ibmvscsis: clean up functions #25
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This patch removes forward declarations and re-organizes the functions within the driver. This patch also fixes MAINTAINERS for ibmvscsis. Signed-off-by: bryantly <bryantly@linux.vnet.ibm.com>
bgly
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Jun 14, 2016
The 'schedstats=enable' option doesn't work, and also produces the following warning during boot: WARNING: CPU: 0 PID: 0 at /home/jpoimboe/git/linux/kernel/jump_label.c:61 static_key_slow_inc+0x8c/0xa0 static_key_slow_inc used before call to jump_label_init Modules linked in: CPU: 0 PID: 0 Comm: swapper Not tainted 4.7.0-rc1+ #25 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.8.1-20150318_183358- 04/01/2014 0000000000000086 3ae3475a4bea95d4 ffffffff81e03da8 ffffffff8143fc83 ffffffff81e03df8 0000000000000000 ffffffff81e03de8 ffffffff810b1ffb 0000003d00000096 ffffffff823514d0 ffff88007ff197c8 0000000000000000 Call Trace: [<ffffffff8143fc83>] dump_stack+0x85/0xc2 [<ffffffff810b1ffb>] __warn+0xcb/0xf0 [<ffffffff810b207f>] warn_slowpath_fmt+0x5f/0x80 [<ffffffff811e9c0c>] static_key_slow_inc+0x8c/0xa0 [<ffffffff810e07c6>] static_key_enable+0x16/0x40 [<ffffffff8216d633>] setup_schedstats+0x29/0x94 [<ffffffff82148a05>] unknown_bootoption+0x89/0x191 [<ffffffff810d8617>] parse_args+0x297/0x4b0 [<ffffffff82148d61>] start_kernel+0x1d8/0x4a9 [<ffffffff8214897c>] ? set_init_arg+0x55/0x55 [<ffffffff82148120>] ? early_idt_handler_array+0x120/0x120 [<ffffffff821482db>] x86_64_start_reservations+0x2f/0x31 [<ffffffff82148427>] x86_64_start_kernel+0x14a/0x16d The problem is that it tries to update the 'sched_schedstats' static key before jump labels have been initialized. Changing jump_label_init() to be called earlier before parse_early_param() wouldn't fix it: it would still fail trying to poke_text() because mm isn't yet initialized. Instead, just create a temporary '__sched_schedstats' variable which can be copied to the static key later during sched_init() after jump labels have been initialized. Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Matt Fleming <matt@codeblueprint.co.uk> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Fixes: cb25176 ("sched/debug: Make schedstats a runtime tunable that is disabled by default") Link: http://lkml.kernel.org/r/453775fe3433bed65731a583e228ccea806d18cd.1465322027.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
bgly
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Jun 21, 2016
commit f5cdedd upstream. We can handle the special case of num_stripes == 0 directly inside btrfs_read_sys_array. The BUG_ON in btrfs_chunk_item_size is there to catch other unhandled cases where we fail to validate external data. A crafted or corrupted image crashes at mount time: BTRFS: device fsid 9006933e-2a9a-44f0-917f-514252aeec2c devid 1 transid 7 /dev/loop0 BTRFS info (device loop0): disk space caching is enabled BUG: failure at fs/btrfs/ctree.h:337/btrfs_chunk_item_size()! Kernel panic - not syncing: BUG! CPU: 0 PID: 313 Comm: mount Not tainted 4.2.5-00657-ge047887-dirty #25 Stack: 637af890 60062489 602aeb2e 604192ba 60387961 00000011 637af8a0 6038a835 637af9c0 6038776b 634ef32b 00000000 Call Trace: [<6001c86d>] show_stack+0xfe/0x15b [<6038a835>] dump_stack+0x2a/0x2c [<6038776b>] panic+0x13e/0x2b3 [<6020f099>] btrfs_read_sys_array+0x25d/0x2ff [<601cfbbe>] open_ctree+0x192d/0x27af [<6019c2c1>] btrfs_mount+0x8f5/0xb9a [<600bc9a7>] mount_fs+0x11/0xf3 [<600d5167>] vfs_kern_mount+0x75/0x11a [<6019bcb0>] btrfs_mount+0x2e4/0xb9a [<600bc9a7>] mount_fs+0x11/0xf3 [<600d5167>] vfs_kern_mount+0x75/0x11a [<600d710b>] do_mount+0xa35/0xbc9 [<600d7557>] SyS_mount+0x95/0xc8 [<6001e884>] handle_syscall+0x6b/0x8e Reported-by: Jiri Slaby <jslaby@suse.com> Reported-by: Vegard Nossum <vegard.nossum@oracle.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
