On Wed, Apr 09, 2025 at 04:09:41PM +0000, Charalampos Mitrodimas wrote: > syzbot <[email protected]> writes: > > > Hello, > > > > syzbot found the following issue on: > > > > HEAD commit: a4cda136f021 Add linux-next specific files for 20250404 > > git tree: linux-next > > console+strace: https://syzkaller.appspot.com/x/log.txt?x=12c3db4c580000 > > kernel config: https://syzkaller.appspot.com/x/.config?x=8a257c454bb1afb7 > > dashboard link: https://syzkaller.appspot.com/bug?extid=aec9606169fbc3a12ca6 > > compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for > > Debian) 2.40 > > syz repro: https://syzkaller.appspot.com/x/repro.syz?x=17ca0c04580000 > > C reproducer: https://syzkaller.appspot.com/x/repro.c?x=11c3db4c580000 > > > > Downloadable assets: > > disk image: > > https://storage.googleapis.com/syzbot-assets/59048bc9c206/disk-a4cda136.raw.xz > > vmlinux: > > https://storage.googleapis.com/syzbot-assets/ad2ba7306f20/vmlinux-a4cda136.xz > > kernel image: > > https://storage.googleapis.com/syzbot-assets/b3bef7acbf10/bzImage-a4cda136.xz > > mounted in repro: > > https://storage.googleapis.com/syzbot-assets/110624be1513/mount_0.gz > > > > The issue was bisected to: > > > > commit dcffc3b1ae3251d796a25c673f614e3099ca83d3 > > Author: Kent Overstreet <[email protected]> > > Date: Sun Mar 30 03:11:08 2025 +0000 > > > > bcachefs: Split up bch_dev.io_ref > > > > bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=13948c04580000 > > final oops: https://syzkaller.appspot.com/x/report.txt?x=10548c04580000 > > console output: https://syzkaller.appspot.com/x/log.txt?x=17948c04580000 > > > > IMPORTANT: if you fix the issue, please add the following tag to the commit: > > Reported-by: [email protected] > > Fixes: dcffc3b1ae32 ("bcachefs: Split up bch_dev.io_ref") > > > > bcachefs (loop0): shutting down > > ------------[ cut here ]------------ > > WARNING: CPU: 0 PID: 5844 at fs/bcachefs/super.c:1229 > > bch2_dev_free+0x228/0x290 fs/bcachefs/super.c:1229 > > Modules linked in: > > CPU: 0 UID: 0 PID: 5844 Comm: syz-executor121 Not tainted > > 6.14.0-next-20250404-syzkaller #0 PREEMPT(full) > > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS > > Google 02/12/2025 > > RIP: 0010:bch2_dev_free+0x228/0x290 fs/bcachefs/super.c:1229 > > Code: ff e8 4c cf 74 00 4c 89 ef e8 44 cf 74 00 48 89 df 48 83 c4 10 5b 41 > > 5c 41 5d 41 5e 41 5f 5d e9 ee 53 96 07 e8 59 e9 32 fd 90 <0f> 0b 90 e9 09 > > fe ff ff e8 4b e9 32 fd 90 0f 0b 90 e9 15 fe ff ff > > RSP: 0018:ffffc9000406fb88 EFLAGS: 00010293 > > RAX: ffffffff849073d7 RBX: ffff888035282000 RCX: ffff888034af9e00 > > RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 > > RBP: ffff8880352820c0 R08: ffffffff850552f7 R09: 0000000000000000 > > R10: ffff888035282208 R11: ffffed1006a5044a R12: ffff888075e003f0 > > R13: ffff8880352820b0 R14: ffff888075e00000 R15: ffff888075e007b2 > > FS: 000055558bb20380(0000) GS:ffff888124f8f000(0000) knlGS:0000000000000000 > > CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > > CR2: 000000000045bdd0 CR3: 00000000122a0000 CR4: 00000000003526f0 > > DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 > > DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 > > Call Trace: > > <TASK> > > bch2_fs_free+0x2b0/0x400 fs/bcachefs/super.c:688 > > deactivate_locked_super+0xc4/0x130 fs/super.c:473 > > cleanup_mnt+0x422/0x4c0 fs/namespace.c:1435 > > task_work_run+0x251/0x310 kernel/task_work.c:227 > > ptrace_notify+0x2dc/0x390 kernel/signal.c:2520 > > ptrace_report_syscall include/linux/ptrace.h:415 [inline] > > ptrace_report_syscall_exit include/linux/ptrace.h:477 [inline] > > syscall_exit_work+0xc7/0x1d0 kernel/entry/common.c:173 > > syscall_exit_to_user_mode_prepare kernel/entry/common.c:200 [inline] > > __syscall_exit_to_user_mode_work kernel/entry/common.c:205 [inline] > > syscall_exit_to_user_mode+0x24a/0x340 kernel/entry/common.c:218 > > do_syscall_64+0x100/0x230 arch/x86/entry/syscall_64.c:100 > > entry_SYSCALL_64_after_hwframe+0x77/0x7f > > RIP: 0033:0x7f49b0cec447 > > Code: 07 00 48 83 c4 08 5b 5d c3 66 2e 0f 1f 84 00 00 00 00 00 c3 66 2e 0f > > 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 a6 00 00 00 0f 05 <48> 3d 00 f0 ff > > ff 77 01 c3 48 c7 c2 b8 ff ff ff f7 d8 64 89 02 b8 > > RSP: 002b:00007ffd94723978 EFLAGS: 00000206 ORIG_RAX: 00000000000000a6 > > RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00007f49b0cec447 > > RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffd94723a30 > > RBP: 00007ffd94723a30 R08: 0000000000000000 R09: 0000000000000000 > > R10: 00000000ffffffff R11: 0000000000000206 R12: 00007ffd94724aa0 > > R13: 000055558bb216c0 R14: 0000000000000001 R15: 431bde82d7b634db > > </TASK> > > > > > > --- > > #syz test > > From: Charalampos Mitrodimas <[email protected]> > Subject: [PATCH] bcachefs: Fix WARN_ON in bch2_dev_free > > After splitting bch_dev.io_ref into separate READ and WRITE refs, we > need to ensure both refs are properly stopped before freeing a device. > Add bch2_dev_io_ref_stop(ca, WRITE) to bch2_fs_free() to prevent the > WARNING in bch2_dev_free(). > > Reported-by: [email protected] > Fixes: dcffc3b1ae32 ("bcachefs: Split up bch_dev.io_ref") > Signed-off-by: Charalampos Mitrodimas <[email protected]> > --- > fs/bcachefs/super.c | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/fs/bcachefs/super.c b/fs/bcachefs/super.c > index a58edde43bee..089b69b685d9 100644 > --- a/fs/bcachefs/super.c > +++ b/fs/bcachefs/super.c > @@ -684,6 +684,7 @@ void bch2_fs_free(struct bch_fs *c) > if (ca) { > EBUG_ON(atomic_long_read(&ca->ref) != 1); > bch2_dev_io_ref_stop(ca, READ); > + bch2_dev_io_ref_stop(ca, WRITE); > bch2_free_super(&ca->disk_sb); > bch2_dev_free(ca); > } > -- > 2.39.5 >
This would seem to indicate shutting down without going read-only, there might be a deeper bug here
