[moderation] INFO: The task syz-executor:NUM has been waiting for writeback completion for more than NUM seconds.

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: cc3aa43b44bd Add linux-next specific files for 20251219
git tree: linux-next
console output: https://syzkaller.appspot.com/x/log.txt?x=11f88a22580000
kernel config: https://syzkaller.appspot.com/x/.config?x=da1bc82c6189c463
dashboard link: https://syzkaller.appspot.com/bug?extid=9aa5b9a263c658890082
compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/30bf539e6f28/disk-cc3aa43b.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/0e2f8b08e342/vmlinux-cc3aa43b.xz
kernel image: https://storage.googleapis.com/syzbot-assets/ec7ee6ece11f/bzImage-cc3aa43b.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+9aa5b9...@syzkaller.appspotmail.com

INFO: The task syz-executor:5828 has been waiting for writeback completion for more than 143 seconds.
INFO: The task syz-executor:5828 has been waiting for writeback completion for more than 143 seconds.
INFO: The task syz-executor:5828 has been waiting for writeback completion for more than 143 seconds.
NILFS (loop2): I/O error writing log (start-blocknr=80, block-count=12) in segment 5
NILFS (loop2): I/O error writing log (start-blocknr=80, block-count=12) in segment 5
NILFS (loop2): I/O error writing log (start-blocknr=80, block-count=12) in segment 5
NILFS (loop2): I/O error writing log (start-blocknr=80, block-count=12) in segment 5
NILFS (loop2): disposed unprocessed dirty file(s) when stopping log writer
Buffer I/O error on dev loop2, logical block 0, lost sync page write
NILFS (loop2): unable to write superblock: err=-5
Buffer I/O error on dev loop2, logical block 511, lost sync page write
NILFS (loop2): unable to write superblock: err=-5


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