[GIT PULL] io_uring updates for 5.17-rc #16

ammarfaizi2 · 2022-01-12T12:59:51Z

Hi Linus,

Here are the io_uring changes scheduled for this merge window. This pull
request contains:

- Support for prioritized work completions (Hao)

- Simplification of reissue (Pavel)

- Add support for CQE skip (Pavel)

- Memory leak fix going to 5.15-stable (Pavel)

- Re-write of internal poll. This both cleans up that code, and gets us
  ready to fix the POLLFREE issue (Pavel)

- Various cleanups (GuoYong, Pavel, Hao)

You'll hit a trivial merge conflict pulling this due to a function name
change in 5.16-late.

Please pull!


The following changes since commit 136057256686de39cc3a07c2e39ef6bc43003ff6:

  Linux 5.16-rc2 (2021-11-21 13:47:39 -0800)

are available in the Git repository at:

  git://git.kernel.dk/linux-block.git tags/for-5.17/io_uring-2022-01-11

for you to fetch changes up to 3cc7fdb9f90a25ae92250bf9e6cf3b9556b230e9:

  io_uring: fix not released cached task refs (2022-01-09 09:22:49 -0700)

----------------------------------------------------------------
for-5.17/io_uring-2022-01-11

----------------------------------------------------------------
GuoYong Zheng (2):
      io_uring: remove unused function parameter
      io_uring: remove redundant tab space

Hao Xu (9):
      io_uring: fix no lock protection for ctx->cq_extra
      io_uring: better to use REQ_F_IO_DRAIN for req->flags
      io_uring: move up io_put_kbuf() and io_put_rw_kbuf()
      io-wq: add helper to merge two wq_lists
      io_uring: add a priority tw list for irq completion work
      io_uring: add helper for task work execution code
      io_uring: split io_req_complete_post() and add a helper
      io_uring: batch completion in prior_task_list
      io_uring: code clean for some ctx usage

Pavel Begunkov (19):
      io_uring: simplify reissue in kiocb_done
      io_uring: improve send/recv error handling
      io_uring: clean __io_import_iovec()
      io_uring: improve argument types of kiocb_done()
      io_uring: clean cqe filling functions
      io_uring: add option to skip CQE posting
      io_uring: don't spinlock when not posting CQEs
      io_uring: disable drain with cqe skip
      io_uring: simplify selected buf handling
      io_uring: tweak iopoll CQE_SKIP event counting
      io_uring: reuse io_req_task_complete for timeouts
      io_uring: remove double poll on poll update
      io_uring: refactor poll update
      io_uring: move common poll bits
      io_uring: kill poll linking optimisation
      io_uring: poll rework
      io_uring: single shot poll removal optimisation
      io_uring: use completion batching for poll rem/upd
      io_uring: fix not released cached task refs

Ye Bin (1):
      io_uring: validate timespec for timeout removals

 fs/io-wq.h                    |   22 +
 fs/io_uring.c                 | 1140 +++++++++++++++++++++--------------------
 include/uapi/linux/io_uring.h |    4 +
 3 files changed, 612 insertions(+), 554 deletions(-)

-- 
Jens Axboe

Simplify failed resubmission prep in kiocb_done(), it's a bit ugly with conditional logic and hand handling cflags / select buffers. Instead, punt to tw and use io_req_task_complete() already handling all the cases. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/667c33484b05b612e9420e1b1d5f4dc46d0ee9ce.1637524285.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>

Hide all error handling under common if block, removes two extra ifs on the success path and keeps the handling more condensed. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/5761545158a12968f3caf30f747eea65ed75dfc1.1637524285.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>

Apparently, implicit 0 to NULL conversion with ERR_PTR is not recommended and makes some tooling like Smatch to complain. Handle it explicitly, compilers are perfectly capable to optimise it out. Link: https://lore.kernel.org/all/20211108134937.GA2863@kili/ Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/5c6ed369ad95075dab345df679f8677b8fe66656.1637524285.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>

kiocb_done() accepts a pointer to struct kiocb, pass struct io_kiocb (i.e. io_uring's request) instead so we can get rid of useless container_of(). Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/252016eed77806f58b48251a85cd8c645f900433.1637524285.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>

Split io_cqring_fill_event() into a couple of more targeted functions. The first on is io_fill_cqe_aux() for completions that are not associated with request completions and doing the ->cq_extra accounting. Examples are additional CQEs from multishot poll and rsrc notifications. The second is io_fill_cqe_req(), should be called when it's a normal request completion. Nothing more to it at the moment, will be used in later patches. The last one is inlined __io_fill_cqe() for a finer grained control, should be used with caution and in hottest places. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/59a9117a4a44fc9efcf04b3afa51e0d080f5943c.1636559119.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>

Emitting a CQE is expensive from the kernel perspective. Often, it's also not convenient for the userspace, spends some cycles on processing and just complicates the logic. A similar problems goes for linked requests, where we post an CQE for each request in the link. Introduce a new flags, IOSQE_CQE_SKIP_SUCCESS, trying to help with it. When set and a request completed successfully, it won't generate a CQE. When fails, it produces an CQE, but all following linked requests will be CQE-less, regardless whether they have IOSQE_CQE_SKIP_SUCCESS or not. The notion of "fail" is the same as for link failing-cancellation, where it's opcode dependent, and _usually_ result >= 0 is a success, but not always. Linked timeouts are a bit special. When the requests it's linked to was not attempted to be executed, e.g. failing linked requests, it follows the description above. Otherwise, whether a linked timeout will post a completion or not solely depends on IOSQE_CQE_SKIP_SUCCESS of that linked timeout request. Linked timeout never "fail" during execution, so for them it's unconditional. It's expected for users to not really care about the result of it but rely solely on the result of the master request. Another reason for such a treatment is that it's racy, and the timeout callback may be running awhile the master request posts its completion. use case 1: If one doesn't care about results of some requests, e.g. normal timeouts, just set IOSQE_CQE_SKIP_SUCCESS. Error result will still be posted and need to be handled. use case 2: Set IOSQE_CQE_SKIP_SUCCESS for all requests of a link but the last, and it'll post a completion only for the last one if everything goes right, otherwise there will be one only one CQE for the first failed request. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/0220fbe06f7cf99e6fc71b4297bb1cb6c0e89c2c.1636559119.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>

