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AJvYcCXH7II7EWHr9AddxReM1CkxcRua4TMFNTE2RIBy/71i/tDe9ahz793B43XPYPSmxONXrCearPmJ2Q==@kvack.org X-Gm-Message-State: AOJu0YwNAMC76MmCvc3caqZKGamFM52pKW4qHrAOh7xPw/LAJ/yfE4ay sa05BnCLucD28pc7wpytNzIt3X37VGflhI72/+sbt7JPLJMA/nW/MJaItLxMhmn8j7ogAVX85pV zmcn9GeLg4Up6nTdDIw== X-Received: from wmqf8.prod.google.com ([2002:a05:600c:4e88:b0:483:509d:729b]) (user=aliceryhl job=prod-delivery.src-stubby-dispatcher) by 2002:a05:600c:6091:b0:477:df7:b020 with SMTP id 5b1f17b1804b1-4839e661d1bmr99895665e9.18.1771574516871; Fri, 20 Feb 2026 00:01:56 -0800 (PST) Date: Fri, 20 Feb 2026 08:01:56 +0000 In-Reply-To: Mime-Version: 1.0 References: <29e454bc-5a46-43b2-80b0-4d8d93e3feae@zohomail.in> Message-ID: Subject: Re: [RFC] mm/vmalloc: vrealloc() shrink TODO - seeking direction before implementing From: Alice Ryhl To: Danilo Krummrich Cc: Uladzislau Rezki , Shivam Kalra , linux-mm@kvack.org, akpm@linux-foundation.org Content-Type: text/plain; charset="utf-8" X-Rspam-User: X-Rspamd-Server: rspam06 X-Rspamd-Queue-Id: 9F318C000B X-Stat-Signature: eakzbcpnfkiqr13heh6qiymxaxbfuff7 X-HE-Tag: 1771574518-161063 X-HE-Meta: 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 Ua6zgRO0 kJSf70bcecUNS4wiBGjdJ/X8yZ/C57xL9rWKUGZTXw0FF96U9QMm5TDwq+DyQTYavu4ITI/zTLmIKUqTK5k9M9uUs8r7xffU8xJZ6DcA+FviSxverukLdUTTroHujdOUiv19YRvnTlLTlFKR5Lr1C5vABsdA5o131JK9p6Co2i6rtrIr+R93IKy8N1RvxBmnJZpp2/9yCWiDURjls4Ne9VtOqO2pR713RJbvm0SmSv+KbZHq5LABwV9YakMli47F+kkLQy8RIoBFaddQeLr/bfy7L1tlR5TGozjS85TLOMG02Xq7oUVbISjOY3Qt0vNLoKA5a4ZiBrJ8azliFWwf/Oc08SyHpV4yDKKybYL6XCjS3hmfceEMgA6bPJ18wIwKPRd3l4wr15XY3nqQy+gyF+AHZjGWn64h3B51YxbqiMMz3Ju4WczpT9iSaPWSyYFnpWIksSSxJziIR6tUO7AVzPZNw/bBRHv/8gfSruYl1ZEBbFULqy9463wKYfH8H+JD3CRsywAA0skb0OJTut10QPXP1ezwtepb3iD6zD2uDrKTuo0XIIREIKppTnbvkMkga2DF7 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 Thu, Feb 19, 2026 at 06:01:29PM +0100, Danilo Krummrich wrote: > (Cc: Alice) > > On Thu Feb 19, 2026 at 5:57 PM CET, Uladzislau Rezki wrote: > > I think we have 0 users of vrealloc(). It was added because of Rust folk > > wanted this. > > We just gained a user with the Rust binder driver. Yeah, if I have a long-lived resizable array (allocated with kvmalloc) then I'd like to be able to shrink it if the number of elements decrease again, to prevent unnecessary indefinite memory usage. Alice