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=-0.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED 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 92D40C3A5A1 for ; Thu, 22 Aug 2019 23:03:47 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 2765E233A0 for ; Thu, 22 Aug 2019 23:03:47 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="BBxVo2nN" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 2765E233A0 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linux-foundation.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id BA1216B035D; Thu, 22 Aug 2019 19:03:46 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id B513A6B035F; Thu, 22 Aug 2019 19:03:46 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id A66436B0360; Thu, 22 Aug 2019 19:03:46 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0015.hostedemail.com [216.40.44.15]) by kanga.kvack.org (Postfix) with ESMTP id 800436B035D for ; Thu, 22 Aug 2019 19:03:46 -0400 (EDT) Received: from smtpin09.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay04.hostedemail.com (Postfix) with SMTP id 277E6689C for ; Thu, 22 Aug 2019 23:03:46 +0000 (UTC) X-FDA: 75851592852.09.nerve57_3c21e0d48c29 X-HE-Tag: nerve57_3c21e0d48c29 X-Filterd-Recvd-Size: 2603 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf27.hostedemail.com (Postfix) with ESMTP for ; Thu, 22 Aug 2019 23:03:45 +0000 (UTC) Received: from akpm3.svl.corp.google.com (unknown [104.133.8.65]) (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 9C32B21848; Thu, 22 Aug 2019 23:03:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1566515024; bh=fgi/rgPJr0UBQTUlu1/65uSy+9MMhXIOvXFp0ALGfb0=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=BBxVo2nNziNaw3nAAEFAen1S7XiIO8Vta0pNHjnEDrJV2guXM6hZIbA3EBQnD27XU xx5lUT8HJgT0tzNJTsVuX+MYZ+kxVgP8Ozyil9XXkdjvISelPuFKSvf1uwNrSSSuuI gXZFDs+IVIjusG2rBR8LeQ8NVAbEX+BcR3Xuw3ow= Date: Thu, 22 Aug 2019 16:03:44 -0700 From: Andrew Morton To: Vlastimil Babka Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, "Kirill A. Shutemov" , Michal Hocko , Mel Gorman , Matthew Wilcox Subject: Re: [PATCH v2 0/4] debug_pagealloc improvements through page_owner Message-Id: <20190822160344.716eda34585271fa4a519d4c@linux-foundation.org> In-Reply-To: <20190820131828.22684-1-vbabka@suse.cz> References: <20190820131828.22684-1-vbabka@suse.cz> X-Mailer: Sylpheed 3.7.0 (GTK+ 2.24.32; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit 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 Tue, 20 Aug 2019 15:18:24 +0200 Vlastimil Babka wrote: > v2: also fix THP split handling (added Patch 1) per Kirill > > The debug_pagealloc functionality serves a similar purpose on the page > allocator level that slub_debug does on the kmalloc level, which is to detect > bad users. One notable feature that slub_debug has is storing stack traces of > who last allocated and freed the object. On page level we track allocations via > page_owner, but that info is discarded when freeing, and we don't track freeing > at all. This series improves those aspects. With both debug_pagealloc and > page_owner enabled, we can then get bug reports such as the example in Patch 4. > > SLUB debug tracking additionaly stores cpu, pid and timestamp. This could be > added later, if deemed useful enough to justify the additional page_ext > structure size. Thanks. I split [1/1] out of the series as a bugfix and turned this into a three-patch series.