When no of queued for the batch completion requests need to post an CQE, see IOSQE_CQE_SKIP_SUCCESS, avoid grabbing ->completion_lock and other commit/post. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/8d4b4a08bca022cbe19af00266407116775b3e4d.1636559119.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>

Current IOSQE_IO_DRAIN implementation doesn't work well with CQE skipping and it's not allowed, otherwise some requests might be not executed until the ring is destroyed and the userspace would hang. Let's fail all drain requests after seeing IOSQE_CQE_SKIP_SUCCESS at least once. All drained requests prior to that will get run normally, so there should be no stalls. However, even though such mixing wouldn't lead to issues at the moment, it's still not allowed as the behaviour may change. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/bcf7164f8bf3eb54b7bb7b4fd119907fa4d4d43b.1636559119.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>

ctx->cq_extra should be protected by completion lock so that the req_need_defer() does the right check. Cc: stable@vger.kernel.org Signed-off-by: Hao Xu <haoxu@linux.alibaba.com> Link: https://lore.kernel.org/r/20211125092103.224502-2-haoxu@linux.alibaba.com Signed-off-by: Jens Axboe <axboe@kernel.dk>

It's better to use REQ_F_IO_DRAIN for req->flags rather than IOSQE_IO_DRAIN though they have same value. Signed-off-by: Hao Xu <haoxu@linux.alibaba.com> Link: https://lore.kernel.org/r/20211125092103.224502-3-haoxu@linux.alibaba.com Signed-off-by: Jens Axboe <axboe@kernel.dk>

Like commit f6223ff, timeout removal should also validate the timespec that is being passed in. Signed-off-by: Ye Bin <yebin10@huawei.com> Link: https://lore.kernel.org/r/20211129041537.1936270-1-yebin10@huawei.com Signed-off-by: Jens Axboe <axboe@kernel.dk>

Move them up to avoid explicit declaration. We will use them in later patches. Reviewed-by: Pavel Begunkov <asml.silence@gmail.com> Signed-off-by: Hao Xu <haoxu@linux.alibaba.com> Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/3631243d6fc4a79bbba0cd62597fc8cd5be95924.1638714983.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>

As selected buffers are now stored in a separate field in a request, get rid of rw/recv specific helpers and simplify the code. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/bd4a866d8d91b044f748c40efff9e4eacd07536e.1638714983.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>

When iopolling the userspace specifies the minimum number of "events" it expects. Previously, we had one CQE per request, so the definition of an "event" was unequivocal, but that's not more the case anymore with REQ_F_CQE_SKIP. Currently it counts the number of completed requests, replace it with the number of posted CQEs. This allows users of the "one CQE per link" scheme to wait for all N links in a single syscall, which is not possible without the patch and requires extra context switches. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/d5a965c4d2249827392037bbd0186f87fea49c55.1638714983.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>

With kbuf unification io_req_task_complete() is now a generic function, use it for timeout's tw completions. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/7142fa3cbaf3a4140d59bcba45cbe168cf40fac2.1638714983.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>

add a helper to merge two wq_lists, it will be useful in the next patches. Reviewed-by: Pavel Begunkov <asml.silence@gmail.com> Signed-off-by: Hao Xu <haoxu@linux.alibaba.com> Link: https://lore.kernel.org/r/20211207093951.247840-2-haoxu@linux.alibaba.com Signed-off-by: Jens Axboe <axboe@kernel.dk>

Now we have a lot of task_work users, some are just to complete a req and generate a cqe. Let's put the work to a new tw list which has a higher priority, so that it can be handled quickly and thus to reduce avg req latency and users can issue next round of sqes earlier. An explanatory case: origin timeline: submit_sqe-->irq-->add completion task_work -->run heavy work0~n-->run completion task_work now timeline: submit_sqe-->irq-->add completion task_work -->run completion task_work-->run heavy work0~n Limitation: this optimization is only for those that submission and reaping process are in different threads. Otherwise anyhow we have to submit new sqes after returning to userspace, then the order of TWs doesn't matter. Tested this patch(and the following ones) by manually replace __io_queue_sqe() in io_queue_sqe() by io_req_task_queue() to construct 'heavy' task works. Then test with fio: ioengine=io_uring sqpoll=1 thread=1 bs=4k direct=1 rw=randread time_based=1 runtime=600 randrepeat=0 group_reporting=1 filename=/dev/nvme0n1 Tried various iodepth. The peak IOPS for this patch is 710K, while the old one is 665K. For avg latency, difference shows when iodepth grow: depth and avg latency(usec): depth new old 1 7.05 7.10 2 8.47 8.60 4 10.42 10.42 8 13.78 13.22 16 27.41 24.33 32 49.40 53.08 64 102.53 103.36 128 196.98 205.61 256 372.99 414.88 512 747.23 791.30 1024 1472.59 1538.72 2048 3153.49 3329.01 4096 6387.86 6682.54 8192 12150.25 12774.14 16384 23085.58 26044.71 Signed-off-by: Hao Xu <haoxu@linux.alibaba.com> Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/20211207093951.247840-3-haoxu@linux.alibaba.com Signed-off-by: Jens Axboe <axboe@kernel.dk>

Add a helper for task work execution code. We will use it later. Reviewed-by: Pavel Begunkov <asml.silence@gmail.com> Signed-off-by: Hao Xu <haoxu@linux.alibaba.com> Link: https://lore.kernel.org/r/20211207093951.247840-4-haoxu@linux.alibaba.com Signed-off-by: Jens Axboe <axboe@kernel.dk>

Split io_req_complete_post(), this is a prep for the next patch. Signed-off-by: Hao Xu <haoxu@linux.alibaba.com> Link: https://lore.kernel.org/r/20211207093951.247840-5-haoxu@linux.alibaba.com Signed-off-by: Jens Axboe <axboe@kernel.dk>

In previous patches, we have already gathered some tw with io_req_task_complete() as callback in prior_task_list, let's complete them in batch while we cannot grab uring lock. In this way, we batch the req_complete_post path. Signed-off-by: Hao Xu <haoxu@linux.alibaba.com> Link: https://lore.kernel.org/r/20211208052125.351587-1-haoxu@linux.alibaba.com Reviewed-by: Pavel Begunkov <asml.silence@gmail.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>

