fstests hanging (for years, it is not a recent regression), with the following traces in dmesg/syslog: [162301.160628] BTRFS info (device sdc): dev_replace from /dev/sdd (devid 2) to /dev/sdg started [162301.181196] BTRFS info (device sdc): scrub: finished on devid 4 with status: 0 [162301.287162] BTRFS info (device sdc): dev_replace from /dev/sdd (devid 2) to /dev/sdg finished [162513.513792] INFO: task btrfs-transacti:1356167 blocked for more than 120 seconds. [162513.514318] Not tainted 5.9.0-rc6-btrfs-next-69 #1 [162513.514522] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [162513.514747] task:btrfs-transacti state:D stack: 0 pid:1356167 ppid: 2 flags:0x00004000 [162513.514751] Call Trace: [162513.514761] __schedule+0x5ce/0xd00 [162513.514765] ? _raw_spin_unlock_irqrestore+0x3c/0x60 [162513.514771] schedule+0x46/0xf0 [162513.514844] wait_current_trans+0xde/0x140 [btrfs] [162513.514850] ? finish_wait+0x90/0x90 [162513.514864] start_transaction+0x37c/0x5f0 [btrfs] [162513.514879] transaction_kthread+0xa4/0x170 [btrfs] [162513.514891] ? btrfs_cleanup_transaction+0x660/0x660 [btrfs] [162513.514894] kthread+0x153/0x170 [162513.514897] ? kthread_stop+0x2c0/0x2c0 [162513.514902] ret_from_fork+0x22/0x30 [162513.514916] INFO: task fsstress:1356184 blocked for more than 120 seconds. [162513.515192] Not tainted 5.9.0-rc6-btrfs-next-69 #1 [162513.515431] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [162513.515680] task:fsstress state:D stack: 0 pid:1356184 ppid:1356177 flags:0x00004000 [162513.515682] Call Trace: [162513.515688] __schedule+0x5ce/0xd00 [162513.515691] ? _raw_spin_unlock_irqrestore+0x3c/0x60 [162513.515697] schedule+0x46/0xf0 [162513.515712] wait_current_trans+0xde/0x140 [btrfs] [162513.515716] ? finish_wait+0x90/0x90 [162513.515729] start_transaction+0x37c/0x5f0 [btrfs] [162513.515743] btrfs_attach_transaction_barrier+0x1f/0x50 [btrfs] [162513.515753] btrfs_sync_fs+0x61/0x1c0 [btrfs] [162513.515758] ? __ia32_sys_fdatasync+0x20/0x20 [162513.515761] iterate_supers+0x87/0xf0 [162513.515765] ksys_sync+0x60/0xb0 [162513.515768] __do_sys_sync+0xa/0x10 [162513.515771] do_syscall_64+0x33/0x80 [162513.515774] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [162513.515781] RIP: 0033:0x7f5238f50bd7 [162513.515782] Code: Bad RIP value. [162513.515784] RSP: 002b:00007fff67b978e8 EFLAGS: 00000206 ORIG_RAX: 00000000000000a2 [162513.515786] RAX: ffffffffffffffda RBX: 000055b1fad2c560 RCX: 00007f5238f50bd7 [162513.515788] RDX: 00000000ffffffff RSI: 000000000daf0e74 RDI: 000000000000003a [162513.515789] RBP: 0000000000000032 R08: 000000000000000a R09: 00007f5239019be0 [162513.515791] R10: fffffffffffff24f R11: 0000000000000206 R12: 000000000000003a [162513.515792] R13: 00007fff67b97950 R14: 00007fff67b97906 R15: 000055b1fad1a340 [162513.515804] INFO: task fsstress:1356185 blocked for more than 120 seconds. [162513.516064] Not tainted 5.9.0-rc6-btrfs-next-69 #1 [162513.516329] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [162513.516617] task:fsstress state:D stack: 0 pid:1356185 ppid:1356177 flags:0x00000000 [162513.516620] Call Trace: [162513.516625] __schedule+0x5ce/0xd00 [162513.516628] ? _raw_spin_unlock_irqrestore+0x3c/0x60 [162513.516634] schedule+0x46/0xf0 [162513.516647] wait_current_trans+0xde/0x140 [btrfs] [162513.516650] ? finish_wait+0x90/0x90 [162513.516662] start_transaction+0x4d7/0x5f0 [btrfs] [162513.516679] btrfs_setxattr_trans+0x3c/0x100 [btrfs] [162513.516686] __vfs_setxattr+0x66/0x80 [162513.516691] __vfs_setxattr_noperm+0x70/0x200 [162513.516697] vfs_setxattr+0x6b/0x120 [162513.516703] setxattr+0x125/0x240 [162513.516709] ? lock_acquire+0xb1/0x480 [162513.516712] ? mnt_want_write+0x20/0x50 [162513.516721] ? rcu_read_lock_any_held+0x8e/0xb0 [162513.516723] ? preempt_count_add+0x49/0xa0 [162513.516725] ? __sb_start_write+0x19b/0x290 [162513.516727] ? preempt_count_add+0x49/0xa0 [162513.516732] path_setxattr+0xba/0xd0 [162513.516739] __x64_sys_setxattr+0x27/0x30 [162513.516741] do_syscall_64+0x33/0x80 [162513.516743] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [162513.516745] RIP: 0033:0x7f5238f56d5a [162513.516746] Code: Bad RIP value. [162513.516748] RSP: 002b:00007fff67b97868 EFLAGS: 00000202 ORIG_RAX: 00000000000000bc [162513.516750] RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 00007f5238f56d5a [162513.516751] RDX: 000055b1fbb0d5a0 RSI: 00007fff67b978a0 RDI: 000055b1fbb0d470 [162513.516753] RBP: 000055b1fbb0d5a0 R08: 0000000000000001 R09: 00007fff67b97700 [162513.516754] R10: 0000000000000004 R11: 0000000000000202 R12: 0000000000000004 [162513.516756] R13: 0000000000000024 R14: 0000000000000001 R15: 00007fff67b978a0 [162513.516767] INFO: task fsstress:1356196 blocked for more than 120 seconds. [162513.517064] Not tainted 5.9.0-rc6-btrfs-next-69 #1 [162513.517365] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [162513.517763] task:fsstress state:D stack: 0 pid:1356196 ppid:1356177 flags:0x00004000 [162513.517780] Call Trace: [162513.517786] __schedule+0x5ce/0xd00 [162513.517789] ? _raw_spin_unlock_irqrestore+0x3c/0x60 [162513.517796] schedule+0x46/0xf0 [162513.517810] wait_current_trans+0xde/0x140 [btrfs] [162513.517814] ? finish_wait+0x90/0x90 [162513.517829] start_transaction+0x37c/0x5f0 [btrfs] [162513.517845] btrfs_attach_transaction_barrier+0x1f/0x50 [btrfs] [162513.517857] btrfs_sync_fs+0x61/0x1c0 [btrfs] [162513.517862] ? __ia32_sys_fdatasync+0x20/0x20 [162513.517865] iterate_supers+0x87/0xf0 [162513.517869] ksys_sync+0x60/0xb0 [162513.517872] __do_sys_sync+0xa/0x10 [162513.517875] do_syscall_64+0x33/0x80 [162513.517878] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [162513.517881] RIP: 0033:0x7f5238f50bd7 [162513.517883] Code: Bad RIP value. [162513.517885] RSP: 002b:00007fff67b978e8 EFLAGS: 00000206 ORIG_RAX: 00000000000000a2 [162513.517887] RAX: ffffffffffffffda RBX: 000055b1fad2c560 RCX: 00007f5238f50bd7 [162513.517889] RDX: 0000000000000000 RSI: 000000007660add2 RDI: 0000000000000053 [162513.517891] RBP: 0000000000000032 R08: 0000000000000067 R09: 00007f5239019be0 [162513.517893] R10: fffffffffffff24f R11: 0000000000000206 R12: 0000000000000053 [162513.517895] R13: 00007fff67b97950 R14: 00007fff67b97906 R15: 000055b1fad1a340 [162513.517908] INFO: task fsstress:1356197 blocked for more than 120 seconds. [162513.518298] Not tainted 5.9.0-rc6-btrfs-next-69 #1 [162513.518672] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [162513.519157] task:fsstress state:D stack: 0 pid:1356197 ppid:1356177 flags:0x00000000 [162513.519160] Call Trace: [162513.519165] __schedule+0x5ce/0xd00 [162513.519168] ? _raw_spin_unlock_irqrestore+0x3c/0x60 [162513.519174] schedule+0x46/0xf0 [162513.519190] wait_current_trans+0xde/0x140 [btrfs] [162513.519193] ? finish_wait+0x90/0x90 [162513.519206] start_transaction+0x4d7/0x5f0 [btrfs] [162513.519222] btrfs_create+0x57/0x200 [btrfs] [162513.519230] lookup_open+0x522/0x650 [162513.519246] path_openat+0x2b8/0xa50 [162513.519270] do_filp_open+0x91/0x100 [162513.519275] ? find_held_lock+0x32/0x90 [162513.519280] ? lock_acquired+0x33b/0x470 [162513.519285] ? do_raw_spin_unlock+0x4b/0xc0 [162513.519287] ? _raw_spin_unlock+0x29/0x40 [162513.519295] do_sys_openat2+0x20d/0x2d0 [162513.519300] do_sys_open+0x44/0x80 [162513.519304] do_syscall_64+0x33/0x80 [162513.519307] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [162513.519309] RIP: 0033:0x7f5238f4a903 [162513.519310] Code: Bad RIP value. [162513.519312] RSP: 002b:00007fff67b97758 EFLAGS: 00000246 ORIG_RAX: 0000000000000055 [162513.519314] RAX: ffffffffffffffda RBX: 00000000ffffffff RCX: 00007f5238f4a903 [162513.519316] RDX: 0000000000000000 RSI: 00000000000001b6 RDI: 000055b1fbb0d470 [162513.519317] RBP: 00007fff67b978c0 R08: 0000000000000001 R09: 0000000000000002 [162513.519319] R10: 00007fff67b974f7 R11: 0000000000000246 R12: 0000000000000013 [162513.519320] R13: 00000000000001b6 R14: 00007fff67b97906 R15: 000055b1fad1c620 [162513.519332] INFO: task btrfs:1356211 blocked for more than 120 seconds. [162513.519727] Not tainted 5.9.0-rc6-btrfs-next-69 #1 [162513.520115] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [162513.520508] task:btrfs state:D stack: 0 pid:1356211 ppid:1356178 flags:0x00004002 [162513.520511] Call Trace: [162513.520516] __schedule+0x5ce/0xd00 [162513.520519] ? _raw_spin_unlock_irqrestore+0x3c/0x60 [162513.520525] schedule+0x46/0xf0 [162513.520544] btrfs_scrub_pause+0x11f/0x180 [btrfs] [162513.520548] ? finish_wait+0x90/0x90 [162513.520562] btrfs_commit_transaction+0x45a/0xc30 [btrfs] [162513.520574] ? start_transaction+0xe0/0x5f0 [btrfs] [162513.520596] btrfs_dev_replace_finishing+0x6d8/0x711 [btrfs] [162513.520619] btrfs_dev_replace_by_ioctl.cold+0x1cc/0x1fd [btrfs] [162513.520639] btrfs_ioctl+0x2a25/0x36f0 [btrfs] [162513.520643] ? do_sigaction+0xf3/0x240 [162513.520645] ? find_held_lock+0x32/0x90 [162513.520648] ? do_sigaction+0xf3/0x240 [162513.520651] ? lock_acquired+0x33b/0x470 [162513.520655] ? _raw_spin_unlock_irq+0x24/0x50 [162513.520657] ? lockdep_hardirqs_on+0x7d/0x100 [162513.520660] ? _raw_spin_unlock_irq+0x35/0x50 [162513.520662] ? do_sigaction+0xf3/0x240 [162513.520671] ? __x64_sys_ioctl+0x83/0xb0 [162513.520672] __x64_sys_ioctl+0x83/0xb0 [162513.520677] do_syscall_64+0x33/0x80 [162513.520679] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [162513.520681] RIP: 0033:0x7fc3cd307d87 [162513.520682] Code: Bad RIP value. [162513.520684] RSP: 002b:00007ffe30a56bb8 EFLAGS: 00000202 ORIG_RAX: 0000000000000010 [162513.520686] RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 00007fc3cd307d87 [162513.520687] RDX: 00007ffe30a57a30 RSI: 00000000ca289435 RDI: 0000000000000003 [162513.520689] RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 [162513.520690] R10: 0000000000000008 R11: 0000000000000202 R12: 0000000000000003 [162513.520692] R13: 0000557323a212e0 R14: 00007ffe30a5a520 R15: 0000000000000001 [162513.520703] Showing all locks held in the system: [162513.520712] 1 lock held by khungtaskd/54: [162513.520713] #0: ffffffffb40a91a0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x15/0x197 [162513.520728] 1 lock held by in:imklog/596: [162513.520729] #0: ffff8f3f0d781400 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x4d/0x60 [162513.520782] 1 lock held by btrfs-transacti/1356167: [162513.520784] #0: ffff8f3d810cc848 (&fs_info->transaction_kthread_mutex){+.+.}-{3:3}, at: transaction_kthread+0x4a/0x170 [btrfs] [162513.520798] 1 lock held by btrfs/1356190: [162513.520800] #0: ffff8f3d57644470 (sb_writers#15){.+.+}-{0:0}, at: mnt_want_write_file+0x22/0x60 [162513.520805] 1 lock held by fsstress/1356184: [162513.520806] #0: ffff8f3d576440e8 (&type->s_umount_key#62){++++}-{3:3}, at: iterate_supers+0x6f/0xf0 [162513.520811] 3 locks held by fsstress/1356185: [162513.520812] #0: ffff8f3d57644470 (sb_writers#15){.+.+}-{0:0}, at: mnt_want_write+0x20/0x50 [162513.520815] #1: ffff8f3d80a650b8 (&type->i_mutex_dir_key#10){++++}-{3:3}, at: vfs_setxattr+0x50/0x120 [162513.520820] #2: ffff8f3d57644690 (sb_internal#2){.+.+}-{0:0}, at: start_transaction+0x40e/0x5f0 [btrfs] [162513.520833] 1 lock held by fsstress/1356196: [162513.520834] #0: ffff8f3d576440e8 (&type->s_umount_key#62){++++}-{3:3}, at: iterate_supers+0x6f/0xf0 [162513.520838] 3 locks held by fsstress/1356197: [162513.520839] #0: ffff8f3d57644470 (sb_writers#15){.+.+}-{0:0}, at: mnt_want_write+0x20/0x50 [162513.520843] #1: ffff8f3d506465e8 (&type->i_mutex_dir_key#10){++++}-{3:3}, at: path_openat+0x2a7/0xa50 [162513.520846] #2: ffff8f3d57644690 (sb_internal#2){.+.+}-{0:0}, at: start_transaction+0x40e/0x5f0 [btrfs] [162513.520858] 2 locks held by btrfs/1356211: [162513.520859] #0: ffff8f3d810cde30 (&fs_info->dev_replace.lock_finishing_cancel_unmount){+.+.}-{3:3}, at: btrfs_dev_replace_finishing+0x52/0x711 [btrfs] [162513.520877] #1: ffff8f3d57644690 (sb_internal#2){.+.+}-{0:0}, at: start_transaction+0x40e/0x5f0 [btrfs] This was weird because the stack traces show that a transaction commit, triggered by a device replace operation, is blocking trying to pause any running scrubs but there are no stack traces of blocked tasks doing a scrub. After poking around with drgn, I noticed there was a scrub task that was constantly running and blocking for shorts periods of time: >>> t = find_task(prog, 1356190) >>> prog.stack_trace(t) #0 __schedule+0x5ce/0xcfc #1 schedule+0x46/0xe4 #2 schedule_timeout+0x1df/0x475 #3 btrfs_reada_wait+0xda/0x132 #4 scrub_stripe+0x2a8/0x112f #5 scrub_chunk+0xcd/0x134 #6 scrub_enumerate_chunks+0x29e/0x5ee #7 btrfs_scrub_dev+0x2d5/0x91b #8 btrfs_ioctl+0x7f5/0x36e7 #9 __x64_sys_ioctl+0x83/0xb0 #10 do_syscall_64+0x33/0x77 #11 entry_SYSCALL_64+0x7c/0x156 Which corresponds to: int btrfs_reada_wait(void *handle) { struct reada_control *rc = handle; struct btrfs_fs_info *fs_info = rc->fs_info; while (atomic_read(&rc->elems)) { if (!atomic_read(&fs_info->reada_works_cnt)) reada_start_machine(fs_info); wait_event_timeout(rc->wait, atomic_read(&rc->elems) == 0, (HZ + 9) / 10); } (...) So the counter "rc->elems" was set to 1 and never decreased to 0, causing the scrub task to loop forever in that function. Then I used the following script for drgn to check the readahead requests: $ cat dump_reada.py import sys import drgn from drgn import NULL, Object, cast, container_of, execscript, \ reinterpret, sizeof from drgn.helpers.linux import * mnt_path = b"/home/fdmanana/btrfs-tests/scratch_1" mnt = None for mnt in for_each_mount(prog, dst = mnt_path): pass if mnt is None: sys.stderr.write(f'Error: mount point {mnt_path} not found\n') sys.exit(1) fs_info = cast('struct btrfs_fs_info *', mnt.mnt.mnt_sb.s_fs_info) def dump_re(re): nzones = re.nzones.value_() print(f're at {hex(re.value_())}') print(f'\t logical {re.logical.value_()}') print(f'\t refcnt {re.refcnt.value_()}') print(f'\t nzones {nzones}') for i in range(nzones): dev = re.zones[i].device name = dev.name.str.string_() print(f'\t\t dev id {dev.devid.value_()} name {name}') print() for _, e in radix_tree_for_each(fs_info.reada_tree): re = cast('struct reada_extent *', e) dump_re(re) $ drgn dump_reada.py re at 0xffff8f3da9d25ad8 logical 38928384 refcnt 1 nzones 1 dev id 0 name b'/dev/sdd' $ So there was one readahead extent with a single zone corresponding to the source device of that last device replace operation logged in dmesg/syslog. Also the ID of that zone's device was 0 which is a special value set in the source device of a device replace operation when the operation finishes (constant BTRFS_DEV_REPLACE_DEVID set at btrfs_dev_replace_finishing()), confirming again that device /dev/sdd was the source of a device replace operation. Normally there should be as many zones in the readahead extent as there are devices, and I wasn't expecting the extent to be in a block group with a 'single' profile, so I went and confirmed with the following drgn script that there weren't any single profile block groups: $ cat dump_block_groups.py import sys import drgn from drgn import NULL, Object, cast, container_of, execscript, \ reinterpret, sizeof from drgn.helpers.linux import * mnt_path = b"/home/fdmanana/btrfs-tests/scratch_1" mnt = None for mnt in for_each_mount(prog, dst = mnt_path): pass if mnt is None: sys.stderr.write(f'Error: mount point {mnt_path} not found\n') sys.exit(1) fs_info = cast('struct btrfs_fs_info *', mnt.mnt.mnt_sb.s_fs_info) BTRFS_BLOCK_GROUP_DATA = (1 << 0) BTRFS_BLOCK_GROUP_SYSTEM = (1 << 1) BTRFS_BLOCK_GROUP_METADATA = (1 << 2) BTRFS_BLOCK_GROUP_RAID0 = (1 << 3) BTRFS_BLOCK_GROUP_RAID1 = (1 << 4) BTRFS_BLOCK_GROUP_DUP = (1 << 5) BTRFS_BLOCK_GROUP_RAID10 = (1 << 6) BTRFS_BLOCK_GROUP_RAID5 = (1 << 7) BTRFS_BLOCK_GROUP_RAID6 = (1 << 8) BTRFS_BLOCK_GROUP_RAID1C3 = (1 << 9) BTRFS_BLOCK_GROUP_RAID1C4 = (1 << 10) def bg_flags_string(bg): flags = bg.flags.value_() ret = '' if flags & BTRFS_BLOCK_GROUP_DATA: ret = 'data' if flags & BTRFS_BLOCK_GROUP_METADATA: if len(ret) > 0: ret += '|' ret += 'meta' if flags & BTRFS_BLOCK_GROUP_SYSTEM: if len(ret) > 0: ret += '|' ret += 'system' if flags & BTRFS_BLOCK_GROUP_RAID0: ret += ' raid0' elif flags & BTRFS_BLOCK_GROUP_RAID1: ret += ' raid1' elif flags & BTRFS_BLOCK_GROUP_DUP: ret += ' dup' elif flags & BTRFS_BLOCK_GROUP_RAID10: ret += ' raid10' elif flags & BTRFS_BLOCK_GROUP_RAID5: ret += ' raid5' elif flags & BTRFS_BLOCK_GROUP_RAID6: ret += ' raid6' elif flags & BTRFS_BLOCK_GROUP_RAID1C3: ret += ' raid1c3' elif flags & BTRFS_BLOCK_GROUP_RAID1C4: ret += ' raid1c4' else: ret += ' single' return ret def dump_bg(bg): print() print(f'block group at {hex(bg.value_())}') print(f'\t start {bg.start.value_()} length {bg.length.value_()}') print(f'\t flags {bg.flags.value_()} - {bg_flags_string(bg)}') bg_root = fs_info.block_group_cache_tree.address_of_() for bg in rbtree_inorder_for_each_entry('struct btrfs_block_group', bg_root, 'cache_node'): dump_bg(bg) $ drgn dump_block_groups.py block group at 0xffff8f3d673b0400 start 22020096 length 16777216 flags 258 - system raid6 block group at 0xffff8f3d53ddb400 start 38797312 length 536870912 flags 260 - meta raid6 block group at 0xffff8f3d5f4d9c00 start 575668224 length 2147483648 flags 257 - data raid6 block group at 0xffff8f3d08189000 start 2723151872 length 67108864 flags 258 - system raid6 block group at 0xffff8f3db70ff000 start 2790260736 length 1073741824 flags 260 - meta raid6 block group at 0xffff8f3d5f4dd800 start 3864002560 length 67108864 flags 258 - system raid6 block group at 0xffff8f3d67037000 start 3931111424 length 2147483648 flags 257 - data raid6 $ So there were only 2 reasons left for having a readahead extent with a single zone: reada_find_zone(), called when creating a readahead extent, returned NULL either because we failed to find the corresponding block group or because a memory allocation failed. With some additional and custom tracing I figured out that on every further ocurrence of the problem the block group had just been deleted when we were looping to create the zones for the readahead extent (at reada_find_extent()), so we ended up with only one zone in the readahead extent, corresponding to a device that ends up getting replaced. So after figuring that out it became obvious why the hang happens: 1) Task A starts a scrub on any device of the filesystem, except for device /dev/sdd; 2) Task B starts a device replace with /dev/sdd as the source device; 3) Task A calls btrfs_reada_add() from scrub_stripe() and it is currently starting to scrub a stripe from block group X. This call to btrfs_reada_add() is the one for the extent tree. When btrfs_reada_add() calls reada_add_block(), it passes the logical address of the extent tree's root node as its 'logical' argument - a value of 38928384; 4) Task A then enters reada_find_extent(), called from reada_add_block(). It finds there isn't any existing readahead extent for the logical address 38928384, so it proceeds to the path of creating a new one. It calls btrfs_map_block() to find out which stripes exist for the block group X. On the first iteration of the for loop that iterates over the stripes, it finds the stripe for device /dev/sdd, so it creates one zone for that device and adds it to the readahead extent. Before getting into the second iteration of the loop, the cleanup kthread deletes block group X because it was empty. So in the iterations for the remaining stripes it does not add more zones to the readahead extent, because the calls to reada_find_zone() returned NULL because they couldn't find block group X anymore. As a result the new readahead extent has a single zone, corresponding to the device /dev/sdd; 4) Before task A returns to btrfs_reada_add() and queues the readahead job for the readahead work queue, task B finishes the device replace and at btrfs_dev_replace_finishing() swaps the device /dev/sdd with the new device /dev/sdg; 5) Task A returns to reada_add_block(), which increments the counter "->elems" of the reada_control structure allocated at btrfs_reada_add(). Then it returns back to btrfs_reada_add() and calls reada_start_machine(). This queues a job in the readahead work queue to run the function reada_start_machine_worker(), which calls __reada_start_machine(). At __reada_start_machine() we take the device list mutex and for each device found in the current device list, we call reada_start_machine_dev() to start the readahead work. However at this point the device /dev/sdd was already freed and is not in the device list anymore. This means the corresponding readahead for the extent at 38928384 is never started, and therefore the "->elems" counter of the reada_control structure allocated at btrfs_reada_add() never goes down to 0, causing the call to btrfs_reada_wait(), done by the scrub task, to wait forever. Note that the readahead request can be made either after the device replace started or before it started, however in pratice it is very unlikely that a device replace is able to start after a readahead request is made and is able to complete before the readahead request completes - maybe only on a very small and nearly empty filesystem. This hang however is not the only problem we can have with readahead and device removals. When the readahead extent has other zones other than the one corresponding to the device that is being removed (either by a device replace or a device remove operation), we risk having a use-after-free on the device when dropping the last reference of the readahead extent. For example if we create a readahead extent with two zones, one for the device /dev/sdd and one for the device /dev/sde: 1) Before the readahead worker starts, the device /dev/sdd is removed, and the corresponding btrfs_device structure is freed. However the readahead extent still has the zone pointing to the device structure; 2) When the readahead worker starts, it only finds device /dev/sde in the current device list of the filesystem; 3) It starts the readahead work, at reada_start_machine_dev(), using the device /dev/sde; 4) Then when it finishes reading the extent from device /dev/sde, it calls __readahead_hook() which ends up dropping the last reference on the readahead extent through the last call to reada_extent_put(); 5) At reada_extent_put() it iterates over each zone of the readahead extent and attempts to delete an element from the device's 'reada_extents' radix tree, resulting in a use-after-free, as the device pointer of the zone for /dev/sdd is now stale. We can also access the device after dropping the last reference of a zone, through reada_zone_release(), also called by reada_extent_put(). And a device remove suffers the same problem, however since it shrinks the device size down to zero before removing the device, it is very unlikely to still have readahead requests not completed by the time we free the device, the only possibility is if the device has a very little space allocated. While the hang problem is exclusive to scrub, since it is currently the only user of btrfs_reada_add() and btrfs_reada_wait(), the use-after-free problem affects any path that triggers readhead, which includes btree_readahead_hook() and __readahead_hook() (a readahead worker can trigger readahed for the children of a node) for example - any path that ends up calling reada_add_block() can trigger the use-after-free after a device is removed. So fix this by waiting for any readahead requests for a device to complete before removing a device, ensuring that while waiting for existing ones no new ones can be made. This problem has been around for a very long time - the readahead code was added in 2011, device remove exists since 2008 and device replace was introduced in 2013, hard to pick a specific commit for a git Fixes tag. CC: stable@vger.kernel.org # 4.4+ Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>

