From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sean Christopherson Date: Mon, 5 Aug 2024 16:53:01 -0700 Subject: [PATCH v12 54/84] KVM: arm64: Mark "struct page" pfns accessed/dirty before dropping mmu_lock In-Reply-To: References: <20240726235234.228822-1-seanjc@google.com> <20240726235234.228822-55-seanjc@google.com> Message-ID: List-Id: To: kvm-riscv@lists.infradead.org MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit On Mon, Aug 05, 2024, Oliver Upton wrote: > > > --- > > > arch/arm64/kvm/mmu.c | 10 ++++++---- > > > 1 file changed, 6 insertions(+), 4 deletions(-) > > > > > > diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c > > > index 22ee37360c4e..ce13c3d884d5 100644 > > > --- a/arch/arm64/kvm/mmu.c > > > +++ b/arch/arm64/kvm/mmu.c > > > @@ -1685,15 +1685,17 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa, > > > } > > > > > > out_unlock: > > > + if (writable && !ret) > > > + kvm_set_pfn_dirty(pfn); > > > > I'm guessing you meant kvm_release_pfn_dirty() here, because this leaks > > a reference. Doh, I did indeed. Alternatively, this could be: if (writable && !ret) kvm_set_pfn_dirty(pfn); kvm_release_pfn_clean(pfn); It won't matter in the end, because this just becomes: kvm_release_faultin_page(kvm, page, !!ret, writable); So I guess the question is if you prefer to make the switch to an if-else in this path, or more implicitly in the conversion to kvm_release_faultin_page(). I made the same goof for RISC-V, perhaps to prove that I too can copy+paste arm64's MMU code ;-) From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-yw1-f201.google.com (mail-yw1-f201.google.com [209.85.128.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 4EBA714C5A1 for ; Mon, 5 Aug 2024 23:53:03 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.128.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1722901985; cv=none; b=BTo8vPSBVjpVG9Bz+3CdLlqm24cW7aErRNyWtt8vzKdR08r5HNzF9K8zS5SKe9IbAno//QlpB2bHcnXtYw4GxDieb30rMD9zllk9HMf87jVmZdWW1wA1CudL7hQJoP/kOhPyMrTa99AvtBfE/302BtgUaaNOl6I4HSzBrx+v+aA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1722901985; c=relaxed/simple; bh=XE64EO9QsKUjNS+RxiZtVEDU63XJXco52ktIOyCusQg=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; 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charset="us-ascii" On Mon, Aug 05, 2024, Oliver Upton wrote: > > > --- > > > arch/arm64/kvm/mmu.c | 10 ++++++---- > > > 1 file changed, 6 insertions(+), 4 deletions(-) > > > > > > diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c > > > index 22ee37360c4e..ce13c3d884d5 100644 > > > --- a/arch/arm64/kvm/mmu.c > > > +++ b/arch/arm64/kvm/mmu.c > > > @@ -1685,15 +1685,17 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa, > > > } > > > > > > out_unlock: > > > + if (writable && !ret) > > > + kvm_set_pfn_dirty(pfn); > > > > I'm guessing you meant kvm_release_pfn_dirty() here, because this leaks > > a reference. Doh, I did indeed. Alternatively, this could be: if (writable && !ret) kvm_set_pfn_dirty(pfn); kvm_release_pfn_clean(pfn); It won't matter in the end, because this just becomes: kvm_release_faultin_page(kvm, page, !!ret, writable); So I guess the question is if you prefer to make the switch to an if-else in this path, or more implicitly in the conversion to kvm_release_faultin_page(). I made the same goof for RISC-V, perhaps to prove that I too can copy+paste arm64's MMU code ;-) From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id C7FE2C3DA4A for ; Mon, 5 Aug 2024 23:53:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:Cc:To:From:Subject:Message-ID: References:Mime-Version:In-Reply-To:Date:Reply-To:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:List-Owner; bh=kGx3x4au0GkGeUX+csaRQjSvbRtPJkmh8vW3oWNHLdI=; 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charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-riscv" Errors-To: linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org On Mon, Aug 05, 2024, Oliver Upton wrote: > > > --- > > > arch/arm64/kvm/mmu.c | 10 ++++++---- > > > 1 file changed, 6 insertions(+), 4 deletions(-) > > > > > > diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c > > > index 22ee37360c4e..ce13c3d884d5 100644 > > > --- a/arch/arm64/kvm/mmu.c > > > +++ b/arch/arm64/kvm/mmu.c > > > @@ -1685,15 +1685,17 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa, > > > } > > > > > > out_unlock: > > > + if (writable && !ret) > > > + kvm_set_pfn_dirty(pfn); > > > > I'm guessing you meant kvm_release_pfn_dirty() here, because this leaks > > a reference. Doh, I did indeed. Alternatively, this could be: if (writable && !ret) kvm_set_pfn_dirty(pfn); kvm_release_pfn_clean(pfn); It won't matter in the end, because this just becomes: kvm_release_faultin_page(kvm, page, !!ret, writable); So I guess the question is if you prefer to make the switch to an if-else in this path, or more implicitly in the conversion to kvm_release_faultin_page(). I made the same goof for RISC-V, perhaps to prove that I too can copy+paste arm64's MMU code ;-) _______________________________________________ linux-riscv mailing list linux-riscv@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-riscv From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from lists.ozlabs.org (lists.ozlabs.org [112.213.38.117]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 15BF4C3DA7F for ; Mon, 5 Aug 2024 23:53:49 +0000 (UTC) Authentication-Results: lists.ozlabs.org; dkim=fail reason="signature verification failed" (2048-bit key; unprotected) header.d=google.com header.i=@google.com header.a=rsa-sha256 header.s=20230601 header.b=DJJ3dqJK; dkim-atps=neutral Received: from boromir.ozlabs.org (localhost [IPv6:::1]) by lists.ozlabs.org (Postfix) with ESMTP id 4WdCvH51XJz3cYW for ; 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AJvYcCXTlUOQpcod3XEtjTTK6xF0iue8B/W6w9iEJq9+Sj2EzZIabnqkNAq0CX7bZBI1N6EuPwO9OCypeGwf+Y25uYNUw34O6Wuri1DeYIWpBg== X-Gm-Message-State: AOJu0YyIOg58z6aRTvRlt05vZ/Ot/1/OSTUF+X9ACJKtmh8qfiqW+MsC y4QbCz6rXOHMECOLT3eclMO+UNoZKVT0pvd+R6jZNNzVNol9LZTA64DjT1jGNwtHCcw8pBHnTUf eLg== X-Google-Smtp-Source: AGHT+IHjgF0Ca8ethUSfrozdkFUFp0o0AUPtEhLPgrNZWa8lbUZ7qZQp3Z7lR+cNHb6EVM2g/AygpE/k1/Q= X-Received: from zagreus.c.googlers.com ([fda3:e722:ac3:cc00:7f:e700:c0a8:5c37]) (user=seanjc job=sendgmr) by 2002:a05:690c:f16:b0:691:a38c:a61d with SMTP id 00721157ae682-691a39bf26cmr3721507b3.3.1722901982364; Mon, 05 Aug 2024 16:53:02 -0700 (PDT) Date: Mon, 5 Aug 2024 16:53:01 -0700 In-Reply-To: Mime-Version: 1.0 References: <20240726235234.228822-1-seanjc@google.com> <20240726235234.228822-55-seanjc@google.com> Message-ID: Subject: Re: [PATCH v12 54/84] KVM: arm64: Mark "struct page" pfns accessed/dirty before dropping mmu_lock From: Sean Christopherson To: Oliver Upton Content-Type: text/plain; charset="us-ascii" X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: kvm@vger.kernel.org, linux-kernel@vger.kernel.org, David Matlack , linux-riscv@lists.infradead.org, Claudio Imbrenda , Marc Zyngier , Janosch Frank , Huacai Chen , Fuad Tabba , Christian Borntraeger , Albert Ou , Bibo Mao , loongarch@lists.linux.dev, Paul Walmsley , kvmarm@lists.linux.dev, linux-arm-kernel@lists.infradead.org, linux-mips@vger.kernel.org, Palmer Dabbelt , David Stevens , kvm-riscv@lists.infradead.org, Anup Patel , Paolo Bonzini , Tianrui Zhao , linuxppc-dev@lists.ozlabs.org Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" On Mon, Aug 05, 2024, Oliver Upton wrote: > > > --- > > > arch/arm64/kvm/mmu.c | 10 ++++++---- > > > 1 file changed, 6 insertions(+), 4 deletions(-) > > > > > > diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c > > > index 22ee37360c4e..ce13c3d884d5 100644 > > > --- a/arch/arm64/kvm/mmu.c > > > +++ b/arch/arm64/kvm/mmu.c > > > @@ -1685,15 +1685,17 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa, > > > } > > > > > > out_unlock: > > > + if (writable && !ret) > > > + kvm_set_pfn_dirty(pfn); > > > > I'm guessing you meant kvm_release_pfn_dirty() here, because this leaks > > a reference. Doh, I did indeed. Alternatively, this could be: if (writable && !ret) kvm_set_pfn_dirty(pfn); kvm_release_pfn_clean(pfn); It won't matter in the end, because this just becomes: kvm_release_faultin_page(kvm, page, !!ret, writable); So I guess the question is if you prefer to make the switch to an if-else in this path, or more implicitly in the conversion to kvm_release_faultin_page(). I made the same goof for RISC-V, perhaps to prove that I too can copy+paste arm64's MMU code ;-)