From patchwork Wed Jan 29 23:46:17 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sean Christopherson X-Patchwork-Id: 11357109 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 05ABA13A4 for ; Wed, 29 Jan 2020 23:48:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E1960206F0 for ; Wed, 29 Jan 2020 23:48:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727236AbgA2Xsb (ORCPT ); Wed, 29 Jan 2020 18:48:31 -0500 Received: from mga06.intel.com ([134.134.136.31]:46690 "EHLO mga06.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727086AbgA2Xqq (ORCPT ); Wed, 29 Jan 2020 18:46:46 -0500 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga001.jf.intel.com ([10.7.209.18]) by orsmga104.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 29 Jan 2020 15:46:43 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.70,379,1574150400"; d="scan'208";a="309551700" Received: from sjchrist-coffee.jf.intel.com ([10.54.74.202]) by orsmga001.jf.intel.com with ESMTP; 29 Jan 2020 15:46:43 -0800 From: Sean Christopherson To: Paolo Bonzini Cc: Sean Christopherson , Vitaly Kuznetsov , Wanpeng Li , Jim Mattson , Joerg Roedel , kvm@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH 03/26] KVM: x86: Snapshot MSR index in a local variable when processing lists Date: Wed, 29 Jan 2020 15:46:17 -0800 Message-Id: <20200129234640.8147-4-sean.j.christopherson@intel.com> X-Mailer: git-send-email 2.24.1 In-Reply-To: <20200129234640.8147-1-sean.j.christopherson@intel.com> References: <20200129234640.8147-1-sean.j.christopherson@intel.com> MIME-Version: 1.0 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org Snapshot the MSR index when processing the virtualized and emulated MSR lists in kvm_init_msr_list() to improve code readability, particularly in the RTIT and PerfMon MSR checks. No functional change intended. Signed-off-by: Sean Christopherson Reviewed-by: Vitaly Kuznetsov --- arch/x86/kvm/x86.c | 22 +++++++++++++--------- 1 file changed, 13 insertions(+), 9 deletions(-) diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 24597526b5de..3d4a5326d84e 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -5214,7 +5214,7 @@ long kvm_arch_vm_ioctl(struct file *filp, static void kvm_init_msr_list(void) { struct x86_pmu_capability x86_pmu; - u32 dummy[2]; + u32 dummy[2], msr_index; unsigned i; BUILD_BUG_ON_MSG(INTEL_PMC_MAX_FIXED != 4, @@ -5227,14 +5227,16 @@ static void kvm_init_msr_list(void) num_msr_based_features = 0; for (i = 0; i < ARRAY_SIZE(msrs_to_save_all); i++) { - if (rdmsr_safe(msrs_to_save_all[i], &dummy[0], &dummy[1]) < 0) + msr_index = msrs_to_save_all[i]; + + if (rdmsr_safe(msr_index, &dummy[0], &dummy[1]) < 0) continue; /* * Even MSRs that are valid in the host may not be exposed * to the guests in some cases. */ - switch (msrs_to_save_all[i]) { + switch (msr_index) { case MSR_IA32_BNDCFGS: if (!kvm_mpx_supported()) continue; @@ -5262,17 +5264,17 @@ static void kvm_init_msr_list(void) break; case MSR_IA32_RTIT_ADDR0_A ... MSR_IA32_RTIT_ADDR3_B: if (!kvm_x86_ops->pt_supported() || - msrs_to_save_all[i] - MSR_IA32_RTIT_ADDR0_A >= + msr_index - MSR_IA32_RTIT_ADDR0_A >= intel_pt_validate_hw_cap(PT_CAP_num_address_ranges) * 2) continue; break; case MSR_ARCH_PERFMON_PERFCTR0 ... MSR_ARCH_PERFMON_PERFCTR0 + 17: - if (msrs_to_save_all[i] - MSR_ARCH_PERFMON_PERFCTR0 >= + if (msr_index - MSR_ARCH_PERFMON_PERFCTR0 >= min(INTEL_PMC_MAX_GENERIC, x86_pmu.num_counters_gp)) continue; break; case MSR_ARCH_PERFMON_EVENTSEL0 ... MSR_ARCH_PERFMON_EVENTSEL0 + 17: - if (msrs_to_save_all[i] - MSR_ARCH_PERFMON_EVENTSEL0 >= + if (msr_index - MSR_ARCH_PERFMON_EVENTSEL0 >= min(INTEL_PMC_MAX_GENERIC, x86_pmu.num_counters_gp)) continue; break; @@ -5280,14 +5282,16 @@ static void kvm_init_msr_list(void) break; } - msrs_to_save[num_msrs_to_save++] = msrs_to_save_all[i]; + msrs_to_save[num_msrs_to_save++] = msr_index; } for (i = 0; i < ARRAY_SIZE(emulated_msrs_all); i++) { - if (!kvm_x86_ops->has_emulated_msr(emulated_msrs_all[i])) + msr_index = emulated_msrs_all[i]; + + if (!kvm_x86_ops->has_emulated_msr(msr_index)) continue; - emulated_msrs[num_emulated_msrs++] = emulated_msrs_all[i]; + emulated_msrs[num_emulated_msrs++] = msr_index; } for (i = 0; i < ARRAY_SIZE(msr_based_features_all); i++) {