This fix is for a failure that occurred in the DWARF unwind perf test. Stack unwinders may probe memory when looking for frames. Memory sanitizer will poison and track uninitialized memory on the stack, and on the heap if the value is copied to the heap. This can lead to false memory sanitizer failures for the use of an uninitialized value. Avoid this problem by removing the poison on the copied stack. The full msan failure with track origins looks like: ==2168==WARNING: MemorySanitizer: use-of-uninitialized-value #0 0x559ceb10755b in handle_cfi elfutils/libdwfl/frame_unwind.c:648:8 #1 0x559ceb105448 in __libdwfl_frame_unwind elfutils/libdwfl/frame_unwind.c:741:4 #2 0x559ceb0ece90 in dwfl_thread_getframes elfutils/libdwfl/dwfl_frame.c:435:7 #3 0x559ceb0ec6b7 in get_one_thread_frames_cb elfutils/libdwfl/dwfl_frame.c:379:10 #4 0x559ceb0ec6b7 in get_one_thread_cb elfutils/libdwfl/dwfl_frame.c:308:17 #5 0x559ceb0ec6b7 in dwfl_getthreads elfutils/libdwfl/dwfl_frame.c:283:17 #6 0x559ceb0ec6b7 in getthread elfutils/libdwfl/dwfl_frame.c:354:14 #7 0x559ceb0ec6b7 in dwfl_getthread_frames elfutils/libdwfl/dwfl_frame.c:388:10 #8 0x559ceaff6ae6 in unwind__get_entries tools/perf/util/unwind-libdw.c:236:8 #9 0x559ceabc9dbc in test_dwarf_unwind__thread tools/perf/tests/dwarf-unwind.c:111:8 #10 0x559ceabca5cf in test_dwarf_unwind__compare tools/perf/tests/dwarf-unwind.c:138:26 #11 0x7f812a6865b0 in bsearch (libc.so.6+0x4e5b0) #12 0x559ceabca871 in test_dwarf_unwind__krava_3 tools/perf/tests/dwarf-unwind.c:162:2 #13 0x559ceabca926 in test_dwarf_unwind__krava_2 tools/perf/tests/dwarf-unwind.c:169:9 #14 0x559ceabca946 in test_dwarf_unwind__krava_1 tools/perf/tests/dwarf-unwind.c:174:9 #15 0x559ceabcae12 in test__dwarf_unwind tools/perf/tests/dwarf-unwind.c:211:8 #16 0x559ceabbc4ab in run_test tools/perf/tests/builtin-test.c:418:9 #17 0x559ceabbc4ab in test_and_print tools/perf/tests/builtin-test.c:448:9 #18 0x559ceabbac70 in __cmd_test tools/perf/tests/builtin-test.c:669:4 #19 0x559ceabbac70 in cmd_test tools/perf/tests/builtin-test.c:815:9 #20 0x559cea960e30 in run_builtin tools/perf/perf.c:313:11 #21 0x559cea95fbce in handle_internal_command tools/perf/perf.c:365:8 #22 0x559cea95fbce in run_argv tools/perf/perf.c:409:2 #23 0x559cea95fbce in main tools/perf/perf.c:539:3 Uninitialized value was stored to memory at #0 0x559ceb106acf in __libdwfl_frame_reg_set elfutils/libdwfl/frame_unwind.c:77:22 #1 0x559ceb106acf in handle_cfi elfutils/libdwfl/frame_unwind.c:627:13 #2 0x559ceb105448 in __libdwfl_frame_unwind elfutils/libdwfl/frame_unwind.c:741:4 #3 0x559ceb0ece90 in dwfl_thread_getframes elfutils/libdwfl/dwfl_frame.c:435:7 #4 0x559ceb0ec6b7 in get_one_thread_frames_cb elfutils/libdwfl/dwfl_frame.c:379:10 #5 0x559ceb0ec6b7 in get_one_thread_cb elfutils/libdwfl/dwfl_frame.c:308:17 #6 0x559ceb0ec6b7 in dwfl_getthreads elfutils/libdwfl/dwfl_frame.c:283:17 #7 0x559ceb0ec6b7 in getthread elfutils/libdwfl/dwfl_frame.c:354:14 #8 0x559ceb0ec6b7 in dwfl_getthread_frames elfutils/libdwfl/dwfl_frame.c:388:10 #9 0x559ceaff6ae6 in unwind__get_entries tools/perf/util/unwind-libdw.c:236:8 #10 0x559ceabc9dbc in test_dwarf_unwind__thread tools/perf/tests/dwarf-unwind.c:111:8 #11 0x559ceabca5cf in test_dwarf_unwind__compare tools/perf/tests/dwarf-unwind.c:138:26 #12 0x7f812a6865b0 in bsearch (libc.so.6+0x4e5b0) #13 0x559ceabca871 in test_dwarf_unwind__krava_3 tools/perf/tests/dwarf-unwind.c:162:2 #14 0x559ceabca926 in test_dwarf_unwind__krava_2 tools/perf/tests/dwarf-unwind.c:169:9 #15 0x559ceabca946 in test_dwarf_unwind__krava_1 tools/perf/tests/dwarf-unwind.c:174:9 #16 0x559ceabcae12 in test__dwarf_unwind tools/perf/tests/dwarf-unwind.c:211:8 #17 0x559ceabbc4ab in run_test tools/perf/tests/builtin-test.c:418:9 #18 0x559ceabbc4ab in test_and_print tools/perf/tests/builtin-test.c:448:9 #19 0x559ceabbac70 in __cmd_test tools/perf/tests/builtin-test.c:669:4 #20 0x559ceabbac70 in cmd_test tools/perf/tests/builtin-test.c:815:9 #21 0x559cea960e30 in run_builtin tools/perf/perf.c:313:11 #22 0x559cea95fbce in handle_internal_command tools/perf/perf.c:365:8 #23 0x559cea95fbce in run_argv tools/perf/perf.c:409:2 #24 0x559cea95fbce in main tools/perf/perf.c:539:3 Uninitialized value was stored to memory at #0 0x559ceb106a54 in handle_cfi elfutils/libdwfl/frame_unwind.c:613:9 #1 0x559ceb105448 in __libdwfl_frame_unwind elfutils/libdwfl/frame_unwind.c:741:4 #2 0x559ceb0ece90 in dwfl_thread_getframes elfutils/libdwfl/dwfl_frame.c:435:7 #3 0x559ceb0ec6b7 in get_one_thread_frames_cb elfutils/libdwfl/dwfl_frame.c:379:10 #4 0x559ceb0ec6b7 in get_one_thread_cb elfutils/libdwfl/dwfl_frame.c:308:17 #5 0x559ceb0ec6b7 in dwfl_getthreads elfutils/libdwfl/dwfl_frame.c:283:17 #6 0x559ceb0ec6b7 in getthread elfutils/libdwfl/dwfl_frame.c:354:14 #7 0x559ceb0ec6b7 in dwfl_getthread_frames elfutils/libdwfl/dwfl_frame.c:388:10 #8 0x559ceaff6ae6 in unwind__get_entries tools/perf/util/unwind-libdw.c:236:8 #9 0x559ceabc9dbc in test_dwarf_unwind__thread tools/perf/tests/dwarf-unwind.c:111:8 #10 0x559ceabca5cf in test_dwarf_unwind__compare tools/perf/tests/dwarf-unwind.c:138:26 #11 0x7f812a6865b0 in bsearch (libc.so.6+0x4e5b0) #12 0x559ceabca871 in test_dwarf_unwind__krava_3 tools/perf/tests/dwarf-unwind.c:162:2 #13 0x559ceabca926 in test_dwarf_unwind__krava_2 tools/perf/tests/dwarf-unwind.c:169:9 #14 0x559ceabca946 in test_dwarf_unwind__krava_1 tools/perf/tests/dwarf-unwind.c:174:9 #15 0x559ceabcae12 in test__dwarf_unwind tools/perf/tests/dwarf-unwind.c:211:8 #16 0x559ceabbc4ab in run_test tools/perf/tests/builtin-test.c:418:9 #17 0x559ceabbc4ab in test_and_print tools/perf/tests/builtin-test.c:448:9 #18 0x559ceabbac70 in __cmd_test tools/perf/tests/builtin-test.c:669:4 #19 0x559ceabbac70 in cmd_test tools/perf/tests/builtin-test.c:815:9 #20 0x559cea960e30 in run_builtin tools/perf/perf.c:313:11 #21 0x559cea95fbce in handle_internal_command tools/perf/perf.c:365:8 #22 0x559cea95fbce in run_argv tools/perf/perf.c:409:2 #23 0x559cea95fbce in main tools/perf/perf.c:539:3 Uninitialized value was stored to memory at #0 0x559ceaff8800 in memory_read tools/perf/util/unwind-libdw.c:156:10 #1 0x559ceb10f053 in expr_eval elfutils/libdwfl/frame_unwind.c:501:13 #2 0x559ceb1060cc in handle_cfi elfutils/libdwfl/frame_unwind.c:603:18 #3 0x559ceb105448 in __libdwfl_frame_unwind elfutils/libdwfl/frame_unwind.c:741:4 #4 0x559ceb0ece90 in dwfl_thread_getframes elfutils/libdwfl/dwfl_frame.c:435:7 #5 0x559ceb0ec6b7 in get_one_thread_frames_cb elfutils/libdwfl/dwfl_frame.c:379:10 #6 0x559ceb0ec6b7 in get_one_thread_cb elfutils/libdwfl/dwfl_frame.c:308:17 #7 0x559ceb0ec6b7 in dwfl_getthreads elfutils/libdwfl/dwfl_frame.c:283:17 #8 0x559ceb0ec6b7 in getthread elfutils/libdwfl/dwfl_frame.c:354:14 #9 0x559ceb0ec6b7 in dwfl_getthread_frames elfutils/libdwfl/dwfl_frame.c:388:10 #10 0x559ceaff6ae6 in unwind__get_entries tools/perf/util/unwind-libdw.c:236:8 #11 0x559ceabc9dbc in test_dwarf_unwind__thread tools/perf/tests/dwarf-unwind.c:111:8 #12 0x559ceabca5cf in test_dwarf_unwind__compare tools/perf/tests/dwarf-unwind.c:138:26 #13 0x7f812a6865b0 in bsearch (libc.so.6+0x4e5b0) #14 0x559ceabca871 in test_dwarf_unwind__krava_3 tools/perf/tests/dwarf-unwind.c:162:2 #15 0x559ceabca926 in test_dwarf_unwind__krava_2 tools/perf/tests/dwarf-unwind.c:169:9 #16 0x559ceabca946 in test_dwarf_unwind__krava_1 tools/perf/tests/dwarf-unwind.c:174:9 #17 0x559ceabcae12 in test__dwarf_unwind tools/perf/tests/dwarf-unwind.c:211:8 #18 0x559ceabbc4ab in run_test tools/perf/tests/builtin-test.c:418:9 #19 0x559ceabbc4ab in test_and_print tools/perf/tests/builtin-test.c:448:9 #20 0x559ceabbac70 in __cmd_test tools/perf/tests/builtin-test.c:669:4 #21 0x559ceabbac70 in cmd_test tools/perf/tests/builtin-test.c:815:9 #22 0x559cea960e30 in run_builtin tools/perf/perf.c:313:11 #23 0x559cea95fbce in handle_internal_command tools/perf/perf.c:365:8 #24 0x559cea95fbce in run_argv tools/perf/perf.c:409:2 #25 0x559cea95fbce in main tools/perf/perf.c:539:3 Uninitialized value was stored to memory at #0 0x559cea9027d9 in __msan_memcpy llvm/llvm-project/compiler-rt/lib/msan/msan_interceptors.cpp:1558:3 #1 0x559cea9d2185 in sample_ustack tools/perf/arch/x86/tests/dwarf-unwind.c:41:2 #2 0x559cea9d202c in test__arch_unwind_sample tools/perf/arch/x86/tests/dwarf-unwind.c:72:9 #3 0x559ceabc9cbd in test_dwarf_unwind__thread tools/perf/tests/dwarf-unwind.c:106:6 #4 0x559ceabca5cf in test_dwarf_unwind__compare tools/perf/tests/dwarf-unwind.c:138:26 #5 0x7f812a6865b0 in bsearch (libc.so.6+0x4e5b0) #6 0x559ceabca871 in test_dwarf_unwind__krava_3 tools/perf/tests/dwarf-unwind.c:162:2 #7 0x559ceabca926 in test_dwarf_unwind__krava_2 tools/perf/tests/dwarf-unwind.c:169:9 #8 0x559ceabca946 in test_dwarf_unwind__krava_1 tools/perf/tests/dwarf-unwind.c:174:9 #9 0x559ceabcae12 in test__dwarf_unwind tools/perf/tests/dwarf-unwind.c:211:8 #10 0x559ceabbc4ab in run_test tools/perf/tests/builtin-test.c:418:9 #11 0x559ceabbc4ab in test_and_print tools/perf/tests/builtin-test.c:448:9 #12 0x559ceabbac70 in __cmd_test tools/perf/tests/builtin-test.c:669:4 #13 0x559ceabbac70 in cmd_test tools/perf/tests/builtin-test.c:815:9 #14 0x559cea960e30 in run_builtin tools/perf/perf.c:313:11 #15 0x559cea95fbce in handle_internal_command tools/perf/perf.c:365:8 #16 0x559cea95fbce in run_argv tools/perf/perf.c:409:2 #17 0x559cea95fbce in main tools/perf/perf.c:539:3 Uninitialized value was created by an allocation of 'bf' in the stack frame of function 'perf_event__synthesize_mmap_events' #0 0x559ceafc5f60 in perf_event__synthesize_mmap_events tools/perf/util/synthetic-events.c:445 SUMMARY: MemorySanitizer: use-of-uninitialized-value elfutils/libdwfl/frame_unwind.c:648:8 in handle_cfi Signed-off-by: Ian Rogers <irogers@google.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: clang-built-linux@googlegroups.com Cc: Jiri Olsa <jolsa@redhat.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Sandeep Dasgupta <sdasgup@google.com> Cc: Stephane Eranian <eranian@google.com> Link: http://lore.kernel.org/lkml/20201113182053.754625-1-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

