Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
Date:   Thu, 24 Jun 2021 20:43:29 +1000
From:   Nicholas Piggin <npiggin@gmail.com>
Subject: Re: [PATCH 3/6] KVM: x86/mmu: avoid struct page in MMU
To:     Marc Zyngier <maz@kernel.org>
Cc:     Aleksandar Markovic <aleksandar.qemu.devel@gmail.com>,
        Alexandru Elisei <alexandru.elisei@arm.com>,
        Huacai Chen <chenhuacai@kernel.org>,
        dri-devel@lists.freedesktop.org, intel-gfx@lists.freedesktop.org,
        intel-gvt-dev@lists.freedesktop.org,
        James Morse <james.morse@arm.com>,
        Jim Mattson <jmattson@google.com>,
        Joerg Roedel <joro@8bytes.org>, kvmarm@lists.cs.columbia.edu,
        kvm-ppc@vger.kernel.org, kvm@vger.kernel.org,
        linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org,
        linux-mips@vger.kernel.org, linuxppc-dev@lists.ozlabs.org,
        Paul Mackerras <paulus@ozlabs.org>,
        Paolo Bonzini <pbonzini@redhat.com>,
        Sean Christopherson <seanjc@google.com>,
        David Stevens <stevensd@chromium.org>,
        Suzuki K Poulose <suzuki.poulose@arm.com>,
        Vitaly Kuznetsov <vkuznets@redhat.com>,
        Wanpeng Li <wanpengli@tencent.com>,
        Will Deacon <will@kernel.org>,
        Zhenyu Wang <zhenyuw@linux.intel.com>,
        Zhi Wang <zhi.a.wang@intel.com>
References: <20210624035749.4054934-1-stevensd@google.com>
        <20210624035749.4054934-4-stevensd@google.com>
        <1624524744.2sr7o7ix86.astroid@bobo.none> <87mtrfinks.wl-maz@kernel.org>
In-Reply-To: <87mtrfinks.wl-maz@kernel.org>
MIME-Version: 1.0
Message-Id: <1624531381.4bht02wxsj.astroid@bobo.none>
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: quoted-printable
Precedence: bulk

Excerpts from Marc Zyngier's message of June 24, 2021 8:06 pm:
> On Thu, 24 Jun 2021 09:58:00 +0100,
> Nicholas Piggin <npiggin@gmail.com> wrote:
>>=20
>> Excerpts from David Stevens's message of June 24, 2021 1:57 pm:
>> > From: David Stevens <stevensd@chromium.org>
>> >  out_unlock:
>> >  	if (is_tdp_mmu_root(vcpu->kvm, vcpu->arch.mmu->root_hpa))
>> >  		read_unlock(&vcpu->kvm->mmu_lock);
>> >  	else
>> >  		write_unlock(&vcpu->kvm->mmu_lock);
>> > -	kvm_release_pfn_clean(pfn);
>> > +	if (pfnpg.page)
>> > +		put_page(pfnpg.page);
>> >  	return r;
>> >  }
>>=20
>> How about
>>=20
>>   kvm_release_pfn_page_clean(pfnpg);
>=20
> I'm not sure. I always found kvm_release_pfn_clean() ugly, because it
> doesn't mark the page 'clean'. I find put_page() more correct.
>=20
> Something like 'kvm_put_pfn_page()' would make more sense, but I'm so
> bad at naming things that I could just as well call it 'bob()'.

That seems like a fine name to me. A little better than bob.

Thanks,
Nick