There are some functions doing ctx = req->ctx while still using req->ctx, update those places. Signed-off-by: Hao Xu <haoxu@linux.alibaba.com> Link: https://lore.kernel.org/r/20211214055904.61772-1-haoxu@linux.alibaba.com Signed-off-by: Jens Axboe <axboe@kernel.dk>

Before updating a poll request we should remove it from poll queues, including the double poll entry. Fixes: b69de28 ("io_uring: allow events and user_data update of running poll requests") Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/ac39e7f80152613603b8a6cc29a2b6063ac2434f.1639605189.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>

Clean up io_poll_update() and unify cancellation paths for remove and update. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/5937138b6265a1285220e2fab1b28132c1d73ce3.1639605189.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>

Move some poll helpers/etc up, we'll need them there shortly Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/6c5c3dba24c86aad5cd389a54a8c7412e6a0621d.1639605189.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>

With IORING_FEAT_FAST_POLL in place, io_put_req_find_next() for poll requests doesn't make much sense, and in any case re-adding it shouldn't be a problem considering batching in tctx_task_work(). We can remove it. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/15699682bf81610ec901d4e79d6da64baa9f70be.1639605189.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>

It's not possible to go forward with the current state of io_uring polling, we need a more straightforward and easier synchronisation. There are a lot of problems with how it is at the moment, including missing events on rewait. The main idea here is to introduce a notion of request ownership while polling, no one but the owner can modify any part but ->poll_refs of struct io_kiocb, that grants us protection against all sorts of races. Main users of such exclusivity are poll task_work handler, so before queueing a tw one should have/acquire ownership, which will be handed off to the tw handler. The other user is __io_arm_poll_handler() do initial poll arming. It starts taking the ownership, so tw handlers won't be run until it's released later in the function after vfs_poll. note: also prevents races in __io_queue_proc(). Poll wake/etc. may not be able to get ownership, then they need to increase the poll refcount and the task_work should notice it and retry if necessary, see io_poll_check_events(). There is also IO_POLL_CANCEL_FLAG flag to notify that we want to kill request. It makes cancellations more reliable, enables double multishot polling, fixes double poll rewait, fixes missing poll events and fixes another bunch of races. Even though it adds some overhead for new refcounting, and there are a couple of nice performance wins: - no req->refs refcounting for poll requests anymore - if the data is already there (once measured for some test to be 1-2% of all apoll requests), it removes it doesn't add atomics and removes spin_lock/unlock pair. - works well with multishots, we don't do remove from queue / add to queue for each new poll event. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/6b652927c77ed9580ea4330ac5612f0e0848c946.1639605189.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>

We don't need to poll oneshot request if we've got a desired mask in io_poll_wake(), task_work will clean it up correctly, but as we already hold a wq spinlock, we can remove ourselves and save on additional spinlocking in io_poll_remove_entries(). Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/ee170a344a18c9ef36b554d806c64caadfd61c31.1639605189.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>

Use __io_req_complete() in io_poll_update(), so we can utilise completion batching for both update/remove request and the poll we're killing (if any). Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/e2bdc6c5abd9e9b80f09b86d8823eb1c780362cd.1639605189.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>

Parameter res2 is not used in __io_complete_rw, remove it. Fixes: 6b19b76 ("fs: get rid of the res2 iocb->ki_complete argument") Signed-off-by: GuoYong Zheng <zhenggy@chinatelecom.cn> Link: https://lore.kernel.org/r/1641377522-1851-1-git-send-email-zhenggy@chinatelecom.cn Signed-off-by: Jens Axboe <axboe@kernel.dk>

When show fdinfo, SqMask follow two tab space, which is inconsistent with other parameters. Remove one, so it lines up nicely. Signed-off-by: GuoYong Zheng <zhenggy@chinatelecom.cn> Link: https://lore.kernel.org/r/1641377585-1891-1-git-send-email-zhenggy@chinatelecom.cn Signed-off-by: Jens Axboe <axboe@kernel.dk>

[ Upstream commit 4e264be ] 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> Signed-off-by: Sasha Levin <sashal@kernel.org>

