From patchwork Mon Nov 23 12:22:06 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 330668 Delivered-To: patch@linaro.org Received: by 2002:a92:ae0b:0:0:0:0:0 with SMTP id s11csp2001141ilh; Mon, 23 Nov 2020 05:32:01 -0800 (PST) X-Google-Smtp-Source: ABdhPJwETaN4mzRjuocckWZ0aCt34iLl5jqgwBW7/AI/1f2BLMZMRZ9ZtbfpNqJ8Q30/gHEpmL37 X-Received: by 2002:a17:906:f8c5:: with SMTP id lh5mr46425341ejb.77.1606138190933; Mon, 23 Nov 2020 05:29:50 -0800 (PST) ARC-Seal: i=1; a=rsa-sha256; t=1606138190; cv=none; d=google.com; s=arc-20160816; b=No7wJ0b519X32vcgvgWEt/hEPF4Ep2bOcIhmHNtgImtKtv1HLpNWXOdgxGjxZvPS1n HPAs8/aqMfcgrJ78ZXt/UK1pUplclMGkrgk1/2d1Ui6/+SXpDUQNEKUS6cNwXM5kPSzA WYg5aSfFIwR7+PC47h6g4GtJapDlK2ABSSvHFYG2ezuHe3Ioqtw4mAItGAoaLfu5rHQd 6V+kBHAkU914xD5MQ7KlJeahrjj6b2aa4Ad3M3mKPzDb0CqwWcohLOo8LDr9NWAHcPKY 9o+xBQffY4CjHSz7Dpse2rN1OkyJrdn0aq0xmrSX9i9lUfsf59/hGkUw8/JIEGoabe2u aRCQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:content-transfer-encoding:mime-version :user-agent:references:in-reply-to:message-id:date:subject:cc:to :from:dkim-signature; bh=uqjTUFYmHyEu2Fr5tl+gHe628iCiZZcNkQ1Sxc2stfE=; b=r9ho8k4l6HPJ7W+nhFXvZzHhAlKu9k5F9WjUVsLZuE3z/KdbwyRekYoxcpyWnfwPXV EkrD+YV+b7Dct1eyeaR7kKqjksbd7id7nRhHqxLcOvKGXbxLbxqsPFmvjLUkJlW1vBd2 cvOWqyv1VEKabJtVe/a4AfGFgx5C5KPSI1XCHPooXRrG+TOkR7S6Vz84gEmwcYQnJoTd HA5lDvShDK5WWLv3dd+U2Igb2ca19kau9Bu5/9GESNxQSZGqRk1Ai1Jf8vvhOsNh8BKw rfs9cXoBuuEOW120aQATf6sBPxoORzeBVw8pGrtltym32fb8TGtQO3oHqcpg3Yma1MnQ uMMA== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@linuxfoundation.org header.s=korg header.b="TNgW3y4/"; spf=pass (google.com: domain of stable-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=stable-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=linuxfoundation.org Return-Path: Received: from vger.kernel.org (vger.kernel.org. [23.128.96.18]) by mx.google.com with ESMTP id i9si4048174edt.371.2020.11.23.05.29.50; Mon, 23 Nov 2020 05:29:50 -0800 (PST) Received-SPF: pass (google.com: domain of stable-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18; Authentication-Results: mx.google.com; dkim=pass header.i=@linuxfoundation.org header.s=korg header.b="TNgW3y4/"; spf=pass (google.com: domain of stable-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=stable-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=linuxfoundation.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730855AbgKWMb2 (ORCPT + 14 others); Mon, 23 Nov 2020 07:31:28 -0500 Received: from mail.kernel.org ([198.145.29.99]:42222 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730847AbgKWMbZ (ORCPT ); Mon, 23 Nov 2020 07:31:25 -0500 Received: from localhost (83-86-74-64.cable.dynamic.v4.ziggo.nl [83.86.74.64]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 72BB92076E; Mon, 23 Nov 2020 12:31:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1606134685; bh=m+6Ivt4YjbhoMgnnjH0z+omp/8njCcODphmrNNh/EGQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=TNgW3y4/OS+DAzAiYdVkl/T+u2NC72rCOEWM07xaiLbNWpalg3jgAkAN3/h6SoTch kKSxToopOKRDJiqAM2tcofHo9lWWzQ+kwUONMIT6/IlJWkATH1Bdlsx8F10ivLhi8l rwl42dPkrae9CP+4nNElmoAs8VSAA1QcD78O4Fk4= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Leo Yan , Jiri Olsa , Arnaldo Carvalho de Melo , Sasha Levin Subject: [PATCH 4.19 46/91] perf lock: Dont free "lock_seq_stat" if read_count isnt zero Date: Mon, 23 Nov 2020 13:22:06 +0100 Message-Id: <20201123121811.555738702@linuxfoundation.org> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20201123121809.285416732@linuxfoundation.org> References: <20201123121809.285416732@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Leo Yan [ Upstream commit b0e5a05cc9e37763c7f19366d94b1a6160c755bc ] When execute command "perf lock report", it hits failure and outputs log as follows: perf: builtin-lock.c:623: report_lock_release_event: Assertion `!(seq->read_count < 0)' failed. Aborted This is an imbalance issue. The locking sequence structure "lock_seq_stat" contains the reader counter and it is used to check if the locking sequence is balance or not between acquiring and releasing. If the tool wrongly frees "lock_seq_stat" when "read_count" isn't zero, the "read_count" will be reset to zero when allocate a new structure at the next time; thus it causes the wrong counting for reader and finally results in imbalance issue. To fix this issue, if detects "read_count" is not zero (means still have read user in the locking sequence), goto the "end" tag to skip freeing structure "lock_seq_stat". Fixes: e4cef1f65061 ("perf lock: Fix state machine to recognize lock sequence") Signed-off-by: Leo Yan Acked-by: Jiri Olsa Link: https://lore.kernel.org/r/20201104094229.17509-2-leo.yan@linaro.org Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: Sasha Levin --- tools/perf/builtin-lock.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) -- 2.27.0 diff --git a/tools/perf/builtin-lock.c b/tools/perf/builtin-lock.c index 6e0189df2b3ba..0cb7f7b731fb0 100644 --- a/tools/perf/builtin-lock.c +++ b/tools/perf/builtin-lock.c @@ -620,7 +620,7 @@ static int report_lock_release_event(struct perf_evsel *evsel, case SEQ_STATE_READ_ACQUIRED: seq->read_count--; BUG_ON(seq->read_count < 0); - if (!seq->read_count) { + if (seq->read_count) { ls->nr_release++; goto end; }