We had kernel panic, it is caused by unload module and last close confirmation. call trace: [1196029.743127] free_sess+0x15/0x50 [rtrs_client] [1196029.743128] rtrs_clt_close+0x4c/0x70 [rtrs_client] [1196029.743129] ? rnbd_clt_unmap_device+0x1b0/0x1b0 [rnbd_client] [1196029.743130] close_rtrs+0x25/0x50 [rnbd_client] [1196029.743131] rnbd_client_exit+0x93/0xb99 [rnbd_client] [1196029.743132] __x64_sys_delete_module+0x190/0x260 And in the crashdump confirmation kworker is also running. PID: 6943 TASK: ffff9e2ac8098000 CPU: 4 COMMAND: "kworker/4:2" #0 [ffffb206cf337c30] __schedule at ffffffff9f93f891 #1 [ffffb206cf337cc8] schedule at ffffffff9f93fe98 #2 [ffffb206cf337cd0] schedule_timeout at ffffffff9f943938 #3 [ffffb206cf337d50] wait_for_completion at ffffffff9f9410a7 #4 [ffffb206cf337da0] __flush_work at ffffffff9f08ce0e #5 [ffffb206cf337e20] rtrs_clt_close_conns at ffffffffc0d5f668 [rtrs_client] #6 [ffffb206cf337e48] rtrs_clt_close at ffffffffc0d5f801 [rtrs_client] #7 [ffffb206cf337e68] close_rtrs at ffffffffc0d26255 [rnbd_client] #8 [ffffb206cf337e78] free_sess at ffffffffc0d262ad [rnbd_client] #9 [ffffb206cf337e88] rnbd_clt_put_dev at ffffffffc0d266a7 [rnbd_client] The problem is both code path try to close same session, which lead to panic. To fix it, just skip the sess if the refcount already drop to 0. Fixes: f7a7a5c ("block/rnbd: client: main functionality") Signed-off-by: Jack Wang <jinpu.wang@cloud.ionos.com> Reviewed-by: Gioh Kim <gi-oh.kim@cloud.ionos.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>

