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 X-Spam-Level: X-Spam-Status: No, score=-8.6 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id ADED5C43613 for ; Thu, 20 Jun 2019 12:13:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 88A062082C for ; Thu, 20 Jun 2019 12:13:42 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="E3VyLGyX" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731724AbfFTMNi (ORCPT ); Thu, 20 Jun 2019 08:13:38 -0400 Received: from mail-wr1-f66.google.com ([209.85.221.66]:34603 "EHLO mail-wr1-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726874AbfFTMNi (ORCPT ); Thu, 20 Jun 2019 08:13:38 -0400 Received: by mail-wr1-f66.google.com with SMTP id k11so2819487wrl.1; Thu, 20 Jun 2019 05:13:36 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=sender:from:to:subject:date:message-id; bh=b6QfbK+zg+CntQ2YnFA9EsYYsbhSbAKbyatBLLsVS6o=; b=E3VyLGyXBRciniccq2xfnnDJ3KEBTKwNxEIMDG8aeHSgCgrA4l/llxQuU9bNLgJ4IU yBXGW13NFJS0AXY5AxC1J8UHqWdwXuqSK2EE0yj6CG23qHonx/8WatFfAJLzMjWuOGjb O01hXtoIH8HBiEJ071hcaelr/8phQA6qymOmggqs5BRxSGPDhoOt8UwBf9pm99jnKMh5 LPq7FoEG0F8vsrHTr0+t8uZhENtc+IQH1EKdXgYywN865fOETmu0IEv/ez+L8z4hgIDv np9aaSgdBDPuGJ0UmFmCBxT+nr9/cOk+QeNpUsa8ZTCsIAsVyfBvIgJ5ug7k7wlSvKFI SYHg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:from:to:subject:date:message-id; bh=b6QfbK+zg+CntQ2YnFA9EsYYsbhSbAKbyatBLLsVS6o=; b=l/EeKOMcsZz7Tx1ixy7YrStqsb6aAgNNDqPtpFEJEvHqxXUh5K8G2QdXGskoNmDH5G SJivsnyY+l4fGInCOiBZAzk8N9evJPtuDIg9IMxIQ8F5DjLwX2g7teF5l7cI7Q/qi2Xj bf+cIqaS/Al+CYGdMOiDynvhc6uTkRXRdbe/Z3aEtMefSx7G6/hejiJJJmfwKevVqJKM h7BBurB+Q8QNnEj3sobCx+CBnp1lLf7ROniwKa6sx3g2V50qcu032nuF2MbzSNUcyoE5 IQogq4UBDTxvDRKCb+7/hBIScX+fd9FNvgIZ8CYHwJx/RDFCCnXCkCIVyoT0YzvTXtC1 DoMg== X-Gm-Message-State: APjAAAWt8YolQIoLOboLnOWi2d7S52L/AKpsTNBOnAdC4AsnPBSYJVar xfBKaqK+nh0ltK1u3o5Ti5ysDYIH X-Google-Smtp-Source: APXvYqz8eIsNCFktOotZ5v5T4ToB/P2JaF1GzsBr9KUGro69jplOWK8feo66DzLVbIhqZJaoccIdAw== X-Received: by 2002:adf:ed41:: with SMTP id u1mr44066764wro.162.1561032815742; Thu, 20 Jun 2019 05:13:35 -0700 (PDT) Received: from 640k.lan ([93.56.166.5]) by smtp.gmail.com with ESMTPSA id j4sm16720548wrx.57.2019.06.20.05.13.34 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 20 Jun 2019 05:13:35 -0700 (PDT) From: Paolo Bonzini To: linux-kernel@vger.kernel.org, kvm@vger.kernel.org Subject: [PATCH] KVM: svm: add nrips module parameter Date: Thu, 20 Jun 2019 14:13:33 +0200 Message-Id: <1561032813-16698-1-git-send-email-pbonzini@redhat.com> X-Mailer: git-send-email 1.8.3.1 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org Allow testing code for old processors that lack the next RIP save feature, by disabling usage of the next_rip field. Nested hypervisors however get the feature unconditionally. Signed-off-by: Paolo Bonzini --- arch/x86/kvm/svm.c | 15 ++++++++++++--- 1 file changed, 12 insertions(+), 3 deletions(-) diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c index 735b8c01895e..fe046c13f03b 100644 --- a/arch/x86/kvm/svm.c +++ b/arch/x86/kvm/svm.c @@ -367,6 +367,10 @@ struct amd_svm_iommu_ir { module_param(avic, int, S_IRUGO); #endif +/* enable/disable Next RIP Save */ +static int nrips = true; +module_param(nrips, int, 0444); + /* enable/disable Virtual VMLOAD VMSAVE */ static int vls = true; module_param(vls, int, 0444); @@ -773,7 +777,7 @@ static void skip_emulated_instruction(struct kvm_vcpu *vcpu) { struct vcpu_svm *svm = to_svm(vcpu); - if (svm->vmcb->control.next_rip != 0) { + if (nrips && svm->vmcb->control.next_rip != 0) { WARN_ON_ONCE(!static_cpu_has(X86_FEATURE_NRIPS)); svm->next_rip = svm->vmcb->control.next_rip; } @@ -810,7 +814,7 @@ static void svm_queue_exception(struct kvm_vcpu *vcpu) kvm_deliver_exception_payload(&svm->vcpu); - if (nr == BP_VECTOR && !static_cpu_has(X86_FEATURE_NRIPS)) { + if (nr == BP_VECTOR && !nrips) { unsigned long rip, old_rip = kvm_rip_read(&svm->vcpu); /* @@ -1367,6 +1371,11 @@ static __init int svm_hardware_setup(void) } else kvm_disable_tdp(); + if (nrips) { + if (!boot_cpu_has(X86_FEATURE_NRIPS)) + nrips = false; + } + if (avic) { if (!npt_enabled || !boot_cpu_has(X86_FEATURE_AVIC) || @@ -3938,7 +3947,7 @@ static int rdpmc_interception(struct vcpu_svm *svm) { int err; - if (!static_cpu_has(X86_FEATURE_NRIPS)) + if (!nrips) return emulate_on_interception(svm); err = kvm_rdpmc(&svm->vcpu); -- 1.8.3.1