Hi again, On 20. 08. 20 0:58, Chris Murphy wrote: > The problem here I think is that /proc/pid/stack is empty. You might > have to hammer on it a bunch of times to get a stack. I can't tell if > the sysrq+w is enough information to conclusively tell if this is > strictly an md problem or if there's something else going on. > > But I do see in the sysrq+w evidence of a Btrfs snapshot happening, > which will result in a flush of the file system. Since the mdadm raid > journal is on two SSDs which should be fast enough to accept the > metadata changes before actually doing the flush. We were lucky to dump some stacks yesterday, when the issue happened again. In `sysrq.log`, there is an dmesg/kern.log output of echo w > /proc/sysrq-trigger command, when `md1_raid6` started to consume 100% CPU and all btrfs-snapshot-related commands stuck in the *disk sleep* state. We had issued sysrq+w command several times and I have included all unique tasks appeared there. In `stack_md1_reclaim.txt`, `stack_btrfs-transacti.txt` and `stack_btrfs*.txt`, there are outputs of cat /proc/<pid>/stack of given processes during the same time. The output is still the same when we issued this command several times. In `stack_md1_raid6-[0-3].txt`, there are outputs of the same command where pid is `md1_raid6` process id. We issued that several time and the output differs a bit sometimes. If I get it right, differs only in instruction offset of given functions. I include all the combinations we encounter for case it matters. We have dumped stack of this process in a while-true cycle just after we perform a manual "unstuck" workaround (I described this action in the first e-mail). I can send it to the mailing list as well if needed. I hope these outputs include what you, Song, requested on July the 30th (and I hope it's ok to continue in this thread) On 30. 07. 20 8:45, Song Liu wrote: >> On Jul 29, 2020, at 2:06 PM, Guoqing Jiang wrote: >> >> Hi, >> >> On 7/22/20 10:47 PM, Vojtech Myslivec wrote: >>> 1. What should be the cause of this problem? >> >> Just a quick glance based on the stacks which you attached, I guess >> it could be a deadlock issue of raid5 cache super write. >> >> Maybe the commit 8e018c21da3f ("raid5-cache: fix a deadlock in >> superblock write") didn't fix the problem completely. Cc Song. >> >> And I am curious why md thread is not waked if mddev_trylock fails, >> you can give it a try but I can't promise it helps ... > > Thanks Guoqing! > > I am not sure whether we hit the mddev_trylock() failure. Looks like > the md1_raid6 thread is already running at 100%. > > A few questions: > > 1. I see wbt_wait in the stack trace. Are we using write back > throttling here? > 2. Could you please get the /proc/<pid>/stack for <pid> of md1_raid6? > We may want to sample it multiple times. > > Thanks, > Song Thanks, Vojtech and Michal
[<0>] ops_run_io+0x40/0xd80 [raid456] [<0>] handle_stripe+0xc32/0x2230 [raid456] [<0>] handle_active_stripes.isra.71+0x3b8/0x590 [raid456] [<0>] raid5d+0x392/0x5b0 [raid456] [<0>] md_thread+0x94/0x150 [md_mod] [<0>] kthread+0x112/0x130 [<0>] ret_from_fork+0x22/0x40
