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=-2.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=no 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 3F3CBC38A24 for ; Thu, 7 May 2020 17:16:14 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 1261C208DB for ; Thu, 7 May 2020 17:16:13 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 1261C208DB Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id A1300900004; Thu, 7 May 2020 13:16:13 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 99BAA900002; Thu, 7 May 2020 13:16:13 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 863BA900004; Thu, 7 May 2020 13:16:13 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0250.hostedemail.com [216.40.44.250]) by kanga.kvack.org (Postfix) with ESMTP id 70070900002 for ; Thu, 7 May 2020 13:16:13 -0400 (EDT) Received: from smtpin30.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with ESMTP id 362E311913 for ; Thu, 7 May 2020 17:16:13 +0000 (UTC) X-FDA: 76790576226.30.jam16_70776fdc8b708 X-HE-Tag: jam16_70776fdc8b708 X-Filterd-Recvd-Size: 1756 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by imf26.hostedemail.com (Postfix) with ESMTP for ; Thu, 7 May 2020 17:16:12 +0000 (UTC) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 5E5FC30E; Thu, 7 May 2020 10:16:11 -0700 (PDT) Received: from gaia (unknown [172.31.20.19]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 80E833F305; Thu, 7 May 2020 10:16:10 -0700 (PDT) Date: Thu, 7 May 2020 18:16:08 +0100 From: Catalin Marinas To: Qian Cai Cc: Linux-MM , LKML , "Paul E. McKenney" Subject: Re: Kmemleak infrastructure improvement for task_struct leaks and call_rcu() Message-ID: <20200507171607.GD3180@gaia> References: <45D2D811-C3B0-442B-9744-415B4AC5CCDB@lca.pw> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <45D2D811-C3B0-442B-9744-415B4AC5CCDB@lca.pw> User-Agent: Mutt/1.10.1 (2018-07-13) X-Bogosity: Ham, tests=bogofilter, spamicity=0.000014, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Wed, May 06, 2020 at 12:22:37PM -0400, Qian Cai wrote: > What do you think about adding some aux call traces for kmemleak in > general? For example, if the tracking object is a task struct, it > would save call traces for the first and last call of both > get_task_struct() and put_task_struct(). Then, it could be expanded to > track other refcount-based leaks in the future. I don't mind adding additional tracking info if it helps with debugging. But if it's for improving false positives, I'd prefer to look deeper into figure out why the pointer reference graph tracking failed. Thanks. -- Catalin