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=-9.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS 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 2A746C282E1 for ; Sat, 25 May 2019 00:54:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 03AF620863 for ; Sat, 25 May 2019 00:54:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726462AbfEYAyu (ORCPT ); Fri, 24 May 2019 20:54:50 -0400 Received: from ozlabs.org ([203.11.71.1]:42955 "EHLO ozlabs.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726273AbfEYAyt (ORCPT ); Fri, 24 May 2019 20:54:49 -0400 Received: by ozlabs.org (Postfix, from userid 1034) id 459lBb45HVz9sB8; Sat, 25 May 2019 10:54:47 +1000 (AEST) X-powerpc-patch-notification: thanks X-powerpc-patch-commit: 3202e35ec1c8fc19cea24253ff83edf702a60a02 X-Patchwork-Hint: ignore In-Reply-To: <20190511024217.4013-2-ravi.bangoria@linux.ibm.com> To: Ravi Bangoria , peterz@infradead.org, jolsa@redhat.com, maddy@linux.vnet.ibm.com From: Michael Ellerman Cc: Ravi Bangoria , linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org, acme@kernel.org Subject: Re: [PATCH 2/2] powerpc/perf: Fix mmcra corruption by bhrb_filter Message-Id: <459lBb45HVz9sB8@ozlabs.org> Date: Sat, 25 May 2019 10:54:47 +1000 (AEST) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, 2019-05-11 at 02:42:17 UTC, Ravi Bangoria wrote: > Consider a scenario where user creates two events: > > 1st event: > attr.sample_type |= PERF_SAMPLE_BRANCH_STACK; > attr.branch_sample_type = PERF_SAMPLE_BRANCH_ANY; > fd = perf_event_open(attr, 0, 1, -1, 0); > > This sets cpuhw->bhrb_filter to 0 and returns valid fd. > > 2nd event: > attr.sample_type |= PERF_SAMPLE_BRANCH_STACK; > attr.branch_sample_type = PERF_SAMPLE_BRANCH_CALL; > fd = perf_event_open(attr, 0, 1, -1, 0); > > It overrides cpuhw->bhrb_filter to -1 and returns with error. > > Now if power_pmu_enable() gets called by any path other than > power_pmu_add(), ppmu->config_bhrb(-1) will set mmcra to -1. > > Signed-off-by: Ravi Bangoria > Reviewed-by: Madhavan Srinivasan Applied to powerpc fixes, thanks. https://git.kernel.org/powerpc/c/3202e35ec1c8fc19cea24253ff83edf7 cheers