linux-kernel - Re: [PATCH 3/6] x86, kvm: use kernel_fpu_begin/end() in kvm_load/put_guest

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Message-ID: <5059FF67.6050005@redhat.com>
Date:	Wed, 19 Sep 2012 20:22:47 +0300
From:	Avi Kivity <avi@...hat.com>
To:	Suresh Siddha <suresh.b.siddha@...el.com>
CC:	hpa@...or.com, mingo@...nel.org, torvalds@...ux-foundation.org,
	andreas.herrmann3@....com, bp@...64.org, robert.richter@....com,
	linux-kernel@...r.kernel.org
Subject: Re: [PATCH 3/6] x86, kvm: use kernel_fpu_begin/end() in kvm_load/put_guest_fpu()

On 09/19/2012 08:18 PM, Suresh Siddha wrote:

> These routines (kvm_load/put_guest_fpu()) are already called with
> preemption disabled but as you mentioned, we don't want the preemption
> to be disabled completely between the kvm_load_guest_fpu() and
> kvm_put_guest_fpu().
> 
> Also KVM already has the preempt notifier which is doing the
> kvm_put_guest_fpu(), so something like the appended should address this.
> I will test this shortly.
> 

Note, we could also go in a different direction and make
kernel_fpu_begin() use preempt notifiers and thus make its users
preemptible.  But that's for a separate patchset.

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