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AKwUvBxCItRU3BKZOJ4rIy8kxgwDE0sbyZJZcHnFu6lRmj44t4zMlYrCpfaxqsqQhupi8WhxRVnSCNB75s32@lists.linux.dev X-Gm-Message-State: AFuF++myaac/LI4EeLdZPSWJpbVbIfNUMops1XLr+whWIJtuo0Z4qaQ1 GyjWxIK17xiOrcUiRTgFkziBE1K/wG6nw8m+TTFxDI7aP5v8IinoQkHxG7MHfVb9T0l97tbGKt8 aKZ8sdg== X-Received: from pgbcw4.prod.google.com ([2002:a05:6a02:4284:b0:cc7:b387:6d4b]) (user=seanjc job=prod-delivery.src-stubby-dispatcher) by 2002:a05:6a20:7fa5:b0:3de:849f:9053 with SMTP id adf61e73a8af0-3de9530b969mr741880637.45.1790729712492; Tue, 29 Sep 2026 17:55:12 -0700 (PDT) Date: Tue, 29 Sep 2026 17:55:11 -0700 In-Reply-To: <3c0ee89f560b0235f293b32019327186785aa795.camel@intel.com> Precedence: bulk X-Mailing-List: linux-coco@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20260930001127.3170009-1-seanjc@google.com> <3c0ee89f560b0235f293b32019327186785aa795.camel@intel.com> Message-ID: Subject: Re: [PATCH v2 0/3] KVM: TDX: Syntehsize SHUTDOWN on unhandled EPT Violation From: Sean Christopherson To: Rick P Edgecombe Cc: "pbonzini@redhat.com" , "kas@kernel.org" , "jthoughton@google.com" , "dave.hansen@linux.intel.com" , "x86@kernel.org" , "binbin.wu@linux.intel.com" , Xiaoyao Li , "linux-kernel@vger.kernel.org" , Yan Y Zhao , "sashiko-bot@kernel.org" , "kvm@vger.kernel.org" , "linux-coco@lists.linux.dev" , "ackerleytng@google.com" , Vishal Annapurve Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable On Wed, Sep 30, 2026, Rick P Edgecombe wrote: > On Tue, 2026-09-29 at 17:11 -0700, Sean Christopherson wrote: > > Signal SHUTDOWN instead of -EIO if the guest accesses an unaccepted pag= e and > > has disabled EPT Violation #VEs on such accesses.=C2=A0 Returning -EIO = is all but > > guaranteed to mislead the VMM into thinking KVM (or the VMM) messed up,= and > > will likely result in the VM being terminated instead of rebooted. >=20 > I'm pretty sure Yan had a test for this path, and I'd love to see it actu= ally > exercised. What is the urgency on getting this fix upstream? Can we wait = a week? Absolutely. It can probably wait a month and no one would care. IIRC, thi= s got hit by someone (internal to Google) deliberately crashing a guest kernel an= d doing funky things with kexec. It showed up on my radar purely because our autom= ated madness alerted on the resulting assertion (on -EIO) in the VMM.