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 Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 45095C38A02 for ; Fri, 28 Oct 2022 13:59:53 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id BF2CA6B0071; Fri, 28 Oct 2022 09:59:52 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id B87B36B0073; Fri, 28 Oct 2022 09:59:52 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id A6A876B0074; Fri, 28 Oct 2022 09:59:52 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0010.hostedemail.com [216.40.44.10]) by kanga.kvack.org (Postfix) with ESMTP id 97B8E6B0071 for ; Fri, 28 Oct 2022 09:59:52 -0400 (EDT) Received: from smtpin23.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay05.hostedemail.com (Postfix) with ESMTP id 4F7B541241 for ; Fri, 28 Oct 2022 13:59:52 +0000 (UTC) X-FDA: 80070516624.23.5581D69 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by imf13.hostedemail.com (Postfix) with ESMTP id EF7A02001C for ; Fri, 28 Oct 2022 13:59:50 +0000 (UTC) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id DC43C6288C; Fri, 28 Oct 2022 13:59:49 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 4C4ADC433D6; Fri, 28 Oct 2022 13:59:48 +0000 (UTC) Date: Fri, 28 Oct 2022 14:59:44 +0100 From: Catalin Marinas To: Waiman Long Cc: Andrew Morton , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Muchun Song Subject: Re: [PATCH] mm/kmemleak: Prevent soft lockup in kmemleak_scan()'s object iteration loops Message-ID: References: <20221020175619.366317-1-longman@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20221020175619.366317-1-longman@redhat.com> ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1666965591; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=KTVnEOniSlE7pMIiT0llRsAY6ZF5kejQBu7gdgG2oPs=; b=OQTnChfAepN2jZutzztlxlBVaqGs37VtzgDSR8l0WIGMgJ67Q6NDUOBIP6jg/ZJwwZ6zkM N+rJYn85W8GrQeRX8VFyW5294oEXZSbQN054DqI8SWrgpSm4piyhxVrfxMTXjOo5xjXcRR +gFhjhMe5msafq8MsKyqd8EygNBRzbA= ARC-Authentication-Results: i=1; imf13.hostedemail.com; dkim=none; spf=pass (imf13.hostedemail.com: domain of cmarinas@kernel.org designates 139.178.84.217 as permitted sender) smtp.mailfrom=cmarinas@kernel.org; dmarc=fail reason="SPF not aligned (relaxed), No valid DKIM" header.from=arm.com (policy=none) ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1666965591; a=rsa-sha256; cv=none; b=qS8XQ8zAwFSr0/+NsOkUcoeD3/4Gn/sLHtK+WcIUcSbi1NLB3v0yfk20BJqDOWbm2++49A YuWSNbd0rTRxCE4UO4Y+bCaBDTPl75b5R0XozIm2gSEJmLudd5I/b32VbdcuBxpdC4jytg SzItli2qbUdl4vsRKSdP5zPkwPK0oXQ= Authentication-Results: imf13.hostedemail.com; dkim=none; spf=pass (imf13.hostedemail.com: domain of cmarinas@kernel.org designates 139.178.84.217 as permitted sender) smtp.mailfrom=cmarinas@kernel.org; dmarc=fail reason="SPF not aligned (relaxed), No valid DKIM" header.from=arm.com (policy=none) X-Rspam-User: X-Rspamd-Queue-Id: EF7A02001C X-Rspamd-Server: rspam03 X-Stat-Signature: wboq8dhwnxjqwomx8ey5191wco7ceraf X-HE-Tag: 1666965590-829874 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Thu, Oct 20, 2022 at 01:56:19PM -0400, Waiman Long wrote: > Commit 6edda04ccc7c ("mm/kmemleak: prevent soft lockup in first object > iteration loop of kmemleak_scan()") adds cond_resched() in the first > object iteration loop of kmemleak_scan(). However, it turns that the > 2nd objection iteration loop can still cause soft lockup to happen in > some cases. So add a cond_resched() call in the 2nd and 3rd loops as > well to prevent that and for completeness. > > Signed-off-by: Waiman Long Acked-by: Catalin Marinas