From mboxrd@z Thu Jan  1 00:00:00 1970
From: Avi Kivity <avi@redhat.com>
Subject: Re: KVM: protect concurrent make_all_cpus_request
Date: Thu, 18 Jun 2009 11:45:30 +0300
Message-ID: <4A39FEAA.4090100@redhat.com>
References: <20090617135347.GC14583@amt.cnet>
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Cc: kvm@vger.kernel.org, Andrea Arcangeli <aarcange@redhat.com>
To: Marcelo Tosatti <mtosatti@redhat.com>
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On 06/17/2009 04:53 PM, Marcelo Tosatti wrote:
> make_all_cpus_request contains a race condition which can
> trigger false request completed status, as follows:
>
> CPU0                                              CPU1
>
> if (test_and_set_bit(req,&vcpu->requests))
>     ....                                        	   if (test_and_set_bit(req,&vcpu->requests))
>     ..                                                  return
> proceed to smp_call_function_many(wait=1)
>
> Use a spinlock to serialize concurrent CPUs.
>
>    

Applied, thanks.

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