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Howlett" , Nico Pache , Ryan Roberts , Dev Jain , Barry Song , Lance Yang , Usama Arif , Kiryl Shutsemau , Vlastimil Babka , Suren Baghdasaryan , Brendan Jackman , "linux-mm@kvack.org" , "cgroups@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "stable@vger.kernel.org" , Daejun Park X-Priority: 3 X-Content-Kind-Code: NORMAL In-Reply-To: X-CPGS-Detection: blocking_info_exchange X-Drm-Type: N,general X-Msg-Generator: Mail X-Msg-Type: PERSONAL X-Reply-Demand: N Message-ID: <20261105010612epcms2p60abe5ce24c4ca7d61236b613a517fe2a@epcms2p6> Date: Thu, 05 Nov 2026 10:06:12 +0900 X-CMS-MailID: 20261105010612epcms2p60abe5ce24c4ca7d61236b613a517fe2a Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="utf-8" X-Sendblock-Type: AUTO_CONFIDENTIAL CMS-TYPE: 102P X-CPGSPASS: Y X-CPGSPASS: Y cpgsPolicy: CPGSC10-223,Y X-CFilter-Loop: Reflected X-CMS-RootMailID: 20261104163327epcas2p1f056cd220dc0d3e40e6fcea082f01b74 References: <20261104-kpagecgroup-split-v1-0-f70e947fec85@samsung.com> <20261104-kpagecgroup-split-v1-1-f70e947fec85@samsung.com> On Wed Nov 4, 2026 at 11:33 AM EST, Zi Yan wrote: > Assign memcg data before clear_compound_head(), so lockless, > reference-free readers get the right value instead of bogus data from > the overlaid ->_nr_pages in the first tail page. Thanks, agreed. Your wording says why the assignment has to come before clear_compound_head(), which my comment left implicit. Thanks, Daejun