From mboxrd@z Thu Jan  1 00:00:00 1970
From: Andrea Arcangeli <aarcange@redhat.com>
Subject: Re: [PATCH 2/2] KVM: MMU: Flush TLBs only once in invlpg() before
 releasing mmu_lock
Date: Tue, 14 Feb 2012 18:21:50 +0100
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Cc: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>, avi@redhat.com,
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To: Takuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp>
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On Tue, Feb 14, 2012 at 01:56:17PM +0900, Takuya Yoshikawa wrote:
> (2012/02/14 13:36), Takuya Yoshikawa wrote:
> 
> > BTW, do you think that "kvm_mmu_flush_tlb()" should be moved inside of the
> > mmu_lock critical section?
> >
> 
> Ah, forget about this.  Trivially no.

Yes the reason is that it's the local flush and guest mode isn't
running if we're running that function so it's ok to run it later.

About the other change you did in this patch 2/2, I can't find the
code you're patching in the 3.2 upstream source, when I added the tlb
flush to invlpg, I immediately used a cumulative need_flush at the end
(before relasing mmu_lock of course).

   if (need_flush)
      kvm_flush_remote_tlbs(vcpu->kvm);