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

From: syzbot
Date: Fri May 31 2024 - 09:49:40 EST

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@xxxxxxxxxxxxxxxxxxxxxxxxx

------------[ 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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