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

From: Randall S. Becker <rsbecker@nexbridge.com>
Date: Feb 14, 2019, 22:59 UTC
Message-ID: <005801d4c4b8$e5669980$b033cc80$@nexbridge.com>
In-Reply-To: <20190214223334.GE3064@jessie.local>

On February 14, 2019 17:34, Max Kirillov wrote:

Show 18 quoted lines

> 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.