Re: [PATCH 03/12] KVM: MMU: lazily drop large spte

2013-08-02 Thread Xiao Guangrong
On Aug 3, 2013, at 4:27 AM, Marcelo Tosatti wrote: > On Fri, Aug 02, 2013 at 11:42:19PM +0800, Xiao Guangrong wrote: >> >> On Aug 2, 2013, at 10:55 PM, Marcelo Tosatti wrote: >> >>> On Tue, Jul 30, 2013 at 09:02:01PM +0800, Xiao Guangrong wrote: Currently, kvm zaps the large spte if writ

Re: [PATCH 03/12] KVM: MMU: lazily drop large spte

2013-08-02 Thread Marcelo Tosatti
On Fri, Aug 02, 2013 at 11:42:19PM +0800, Xiao Guangrong wrote: > > On Aug 2, 2013, at 10:55 PM, Marcelo Tosatti wrote: > > > On Tue, Jul 30, 2013 at 09:02:01PM +0800, Xiao Guangrong wrote: > >> Currently, kvm zaps the large spte if write-protected is needed, the later > >> read can fault on tha

Re: [PATCH 03/12] KVM: MMU: lazily drop large spte

2013-08-02 Thread Xiao Guangrong
On Aug 2, 2013, at 10:55 PM, Marcelo Tosatti wrote: > On Tue, Jul 30, 2013 at 09:02:01PM +0800, Xiao Guangrong wrote: >> Currently, kvm zaps the large spte if write-protected is needed, the later >> read can fault on that spte. Actually, we can make the large spte readonly >> instead of making t

Re: [PATCH 03/12] KVM: MMU: lazily drop large spte

2013-08-02 Thread Marcelo Tosatti
On Tue, Jul 30, 2013 at 09:02:01PM +0800, Xiao Guangrong wrote: > Currently, kvm zaps the large spte if write-protected is needed, the later > read can fault on that spte. Actually, we can make the large spte readonly > instead of making them un-present, the page fault caused by read access can > b

[PATCH 03/12] KVM: MMU: lazily drop large spte

2013-07-30 Thread Xiao Guangrong
Currently, kvm zaps the large spte if write-protected is needed, the later read can fault on that spte. Actually, we can make the large spte readonly instead of making them un-present, the page fault caused by read access can be avoided The idea is from Avi: | As I mentioned before, write-protecti