For a similar reason as commit f2c7ca8 ("drm/atomic-helper: Don't set deadline for modesets"), we need the crtc to be already active in order to compute a target vblank time for an async commit. Otherwise we get this splat reminding us that we are doing it wrong: ------------[ cut here ]------------ msm_dpu ae01000.mdp: drm_WARN_ON_ONCE(drm_drv_uses_atomic_modeset(dev)) WARNING: CPU: 7 PID: 1923 at drivers/gpu/drm/drm_vblank.c:728 drm_crtc_vblank_helper_get_vblank_timestamp_internal+0x148/0x370 Modules linked in: snd_seq_dummy snd_seq snd_seq_device bridge stp llc tun vhost_vsock vhost vhost_iotlb vmw_vsock_virtio_transport_common vsock uinput rfcomm algif_hash algif_skcipher af_alg veth venus_dec venus_enc cros_ec_typec typec qcom_spmi_temp_alarm qcom_spmi_adc_tm5 qcom_spmi_adc5 xt_cgroup qcom_vadc_common qcom_stats hci_uart btqca xt_MASQUERADE venus_core 8021q coresight_tmc coresight_funnel coresight_etm4x coresight_replicator snd_soc_lpass_sc7180 coresight snd_soc_sc7180 ip6table_nat fuse ath10k_snoc ath10k_core ath mac80211 iio_trig_sysfs bluetooth cfg80211 cros_ec_sensors cros_ec_sensors_core ecdh_generic industrialio_triggered_buffer ecc kfifo_buf cros_ec_sensorhub r8153_ecm cdc_ether usbnet r8152 mii lzo_rle lzo_compress zram hid_vivaldi hid_google_hammer hid_vivaldi_common joydev CPU: 7 PID: 1923 Comm: DrmThread Not tainted 5.15.107-18853-g3be267609a0b-dirty #16 a1ffc1a66e79c21c3536d8c9a42e819236e39714 Hardware name: Google Wormdingler rev1+ BOE panel board (DT) pstate: 60400009 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : drm_crtc_vblank_helper_get_vblank_timestamp_internal+0x148/0x370 lr : drm_crtc_vblank_helper_get_vblank_timestamp_internal+0x144/0x370 sp : ffffffc012e2b800 x29: ffffffc012e2b840 x28: ffffff8083676094 x27: ffffffc012e2bb28 x26: ffffff8084539800 x25: 0000000000000000 x24: ffffff8083676000 x23: ffffffd3c8cdc5a0 x22: ffffff80845b9d00 x21: ffffffc012e2b8b4 x20: ffffffc012e2b910 x19: 0000000000000001 x18: 0000000000000000 x17: 0000000000000000 x16: 0000000000000010 x15: ffffffd3c8451a88 x14: 0000000000000003 x13: 0000000000000004 x12: 0000000000000001 x11: c0000000ffffdfff x10: ffffffd3c973ef58 x9 : 8ea3526b3cc95900 x8 : 8ea3526b3cc95900 x7 : 0000000000000000 x6 : 000000000000003a x5 : ffffffd3c99676cd x4 : 0000000000000000 x3 : ffffffc012e2b4b8 x2 : ffffffc012e2b4c0 x1 : 00000000ffffdfff x0 : 0000000000000000 Call trace: drm_crtc_vblank_helper_get_vblank_timestamp_internal+0x148/0x370 drm_crtc_vblank_helper_get_vblank_timestamp+0x20/0x30 drm_crtc_get_last_vbltimestamp+0x68/0xb0 drm_crtc_next_vblank_start+0x5c/0xa8 msm_atomic_commit_tail+0x264/0x664 commit_tail+0xac/0x160 drm_atomic_helper_commit+0x160/0x168 drm_atomic_commit+0xfc/0x128 drm_atomic_helper_disable_plane+0x8c/0x110 __setplane_atomic+0x10c/0x138 drm_mode_cursor_common+0x3a8/0x410 drm_mode_cursor_ioctl+0x48/0x70 drm_ioctl_kernel+0xe0/0x158 drm_ioctl+0x25c/0x4d8 __arm64_sys_ioctl+0x98/0xd0 invoke_syscall+0x4c/0x100 el0_svc_common+0x98/0x104 do_el0_svc+0x30/0x90 el0_svc+0x20/0x50 el0t_64_sync_handler+0x78/0x108 el0t_64_sync+0x1a4/0x1a8 ---[ end trace a0f587e1ab9589e8 ]--- Fixes: 52ff0d3 ("drm/msm/atomic: Switch to vblank_start helper") Signed-off-by: Rob Clark <robdclark@chromium.org> Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org> Reviewed-by: Abhinav Kumar <quic_abhinavk@quicinc.com> Patchwork: https://patchwork.freedesktop.org/patch/532727/ Link: https://lore.kernel.org/r/20230418164158.549873-1-robdclark@gmail.com

Currently, the per cpu upcall counters are allocated after the vport is created and inserted into the system. This could lead to the datapath accessing the counters before they are allocated resulting in a kernel Oops. Here is an example: PID: 59693 TASK: ffff0005f4f51500 CPU: 0 COMMAND: "ovs-vswitchd" #0 [ffff80000a39b5b0] __switch_to at ffffb70f0629f2f4 #1 [ffff80000a39b5d0] __schedule at ffffb70f0629f5cc #2 [ffff80000a39b650] preempt_schedule_common at ffffb70f0629fa60 #3 [ffff80000a39b670] dynamic_might_resched at ffffb70f0629fb58 #4 [ffff80000a39b680] mutex_lock_killable at ffffb70f062a1388 #5 [ffff80000a39b6a0] pcpu_alloc at ffffb70f0594460c #6 [ffff80000a39b750] __alloc_percpu_gfp at ffffb70f05944e68 #7 [ffff80000a39b760] ovs_vport_cmd_new at ffffb70ee6961b90 [openvswitch] ... PID: 58682 TASK: ffff0005b2f0bf00 CPU: 0 COMMAND: "kworker/0:3" #0 [ffff80000a5d2f40] machine_kexec at ffffb70f056a0758 #1 [ffff80000a5d2f70] __crash_kexec at ffffb70f057e2994 #2 [ffff80000a5d3100] crash_kexec at ffffb70f057e2ad8 #3 [ffff80000a5d3120] die at ffffb70f0628234c #4 [ffff80000a5d31e0] die_kernel_fault at ffffb70f062828a8 #5 [ffff80000a5d3210] __do_kernel_fault at ffffb70f056a31f4 #6 [ffff80000a5d3240] do_bad_area at ffffb70f056a32a4 #7 [ffff80000a5d3260] do_translation_fault at ffffb70f062a9710 #8 [ffff80000a5d3270] do_mem_abort at ffffb70f056a2f74 #9 [ffff80000a5d32a0] el1_abort at ffffb70f06297dac #10 [ffff80000a5d32d0] el1h_64_sync_handler at ffffb70f06299b24 #11 [ffff80000a5d3410] el1h_64_sync at ffffb70f056812dc #12 [ffff80000a5d3430] ovs_dp_upcall at ffffb70ee6963c84 [openvswitch] #13 [ffff80000a5d3470] ovs_dp_process_packet at ffffb70ee6963fdc [openvswitch] #14 [ffff80000a5d34f0] ovs_vport_receive at ffffb70ee6972c78 [openvswitch] #15 [ffff80000a5d36f0] netdev_port_receive at ffffb70ee6973948 [openvswitch] #16 [ffff80000a5d3720] netdev_frame_hook at ffffb70ee6973a28 [openvswitch] #17 [ffff80000a5d3730] __netif_receive_skb_core.constprop.0 at ffffb70f06079f90 We moved the per cpu upcall counter allocation to the existing vport alloc and free functions to solve this. Fixes: 95637d9 ("net: openvswitch: release vport resources on failure") Fixes: 1933ea3 ("net: openvswitch: Add support to count upcall packets") Signed-off-by: Eelco Chaudron <echaudro@redhat.com> Reviewed-by: Simon Horman <simon.horman@corigine.com> Acked-by: Aaron Conole <aconole@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>

