On 2/3/21 3:06 PM, Greg Kroah-Hartman wrote: > 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... I'll take a look at this. -- Jens Axboe
