From mboxrd@z Thu Jan  1 00:00:00 1970
From: Paolo Bonzini <pbonzini@redhat.com>
Subject: Re: Calling to kvm_mmu_load
Date: Thu, 31 Oct 2013 10:52:26 +0100
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Cc: kvm <kvm@vger.kernel.org>, Jan Kiszka <jan.kiszka@web.de>
To: Arthur Chunqi Li <yzt356@gmail.com>
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Il 31/10/2013 09:05, Arthur Chunqi Li ha scritto:
>> >
>> > Basically everything that accesses the dirty_bitmap field of struct
>> > kvm_memory_slot is involved.  It all starts when the
>> > KVM_SET_USER_MEMORY_REGION ioctl is called with the
>> > KVM_MEM_LOG_DIRTY_PAGES flag set.
> I find the mechanism here is set all pages read-only to track all the
> dirty pages. But EPT provides such a dirty bit in EPT paging
> structures. Why don't we use this?

It doesn't provide it on all processors.  Check eptad in
/sys/module/kvm_intel/parameters.

Paolo