Re: [PATCH 1/4] KVM: MMU: don't drop spte if overwrite it from W to RO

On 11/17/2010 04:24 AM, Marcelo Tosatti wrote: > On Fri, Nov 12, 2010 at 06:30:22PM +0800, Xiao Guangrong wrote: >> We just need flush tlb if overwrite a writable spte with a read-only one >> >> Signed-off-by: Xiao Guangrong >> --- >> arch/x86/kvm/mmu.c | 19 +-- >> 1 files chan

Re: [PATCH 1/4] KVM: MMU: don't drop spte if overwrite it from W to RO

On Fri, Nov 12, 2010 at 06:30:22PM +0800, Xiao Guangrong wrote: > We just need flush tlb if overwrite a writable spte with a read-only one > > Signed-off-by: Xiao Guangrong > --- > arch/x86/kvm/mmu.c | 19 +-- > 1 files changed, 9 insertions(+), 10 deletions(-) > > diff --git

Re: [PATCH 1/4] KVM: MMU: don't drop spte if overwrite it from W to RO

On 11/14/2010 06:52 PM, Avi Kivity wrote: > On 11/12/2010 12:30 PM, Xiao Guangrong wrote: >> We just need flush tlb if overwrite a writable spte with a read-only one >> > > What are the advantages? Avoid playing with rmap, and avoid a window > where the spte is missing? > Both, but only the fir

Re: [PATCH 1/4] KVM: MMU: don't drop spte if overwrite it from W to RO

On 11/12/2010 12:30 PM, Xiao Guangrong wrote: We just need flush tlb if overwrite a writable spte with a read-only one What are the advantages? Avoid playing with rmap, and avoid a window where the spte is missing? (they are worth the patch, just seeing if I'm not missing something) -- er

[PATCH 1/4] KVM: MMU: don't drop spte if overwrite it from W to RO

We just need flush tlb if overwrite a writable spte with a read-only one Signed-off-by: Xiao Guangrong --- arch/x86/kvm/mmu.c | 19 +-- 1 files changed, 9 insertions(+), 10 deletions(-) diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c index 4b6d54c..1a93ab4 100644 --- a/ar