The bit that indicates if the device supports 160MHZ is bit #9. The macro checks bit #8. Fix IWL_SUBDEVICE_NO_160 macro to use the correct bit. Signed-off-by: Matti Gottlieb <matti.gottlieb@intel.com> Fixes: d6f2134 ("iwlwifi: add mac/rf types and 160MHz to the device tables") Signed-off-by: Luca Coelho <luciano.coelho@intel.com> Signed-off-by: Kalle Valo <kvalo@codeaurora.org> Link: https://lore.kernel.org/r/iwlwifi.20210122144849.bddbf9b57a75.I16e09e2b1404b16bfff70852a5a654aa468579e2@changeid

Calling btrfs_qgroup_reserve_meta_prealloc from btrfs_delayed_inode_reserve_metadata can result in flushing delalloc while holding a transaction and delayed node locks. This is deadlock prone. In the past multiple commits: * ae5e070 ("btrfs: qgroup: don't try to wait flushing if we're already holding a transaction") * 6f23277 ("btrfs: qgroup: don't commit transaction when we already hold the handle") Tried to solve various aspects of this but this was always a whack-a-mole game. Unfortunately those 2 fixes don't solve a deadlock scenario involving btrfs_delayed_node::mutex. Namely, one thread can call btrfs_dirty_inode as a result of reading a file and modifying its atime: PID: 6963 TASK: ffff8c7f3f94c000 CPU: 2 COMMAND: "test" #0 __schedule at ffffffffa529e07d #1 schedule at ffffffffa529e4ff #2 schedule_timeout at ffffffffa52a1bdd #3 wait_for_completion at ffffffffa529eeea <-- sleeps with delayed node mutex held #4 start_delalloc_inodes at ffffffffc0380db5 #5 btrfs_start_delalloc_snapshot at ffffffffc0393836 #6 try_flush_qgroup at ffffffffc03f04b2 #7 __btrfs_qgroup_reserve_meta at ffffffffc03f5bb6 <-- tries to reserve space and starts delalloc inodes. #8 btrfs_delayed_update_inode at ffffffffc03e31aa <-- acquires delayed node mutex #9 btrfs_update_inode at ffffffffc0385ba8 #10 btrfs_dirty_inode at ffffffffc038627b <-- TRANSACTIION OPENED #11 touch_atime at ffffffffa4cf0000 #12 generic_file_read_iter at ffffffffa4c1f123 #13 new_sync_read at ffffffffa4ccdc8a #14 vfs_read at ffffffffa4cd0849 #15 ksys_read at ffffffffa4cd0bd1 #16 do_syscall_64 at ffffffffa4a052eb #17 entry_SYSCALL_64_after_hwframe at ffffffffa540008c This will cause an asynchronous work to flush the delalloc inodes to happen which can try to acquire the same delayed_node mutex: PID: 455 TASK: ffff8c8085fa4000 CPU: 5 COMMAND: "kworker/u16:30" #0 __schedule at ffffffffa529e07d #1 schedule at ffffffffa529e4ff #2 schedule_preempt_disabled at ffffffffa529e80a #3 __mutex_lock at ffffffffa529fdcb <-- goes to sleep, never wakes up. #4 btrfs_delayed_update_inode at ffffffffc03e3143 <-- tries to acquire the mutex #5 btrfs_update_inode at ffffffffc0385ba8 <-- this is the same inode that pid 6963 is holding #6 cow_file_range_inline.constprop.78 at ffffffffc0386be7 #7 cow_file_range at ffffffffc03879c1 #8 btrfs_run_delalloc_range at ffffffffc038894c #9 writepage_delalloc at ffffffffc03a3c8f #10 __extent_writepage at ffffffffc03a4c01 #11 extent_write_cache_pages at ffffffffc03a500b #12 extent_writepages at ffffffffc03a6de2 #13 do_writepages at ffffffffa4c277eb #14 __filemap_fdatawrite_range at ffffffffa4c1e5bb #15 btrfs_run_delalloc_work at ffffffffc0380987 <-- starts running delayed nodes #16 normal_work_helper at ffffffffc03b706c #17 process_one_work at ffffffffa4aba4e4 #18 worker_thread at ffffffffa4aba6fd #19 kthread at ffffffffa4ac0a3d #20 ret_from_fork at ffffffffa54001ff To fully address those cases the complete fix is to never issue any flushing while holding the transaction or the delayed node lock. This patch achieves it by calling qgroup_reserve_meta directly which will either succeed without flushing or will fail and return -EDQUOT. In the latter case that return value is going to be propagated to btrfs_dirty_inode which will fallback to start a new transaction. That's fine as the majority of time we expect the inode will have BTRFS_DELAYED_NODE_INODE_DIRTY flag set which will result in directly copying the in-memory state. Fixes: c53e965 ("btrfs: qgroup: try to flush qgroup space when we get -EDQUOT") CC: stable@vger.kernel.org # 5.10+ Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: Nikolay Borisov <nborisov@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>

The evlist has the maps with its own refcounts so we don't need to set the pointers to NULL. Otherwise following error was reported by Asan. # perf test -v 4 4: Read samples using the mmap interface : --- start --- test child forked, pid 139782 mmap size 528384B ================================================================= ==139782==ERROR: LeakSanitizer: detected memory leaks Direct leak of 40 byte(s) in 1 object(s) allocated from: #0 0x7f1f76daee8f in __interceptor_malloc ../../../../src/libsanitizer/asan/asan_malloc_linux.cpp:145 #1 0x564ba21a0fea in cpu_map__trim_new /home/namhyung/project/linux/tools/lib/perf/cpumap.c:79 #2 0x564ba21a1a0f in perf_cpu_map__read /home/namhyung/project/linux/tools/lib/perf/cpumap.c:149 #3 0x564ba21a21cf in cpu_map__read_all_cpu_map /home/namhyung/project/linux/tools/lib/perf/cpumap.c:166 #4 0x564ba21a21cf in perf_cpu_map__new /home/namhyung/project/linux/tools/lib/perf/cpumap.c:181 #5 0x564ba1e48298 in test__basic_mmap tests/mmap-basic.c:55 #6 0x564ba1e278fb in run_test tests/builtin-test.c:428 #7 0x564ba1e278fb in test_and_print tests/builtin-test.c:458 #8 0x564ba1e29a53 in __cmd_test tests/builtin-test.c:679 #9 0x564ba1e29a53 in cmd_test tests/builtin-test.c:825 #10 0x564ba1e95cb4 in run_builtin /home/namhyung/project/linux/tools/perf/perf.c:313 #11 0x564ba1d1fa88 in handle_internal_command /home/namhyung/project/linux/tools/perf/perf.c:365 #12 0x564ba1d1fa88 in run_argv /home/namhyung/project/linux/tools/perf/perf.c:409 #13 0x564ba1d1fa88 in main /home/namhyung/project/linux/tools/perf/perf.c:539 #14 0x7f1f768e4d09 in __libc_start_main ../csu/libc-start.c:308 ... test child finished with 1 ---- end ---- Read samples using the mmap interface: FAILED! failed to open shell test directory: /home/namhyung/libexec/perf-core/tests/shell Signed-off-by: Namhyung Kim <namhyung@kernel.org> Acked-by: Jiri Olsa <jolsa@redhat.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Stephane Eranian <eranian@google.com> Cc: Ian Rogers <irogers@google.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Leo Yan <leo.yan@linaro.org> Cc: Andi Kleen <ak@linux.intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Link: https://lore.kernel.org/r/20210301140409.184570-2-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

The evlist has the maps with its own refcounts so we don't need to set the pointers to NULL. Otherwise following error was reported by Asan. Also change the goto label since it doesn't need to have two. # perf test -v 24 24: Number of exit events of a simple workload : --- start --- test child forked, pid 145915 mmap size 528384B ================================================================= ==145915==ERROR: LeakSanitizer: detected memory leaks Direct leak of 32 byte(s) in 1 object(s) allocated from: #0 0x7fc44e50d1f8 in __interceptor_realloc ../../../../src/libsanitizer/asan/asan_malloc_linux.cpp:164 #1 0x561cf50f4d2e in perf_thread_map__realloc /home/namhyung/project/linux/tools/lib/perf/threadmap.c:23 #2 0x561cf4eeb949 in thread_map__new_by_tid util/thread_map.c:63 #3 0x561cf4db7fd2 in test__task_exit tests/task-exit.c:74 #4 0x561cf4d798fb in run_test tests/builtin-test.c:428 #5 0x561cf4d798fb in test_and_print tests/builtin-test.c:458 #6 0x561cf4d7ba53 in __cmd_test tests/builtin-test.c:679 #7 0x561cf4d7ba53 in cmd_test tests/builtin-test.c:825 #8 0x561cf4de7d04 in run_builtin /home/namhyung/project/linux/tools/perf/perf.c:313 #9 0x561cf4c71a88 in handle_internal_command /home/namhyung/project/linux/tools/perf/perf.c:365 #10 0x561cf4c71a88 in run_argv /home/namhyung/project/linux/tools/perf/perf.c:409 #11 0x561cf4c71a88 in main /home/namhyung/project/linux/tools/perf/perf.c:539 #12 0x7fc44e042d09 in __libc_start_main ../csu/libc-start.c:308 ... test child finished with 1 ---- end ---- Number of exit events of a simple workload: FAILED! Signed-off-by: Namhyung Kim <namhyung@kernel.org> Acked-by: Jiri Olsa <jolsa@redhat.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Ian Rogers <irogers@google.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Leo Yan <leo.yan@linaro.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Link: https://lore.kernel.org/r/20210301140409.184570-4-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

The evlist has the maps with its own refcounts so we don't need to set the pointers to NULL. Otherwise following error was reported by Asan. Also change the goto label since it doesn't need to have two. # perf test -v 25 25: Software clock events period values : --- start --- test child forked, pid 149154 mmap size 528384B mmap size 528384B ================================================================= ==149154==ERROR: LeakSanitizer: detected memory leaks Direct leak of 32 byte(s) in 1 object(s) allocated from: #0 0x7fef5cd071f8 in __interceptor_realloc ../../../../src/libsanitizer/asan/asan_malloc_linux.cpp:164 #1 0x56260d5e8b8e in perf_thread_map__realloc /home/namhyung/project/linux/tools/lib/perf/threadmap.c:23 #2 0x56260d3df7a9 in thread_map__new_by_tid util/thread_map.c:63 #3 0x56260d2ac6b2 in __test__sw_clock_freq tests/sw-clock.c:65 #4 0x56260d26d8fb in run_test tests/builtin-test.c:428 #5 0x56260d26d8fb in test_and_print tests/builtin-test.c:458 #6 0x56260d26fa53 in __cmd_test tests/builtin-test.c:679 #7 0x56260d26fa53 in cmd_test tests/builtin-test.c:825 #8 0x56260d2dbb64 in run_builtin /home/namhyung/project/linux/tools/perf/perf.c:313 #9 0x56260d165a88 in handle_internal_command /home/namhyung/project/linux/tools/perf/perf.c:365 #10 0x56260d165a88 in run_argv /home/namhyung/project/linux/tools/perf/perf.c:409 #11 0x56260d165a88 in main /home/namhyung/project/linux/tools/perf/perf.c:539 #12 0x7fef5c83cd09 in __libc_start_main ../csu/libc-start.c:308 ... test child finished with 1 ---- end ---- Software clock events period values : FAILED! Signed-off-by: Namhyung Kim <namhyung@kernel.org> Acked-by: Jiri Olsa <jolsa@redhat.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Ian Rogers <irogers@google.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Leo Yan <leo.yan@linaro.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Link: https://lore.kernel.org/r/20210301140409.184570-5-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

The evlist and the cpu/thread maps should be released together. Otherwise following error was reported by Asan. Note that this test still has memory leaks in DSOs so it still fails even after this change. I'll take a look at that too. # perf test -v 26 26: Object code reading : --- start --- test child forked, pid 154184 Looking at the vmlinux_path (8 entries long) symsrc__init: build id mismatch for vmlinux. symsrc__init: cannot get elf header. Using /proc/kcore for kernel data Using /proc/kallsyms for symbols Parsing event 'cycles' mmap size 528384B ... ================================================================= ==154184==ERROR: LeakSanitizer: detected memory leaks Direct leak of 439 byte(s) in 1 object(s) allocated from: #0 0x7fcb66e77037 in __interceptor_calloc ../../../../src/libsanitizer/asan/asan_malloc_linux.cpp:154 #1 0x55ad9b7e821e in dso__new_id util/dso.c:1256 #2 0x55ad9b8cfd4a in __machine__addnew_vdso util/vdso.c:132 #3 0x55ad9b8cfd4a in machine__findnew_vdso util/vdso.c:347 #4 0x55ad9b845b7e in map__new util/map.c:176 #5 0x55ad9b8415a2 in machine__process_mmap2_event util/machine.c:1787 #6 0x55ad9b8fab16 in perf_tool__process_synth_event util/synthetic-events.c:64 #7 0x55ad9b8fab16 in perf_event__synthesize_mmap_events util/synthetic-events.c:499 #8 0x55ad9b8fbfdf in __event__synthesize_thread util/synthetic-events.c:741 #9 0x55ad9b8ff3e3 in perf_event__synthesize_thread_map util/synthetic-events.c:833 #10 0x55ad9b738585 in do_test_code_reading tests/code-reading.c:608 #11 0x55ad9b73b25d in test__code_reading tests/code-reading.c:722 #12 0x55ad9b6f28fb in run_test tests/builtin-test.c:428 #13 0x55ad9b6f28fb in test_and_print tests/builtin-test.c:458 #14 0x55ad9b6f4a53 in __cmd_test tests/builtin-test.c:679 #15 0x55ad9b6f4a53 in cmd_test tests/builtin-test.c:825 #16 0x55ad9b760cc4 in run_builtin /home/namhyung/project/linux/tools/perf/perf.c:313 #17 0x55ad9b5eaa88 in handle_internal_command /home/namhyung/project/linux/tools/perf/perf.c:365 #18 0x55ad9b5eaa88 in run_argv /home/namhyung/project/linux/tools/perf/perf.c:409 #19 0x55ad9b5eaa88 in main /home/namhyung/project/linux/tools/perf/perf.c:539 #20 0x7fcb669acd09 in __libc_start_main ../csu/libc-start.c:308 ... SUMMARY: AddressSanitizer: 471 byte(s) leaked in 2 allocation(s). test child finished with 1 ---- end ---- Object code reading: FAILED! Signed-off-by: Namhyung Kim <namhyung@kernel.org> Acked-by: Jiri Olsa <jolsa@redhat.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Ian Rogers <irogers@google.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Leo Yan <leo.yan@linaro.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Link: https://lore.kernel.org/r/20210301140409.184570-6-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

