Re: [bug report] WARNING: CPU: 5 PID: 679 at io_uring/io_uring.c:2835 io_ring_exit_work+0x2b6/0x2e0

[Ming Lei <ming.lei@redhat.com>]

On Tue, Apr 16, 2024 at 10:26:16AM +0800, Changhui Zhong wrote:
> > >
> > > I can't reproduce this here, fwiw. Ming, something you've seen?
> >
> > I just test against the latest for-next/block(-rc4 based), and still can't
> > reproduce it. There was such RH internal report before, and maybe not
> > ublk related.
> >
> > Changhui, if the issue can be reproduced in your machine, care to share
> > your machine for me to investigate a bit?
> >
> > Thanks,
> > Ming
> >
> 
> I still can reproduce this issue on my machine，
> and I shared machine to Ming，he can do more investigation for this issue，
> 
> [ 1244.207092] running generic/006
> [ 1246.456896] blk_print_req_error: 77 callbacks suppressed
> [ 1246.456907] I/O error, dev ublkb1, sector 2395864 op 0x1:(WRITE)
> flags 0x8800 phys_seg 1 prio class 0

The failure is actually triggered in recovering qcow2 target in generic/005,
since ublkb0 isn't removed successfully in generic/005.

git-bisect shows that the 1st bad commit is cca6571381a0 ("io_uring/rw:
cleanup retry path").

And not see any issue in uring command side, so the trouble seems
in normal io_uring rw side over XFS file, and not related with block
device.


Thanks,
Ming