[<0>] ops_run_io+0x40/0xd80 [raid456] [<0>] handle_stripe+0x136/0x2230 [raid456] [<0>] handle_active_stripes.isra.71+0x3b8/0x590 [raid456] [<0>] raid5d+0x392/0x5b0 [raid456] [<0>] md_thread+0x94/0x150 [md_mod] [<0>] kthread+0x112/0x130 [<0>] ret_from_fork+0x22/0x40
[<0>] ops_run_io+0x40/0xd80 [raid456] [<0>] handle_stripe+0xc32/0x2230 [raid456] [<0>] handle_active_stripes.isra.71+0x485/0x590 [raid456] [<0>] raid5d+0x392/0x5b0 [raid456] [<0>] md_thread+0x94/0x150 [md_mod] [<0>] kthread+0x112/0x130 [<0>] ret_from_fork+0x22/0x40
[<0>] ops_run_io+0x40/0xd80 [raid456] [<0>] handle_stripe+0x136/0x2230 [raid456] [<0>] handle_active_stripes.isra.71+0x420/0x590 [raid456] [<0>] raid5d+0x392/0x5b0 [raid456] [<0>] md_thread+0x94/0x150 [md_mod] [<0>] kthread+0x112/0x130 [<0>] ret_from_fork+0x22/0x40
[<0>] rq_qos_wait+0xfa/0x170 [<0>] wbt_wait+0x98/0xe0 [<0>] __rq_qos_throttle+0x23/0x30 [<0>] blk_mq_make_request+0x12a/0x5d0 [<0>] generic_make_request+0xcf/0x310 [<0>] submit_bio+0x42/0x1c0 [<0>] md_update_sb.part.71+0x3c0/0x8f0 [md_mod] [<0>] r5l_do_reclaim+0x32a/0x3b0 [raid456] [<0>] md_thread+0x94/0x150 [md_mod] [<0>] kthread+0x112/0x130 [<0>] ret_from_fork+0x22/0x40
[<0>] wait_on_page_bit+0x15c/0x230 [<0>] __filemap_fdatawait_range+0x89/0xf0 [<0>] filemap_fdatawait_range+0xe/0x20 [<0>] __btrfs_wait_marked_extents.isra.19+0xc2/0x100 [btrfs] [<0>] btrfs_write_and_wait_transaction.isra.23+0x67/0xd0 [btrfs] [<0>] btrfs_commit_transaction+0x755/0xa50 [btrfs] [<0>] transaction_kthread+0x144/0x170 [btrfs] [<0>] kthread+0x112/0x130 [<0>] ret_from_fork+0x22/0x40
[<0>] do_wait+0x1c7/0x230 [<0>] kernel_wait4+0xa6/0x140 [<0>] __do_sys_wait4+0x83/0x90 [<0>] do_syscall_64+0x52/0x170 [<0>] entry_SYSCALL_64_after_hwframe+0x44/0xa9
[<0>] rwsem_down_write_slowpath+0x329/0x4e0 [<0>] btrfs_delete_subvolume+0x90/0x5f0 [btrfs] [<0>] btrfs_ioctl_snap_destroy+0x5b3/0x6f0 [btrfs] [<0>] btrfs_ioctl+0xa5f/0x2ef0 [btrfs] [<0>] ksys_ioctl+0x86/0xc0 [<0>] __x64_sys_ioctl+0x16/0x20 [<0>] do_syscall_64+0x52/0x170 [<0>] entry_SYSCALL_64_after_hwframe+0x44/0xa9
[<0>] rwsem_down_write_slowpath+0x329/0x4e0 [<0>] btrfs_delete_subvolume+0x90/0x5f0 [btrfs] [<0>] btrfs_ioctl_snap_destroy+0x5b3/0x6f0 [btrfs] [<0>] btrfs_ioctl+0xa5f/0x2ef0 [btrfs] [<0>] ksys_ioctl+0x86/0xc0 [<0>] __x64_sys_ioctl+0x16/0x20 [<0>] do_syscall_64+0x52/0x170 [<0>] entry_SYSCALL_64_after_hwframe+0x44/0xa9
[<0>] rwsem_down_write_slowpath+0x329/0x4e0 [<0>] btrfs_delete_subvolume+0x90/0x5f0 [btrfs] [<0>] btrfs_ioctl_snap_destroy+0x5b3/0x6f0 [btrfs] [<0>] btrfs_ioctl+0xa5f/0x2ef0 [btrfs] [<0>] ksys_ioctl+0x86/0xc0 [<0>] __x64_sys_ioctl+0x16/0x20 [<0>] do_syscall_64+0x52/0x170 [<0>] entry_SYSCALL_64_after_hwframe+0x44/0xa9
[<0>] wait_for_commit+0x58/0x80 [btrfs] [<0>] btrfs_commit_transaction+0x169/0xa50 [btrfs] [<0>] btrfs_mksubvol+0x2e9/0x450 [btrfs] [<0>] __btrfs_ioctl_snap_create+0x167/0x170 [btrfs] [<0>] btrfs_ioctl_snap_create_v2+0xc5/0xe0 [btrfs] [<0>] btrfs_ioctl+0xf61/0x2ef0 [btrfs] [<0>] ksys_ioctl+0x86/0xc0 [<0>] __x64_sys_ioctl+0x16/0x20 [<0>] do_syscall_64+0x52/0x170 [<0>] entry_SYSCALL_64_after_hwframe+0x44/0xa9