The evlist and the cpu/thread maps should be released together. Otherwise following error was reported by Asan. $ perf test -v 28 28: Use a dummy software event to keep tracking: --- start --- test child forked, pid 156810 mmap size 528384B ================================================================= ==156810==ERROR: LeakSanitizer: detected memory leaks Direct leak of 40 byte(s) in 1 object(s) allocated from: #0 0x7f637d2bce8f in __interceptor_malloc ../../../../src/libsanitizer/asan/asan_malloc_linux.cpp:145 #1 0x55cc6295cffa in cpu_map__trim_new /home/namhyung/project/linux/tools/lib/perf/cpumap.c:79 #2 0x55cc6295da1f in perf_cpu_map__read /home/namhyung/project/linux/tools/lib/perf/cpumap.c:149 #3 0x55cc6295e1df in cpu_map__read_all_cpu_map /home/namhyung/project/linux/tools/lib/perf/cpumap.c:166 #4 0x55cc6295e1df in perf_cpu_map__new /home/namhyung/project/linux/tools/lib/perf/cpumap.c:181 #5 0x55cc626287cf in test__keep_tracking tests/keep-tracking.c:84 #6 0x55cc625e38fb in run_test tests/builtin-test.c:428 #7 0x55cc625e38fb in test_and_print tests/builtin-test.c:458 #8 0x55cc625e5a53 in __cmd_test tests/builtin-test.c:679 #9 0x55cc625e5a53 in cmd_test tests/builtin-test.c:825 #10 0x55cc62651cc4 in run_builtin /home/namhyung/project/linux/tools/perf/perf.c:313 #11 0x55cc624dba88 in handle_internal_command /home/namhyung/project/linux/tools/perf/perf.c:365 #12 0x55cc624dba88 in run_argv /home/namhyung/project/linux/tools/perf/perf.c:409 #13 0x55cc624dba88 in main /home/namhyung/project/linux/tools/perf/perf.c:539 #14 0x7f637cdf2d09 in __libc_start_main ../csu/libc-start.c:308 SUMMARY: AddressSanitizer: 72 byte(s) leaked in 2 allocation(s). test child finished with 1 ---- end ---- Use a dummy software event to keep tracking: FAILED! Signed-off-by: Namhyung Kim <namhyung@kernel.org> Acked-by: Jiri Olsa <jolsa@redhat.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Ian Rogers <irogers@google.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Leo Yan <leo.yan@linaro.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Link: https://lore.kernel.org/r/20210301140409.184570-7-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

The evlist and cpu/thread maps should be released together. Otherwise the following error was reported by Asan. $ perf test -v 35 35: Track with sched_switch : --- start --- test child forked, pid 159287 Using CPUID GenuineIntel-6-8E-C mmap size 528384B 1295 events recorded ================================================================= ==159287==ERROR: LeakSanitizer: detected memory leaks Direct leak of 40 byte(s) in 1 object(s) allocated from: #0 0x7fa28d9a2e8f in __interceptor_malloc ../../../../src/libsanitizer/asan/asan_malloc_linux.cpp:145 #1 0x5652f5a5affa in cpu_map__trim_new /home/namhyung/project/linux/tools/lib/perf/cpumap.c:79 #2 0x5652f5a5ba1f in perf_cpu_map__read /home/namhyung/project/linux/tools/lib/perf/cpumap.c:149 #3 0x5652f5a5c1df in cpu_map__read_all_cpu_map /home/namhyung/project/linux/tools/lib/perf/cpumap.c:166 #4 0x5652f5a5c1df in perf_cpu_map__new /home/namhyung/project/linux/tools/lib/perf/cpumap.c:181 #5 0x5652f5723bbf in test__switch_tracking tests/switch-tracking.c:350 #6 0x5652f56e18fb in run_test tests/builtin-test.c:428 #7 0x5652f56e18fb in test_and_print tests/builtin-test.c:458 #8 0x5652f56e3a53 in __cmd_test tests/builtin-test.c:679 #9 0x5652f56e3a53 in cmd_test tests/builtin-test.c:825 #10 0x5652f574fcc4 in run_builtin /home/namhyung/project/linux/tools/perf/perf.c:313 #11 0x5652f55d9a88 in handle_internal_command /home/namhyung/project/linux/tools/perf/perf.c:365 #12 0x5652f55d9a88 in run_argv /home/namhyung/project/linux/tools/perf/perf.c:409 #13 0x5652f55d9a88 in main /home/namhyung/project/linux/tools/perf/perf.c:539 #14 0x7fa28d4d8d09 in __libc_start_main ../csu/libc-start.c:308 SUMMARY: AddressSanitizer: 72 byte(s) leaked in 2 allocation(s). test child finished with 1 ---- end ---- Track with sched_switch: FAILED! Signed-off-by: Namhyung Kim <namhyung@kernel.org> Acked-by: Jiri Olsa <jolsa@redhat.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Ian Rogers <irogers@google.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Leo Yan <leo.yan@linaro.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Link: https://lore.kernel.org/r/20210301140409.184570-8-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

It missed to call perf_thread_map__put() after using the map. $ perf test -v 43 43: Synthesize thread map : --- start --- test child forked, pid 162640 ================================================================= ==162640==ERROR: LeakSanitizer: detected memory leaks Direct leak of 32 byte(s) in 1 object(s) allocated from: #0 0x7fd48cdaa1f8 in __interceptor_realloc ../../../../src/libsanitizer/asan/asan_malloc_linux.cpp:164 #1 0x563e6d5f8d0e in perf_thread_map__realloc /home/namhyung/project/linux/tools/lib/perf/threadmap.c:23 #2 0x563e6d3ef69a in thread_map__new_by_pid util/thread_map.c:46 #3 0x563e6d2cec90 in test__thread_map_synthesize tests/thread-map.c:97 #4 0x563e6d27d8fb in run_test tests/builtin-test.c:428 #5 0x563e6d27d8fb in test_and_print tests/builtin-test.c:458 #6 0x563e6d27fa53 in __cmd_test tests/builtin-test.c:679 #7 0x563e6d27fa53 in cmd_test tests/builtin-test.c:825 #8 0x563e6d2ebce4 in run_builtin /home/namhyung/project/linux/tools/perf/perf.c:313 #9 0x563e6d175a88 in handle_internal_command /home/namhyung/project/linux/tools/perf/perf.c:365 #10 0x563e6d175a88 in run_argv /home/namhyung/project/linux/tools/perf/perf.c:409 #11 0x563e6d175a88 in main /home/namhyung/project/linux/tools/perf/perf.c:539 #12 0x7fd48c8dfd09 in __libc_start_main ../csu/libc-start.c:308 SUMMARY: AddressSanitizer: 8224 byte(s) leaked in 2 allocation(s). test child finished with 1 ---- end ---- Synthesize thread map: FAILED! Signed-off-by: Namhyung Kim <namhyung@kernel.org> Acked-by: Jiri Olsa <jolsa@redhat.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Ian Rogers <irogers@google.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Leo Yan <leo.yan@linaro.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Link: https://lore.kernel.org/r/20210301140409.184570-9-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

It should be released after printing the map. $ perf test -v 52 52: Print cpu map : --- start --- test child forked, pid 172233 ================================================================= ==172233==ERROR: LeakSanitizer: detected memory leaks Direct leak of 156 byte(s) in 1 object(s) allocated from: #0 0x7fc472518e8f in __interceptor_malloc ../../../../src/libsanitizer/asan/asan_malloc_linux.cpp:145 #1 0x55e63b378f7a in cpu_map__trim_new /home/namhyung/project/linux/tools/lib/perf/cpumap.c:79 #2 0x55e63b37a05c in perf_cpu_map__new /home/namhyung/project/linux/tools/lib/perf/cpumap.c:237 #3 0x55e63b056d16 in cpu_map_print tests/cpumap.c:102 #4 0x55e63b056d16 in test__cpu_map_print tests/cpumap.c:120 #5 0x55e63afff8fb in run_test tests/builtin-test.c:428 #6 0x55e63afff8fb in test_and_print tests/builtin-test.c:458 #7 0x55e63b001a53 in __cmd_test tests/builtin-test.c:679 #8 0x55e63b001a53 in cmd_test tests/builtin-test.c:825 #9 0x55e63b06dc44 in run_builtin /home/namhyung/project/linux/tools/perf/perf.c:313 #10 0x55e63aef7a88 in handle_internal_command /home/namhyung/project/linux/tools/perf/perf.c:365 #11 0x55e63aef7a88 in run_argv /home/namhyung/project/linux/tools/perf/perf.c:409 #12 0x55e63aef7a88 in main /home/namhyung/project/linux/tools/perf/perf.c:539 #13 0x7fc47204ed09 in __libc_start_main ../csu/libc-start.c:308 ... SUMMARY: AddressSanitizer: 448 byte(s) leaked in 7 allocation(s). test child finished with 1 ---- end ---- Print cpu map: FAILED! Signed-off-by: Namhyung Kim <namhyung@kernel.org> Acked-by: Jiri Olsa <jolsa@redhat.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Ian Rogers <irogers@google.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Leo Yan <leo.yan@linaro.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Link: https://lore.kernel.org/r/20210301140409.184570-11-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

It should release the maps at the end. $ perf test -v 71 71: Convert perf time to TSC : --- start --- test child forked, pid 178744 mmap size 528384B 1st event perf time 59207256505278 tsc 13187166645142 rdtsc time 59207256542151 tsc 13187166723020 2nd event perf time 59207256543749 tsc 13187166726393 ================================================================= ==178744==ERROR: LeakSanitizer: detected memory leaks Direct leak of 40 byte(s) in 1 object(s) allocated from: #0 0x7faf601f9e8f in __interceptor_malloc ../../../../src/libsanitizer/asan/asan_malloc_linux.cpp:145 #1 0x55b620cfc00a in cpu_map__trim_new /home/namhyung/project/linux/tools/lib/perf/cpumap.c:79 #2 0x55b620cfca2f in perf_cpu_map__read /home/namhyung/project/linux/tools/lib/perf/cpumap.c:149 #3 0x55b620cfd1ef in cpu_map__read_all_cpu_map /home/namhyung/project/linux/tools/lib/perf/cpumap.c:166 #4 0x55b620cfd1ef in perf_cpu_map__new /home/namhyung/project/linux/tools/lib/perf/cpumap.c:181 #5 0x55b6209ef1b2 in test__perf_time_to_tsc tests/perf-time-to-tsc.c:73 #6 0x55b6209828fb in run_test tests/builtin-test.c:428 #7 0x55b6209828fb in test_and_print tests/builtin-test.c:458 #8 0x55b620984a53 in __cmd_test tests/builtin-test.c:679 #9 0x55b620984a53 in cmd_test tests/builtin-test.c:825 #10 0x55b6209f0cd4 in run_builtin /home/namhyung/project/linux/tools/perf/perf.c:313 #11 0x55b62087aa88 in handle_internal_command /home/namhyung/project/linux/tools/perf/perf.c:365 #12 0x55b62087aa88 in run_argv /home/namhyung/project/linux/tools/perf/perf.c:409 #13 0x55b62087aa88 in main /home/namhyung/project/linux/tools/perf/perf.c:539 #14 0x7faf5fd2fd09 in __libc_start_main ../csu/libc-start.c:308 SUMMARY: AddressSanitizer: 72 byte(s) leaked in 2 allocation(s). test child finished with 1 ---- end ---- Convert perf time to TSC: FAILED! Signed-off-by: Namhyung Kim <namhyung@kernel.org> Acked-by: Jiri Olsa <jolsa@redhat.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Ian Rogers <irogers@google.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Leo Yan <leo.yan@linaro.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Link: https://lore.kernel.org/r/20210301140409.184570-12-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

I got a segfault when using -r option with event groups. The option makes it run the workload multiple times and it will reuse the evlist and evsel for each run. While most of resources are allocated and freed properly, the id hash in the evlist was not and it resulted in the bug. You can see it with the address sanitizer like below: $ perf stat -r 100 -e '{cycles,instructions}' true ================================================================= ==693052==ERROR: AddressSanitizer: heap-use-after-free on address 0x6080000003d0 at pc 0x558c57732835 bp 0x7fff1526adb0 sp 0x7fff1526ada8 WRITE of size 8 at 0x6080000003d0 thread T0 #0 0x558c57732834 in hlist_add_head /home/namhyung/project/linux/tools/include/linux/list.h:644 #1 0x558c57732834 in perf_evlist__id_hash /home/namhyung/project/linux/tools/lib/perf/evlist.c:237 #2 0x558c57732834 in perf_evlist__id_add /home/namhyung/project/linux/tools/lib/perf/evlist.c:244 #3 0x558c57732834 in perf_evlist__id_add_fd /home/namhyung/project/linux/tools/lib/perf/evlist.c:285 #4 0x558c5747733e in store_evsel_ids util/evsel.c:2765 #5 0x558c5747733e in evsel__store_ids util/evsel.c:2782 #6 0x558c5730b717 in __run_perf_stat /home/namhyung/project/linux/tools/perf/builtin-stat.c:895 #7 0x558c5730b717 in run_perf_stat /home/namhyung/project/linux/tools/perf/builtin-stat.c:1014 #8 0x558c5730b717 in cmd_stat /home/namhyung/project/linux/tools/perf/builtin-stat.c:2446 #9 0x558c57427c24 in run_builtin /home/namhyung/project/linux/tools/perf/perf.c:313 #10 0x558c572b1a48 in handle_internal_command /home/namhyung/project/linux/tools/perf/perf.c:365 #11 0x558c572b1a48 in run_argv /home/namhyung/project/linux/tools/perf/perf.c:409 #12 0x558c572b1a48 in main /home/namhyung/project/linux/tools/perf/perf.c:539 #13 0x7fcadb9f7d09 in __libc_start_main ../csu/libc-start.c:308 #14 0x558c572b60f9 in _start (/home/namhyung/project/linux/tools/perf/perf+0x45d0f9) Actually the nodes in the hash table are struct perf_stream_id and they were freed in the previous run. Fix it by resetting the hash. Signed-off-by: Namhyung Kim <namhyung@kernel.org> Acked-by: Jiri Olsa <jolsa@redhat.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Ian Rogers <irogers@google.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Link: https://lore.kernel.org/r/20210225035148.778569-2-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

