Received: by 2002:ab2:3350:0:b0:1f4:6588:b3a7 with SMTP id o16csp1711152lqe; Mon, 8 Apr 2024 19:03:11 -0700 (PDT) X-Forwarded-Encrypted: i=3; AJvYcCUlpMBmTOtzZyF0+sRq99CEZHepGKVYw5v+MU6s43cs0sb00ZqhhXAVAtyEjTdlrY/N8gIrf0Pg6P/6dzN94fmLOeOO3w91+MA7z1L1cw== X-Google-Smtp-Source: AGHT+IEERS8WAuYm7qvCL/k+kSZ+aJht8h60Ta/Xgs1tqtD+pk16shvw3wfyJ7Qn2GoKInWhysBg X-Received: by 2002:a50:ab51:0:b0:56e:2aef:f92e with SMTP id t17-20020a50ab51000000b0056e2aeff92emr5760216edc.17.1712628191281; Mon, 08 Apr 2024 19:03:11 -0700 (PDT) ARC-Seal: i=2; a=rsa-sha256; t=1712628191; cv=pass; d=google.com; s=arc-20160816; b=twrO6hRkMqL7w1z3OY1vioXAfxVq7shfVOk1J2iWxH4aGeKwR7pPQBFUgAH7WWZWFO XH19Gwc8Hs3oiig6RXRhASSPDMGm8oG2QibUMUJB2wVbfHZWK+my2W6OFpOpZXqSfz51 y5ODXAbwSMQufvCUbycE94rAriUqqjw3nkPFG6tp1SlDY62VPrGHU8JOpyOGFtUyiPhg dfRu094SaC9fSJ5NYu9oGeu/6SgiUPuc1I42UDXWW4v4HXysVQpXpaDfdNw9Aw77nbHa VBLUF/DNriSgPHq+7C9GrznyIIJDaAUszXw8NZrgdHPYxdZUBoyg9PoJKO6aVu8Xk7/j t51A== ARC-Message-Signature: i=2; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=cc:to:from:subject:message-id:references:mime-version :list-unsubscribe:list-subscribe:list-id:precedence:in-reply-to:date :dkim-signature; bh=2fpNLMOdTuzWqLni5ebK55upYwMGmEgOY//8538KyEg=; fh=nnPkcpdIv/zaUjXrzrjzuUelz5G362T92VNtrVqSLyw=; b=f8v7iTxWP/vk+c3hV/gCo8LjXzKMVEFozUcyQqYlnkcyyAsFzaC5b/B/PGwI72QzfE VwIdP2/ojt9I4KpemUBCGOEfFhzhy5h91ioac2ijpZD6pZPYFxxJ6CqWwtyIvqWHbubv 0vjkDeZTKPrSStCVXcWKEPFvF2yiUgzhZjQhjr2/JBGizM+B3BYlqxuVI+6Ce5sW/wCg gQQ4kC/yOfH3oEohEUXUYADiDlaBbwRd5AzcD7Dy89nSZGUZiaLkMYiow6Qp6LsdmbmK BmW/hP3mlKHF6eWvgPYlyo+RUoiFnOwStzIYk8VhkFEgt9blKpmK763yCZyTUnDuPSWv Ia6w==; dara=google.com ARC-Authentication-Results: i=2; mx.google.com; dkim=pass header.i=@google.com header.s=20230601 header.b=N8DNuWvL; arc=pass (i=1 spf=pass spfdomain=flex--seanjc.bounces.google.com dkim=pass dkdomain=google.com dmarc=pass fromdomain=google.com); spf=pass (google.com: domain of linux-kernel+bounces-136118-linux.lists.archive=gmail.com@vger.kernel.org designates 147.75.80.249 as permitted sender) smtp.mailfrom="linux-kernel+bounces-136118-linux.lists.archive=gmail.com@vger.kernel.org"; dmarc=pass (p=REJECT sp=REJECT dis=NONE) header.from=google.com Return-Path: Received: from am.mirrors.kernel.org (am.mirrors.kernel.org. [147.75.80.249]) by mx.google.com with ESMTPS id m2-20020a50d7c2000000b0056893d784f7si4085413edj.52.2024.04.08.19.03.11 for (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 08 Apr 2024 19:03:11 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel+bounces-136118-linux.lists.archive=gmail.com@vger.kernel.org designates 147.75.80.249 as permitted sender) client-ip=147.75.80.249; Authentication-Results: mx.google.com; dkim=pass header.i=@google.com header.s=20230601 