Re: generic/068 crash on 5.18-rc2?

Darrick J. Wong
2022-04-20T00:37:40Z

On Mon, Apr 18, 2022 at 10:47:47AM -0700, Darrick J. Wong wrote:
> On Wed, Apr 13, 2022 at 03:50:32PM +0100, Matthew Wilcox wrote:
> > On Tue, Apr 12, 2022 at 08:34:25PM -0700, Darrick J. Wong wrote:
> > > Hmm. Two nights in a row I've seen the following crash. Has anyone
> > > else seen this, or should I keep digging? This is a fairly boring
> > > x86_64 VM with a XFS v5 filesystem + rmapbt.
> >
> > I have not seen this before. I test with:
> > MKFS_OPTIONS -- -f -m reflink=1,rmapbt=1 -i sparse=1 -b size=1024 /dev/sdc
> >
> > Maybe I should try a 4096 byte block size.
> >
> > > mm/filemap.c:1653 is the BUG in:
> > >
> > > void folio_end_writeback(struct folio *folio)
> > > {
> > > /*
> > > * folio_test_clear_reclaim() could be used here but it is an
> > > * atomic operation and overkill in this particular case.
> > > * Failing to shuffle a folio marked for immediate reclaim is
> > > * too mild a gain to justify taking an atomic operation penalty
> > > * at the end of every folio writeback.
> > > */
> > > if (folio_test_reclaim(folio)) {
> > > folio_clear_reclaim(folio);
> > > folio_rotate_reclaimable(folio);
> > > }
> > >
> > > /*
> > > * Writeback does not hold a folio reference of its own, relying
> > > * on truncation to wait for the clearing of PG_writeback.
> > > * But here we must make sure that the folio is not freed and
> > > * reused before the folio_wake().
> > > */
> > > folio_get(folio);
> > > if (!__folio_end_writeback(folio))
> > > >>>> BUG();
> >
> > Grr, that should have been a VM_BUG_ON_FOLIO(1, folio) so we get useful
> > information about the folio (like whether it has an iop, or what order
> > the folio is). Can you make that change and try to reproduce?
>
> > What's going on here is that we've called folio_end_writeback() on a
> > folio which does not have the writeback flag set. That _should_ be
> > impossible, hence the use of BUG(). Either we've called
> > folio_end_writeback() twice on the same folio, or we neglected to set
> > the writeback flag on the folio. I don't immediately see why either
> > of those two things would happen.
>
> Well, I made that change and rebased to -rc3 to see if reverting that
> ZERO_PAGE thing would produce better results, I think I just got the
> same crash. Curiously, the only VM that died this time was the one
> running the realtime configuration, but it's still generic/068:
>
> FSTYP -- xfs (debug)
> PLATFORM -- Linux/x86_64 oci-mtr28 5.18.0-rc3-djwx #rc3 SMP PREEMPT_DYNAMIC Sun Apr 17 14:42:49 PDT 2022
> MKFS_OPTIONS -- -f -rrtdev=/dev/sdb4 -llogdev=/dev/sdb2 -m reflink=0,rmapbt=0, -d rtinherit=1, /dev/sda4
> MOUNT_OPTIONS -- -ortdev=/dev/sdb4 -ologdev=/dev/sdb2 /dev/sda4 /opt
>
> I don't know if it'll help, but here's the sequence of tests that we
> were running just prior to crashing:
>
> generic/445 3s
> generic/225 76s
> xfs/306 22s
> xfs/290 3s
> generic/155 [not run] Reflink not supported by test filesystem type: xfs
> generic/525 6s
> generic/269 89s
> generic/1206 [not run] xfs_io swapext -v vfs -s 64k -l 64k ioctl support is missing
> xfs/504 198s
> xfs/192 [not run] Reflink not supported by scratch filesystem type: xfs
> xfs/303 1s
> generic/346 6s
> generic/512 5s
> xfs/227 308s
> generic/147 [not run] Reflink not supported by test filesystem type: xfs
> generic/230 [not run] Quotas not supported on realtime test device
> generic/008 4s
> generic/108 4s
> xfs/264 12s
> generic/200 [not run] Reflink not supported by scratch filesystem type: xfs
> generic/493 [not run] Dedupe not supported by scratch filesystem type: xfs
> xfs/021 5s
> generic/672 [not run] Reflink not supported by scratch filesystem type: xfs
> xfs/493 5s
> xfs/146 13s
> xfs/315 [not run] Reflink not supported by scratch filesystem type: xfs
