Re: [syzbot] WARNING in btrfs_sync_log

[David Sterba <dsterba@suse.cz>]

On Sun, Oct 16, 2022 at 01:36:42PM -0700, syzbot wrote:
> Hello,
> 
> syzbot found the following issue on:
> 
> HEAD commit:    493ffd6605b2 Merge tag 'ucount-rlimits-cleanups-for-v5.19'..
> git tree:       upstream
> console output: https://syzkaller.appspot.com/x/log.txt?x=12c65b84880000
> kernel config:  https://syzkaller.appspot.com/x/.config?x=d19f5d16783f901
> dashboard link: https://syzkaller.appspot.com/bug?extid=4406ed3884d139266b67
> compiler:       Debian clang version 13.0.1-++20220126092033+75e33f71c2da-1~exp1~20220126212112.63, GNU ld (GNU Binutils for Debian) 2.35.2
> 
> Unfortunately, I don't have any reproducer for this issue yet.
> 
> Downloadable assets:
> disk image: https://storage.googleapis.com/syzbot-assets/f1ff6481e26f/disk-493ffd66.raw.xz
> vmlinux: https://storage.googleapis.com/syzbot-assets/101bd3c7ae47/vmlinux-493ffd66.xz
> 
> IMPORTANT: if you fix the issue, please add the following tag to the commit:
> Reported-by: syzbot+4406ed3884d139266b67@syzkaller.appspotmail.com
> 
> loop0: detected capacity change from 0 to 32768
> BTRFS info (device loop0): using xxhash64 (xxhash64-generic) checksum algorithm
> BTRFS info (device loop0): using free space tree
> BTRFS info (device loop0): enabling ssd optimizations
> ------------[ cut here ]------------
> WARNING: CPU: 0 PID: 30197 at fs/btrfs/tree-log.c:3081 btrfs_sync_log+0x1ebd/0x2d40 fs/btrfs/tree-log.c:3081

That was an injected ENOMEM that then hit a transaction abort, we used
to print a full trace on that but it's been silenced.

#syz fix: btrfs: don't print stack trace when transaction is aborted due to ENOMEM