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Message-ID: <4988FA4A.6080002@goop.org>
Date: Tue, 03 Feb 2009 18:15:38 -0800
From: Jeremy Fitzhardinge <jeremy@goop.org>
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To: "H. Peter Anvin" <hpa@kernel.org>
CC: Ingo Molnar <mingo@elte.hu>, the arch/x86 maintainers <x86@kernel.org>,
       Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
       Xen-devel <xen-devel@lists.xensource.com>,
       Stable Kernel <stable@kernel.org>
Subject: Re: [PATCH] xen: disable interrupts before saving in percpu
References: <4988DAEA.6040608@goop.org> <4988EE04.7090006@kernel.org>
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H. Peter Anvin wrote:
> Jeremy Fitzhardinge wrote:
>   
>> xen_mc_batch has a small preempt race where it takes the address of a
>> percpu variable immediately before disabling interrupts, thereby
>> leaving a small window in which we may migrate to another cpu and save
>> the flags in the wrong percpu variable.  Disable interrupts before
>> saving the old flags in a percpu.
>>     
>
> Applied to tip:core/xen, thanks!

Can you push this Linusward too?

Thanks,
    J