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AJvYcCWYL34SD3Wo1ABAAmQ5HQtGFzQ74rcq4AznjHva/R1dUlUb+G1+MzEPC/psC5rAaYB7pOI=@vger.kernel.org X-Gm-Message-State: AOJu0YwOYK53VllVsfNaAYtvK/+GZTU6nnoB3jFYFsJIHK47ePxeG6e6 Jvj/YkDcMflz0PP7zEY5mrKKGjiXN7q3an2wMxkyU46pljb0tXY2/biNF2Fguejkm4tG1m4A2il znQ== X-Google-Smtp-Source: AGHT+IHz/sqxbIaZMzAhwQE+KHAQ50pc4vGOx7OQ/MlEMfrpYKQ16K4ySzEgLcCV5+myw9EmSbX31Z6uvf4= X-Received: from zagreus.c.googlers.com ([fda3:e722:ac3:cc00:9d:3983:ac13:c240]) (user=seanjc job=sendgmr) by 2002:a17:90a:e147:b0:2d8:a9c2:2f3a with SMTP id 98e67ed59e1d1-2e5616d8f42mr22750a91.3.1729534130899; Mon, 21 Oct 2024 11:08:50 -0700 (PDT) Date: Mon, 21 Oct 2024 11:08:49 -0700 In-Reply-To: Precedence: bulk X-Mailing-List: kvm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20241010182427.1434605-1-seanjc@google.com> <20241010182427.1434605-20-seanjc@google.com> Message-ID: Subject: Re: [PATCH v13 19/85] KVM: Introduce kvm_follow_pfn() to eventually replace "gfn_to_pfn" APIs From: Sean Christopherson To: Yan Zhao Cc: Paolo Bonzini , Marc Zyngier , Oliver Upton , Tianrui Zhao , Bibo Mao , Huacai Chen , Michael Ellerman , Anup Patel , Paul Walmsley , Palmer Dabbelt , Albert Ou , Christian Borntraeger , Janosch Frank , Claudio Imbrenda , kvm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev, loongarch@lists.linux.dev, linux-mips@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, kvm-riscv@lists.infradead.org, linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org, "Alex =?utf-8?Q?Benn=C3=A9e?=" , David Matlack , David Stevens , Andrew Jones Content-Type: text/plain; charset="us-ascii" On Mon, Oct 21, 2024, Yan Zhao wrote: > On Thu, Oct 10, 2024 at 11:23:21AM -0700, Sean Christopherson wrote: > > --- a/virt/kvm/pfncache.c > > +++ b/virt/kvm/pfncache.c > > @@ -159,6 +159,12 @@ static kvm_pfn_t hva_to_pfn_retry(struct gfn_to_pfn_cache *gpc) > > kvm_pfn_t new_pfn = KVM_PFN_ERR_FAULT; > > void *new_khva = NULL; > > unsigned long mmu_seq; > > + struct kvm_follow_pfn kfp = { > > + .slot = gpc->memslot, > > + .gfn = gpa_to_gfn(gpc->gpa), > > + .flags = FOLL_WRITE, > > + .hva = gpc->uhva, > > + }; > Is .map_writable uninitialized? Nope, per C99, "subobjects without explicit initializers are initialized to zero", i.e. map_writable is initialized to "false".