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=-19.7 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham 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 DF11CC43214 for ; Tue, 10 Aug 2021 14:15:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C7CBA60FDA for ; Tue, 10 Aug 2021 14:15:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S242554AbhHJOQQ (ORCPT ); Tue, 10 Aug 2021 10:16:16 -0400 Received: from mail.kernel.org ([198.145.29.99]:52758 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S242395AbhHJOPy (ORCPT ); Tue, 10 Aug 2021 10:15:54 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id C3A5A60F94; Tue, 10 Aug 2021 14:15:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1628604932; bh=jC6uSCrgt69kXfrpA/d+Zpv7RChIWevKRH+aKooCZ/c=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=fXx6eHWArKZe5Jr5YlScKwnc+I9Lv35SxtAGwKc0cHz+0DHGQrZD605dRlFlTvVzb Cy6Eo2WuZT5ubBxbcf8e8J9ZmkLTST7ZkFdosG0O03Hvpw634dBXtJa0vTdFDAMHeY iPSr4ebaz5sPmoiDIkFj64Rh87VfHPzGnpR29JXlKKb9GpjJmV0rP95JoGkodAWRvW KjBkhFNAHhIlkqAvsFQvh924qKLzTk+bQVfvVKVnB7cYin4PNJEen2DWgMA/DsE4iV LjLQu0QYYAK+c28iy8stODayiTDKaw2oPhzmQkk/ekWkMH6ds1LqKkpuJQx3bz+q2f MojgDOaTs+x1A== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Peter Zijlstra , Vince Weaver , Like Xu , Sasha Levin , linux-perf-users@vger.kernel.org Subject: [PATCH AUTOSEL 5.13 20/24] perf/x86: Fix out of bound MSR access Date: Tue, 10 Aug 2021 10:15:01 -0400 Message-Id: <20210810141505.3117318-20-sashal@kernel.org> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20210810141505.3117318-1-sashal@kernel.org> References: <20210810141505.3117318-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Peter Zijlstra [ Upstream commit f4b4b45652578357031fbbef7f7a1b04f6fa2dc3 ] On Wed, Jul 28, 2021 at 12:49:43PM -0400, Vince Weaver wrote: > [32694.087403] unchecked MSR access error: WRMSR to 0x318 (tried to write 0x0000000000000000) at rIP: 0xffffffff8106f854 (native_write_msr+0x4/0x20) > [32694.101374] Call Trace: > [32694.103974] perf_clear_dirty_counters+0x86/0x100 The problem being that it doesn't filter out all fake counters, in specific the above (erroneously) tries to use FIXED_BTS. Limit the fixed counters indexes to the hardware supplied number. Reported-by: Vince Weaver Signed-off-by: Peter Zijlstra (Intel) Tested-by: Vince Weaver Tested-by: Like Xu Link: https://lkml.kernel.org/r/YQJxka3dxgdIdebG@hirez.programming.kicks-ass.net Signed-off-by: Sasha Levin --- arch/x86/events/core.c | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-) diff --git a/arch/x86/events/core.c b/arch/x86/events/core.c index 1eb45139fcc6..3092fbf9dbe4 100644 --- a/arch/x86/events/core.c +++ b/arch/x86/events/core.c @@ -2489,13 +2489,15 @@ void perf_clear_dirty_counters(void) return; for_each_set_bit(i, cpuc->dirty, X86_PMC_IDX_MAX) { - /* Metrics and fake events don't have corresponding HW counters. */ - if (is_metric_idx(i) || (i == INTEL_PMC_IDX_FIXED_VLBR)) - continue; - else if (i >= INTEL_PMC_IDX_FIXED) + if (i >= INTEL_PMC_IDX_FIXED) { + /* Metrics and fake events don't have corresponding HW counters. */ + if ((i - INTEL_PMC_IDX_FIXED) >= hybrid(cpuc->pmu, num_counters_fixed)) + continue; + wrmsrl(MSR_ARCH_PERFMON_FIXED_CTR0 + (i - INTEL_PMC_IDX_FIXED), 0); - else + } else { wrmsrl(x86_pmu_event_addr(i), 0); + } } bitmap_zero(cpuc->dirty, X86_PMC_IDX_MAX); -- 2.30.2