> generic/068
>
> And the dmesg output:
>
> run fstests generic/068 at 2022-04-17 16:57:16
> XFS (sda4): Mounting V5 Filesystem
> XFS (sda4): Ending clean mount
> page:ffffea0004a39c40 refcount:0 mapcount:0 mapping:0000000000000000 index:0x1 pfn:0x128e71
> flags: 0x17ff80000000000(node=0|zone=2|lastcpupid=0xfff)
> raw: 017ff80000000000 0000000000000000 ffffffff00000203 0000000000000000
> raw: 0000000000000001 0000000000000000 00000000ffffffff 0000000000000000
> page dumped because: VM_BUG_ON_FOLIO(((unsigned int) folio_ref_count(folio) + 127u <= 127u))
> ------------[ cut here ]------------
> kernel BUG at include/linux/mm.h:1164!
> invalid opcode: 0000 [#1] PREEMPT SMP
> CPU: 3 PID: 1094085 Comm: 3:0 Tainted: G W 5.18.0-rc3-djwx #rc3 0a707744ee7c555d54e50726c5b02515710a6aae
> Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS ?-20171121_152543-x86-ol7-builder-01.us.oracle.com-4.el7.1 04/01/2014
> Workqueue: xfs-conv/sda4 xfs_end_io [xfs]
> RIP: 0010:folio_end_writeback+0xd0/0x110
> Code: 80 60 02 fb 48 89 ef e8 5e 6d 01 00 8b 45 34 83 c0 7f 83 f8 7f 0f 87 6a ff ff ff 48 c7 c6 40 c7 e2 81 48 89 ef e8 30 69 04 00 <0f> 0b 48 89 ee e8 b6 51 02 00 eb 9a 48 c7 c6 c0 ad e5 81 48 89 ef
> RSP: 0018:ffffc900084f3d48 EFLAGS: 00010246
> RAX: 000000000000005c RBX: 0000000000001000 RCX: 0000000000000000
> RDX: 0000000000000000 RSI: ffffffff81e56da3 RDI: 00000000ffffffff
> RBP: ffffea0004a39c40 R08: 0000000000000000 R09: ffffffff8205fe40
> R10: 0000000000017578 R11: 00000000000175f0 R12: 0000000000004000
> R13: ffff88814dc5cd40 R14: 000000000000002e R15: ffffea0004a39c40
> FS: 0000000000000000(0000) GS:ffff88843fd80000(0000) knlGS:0000000000000000
> CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> CR2: 00007f2b0ea47010 CR3: 000000043f00c000 CR4: 00000000001506a0
> Call Trace:
> <TASK>
> iomap_finish_ioend+0x1ee/0x6a0
> iomap_finish_ioends+0x69/0x100
> xfs_end_ioend+0x5a/0x160 [xfs e8251de1111d7958449fd159d84af12a2afc12f2]
> xfs_end_io+0xb1/0xf0 [xfs e8251de1111d7958449fd159d84af12a2afc12f2]
> process_one_work+0x1df/0x3c0
> ? rescuer_thread+0x3b0/0x3b0
> worker_thread+0x53/0x3b0
> ? rescuer_thread+0x3b0/0x3b0
> kthread+0xea/0x110
> ? kthread_complete_and_exit+0x20/0x20
> ret_from_fork+0x1f/0x30
> </TASK>
> Modules linked in: xfs dm_zero btrfs blake2b_generic xor lzo_compress lzo_decompress zlib_deflate raid6_pq zstd_compress dm_delay dm_snapshot dm_thin_pool dm_persistent_data dm_bio_prison dm_bufio dm_flakey libcrc32c xt_REDIRECT iptable_nat nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 ip6t_REJECT nf_reject_ipv6 ipt_REJECT nf_reject_ipv4 auth_rpcgss oid_registry xt_tcpudp ip_set_hash_ip ip_set_hash_net xt_set ip_set_hash_mac ip_set nfnetlink ip6table_filter ip6_tables iptable_filter bfq sch_fq_codel ip_tables x_tables overlay nfsv4 af_packet [last unloaded: scsi_debug]
> Dumping ftrace buffer:
> (ftrace buffer empty)
> ---[ end trace 0000000000000000 ]---
> RIP: 0010:folio_end_writeback+0xd0/0x110
> Code: 80 60 02 fb 48 89 ef e8 5e 6d 01 00 8b 45 34 83 c0 7f 83 f8 7f 0f 87 6a ff ff ff 48 c7 c6 40 c7 e2 81 48 89 ef e8 30 69 04 00 <0f> 0b 48 89 ee e8 b6 51 02 00 eb 9a 48 c7 c6 c0 ad e5 81 48 89 ef
> RSP: 0018:ffffc900084f3d48 EFLAGS: 00010246
> RAX: 000000000000005c RBX: 0000000000001000 RCX: 0000000000000000
> RDX: 0000000000000000 RSI: ffffffff81e56da3 RDI: 00000000ffffffff
> RBP: ffffea0004a39c40 R08: 0000000000000000 R09: ffffffff8205fe40
> R10: 0000000000017578 R11: 00000000000175f0 R12: 0000000000004000
> R13: ffff88814dc5cd40 R14: 000000000000002e R15: ffffea0004a39c40
> FS: 0000000000000000(0000) GS:ffff88843fd80000(0000) knlGS:0000000000000000
> CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> CR2: 00007f2b0ea47010 CR3: 000000043f00c000 CR4: 00000000001506a0
>
> --D

