From patchwork Sun May 1 22:07:28 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Maciej S. Szmigiero" X-Patchwork-Id: 12833796 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 E375AC433EF for ; Sun, 1 May 2022 22:10:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1377013AbiEAWLl (ORCPT ); Sun, 1 May 2022 18:11:41 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44284 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1355597AbiEAWLi (ORCPT ); Sun, 1 May 2022 18:11:38 -0400 Received: from vps-vb.mhejs.net (vps-vb.mhejs.net [37.28.154.113]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id CC04B26118; Sun, 1 May 2022 15:08:09 -0700 (PDT) Received: from MUA by vps-vb.mhejs.net with esmtps (TLS1.2) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.94.2) (envelope-from ) id 1nlHjX-0008NO-BV; Mon, 02 May 2022 00:08:03 +0200 From: "Maciej S. Szmigiero" To: Paolo Bonzini , Sean Christopherson Cc: Vitaly Kuznetsov , Wanpeng Li , Jim Mattson , Joerg Roedel , Maxim Levitsky , kvm@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v3 04/12] KVM: SVM: Stuff next_rip on emulated INT3 injection if NRIPS is supported Date: Mon, 2 May 2022 00:07:28 +0200 Message-Id: X-Mailer: git-send-email 2.35.1 In-Reply-To: References: MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Sean Christopherson If NRIPS is supported in hardware but disabled in KVM, set next_rip to the next RIP when advancing RIP as part of emulating INT3 injection. There is no flag to tell the CPU that KVM isn't using next_rip, and so leaving next_rip is left as is will result in the CPU pushing garbage onto the stack when vectoring the injected event. Reviewed-by: Maxim Levitsky Fixes: 66b7138f9136 ("KVM: SVM: Emulate nRIP feature when reinjecting INT3") Signed-off-by: Sean Christopherson Signed-off-by: Maciej S. Szmigiero --- arch/x86/kvm/svm/svm.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c index 1a719f47a964..a05a4e521400 100644 --- a/arch/x86/kvm/svm/svm.c +++ b/arch/x86/kvm/svm/svm.c @@ -392,6 +392,10 @@ static void svm_queue_exception(struct kvm_vcpu *vcpu) */ (void)svm_skip_emulated_instruction(vcpu); rip = kvm_rip_read(vcpu); + + if (boot_cpu_has(X86_FEATURE_NRIPS)) + svm->vmcb->control.next_rip = rip; + svm->int3_rip = rip + svm->vmcb->save.cs.base; svm->int3_injected = rip - old_rip; } @@ -3701,7 +3705,7 @@ static void svm_complete_interrupts(struct kvm_vcpu *vcpu) /* * If NextRIP isn't enabled, KVM must manually advance RIP prior to * injecting the soft exception/interrupt. That advancement needs to - * be unwound if vectoring didn't complete. Note, the _new_ event may + * be unwound if vectoring didn't complete. Note, the new event may * not be the injected event, e.g. if KVM injected an INTn, the INTn * hit a #NP in the guest, and the #NP encountered a #PF, the #NP will * be the reported vectored event, but RIP still needs to be unwound.