linux-kernel - Re: [PATCH 3/6] KVM: x86/mmu: avoid struct page in MMU

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <1624531381.4bht02wxsj.astroid@bobo.none>
Date:   Thu, 24 Jun 2021 20:43:29 +1000
From:   Nicholas Piggin <npiggin@...il.com>
To:     Marc Zyngier <maz@...nel.org>
Cc:     Aleksandar Markovic <aleksandar.qemu.devel@...il.com>,
        Alexandru Elisei <alexandru.elisei@....com>,
        Huacai Chen <chenhuacai@...nel.org>,
        dri-devel@...ts.freedesktop.org, intel-gfx@...ts.freedesktop.org,
        intel-gvt-dev@...ts.freedesktop.org,
        James Morse <james.morse@....com>,
        Jim Mattson <jmattson@...gle.com>,
        Joerg Roedel <joro@...tes.org>, kvmarm@...ts.cs.columbia.edu,
        kvm-ppc@...r.kernel.org, kvm@...r.kernel.org,
        linux-arm-kernel@...ts.infradead.org, linux-kernel@...r.kernel.org,
        linux-mips@...r.kernel.org, linuxppc-dev@...ts.ozlabs.org,
        Paul Mackerras <paulus@...abs.org>,
        Paolo Bonzini <pbonzini@...hat.com>,
        Sean Christopherson <seanjc@...gle.com>,
        David Stevens <stevensd@...omium.org>,
        Suzuki K Poulose <suzuki.poulose@....com>,
        Vitaly Kuznetsov <vkuznets@...hat.com>,
        Wanpeng Li <wanpengli@...cent.com>,
        Will Deacon <will@...nel.org>,
        Zhenyu Wang <zhenyuw@...ux.intel.com>,
        Zhi Wang <zhi.a.wang@...el.com>
Subject: Re: [PATCH 3/6] KVM: x86/mmu: avoid struct page in MMU

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@...il.com> wrote:
>> 
>> Excerpts from David Stevens's message of June 24, 2021 1:57 pm:
>> > From: David Stevens <stevensd@...omium.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;
>> >  }
>> 
>> How about
>> 
>>   kvm_release_pfn_page_clean(pfnpg);
> 
> 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.
> 
> 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