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Tue, 13 Jan 2026 14:13:42 +0000 (UTC) Received: from dovecot-director2.suse.de ([2a07:de40:b281:106:10:150:64:167]) by imap1.dmz-prg2.suse.org with ESMTPSA id wn37CRZTZmkqPwAAD6G6ig (envelope-from ); Tue, 13 Jan 2026 14:13:42 +0000 Message-ID: <11e83aa3-0ebb-44ad-b814-a76fd244cbf1@suse.cz> Date: Tue, 13 Jan 2026 15:13:41 +0100 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH V6 0/9] mm/slab: reduce slab accounting memory overhead by allocating slabobj_ext metadata within unsed slab space To: Harry Yoo , akpm@linux-foundation.org Cc: andreyknvl@gmail.com, cl@gentwo.org, dvyukov@google.com, glider@google.com, hannes@cmpxchg.org, linux-mm@kvack.org, mhocko@kernel.org, muchun.song@linux.dev, rientjes@google.com, roman.gushchin@linux.dev, ryabinin.a.a@gmail.com, shakeel.butt@linux.dev, surenb@google.com, vincenzo.frascino@arm.com, yeoreum.yun@arm.com, tytso@mit.edu, adilger.kernel@dilger.ca, linux-ext4@vger.kernel.org, linux-kernel@vger.kernel.org, cgroups@vger.kernel.org, hao.li@linux.dev References: <20260113061845.159790-1-harry.yoo@oracle.com> From: Vlastimil Babka Content-Language: en-US In-Reply-To: <20260113061845.159790-1-harry.yoo@oracle.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Rspamd-Server: rspam11 X-Rspamd-Queue-Id: AEAF014000B X-Rspam-User: X-Stat-Signature: 5nwqu1g69omefnh7y733tdo7wkzmaohk X-HE-Tag: 1768313623-95787 X-HE-Meta: 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 4DxAK8c8 lqhftX3tY1MZ/HR0pbXsuOGrbH1pXynQTCzAwdsgVeR/SgzGxRNX2rGogOP2Zuq2KwnDJiokPCvrGhRPIJcEkmUjx5PPRsVyr+Q3W+QCtho0BUhtWTtq5/q3gyN9o8eDGXQxS4SQgzxsYEHsyvZaQU33DpSEovuVmIq4xZqVAeGr2Oi76JFRfLAkoOkwoZM7w2BzKIRR9usv3WRrk/lPpgXxOMyWXPn++rB6cIP8MrPOseWT2tObKfD6tMh2nBIgUvKEl/maZNNLCiookga5DZ5xeuJcg2ybdE/qP6sH9uej3P3PNBwfwqX6MFfRGuEfBoOWvQYAzk+JeTc6DBPdXFBN74ottnYfZKh1dfyIRxevjj10tP9nV1Y492fxVSqjHSIUSnnW8GIlJUOwd4vsboizZhz7gemN6ZKhIfjZ5LrhreP3bxE2aT+mCAmH19jGv6vWklGoudfhNc8Q= 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: List-Subscribe: List-Unsubscribe: On 1/13/26 7:18 AM, Harry Yoo wrote: > V5: https://lore.kernel.org/linux-mm/20260105080230.13171-1-harry.yoo@oracle.com > V5 -> V6: > > - Patch 1: Added Closes: tag for related discussion (Vlastimil) > https://lore.kernel.org/linux-mm/1372138e-5837-4634-81de-447a1ef0a5ad@suse.cz > > - Patch 3: Addressed Vlastimil's comments > https://lore.kernel.org/linux-mm/e28c08e4-5048-429b-97a0-8d51e494efcd@suse.cz > > - Patch 4: Fixed incorrect function prototype of slab_obj_ext() on > !CONFIG_SLAB_OBJ_EXT builds and kept pointer type in > free_slab_obj_exts() (Hao, Vlastimil) > https://lore.kernel.org/linux-mm/n6kyluk3nahdxytwek4ijzy4en6mc6ps7fjjgftww4ith7llom@cijm4who24w2 > https://lore.kernel.org/linux-mm/473d479c-4eae-4589-b8c2-e2a29e8e6bc1@suse.cz > > - Patch 7, 9: Rewrote obj_exts_in_slab() to check if the pointer is within the > slab's range, and distinguish by stride (Vlastimil) > https://lore.kernel.org/linux-mm/644e163d-edd9-4128-9516-0f70a25526df@suse.cz > > - Patch 9: Fixed potentioal memory leak due to incorrect impl. of > obj_exts_in_object() (Vlastimil) > https://lore.kernel.org/linux-mm/8c67dcbe-f393-4da6-8d24-f9da79c246c4@suse.cz/ > > - Patch 9: Fixed incorrect ksize() implementation (Hao) > https://lore.kernel.org/linux-mm/fgx3lapibabra4x7tewx55nuvxz235ruvm3agpprjbdcmt3rc6@h54ln5tfdssz Merged to slab/for-7.0/obj_metadata and slab/for-next, thanks!