The cited commit holds encap tbl lock unconditionally when setting up dests. But it may cause the following deadlock: PID: 1063722 TASK: ffffa062ca5d0000 CPU: 13 COMMAND: "handler8" #0 [ffffb14de05b7368] __schedule at ffffffffa1d5aa91 #1 [ffffb14de05b7410] schedule at ffffffffa1d5afdb #2 [ffffb14de05b7430] schedule_preempt_disabled at ffffffffa1d5b528 #3 [ffffb14de05b7440] __mutex_lock at ffffffffa1d5d6cb #4 [ffffb14de05b74e8] mutex_lock_nested at ffffffffa1d5ddeb #5 [ffffb14de05b74f8] mlx5e_tc_tun_encap_dests_set at ffffffffc12f2096 [mlx5_core] #6 [ffffb14de05b7568] post_process_attr at ffffffffc12d9fc5 [mlx5_core] #7 [ffffb14de05b75a0] mlx5e_tc_add_fdb_flow at ffffffffc12de877 [mlx5_core] #8 [ffffb14de05b75f0] __mlx5e_add_fdb_flow at ffffffffc12e0eef [mlx5_core] #9 [ffffb14de05b7660] mlx5e_tc_add_flow at ffffffffc12e12f7 [mlx5_core] #10 [ffffb14de05b76b8] mlx5e_configure_flower at ffffffffc12e1686 [mlx5_core] #11 [ffffb14de05b7720] mlx5e_rep_indr_offload at ffffffffc12e3817 [mlx5_core] #12 [ffffb14de05b7730] mlx5e_rep_indr_setup_tc_cb at ffffffffc12e388a [mlx5_core] #13 [ffffb14de05b7740] tc_setup_cb_add at ffffffffa1ab2ba8 #14 [ffffb14de05b77a0] fl_hw_replace_filter at ffffffffc0bdec2f [cls_flower] #15 [ffffb14de05b7868] fl_change at ffffffffc0be6caa [cls_flower] #16 [ffffb14de05b7908] tc_new_tfilter at ffffffffa1ab71f0 [1031218.028143] wait_for_completion+0x24/0x30 [1031218.028589] mlx5e_update_route_decap_flows+0x9a/0x1e0 [mlx5_core] [1031218.029256] mlx5e_tc_fib_event_work+0x1ad/0x300 [mlx5_core] [1031218.029885] process_one_work+0x24e/0x510 Actually no need to hold encap tbl lock if there is no encap action. Fix it by checking if encap action exists or not before holding encap tbl lock. Fixes: 37c3b9f ("net/mlx5e: Prevent encap offload when neigh update is running") Signed-off-by: Chris Mi <cmi@nvidia.com> Reviewed-by: Vlad Buslov <vladbu@nvidia.com> Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>

kernel test robot reported slab-out-of-bounds access in strlen(). [0] Commit 06d4c8a ("af_unix: Fix fortify_panic() in unix_bind_bsd().") removed unix_mkname_bsd() call in unix_bind_bsd(). If sunaddr->sun_path is not terminated by user and we don't enable CONFIG_INIT_STACK_ALL_ZERO=y, strlen() will do the out-of-bounds access during file creation. Let's go back to strlen()-with-sockaddr_storage way and pack all 108 trickiness into unix_mkname_bsd() with bold comments. [0]: BUG: KASAN: slab-out-of-bounds in strlen (lib/string.c:?) Read of size 1 at addr ffff000015492777 by task fortify_strlen_/168 CPU: 0 PID: 168 Comm: fortify_strlen_ Not tainted 6.5.0-rc1-00333-g3329b603ebba #16 Hardware name: linux,dummy-virt (DT) Call trace: dump_backtrace (arch/arm64/kernel/stacktrace.c:235) show_stack (arch/arm64/kernel/stacktrace.c:242) dump_stack_lvl (lib/dump_stack.c:107) print_report (mm/kasan/report.c:365 mm/kasan/report.c:475) kasan_report (mm/kasan/report.c:590) __asan_report_load1_noabort (mm/kasan/report_generic.c:378) strlen (lib/string.c:?) getname_kernel (./include/linux/fortify-string.h:? fs/namei.c:226) kern_path_create (fs/namei.c:3926) unix_bind (net/unix/af_unix.c:1221 net/unix/af_unix.c:1324) __sys_bind (net/socket.c:1792) __arm64_sys_bind (net/socket.c:1801) invoke_syscall (arch/arm64/kernel/syscall.c:? arch/arm64/kernel/syscall.c:52) el0_svc_common (./include/linux/thread_info.h:127 arch/arm64/kernel/syscall.c:147) do_el0_svc (arch/arm64/kernel/syscall.c:189) el0_svc (./arch/arm64/include/asm/daifflags.h:28 arch/arm64/kernel/entry-common.c:133 arch/arm64/kernel/entry-common.c:144 arch/arm64/kernel/entry-common.c:648) el0t_64_sync_handler (arch/arm64/kernel/entry-common.c:?) el0t_64_sync (arch/arm64/kernel/entry.S:591) Allocated by task 168: kasan_set_track (mm/kasan/common.c:45 mm/kasan/common.c:52) kasan_save_alloc_info (mm/kasan/generic.c:512) __kasan_kmalloc (mm/kasan/common.c:383) __kmalloc (mm/slab_common.c:? mm/slab_common.c:998) unix_bind (net/unix/af_unix.c:257 net/unix/af_unix.c:1213 net/unix/af_unix.c:1324) __sys_bind (net/socket.c:1792) __arm64_sys_bind (net/socket.c:1801) invoke_syscall (arch/arm64/kernel/syscall.c:? arch/arm64/kernel/syscall.c:52) el0_svc_common (./include/linux/thread_info.h:127 arch/arm64/kernel/syscall.c:147) do_el0_svc (arch/arm64/kernel/syscall.c:189) el0_svc (./arch/arm64/include/asm/daifflags.h:28 arch/arm64/kernel/entry-common.c:133 arch/arm64/kernel/entry-common.c:144 arch/arm64/kernel/entry-common.c:648) el0t_64_sync_handler (arch/arm64/kernel/entry-common.c:?) el0t_64_sync (arch/arm64/kernel/entry.S:591) The buggy address belongs to the object at ffff000015492700 which belongs to the cache kmalloc-128 of size 128 The buggy address is located 0 bytes to the right of allocated 119-byte region [ffff000015492700, ffff000015492777) The buggy address belongs to the physical page: page:00000000aeab52ba refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x55492 anon flags: 0x3fffc0000000200(slab|node=0|zone=0|lastcpupid=0xffff) page_type: 0xffffffff() raw: 03fffc0000000200 ffff0000084018c0 fffffc00003d0e00 0000000000000005 raw: 0000000000000000 0000000080100010 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff000015492600: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff000015492680: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff000015492700: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 07 fc ^ ffff000015492780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff000015492800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb Fixes: 06d4c8a ("af_unix: Fix fortify_panic() in unix_bind_bsd().") Reported-by: kernel test robot <oliver.sang@intel.com> Closes: https://lore.kernel.org/netdev/202307262110.659e5e8-oliver.sang@intel.com/ Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Reviewed-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/20230726190828.47874-1-kuniyu@amazon.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>

