[syzbot] [block?] WARNING: locking bug in mempool_alloc_noprof

[syzbot <syzbot+c8ae2cacba71e6145314@syzkaller.appspotmail.com>]

Hello,

syzbot found the following issue on:

HEAD commit:    4a4be1ad3a6e Revert "vfs: Delete the associated dentry whe..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=12765f72980000
kernel config:  https://syzkaller.appspot.com/x/.config?x=733cc7a95171d8e7
dashboard link: https://syzkaller.appspot.com/bug?extid=c8ae2cacba71e6145314
compiler:       gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
userspace arch: i386

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/7bc7510fe41f/non_bootable_disk-4a4be1ad.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/a9bbdc63efe9/vmlinux-4a4be1ad.xz
kernel image: https://storage.googleapis.com/syzbot-assets/ed08b308e5d6/bzImage-4a4be1ad.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+c8ae2cacba71e6145314@syzkaller.appspotmail.com

------------[ cut here ]------------
Looking for class "c->lock" with key __key.0, but found a different class "&c->lock" with the same key
WARNING: CPU: 1 PID: 6462 at kernel/locking/lockdep.c:932 look_up_lock_class+0x133/0x140 kernel/locking/lockdep.c:932
Modules linked in:
CPU: 1 PID: 6462 Comm: syz-executor.2 Not tainted 6.10.0-rc1-syzkaller-00027-g4a4be1ad3a6e #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
RIP: 0010:look_up_lock_class+0x133/0x140 kernel/locking/lockdep.c:932
Code: c7 c7 a0 b7 2c 8b e8 ec a3 74 f6 90 0f 0b 90 90 90 31 db eb be c6 05 74 d6 ef 04 01 90 48 c7 c7 c0 ba 2c 8b e8 ce a3 74 f6 90 <0f> 0b 90 90 e9 62 ff ff ff 0f 1f 40 00 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffc90002f6edc8 EFLAGS: 00010086
RAX: 0000000000000000 RBX: ffffffff941f9940 RCX: ffffc9000cb53000
RDX: 0000000000040000 RSI: ffffffff81510236 RDI: 0000000000000001
RBP: ffffffff94aedd50 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 000000006b6f6f4c R12: ffffe8ffad169870
R13: 0000000000000000 R14: 0000000000000000 R15: ffffffff94ad5be0
FS:  0000000000000000(0000) GS:ffff88802c100000(0063) knlGS:00000000f5effb40
CS:  0010 DS: 002b ES: 002b CR0: 0000000080050033
CR2: 0000000020002000 CR3: 000000005f492000 CR4: 0000000000352ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 register_lock_class+0xb1/0x1230 kernel/locking/lockdep.c:1284
 __lock_acquire+0x111/0x3b30 kernel/locking/lockdep.c:5014
 lock_acquire kernel/locking/lockdep.c:5754 [inline]
 lock_acquire+0x1b1/0x560 kernel/locking/lockdep.c:5719
 local_lock_acquire include/linux/local_lock_internal.h:29 [inline]
 ___slab_alloc+0x7bb/0x1870 mm/slub.c:3715
 __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3756
 __slab_alloc_node mm/slub.c:3809 [inline]
 slab_alloc_node mm/slub.c:3988 [inline]
 kmem_cache_alloc_noprof+0x2ae/0x2f0 mm/slub.c:4007
 mempool_alloc_noprof+0x176/0x390 mm/mempool.c:402
 bio_alloc_bioset+0x480/0x8b0 block/bio.c:554
 bch2_writepage_io_alloc fs/bcachefs/fs-io-buffered.c:476 [inline]
 __bch2_writepage+0x107e/0x2500 fs/bcachefs/fs-io-buffered.c:610
 write_cache_pages+0xb0/0x130 mm/page-writeback.c:2591
 bch2_writepages+0x11f/0x200 fs/bcachefs/fs-io-buffered.c:650
 do_writepages+0x1a3/0x7f0 mm/page-writeback.c:2634
 filemap_fdatawrite_wbc mm/filemap.c:397 [inline]
 filemap_fdatawrite_wbc+0x148/0x1c0 mm/filemap.c:387
 __filemap_fdatawrite_range+0xba/0x100 mm/filemap.c:430
 file_write_and_wait_range+0xd0/0x140 mm/filemap.c:788
 bch2_fsync+0xa1/0x2c0 fs/bcachefs/fs-io.c:197
 vfs_fsync_range+0x141/0x230 fs/sync.c:188
 generic_write_sync include/linux/fs.h:2794 [inline]
 bch2_buffered_write fs/bcachefs/fs-io-buffered.c:1128 [inline]
 bch2_write_iter+0x756/0x3180 fs/bcachefs/fs-io-buffered.c:1136
 new_sync_write fs/read_write.c:497 [inline]
 vfs_write+0x6b6/0x1140 fs/read_write.c:590
 ksys_write+0x12f/0x260 fs/read_write.c:643
 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline]
 __do_fast_syscall_32+0x73/0x120 arch/x86/entry/common.c:386
 do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411
 entry_SYSENTER_compat_after_hwframe+0x84/0x8e
RIP: 0023:0xf730d579
Code: b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 00 00 00 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 8d b4 26 00 00 00 00 8d b4 26 00 00 00 00
RSP: 002b:00000000f5eff5ac EFLAGS: 00000292 ORIG_RAX: 0000000000000004
RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 0000000020000180
RDX: 0000000000002000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 </TASK>
----------------
Code disassembly (best guess), 2 bytes skipped:
   0:	10 06                	adc    %al,(%rsi)
   2:	03 74 b4 01          	add    0x1(%rsp,%rsi,4),%esi
   6:	10 07                	adc    %al,(%rdi)
   8:	03 74 b0 01          	add    0x1(%rax,%rsi,4),%esi
   c:	10 08                	adc    %cl,(%rax)
   e:	03 74 d8 01          	add    0x1(%rax,%rbx,8),%esi
  1e:	00 51 52             	add    %dl,0x52(%rcx)
  21:	55                   	push   %rbp
  22:	89 e5                	mov    %esp,%ebp
  24:	0f 34                	sysenter
  26:	cd 80                	int    $0x80
* 28:	5d                   	pop    %rbp <-- trapping instruction
  29:	5a                   	pop    %rdx
  2a:	59                   	pop    %rcx
  2b:	c3                   	ret
  2c:	90                   	nop
  2d:	90                   	nop
  2e:	90                   	nop
  2f:	90                   	nop
  30:	8d b4 26 00 00 00 00 	lea    0x0(%rsi,%riz,1),%esi
  37:	8d b4 26 00 00 00 00 	lea    0x0(%rsi,%riz,1),%esi


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