Re: blktests scsi/007 failure

Shin'ichiro Kawasaki
2023-04-14T08:58:16Z

On Apr 14, 2023 / 09:33, John Garry wrote:
> On 14/04/2023 08:36, Shin'ichiro Kawasaki wrote:
> > Hello Bart,
> >
> > Recently, I built a new blktests trial environment on QEMU. With this
> > environment, I observe scsi/007 failure. FYI, let me share blktests output [1]
> > and kernel message [2].
> >
>
> I did not notice which kernel you are using - did you mention it somewhere?

I forgot to mention it. Sorry. I observe the failure with kernel versions 6.2
and 6.3-rcX.

>
> > I found the failure depends on kernel configs for debug such as KASAN. When I
> > enable KASAN, the test case fails. When I disable KASAN, the test case passes.
> > It looks that the failure depends on the slow kernel (and/or slow machine).
> >
> > The test case sets 1 second to the block layer timeout to trigger the SCSI error
> > handler. It also sets 3 seconds to scsi_debug delay assuming the error handler
> > completes before the 3 seconds. From the kernel message, it looks that the error
> > handler takes longer than the 3 seconds delay, so I/O completes as success
> > before the error handler completion. This I/O success is not expected then the
> > test case fails. As a trial, I extended the scsi_debug delay time to 10 seconds,
> > then I observed the test case passes.
> >
> > Do you expect the I/O success by slow SCSI error handler? If so, the test case
> > needs improvement by extending the scsi_debug delay time.
>
> The failure may be due to one of my changes. Please see
> https://lore.kernel.org/lkml/5bdbfbbc-bac1-84a1-5f50-33a443e3292a@oracle.com/

Thanks for the notice. I think your changes were applied to 6.4/scsi-queue,
which I've not yet tried. Then it should not be related to your changes.