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Date: Tue, 08 Mar 2011 11:32:55 +0200
From: Avi Kivity <avi@redhat.com>
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Subject: [Qemu-devel] Re: kvm crashes with spice while loading qxl
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To: Paolo Bonzini <pbonzini@redhat.com>
Cc: kvm@vger.kernel.org, Marcelo Tosatti <mtosatti@redhat.com>, qemu-devel <qemu-devel@nongnu.org>, xming <xmingske@gmail.com>, Jan Kiszka <jan.kiszka@web.de>, Gerd Hoffmann <kraxel@redhat.com>

On 03/08/2011 11:28 AM, Paolo Bonzini wrote:
> On 03/08/2011 10:17 AM, Avi Kivity wrote:
>>> Memory map can be protected by a read-write lock initially, so that 
>>> vcpu
>>> thread holds it for read. Later can be converted to URCU.
>>
>> rwlock is insufficient, need a way to force the vcpu off so a writer can
>> actually do something.
>>
>> So we need some kind of priority rwlock where a reader lets the lock
>> know how it can force it off in case a writer comes along.
>
> If the reader is the VCPU thread, the VCPU thread can always be 
> bounced via qemu_cpu_kick.
>

Right, I just want the lock to do it automatically instead of sprinkling 
it everywhere we take a write lock.

-- 
error compiling committee.c: too many arguments to function