[Tue Aug 25 16:41:16 2020] sysrq: Show Blocked State [Tue Aug 25 16:41:16 2020] task PC stack pid father [Tue Aug 25 16:41:16 2020] md1_reclaim D 0 806 2 0x80004000 [Tue Aug 25 16:41:16 2020] Call Trace: [Tue Aug 25 16:41:16 2020] __schedule+0x2dd/0x710 [Tue Aug 25 16:41:16 2020] ? __switch_to_asm+0x34/0x70 [Tue Aug 25 16:41:16 2020] ? __switch_to_asm+0x34/0x70 [Tue Aug 25 16:41:16 2020] ? wbt_exit+0x30/0x30 [Tue Aug 25 16:41:16 2020] ? __wbt_done+0x30/0x30 [Tue Aug 25 16:41:16 2020] schedule+0x40/0xb0 [Tue Aug 25 16:41:16 2020] io_schedule+0x12/0x40 [Tue Aug 25 16:41:16 2020] rq_qos_wait+0xfa/0x170 [Tue Aug 25 16:41:16 2020] ? __switch_to_asm+0x34/0x70 [Tue Aug 25 16:41:16 2020] ? karma_partition+0x1e0/0x1e0 [Tue Aug 25 16:41:16 2020] ? wbt_exit+0x30/0x30 [Tue Aug 25 16:41:16 2020] wbt_wait+0x98/0xe0 [Tue Aug 25 16:41:16 2020] __rq_qos_throttle+0x23/0x30 [Tue Aug 25 16:41:16 2020] blk_mq_make_request+0x12a/0x5d0 [Tue Aug 25 16:41:16 2020] generic_make_request+0xcf/0x310 [Tue Aug 25 16:41:16 2020] submit_bio+0x42/0x1c0 [Tue Aug 25 16:41:16 2020] ? md_super_write.part.70+0x98/0x120 [md_mod] [Tue Aug 25 16:41:16 2020] md_update_sb.part.71+0x3c0/0x8f0 [md_mod] [Tue Aug 25 16:41:16 2020] r5l_do_reclaim+0x32a/0x3b0 [raid456] [Tue Aug 25 16:41:16 2020] ? schedule_timeout+0x162/0x340 [Tue Aug 25 16:41:16 2020] ? prepare_to_wait_event+0xb6/0x140 [Tue Aug 25 16:41:16 2020] ? md_register_thread+0xd0/0xd0 [md_mod] [Tue Aug 25 16:41:16 2020] md_thread+0x94/0x150 [md_mod] [Tue Aug 25 16:41:16 2020] ? finish_wait+0x80/0x80 [Tue Aug 25 16:41:16 2020] kthread+0x112/0x130 [Tue Aug 25 16:41:16 2020] ? kthread_park+0x80/0x80 [Tue Aug 25 16:41:16 2020] ret_from_fork+0x22/0x40 [Tue Aug 25 16:41:16 2020] btrfs-transacti D 0 893 2 0x80004000 [Tue Aug 25 16:41:16 2020] Call Trace: [Tue Aug 25 16:41:16 2020] __schedule+0x2dd/0x710 [Tue Aug 25 16:41:16 2020] schedule+0x40/0xb0 [Tue Aug 25 16:41:16 2020] io_schedule+0x12/0x40 [Tue Aug 25 16:41:16 2020] wait_on_page_bit+0x15c/0x230 [Tue Aug 25 16:41:16 2020] ? file_fdatawait_range+0x20/0x20 [Tue Aug 25 16:41:16 2020] __filemap_fdatawait_range+0x89/0xf0 [Tue Aug 25 16:41:16 2020] filemap_fdatawait_range+0xe/0x20 [Tue Aug 25 16:41:16 2020] __btrfs_wait_marked_extents.isra.19+0xc2/0x100 [btrfs] [Tue Aug 25 16:41:16 2020] btrfs_write_and_wait_transaction.isra.23+0x67/0xd0 [btrfs] [Tue Aug 25 16:41:16 2020] btrfs_commit_transaction+0x755/0xa50 [btrfs] [Tue Aug 25 16:41:16 2020] ? start_transaction+0xd5/0x540 [btrfs] [Tue Aug 25 16:41:16 2020] transaction_kthread+0x144/0x170 [btrfs] [Tue Aug 25 16:41:16 2020] ? btrfs_cleanup_transaction+0x590/0x590 [btrfs] [Tue Aug 25 16:41:16 2020] kthread+0x112/0x130 [Tue Aug 25 16:41:16 2020] ? kthread_park+0x80/0x80 [Tue Aug 25 16:41:16 2020] ret_from_fork+0x22/0x40 [Tue Aug 25 16:41:16 2020] btrfs D 0 30168 30162 0x00000000 [Tue Aug 25 16:41:16 2020] Call Trace: [Tue Aug 25 16:41:16 2020] __schedule+0x2dd/0x710 [Tue Aug 25 16:41:16 2020] schedule+0x40/0xb0 [Tue Aug 25 16:41:16 2020] wait_for_commit+0x58/0x80 [btrfs] [Tue Aug 25 16:41:16 2020] ? finish_wait+0x80/0x80 [Tue Aug 25 16:41:16 2020] btrfs_commit_transaction+0x169/0xa50 [btrfs] [Tue Aug 25 16:41:16 2020] ? btrfs_record_root_in_trans+0x56/0x60 [btrfs] [Tue Aug 25 16:41:16 2020] ? start_transaction+0xd5/0x540 [btrfs] [Tue Aug 25 16:41:16 2020] btrfs_mksubvol+0x2e9/0x450 [btrfs] [Tue Aug 25 16:41:16 2020] __btrfs_ioctl_snap_create+0x167/0x170 [btrfs] [Tue Aug 25 16:41:16 2020] btrfs_ioctl_snap_create_v2+0xc5/0xe0 [btrfs] [Tue Aug 25 16:41:16 2020] btrfs_ioctl+0xf61/0x2ef0 [btrfs] [Tue Aug 25 16:41:16 2020] ? ksys_ioctl+0x86/0xc0 [Tue Aug 25 16:41:16 2020] ksys_ioctl+0x86/0xc0 [Tue Aug 25 16:41:16 2020] __x64_sys_ioctl+0x16/0x20 [Tue Aug 25 16:41:16 2020] do_syscall_64+0x52/0x170 [Tue Aug 25 16:41:16 2020] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [Tue Aug 25 16:41:16 2020] RIP: 0033:0x7f273259b427 [Tue Aug 25 16:41:16 2020] Code: Bad RIP value. [Tue Aug 25 16:41:16 2020] RSP: 002b:00007ffe48178418 EFLAGS: 00000206 ORIG_RAX: 0000000000000010 [Tue Aug 25 16:41:16 2020] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f273259b427 [Tue Aug 25 16:41:16 2020] RDX: 00007ffe48178458 RSI: 0000000050009417 RDI: 0000000000000003 [Tue Aug 25 16:41:16 2020] RBP: 00005637741dc260 R08: 0000000000000008 R09: 0000000035322d38 [Tue Aug 25 16:41:16 2020] R10: fffffffffffffb66 R11: 0000000000000206 R12: 00005637741dc2b0 [Tue Aug 25 16:41:16 2020] R13: 00005637741dc2b0 R14: 0000000000000003 R15: 0000000000000004 [Tue Aug 25 16:41:16 2020] btrfs D 0 31094 31088 0x00000000 [Tue Aug 25 16:41:16 2020] Call Trace: [Tue Aug 25 16:41:16 2020] __schedule+0x2dd/0x710 [Tue Aug 25 16:41:16 2020] schedule+0x40/0xb0 [Tue Aug 25 16:41:16 2020] rwsem_down_write_slowpath+0x329/0x4e0 [Tue Aug 25 16:41:16 2020] ? kmem_cache_alloc_trace+0x15e/0x230 [Tue Aug 25 16:41:16 2020] btrfs_delete_subvolume+0x90/0x5f0 [btrfs] [Tue Aug 25 16:41:16 2020] ? d_lookup+0x25/0x50 [Tue Aug 25 16:41:16 2020] btrfs_ioctl_snap_destroy+0x5b3/0x6f0 [btrfs] [Tue Aug 25 16:41:16 2020] btrfs_ioctl+0xa5f/0x2ef0 [btrfs] [Tue Aug 25 16:41:16 2020] ? ksys_ioctl+0x86/0xc0 [Tue Aug 25 16:41:16 2020] ksys_ioctl+0x86/0xc0 [Tue Aug 25 16:41:16 2020] __x64_sys_ioctl+0x16/0x20 [Tue Aug 25 16:41:16 2020] do_syscall_64+0x52/0x170 [Tue Aug 25 16:41:16 2020] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [Tue Aug 25 16:41:16 2020] RIP: 0033:0x7ff3fa6a3427 [Tue Aug 25 16:41:16 2020] Code: Bad RIP value. [Tue Aug 25 16:41:16 2020] RSP: 002b:00007ffe92fc4058 EFLAGS: 00000202 ORIG_RAX: 0000000000000010 [Tue Aug 25 16:41:16 2020] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007ff3fa6a3427 [Tue Aug 25 16:41:16 2020] RDX: 00007ffe92fc4090 RSI: 000000005000940f RDI: 0000000000000003 [Tue Aug 25 16:41:16 2020] RBP: 0000000000000000 R08: 000055b4e34ab2ca R09: 00007ff3fa72de80 [Tue Aug 25 16:41:16 2020] R10: fffffffffffffb66 R11: 0000000000000202 R12: 0000000000000003 [Tue Aug 25 16:41:16 2020] R13: 0000000000000003 R14: 00007ffe92fc4090 R15: 000055b4e34ab2ca [Tue Aug 25 16:41:16 2020] btrfs D 0 31357 31351 0x00000000 [Tue Aug 25 16:41:16 2020] Call Trace: [Tue Aug 25 16:41:16 2020] __schedule+0x2dd/0x710 [Tue Aug 25 16:41:16 2020] schedule+0x40/0xb0 [Tue Aug 25 16:41:16 2020] rwsem_down_write_slowpath+0x329/0x4e0 [Tue Aug 25 16:41:16 2020] ? kmem_cache_alloc_trace+0x15e/0x230 [Tue Aug 25 16:41:16 2020] btrfs_delete_subvolume+0x90/0x5f0 [btrfs] [Tue Aug 25 16:41:16 2020] ? d_lookup+0x25/0x50 [Tue Aug 25 16:41:16 2020] btrfs_ioctl_snap_destroy+0x5b3/0x6f0 [btrfs] [Tue Aug 25 16:41:16 2020] btrfs_ioctl+0xa5f/0x2ef0 [btrfs] [Tue Aug 25 16:41:16 2020] ? ksys_ioctl+0x86/0xc0 [Tue Aug 25 16:41:16 2020] ksys_ioctl+0x86/0xc0 [Tue Aug 25 16:41:16 