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AJvYcCVQ3KEpvT/vRCYZHTDDFd2T6XpMB4/ePwOTViQL9jk+J9FAnj3NNMBi5tmDMDEPwRcVkTPkjAsYaTQayGA=@vger.kernel.org X-Gm-Message-State: AOJu0YzqQYM54Gm8JKtjjoHNmX3SfYXW3/iWFTLA5tx0fME/FV0zVPLy MPfrsBOmDAJ9NhNb98ufgWWUDy74/cdvsLmkoSM36RHOpPiVfMif4vRxJGcFKoVJNuBSJCOOCER 1doTOkg== X-Google-Smtp-Source: AGHT+IEVTUFFWM+7ReoOwe5q9bU7aGMuWtAYW9EM8tyJI0p++Z5ywj3KuSfop6I7e3jDpuwYECcsURxtmbU= X-Received: from plkk15.prod.google.com ([2002:a17:902:c40f:b0:234:9673:1d13]) (user=seanjc job=prod-delivery.src-stubby-dispatcher) by 2002:a17:902:ef52:b0:236:6e4f:d439 with SMTP id d9443c01a7336-23823ff236emr7903665ad.23.1750794119123; Tue, 24 Jun 2025 12:41:59 -0700 (PDT) Date: Tue, 24 Jun 2025 12:38:36 -0700 In-Reply-To: <20250602234851.54573-1-seanjc@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20250602234851.54573-1-seanjc@google.com> X-Mailer: git-send-email 2.50.0.714.g196bf9f422-goog Message-ID: <175079322774.520923.14554474229751214016.b4-ty@google.com> Subject: Re: [PATCH] KVM: x86/mmu: Exempt nested EPT page tables from !USER, CR0.WP=0 logic From: Sean Christopherson To: Sean Christopherson , Paolo Bonzini Cc: kvm@vger.kernel.org, linux-kernel@vger.kernel.org, Jon Kohler , Sergey Dyasli Content-Type: text/plain; charset="utf-8" On Mon, 02 Jun 2025 16:48:51 -0700, Sean Christopherson wrote: > Exempt nested EPT shadow pages tables from the CR0.WP=0 handling of > supervisor writes, as EPT doesn't have a U/S bit and isn't affected by > CR0.WP (or CR4.SMEP in the exception to the exception). > > Opportunistically refresh the comment to explain what KVM is doing, as > the only record of why KVM shoves in WRITE and drops USER is buried in > years-old changelogs. > > [...] Applied to kvm-x86 mmu, thanks! [1/1] KVM: x86/mmu: Exempt nested EPT page tables from !USER, CR0.WP=0 logic https://github.com/kvm-x86/linux/commit/ffced8922050 -- https://github.com/kvm-x86/kvm-unit-tests/tree/next