Christoph Biedl reported early OOM on recent kernels: swapper: page allocation failure: order:0, mode:0x100(__GFP_ZERO), nodemask=(null) CPU: 0 PID: 0 Comm: swapper Not tainted 6.3.0-rc4+ #16 Hardware name: 9000/785/C3600 Backtrace: [<10408594>] show_stack+0x48/0x5c [<10e152d8>] dump_stack_lvl+0x48/0x64 [<10e15318>] dump_stack+0x24/0x34 [<105cf7f8>] warn_alloc+0x10c/0x1c8 [<105d068c>] __alloc_pages+0xbbc/0xcf8 [<105d0e4c>] __get_free_pages+0x28/0x78 [<105ad10c>] __pte_alloc_kernel+0x30/0x98 [<10406934>] set_fixmap+0xec/0xf4 [<10411ad4>] patch_map.constprop.0+0xa8/0xdc [<10411bb0>] __patch_text_multiple+0xa8/0x208 [<10411d78>] patch_text+0x30/0x48 [<1041246c>] arch_jump_label_transform+0x90/0xcc [<1056f734>] jump_label_update+0xd4/0x184 [<1056fc9c>] static_key_enable_cpuslocked+0xc0/0x110 [<1056fd08>] static_key_enable+0x1c/0x2c [<1011362c>] init_mem_debugging_and_hardening+0xdc/0xf8 [<1010141c>] start_kernel+0x5f0/0xa98 [<10105da8>] start_parisc+0xb8/0xe4 Mem-Info: active_anon:0 inactive_anon:0 isolated_anon:0 active_file:0 inactive_file:0 isolated_file:0 unevictable:0 dirty:0 writeback:0 slab_reclaimable:0 slab_unreclaimable:0 mapped:0 shmem:0 pagetables:0 sec_pagetables:0 bounce:0 kernel_misc_reclaimable:0 free:0 free_pcp:0 free_cma:0 Node 0 active_anon:0kB inactive_anon:0kB active_file:0kB inactive_file:0kB unevictable:0kB isolated(anon):0kB isolated(file):0kB mapped:0kB dirty:0kB writeback:0kB shmem:0kB +writeback_tmp:0kB kernel_stack:0kB pagetables:0kB sec_pagetables:0kB all_unreclaimable? no Normal free:0kB boost:0kB min:0kB low:0kB high:0kB reserved_highatomic:0KB active_anon:0kB inactive_anon:0kB active_file:0kB inactive_file:0kB unevictable:0kB writepending:0kB +present:1048576kB managed:1039360kB mlocked:0kB bounce:0kB free_pcp:0kB local_pcp:0kB free_cma:0kB lowmem_reserve[]: 0 0 Normal: 0*4kB 0*8kB 0*16kB 0*32kB 0*64kB 0*128kB 0*256kB 0*512kB 0*1024kB 0*2048kB 0*4096kB = 0kB 0 total pagecache pages 0 pages in swap cache Free swap = 0kB Total swap = 0kB 262144 pages RAM 0 pages HighMem/MovableOnly 2304 pages reserved Backtrace: [<10411d78>] patch_text+0x30/0x48 [<1041246c>] arch_jump_label_transform+0x90/0xcc [<1056f734>] jump_label_update+0xd4/0x184 [<1056fc9c>] static_key_enable_cpuslocked+0xc0/0x110 [<1056fd08>] static_key_enable+0x1c/0x2c [<1011362c>] init_mem_debugging_and_hardening+0xdc/0xf8 [<1010141c>] start_kernel+0x5f0/0xa98 [<10105da8>] start_parisc+0xb8/0xe4 Kernel Fault: Code=15 (Data TLB miss fault) at addr 0f7fe3c0 CPU: 0 PID: 0 Comm: swapper Not tainted 6.3.0-rc4+ #16 Hardware name: 9000/785/C3600 This happens because patching static key code temporarily maps it via fixmap and if it happens before page allocator is initialized set_fixmap() cannot allocate memory using pte_alloc_kernel(). Make sure that fixmap page tables are preallocated early so that pte_offset_kernel() in set_fixmap() never resorts to pte allocation. Signed-off-by: Mike Rapoport (IBM) <rppt@kernel.org> Acked-by: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Helge Deller <deller@gmx.de> Tested-by: Christoph Biedl <linux-kernel.bfrz@manchmal.in-ulm.de> Tested-by: John David Anglin <dave.anglin@bell.net> Cc: <stable@vger.kernel.org> # v6.4+

