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Mon, 25 Mar 2024 08:51:05 +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 g//rAPk6AWb3JQAAD6G6ig (envelope-from ); Mon, 25 Mar 2024 08:51:05 +0000 Message-ID: Date: Mon, 25 Mar 2024 09:51:04 +0100 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 v2] mm/slub: mark racy accesses on slab->slabs Content-Language: en-US To: Chengming Zhou , linke li Cc: xujianhao01@gmail.com, Christoph Lameter , Pekka Enberg , David Rientjes , Joonsoo Kim , Andrew Morton , Roman Gushchin , Hyeonggon Yoo <42.hyeyoo@gmail.com>, linux-mm@kvack.org, linux-kernel@vger.kernel.org References: <8b146695-4ff5-4f9a-ab64-6cbed4168f98@suse.cz> From: Vlastimil Babka In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Spam-Score: -2.05 X-Rspamd-Server: rspamd1.dmz-prg2.suse.org X-Spam-Flag: NO X-Spamd-Result: default: False [-2.05 / 50.00]; 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RCVD_TLS_ALL(0.00)[]; SUSPICIOUS_RECIPS(1.50)[]; RBL_SPAMHAUS_BLOCKED_OPENRESOLVER(0.00)[2a07:de40:b281:104:10:150:64:97:from] X-Spam-Level: Authentication-Results: smtp-out2.suse.de; dkim=pass header.d=suse.cz header.s=susede2_rsa header.b=XfwZd6ES; dkim=pass header.d=suse.cz header.s=susede2_ed25519 header.b=AyQURhGX X-Rspamd-Queue-Id: 1EDF05C448 On 3/25/24 9:49 AM, Chengming Zhou wrote: > On 2024/3/25 16:48, Vlastimil Babka wrote: >> On 3/21/24 4:48 AM, linke li wrote: >>> The reads of slab->slabs are racy because it may be changed by >>> put_cpu_partial concurrently. In slabs_cpu_partial_show() and >>> show_slab_objects(), slab->slabs is only used for showing information. >>> >>> Data-racy reads from shared variables that are used only for diagnostic >>> purposes should typically use data_race(), since it is normally not a >>> problem if the values are off by a little. >>> >>> This patch is aimed at reducing the number of benign races reported by >>> KCSAN in order to focus future debugging effort on harmful races. >>> >>> Signed-off-by: linke li >>> Reviewed-by: Chengming Zhou >> >> Chengming provided feedback to v1 but not offered a Reviewed-by: AFAICS? Or >> maybe will offer it now? :) > > Ah, right. > > Reviewed-by: Chengming Zhou Thanks, added to slab/for-6.10/cleanup