On 08/09/2016 10:15 AM, Oleg Nesterov wrote: > On 08/08, Bart Van Assche wrote: >> >> No external modules were loaded when I triggered the lockup > > Heh. Could you test the patch below? > > Oleg. > > --- x/kernel/sched/wait.c > +++ x/kernel/sched/wait.c > @@ -283,7 +283,7 @@ void abort_exclusive_wait(wait_queue_hea > if (!list_empty(&wait->task_list)) > list_del_init(&wait->task_list); > else if (waitqueue_active(q)) > - __wake_up_locked_key(q, mode, key); > + __wake_up_locked_key(q, TASK_NORMAL, key); > spin_unlock_irqrestore(&q->lock, flags); > } > EXPORT_SYMBOL(abort_exclusive_wait);
Hello Oleg, That patch looks interesting to me. Unfortunately even with that patch applied I still see lockups. These are the two lockups I have observed after I had applied your patch, rebuilt and reinstalled the kernel and rebooted the test server: [ 1548.018115] sysrq: SysRq : Show Blocked State [ 1548.018210] task PC stack pid father [ 1548.018677] systemd-udevd D ffff8803a9f13be8 0 29908 483 0x00000000 [ 1548.018792] ffff8803a9f13be8 ffffffff82584bd0 00ffffff8252b1b0 ffff88046f0569c0 [ 1548.018961] ffff88016c98b140 ffff8800757bc9c0 ffff8803a9f14000 ffff88046f0569c0 [ 1548.019131] 7fffffffffffffff ffffffff8161fcf0 ffff8803a9f13d50 ffff8803a9f13c00 [ 1548.019316] Call Trace: [ 1548.019415] [<ffffffff8161f567>] schedule+0x37/0x90 [ 1548.019464] [<ffffffff81623bbf>] schedule_timeout+0x27f/0x470 [ 1548.019758] [<ffffffff8161e93f>] io_schedule_timeout+0x9f/0x110 [ 1548.019808] [<ffffffff8161fd06>] bit_wait_io+0x16/0x60 [ 1548.019856] [<ffffffff8161f996>] __wait_on_bit+0x56/0x80 [ 1548.019906] [<ffffffff81152e1d>] wait_on_page_bit_killable+0xbd/0xc0 [ 1548.020006] [<ffffffff81152f50>] generic_file_read_iter+0x130/0x770 [ 1548.020158] [<ffffffff812134a0>] blkdev_read_iter+0x30/0x40 [ 1548.020209] [<ffffffff811d266b>] __vfs_read+0xbb/0x130 [ 1548.020258] [<ffffffff811d2a51>] vfs_read+0x91/0x130 [ 1548.020305] [<ffffffff811d3dd4>] SyS_read+0x44/0xa0 [ 1548.020354] [<ffffffff81624fa5>] entry_SYSCALL_64_fastpath+0x18/0xa8 [ 1050.892823] sysrq: SysRq : Show Blocked State [ 1050.892912] task PC stack pid father [ 1050.893333] systemd-udevd D ffff880449b3f838 0 17240 492 0x00000006 [ 1050.893974] Call Trace: [ 1050.894119] [<ffffffff8161f567>] schedule+0x37/0x90 [ 1050.894168] [<ffffffff81623bcf>] schedule_timeout+0x27f/0x470 [ 1050.894561] [<ffffffff8161e93f>] io_schedule_timeout+0x9f/0x110 [ 1050.894609] [<ffffffff8161fd16>] bit_wait_io+0x16/0x60 [ 1050.894657] [<ffffffff8161fb09>] __wait_on_bit_lock+0x49/0xa0 [ 1050.894705] [<ffffffff8114fe59>] __lock_page+0xb9/0xc0 [ 1050.894802] [<ffffffff81165d80>] truncate_inode_pages_range+0x3e0/0x760 [ 1050.895750] [<ffffffff81166110>] truncate_inode_pages+0x10/0x20 [ 1050.895799] [<ffffffff81212a10>] kill_bdev+0x30/0x40 [ 1050.895849] [<ffffffff81213d31>] __blkdev_put+0x71/0x360 [ 1050.895951] [<ffffffff81214069>] blkdev_put+0x49/0x170 [ 1050.895998] [<ffffffff812141b0>] blkdev_close+0x20/0x30 [ 1050.896047] [<ffffffff811d48d8>] __fput+0xe8/0x1f0 [ 1050.896094] [<ffffffff811d4a19>] ____fput+0x9/0x10 [ 1050.896141] [<ffffffff810842d3>] task_work_run+0x83/0xb0 [ 1050.896189] [<ffffffff8106606e>] do_exit+0x3ee/0xc40 [ 1050.896284] [<ffffffff8106694b>] do_group_exit+0x4b/0xc0 [ 1050.896331] [<ffffffff81073d9a>] get_signal+0x2ca/0x940 [ 1050.896425] [<ffffffff8101bf43>] do_signal+0x23/0x660 [ 1050.896626] [<ffffffff810022b3>] exit_to_usermode_loop+0x73/0xb0 [ 1050.896678] [<ffffffff81002cb0>] syscall_return_slowpath+0xb0/0xc0 [ 1050.896727] [<ffffffff81625033>] entry_SYSCALL_64_fastpath+0xa6/0xa8 Bart.
