From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id E5A49C433F5 for ; Sat, 29 Jan 2022 12:53:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1350441AbiA2Mxp (ORCPT ); Sat, 29 Jan 2022 07:53:45 -0500 Received: from ams.source.kernel.org ([145.40.68.75]:60052 "EHLO ams.source.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1350355AbiA2Mxp (ORCPT ); Sat, 29 Jan 2022 07:53:45 -0500 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 687C0B827B2 for ; Sat, 29 Jan 2022 12:53:44 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9AF83C340E5; Sat, 29 Jan 2022 12:53:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1643460823; bh=NBZMW4b2m3/byqYxnmMB/PxOoI/itiD3rGlNx0C1v1Q=; h=Subject:To:Cc:From:Date:From; b=GYVFmN5Mxc44RsiFBJU1N2yO5rvCupNJP4xg6vDQ3pIv7ucyUyDdD7QPTTTtp3TO3 AxVoeWlCvaeMDeCIqlITfFVcNv8qhDMms3E2KlM/xw2ccRZS1xf5iY/eXBWm0t3Htl 6C6wIipTLoOSUwQgIMYLdq4MMKHbibQGpAH4vmLg= Subject: FAILED: patch "[PATCH] KVM: SVM: Don't intercept #GP for SEV guests" failed to apply to 5.4-stable tree To: seanjc@google.com, brijesh.singh@amd.com, liam.merwick@oracle.com, pbonzini@redhat.com, thomas.lendacky@amd.com Cc: From: Date: Sat, 29 Jan 2022 13:53:32 +0100 Message-ID: <1643460812160107@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org The patch below does not apply to the 5.4-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to . thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From 0b0be065b7563ac708aaa9f69dd4941c80b3446d Mon Sep 17 00:00:00 2001 From: Sean Christopherson Date: Thu, 20 Jan 2022 01:07:13 +0000 Subject: [PATCH] KVM: SVM: Don't intercept #GP for SEV guests Never intercept #GP for SEV guests as reading SEV guest private memory will return cyphertext, i.e. emulating on #GP can't work as intended. Cc: stable@vger.kernel.org Cc: Tom Lendacky Cc: Brijesh Singh Signed-off-by: Sean Christopherson Reviewed-by: Liam Merwick Message-Id: <20220120010719.711476-4-seanjc@google.com> Signed-off-by: Paolo Bonzini diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c index 37eb3168e0ea..defc91a8c04c 100644 --- a/arch/x86/kvm/svm/svm.c +++ b/arch/x86/kvm/svm/svm.c @@ -312,7 +312,11 @@ int svm_set_efer(struct kvm_vcpu *vcpu, u64 efer) return ret; } - if (svm_gp_erratum_intercept) + /* + * Never intercept #GP for SEV guests, KVM can't + * decrypt guest memory to workaround the erratum. + */ + if (svm_gp_erratum_intercept && !sev_guest(vcpu->kvm)) set_exception_intercept(svm, GP_VECTOR); } } @@ -1010,9 +1014,10 @@ static void init_vmcb(struct kvm_vcpu *vcpu) * Guest access to VMware backdoor ports could legitimately * trigger #GP because of TSS I/O permission bitmap. * We intercept those #GP and allow access to them anyway - * as VMware does. + * as VMware does. Don't intercept #GP for SEV guests as KVM can't + * decrypt guest memory to decode the faulting instruction. */ - if (enable_vmware_backdoor) + if (enable_vmware_backdoor && !sev_guest(vcpu->kvm)) set_exception_intercept(svm, GP_VECTOR); svm_set_intercept(svm, INTERCEPT_INTR);