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Wed, 24 Jun 2026 02:32:58 -0700 (PDT) Received: from [192.168.10.48] ([151.95.156.160]) by smtp.gmail.com with ESMTPSA id ffacd0b85a97d-46c1e840eefsm5788075f8f.1.2026.06.24.02.32.57 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 24 Jun 2026 02:32:58 -0700 (PDT) From: Paolo Bonzini To: Sean Christopherson Cc: kvm@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] KVM: x86/mmu: Bug the VM, not the host kernel, if KVM write-protects upper SPTEs Date: Wed, 24 Jun 2026 11:28:04 +0200 Message-ID: <20260624092803.972646-2-pbonzini@redhat.com> X-Mailer: git-send-email 2.54.0 In-Reply-To: <20260618185641.2022368-1-seanjc@google.com> References: Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Queued, thanks. I adjusted the commit message to include Kai's ovservation: Instead of bugging the host kernel, WARN and terminate the VM if KVM attempts to write-protect at a level that cannot use leaf SPTEs. There is no reason to bring down the entire host; even terminating the VM is likely overkill, but in theory a missed write could corrupt guest memory, so play it safe. Paolo