header.b=N8DNuWvL; arc=pass (i=1 spf=pass spfdomain=flex--seanjc.bounces.google.com dkim=pass dkdomain=google.com dmarc=pass fromdomain=google.com); spf=pass (google.com: domain of linux-kernel+bounces-136118-linux.lists.archive=gmail.com@vger.kernel.org designates 147.75.80.249 as permitted sender) smtp.mailfrom="linux-kernel+bounces-136118-linux.lists.archive=gmail.com@vger.kernel.org"; dmarc=pass (p=REJECT sp=REJECT dis=NONE) header.from=google.com Received: from smtp.subspace.kernel.org (wormhole.subspace.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by am.mirrors.kernel.org (Postfix) with ESMTPS id 6B89C1F24375 for ; Tue, 9 Apr 2024 02:03:09 +0000 (UTC) Received: from localhost.localdomain (localhost.localdomain [127.0.0.1]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 4AD2B4F1E2; Tue, 9 Apr 2024 02:03:01 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="N8DNuWvL" Received: from mail-yb1-f202.google.com (mail-yb1-f202.google.com [209.85.219.202]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id DCBC556454 for ; Tue, 9 Apr 2024 02:02:58 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.219.202 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1712628180; cv=none; b=FnGcVURimgcRDxYF37rPjWYtNU94x8pavtaPSxlxkSuYVQ431wamCoWUfnSYBenzrqRGdimYc6aXxh9r8Srozn0+kcn99XPt8iL87isCjAIyZWjRJrJ3UPHE6u6N2p4/KLPZzWW6MyAzvI64vFFW87hhh67X5fGliAJzM5fqjxM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1712628180; c=relaxed/simple; bh=/66ANqhlgh6dfJsAL2UyKasucCcRFsXjIhwslGGnq/g=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=rk7Ze66J/gHZUUv+0OzYR6LHLlnCPv1aB+gaI1pvjvVs/vhVetcroq3/dBbl906yneSldwxcDpUDffC353Gt9E2RphsGbZxp7eZJ+2O7CQqRFOVNgf1Wm1hRSWrir2o+BQLGr5bkBHFpFqbn3e+QGSbru/d2KIohzPYNLyztnJI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--seanjc.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=N8DNuWvL; arc=none smtp.client-ip=209.85.219.202 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--seanjc.bounces.google.com Received: by mail-yb1-f202.google.com with SMTP id 3f1490d57ef6-dbf216080f5so8237395276.1 for ; Mon, 08 Apr 2024 19:02:58 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1712628178; x=1713232978; darn=vger.kernel.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=2fpNLMOdTuzWqLni5ebK55upYwMGmEgOY//8538KyEg=; b=N8DNuWvLg3Dek3uI8v83apdHF9SLE1XFPySDK9L1YGz45j9sYI4m337gzEk4m9My9l NBZLqmjGtvxWinETu8607auqI99rW7LmGKX3LDLxGfU4gwClUCXTmK2e0D0aj/0PPzsE wHD9atofGr8b3GKrEwObEHYTKBDnQasXEEdbFHHujjX4VDwzdz626Zq8vJVZIy54ghij wQXg/bPppavQqNokBrSLfRPz9OvL8PWlfB/Q/R/wdshr4V4XmCjmykbzO8EVVe9b1X+D 7a/Kd6QY+0ubKVMLkODNfwqv4sj6AOgxosVgBQLGJRrEMoewt2z7Zb1cQ1BQ0PIS9HeD