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 46505C19F2C for ; Wed, 3 Aug 2022 19:27:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236096AbiHCT1H (ORCPT ); Wed, 3 Aug 2022 15:27:07 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60074 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236148AbiHCT1F (ORCPT ); Wed, 3 Aug 2022 15:27:05 -0400 Received: from mail-pg1-x54a.google.com (mail-pg1-x54a.google.com [IPv6:2607:f8b0:4864:20::54a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id F1895564E5 for ; Wed, 3 Aug 2022 12:27:04 -0700 (PDT) Received: by mail-pg1-x54a.google.com with SMTP id f128-20020a636a86000000b0041a4b07b039so7105163pgc.5 for ; Wed, 03 Aug 2022 12:27:04 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=cc:to:from:subject:references:mime-version:message-id:in-reply-to :date:reply-to:from:to:cc; bh=nm7CFbOdnKtZDNkgkKBzXQSPp+dIl3jdjLzC+jO16zk=; b=UJ2itWk2ezkIYRhnzAmzoIQO8u9ey77vKkdIhOd9vs8Zeh71OH2Ir0xFAgTl5ekOdQ zg4kSUzcMulV8zPGAmflfEkY8hdvqVxKfwgo3tN6kvzJ7cctBjo+NdAb+qPg81Z31eH1 2k8GX3GntwsZ70h5FT00xRMSJlk7Ms902eCR6sQsk14inYSRrJn4PoHnxsJ6cCx+xWx6 A8tH6ERH0TGgjMT6bjFklvTFBR5/PHNbdqm1O3lq8/lEI/G+5r7PEnb2vhv19udY9ok7 V9hse3EWlAzb3IF2d7b2PyMdFA8w2Bj/vQj3EZzWcyi0aZAb+hIdq1wBC6EoFxSHijIr b9Mw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=cc:to:from:subject:references:mime-version:message-id:in-reply-to :date:reply-to:x-gm-message-state:from:to:cc; bh=nm7CFbOdnKtZDNkgkKBzXQSPp+dIl3jdjLzC+jO16zk=; b=Q6fiEQwSF/CLbrfy2CdAcKMdSFhGSWHdLOgtdTZNBIMnWAlzjZ9cmVw3vj9b8kVaTe CUwRKB8PwQx+d/oJRhmMT1FHWMNLpZPRSbQbWwD0dqjNTjsJe6BQ5WY/RQx8gcR8Awjz ekN5O27wyT6QMg+ssN7Njh5GM+jvnAEklbuwHxGNXLUoGtCfKd6LhQMUt8Z7e0agJ6eN bzGYu+d9KsdWmOt90pXeapiC3gO5WfarW5O5/zRIAXeXxQgWcZXIp99d9NWwcMq2VGqV YBC0VCVXyjmqYXNh4YSkxmpvtNTzxeVJug7MLVWNuY6vMqyNyzbnhux0k8r8eJacnyQm ZOYQ== X-Gm-Message-State: AJIora9b735iynh+NOYQVYgGI2dPy6E6zMZzi/DUTUqPN4bxW2qyAwXh Hjw5VayxO/SUAQMt0qbxJR4BFyJGy3Q= X-Google-Smtp-Source: AGRyM1smK3BViI7TxhEbyAjRfforzWrdjCXIGbu9LuouDuELMs/W7f0KHUYaF4H+R7SWS+UD94l95eGoDe8= X-Received: from zagreus.c.googlers.com ([fda3:e722:ac3:cc00:7f:e700:c0a8:5c37]) (user=seanjc job=sendgmr) by 2002:a63:e258:0:b0:41a:d92b:64f9 with SMTP id y24-20020a63e258000000b0041ad92b64f9mr21846257pgj.148.1659554824574; Wed, 03 Aug 2022 12:27:04 -0700 (PDT) Reply-To: Sean Christopherson Date: Wed, 3 Aug 2022 19:26:52 +0000 In-Reply-To: <20220803192658.860033-1-seanjc@google.com> Message-Id: <20220803192658.860033-2-seanjc@google.com> Mime-Version: 1.0 References: <20220803192658.860033-1-seanjc@google.com> X-Mailer: git-send-email 2.37.1.559.g78731f0fdb-goog Subject: [PATCH v2 1/7] KVM: x86: Refresh PMU after writes to MSR_IA32_PERF_CAPABILITIES From: Sean Christopherson To: Peter Zijlstra , Ingo Molnar , Arnaldo Carvalho de Melo , Sean Christopherson , Paolo Bonzini Cc: Mark Rutland , Alexander Shishkin , Jiri Olsa , Namhyung Kim , linux-perf-users@vger.kernel.org, linux-kernel@vger.kernel.org, kvm@vger.kernel.org, Like Xu Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-perf-users@vger.kernel.org Refresh the PMU if userspace modifies MSR_IA32_PERF_CAPABILITIES. KVM consumes the vCPU's PERF_CAPABILITIES when enumerating PEBS support, but relies on CPUID updates to refresh the PMU. I.e. KVM will do the wrong thing if userspace stuffs PERF_CAPABILITIES _after_ setting guest CPUID. Note, KVM may do the "wrong" thing if userspace changes PERF_CAPABILITIES after running the vCPU, i.e. after KVM_RUN. Similar to disallowing CPUID changes after KVM_RUN, KVM should also disallow changing feature MSRs after KVM_RUN to prevent unexpected behavior. That problem will be addressed separately at it affects MSRs other than PERF_CAPABILITES. Opportunistically fix a curly-brace indentation. Fixes: c59a1f106f5c ("KVM: x86/pmu: Add IA32_PEBS_ENABLE MSR emulation for extended PEBS") Cc: Like Xu Signed-off-by: Sean Christopherson --- arch/x86/kvm/x86.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 33560bfa0cac..dc19298e7150 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -3546,9 +3546,9 @@ int kvm_set_msr_common(struct kvm_vcpu *vcpu, struct msr_data *msr_info) return 1; vcpu->arch.perf_capabilities = data; - + kvm_pmu_refresh(vcpu); return 0; - } + } case MSR_EFER: return set_efer(vcpu, msr_info); case MSR_K7_HWCR: -- 2.37.1.559.g78731f0fdb-goog