Re: [PATCH 0/5]stop normal completion path entering a timeout req

From: Christoph Hellwig
Date: Fri Jun 22 2018 - 11:01:23 EST


On Thu, Jun 21, 2018 at 04:22:22PM +0800, jianchao.wang wrote:
> > Trace, please. With the latest kernel. I'm not saying that there
> > is nothing to fix, but the mode of never completing once timeout
> > requests as currently done is SCSI is clearly broken.
> >
>
> I didn't find the existing method to simulate this.
> So I modified the scsi-debug as following patch as install it as following:
> modprobe scsi-debug delay=-1 ndelay=-1
> Both 4.17-rc1 and 4.18-rc1 with this patch set could survive from the test.

What tree is this against? I can't apply it to either current Linus'
tree or 4.17 for that matter.

Also I'm not sure this blk_abort_request call is representative
of the real world. Drivers do drain their queues before calling
it in general, e.g. take a look at ata_eh_set_pending for the
probably most common user.