2020] __x64_sys_ioctl+0x16/0x20 [Tue Aug 25 16:41:16 2020] do_syscall_64+0x52/0x170 [Tue Aug 25 16:41:16 2020] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [Tue Aug 25 16:41:16 2020] RIP: 0033:0x7f9c14290427 [Tue Aug 25 16:41:16 2020] Code: Bad RIP value. [Tue Aug 25 16:41:16 2020] RSP: 002b:00007fff4c9f8ed8 EFLAGS: 00000206 ORIG_RAX: 0000000000000010 [Tue Aug 25 16:41:16 2020] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f9c14290427 [Tue Aug 25 16:41:16 2020] RDX: 00007fff4c9f8f10 RSI: 000000005000940f RDI: 0000000000000003 [Tue Aug 25 16:41:16 2020] RBP: 0000000000000000 R08: 000055ea83aa82c8 R09: 00007f9c1431ae80 [Tue Aug 25 16:41:16 2020] R10: fffffffffffffb66 R11: 0000000000000206 R12: 0000000000000003 [Tue Aug 25 16:41:16 2020] R13: 0000000000000003 R14: 00007fff4c9f8f10 R15: 000055ea83aa82c8 [Tue Aug 25 16:41:16 2020] btrfs D 0 32277 32271 0x00000000 [Tue Aug 25 16:41:16 2020] Call Trace: [Tue Aug 25 16:41:16 2020] __schedule+0x2dd/0x710 [Tue Aug 25 16:41:16 2020] schedule+0x40/0xb0 [Tue Aug 25 16:41:16 2020] rwsem_down_write_slowpath+0x329/0x4e0 [Tue Aug 25 16:41:16 2020] ? kmem_cache_alloc_trace+0x15e/0x230 [Tue Aug 25 16:41:16 2020] btrfs_delete_subvolume+0x90/0x5f0 [btrfs] [Tue Aug 25 16:41:16 2020] ? d_lookup+0x25/0x50 [Tue Aug 25 16:41:16 2020] btrfs_ioctl_snap_destroy+0x5b3/0x6f0 [btrfs] [Tue Aug 25 16:41:16 2020] btrfs_ioctl+0xa5f/0x2ef0 [btrfs] [Tue Aug 25 16:41:16 2020] ? ksys_ioctl+0x86/0xc0 [Tue Aug 25 16:41:16 2020] ksys_ioctl+0x86/0xc0 [Tue Aug 25 16:41:16 2020] __x64_sys_ioctl+0x16/0x20 [Tue Aug 25 16:41:16 2020] do_syscall_64+0x52/0x170 [Tue Aug 25 16:41:16 2020] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [Tue Aug 25 16:41:16 2020] RIP: 0033:0x7f0b35736427 [Tue Aug 25 16:41:16 2020] Code: Bad RIP value. [Tue Aug 25 16:41:16 2020] RSP: 002b:00007fff96ad7c48 EFLAGS: 00000206 ORIG_RAX: 0000000000000010 [Tue Aug 25 16:41:16 2020] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f0b35736427 [Tue Aug 25 16:41:16 2020] RDX: 00007fff96ad7c80 RSI: 000000005000940f RDI: 0000000000000003 [Tue Aug 25 16:41:16 2020] RBP: 0000000000000000 R08: 000055e2598b62c8 R09: 00007f0b357c0e80 [Tue Aug 25 16:41:16 2020] R10: fffffffffffffb66 R11: 0000000000000206 R12: 0000000000000003 [Tue Aug 25 16:41:16 2020] R13: 0000000000000003 R14: 00007fff96ad7c80 R15: 000055e2598b62c8 [Tue Aug 25 16:41:16 2020] btrfs D 0 32451 32445 0x00000000 [Tue Aug 25 16:41:16 2020] Call Trace: [Tue Aug 25 16:41:16 2020] __schedule+0x2dd/0x710 [Tue Aug 25 16:41:16 2020] schedule+0x40/0xb0 [Tue Aug 25 16:41:16 2020] rwsem_down_write_slowpath+0x329/0x4e0 [Tue Aug 25 16:41:16 2020] ? kmem_cache_alloc_trace+0x15e/0x230 [Tue Aug 25 16:41:16 2020] btrfs_delete_subvolume+0x90/0x5f0 [btrfs] [Tue Aug 25 16:41:16 2020] ? d_lookup+0x25/0x50 [Tue Aug 25 16:41:16 2020] btrfs_ioctl_snap_destroy+0x5b3/0x6f0 [btrfs] [Tue Aug 25 16:41:16 2020] btrfs_ioctl+0xa5f/0x2ef0 [btrfs] [Tue Aug 25 16:41:16 2020] ? ksys_ioctl+0x86/0xc0 [Tue Aug 25 16:41:16 2020] ksys_ioctl+0x86/0xc0 [Tue Aug 25 16:41:16 2020] __x64_sys_ioctl+0x16/0x20 [Tue Aug 25 16:41:16 2020] do_syscall_64+0x52/0x170 [Tue Aug 25 16:41:16 2020] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [Tue Aug 25 16:41:16 2020] RIP: 