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Date: Wed, 11 May 2011 07:51:33 -0500
From: Anthony Liguori <anthony@codemonkey.ws>
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Subject: Re: [Qemu-devel] [PATCH 1/2] coroutine: introduce coroutines
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To: Paolo Bonzini <pbonzini@redhat.com>
Cc: Kevin Wolf <kwolf@redhat.com>, Anthony Liguori <aliguori@us.ibm.com>, Venkateswararao Jujjuri <jvrao@linux.vnet.ibm.com>, Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>, qemu-devel@nongnu.org

On 05/11/2011 07:04 AM, Paolo Bonzini wrote:
> On 05/11/2011 12:15 PM, Stefan Hajnoczi wrote:
>> +#ifdef __i386__
>> + asm volatile(
>> + "mov %%esp, %%ebx;"
>> + "mov %0, %%esp;"
>> + "pushl %1;"
>> + "call _trampoline;"
>> + "mov %%ebx, %%esp;"
>> + : : "r" (co->stack + co->stack_size), "r" (co) : "ebx"
>> + );
>
> This is incomplete, it should set FS:[4] and FS:[8] to top and bottom of
> stack respectively, otherwise exception handling (including SIGSEGV) is
> broken. But I think for Windows it's anyway better to use fibers. Commit
> this and either I or Stefan Weil will fix it. :)
>
> Acked-by: Paolo Bonzini <pbonzini@redhat.com>

How about a generic thread fallback?  That's what we do in gtk-vnc and 
it solves the portability issue in a very robust way.

Regards,

Anthony Liguori

>
> Paolo
>