I got several memory leak reports from Asan with a simple command. It was because VDSO is not released due to the refcount. Like in __dsos_addnew_id(), it should put the refcount after adding to the list. $ perf record true [ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 0.030 MB perf.data (10 samples) ] ================================================================= ==692599==ERROR: LeakSanitizer: detected memory leaks Direct leak of 439 byte(s) in 1 object(s) allocated from: #0 0x7fea52341037 in __interceptor_calloc ../../../../src/libsanitizer/asan/asan_malloc_linux.cpp:154 #1 0x559bce4aa8ee in dso__new_id util/dso.c:1256 #2 0x559bce59245a in __machine__addnew_vdso util/vdso.c:132 #3 0x559bce59245a in machine__findnew_vdso util/vdso.c:347 #4 0x559bce50826c in map__new util/map.c:175 #5 0x559bce503c92 in machine__process_mmap2_event util/machine.c:1787 #6 0x559bce512f6b in machines__deliver_event util/session.c:1481 #7 0x559bce515107 in perf_session__deliver_event util/session.c:1551 #8 0x559bce51d4d2 in do_flush util/ordered-events.c:244 #9 0x559bce51d4d2 in __ordered_events__flush util/ordered-events.c:323 #10 0x559bce519bea in __perf_session__process_events util/session.c:2268 #11 0x559bce519bea in perf_session__process_events util/session.c:2297 #12 0x559bce2e7a52 in process_buildids /home/namhyung/project/linux/tools/perf/builtin-record.c:1017 #13 0x559bce2e7a52 in record__finish_output /home/namhyung/project/linux/tools/perf/builtin-record.c:1234 #14 0x559bce2ed4f6 in __cmd_record /home/namhyung/project/linux/tools/perf/builtin-record.c:2026 #15 0x559bce2ed4f6 in cmd_record /home/namhyung/project/linux/tools/perf/builtin-record.c:2858 #16 0x559bce422db4 in run_builtin /home/namhyung/project/linux/tools/perf/perf.c:313 #17 0x559bce2acac8 in handle_internal_command /home/namhyung/project/linux/tools/perf/perf.c:365 #18 0x559bce2acac8 in run_argv /home/namhyung/project/linux/tools/perf/perf.c:409 #19 0x559bce2acac8 in main /home/namhyung/project/linux/tools/perf/perf.c:539 #20 0x7fea51e76d09 in __libc_start_main ../csu/libc-start.c:308 Indirect leak of 32 byte(s) in 1 object(s) allocated from: #0 0x7fea52341037 in __interceptor_calloc ../../../../src/libsanitizer/asan/asan_malloc_linux.cpp:154 #1 0x559bce520907 in nsinfo__copy util/namespaces.c:169 #2 0x559bce50821b in map__new util/map.c:168 #3 0x559bce503c92 in machine__process_mmap2_event util/machine.c:1787 #4 0x559bce512f6b in machines__deliver_event util/session.c:1481 #5 0x559bce515107 in perf_session__deliver_event util/session.c:1551 #6 0x559bce51d4d2 in do_flush util/ordered-events.c:244 #7 0x559bce51d4d2 in __ordered_events__flush util/ordered-events.c:323 #8 0x559bce519bea in __perf_session__process_events util/session.c:2268 #9 0x559bce519bea in perf_session__process_events util/session.c:2297 #10 0x559bce2e7a52 in process_buildids /home/namhyung/project/linux/tools/perf/builtin-record.c:1017 #11 0x559bce2e7a52 in record__finish_output /home/namhyung/project/linux/tools/perf/builtin-record.c:1234 #12 0x559bce2ed4f6 in __cmd_record /home/namhyung/project/linux/tools/perf/builtin-record.c:2026 #13 0x559bce2ed4f6 in cmd_record /home/namhyung/project/linux/tools/perf/builtin-record.c:2858 #14 0x559bce422db4 in run_builtin /home/namhyung/project/linux/tools/perf/perf.c:313 #15 0x559bce2acac8 in handle_internal_command /home/namhyung/project/linux/tools/perf/perf.c:365 #16 0x559bce2acac8 in run_argv /home/namhyung/project/linux/tools/perf/perf.c:409 #17 0x559bce2acac8 in main /home/namhyung/project/linux/tools/perf/perf.c:539 #18 0x7fea51e76d09 in __libc_start_main ../csu/libc-start.c:308 SUMMARY: AddressSanitizer: 471 byte(s) leaked in 2 allocation(s). Signed-off-by: Namhyung Kim <namhyung@kernel.org> Acked-by: Jiri Olsa <jolsa@redhat.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Ian Rogers <irogers@google.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lore.kernel.org/lkml/20210315045641.700430-1-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

The following deadlock is detected: truncate -> setattr path is waiting for pending direct IO to be done (inode->i_dio_count become zero) with inode->i_rwsem held (down_write). PID: 14827 TASK: ffff881686a9af80 CPU: 20 COMMAND: "ora_p005_hrltd9" #0 __schedule at ffffffff818667cc #1 schedule at ffffffff81866de6 #2 inode_dio_wait at ffffffff812a2d04 #3 ocfs2_setattr at ffffffffc05f322e [ocfs2] #4 notify_change at ffffffff812a5a09 #5 do_truncate at ffffffff812808f5 #6 do_sys_ftruncate.constprop.18 at ffffffff81280cf2 #7 sys_ftruncate at ffffffff81280d8e #8 do_syscall_64 at ffffffff81003949 #9 entry_SYSCALL_64_after_hwframe at ffffffff81a001ad dio completion path is going to complete one direct IO (decrement inode->i_dio_count), but before that it hung at locking inode->i_rwsem: #0 __schedule+700 at ffffffff818667cc #1 schedule+54 at ffffffff81866de6 #2 rwsem_down_write_failed+536 at ffffffff8186aa28 #3 call_rwsem_down_write_failed+23 at ffffffff8185a1b7 #4 down_write+45 at ffffffff81869c9d #5 ocfs2_dio_end_io_write+180 at ffffffffc05d5444 [ocfs2] #6 ocfs2_dio_end_io+85 at ffffffffc05d5a85 [ocfs2] #7 dio_complete+140 at ffffffff812c873c #8 dio_aio_complete_work+25 at ffffffff812c89f9 #9 process_one_work+361 at ffffffff810b1889 #10 worker_thread+77 at ffffffff810b233d #11 kthread+261 at ffffffff810b7fd5 #12 ret_from_fork+62 at ffffffff81a0035e Thus above forms ABBA deadlock. The same deadlock was mentioned in upstream commit 28f5a8a ("ocfs2: should wait dio before inode lock in ocfs2_setattr()"). It seems that that commit only removed the cluster lock (the victim of above dead lock) from the ABBA deadlock party. End-user visible effects: Process hang in truncate -> ocfs2_setattr path and other processes hang at ocfs2_dio_end_io_write path. This is to fix the deadlock itself. It removes inode_lock() call from dio completion path to remove the deadlock and add ip_alloc_sem lock in setattr path to synchronize the inode modifications. [wen.gang.wang@oracle.com: remove the "had_alloc_lock" as suggested] Link: https://lkml.kernel.org/r/20210402171344.1605-1-wen.gang.wang@oracle.com Link: https://lkml.kernel.org/r/20210331203654.3911-1-wen.gang.wang@oracle.com Signed-off-by: Wengang Wang <wen.gang.wang@oracle.com> Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com> Cc: Mark Fasheh <mark@fasheh.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Junxiao Bi <junxiao.bi@oracle.com> Cc: Changwei Ge <gechangwei@live.cn> Cc: Gang He <ghe@suse.com> Cc: Jun Piao <piaojun@huawei.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

…nect It's possible to trigger NULL pointer dereference by local unprivileged user, when calling getsockname() after failed bind() (e.g. the bind fails because LLCP_SAP_MAX used as SAP): BUG: kernel NULL pointer dereference, address: 0000000000000000 CPU: 1 PID: 426 Comm: llcp_sock_getna Not tainted 5.13.0-rc2-next-20210521+ #9 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-1 04/01/2014 Call Trace: llcp_sock_getname+0xb1/0xe0 __sys_getpeername+0x95/0xc0 ? lockdep_hardirqs_on_prepare+0xd5/0x180 ? syscall_enter_from_user_mode+0x1c/0x40 __x64_sys_getpeername+0x11/0x20 do_syscall_64+0x36/0x70 entry_SYSCALL_64_after_hwframe+0x44/0xae This can be reproduced with Syzkaller C repro (bind followed by getpeername): https://syzkaller.appspot.com/x/repro.c?x=14def446e00000 Cc: <stable@vger.kernel.org> Fixes: d646960 ("NFC: Initial LLCP support") Reported-by: syzbot+80fb126e7f7d8b1a5914@syzkaller.appspotmail.com Reported-by: butt3rflyh4ck <butterflyhuangxx@gmail.com> Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com> Link: https://lore.kernel.org/r/20210531072138.5219-1-krzysztof.kozlowski@canonical.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>

ASan reported a memory leak caused by info_linear not being deallocated. The info_linear was allocated during in perf_event__synthesize_one_bpf_prog(). This patch adds the corresponding free() when bpf_prog_info_node is freed in perf_env__purge_bpf(). $ sudo ./perf record -- sleep 5 [ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 0.025 MB perf.data (8 samples) ] ================================================================= ==297735==ERROR: LeakSanitizer: detected memory leaks Direct leak of 7688 byte(s) in 19 object(s) allocated from: #0 0x4f420f in malloc (/home/user/linux/tools/perf/perf+0x4f420f) #1 0xc06a74 in bpf_program__get_prog_info_linear /home/user/linux/tools/lib/bpf/libbpf.c:11113:16 #2 0xb426fe in perf_event__synthesize_one_bpf_prog /home/user/linux/tools/perf/util/bpf-event.c:191:16 #3 0xb42008 in perf_event__synthesize_bpf_events /home/user/linux/tools/perf/util/bpf-event.c:410:9 #4 0x594596 in record__synthesize /home/user/linux/tools/perf/builtin-record.c:1490:8 #5 0x58c9ac in __cmd_record /home/user/linux/tools/perf/builtin-record.c:1798:8 #6 0x58990b in cmd_record /home/user/linux/tools/perf/builtin-record.c:2901:8 #7 0x7b2a20 in run_builtin /home/user/linux/tools/perf/perf.c:313:11 #8 0x7b12ff in handle_internal_command /home/user/linux/tools/perf/perf.c:365:8 #9 0x7b2583 in run_argv /home/user/linux/tools/perf/perf.c:409:2 #10 0x7b0d79 in main /home/user/linux/tools/perf/perf.c:539:3 #11 0x7fa357ef6b74 in __libc_start_main /usr/src/debug/glibc-2.33-8.fc34.x86_64/csu/../csu/libc-start.c:332:16 Signed-off-by: Riccardo Mancini <rickyman7@gmail.com> Acked-by: Ian Rogers <irogers@google.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Andrii Nakryiko <andrii@kernel.org> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: Jiri Olsa <jolsa@redhat.com> Cc: John Fastabend <john.fastabend@gmail.com> Cc: KP Singh <kpsingh@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Martin KaFai Lau <kafai@fb.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Song Liu <songliubraving@fb.com> Cc: Yonghong Song <yhs@fb.com> Link: http://lore.kernel.org/lkml/20210602224024.300485-1-rickyman7@gmail.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Enabling the framebuffer leads to a system hang. Running, as a debug hack, the store_pan() function in drivers/video/fbdev/core/fbsysfs.c without taking the console_lock, allows to see the crash backtrace on the serial line. ~ # echo 0 0 > /sys/class/graphics/fb0/pan [ 9.719414] Unhandled exception: IPSR = 00000005 LR = fffffff1 [ 9.726937] CPU: 0 PID: 49 Comm: sh Not tainted 5.13.0-rc5 #9 [ 9.733008] Hardware name: STM32 (Device Tree Support) [ 9.738296] PC is at clk_gate_is_enabled+0x0/0x28 [ 9.743426] LR is at stm32f4_pll_div_set_rate+0xf/0x38 [ 9.748857] pc : [<0011e4be>] lr : [<0011f9e3>] psr: 0100000b [ 9.755373] sp : 00bc7be0 ip : 00000000 fp : 001f3ac4 [ 9.760812] r10: 002610d0 r9 : 01efe920 r8 : 00540560 [ 9.766269] r7 : 02e7ddb0 r6 : 0173eed8 r5 : 00000000 r4 : 004027c0 [ 9.773081] r3 : 0011e4bf r2 : 02e7ddb0 r1 : 0173eed8 r0 : 1d3267b8 [ 9.779911] xPSR: 0100000b [ 9.782719] CPU: 0 PID: 49 Comm: sh Not tainted 5.13.0-rc5 #9 [ 9.788791] Hardware name: STM32 (Device Tree Support) [ 9.794120] [<0000afa1>] (unwind_backtrace) from [<0000a33f>] (show_stack+0xb/0xc) [ 9.802421] [<0000a33f>] (show_stack) from [<0000a8df>] (__invalid_entry+0x4b/0x4c) The `pll_num' field in the post_div_data configuration contained a wrong value which also referenced an uninitialized hardware clock when clk_register_pll_div() was called. Fixes: 517633e ("clk: stm32f4: Add post divisor for I2S & SAI PLLs") Signed-off-by: Dario Binacchi <dariobin@libero.it> Reviewed-by: Gabriel Fernandez <gabriel.fernandez@st.com> Link: https://lore.kernel.org/r/20210725160725.10788-1-dariobin@libero.it Signed-off-by: Stephen Boyd <sboyd@kernel.org>

