From patchwork Wed Jul 13 12:25:02 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Like Xu X-Patchwork-Id: 12916642 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 C1E94C43334 for ; Wed, 13 Jul 2022 12:25:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236397AbiGMMZn (ORCPT ); Wed, 13 Jul 2022 08:25:43 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43396 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236373AbiGMMZg (ORCPT ); Wed, 13 Jul 2022 08:25:36 -0400 Received: from mail-pg1-x529.google.com (mail-pg1-x529.google.com [IPv6:2607:f8b0:4864:20::529]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4C8D8C1FED; Wed, 13 Jul 2022 05:25:34 -0700 (PDT) Received: by mail-pg1-x529.google.com with SMTP id 73so10270312pgb.10; Wed, 13 Jul 2022 05:25:34 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=LXqovdDSl/MXsNZWjftmy81y+mPSnXdzim3KrCIDlE0=; b=LLUGPEi/RmbpZwk9P9m5HPEB9sm6XJcxnSoyd8dxAk1RNNLJ4kiniTUwgPSb0SOGsM kP+pNwDVu/sTpyz6I3D/+OMo6wkcGTfbDIRFNQ691ukX50uy0TldoRp8f4t0i9vvxOzH 80ChLc51D1OvQtifYaQiYdhlY71ZzVH4iI0PPvhDUdqEMt49vaXvOzPsk+nlGDBD8GEe SJmwD0W3bG9akHMxtA7QQzlCpwE4MGD2Z64Xa527qvNuflNkm74pUzI7MYDf0YeXcycX 6Yw8pLPAeUttos0Pqjkze0stGX3eqjEUcqHG3fv//3b6A5eCuYtiOmloxFrTqD6Z+69U S9nA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=LXqovdDSl/MXsNZWjftmy81y+mPSnXdzim3KrCIDlE0=; b=HOVViA/Y5RW1/ssLS2ONKdAJwYxQR4Wr+sGQNogb8Z3xOtfLg5u63pvB4JENer/qDN 7ZbPkPsBvNFf8wgzM54BFRDwFIB10sqb5BfRSuvktUzSz/+WcyHgHZ2NqbB3xgsKO8L+ PJBw7ydjr5rS2ErUtC1kyfedoc/kLtytcoLFQErYFWpkNw0mZ4FgxfUOAe7FC9IPpnlg VEk/IYPa9sg29ZbVsXK2IhxQ2GiBKB4BxHhMr/DzqYTqgsgk/OKYuKgTyrKIIdB0d/91 9eXL0aUVSwnkZF8kyXrQ4bxgMweNdXWxrNm60/iu0RCmemuBMv77+cyDdK9kuVaHnjh1 Z9JQ== X-Gm-Message-State: AJIora+G6OsmxC3mUktNwv5byABEqLj8osQqo+4KK2NnKiRjBPY0ZDpX M0KY3MoZ/5qKGQDgRWNcUIc= X-Google-Smtp-Source: AGRyM1sk8JQ44ful7LGxlOnlp8i/NXsMnI/Tct++/5RfdnANJujj/ifyPCW1uswJ2UUvzKZRMWYw3w== X-Received: by 2002:a63:df49:0:b0:412:58fe:2332 with SMTP id h9-20020a63df49000000b0041258fe2332mr2603882pgj.505.1657715134057; Wed, 13 Jul 2022 05:25:34 -0700 (PDT) Received: from localhost.localdomain ([103.7.29.32]) by smtp.gmail.com with ESMTPSA id m7-20020a170902bb8700b0016bf1ed3489sm8719233pls.143.2022.07.13.05.25.32 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 13 Jul 2022 05:25:33 -0700 (PDT) From: Like Xu X-Google-Original-From: Like Xu To: Sean Christopherson , Paolo Bonzini Cc: Jim Mattson , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, Like Xu Subject: [PATCH 3/7] KVM: x86/pmu: Avoid setting BIT_ULL(-1) to pmu->host_cross_mapped_mask Date: Wed, 13 Jul 2022 20:25:02 +0800 Message-Id: <20220713122507.29236-4-likexu@tencent.com> X-Mailer: git-send-email 2.37.0 In-Reply-To: <20220713122507.29236-1-likexu@tencent.com> References: <20220713122507.29236-1-likexu@tencent.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Like Xu In the extreme case of host counters multiplexing and contention, the perf_event requested by the guest's pebs counter is not allocated to any actual physical counter, in which case hw.idx is bookkept as -1, resulting in an out-of-bounds access to host_cross_mapped_mask. Fixes: 854250329c02 ("KVM: x86/pmu: Disable guest PEBS temporarily in two rare situations") Signed-off-by: Like Xu --- arch/x86/kvm/vmx/pmu_intel.c | 11 +++++------ 1 file changed, 5 insertions(+), 6 deletions(-) diff --git a/arch/x86/kvm/vmx/pmu_intel.c b/arch/x86/kvm/vmx/pmu_intel.c index 53ccba896e77..1588627974fa 100644 --- a/arch/x86/kvm/vmx/pmu_intel.c +++ b/arch/x86/kvm/vmx/pmu_intel.c @@ -783,20 +783,19 @@ static void intel_pmu_cleanup(struct kvm_vcpu *vcpu) void intel_pmu_cross_mapped_check(struct kvm_pmu *pmu) { struct kvm_pmc *pmc = NULL; - int bit; + int bit, hw_idx; for_each_set_bit(bit, (unsigned long *)&pmu->global_ctrl, X86_PMC_IDX_MAX) { pmc = intel_pmc_idx_to_pmc(pmu, bit); if (!pmc || !pmc_speculative_in_use(pmc) || - !intel_pmc_is_enabled(pmc)) + !intel_pmc_is_enabled(pmc) || !pmc->perf_event) continue; - if (pmc->perf_event && pmc->idx != pmc->perf_event->hw.idx) { - pmu->host_cross_mapped_mask |= - BIT_ULL(pmc->perf_event->hw.idx); - } + hw_idx = pmc->perf_event->hw.idx; + if (hw_idx != pmc->idx && hw_idx != -1) + pmu->host_cross_mapped_mask |= BIT_ULL(hw_idx); } }