syzbot

syz-executor365[5076]: segfault at 0 ip 00007f312defdaf0 sp 00007fff45e3f308 error 4 in syz-executor3652527702[7f312de97000+88000] likely on CPU 1 (core 0, socket 0)
Code: 66 0f ef c0 66 0f ef c9 66 0f ef d2 66 0f ef db 48 89 f8 48 89 f9 48 81 e1 ff 0f 00 00 48 81 f9 cf 0f 00 00 77 74 48 83 e0 f0 <66> 0f 74 00 66 0f 74 48 10 66 0f 74 50 20 66 0f 74 58 30 66 0f d7
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WARNING: CPU: 0 PID: 5076 at include/linux/backing-dev.h:253 inode_to_wb include/linux/backing-dev.h:253 [inline]
WARNING: CPU: 0 PID: 5076 at include/linux/backing-dev.h:253 folio_account_dirtied mm/page-writeback.c:2656 [inline]
WARNING: CPU: 0 PID: 5076 at include/linux/backing-dev.h:253 __folio_mark_dirty+0xace/0xdf0 mm/page-writeback.c:2707
Modules linked in:
CPU: 0 PID: 5076 Comm: syz-executor365 Not tainted 6.3.0-rc2-syzkaller-00050-g9c1bec9c0b08 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/02/2023
RIP: 0010:inode_to_wb include/linux/backing-dev.h:253 [inline]
RIP: 0010:folio_account_dirtied mm/page-writeback.c:2656 [inline]
RIP: 0010:__folio_mark_dirty+0xace/0xdf0 mm/page-writeback.c:2707
Code: ff ff ff 48 8d 78 70 e8 f0 99 50 08 31 ff 89 c6 89 44 24 08 e8 33 a5 d1 ff 8b 44 24 08 85 c0 0f 85 bc f9 ff ff e8 d2 a8 d1 ff <0f> 0b e9 b0 f9 ff ff e8 c6 a8 d1 ff 0f 0b e9 d9 f5 ff ff 48 89 04
RSP: 0018:ffffc90003eaf818 EFLAGS: 00010093
RAX: 0000000000000000 RBX: ffff88801688f3d0 RCX: 0000000000000000
RDX: ffff8880232bba80 RSI: ffffffff81b13c2e RDI: 0000000000000005
RBP: ffffea0000631b40 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000293
R13: ffff88802af36258 R14: 0000000000000001 R15: 0000000000000001
FS:  0000000000000000(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000555b661ee000 CR3: 000000000c571000 CR4: 0000000000350ef0
Call Trace:
 <TASK>
 mark_buffer_dirty+0x31e/0x3e0 fs/buffer.c:1148
 gfs2_unpin+0x109/0xcf0 fs/gfs2/lops.c:111
 buf_lo_after_commit+0x144/0x210 fs/gfs2/lops.c:747
 lops_after_commit fs/gfs2/lops.h:49 [inline]
 gfs2_log_flush+0x140f/0x2900 fs/gfs2/log.c:1116
 gfs2_kill_sb+0x6a/0x430 fs/gfs2/ops_fstype.c:1789
 deactivate_locked_super+0x98/0x160 fs/super.c:331
 deactivate_super+0xb1/0xd0 fs/super.c:362
 cleanup_mnt+0x2ae/0x3d0 fs/namespace.c:1177
 task_work_run+0x16f/0x270 kernel/task_work.c:179
 exit_task_work include/linux/task_work.h:38 [inline]
 do_exit+0xad3/0x2960 kernel/exit.c:869
 do_group_exit+0xd4/0x2a0 kernel/exit.c:1019
 get_signal+0x2315/0x25b0 kernel/signal.c:2859
 arch_do_signal_or_restart+0x79/0x5c0 arch/x86/kernel/signal.c:306
 exit_to_user_mode_loop kernel/entry/common.c:168 [inline]
 exit_to_user_mode_prepare+0x15f/0x250 kernel/entry/common.c:203
 irqentry_exit_to_user_mode+0x9/0x40 kernel/entry/common.c:309
 exc_page_fault+0xc0/0x170 arch/x86/mm/fault.c:1557
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:570
RIP: 0033:0x7f312defdaf0
Code: Unable to access opcode bytes at 0x7f312defdac6.
RSP: 002b:00007fff45e3f308 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 00000000000000e0 RCX: 0000000000000000
RDX: 00000000000000e0 RSI: 00000000000000e0 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000000000c0 R11: 00000000000000e0 R12: 00000000ffffffff
R13: 00007fff45e3f3e0 R14: 0000000000000000 R15: 0000000000000000
 </TASK>
----------------
Code disassembly (best guess):
   0:	66 0f ef c0          	pxor   %xmm0,%xmm0
   4:	66 0f ef c9          	pxor   %xmm1,%xmm1
   8:	66 0f ef d2          	pxor   %xmm2,%xmm2
   c:	66 0f ef db          	pxor   %xmm3,%xmm3
  10:	48 89 f8             	mov    %rdi,%rax
  13:	48 89 f9             	mov    %rdi,%rcx
  16:	48 81 e1 ff 0f 00 00 	and    $0xfff,%rcx
  1d:	48 81 f9 cf 0f 00 00 	cmp    $0xfcf,%rcx
  24:	77 74                	ja     0x9a
  26:	48 83 e0 f0          	and    $0xfffffffffffffff0,%rax
* 2a:	66 0f 74 00          	pcmpeqb (%rax),%xmm0 <-- trapping instruction
  2e:	66 0f 74 48 10       	pcmpeqb 0x10(%rax),%xmm1
  33:	66 0f 74 50 20       	pcmpeqb 0x20(%rax),%xmm2
  38:	66 0f 74 58 30       	pcmpeqb 0x30(%rax),%xmm3
  3d:	66                   	data16
  3e:	0f                   	.byte 0xf
  3f:	d7                   	xlat   %ds:(%rbx)