When bringing down the netdevice or system shutdown, a panic can be triggered while accessing the sysfs path because the device is already removed. [ 755.549084] mlx5_core 0000:12:00.1: Shutdown was called [ 756.404455] mlx5_core 0000:12:00.0: Shutdown was called ... [ 757.937260] BUG: unable to handle kernel NULL pointer dereference at (null) [ 758.031397] IP: [<ffffffff8ee11acb>] dma_pool_alloc+0x1ab/0x280 crash> bt ... PID: 12649 TASK: ffff8924108f2100 CPU: 1 COMMAND: "amsd" ... #9 [ffff89240e1a38b0] page_fault at ffffffff8f38c778 [exception RIP: dma_pool_alloc+0x1ab] RIP: ffffffff8ee11acb RSP: ffff89240e1a3968 RFLAGS: 00010046 RAX: 0000000000000246 RBX: ffff89243d874100 RCX: 0000000000001000 RDX: 0000000000000000 RSI: 0000000000000246 RDI: ffff89243d874090 RBP: ffff89240e1a39c0 R8: 000000000001f080 R9: ffff8905ffc03c00 R10: ffffffffc04680d4 R11: ffffffff8edde9fd R12: 00000000000080d0 R13: ffff89243d874090 R14: ffff89243d874080 R15: 0000000000000000 ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0018 #10 [ffff89240e1a39c8] mlx5_alloc_cmd_msg at ffffffffc04680f3 [mlx5_core] #11 [ffff89240e1a3a18] cmd_exec at ffffffffc046ad62 [mlx5_core] #12 [ffff89240e1a3ab8] mlx5_cmd_exec at ffffffffc046b4fb [mlx5_core] #13 [ffff89240e1a3ae8] mlx5_core_access_reg at ffffffffc0475434 [mlx5_core] #14 [ffff89240e1a3b40] mlx5e_get_fec_caps at ffffffffc04a7348 [mlx5_core] #15 [ffff89240e1a3bb0] get_fec_supported_advertised at ffffffffc04992bf [mlx5_core] #16 [ffff89240e1a3c08] mlx5e_get_link_ksettings at ffffffffc049ab36 [mlx5_core] #17 [ffff89240e1a3ce8] __ethtool_get_link_ksettings at ffffffff8f25db46 #18 [ffff89240e1a3d48] speed_show at ffffffff8f277208 #19 [ffff89240e1a3dd8] dev_attr_show at ffffffff8f0b70e3 #20 [ffff89240e1a3df8] sysfs_kf_seq_show at ffffffff8eedbedf #21 [ffff89240e1a3e18] kernfs_seq_show at ffffffff8eeda596 #22 [ffff89240e1a3e28] seq_read at ffffffff8ee76d10 #23 [ffff89240e1a3e98] kernfs_fop_read at ffffffff8eedaef5 #24 [ffff89240e1a3ed8] vfs_read at ffffffff8ee4e3ff #25 [ffff89240e1a3f08] sys_read at ffffffff8ee4f27f #26 [ffff89240e1a3f50] system_call_fastpath at ffffffff8f395f92 crash> net_device.state ffff89443b0c0000 state = 0x5 (__LINK_STATE_START| __LINK_STATE_NOCARRIER) To prevent this scenario, we also make sure that the netdevice is present. Signed-off-by: suresh kumar <suresh2514@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>

While handling PCI errors (AER flow) driver tries to disable NAPI [napi_disable()] after NAPI is deleted [__netif_napi_del()] which causes unexpected system hang/crash. System message log shows the following: ======================================= [ 3222.537510] EEH: Detected PCI bus error on PHB#384-PE#800000 [ 3222.537511] EEH: This PCI device has failed 2 times in the last hour and will be permanently disabled after 5 failures. [ 3222.537512] EEH: Notify device drivers to shutdown [ 3222.537513] EEH: Beginning: 'error_detected(IO frozen)' [ 3222.537514] EEH: PE#800000 (PCI 0384:80:00.0): Invoking bnx2x->error_detected(IO frozen) [ 3222.537516] bnx2x: [bnx2x_io_error_detected:14236(eth14)]IO error detected [ 3222.537650] EEH: PE#800000 (PCI 0384:80:00.0): bnx2x driver reports: 'need reset' [ 3222.537651] EEH: PE#800000 (PCI 0384:80:00.1): Invoking bnx2x->error_detected(IO frozen) [ 3222.537651] bnx2x: [bnx2x_io_error_detected:14236(eth13)]IO error detected [ 3222.537729] EEH: PE#800000 (PCI 0384:80:00.1): bnx2x driver reports: 'need reset' [ 3222.537729] EEH: Finished:'error_detected(IO frozen)' with aggregate recovery state:'need reset' [ 3222.537890] EEH: Collect temporary log [ 3222.583481] EEH: of node=0384:80:00.0 [ 3222.583519] EEH: PCI device/vendor: 168e14e4 [ 3222.583557] EEH: PCI cmd/status register: 00100140 [ 3222.583557] EEH: PCI-E capabilities and status follow: [ 3222.583744] EEH: PCI-E 00: 00020010 012c8da2 00095d5e 00455c82 [ 3222.583892] EEH: PCI-E 10: 10820000 00000000 00000000 00000000 [ 3222.583893] EEH: PCI-E 20: 00000000 [ 3222.583893] EEH: PCI-E AER capability register set follows: [ 3222.584079] EEH: PCI-E AER 00: 13c10001 00000000 00000000 00062030 [ 3222.584230] EEH: PCI-E AER 10: 00002000 000031c0 000001e0 00000000 [ 3222.584378] EEH: PCI-E AER 20: 00000000 00000000 00000000 00000000 [ 3222.584416] EEH: PCI-E AER 30: 00000000 00000000 [ 3222.584416] EEH: of node=0384:80:00.1 [ 3222.584454] EEH: PCI device/vendor: 168e14e4 [ 3222.584491] EEH: PCI cmd/status register: 00100140 [ 3222.584492] EEH: PCI-E capabilities and status follow: [ 3222.584677] EEH: PCI-E 00: 00020010 012c8da2 00095d5e 00455c82 [ 3222.584825] EEH: PCI-E 10: 10820000 00000000 00000000 00000000 [ 3222.584826] EEH: PCI-E 20: 00000000 [ 3222.584826] EEH: PCI-E AER capability register set follows: [ 3222.585011] EEH: PCI-E AER 00: 13c10001 00000000 00000000 00062030 [ 3222.585160] EEH: PCI-E AER 10: 00002000 000031c0 000001e0 00000000 [ 3222.585309] EEH: PCI-E AER 20: 00000000 00000000 00000000 00000000 [ 3222.585347] EEH: PCI-E AER 30: 00000000 00000000 [ 3222.586872] RTAS: event: 5, Type: Platform Error (224), Severity: 2 [ 3222.586873] EEH: Reset without hotplug activity [ 3224.762767] EEH: Beginning: 'slot_reset' [ 3224.762770] EEH: PE#800000 (PCI 0384:80:00.0): Invoking bnx2x->slot_reset() [ 3224.762771] bnx2x: [bnx2x_io_slot_reset:14271(eth14)]IO slot reset initializing... [ 3224.762887] bnx2x 0384:80:00.0: enabling device (0140 -> 0142) [ 3224.768157] bnx2x: [bnx2x_io_slot_reset:14287(eth14)]IO slot reset --> driver unload Uninterruptible tasks ===================== crash> ps | grep UN 213 2 11 c000000004c89e00 UN 0.0 0 0 [eehd] 215 2 0 c000000004c80000 UN 0.0 0 0 [kworker/0:2] 2196 1 28 c000000004504f00 UN 0.1 15936 11136 wickedd 4287 1 9 c00000020d076800 UN 0.0 4032 3008 agetty 4289 1 20 c00000020d056680 UN 0.0 7232 3840 agetty 32423 2 26 c00000020038c580 UN 0.0 0 0 [kworker/26:3] 32871 4241 27 c0000002609ddd00 UN 0.1 18624 11648 sshd 32920 10130 16 c00000027284a100 UN 0.1 48512 12608 sendmail 33092 32987 0 c000000205218b00 UN 0.1 48512 12608 sendmail 33154 4567 16 c000000260e51780 UN 0.1 48832 12864 pickup 33209 4241 36 c000000270cb6500 UN 0.1 18624 11712 sshd 33473 33283 0 c000000205211480 UN 0.1 48512 12672 sendmail 33531 4241 37 c00000023c902780 UN 0.1 18624 11648 sshd EEH handler hung while bnx2x sleeping and holding RTNL lock =========================================================== crash> bt 213 PID: 213 TASK: c000000004c89e00 CPU: 11 COMMAND: "eehd" #0 [c000000004d477e0] __schedule at c000000000c70808 #1 [c000000004d478b0] schedule at c000000000c70ee0 #2 [c000000004d478e0] schedule_timeout at c000000000c76dec #3 [c000000004d479c0] msleep at c0000000002120cc #4 [c000000004d479f0] napi_disable at c000000000a06448 ^^^^^^^^^^^^^^^^ #5 [c000000004d47a30] bnx2x_netif_stop at c0080000018dba94 [bnx2x] #6 [c000000004d47a60] bnx2x_io_slot_reset at c0080000018a551c [bnx2x] #7 [c000000004d47b20] eeh_report_reset at c00000000004c9bc #8 [c000000004d47b90] eeh_pe_report at c00000000004d1a8 #9 [c000000004d47c40] eeh_handle_normal_event at c00000000004da64 And the sleeping source code ============================ crash> dis -ls c000000000a06448 FILE: ../net/core/dev.c LINE: 6702 6697 { 6698 might_sleep(); 6699 set_bit(NAPI_STATE_DISABLE, &n->state); 6700 6701 while (test_and_set_bit(NAPI_STATE_SCHED, &n->state)) * 6702 msleep(1); 6703 while (test_and_set_bit(NAPI_STATE_NPSVC, &n->state)) 6704 msleep(1); 6705 6706 hrtimer_cancel(&n->timer); 6707 6708 clear_bit(NAPI_STATE_DISABLE, &n->state); 6709 } EEH calls into bnx2x twice based on the system log above, first through bnx2x_io_error_detected() and then bnx2x_io_slot_reset(), and executes the following call chains: bnx2x_io_error_detected() +-> bnx2x_eeh_nic_unload() +-> bnx2x_del_all_napi() +-> __netif_napi_del() bnx2x_io_slot_reset() +-> bnx2x_netif_stop() +-> bnx2x_napi_disable() +->napi_disable() Fix this by correcting the sequence of NAPI APIs usage, that is delete the NAPI after disabling it. Fixes: 7fa6f34 ("bnx2x: AER revised") Reported-by: David Christensen <drc@linux.vnet.ibm.com> Tested-by: David Christensen <drc@linux.vnet.ibm.com> Signed-off-by: Manish Chopra <manishc@marvell.com> Signed-off-by: Ariel Elior <aelior@marvell.com> Link: https://lore.kernel.org/r/20220426153913.6966-1-manishc@marvell.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>

This fixes the following error caused by a race condition between phydev->adjust_link() and a MDIO transaction in the phy interrupt handler. The issue was reproduced with the ethernet FEC driver and a micrel KSZ9031 phy. [ 146.195696] fec 2188000.ethernet eth0: MDIO read timeout [ 146.201779] ------------[ cut here ]------------ [ 146.206671] WARNING: CPU: 0 PID: 571 at drivers/net/phy/phy.c:942 phy_error+0x24/0x6c [ 146.214744] Modules linked in: bnep imx_vdoa imx_sdma evbug [ 146.220640] CPU: 0 PID: 571 Comm: irq/128-2188000 Not tainted 5.18.0-rc3-00080-gd569e86915b7 #9 [ 146.229563] Hardware name: Freescale i.MX6 Quad/DualLite (Device Tree) [ 146.236257] unwind_backtrace from show_stack+0x10/0x14 [ 146.241640] show_stack from dump_stack_lvl+0x58/0x70 [ 146.246841] dump_stack_lvl from __warn+0xb4/0x24c [ 146.251772] __warn from warn_slowpath_fmt+0x5c/0xd4 [ 146.256873] warn_slowpath_fmt from phy_error+0x24/0x6c [ 146.262249] phy_error from kszphy_handle_interrupt+0x40/0x48 [ 146.268159] kszphy_handle_interrupt from irq_thread_fn+0x1c/0x78 [ 146.274417] irq_thread_fn from irq_thread+0xf0/0x1dc [ 146.279605] irq_thread from kthread+0xe4/0x104 [ 146.284267] kthread from ret_from_fork+0x14/0x28 [ 146.289164] Exception stack(0xe6fa1fb0 to 0xe6fa1ff8) [ 146.294448] 1fa0: 00000000 00000000 00000000 00000000 [ 146.302842] 1fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 [ 146.311281] 1fe0: 00000000 00000000 00000000 00000000 00000013 00000000 [ 146.318262] irq event stamp: 12325 [ 146.321780] hardirqs last enabled at (12333): [<c01984c4>] __up_console_sem+0x50/0x60 [ 146.330013] hardirqs last disabled at (12342): [<c01984b0>] __up_console_sem+0x3c/0x60 [ 146.338259] softirqs last enabled at (12324): [<c01017f0>] __do_softirq+0x2c0/0x624 [ 146.346311] softirqs last disabled at (12319): [<c01300ac>] __irq_exit_rcu+0x138/0x178 [ 146.354447] ---[ end trace 0000000000000000 ]--- With the FEC driver phydev->adjust_link() calls fec_enet_adjust_link() calls fec_stop()/fec_restart() and both these function reset and temporary disable the FEC disrupting any MII transaction that could be happening at the same time. fec_enet_adjust_link() and phy_read() can be running at the same time when we have one additional interrupt before the phy_state_machine() is able to terminate. Thread 1 (phylib WQ) | Thread 2 (phy interrupt) | | phy_interrupt() <-- PHY IRQ | handle_interrupt() | phy_read() | phy_trigger_machine() | --> schedule phylib WQ | | phy_state_machine() | phy_check_link_status() | phy_link_change() | phydev->adjust_link() | fec_enet_adjust_link() | --> FEC reset | phy_interrupt() <-- PHY IRQ | phy_read() | Fix this by acquiring the phydev lock in phy_interrupt(). Link: https://lore.kernel.org/all/20220422152612.GA510015@francesco-nb.int.toradex.com/ Fixes: c974bdb ("net: phy: Use threaded IRQ, to allow IRQ from sleeping devices") cc: <stable@vger.kernel.org> Signed-off-by: Francesco Dolcini <francesco.dolcini@toradex.com> Reviewed-by: Andrew Lunn <andrew@lunn.ch> Link: https://lore.kernel.org/r/20220506060815.327382-1-francesco.dolcini@toradex.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Do not allow to write timestamps on RX rings if PF is being configured. When PF is being configured RX rings can be freed or rebuilt. If at the same time timestamps are updated, the kernel will crash by dereferencing null RX ring pointer. PID: 1449 TASK: ff187d28ed658040 CPU: 34 COMMAND: "ice-ptp-0000:51" #0 [ff1966a94a713bb0] machine_kexec at ffffffff9d05a0be #1 [ff1966a94a713c08] __crash_kexec at ffffffff9d192e9d #2 [ff1966a94a713cd0] crash_kexec at ffffffff9d1941bd #3 [ff1966a94a713ce8] oops_end at ffffffff9d01bd54 #4 [ff1966a94a713d08] no_context at ffffffff9d06bda4 #5 [ff1966a94a713d60] __bad_area_nosemaphore at ffffffff9d06c10c #6 [ff1966a94a713da8] do_page_fault at ffffffff9d06cae4 #7 [ff1966a94a713de0] page_fault at ffffffff9da0107e [exception RIP: ice_ptp_update_cached_phctime+91] RIP: ffffffffc076db8b RSP: ff1966a94a713e98 RFLAGS: 00010246 RAX: 16e3db9c6b7ccae4 RBX: ff187d269dd3c180 RCX: ff187d269cd4d018 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ff187d269cfcc644 R8: ff187d339b9641b0 R9: 0000000000000000 R10: 0000000000000002 R11: 0000000000000000 R12: ff187d269cfcc648 R13: ffffffff9f128784 R14: ffffffff9d101b70 R15: ff187d269cfcc640 ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0018 #8 [ff1966a94a713ea0] ice_ptp_periodic_work at ffffffffc076dbef [ice] #9 [ff1966a94a713ee0] kthread_worker_fn at ffffffff9d101c1b #10 [ff1966a94a713f10] kthread at ffffffff9d101b4d #11 [ff1966a94a713f50] ret_from_fork at ffffffff9da0023f Fixes: 77a7811 ("ice: enable receive hardware timestamping") Signed-off-by: Arkadiusz Kubalewski <arkadiusz.kubalewski@intel.com> Reviewed-by: Michal Schmidt <mschmidt@redhat.com> Tested-by: Dave Cain <dcain@redhat.com> Tested-by: Gurucharan <gurucharanx.g@intel.com> (A Contingent worker at Intel) Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>

