From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 8DA97BA44 for ; Tue, 7 Mar 2023 17:50:30 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id E920BC433D2; Tue, 7 Mar 2023 17:50:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1678211430; bh=LHBUekxiZsO/KNw8HvEnInJHDZhQ4nN6HtA2I1XcErw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ZFKQI9OZhsS1gyCNkz9Jv2wvr9QreqXgrxas4zitJdvRiIlj28Ln/8zDChnXY0InH pFADt2YyE0h/VR5baIJVSGTTavlbopmpKWkLcfDil01BkngNRGb6Q1gViZM7Vf9oxo 5vXOLgPLEU1gvE/MhWVF6B0ZeangJNYgz7MJlV5g= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Paolo Bonzini , Sean Christopherson , Maxim Levitsky Subject: [PATCH 6.2 0828/1001] KVM: SVM: Flush the "current" TLB when activating AVIC Date: Tue, 7 Mar 2023 18:00:00 +0100 Message-Id: <20230307170057.700953747@linuxfoundation.org> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20230307170022.094103862@linuxfoundation.org> References: <20230307170022.094103862@linuxfoundation.org> User-Agent: quilt/0.67 Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: Sean Christopherson commit 0ccf3e7cb95a2db8ddb2a44812037ffba8166dc9 upstream. Flush the TLB when activating AVIC as the CPU can insert into the TLB while AVIC is "locally" disabled. KVM doesn't treat "APIC hardware disabled" as VM-wide AVIC inhibition, and so when a vCPU has its APIC hardware disabled, AVIC is not guaranteed to be inhibited. As a result, KVM may create a valid NPT mapping for the APIC base, which the CPU can cache as a non-AVIC translation. Note, Intel handles this in vmx_set_virtual_apic_mode(). Reviewed-by: Paolo Bonzini Cc: stable@vger.kernel.org Signed-off-by: Sean Christopherson Reviewed-by: Maxim Levitsky Message-Id: <20230106011306.85230-4-seanjc@google.com> Signed-off-by: Paolo Bonzini Signed-off-by: Greg Kroah-Hartman --- arch/x86/kvm/svm/avic.c | 6 ++++++ 1 file changed, 6 insertions(+) --- a/arch/x86/kvm/svm/avic.c +++ b/arch/x86/kvm/svm/avic.c @@ -86,6 +86,12 @@ static void avic_activate_vmcb(struct vc /* Disabling MSR intercept for x2APIC registers */ svm_set_x2apic_msr_interception(svm, false); } else { + /* + * Flush the TLB, the guest may have inserted a non-APIC + * mapping into the TLB while AVIC was disabled. + */ + kvm_make_request(KVM_REQ_TLB_FLUSH_CURRENT, &svm->vcpu); + /* For xAVIC and hybrid-xAVIC modes */ vmcb->control.avic_physical_id |= AVIC_MAX_PHYSICAL_ID; /* Enabling MSR intercept for x2APIC registers */