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Message-ID: <eb14c183-ef60-2e3b-839b-617ed39a5eea@redhat.com>
Date:   Wed, 29 Sep 2021 13:14:55 +0200
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Subject: Re: [PATCH v3 31/31] KVM: MMU: make spte an in-out argument in
 make_spte
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To:     David Matlack <dmatlack@google.com>
Cc:     linux-kernel@vger.kernel.org, kvm@vger.kernel.org,
        seanjc@google.com
References: <20210924163152.289027-1-pbonzini@redhat.com>
 <20210924163152.289027-32-pbonzini@redhat.com> <YVOjSSahzJ/tf28g@google.com>
From:   Paolo Bonzini <pbonzini@redhat.com>
In-Reply-To: <YVOjSSahzJ/tf28g@google.com>
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On 29/09/21 01:20, David Matlack wrote:
>>   bool make_spte(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp,
>>   	       struct kvm_memory_slot *slot,
>>   	       unsigned int pte_access, gfn_t gfn, kvm_pfn_t pfn,
>> -	       u64 old_spte, bool speculative, bool can_unsync,
>> -	       bool host_writable, u64 *new_spte)
>> +	       bool speculative, bool can_unsync,
>> +	       bool host_writable, u64 *sptep)
> I'd prefer a different name since `sptep` has specific meaning
> throughout the mmu code. (It's the address of the spte in the page
> table.)
> 
> Case in point, I was going to suggest we can get rid of struct
> kvm_mmu_page since it can be derived from the sptep and then realized
> how wrong that was:).
> 
> Instead of receiving the new spte as a parameter what do you think about
> changing make_spte to return the new spte? I think that would make the
> code more readable (but won't reduce the number of arguments because
> you'd have to add wrprot).
> 

You have a point.  I've dropped this patch for now.

Paolo