bgly
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Aug 18, 2017
BugLink: http://bugs.launchpad.net/bugs/1675789 [ Upstream commit 45caeaa ] As Eric Dumazet pointed out this also needs to be fixed in IPv6. v2: Contains the IPv6 tcp/Ipv6 dccp patches as well. We have seen a few incidents lately where a dst_enty has been freed with a dangling TCP socket reference (sk->sk_dst_cache) pointing to that dst_entry. If the conditions/timings are right a crash then ensues when the freed dst_entry is referenced later on. A Common crashing back trace is: #8 [] page_fault at ffffffff8163e648 [exception RIP: __tcp_ack_snd_check+74] . . #9 [] tcp_rcv_established at ffffffff81580b64 #10 [] tcp_v4_do_rcv at ffffffff8158b54a #11 [] tcp_v4_rcv at ffffffff8158cd02 #12 [] ip_local_deliver_finish at ffffffff815668f4 #13 [] ip_local_deliver at ffffffff81566bd9 #14 [] ip_rcv_finish at ffffffff8156656d #15 [] ip_rcv at ffffffff81566f06 #16 [] __netif_receive_skb_core at ffffffff8152b3a2 #17 [] __netif_receive_skb at ffffffff8152b608 #18 [] netif_receive_skb at ffffffff8152b690 #19 [] vmxnet3_rq_rx_complete at ffffffffa015eeaf [vmxnet3] #20 [] vmxnet3_poll_rx_only at ffffffffa015f32a [vmxnet3] #21 [] net_rx_action at ffffffff8152bac2 #22 [] __do_softirq at ffffffff81084b4f #23 [] call_softirq at ffffffff8164845c #24 [] do_softirq at ffffffff81016fc5 #25 [] irq_exit at ffffffff81084ee5 #26 [] do_IRQ at ffffffff81648ff8 Of course it may happen with other NIC drivers as well. It's found the freed dst_entry here: 224 static bool tcp_in_quickack_mode(struct sock *sk)↩ 225 {↩ 226 ▹ const struct inet_connection_sock *icsk = inet_csk(sk);↩ 227 ▹ const struct dst_entry *dst = __sk_dst_get(sk);↩ 228 ↩ 229 ▹ return (dst && dst_metric(dst, RTAX_QUICKACK)) ||↩ 230 ▹ ▹ (icsk->icsk_ack.quick && !icsk->icsk_ack.pingpong);↩ 231 }↩ But there are other backtraces attributed to the same freed dst_entry in netfilter code as well. All the vmcores showed 2 significant clues: - Remote hosts behind the default gateway had always been redirected to a different gateway. A rtable/dst_entry will be added for that host. Making more dst_entrys with lower reference counts. Making this more probable. - All vmcores showed a postitive LockDroppedIcmps value, e.g: LockDroppedIcmps 267 A closer look at the tcp_v4_err() handler revealed that do_redirect() will run regardless of whether user space has the socket locked. This can result in a race condition where the same dst_entry cached in sk->sk_dst_entry can be decremented twice for the same socket via: do_redirect()->__sk_dst_check()-> dst_release(). Which leads to the dst_entry being prematurely freed with another socket pointing to it via sk->sk_dst_cache and a subsequent crash. To fix this skip do_redirect() if usespace has the socket locked. Instead let the redirect take place later when user space does not have the socket locked. The dccp/IPv6 code is very similar in this respect, so fixing it there too. As Eric Garver pointed out the following commit now invalidates routes. Which can set the dst->obsolete flag so that ipv4_dst_check() returns null and triggers the dst_release(). Fixes: ceb3320 ("ipv4: Kill routes during PMTU/redirect updates.") Cc: Eric Garver <egarver@redhat.com> Cc: Hannes Sowa <hsowa@redhat.com> Signed-off-by: Jon Maxwell <jmaxwell37@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Tim Gardner <tim.gardner@canonical.com> Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>
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This patch removes forward declarations and re-organizes the
functions within the driver. This patch also fixes MAINTAINERS
for ibmvscsis.
Signed-off-by: bryantly bryantly@linux.vnet.ibm.com