This was missed in c3ed222 ("NFSv4: Fix free of uninitialized nfs4_label on referral lookup.") and causes a panic when mounting with '-o trunkdiscovery': PID: 1604 TASK: ffff93dac3520000 CPU: 3 COMMAND: "mount.nfs" #0 [ffffb79140f738f8] machine_kexec at ffffffffaec64bee #1 [ffffb79140f73950] __crash_kexec at ffffffffaeda67fd #2 [ffffb79140f73a18] crash_kexec at ffffffffaeda76ed #3 [ffffb79140f73a30] oops_end at ffffffffaec2658d #4 [ffffb79140f73a50] general_protection at ffffffffaf60111e [exception RIP: nfs_fattr_init+0x5] RIP: ffffffffc0c18265 RSP: ffffb79140f73b08 RFLAGS: 00010246 RAX: 0000000000000000 RBX: ffff93dac304a800 RCX: 0000000000000000 RDX: ffffb79140f73bb0 RSI: ffff93dadc8cbb40 RDI: d03ee11cfaf6bd50 RBP: ffffb79140f73be8 R8: ffffffffc0691560 R9: 0000000000000006 R10: ffff93db3ffd3df8 R11: 0000000000000000 R12: ffff93dac4040000 R13: ffff93dac2848e00 R14: ffffb79140f73b60 R15: ffffb79140f73b30 ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0018 #5 [ffffb79140f73b08] _nfs41_proc_get_locations at ffffffffc0c73d53 [nfsv4] #6 [ffffb79140f73bf0] nfs4_proc_get_locations at ffffffffc0c83e90 [nfsv4] #7 [ffffb79140f73c60] nfs4_discover_trunking at ffffffffc0c83fb7 [nfsv4] #8 [ffffb79140f73cd8] nfs_probe_fsinfo at ffffffffc0c0f95f [nfs] #9 [ffffb79140f73da0] nfs_probe_server at ffffffffc0c1026a [nfs] RIP: 00007f6254fce26e RSP: 00007ffc69496ac8 RFLAGS: 00000246 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f6254fce26e RDX: 00005600220a82a0 RSI: 00005600220a64d0 RDI: 00005600220a6520 RBP: 00007ffc69496c50 R8: 00005600220a8710 R9: 003035322e323231 R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffc69496c50 R13: 00005600220a8440 R14: 0000000000000010 R15: 0000560020650ef9 ORIG_RAX: 00000000000000a5 CS: 0033 SS: 002b Fixes: c3ed222 ("NFSv4: Fix free of uninitialized nfs4_label on referral lookup.") Signed-off-by: Scott Mayhew <smayhew@redhat.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

When KASAN is enabled, below log might be dumped with Intel EHL hardware: [ 48.583597] ================================================================== [ 48.585921] BUG: KASAN: slab-out-of-bounds in hdac_hda_dai_hw_params+0x20a/0x22b [snd_soc_hdac_hda] [ 48.587995] Write of size 4 at addr ffff888103489708 by task pulseaudio/759 [ 48.589237] CPU: 2 PID: 759 Comm: pulseaudio Tainted: G U E 5.15.71-intel-ese-standard-lts #9 [ 48.591272] Hardware name: Intel Corporation Elkhart Lake Embedded Platform/ElkhartLake LPDDR4x T3 CRB, BIOS EHLSFWI1.R00.4251.A01.2206130432 06/13/2022 [ 48.593010] Call Trace: [ 48.593648] <TASK> [ 48.593852] dump_stack_lvl+0x34/0x48 [ 48.594404] print_address_description.constprop.0+0x1f/0x140 [ 48.595174] ? hdac_hda_dai_hw_params+0x20a/0x22b [snd_soc_hdac_hda] [ 48.595868] ? hdac_hda_dai_hw_params+0x20a/0x22b [snd_soc_hdac_hda] [ 48.596519] kasan_report.cold+0x7f/0x11b [ 48.597003] ? hdac_hda_dai_hw_params+0x20a/0x22b [snd_soc_hdac_hda] [ 48.597885] hdac_hda_dai_hw_params+0x20a/0x22b [snd_soc_hdac_hda] HDAC_LAST_DAI_ID is last index id, pcm buffer array size should be +1 to avoid out of bound access. Fixes: 608b8c3 ("ASoC: hdac_hda: add support for HDMI/DP as a HDA codec") Reviewed-by: Kai Vehmanen <kai.vehmanen@linux.intel.com> Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com> Signed-off-by: Junxiao Chang <junxiao.chang@intel.com> Signed-off-by: Furong Zhou <furong.zhou@intel.com> Link: https://lore.kernel.org/r/20221109234023.3111035-1-junxiao.chang@intel.com Signed-off-by: Mark Brown <broonie@kernel.org>

It seems that commit bc3c5e0 ("drm/i915/sseu: Don't try to store EU mask internally in UAPI format") exposed a potential out-of-bounds access, reported by UBSAN as following on a laptop with a gen 11 i915 card: UBSAN: array-index-out-of-bounds in drivers/gpu/drm/i915/gt/intel_sseu.c:65:27 index 6 is out of range for type 'u16 [6]' CPU: 2 PID: 165 Comm: systemd-udevd Not tainted 6.2.0-9-generic #9-Ubuntu Hardware name: Dell Inc. XPS 13 9300/077Y9N, BIOS 1.11.0 03/22/2022 Call Trace: <TASK> show_stack+0x4e/0x61 dump_stack_lvl+0x4a/0x6f dump_stack+0x10/0x18 ubsan_epilogue+0x9/0x3a __ubsan_handle_out_of_bounds.cold+0x42/0x47 gen11_compute_sseu_info+0x121/0x130 [i915] intel_sseu_info_init+0x15d/0x2b0 [i915] intel_gt_init_mmio+0x23/0x40 [i915] i915_driver_mmio_probe+0x129/0x400 [i915] ? intel_gt_probe_all+0x91/0x2e0 [i915] i915_driver_probe+0xe1/0x3f0 [i915] ? drm_privacy_screen_get+0x16d/0x190 [drm] ? acpi_dev_found+0x64/0x80 i915_pci_probe+0xac/0x1b0 [i915] ... According to the definition of sseu_dev_info, eu_mask->hsw is limited to a maximum of GEN_MAX_SS_PER_HSW_SLICE (6) sub-slices, but gen11_sseu_info_init() can potentially set 8 sub-slices, in the !IS_JSL_EHL(gt->i915) case. Fix this by reserving up to 8 slots for max_subslices in the eu_mask struct. Reported-by: Emil Renner Berthing <emil.renner.berthing@canonical.com> Signed-off-by: Andrea Righi <andrea.righi@canonical.com> Fixes: bc3c5e0 ("drm/i915/sseu: Don't try to store EU mask internally in UAPI format") Reviewed-by: Matt Roper <matthew.d.roper@intel.com> Signed-off-by: Matt Roper <matthew.d.roper@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20230220171858.131416-1-andrea.righi@canonical.com

It seems that commit bc3c5e0 ("drm/i915/sseu: Don't try to store EU mask internally in UAPI format") exposed a potential out-of-bounds access, reported by UBSAN as following on a laptop with a gen 11 i915 card: UBSAN: array-index-out-of-bounds in drivers/gpu/drm/i915/gt/intel_sseu.c:65:27 index 6 is out of range for type 'u16 [6]' CPU: 2 PID: 165 Comm: systemd-udevd Not tainted 6.2.0-9-generic #9-Ubuntu Hardware name: Dell Inc. XPS 13 9300/077Y9N, BIOS 1.11.0 03/22/2022 Call Trace: <TASK> show_stack+0x4e/0x61 dump_stack_lvl+0x4a/0x6f dump_stack+0x10/0x18 ubsan_epilogue+0x9/0x3a __ubsan_handle_out_of_bounds.cold+0x42/0x47 gen11_compute_sseu_info+0x121/0x130 [i915] intel_sseu_info_init+0x15d/0x2b0 [i915] intel_gt_init_mmio+0x23/0x40 [i915] i915_driver_mmio_probe+0x129/0x400 [i915] ? intel_gt_probe_all+0x91/0x2e0 [i915] i915_driver_probe+0xe1/0x3f0 [i915] ? drm_privacy_screen_get+0x16d/0x190 [drm] ? acpi_dev_found+0x64/0x80 i915_pci_probe+0xac/0x1b0 [i915] ... According to the definition of sseu_dev_info, eu_mask->hsw is limited to a maximum of GEN_MAX_SS_PER_HSW_SLICE (6) sub-slices, but gen11_sseu_info_init() can potentially set 8 sub-slices, in the !IS_JSL_EHL(gt->i915) case. Fix this by reserving up to 8 slots for max_subslices in the eu_mask struct. Reported-by: Emil Renner Berthing <emil.renner.berthing@canonical.com> Signed-off-by: Andrea Righi <andrea.righi@canonical.com> Fixes: bc3c5e0 ("drm/i915/sseu: Don't try to store EU mask internally in UAPI format") Reviewed-by: Matt Roper <matthew.d.roper@intel.com> Signed-off-by: Matt Roper <matthew.d.roper@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20230220171858.131416-1-andrea.righi@canonical.com (cherry picked from commit 3cba09a) Signed-off-by: Jani Nikula <jani.nikula@intel.com>

When a system with E810 with existing VFs gets rebooted the following hang may be observed. Pid 1 is hung in iavf_remove(), part of a network driver: PID: 1 TASK: ffff965400e5a340 CPU: 24 COMMAND: "systemd-shutdow" #0 [ffffaad04005fa50] __schedule at ffffffff8b3239cb #1 [ffffaad04005fae8] schedule at ffffffff8b323e2d #2 [ffffaad04005fb00] schedule_hrtimeout_range_clock at ffffffff8b32cebc #3 [ffffaad04005fb80] usleep_range_state at ffffffff8b32c930 #4 [ffffaad04005fbb0] iavf_remove at ffffffffc12b9b4c [iavf] #5 [ffffaad04005fbf0] pci_device_remove at ffffffff8add7513 #6 [ffffaad04005fc10] device_release_driver_internal at ffffffff8af08baa #7 [ffffaad04005fc40] pci_stop_bus_device at ffffffff8adcc5fc #8 [ffffaad04005fc60] pci_stop_and_remove_bus_device at ffffffff8adcc81e #9 [ffffaad04005fc70] pci_iov_remove_virtfn at ffffffff8adf9429 #10 [ffffaad04005fca8] sriov_disable at ffffffff8adf98e4 #11 [ffffaad04005fcc8] ice_free_vfs at ffffffffc04bb2c8 [ice] #12 [ffffaad04005fd10] ice_remove at ffffffffc04778fe [ice] #13 [ffffaad04005fd38] ice_shutdown at ffffffffc0477946 [ice] #14 [ffffaad04005fd50] pci_device_shutdown at ffffffff8add58f1 #15 [ffffaad04005fd70] device_shutdown at ffffffff8af05386 #16 [ffffaad04005fd98] kernel_restart at ffffffff8a92a870 #17 [ffffaad04005fda8] __do_sys_reboot at ffffffff8a92abd6 #18 [ffffaad04005fee0] do_syscall_64 at ffffffff8b317159 #19 [ffffaad04005ff08] __context_tracking_enter at ffffffff8b31b6fc #20 [ffffaad04005ff18] syscall_exit_to_user_mode at ffffffff8b31b50d #21 [ffffaad04005ff28] do_syscall_64 at ffffffff8b317169 #22 [ffffaad04005ff50] entry_SYSCALL_64_after_hwframe at ffffffff8b40009b RIP: 00007f1baa5c13d7 RSP: 00007fffbcc55a98 RFLAGS: 00000202 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f1baa5c13d7 RDX: 0000000001234567 RSI: 0000000028121969 RDI: 00000000fee1dead RBP: 00007fffbcc55ca0 R8: 0000000000000000 R9: 00007fffbcc54e90 R10: 00007fffbcc55050 R11: 0000000000000202 R12: 0000000000000005 R13: 0000000000000000 R14: 00007fffbcc55af0 R15: 0000000000000000 ORIG_RAX: 00000000000000a9 CS: 0033 SS: 002b During reboot all drivers PM shutdown callbacks are invoked. In iavf_shutdown() the adapter state is changed to __IAVF_REMOVE. In ice_shutdown() the call chain above is executed, which at some point calls iavf_remove(). However iavf_remove() expects the VF to be in one of the states __IAVF_RUNNING, __IAVF_DOWN or __IAVF_INIT_FAILED. If that's not the case it sleeps forever. So if iavf_shutdown() gets invoked before iavf_remove() the system will hang indefinitely because the adapter is already in state __IAVF_REMOVE. Fix this by returning from iavf_remove() if the state is __IAVF_REMOVE, as we already went through iavf_shutdown(). Fixes: 9745780 ("iavf: Add waiting so the port is initialized in remove") Fixes: a841733 ("iavf: Fix race condition between iavf_shutdown and iavf_remove") Reported-by: Marius Cornea <mcornea@redhat.com> Signed-off-by: Stefan Assmann <sassmann@kpanic.de> Reviewed-by: Michal Kubiak <michal.kubiak@intel.com> Tested-by: Rafal Romanowski <rafal.romanowski@intel.com> Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>

darky closed this as completed Nov 13, 2017

l-cd mentioned this issue Feb 27, 2019

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Is integrated graphics supported? #9

Is integrated graphics supported? #9

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darky commented Nov 10, 2017

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darky commented Nov 13, 2017