0033:0x7f0517ff8427 [Tue Aug 25 16:41:16 2020] Code: Bad RIP value. [Tue Aug 25 16:41:16 2020] RSP: 002b:00007ffc862d3c98 EFLAGS: 00000202 ORIG_RAX: 0000000000000010 [Tue Aug 25 16:41:16 2020] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f0517ff8427 [Tue Aug 25 16:41:16 2020] RDX: 00007ffc862d3cd0 RSI: 000000005000940f RDI: 0000000000000003 [Tue Aug 25 16:41:16 2020] RBP: 0000000000000000 R08: 0000555d6d7872ca R09: 00007f0518082e80 [Tue Aug 25 16:41:16 2020] R10: fffffffffffffb66 R11: 0000000000000202 R12: 0000000000000003 [Tue Aug 25 16:41:16 2020] R13: 0000000000000003 R14: 00007ffc862d3cd0 R15: 0000555d6d7872ca [Tue Aug 25 16:41:16 2020] btrfs D 0 596 590 0x00000000 [Tue Aug 25 16:41:16 2020] Call Trace: [Tue Aug 25 16:41:16 2020] __schedule+0x2dd/0x710 [Tue Aug 25 16:41:16 2020] schedule+0x40/0xb0 [Tue Aug 25 16:41:16 2020] rwsem_down_write_slowpath+0x329/0x4e0 [Tue Aug 25 16:41:16 2020] ? kmem_cache_alloc_trace+0x15e/0x230 [Tue Aug 25 16:41:16 2020] btrfs_delete_subvolume+0x90/0x5f0 [btrfs] [Tue Aug 25 16:41:16 2020] ? d_lookup+0x25/0x50 [Tue Aug 25 16:41:16 2020] btrfs_ioctl_snap_destroy+0x5b3/0x6f0 [btrfs] [Tue Aug 25 16:41:16 2020] btrfs_ioctl+0xa5f/0x2ef0 [btrfs] [Tue Aug 25 16:41:16 2020] ? ksys_ioctl+0x86/0xc0 [Tue Aug 25 16:41:16 2020] ksys_ioctl+0x86/0xc0 [Tue Aug 25 16:41:16 2020] __x64_sys_ioctl+0x16/0x20 [Tue Aug 25 16:41:16 2020] do_syscall_64+0x52/0x170 [Tue Aug 25 16:41:16 2020] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [Tue Aug 25 16:41:16 2020] RIP: 0033:0x7ffa2b954427 [Tue Aug 25 16:41:16 2020] Code: Bad RIP value. [Tue Aug 25 16:41:16 2020] RSP: 002b:00007ffc88d95748 EFLAGS: 00000206 ORIG_RAX: 0000000000000010 [Tue Aug 25 16:41:16 2020] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007ffa2b954427 [Tue Aug 25 16:41:16 2020] RDX: 00007ffc88d95780 RSI: 000000005000940f RDI: 0000000000000003 [Tue Aug 25 16:41:16 2020] RBP: 0000000000000000 R08: 0000558d2b97f2c8 R09: 00007ffa2b9dee80 [Tue Aug 25 16:41:16 2020] R10: fffffffffffffb66 R11: 0000000000000206 R12: 0000000000000003 [Tue Aug 25 16:41:16 2020] R13: 0000000000000003 R14: 00007ffc88d95780 R15: 0000558d2b97f2c8 [Tue Aug 25 16:41:16 2020] btrfs D 0 792 786 0x00000000 [Tue Aug 25 16:41:16 2020] Call Trace: [Tue Aug 25 16:41:16 2020] __schedule+0x2dd/0x710 [Tue Aug 25 16:41:16 2020] schedule+0x40/0xb0 [Tue Aug 25 16:41:16 2020] rwsem_down_write_slowpath+0x329/0x4e0 [Tue Aug 25 16:41:16 2020] ? kmem_cache_alloc_trace+0x15e/0x230 [Tue Aug 25 16:41:16 2020] btrfs_delete_subvolume+0x90/0x5f0 [btrfs] [Tue Aug 25 16:41:16 2020] ? d_lookup+0x25/0x50 [Tue Aug 25 16:41:16 2020] btrfs_ioctl_snap_destroy+0x5b3/0x6f0 [btrfs] [Tue Aug 25 16:41:16 2020] btrfs_ioctl+0xa5f/0x2ef0 [btrfs] [Tue Aug 25 16:41:16 2020] ? ksys_ioctl+0x86/0xc0 [Tue Aug 25 16:41:16 2020] ksys_ioctl+0x86/0xc0 [Tue Aug 25 16:41:16 2020] __x64_sys_ioctl+0x16/0x20 [Tue Aug 25 16:41:16 2020] do_syscall_64+0x52/0x170 [Tue Aug 25 16:41:16 2020] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [Tue Aug 25 16:41:16 2020] RIP: 0033:0x7f74f06d2427 [Tue Aug 25 16:41:16 2020] Code: Bad RIP value. [Tue Aug 25 16:41:16 2020] RSP: 002b:00007fffbb878738 EFLAGS: 00000202 ORIG_RAX: 0000000000000010 [Tue Aug 25 16:41:16 