Today I managed to capture stack traces of all the D state processes on
a system with the hang described above:

/proc/41/comm = khugepaged
/proc/41/stack : [<0>] flush_work+0x5c/0x80
[<0>] __lru_add_drain_all+0x134/0x1c0
[<0>] khugepaged+0x6c/0x2460
[<0>] kthread+0xea/0x110
[<0>] ret_from_fork+0x1f/0x30

Not sure if this is involved, but it might be?
These systems /do/ have KSM and HUGEPAGE_ALWAYS turned on.

/proc/411335/comm = u8:1+events_unbound
/proc/411335/stack : [<0>] __synchronize_srcu.part.0+0x86/0xf0
[<0>] fsnotify_mark_destroy_workfn+0x7c/0x110
[<0>] process_one_work+0x1df/0x3c0
[<0>] worker_thread+0x53/0x3b0
[<0>] kthread+0xea/0x110
[<0>] ret_from_fork+0x1f/0x30
/proc/973682/comm = u8:0+flush-8:0
/proc/973682/stack : [<0>] down+0x54/0x70
[<0>] xfs_buf_lock+0x2d/0xe0 [xfs]
[<0>] xfs_buf_find+0x356/0x880 [xfs]
[<0>] xfs_buf_get_map+0x46/0x3b0 [xfs]
[<0>] xfs_buf_read_map+0x52/0x2f0 [xfs]
[<0>] xfs_trans_read_buf_map+0x1bb/0x4a0 [xfs]
[<0>] xfs_btree_read_buf_block.constprop.0+0x96/0xd0 [xfs]
[<0>] xfs_btree_lookup_get_block+0x97/0x170 [xfs]
[<0>] xfs_btree_lookup+0xdd/0x540 [xfs]
[<0>] xfs_rmap_map+0xd0/0x860 [xfs]
[<0>] xfs_rmap_finish_one+0x243/0x300 [xfs]
[<0>] xfs_rmap_update_finish_item+0x37/0x70 [xfs]
[<0>] xfs_defer_finish_noroll+0x20a/0x6f0 [xfs]
[<0>] __xfs_trans_commit+0x153/0x3e0 [xfs]
[<0>] xfs_bmapi_convert_delalloc+0x495/0x5e0 [xfs]
[<0>] xfs_map_blocks+0x1ed/0x540 [xfs]
[<0>] iomap_do_writepage+0x2a3/0xae0
[<0>] write_cache_pages+0x224/0x6f0
[<0>] iomap_writepages+0x1c/0x40
[<0>] xfs_vm_writepages+0x7a/0xb0 [xfs]
[<0>] do_writepages+0xcc/0x1c0
[<0>] __writeback_single_inode+0x41/0x340
[<0>] writeback_sb_inodes+0x207/0x4a0
[<0>] __writeback_inodes_wb+0x4c/0xe0
[<0>] wb_writeback+0x1da/0x2c0
[<0>] wb_workfn+0x28c/0x500
[<0>] process_one_work+0x1df/0x3c0
[<0>] worker_thread+0x53/0x3b0
[<0>] kthread+0xea/0x110
[<0>] ret_from_fork+0x1f/0x30

