Message-ID: <4CFB8CC5.50902@redhat.com>
Date: Sun, 05 Dec 2010 14:59:49 +0200
From: Avi Kivity <avi@redhat.com>
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To: Rik van Riel <riel@redhat.com>
CC: vatsa@linux.vnet.ibm.com, kvm@vger.kernel.org,
        linux-kernel@vger.kernel.org, Peter Zijlstra <a.p.zijlstra@chello.nl>,
        Ingo Molnar <mingo@elte.hu>,
        Anthony Liguori <aliguori@linux.vnet.ibm.com>
Subject: Re: [RFC PATCH 1/3] kvm: keep track of which task is running a KVM
 vcpu
References: <20101202144129.4357fe00@annuminas.surriel.com> <20101202144324.4a79263b@annuminas.surriel.com> <20101203121746.GE27994@linux.vnet.ibm.com> <4CF8FBAA.7000807@redhat.com>
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On 12/03/2010 04:16 PM, Rik van Riel wrote:
> On 12/03/2010 07:17 AM, Srivatsa Vaddagiri wrote:
>> On Thu, Dec 02, 2010 at 02:43:24PM -0500, Rik van Riel wrote:
>>>       mutex_lock(&vcpu->mutex);
>>> +    vcpu->task = current;
>>
>> Shouldn't we grab reference to current task_struct before storing a 
>> pointer to
>> it?
>
> That should not be needed, since current cannot go away without
> setting vcpu->task back to NULL in vcpu_put.
>

However, you do reference vcpu->task from other contexts.  So some sort 
of safe reference is needed.

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

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