2020] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f74f06d2427 [Tue Aug 25 16:41:16 2020] RDX: 00007fffbb878770 RSI: 000000005000940f RDI: 0000000000000003 [Tue Aug 25 16:41:16 2020] RBP: 0000000000000000 R08: 000055f062e442c7 R09: 00007f74f075ce80 [Tue Aug 25 16:41:16 2020] R10: fffffffffffffb66 R11: 0000000000000202 R12: 0000000000000003 [Tue Aug 25 16:41:16 2020] R13: 0000000000000003 R14: 00007fffbb878770 R15: 000055f062e442c7 [Tue Aug 25 16:41:16 2020] btrfs D 0 833 827 0x00000000 [Tue Aug 25 16:41:16 2020] Call Trace: [Tue Aug 25 16:41:16 2020] __schedule+0x2dd/0x710 [Tue Aug 25 16:41:16 2020] schedule+0x40/0xb0 [Tue Aug 25 16:41:16 2020] rwsem_down_write_slowpath+0x329/0x4e0 [Tue Aug 25 16:41:16 2020] ? kmem_cache_alloc_trace+0x15e/0x230 [Tue Aug 25 16:41:16 2020] btrfs_delete_subvolume+0x90/0x5f0 [btrfs] [Tue Aug 25 16:41:16 2020] ? d_lookup+0x25/0x50 [Tue Aug 25 16:41:16 2020] btrfs_ioctl_snap_destroy+0x5b3/0x6f0 [btrfs] [Tue Aug 25 16:41:16 2020] btrfs_ioctl+0xa5f/0x2ef0 [btrfs] [Tue Aug 25 16:41:16 2020] ? ksys_ioctl+0x86/0xc0 [Tue Aug 25 16:41:16 2020] ksys_ioctl+0x86/0xc0 [Tue Aug 25 16:41:16 2020] __x64_sys_ioctl+0x16/0x20 [Tue Aug 25 16:41:16 2020] do_syscall_64+0x52/0x170 [Tue Aug 25 16:41:16 2020] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [Tue Aug 25 16:41:16 2020] RIP: 0033:0x7f65fee13427 [Tue Aug 25 16:41:16 2020] Code: Bad RIP value. [Tue Aug 25 16:41:16 2020] RSP: 002b:00007ffc45aa0508 EFLAGS: 00000202 ORIG_RAX: 0000000000000010 [Tue Aug 25 16:41:16 2020] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f65fee13427 [Tue Aug 25 16:41:16 2020] RDX: 00007ffc45aa0540 RSI: 000000005000940f RDI: 0000000000000003 [Tue Aug 25 16:41:16 2020] RBP: 0000000000000000 R08: 000055d819de32c6 R09: 00007f65fee9de80 [Tue Aug 25 16:41:16 2020] R10: fffffffffffffb66 R11: 0000000000000202 R12: 0000000000000003 [Tue Aug 25 16:41:16 2020] R13: 0000000000000003 R14: 00007ffc45aa0540 R15: 000055d819de32c6 [Tue Aug 25 16:41:16 2020] btrfs D 0 10542 10515 0x00000000 [Tue Aug 25 16:41:16 2020] Call Trace: [Tue Aug 25 16:41:16 2020] __schedule+0x2dd/0x710 [Tue Aug 25 16:41:16 2020] schedule+0x40/0xb0 [Tue Aug 25 16:41:16 2020] rwsem_down_write_slowpath+0x329/0x4e0 [Tue Aug 25 16:41:16 2020] ? kmem_cache_alloc_trace+0x15e/0x230 [Tue Aug 25 16:41:16 2020] btrfs_delete_subvolume+0x90/0x5f0 [btrfs] [Tue Aug 25 16:41:16 2020] ? d_lookup+0x25/0x50 [Tue Aug 25 16:41:16 2020] btrfs_ioctl_snap_destroy+0x5b3/0x6f0 [btrfs] [Tue Aug 25 16:41:16 2020] btrfs_ioctl+0xa5f/0x2ef0 [btrfs] [Tue Aug 25 16:41:16 2020] ? ksys_ioctl+0x86/0xc0 [Tue Aug 25 16:41:16 2020] ksys_ioctl+0x86/0xc0 [Tue Aug 25 16:41:16 2020] __x64_sys_ioctl+0x16/0x20 [Tue Aug 25 16:41:16 2020] do_syscall_64+0x52/0x170 [Tue Aug 25 16:41:16 2020] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [Tue Aug 25 16:41:16 2020] RIP: 0033:0x7f48b0d4a427 [Tue Aug 25 16:41:16 2020] Code: Bad RIP value. [Tue Aug 25 16:41:16 2020] RSP: 002b:00007ffdf1ab4fd8 EFLAGS: 00000206 ORIG_RAX: 0000000000000010 [Tue Aug 25 16:41:16 2020] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f48b0d4a427 [Tue Aug 25 16:41:16 2020] RDX: 00007ffdf1ab5010 RSI: 000000005000940f RDI: 0000000000000003 [Tue Aug 25 16:41:16 2020] RBP: 0000000000000000 R08: 00005631cce8a2c8 