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[109.81.31.149]) by smtp.gmail.com with ESMTPSA id ffacd0b85a97d-43b919e7372sm7234784f8f.34.2026.03.26.00.14.37 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 26 Mar 2026 00:14:37 -0700 (PDT) Date: Thu, 26 Mar 2026 08:14:36 +0100 From: Michal Hocko To: Qi Zheng Cc: hannes@cmpxchg.org, hughd@google.com, roman.gushchin@linux.dev, shakeel.butt@linux.dev, muchun.song@linux.dev, david@kernel.org, ljs@kernel.org, ziy@nvidia.com, harry.yoo@oracle.com, yosry.ahmed@linux.dev, imran.f.khan@oracle.com, kamalesh.babulal@oracle.com, axelrasmussen@google.com, yuanchu@google.com, weixugc@google.com, chenridong@huaweicloud.com, mkoutny@suse.com, akpm@linux-foundation.org, hamzamahfooz@linux.microsoft.com, apais@linux.microsoft.com, lance.yang@linux.dev, bhe@redhat.com, usamaarif642@gmail.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org, Qi Zheng Subject: Re: [PATCH v2 0/4] fix unexpected type conversions and potential overflows Message-ID: References: Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: On Wed 25-03-26 22:13:21, Qi Zheng wrote: > From: Qi Zheng > > Hi all, > > As Harry Yoo pointed out [1], in scenarios where massive state updates occur > (e.g., during the reparenting of LRU folios), the values passed to memcg stat > update functions can accumulate and exceed the upper limit of a 32-bit integer. Is this a real problem without reparenting? In other words is this a follow up for that work or something that we need on its own? -- Michal Hocko SUSE Labs