P90g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1712628178; x=1713232978; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=2fpNLMOdTuzWqLni5ebK55upYwMGmEgOY//8538KyEg=; b=KMUxMzuQ2iDYy1QDJq/NUYr6K2pD723japKh0BBIJah+3AftEwmjte149QYE15BkYb pNMOnq0g59rrOemx9sNx/ZP+6c/CHuWrO04LWW7Gw53z4jyU1WBg8ofE/WzeX+j/XSHA wjDxMNZ0vna+1rDRJBdUKen/nvtT8tDsp0X0AeUoI3ctfePXNgsMrOsAqfTRD3ea0L/x 9+5My/2v+6+flgkbgvqtIL4Dw41Tzh//4XN/H6N97Ltz/Bx6e4ku6Xj11CjQK3FQ3uPN 99V9zqBQV3fxamEUTIt6ov6B1Y/nC6e6RzCSSGZKwuhe6b/MNPyb2StyTD653oGzNFjt /f+w== X-Forwarded-Encrypted: i=1; AJvYcCWZQ4272sJKcl3h9NukqRnyGAQLK3XSjC/ibEGoG1ityXuT/aILyWi3JtL105HxbD7NlqMPk4ePo9uynWv3575VWuyfIGuGt76BgLos X-Gm-Message-State: AOJu0YzZPlwyDwc5JLJYSqRyNqZ94QYV8Yyy8lNygqaviXqBWcg1aPL4 UJQpi/cDsbVEQZdkIoHU1zt0V84zy9yGHzqlrXzQQns5K55eE6M3+RZa4XuKd6yQUY72kpOV3Qs lPw== X-Received: from zagreus.c.googlers.com ([fda3:e722:ac3:cc00:7f:e700:c0a8:5c37]) (user=seanjc job=sendgmr) by 2002:a05:6902:c03:b0:dc2:1f34:fac4 with SMTP id fs3-20020a0569020c0300b00dc21f34fac4mr3156555ybb.2.1712628178083; Mon, 08 Apr 2024 19:02:58 -0700 (PDT) Date: Mon, 8 Apr 2024 19:01:33 -0700 In-Reply-To: <20240307011344.835640-1-seanjc@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20240307011344.835640-1-seanjc@google.com> X-Mailer: git-send-email 2.44.0.478.gd926399ef9-goog Message-ID: <171262750089.1420807.14858434543826601467.b4-ty@google.com> Subject: Re: [PATCH 0/3] KVM: VMX: Disable LBRs if CPU doesn't have callstacks From: Sean Christopherson To: Sean Christopherson , Peter Zijlstra , Ingo Molnar , Arnaldo Carvalho de Melo , Namhyung Kim , Paolo Bonzini Cc: linux-perf-users@vger.kernel.org, linux-kernel@vger.kernel.org, kvm@vger.kernel.org, Mingwei Zhang , Jim Mattson Content-Type: text/plain; charset="utf-8" On Wed, 06 Mar 2024 17:13:41 -0800, Sean Christopherson wrote: > Disable LBR virtualization if the CPU (or I guess perf) doesn't support > LBR callstacks, as KVM unconditionally creates the associated perf LBR > event with PERF_SAMPLE_BRANCH_CALL_STACK. That results in perf rejecting > the event, and cause LBR virtualization to silently fail. > > This was detected by running vmx_pmu_caps_test on older hardware. I didn't > tag it for stable because I can't imagine anyone is trying to use KVM's LBR > virtualization on pre-HSW. > > [...] Applied to kvm-x86 fixes, as I can't imagine anyone objecting to patch 2. [1/3] KVM: VMX: Snapshot LBR capabilities during module initialization https://github.com/kvm-x86/linux/commit/2a94a2761236 [2/3] perf/x86/intel: Expose existence of callback support to KVM https://github.com/kvm-x86/linux/commit/0c0241c12332 [3/3] KVM: VMX: Disable LBR virtualization if the CPU doesn't support LBR callstacks https://github.com/kvm-x86/linux/commit/0eb2416c8111 -- https://github.com/kvm-x86/linux/tree/next