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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> X-Mailing-List: linux-erofs@lists.ozlabs.org List-Id: List-Help: List-Owner: List-Post: List-Subscribe: , , List-Unsubscribe: Precedence: list MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20260223032641.1859381-1-ziy@nvidia.com> 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.