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From: Gerd Hoffmann <kraxel@redhat.com>
Date: Fri, 15 Jul 2016 12:12:48 +0200
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Subject: Re: [Qemu-devel] Regression with commit 095497ffc66b7f031
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To: Paolo Bonzini <pbonzini@redhat.com>
Cc: Juergen Gross <jgross@suse.com>, Peter Lieven <pl@kamp.de>, xen-devel <xen-devel@lists.xenproject.org>, "qemu-devel@nongnu.org" <qemu-devel@nongnu.org>

On Fr, 2016-07-15 at 12:02 +0200, Paolo Bonzini wrote:
>=20
> On 15/07/2016 10:47, Juergen Gross wrote:
> > Nothing scaring and no real difference between working and not working
> > variant.
> >=20
> > Meanwhile I've been digging a little bit deeper and found the reason:
> > libxenstore is setting up a reader thread which is waiting for the
> > watch to fire. With above commit the stack size of that thread (16kB)
> > is too small. Setting it to 32kB made qemu work again.
>=20
> This makes very little sense (not your fault)...  The commit doesn't
> change stack usage at all, TLS should not be on the stack.
>=20
> Can you capture a backtrace where the 16K stack is exceeded?  Perhaps
> it's only due to inlining decision on the compiler, in which case
> Peter's patch from today is only a bandaid.

Hmm, I guess I hold off the vnc pull request for now ...

cheers,
  Gerd