From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id EDEA0C3DA70 for ; Tue, 23 Jul 2024 01:43:57 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 5C89C6B0083; Mon, 22 Jul 2024 21:43:57 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 502F66B0085; Mon, 22 Jul 2024 21:43:57 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 37B666B0088; Mon, 22 Jul 2024 21:43:57 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0016.hostedemail.com [216.40.44.16]) by kanga.kvack.org (Postfix) with ESMTP id 1A93E6B0083 for ; Mon, 22 Jul 2024 21:43:57 -0400 (EDT) Received: from smtpin03.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay06.hostedemail.com (Postfix) with ESMTP id AA03BA4EB0 for ; Tue, 23 Jul 2024 01:43:56 +0000 (UTC) X-FDA: 82369321272.03.38DC807 Received: from sin.source.kernel.org (sin.source.kernel.org [145.40.73.55]) by imf08.hostedemail.com (Postfix) with ESMTP id 73D7A160007 for ; Tue, 23 Jul 2024 01:43:54 +0000 (UTC) Authentication-Results: imf08.hostedemail.com; dkim=pass header.d=linux-foundation.org header.s=korg header.b=PVTXrXJ0; spf=pass (imf08.hostedemail.com: domain of akpm@linux-foundation.org designates 145.40.73.55 as permitted sender) smtp.mailfrom=akpm@linux-foundation.org; dmarc=none ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1721699011; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=wg3k2iVz70OYPCj5CxfQ8xAFNgGAtL1aR4xjPGcgJI4=; b=SvABMwlzKmqMdLooTGLT0cH/htv1HrQja32UyO9L6sjRVejLIYSJjA/2GpACAf6tDR8iYv vc9j3lUV0em8PAVrURUxDX4Bs5LmhRdpNxnfsOWiS2XWKtKLDiiWeq3IFJddYA+afbYn8x SmrQcxcU4g1CxzffmtUZ3BAB5HFuGdo= ARC-Authentication-Results: i=1; imf08.hostedemail.com; dkim=pass header.d=linux-foundation.org header.s=korg header.b=PVTXrXJ0; spf=pass (imf08.hostedemail.com: domain of akpm@linux-foundation.org designates 145.40.73.55 as permitted sender) smtp.mailfrom=akpm@linux-foundation.org; dmarc=none ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1721699011; a=rsa-sha256; cv=none; b=d5taxB/mmvczX+3DpyRUvbptXF88pYCeCs8D3wL46qPWE6scYoXi+B+Lk5Uk0D0Ctn0giL XJ/P0MTc+5sv0k7AaJv0NkLbBget8tCEO3xulW5HiOqV3KZvA5icIze2IWG1EJp/6eqyK0 fdQ7D2VNtkQ3gEQQMiTwjF1Y6lU0m30= Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by sin.source.kernel.org (Postfix) with ESMTP id D9D39CE0C51; Tue, 23 Jul 2024 01:43:50 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id B9A4DC116B1; Tue, 23 Jul 2024 01:43:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1721699029; bh=uLE4/Kk/lWZmHiZavjPUPKJ4gYq6j64EmWnd8S2dSew=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=PVTXrXJ0noRS7iTqzd+vPAnX0VHUg2MDw3tsmuDzh9F7od1olKPkNiUtapKIHv3WW 3Mr7XTwhNkRmuyaJwdSjzpY7+lS9raO/zWCTZ4Uiby3NGcUG6NBeI9bQRsxhsaZ2Hr 7RrlQ+LBwT8c0S+Hdi+4JqJqFnDc/nilJ6pCgxow= Date: Mon, 22 Jul 2024 18:43:48 -0700 From: Andrew Morton To: Danilo Krummrich Cc: cl@linux.com, penberg@kernel.org, rientjes@google.com, iamjoonsoo.kim@lge.com, vbabka@suse.cz, roman.gushchin@linux.dev, 42.hyeyoo@gmail.com, urezki@gmail.com, hch@infradead.org, kees@kernel.org, ojeda@kernel.org, wedsonaf@gmail.com, mhocko@kernel.org, mpe@ellerman.id.au, chandan.babu@oracle.com, christian.koenig@amd.com, maz@kernel.org, oliver.upton@linux.dev, linux-kernel@vger.kernel.org, linux-mm@kvack.org, rust-for-linux@vger.kernel.org Subject: Re: [PATCH v2 2/2] mm: kvmalloc: align kvrealloc() with krealloc() Message-Id: <20240722184348.3df3b433c8f49f123e1c8d9e@linux-foundation.org> In-Reply-To: <20240722163111.4766-3-dakr@kernel.org> References: <20240722163111.4766-1-dakr@kernel.org> <20240722163111.4766-3-dakr@kernel.org> X-Mailer: Sylpheed 3.8.0beta1 (GTK+ 2.24.33; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Rspamd-Server: rspam11 X-Rspamd-Queue-Id: 73D7A160007 X-Stat-Signature: s15616b5ji79dw5s7ft4ojqk49f5g4rz X-Rspam-User: X-HE-Tag: 1721699034-953113 X-HE-Meta: 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 EZA2mBJH fYnXpnjeJyUskLjYo+LRSuIKyksYCxgiuJ49vPsfYVm/oqCneTyVZ4WMw9UeG0PIzg6Fi0tsgG3gRWRnxNd1qigJGZGaiTagnAHjBUasRsASuh6OYxopyQofTLCjXWrumt9rmMg3tAv+CyS9Xd4ImrDLprMiHlenBHsHFZFRpZgVOAEyPbC2pkfwtICQnjYlWPKYfuAP7UHcZMh5D3JFKPpTnKsapDXJKlwdaZcwxvw28+YuTEcmeviKGjM5ZkyHI5BYjTVPRoxEfJytN0MbE4rxL9RYhAU1yjX+ht5iLRrokEPUTos5OzmCcR96ZzCaMU2cjyfLWbvyXyIJX7z5BsfPL9SmsMgbyfEGl/PcUMb+ne6SSY3aQIp+sCLKUUNZK3ws7zSPjTDcDDDpphBdP5Uv1pg== 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 Mon, 22 Jul 2024 18:29:24 +0200 Danilo Krummrich wrote: > Besides the obvious (and desired) difference between krealloc() and > kvrealloc(), there is some inconsistency in their function signatures > and behavior: > > - krealloc() frees the memory when the requested size is zero, whereas > kvrealloc() simply returns a pointer to the existing allocation. The old kvrealloc() behavior actually sounds somewhat useful. You've checked that no existing sites were relying on this? And that all existing kvrealloc() callers were (incorrectly) checking for NULL? Seems that way.