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([2a02:6b6f:e750:1800:450:cba3:aec3:a1fd]) by smtp.gmail.com with ESMTPSA id 5b1f17b1804b1-479311ece7asm145085065e9.12.2025.12.06.09.27.29 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Sat, 06 Dec 2025 09:27:30 -0800 (PST) Message-ID: <17002374-e135-46a5-9e4c-c317ac9823ae@gmail.com> Date: Sat, 6 Dec 2025 17:27:29 +0000 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH 07/11] mm: Drop fake head checks and fix a race condition Content-Language: en-GB To: Kiryl Shutsemau , Andrew Morton , Muchun Song Cc: David Hildenbrand , Oscar Salvador , Mike Rapoport , Vlastimil Babka , Lorenzo Stoakes , Matthew Wilcox , Zi Yan , Baoquan He , Michal Hocko , Johannes Weiner , Jonathan Corbet , kernel-team@meta.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org References: <20251205194351.1646318-1-kas@kernel.org> <20251205194351.1646318-8-kas@kernel.org> From: Usama Arif In-Reply-To: <20251205194351.1646318-8-kas@kernel.org> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 05/12/2025 19:43, Kiryl Shutsemau wrote: > Fake heads are no longer in use, so checks for them should be removed. > > It simplifies compound_head() and page_ref_add_unless() substantially. > Would be good to mention in the commit message what the race condition is as its there in the subject. Probably can copy some text from the cover letter.