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Date: Fri, 6 Mar 2009 22:06:38 +0300 (MSK)
From: malc <av1474@comtv.ru>
Subject: Re: [Qemu-devel] [RFC][PATCH] Fix race condition on access to
	env->interrupt_request
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To: qemu-devel@nongnu.org

On Fri, 6 Mar 2009, Aurelien Jarno wrote:

> env->interrupt_request is accessed as the bit level from both main code
> and signal handler, making a race condition possible even on CISC CPU. 
> This causes freeze of QEMU under high load when running the dyntick 
> clock.
> 
> The patch below move the bit corresponding to CPU_INTERRUPT_EXIT in a
> separate variable, declared as volatile sig_atomic_t, so it should be
> work even on RISC CPU.
> 
> We may want to move the cpu_interrupt(env, CPU_INTERRUPT_EXIT) case in
> its own function and get rid of CPU_INTERRUPT_EXIT. That can be done
> later, I wanted to keep the patch short for easier review.
> 
> Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
> 

Looks good.

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