Writeback is stuck in an rmapbt update...

/proc/1139791/comm = u8:2+events_unbound
/proc/1139791/stack : [<0>] __synchronize_srcu.part.0+0x86/0xf0
[<0>] fsnotify_connector_destroy_workfn+0x3c/0x60
[<0>] process_one_work+0x1df/0x3c0
[<0>] worker_thread+0x53/0x3b0
[<0>] kthread+0xea/0x110
[<0>] ret_from_fork+0x1f/0x30
/proc/1274752/comm = u8:3+xfs-blockgc/sda4
/proc/1274752/stack : [<0>] down+0x54/0x70
[<0>] xfs_buf_lock+0x2d/0xe0 [xfs]
[<0>] xfs_buf_find+0x356/0x880 [xfs]
[<0>] xfs_buf_get_map+0x46/0x3b0 [xfs]
[<0>] xfs_buf_read_map+0x52/0x2f0 [xfs]
[<0>] xfs_trans_read_buf_map+0x1bb/0x4a0 [xfs]
[<0>] xfs_read_agf+0xb2/0x1b0 [xfs]
[<0>] xfs_alloc_read_agf+0x54/0x370 [xfs]
[<0>] xfs_alloc_fix_freelist+0x38e/0x510 [xfs]
[<0>] xfs_free_extent_fix_freelist+0x61/0xa0 [xfs]
[<0>] xfs_rmap_finish_one+0xd9/0x300 [xfs]
[<0>] xfs_rmap_update_finish_item+0x37/0x70 [xfs]
[<0>] xfs_defer_finish_noroll+0x20a/0x6f0 [xfs]
[<0>] xfs_defer_finish+0x11/0xa0 [xfs]
[<0>] xfs_itruncate_extents_flags+0x14b/0x4b0 [xfs]
[<0>] xfs_free_eofblocks+0xe9/0x150 [xfs]
[<0>] xfs_icwalk_ag+0x4a7/0x800 [xfs]
[<0>] xfs_blockgc_worker+0x31/0x110 [xfs]
[<0>] process_one_work+0x1df/0x3c0
[<0>] worker_thread+0x53/0x3b0
[<0>] kthread+0xea/0x110
[<0>] ret_from_fork+0x1f/0x30

Stuck waiting for the AGF to do an rmapbt update...