[ Upstream commit 0b0747d ] The following processes run into a deadlock. CPU 41 was waiting for CPU 29 to handle a CSD request while holding spinlock "crashdump_lock", but CPU 29 was hung by that spinlock with IRQs disabled. PID: 17360 TASK: ffff95c1090c5c40 CPU: 41 COMMAND: "mrdiagd" !# 0 [ffffb80edbf37b58] __read_once_size at ffffffff9b871a40 include/linux/compiler.h:185:0 !# 1 [ffffb80edbf37b58] atomic_read at ffffffff9b871a40 arch/x86/include/asm/atomic.h:27:0 !# 2 [ffffb80edbf37b58] dump_stack at ffffffff9b871a40 lib/dump_stack.c:54:0 # 3 [ffffb80edbf37b78] csd_lock_wait_toolong at ffffffff9b131ad5 kernel/smp.c:364:0 # 4 [ffffb80edbf37b78] __csd_lock_wait at ffffffff9b131ad5 kernel/smp.c:384:0 # 5 [ffffb80edbf37bf8] csd_lock_wait at ffffffff9b13267a kernel/smp.c:394:0 # 6 [ffffb80edbf37bf8] smp_call_function_many at ffffffff9b13267a kernel/smp.c:843:0 # 7 [ffffb80edbf37c50] smp_call_function at ffffffff9b13279d kernel/smp.c:867:0 # 8 [ffffb80edbf37c50] on_each_cpu at ffffffff9b13279d kernel/smp.c:976:0 # 9 [ffffb80edbf37c78] flush_tlb_kernel_range at ffffffff9b085c4b arch/x86/mm/tlb.c:742:0 #10 [ffffb80edbf37cb8] __purge_vmap_area_lazy at ffffffff9b23a1e0 mm/vmalloc.c:701:0 #11 [ffffb80edbf37ce0] try_purge_vmap_area_lazy at ffffffff9b23a2cc mm/vmalloc.c:722:0 #12 [ffffb80edbf37ce0] free_vmap_area_noflush at ffffffff9b23a2cc mm/vmalloc.c:754:0 #13 [ffffb80edbf37cf8] free_unmap_vmap_area at ffffffff9b23bb3b mm/vmalloc.c:764:0 #14 [ffffb80edbf37cf8] remove_vm_area at ffffffff9b23bb3b mm/vmalloc.c:1509:0 #15 [ffffb80edbf37d18] __vunmap at ffffffff9b23bb8a mm/vmalloc.c:1537:0 #16 [ffffb80edbf37d40] vfree at ffffffff9b23bc85 mm/vmalloc.c:1612:0 #17 [ffffb80edbf37d58] megasas_free_host_crash_buffer [megaraid_sas] at ffffffffc020b7f2 drivers/scsi/megaraid/megaraid_sas_fusion.c:3932:0 #18 [ffffb80edbf37d80] fw_crash_state_store [megaraid_sas] at ffffffffc01f804d drivers/scsi/megaraid/megaraid_sas_base.c:3291:0 #19 [ffffb80edbf37dc0] dev_attr_store at ffffffff9b56dd7b drivers/base/core.c:758:0 #20 [ffffb80edbf37dd0] sysfs_kf_write at ffffffff9b326acf fs/sysfs/file.c:144:0 #21 [ffffb80edbf37de0] kernfs_fop_write at ffffffff9b325fd4 fs/kernfs/file.c:316:0 #22 [ffffb80edbf37e20] __vfs_write at ffffffff9b29418a fs/read_write.c:480:0 #23 [ffffb80edbf37ea8] vfs_write at ffffffff9b294462 fs/read_write.c:544:0 #24 [ffffb80edbf37ee8] SYSC_write at ffffffff9b2946ec fs/read_write.c:590:0 #25 [ffffb80edbf37ee8] SyS_write at ffffffff9b2946ec fs/read_write.c:582:0 #26 [ffffb80edbf37f30] do_syscall_64 at ffffffff9b003ca9 arch/x86/entry/common.c:298:0 #27 [ffffb80edbf37f58] entry_SYSCALL_64 at ffffffff9ba001b1 arch/x86/entry/entry_64.S:238:0 PID: 17355 TASK: ffff95c1090c3d80 CPU: 29 COMMAND: "mrdiagd" !# 0 [ffffb80f2d3c7d30] __read_once_size at ffffffff9b0f2ab0 include/linux/compiler.h:185:0 !# 1 [ffffb80f2d3c7d30] native_queued_spin_lock_slowpath at ffffffff9b0f2ab0 kernel/locking/qspinlock.c:368:0 # 2 [ffffb80f2d3c7d58] pv_queued_spin_lock_slowpath at ffffffff9b0f244b arch/x86/include/asm/paravirt.h:674:0 # 3 [ffffb80f2d3c7d58] queued_spin_lock_slowpath at ffffffff9b0f244b arch/x86/include/asm/qspinlock.h:53:0 # 4 [ffffb80f2d3c7d68] queued_spin_lock at ffffffff9b8961a6 include/asm-generic/qspinlock.h:90:0 # 5 [ffffb80f2d3c7d68] do_raw_spin_lock_flags at ffffffff9b8961a6 include/linux/spinlock.h:173:0 # 6 [ffffb80f2d3c7d68] __raw_spin_lock_irqsave at ffffffff9b8961a6 include/linux/spinlock_api_smp.h:122:0 # 7 [ffffb80f2d3c7d68] _raw_spin_lock_irqsave at ffffffff9b8961a6 kernel/locking/spinlock.c:160:0 # 8 [ffffb80f2d3c7d88] fw_crash_buffer_store [megaraid_sas] at ffffffffc01f8129 drivers/scsi/megaraid/megaraid_sas_base.c:3205:0 # 9 [ffffb80f2d3c7dc0] dev_attr_store at ffffffff9b56dd7b drivers/base/core.c:758:0 #10 [ffffb80f2d3c7dd0] sysfs_kf_write at ffffffff9b326acf fs/sysfs/file.c:144:0 #11 [ffffb80f2d3c7de0] kernfs_fop_write at ffffffff9b325fd4 fs/kernfs/file.c:316:0 #12 [ffffb80f2d3c7e20] __vfs_write at ffffffff9b29418a fs/read_write.c:480:0 #13 [ffffb80f2d3c7ea8] vfs_write at ffffffff9b294462 fs/read_write.c:544:0 #14 [ffffb80f2d3c7ee8] SYSC_write at ffffffff9b2946ec fs/read_write.c:590:0 #15 [ffffb80f2d3c7ee8] SyS_write at ffffffff9b2946ec fs/read_write.c:582:0 #16 [ffffb80f2d3c7f30] do_syscall_64 at ffffffff9b003ca9 arch/x86/entry/common.c:298:0 #17 [ffffb80f2d3c7f58] entry_SYSCALL_64 at ffffffff9ba001b1 arch/x86/entry/entry_64.S:238:0 The lock is used to synchronize different sysfs operations, it doesn't protect any resource that will be touched by an interrupt. Consequently it's not required to disable IRQs. Replace the spinlock with a mutex to fix the deadlock. Signed-off-by: Junxiao Bi <junxiao.bi@oracle.com> Link: https://lore.kernel.org/r/20230828221018.19471-1-junxiao.bi@oracle.com Reviewed-by: Mike Christie <michael.christie@oracle.com> Cc: stable@vger.kernel.org Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Sasha Levin <sashal@kernel.org>

