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Subject: Re: [PATCH 15/22] kvm: mmu: Support changed pte notifier in tdp MMU
To:     Ben Gardon <bgardon@google.com>, linux-kernel@vger.kernel.org,
        kvm@vger.kernel.org
Cc:     Cannon Matthews <cannonmatthews@google.com>,
        Peter Xu <peterx@redhat.com>,
        Sean Christopherson <sean.j.christopherson@intel.com>,
        Peter Shier <pshier@google.com>,
        Peter Feiner <pfeiner@google.com>,
        Junaid Shahid <junaids@google.com>,
        Jim Mattson <jmattson@google.com>,
        Yulei Zhang <yulei.kernel@gmail.com>,
        Wanpeng Li <kernellwp@gmail.com>,
        Vitaly Kuznetsov <vkuznets@redhat.com>,
        Xiao Guangrong <xiaoguangrong.eric@gmail.com>
References: <20200925212302.3979661-1-bgardon@google.com>
 <20200925212302.3979661-16-bgardon@google.com>
From:   Paolo Bonzini <pbonzini@redhat.com>
Message-ID: <dc3a8cb7-ea8d-9c4d-6341-95522b184a16@redhat.com>
Date:   Sat, 26 Sep 2020 02:33:04 +0200
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On 25/09/20 23:22, Ben Gardon wrote:
> @@ -1708,6 +1695,21 @@ static int kvm_unmap_rmapp(struct kvm *kvm, struct kvm_rmap_head *rmap_head,
>  	return kvm_zap_rmapp(kvm, rmap_head);
>  }
>  
> +u64 kvm_mmu_changed_pte_notifier_make_spte(u64 old_spte, kvm_pfn_t new_pfn)
> +{
> +	u64 new_spte;
> +
> +	new_spte = old_spte & ~PT64_BASE_ADDR_MASK;
> +	new_spte |= (u64)new_pfn << PAGE_SHIFT;
> +
> +	new_spte &= ~PT_WRITABLE_MASK;
> +	new_spte &= ~SPTE_HOST_WRITEABLE;
> +
> +	new_spte = mark_spte_for_access_track(new_spte);
> +
> +	return new_spte;
> +}
> +

And another. :)