/proc/1315282/comm = fstest
/proc/1315282/stack : [<0>] folio_wait_bit_common+0x148/0x460
[<0>] folio_wait_writeback+0x22/0x80
[<0>] truncate_inode_pages_range+0x3fe/0x6f0
[<0>] truncate_pagecache+0x44/0x60
[<0>] xfs_setattr_size+0x163/0x4d0 [xfs]
[<0>] xfs_vn_setattr+0x75/0x180 [xfs]
[<0>] notify_change+0x306/0x500
[<0>] do_truncate+0x7d/0xd0
[<0>] path_openat+0xc60/0x1060
[<0>] do_filp_open+0xa9/0x150
[<0>] do_sys_openat2+0x97/0x160
[<0>] __x64_sys_openat+0x54/0x90
[<0>] do_syscall_64+0x35/0x80
[<0>] entry_SYSCALL_64_after_hwframe+0x44/0xae
/proc/1315283/comm = fstest
/proc/1315283/stack : [<0>] folio_wait_bit_common+0x148/0x460
[<0>] folio_wait_writeback+0x22/0x80
[<0>] __filemap_fdatawait_range+0x8c/0x250
[<0>] filemap_write_and_wait_range+0x85/0xf0
[<0>] xfs_setattr_size+0x103/0x4d0 [xfs]
[<0>] xfs_vn_setattr+0x75/0x180 [xfs]
[<0>] notify_change+0x306/0x500
[<0>] do_truncate+0x7d/0xd0
[<0>] path_openat+0xc60/0x1060
[<0>] do_filp_open+0xa9/0x150
[<0>] do_sys_openat2+0x97/0x160
[<0>] __x64_sys_openat+0x54/0x90
[<0>] do_syscall_64+0x35/0x80
[<0>] entry_SYSCALL_64_after_hwframe+0x44/0xae
/proc/1315287/comm = fsstress
/proc/1315287/stack : [<0>] folio_wait_bit_common+0x148/0x460
[<0>] folio_wait_writeback+0x22/0x80
[<0>] __filemap_fdatawait_range+0x8c/0x250
[<0>] filemap_write_and_wait_range+0x85/0xf0
[<0>] xfs_setattr_size+0x2da/0x4d0 [xfs]
[<0>] xfs_vn_setattr+0x75/0x180 [xfs]
[<0>] notify_change+0x306/0x500
[<0>] do_truncate+0x7d/0xd0
[<0>] vfs_truncate+0x108/0x140
[<0>] do_sys_truncate.part.0+0x8a/0xa0
[<0>] do_syscall_64+0x35/0x80
[<0>] entry_SYSCALL_64_after_hwframe+0x44/0xae

Clearly stuck on writeback, not sure if it's the same file as the one
that tripped the assertion...

/proc/1315478/comm = u8:4+xfs-blockgc/sda4
/proc/1315478/stack : [<0>] down+0x54/0x70
[<0>] xfs_buf_lock+0x2d/0xe0 [xfs]
[<0>] xfs_buf_find+0x356/0x880 [xfs]
[<0>] xfs_buf_get_map+0x46/0x3b0 [xfs]
[<0>] xfs_buf_read_map+0x52/0x2f0 [xfs]
[<0>] xfs_trans_read_buf_map+0x1bb/0x4a0 [xfs]
[<0>] xfs_imap_to_bp+0x4e/0x70 [xfs]
[<0>] xfs_trans_log_inode+0x1da/0x350 [xfs]
[<0>] __xfs_bunmapi+0x7e8/0xd30 [xfs]
[<0>] xfs_itruncate_extents_flags+0x13d/0x4b0 [xfs]
[<0>] xfs_free_eofblocks+0xe9/0x150 [xfs]
[<0>] xfs_icwalk_ag+0x4a7/0x800 [xfs]
[<0>] xfs_blockgc_worker+0x31/0x110 [xfs]
[<0>] process_one_work+0x1df/0x3c0
[<0>] worker_thread+0x53/0x3b0
[<0>] kthread+0xea/0x110
[<0>] ret_from_fork+0x1f/0x30
/proc/1315479/comm = u8:5+xfs-blockgc/sda4
/proc/1315479/stack : [<0>] down+0x54/0x70
[<0>] xfs_buf_lock+0x2d/0xe0 [xfs]
[<0>] xfs_buf_find+0x356/0x880 [xfs]
[<0>] xfs_buf_get_map+0x46/0x3b0 [xfs]
[<0>] xfs_buf_read_map+0x52/0x2f0 [xfs]
[<0>] xfs_trans_read_buf_map+0x1bb/0x4a0 [xfs]
[<0>] xfs_imap_to_bp+0x4e/0x70 [xfs]
[<0>] xfs_trans_log_inode+0x1da/0x350 [xfs]
[<0>] __xfs_bunmapi+0x7e8/0xd30 [xfs]
[<0>] xfs_itruncate_extents_flags+0x13d/0x4b0 [xfs]
[<0>] xfs_free_eofblocks+0xe9/0x150 [xfs]
[<0>] xfs_icwalk_ag+0x4a7/0x800 [xfs]
[<0>] xfs_blockgc_worker+0x31/0x110 [xfs]
[<0>] process_one_work+0x1df/0x3c0
[<0>] worker_thread+0x53/0x3b0
[<0>] kthread+0xea/0x110
[<0>] ret_from_fork+0x1f/0x30

