[syzbot] [bcachefs?] WARNING in cleanup_srcu_struct (4)

From: syzbot
Date: Fri May 03 2024 - 10:35:50 EST


Hello,

syzbot found the following issue on:

HEAD commit: f03359bca01b Merge tag 'for-6.9-rc6-tag' of git://git.kern..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=14004498980000
kernel config: https://syzkaller.appspot.com/x/.config?x=3310e643b6ef5d69
dashboard link: https://syzkaller.appspot.com/bug?extid=6cf577c8ed4e23fe436b
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/1b4deeb2639b/disk-f03359bc.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/f3c3d98db8ef/vmlinux-f03359bc.xz
kernel image: https://storage.googleapis.com/syzbot-assets/6f79ee1ae20f/bzImage-f03359bc.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+6cf577c8ed4e23fe436b@xxxxxxxxxxxxxxxxxxxxxxxxx

------------[ cut here ]------------
WARNING: CPU: 1 PID: 32609 at kernel/rcu/srcutree.c:664 cleanup_srcu_struct+0x3d9/0x520 kernel/rcu/srcutree.c:664
Modules linked in:
CPU: 1 PID: 32609 Comm: syz-executor.1 Not tainted 6.9.0-rc6-syzkaller-00131-gf03359bca01b #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
RIP: 0010:cleanup_srcu_struct+0x3d9/0x520 kernel/rcu/srcutree.c:664
Code: c6 00 44 0e 8b 48 c7 c7 80 42 0e 8b 48 8b 8d 80 01 00 00 48 83 c4 20 5b 5d 41 5c 41 5d 83 e1 03 41 5e 41 5f e9 08 68 fa ff 90 <0f> 0b 90 eb aa 90 0f 0b 90 48 b8 00 00 00 00 00 fc ff df 4c 89 f2
RSP: 0018:ffffc900033cfcb0 EFLAGS: 00010202
RAX: dffffc0000000000 RBX: 0000000000000001 RCX: 0000000000000002
RDX: 1ffff1100f597531 RSI: ffffffff8158f30a RDI: ffffe8fffed21708
RBP: ffff88807acba800 R08: 0000000000000000 R09: 0000000000000008
R10: ffffffff8f9f4fd7 R11: 0000000000000000 R12: ffff8880ae104240
R13: ffff88807acba980 R14: ffff88807acba988 R15: ffffed1015c20849
FS: 000055556f23f480(0000) GS:ffff8880b9500000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f3b36579198 CR3: 000000002c59c000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
bch2_fs_btree_iter_exit+0x46e/0x630 fs/bcachefs/btree_iter.c:3279
__bch2_fs_free fs/bcachefs/super.c:562 [inline]
bch2_fs_release+0xfb/0x670 fs/bcachefs/super.c:610
kobject_cleanup lib/kobject.c:689 [inline]
kobject_release lib/kobject.c:720 [inline]
kref_put include/linux/kref.h:65 [inline]
kobject_put+0x1fa/0x5b0 lib/kobject.c:737
deactivate_locked_super+0xbe/0x1a0 fs/super.c:472
deactivate_super+0xde/0x100 fs/super.c:505
cleanup_mnt+0x222/0x450 fs/namespace.c:1267
task_work_run+0x14e/0x250 kernel/task_work.c:180
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x278/0x2a0 kernel/entry/common.c:218
do_syscall_64+0xdc/0x260 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f671907f057
Code: b0 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 0f 1f 44 00 00 31 f6 e9 09 00 00 00 66 0f 1f 84 00 00 00 00 00 b8 a6 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 01 c3 48 c7 c2 b0 ff ff ff f7 d8 64 89 02 b8
RSP: 002b:00007fffcd284548 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00007f671907f057
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007fffcd284600
RBP: 00007fffcd284600 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000246 R12: 00007fffcd2856c0
R13: 00007f67190c93b9 R14: 00000000001e28e3 R15: 0000000000000003
</TASK>


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