Re: [syzbot] [btrfs?] kernel BUG in can_finish_ordered_extent

[David Sterba]

On Sun, Aug 25, 2024 at 05:03:25AM -0700, syzbot wrote:
> Hello,
> 
> syzbot found the following issue on:
> 
> HEAD commit:    c79c85875f1a Add linux-next specific files for 20240823
> git tree:       linux-next
> console output: https://syzkaller.appspot.com/x/log.txt?x=177d1305980000
> kernel config:  https://syzkaller.appspot.com/x/.config?x=23bc95d9a9b56fa4
> dashboard link: https://syzkaller.appspot.com/bug?extid=f88e7f8eca12247510dc
> compiler:       Debian clang version 15.0.6, 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/8bbbc2af33d9/disk-c79c8587.raw.xz
> vmlinux: https://storage.googleapis.com/syzbot-assets/e25f34cd29db/vmlinux-c79c8587.xz
> kernel image: https://storage.googleapis.com/syzbot-assets/1c0f92a7043e/bzImage-c79c8587.xz
> 
> IMPORTANT: if you fix the issue, please add the following tag to the commit:
> Reported-by: syzbot+f88e7f8eca12247510dc@xxxxxxxxxxxxxxxxxxxxxxxxx
> 
> assertion failed: folio->mapping, in fs/btrfs/ordered-data.c:344
> ------------[ cut here ]------------
> kernel BUG at fs/btrfs/ordered-data.c:344!

This is probably because of the folio conversion series
https://lore.kernel.org/linux-btrfs/20240822013714.3278193-1-lizetao1@xxxxxxxxxx/

that I added to linux-next for testing. I've removed again as there were
more problems found. I'll keep the report open to see if the crash
happens again.