Both of these threads are stuck on the inode cluster buffer. If I had
to bet, I'd guess it's the one underlying the inode being processed by
pid 973682.

/proc/1315480/comm = u8:6+xfs-blockgc/sda4
/proc/1315480/stack : [<0>] down+0x54/0x70
[<0>] xfs_buf_lock+0x2d/0xe0 [xfs]
[<0>] xfs_buf_find+0x356/0x880 [xfs]
[<0>] xfs_buf_get_map+0x46/0x3b0 [xfs]
[<0>] xfs_buf_read_map+0x52/0x2f0 [xfs]
[<0>] xfs_trans_read_buf_map+0x1bb/0x4a0 [xfs]
[<0>] xfs_read_agf+0xb2/0x1b0 [xfs]
[<0>] xfs_alloc_read_agf+0x54/0x370 [xfs]
[<0>] xfs_alloc_fix_freelist+0x38e/0x510 [xfs]
[<0>] xfs_free_extent_fix_freelist+0x61/0xa0 [xfs]
[<0>] xfs_rmap_finish_one+0xd9/0x300 [xfs]
[<0>] xfs_rmap_update_finish_item+0x37/0x70 [xfs]
[<0>] xfs_defer_finish_noroll+0x20a/0x6f0 [xfs]
[<0>] xfs_defer_finish+0x11/0xa0 [xfs]
[<0>] xfs_itruncate_extents_flags+0x14b/0x4b0 [xfs]
[<0>] xfs_free_eofblocks+0xe9/0x150 [xfs]
[<0>] xfs_icwalk_ag+0x4a7/0x800 [xfs]
[<0>] xfs_blockgc_worker+0x31/0x110 [xfs]
[<0>] process_one_work+0x1df/0x3c0
[<0>] worker_thread+0x53/0x3b0
[<0>] kthread+0xea/0x110
[<0>] ret_from_fork+0x1f/0x30

Speculative preallocation garbage collection also got stuck waiting for
the AGF to do an rmapbt update.

