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From: Peter Maydell <peter.maydell@linaro.org>
Date: Thu, 14 Mar 2013 11:26:08 +0000
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Subject: Re: [Qemu-devel] [RFC PATCH 0/2] port network layer onto glib
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To: Paolo Bonzini <pbonzini@redhat.com>
Cc: mdroth <mdroth@linux.vnet.ibm.com>, "Michael S. Tsirkin" <mst@redhat.com>, Stefan Hajnoczi <stefanha@gmail.com>, qemu-devel@nongnu.org, Liu Ping Fan <qemulist@gmail.com>, Anthony Liguori <anthony@codemonkey.ws>

On 14 March 2013 11:04, Paolo Bonzini <pbonzini@redhat.com> wrote:
>>> > The gthread coroutine backend is really more for debugging than anything
>>> > else.  It works for qemu-io/img, but not for QEMU.  Good that you
>>> > actually found proof. :)
>> If it's not supposed to work we shouldn't let configure default
>> to it
>
> Agreed.  I thought it didn't anymore.

Nope, we still go ucontext -> gthread (and for platforms which don't
support ucontext we'll go straight to gthread).

I think we should probably be ucontext -> sigaltstack. The configure
code for this is a bit dodgy anyway (for instance there are paths
through it that can end up not setting coroutine_backend at all).
I'll submit a patch to tidy it up and not have gthread as our fallback.

-- PMM