R09: 00007f48b0dd4e80 [Tue Aug 25 16:41:16 2020] R10: fffffffffffffb66 R11: 0000000000000206 R12: 0000000000000003 [Tue Aug 25 16:41:16 2020] R13: 0000000000000003 R14: 00007ffdf1ab5010 R15: 00005631cce8a2c8 [Tue Aug 25 16:41:16 2020] btrfs D 0 1667 1661 0x00000000 [Tue Aug 25 16:41:16 2020] Call Trace: [Tue Aug 25 16:41:16 2020] __schedule+0x2dd/0x710 [Tue Aug 25 16:41:16 2020] schedule+0x40/0xb0 [Tue Aug 25 16:41:16 2020] rwsem_down_write_slowpath+0x329/0x4e0 [Tue Aug 25 16:41:16 2020] ? kmem_cache_alloc_trace+0x15e/0x230 [Tue Aug 25 16:41:16 2020] btrfs_delete_subvolume+0x90/0x5f0 [btrfs] [Tue Aug 25 16:41:16 2020] ? d_lookup+0x25/0x50 [Tue Aug 25 16:41:16 2020] btrfs_ioctl_snap_destroy+0x5b3/0x6f0 [btrfs] [Tue Aug 25 16:41:16 2020] btrfs_ioctl+0xa5f/0x2ef0 [btrfs] [Tue Aug 25 16:41:16 2020] ? ksys_ioctl+0x86/0xc0 [Tue Aug 25 16:41:16 2020] ksys_ioctl+0x86/0xc0 [Tue Aug 25 16:41:16 2020] __x64_sys_ioctl+0x16/0x20 [Tue Aug 25 16:41:16 2020] do_syscall_64+0x52/0x170 [Tue Aug 25 16:41:16 2020] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [Tue Aug 25 16:41:16 2020] RIP: 0033:0x7f759eff1427 [Tue Aug 25 16:41:16 2020] Code: Bad RIP value. [Tue Aug 25 16:41:16 2020] RSP: 002b:00007ffcc4fb06c8 EFLAGS: 00000202 ORIG_RAX: 0000000000000010 [Tue Aug 25 16:41:16 2020] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f759eff1427 [Tue Aug 25 16:41:16 2020] RDX: 00007ffcc4fb0700 RSI: 000000005000940f RDI: 0000000000000003 [Tue Aug 25 16:41:16 2020] RBP: 0000000000000000 R08: 00005584f7c5a2ca R09: 00007f759f07be80 [Tue Aug 25 16:41:16 2020] R10: fffffffffffffb66 R11: 0000000000000202 R12: 0000000000000003 [Tue Aug 25 16:41:16 2020] R13: 0000000000000003 R14: 00007ffcc4fb0700 R15: 00005584f7c5a2ca [Tue Aug 25 16:41:16 2020] btrfs D 0 2473 2467 0x00000000 [Tue Aug 25 16:41:16 2020] Call Trace: [Tue Aug 25 16:41:16 2020] __schedule+0x2dd/0x710 [Tue Aug 25 16:41:16 2020] schedule+0x40/0xb0 [Tue Aug 25 16:41:16 2020] rwsem_down_write_slowpath+0x329/0x4e0 [Tue Aug 25 16:41:16 2020] ? kmem_cache_alloc_trace+0x15e/0x230 [Tue Aug 25 16:41:16 2020] btrfs_delete_subvolume+0x90/0x5f0 [btrfs] [Tue Aug 25 16:41:16 2020] ? d_lookup+0x25/0x50 [Tue Aug 25 16:41:16 2020] btrfs_ioctl_snap_destroy+0x5b3/0x6f0 [btrfs] [Tue Aug 25 16:41:16 2020] btrfs_ioctl+0xa5f/0x2ef0 [btrfs] [Tue Aug 25 16:41:16 2020] ? ksys_ioctl+0x86/0xc0 [Tue Aug 25 16:41:16 2020] ksys_ioctl+0x86/0xc0 [Tue Aug 25 16:41:16 2020] __x64_sys_ioctl+0x16/0x20 [Tue Aug 25 16:41:16 2020] do_syscall_64+0x52/0x170 [Tue Aug 25 16:41:16 2020] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [Tue Aug 25 16:41:16 2020] RIP: 0033:0x7f278ea1a427 [Tue Aug 25 16:41:16 2020] Code: Bad RIP value. [Tue Aug 25 16:41:16 2020] RSP: 002b:00007ffd784d5318 EFLAGS: 00000206 ORIG_RAX: 0000000000000010 [Tue Aug 25 16:41:16 2020] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f278ea1a427 [Tue Aug 25 16:41:16 2020] RDX: 00007ffd784d5350 RSI: 000000005000940f RDI: 0000000000000003 [Tue Aug 25 16:41:16 2020] RBP: 0000000000000000 R08: 000055b8f4d412de R09: 00007f278eaa4e80 [Tue Aug 25 16:41:16 2020] R10: fffffffffffffb66 R11: 0000000000000206 R12: 0000000000000003 [Tue Aug 25 16:41:16 2020] R13: 0000000000000003 R14: 00007ffd784d5350 R15: 000055b8f4d412de