From mboxrd@z Thu Jan  1 00:00:00 1970
From: Zachary Amsden <zach@vmware.com>
Subject: Re: [PATCH 2/5] Paravirt cpu batching.patch
Date: Tue, 12 Dec 2006 16:38:57 -0800
Message-ID: <457F4BA1.4010700@vmware.com>
References: <200612121853_MC3-1-D4D2-191A@compuserve.com>
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To: Chuck Ebbert <76306.1226@compuserve.com>
Cc: Chris Wright <chrisw@sous-sol.org>, Andrew Morton <akpm@osdl.org>, Andi Kleen <ak@muc.de>, Linux Kernel Mailing List <linux-kernel@vger.kernel.org>, Virtualization Mailing List <virtualization@lists.osdl.org>
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Chuck Ebbert wrote:
> In-Reply-To: <20061212225430.GC10475@sequoia.sous-sol.org>
>
> On Tue, 12 Dec 2006 14:54:30 -0800, Chros Wright wrote:
>
>   =

>>> --- a/arch/i386/kernel/process.c    Tue Dec 12 13:50:50 2006 -0800
>>> +++ b/arch/i386/kernel/process.c    Tue Dec 12 13:50:53 2006 -0800
>>> @@ -665,6 +665,37 @@ struct task_struct fastcall * __switch_t
>>>     load_TLS(next, cpu);
>>>  =

>>>     /*
>>> +    * Restore IOPL if needed.
>>> +    */
>>> +   if (unlikely(prev->iopl !=3D next->iopl))
>>> +           set_iopl_mask(next->iopl);
>>>       =

>> Small sidenote that this bit undoes a recent change from Chuck Ebbert, w=
hich
>> killed iopl_mask update via hypervisor.
>>     =

>
> This whole thing needs a proper fix IMO.  I posted something a while back
> but Andi didn't like it, I guess.
>   =


We can handle this one with an #ifdef CONFIG_PARAVIRT, though.

Zach