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 gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 53962EF5862 for ; Mon, 23 Feb 2026 04:29:21 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id B863910E20F; Mon, 23 Feb 2026 04:29:20 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=fail reason="signature verification failed" (2048-bit key; secure) header.d=infradead.org header.i=@infradead.org header.b="EGbJhp6R"; dkim-atps=neutral Received: from casper.infradead.org (casper.infradead.org [90.155.50.34]) by gabe.freedesktop.org (Postfix) with ESMTPS id E3B9410E20F for ; Mon, 23 Feb 2026 04:29:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=ZHLh3cKXZKjxYpTI2A5f4Usbzkmd+cL0G7dSp1H+f/4=; b=EGbJhp6RfZrjSCE2rvuy7WsEoF Vned+yo1lQzDtP/c65f5E63hpbQmW6y7ucwgA36tqcLB4ihf5O1KbaWOvkp2IapQ30+AHXOFJWjXB /RWGxNJjNkWwtJ2vl+0DzbR9bVX7lJX6j6a8nOhuWxbaagFLoHIZzmBvLxcDmeGhZ79DT3yuiIuoU RNWPH+fe4mULAm0Y7nJRODD7d45hZJKcUrkZcuC7gBNSAFo6dq/qtqDzakWfbPlqe2ane9otf5tBQ Ldl35tPIftkoei5Z3t519AT4iV+zg/Awk4rFsN6hLBbWwOB9jXkwPiv7EEbVbPCilvKeUUBH9RNd1 qxBZyxog==; Received: from willy by casper.infradead.org with local (Exim 4.98.2 #2 (Red Hat Linux)) id 1vuNYo-0000000Drlf-3eoa; Mon, 23 Feb 2026 04:28:42 +0000 Date: Mon, 23 Feb 2026 04:28:42 +0000 From: Matthew Wilcox To: Zi Yan Cc: linux-mm@kvack.org, David Hildenbrand , Andrew Morton , linux-erofs@lists.ozlabs.org, linux-block@vger.kernel.org, dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, Lorenzo Stoakes , Baolin Wang , "Liam R. Howlett" , Nico Pache , Ryan Roberts , Dev Jain , Barry Song , Lance Yang , Suren Baghdasaryan , Michal Hocko , Brendan Jackman , Johannes Weiner , Jason Xing , Yushan Zhou , "Masami Hiramatsu (Google)" , Vlastimil Babka , Christoph Lameter , David Rientjes , Roman Gushchin , Harry Yoo , Christian Koenig , Huang Rui , Matthew Auld , Matthew Brost , Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , David Airlie , Simona Vetter , Jens Axboe , Christian Brauner , K Prateek Nayak , Davidlohr Bueso , Eric Sandeen , Greg Kroah-Hartman , Arve =?iso-8859-1?B?SGr4bm5lduVn?= , Todd Kjos , Carlos Llamas , Alice Ryhl , Damien Le Moal , Johannes Thumshirn , Dennis Zhou , Tejun Heo , Gao Xiang , Yue Hu , Jeffle Xu , Sandeep Dhavale , Hongbo Li , Chunhai Guo Subject: Re: [PATCH v1 00/11] Zero page->private when freeing pages Message-ID: References: <20260223032641.1859381-1-ziy@nvidia.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20260223032641.1859381-1-ziy@nvidia.com> X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" On Sun, Feb 22, 2026 at 10:26:30PM -0500, Zi Yan wrote: > Based on a recent discussion with David Hildenbrand on page->private > is not zero when a page is freed[1], this patchset is trying to fix all > users do not zero ->private when freeing a page and add checks to make > sure all freed pages have ->private set to zero. For compound pages, > both head page and tail pages need to have ->private set to zero. Sorry, I didn't notice this conversation. It seems entirely unnecessary to me to zero out page->private before freeing. I'm a bit confused that ac1ea219590c was needed too; I thought we cleared page->private in the allocation path, and I don't see why it needs to be cleared in the freeing path. split_page() should be clearing page->private. Can we discuss this at the THP Cabal meeting on Wednesday? I don't think that introducing this new rule that page->private must be cleared by the users is a good idea.