--D

>
> >
> > >
> > >
> > > --D
> > >
> > > run fstests generic/068 at 2022-04-12 17:57:11
> > > XFS (sda3): Mounting V5 Filesystem
> > > XFS (sda3): Ending clean mount
> > > XFS (sda4): Mounting V5 Filesystem
> > > XFS (sda4): Ending clean mount
> > > ------------[ cut here ]------------
> > > kernel BUG at mm/filemap.c:1653!
> > > invalid opcode: 0000 [#1] PREEMPT SMP
> > > CPU: 0 PID: 1349866 Comm: 0:116 Tainted: G W 5.18.0-rc2-djwx #rc2 19cc48221d47ada6c8e5859639b6a0946c9a3777
> > > Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS ?-20171121_152543-x86-ol7-builder-01.us.oracle.com-4.el7.1 04/01/2014
> > > Workqueue: xfs-conv/sda4 xfs_end_io [xfs]
> > > RIP: 0010:folio_end_writeback+0x79/0x80
> > > Code: d2 75 1d f0 ff 4d 34 74 0e 5d c3 f0 80 67 02 fb e8 ac 29 01 00 eb ad 48 89 ef 5d e9 a1 0f 01 00 48 89 ee e8 b9 e8 01 00 eb d9 <0f> 0b 0f 1f 44 00 00 0f 1f 44 00 00 53 48 89 fb e8 62 f7 ff ff 48
> > > RSP: 0018:ffffc9000286fd50 EFLAGS: 00010246
> > > RAX: 0000000000000000 RBX: ffffea0007376840 RCX: 000000000000000c
> > > RDX: ffff88810d2de000 RSI: ffffffff81e55f0b RDI: ffff88810d2de000
> > > RBP: ffffea0007376840 R08: ffffea000b82c308 R09: ffffea000b82c308
> > > R10: 0000000000000001 R11: 000000000000000c R12: 0000000000000000
> > > R13: 000000000000c000 R14: 0000000000000005 R15: 0000000000000001
> > > FS: 0000000000000000(0000) GS:ffff88843fc00000(0000) knlGS:0000000000000000
> > > CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> > > CR2: 00007f5b067d0000 CR3: 000000010d1bb000 CR4: 00000000001506b0
> > > Call Trace:
> > > <TASK>
> > > iomap_finish_ioend+0x19e/0x560
> > > iomap_finish_ioends+0x69/0x100
> > > xfs_end_ioend+0x5a/0x160 [xfs 513857e2ae300a835ce1fbd8065a84dc5382e649]
> > > xfs_end_io+0xb1/0xf0 [xfs 513857e2ae300a835ce1fbd8065a84dc5382e649]
> > > process_one_work+0x1df/0x3c0
> > > ? rescuer_thread+0x3b0/0x3b0
> > > worker_thread+0x53/0x3b0
> > > ? rescuer_thread+0x3b0/0x3b0
> > > kthread+0xea/0x110
> > > ? kthread_complete_and_exit+0x20/0x20
> > > ret_from_fork+0x1f/0x30
> > > </TASK>
> > > Modules linked in: dm_snapshot dm_bufio dm_zero dm_flakey xfs libcrc32c xt_REDIRECT iptable_nat nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 ip6t_REJECT nf_reject_ipv6 ipt_REJECT nf_reject_ipv4 auth_rpcgss oid_registry xt_tcpudp ip_set_hash_ip ip_set_hash_net xt_set ip_set_hash_mac ip_set nfnetlink ip6table_filter ip6_tables iptable_filter bfq sch_fq_codel ip_tables x_tables overlay nfsv4 af_packet [last unloaded: scsi_debug]
> > > Dumping ftrace buffer:
> > > (ftrace buffer empty)
> > > ---[ end trace 0000000000000000 ]---
> > > RIP: 0010:folio_end_writeback+0x79/0x80
> > > Code: d2 75 1d f0 ff 4d 34 74 0e 5d c3 f0 80 67 02 fb e8 ac 29 01 00 eb ad 48 89 ef 5d e9 a1 0f 01 00 48 89 ee e8 b9 e8 01 00 eb d9 <0f> 0b 0f 1f 44 00 00 0f 1f 44 00 00 53 48 89 fb e8 62 f7 ff ff 48
> > > RSP: 0018:ffffc9000286fd50 EFLAGS: 00010246
> > > RAX: 0000000000000000 RBX: ffffea0007376840 RCX: 000000000000000c
> > > RDX: ffff88810d2de000 RSI: ffffffff81e55f0b RDI: ffff88810d2de000
> > > RBP: ffffea0007376840 R08: ffffea000b82c308 R09: ffffea000b82c308
> > > R10: 0000000000000001 R11: 000000000000000c R12: 0000000000000000
> > > R13: 000000000000c000 R14: 0000000000000005 R15: 0000000000000001
> > > FS: 0000000000000000(0000) GS:ffff88843fc00000(0000) knlGS:0000000000000000
> > > CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> > > CR2: 00007f4b94008278 CR3: 0000000101ac9000 CR4: 00000000001506b0
> > >