[ Upstream commit a154f5f ] The following call trace shows a deadlock issue due to recursive locking of mutex "device_mutex". First lock acquire is in target_for_each_device() and second in target_free_device(). PID: 148266 TASK: ffff8be21ffb5d00 CPU: 10 COMMAND: "iscsi_ttx" #0 [ffffa2bfc9ec3b18] __schedule at ffffffffa8060e7f #1 [ffffa2bfc9ec3ba0] schedule at ffffffffa8061224 #2 [ffffa2bfc9ec3bb8] schedule_preempt_disabled at ffffffffa80615ee #3 [ffffa2bfc9ec3bc8] __mutex_lock at ffffffffa8062fd7 #4 [ffffa2bfc9ec3c40] __mutex_lock_slowpath at ffffffffa80631d3 #5 [ffffa2bfc9ec3c50] mutex_lock at ffffffffa806320c #6 [ffffa2bfc9ec3c68] target_free_device at ffffffffc0935998 [target_core_mod] #7 [ffffa2bfc9ec3c90] target_core_dev_release at ffffffffc092f975 [target_core_mod] #8 [ffffa2bfc9ec3ca0] config_item_put at ffffffffa79d250f #9 [ffffa2bfc9ec3cd0] config_item_put at ffffffffa79d2583 #10 [ffffa2bfc9ec3ce0] target_devices_idr_iter at ffffffffc0933f3a [target_core_mod] #11 [ffffa2bfc9ec3d00] idr_for_each at ffffffffa803f6fc #12 [ffffa2bfc9ec3d60] target_for_each_device at ffffffffc0935670 [target_core_mod] #13 [ffffa2bfc9ec3d98] transport_deregister_session at ffffffffc0946408 [target_core_mod] #14 [ffffa2bfc9ec3dc8] iscsit_close_session at ffffffffc09a44a6 [iscsi_target_mod] #15 [ffffa2bfc9ec3df0] iscsit_close_connection at ffffffffc09a4a88 [iscsi_target_mod] #16 [ffffa2bfc9ec3df8] finish_task_switch at ffffffffa76e5d07 #17 [ffffa2bfc9ec3e78] iscsit_take_action_for_connection_exit at ffffffffc0991c23 [iscsi_target_mod] #18 [ffffa2bfc9ec3ea0] iscsi_target_tx_thread at ffffffffc09a403b [iscsi_target_mod] #19 [ffffa2bfc9ec3f08] kthread at ffffffffa76d8080 #20 [ffffa2bfc9ec3f50] ret_from_fork at ffffffffa8200364 Fixes: 36d4cb4 ("scsi: target: Avoid that EXTENDED COPY commands trigger lock inversion") Signed-off-by: Junxiao Bi <junxiao.bi@oracle.com> Link: https://lore.kernel.org/r/20230918225848.66463-1-junxiao.bi@oracle.com Reviewed-by: Mike Christie <michael.christie@oracle.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Sasha Levin <sashal@kernel.org>

vhost_worker will call tun call backs to receive packets. If too many illegal packets arrives, tun_do_read will keep dumping packet contents. When console is enabled, it will costs much more cpu time to dump packet and soft lockup will be detected. net_ratelimit mechanism can be used to limit the dumping rate. PID: 33036 TASK: ffff949da6f20000 CPU: 23 COMMAND: "vhost-32980" #0 [fffffe00003fce50] crash_nmi_callback at ffffffff89249253 #1 [fffffe00003fce58] nmi_handle at ffffffff89225fa3 #2 [fffffe00003fceb0] default_do_nmi at ffffffff8922642e #3 [fffffe00003fced0] do_nmi at ffffffff8922660d #4 [fffffe00003fcef0] end_repeat_nmi at ffffffff89c01663 [exception RIP: io_serial_in+20] RIP: ffffffff89792594 RSP: ffffa655314979e8 RFLAGS: 00000002 RAX: ffffffff89792500 RBX: ffffffff8af428a0 RCX: 0000000000000000 RDX: 00000000000003fd RSI: 0000000000000005 RDI: ffffffff8af428a0 RBP: 0000000000002710 R8: 0000000000000004 R9: 000000000000000f R10: 0000000000000000 R11: ffffffff8acbf64f R12: 0000000000000020 R13: ffffffff8acbf698 R14: 0000000000000058 R15: 0000000000000000 ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0018 #5 [ffffa655314979e8] io_serial_in at ffffffff89792594 #6 [ffffa655314979e8] wait_for_xmitr at ffffffff89793470 #7 [ffffa65531497a08] serial8250_console_putchar at ffffffff897934f6 #8 [ffffa65531497a20] uart_console_write at ffffffff8978b605 #9 [ffffa65531497a48] serial8250_console_write at ffffffff89796558 #10 [ffffa65531497ac8] console_unlock at ffffffff89316124 #11 [ffffa65531497b10] vprintk_emit at ffffffff89317c07 #12 [ffffa65531497b68] printk at ffffffff89318306 #13 [ffffa65531497bc8] print_hex_dump at ffffffff89650765 #14 [ffffa65531497ca8] tun_do_read at ffffffffc0b06c27 [tun] #15 [ffffa65531497d38] tun_recvmsg at ffffffffc0b06e34 [tun] #16 [ffffa65531497d68] handle_rx at ffffffffc0c5d682 [vhost_net] #17 [ffffa65531497ed0] vhost_worker at ffffffffc0c644dc [vhost] #18 [ffffa65531497f10] kthread at ffffffff892d2e72 #19 [ffffa65531497f50] ret_from_fork at ffffffff89c0022f Fixes: ef3db4a ("tun: avoid BUG, dump packet on GSO errors") Signed-off-by: Lei Chen <lei.chen@smartx.com> Reviewed-by: Willem de Bruijn <willemb@google.com> Acked-by: Jason Wang <jasowang@redhat.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Acked-by: Michael S. Tsirkin <mst@redhat.com> Link: https://lore.kernel.org/r/20240415020247.2207781-1-lei.chen@smartx.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>

isilence and others added 30 commits November 23, 2021 12:24

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[GIT PULL] io_uring updates for 5.17-rc #16

[GIT PULL] io_uring updates for 5.17-rc #16

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[GIT PULL] io_uring updates for 5.17-rc #16

[GIT PULL] io_uring updates for 5.17-rc #16

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ammarfaizi2 commented Jan 12, 2022 • edited Loading

ammarfaizi2 commented Jan 12, 2022 •

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