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Wed, 28 Oct 2026 19:05:05 -0700 (PDT) Received: from osman.mioffice.cn ([43.224.245.178]) by smtp.gmail.com with ESMTPSA id 98e67ed59e1d1-3ae55d1650csm2351887a91.1.2026.10.28.19.05.01 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 28 Oct 2026 19:05:05 -0700 (PDT) From: Zhan Xusheng To: akpm@linux-foundation.org Cc: hannes@cmpxchg.org, mhocko@kernel.org, roman.gushchin@linux.dev, shakeel.butt@linux.dev, muchun.song@linux.dev, penguin-kernel@I-love.SAKURA.ne.jp, tj@kernel.org, mkoutny@suse.com, cui.tao@linux.dev, cgroups@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, zhanxusheng@xiaomi.com Subject: Re: [PATCH v2] mm: memcontrol: don't miss processes whose leader has exited in OOM scans Date: Thu, 29 Oct 2026 10:04:59 +0800 Message-ID: <20261029020459.3335597-1-zhanxusheng1024@gmail.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: References: X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit On Wed, Oct 28, 2026 at 02:40:35PM +0000, sashiko-bot@kernel.org wrote: > - [High] mm: memcontrol: missing CSS_TASK_ITER_WITH_DEAD in mem_cgroup_scan_tasks() css_task_iter_advance() drops PF_EXITING tasks with !signal->live before it looks at CSS_TASK_ITER_PROCS, so the current code doesn't see such a victim either. The patch keeps that. The changelog's "until it is gone" should read "while signal->live is non-zero"; I'll fix it if there is a v3. > - [Medium] mm: memcontrol: mem_cgroup_scan_skip() exposes left-behind exiting threads That needs every remaining thread to be past exit_signals() while signal->live is still non-zero; once it drops to zero the iterator hides the left-behind thread too. Without the patch, the left-behind leader exposes the moved process to the source memcg's scans until then. Thanks, Zhan Xusheng