Subject: RE: [PATCH 0/1] Fix hang in t5562, introduced in v2.21.0-rc1

From: "Randall S. Becker" <[email-masked]>
Date: Thu, 14 Feb 2019 17:59:04 -0500

On February 14, 2019 17:34, Max Kirillov wrote:
> On Thu, Feb 14, 2019 at 05:17:26PM -0500, Randall S. Becker wrote:
> > Unfortunately, subtest 13 still hangs on NonStop, even with this
> > patch, so our Pipeline still hangs. I'm glad it's better on Azure, but
> > I don't think this actually addresses the root cause of the hang. This
> > is now the fourth attempt at fixing this. Is it possible this is not
> > the test that is failing, but actually the git-http-backend? The code
> > is not in a loop, if that helps. It is not consuming any significant
> > cycles. I don't know that part of the code at all, sadly. The code is
> > here:
> >
> > * in the operating system from here up *
> >   cleanup_children + 0x5D0 (UCr)
> 
> ... so does the process which the stack was taken from has any children
> processes still?
> 
> I could imagine if a child somehow manages to end up in uninterruptible
> sleep, then probably it would never complete this way, wouldn't it?

>From what I can tell (previously reported), none of the children are dead.
git-http-backend is waiting and the others are in a read state. I can try to
get full stack traces once the current cycle ends.