On Wed, Feb 03, 2021 at 01:28:26PM -0800, Andres Freund wrote: > Hi, > > On 2021-02-03 14:03:09 +0100, Greg Kroah-Hartman wrote: > > > On v5.4.43-101-gbba91cdba612 this fails with > > > fio: io_u error on file /mnt/t2/test.0.0: Input/output error: write offset=0, buflen=4096 > > > fio: pid=734, err=5/file:io_u.c:1834, func=io_u error, error=Input/output error > > > > > > whereas previously it worked. libaio still works... > > > > > > I haven't checked which major kernel version fixed this again, but I did > > > verify that it's still broken in 5.4.94 and that 5.10.9 works. > > > > > > I would suspect it's > > > > > > commit 4503b7676a2e0abe69c2f2c0d8b03aec53f2f048 > > > Author: Jens Axboe <axboe@xxxxxxxxx> > > > Date: 2020-06-01 10:00:27 -0600 > > > > > > io_uring: catch -EIO from buffered issue request failure > > > > > > -EIO bubbles up like -EAGAIN if we fail to allocate a request at the > > > lower level. Play it safe and treat it like -EAGAIN in terms of sync > > > retry, to avoid passing back an errant -EIO. > > > > > > Catch some of these early for block based file, as non-mq devices > > > generally do not support NOWAIT. That saves us some overhead by > > > not first trying, then retrying from async context. We can go straight > > > to async punt instead. > > > > > > Signed-off-by: Jens Axboe <axboe@xxxxxxxxx> > > > > > > > > > which isn't in stable/linux-5.4.y > > > > Can you test that if the above commit is added, all works well again? > > It doesn't apply cleanly, I'll try to resolve the conflict. However, I > assume that the revert was for a concrete reason - but I can't quite > figure out what b0beb28097fa04177b3769f4bb7a0d0d9c4ae76e was concretely > solving, and whether reverting the revert in 5.4 would re-introduce a > different problem. > > commit b0beb28097fa04177b3769f4bb7a0d0d9c4ae76e (tag: block-5.7-2020-05-29, linux-block/block-5.7) > Author: Jens Axboe <axboe@xxxxxxxxx> > Date: 2020-05-28 13:19:29 -0600 > > Revert "block: end bio with BLK_STS_AGAIN in case of non-mq devs and REQ_NOWAIT" > > This reverts commit c58c1f83436b501d45d4050fd1296d71a9760bcb. > > io_uring does do the right thing for this case, and we're still returning > -EAGAIN to userspace for the cases we don't support. Revert this change > to avoid doing endless spins of resubmits. > > Cc: stable@xxxxxxxxxxxxxxx # v5.6 > Reported-by: Bijan Mottahedeh <bijan.mottahedeh@xxxxxxxxxx> > Signed-off-by: Jens Axboe <axboe@xxxxxxxxx> > > I suspect it just wasn't aimed at 5.4, and that's that, but I'm not > sure. In which case presumably reverting > bba91cdba612fbce4f8575c5d94d2b146fb83ea3 would be the right fix, not > backporting 4503b7676a2e0abe69c2f2c0d8b03aec53f2f048 et al. Ok, can you send a revert patch for this? But it would be good to get Jens to weigh in on this... thanks, greg k-h
