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]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id ED710CCF9F0 for ; Wed, 29 Oct 2025 16:09:38 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id D6BBB8E00A9; Wed, 29 Oct 2025 12:09:25 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id D434C8E0045; Wed, 29 Oct 2025 12:09:25 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id C58B38E00A9; Wed, 29 Oct 2025 12:09:25 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0014.hostedemail.com [216.40.44.14]) by kanga.kvack.org (Postfix) with ESMTP id A6C1A8E0045 for ; Wed, 29 Oct 2025 12:09:25 -0400 (EDT) Received: from smtpin16.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay04.hostedemail.com (Postfix) with ESMTP id 475691A083C for ; Wed, 29 Oct 2025 16:09:25 +0000 (UTC) X-FDA: 84051636690.16.EBE02E7 Received: from mail-qk1-f176.google.com (mail-qk1-f176.google.com [209.85.222.176]) by imf09.hostedemail.com (Postfix) with ESMTP id 40F5D140012 for ; Wed, 29 Oct 2025 16:09:23 +0000 (UTC) Authentication-Results: imf09.hostedemail.com; dkim=pass header.d=ziepe.ca header.s=google header.b=P5c4sRsa; spf=pass (imf09.hostedemail.com: domain of jgg@ziepe.ca designates 209.85.222.176 as permitted sender) smtp.mailfrom=jgg@ziepe.ca; dmarc=none ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1761754163; 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: in-reply-to:in-reply-to:references:references:dkim-signature; bh=ra6gE4GNLdWG7Tqyy4+9etzH3tIuFsSBjp83q0VcDV0=; b=jvCFsNMgu348p/EvgwXEtxQzFPp5NVxYU1Km0sCRRaypzcqxAweeAOqodL3Hrd1iXTiXCL BXTnM6jXHd1yNLJ6vri9tzG48Q7q9p6RA2xIbGEjWK4pr5i+qwzagOTZDX7GI8RWKCV+ix Jay/ZsBFPC3HcWxvbeV1OUAg+uWjtSs= ARC-Authentication-Results: i=1; imf09.hostedemail.com; dkim=pass header.d=ziepe.ca header.s=google header.b=P5c4sRsa; spf=pass (imf09.hostedemail.com: domain of jgg@ziepe.ca designates 209.85.222.176 as permitted sender) smtp.mailfrom=jgg@ziepe.ca; dmarc=none ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1761754163; a=rsa-sha256; cv=none; b=z26IxpfOQJQbAQC5qnUUB5b2DvpuvDao+DRrMsTvTNNVriv28EX/LBGtMkEoWuh7TvNRWB SdKf/ADI04P7kGIbGVJYHQjD6Odief/uaPvFZHL7m2OiFj1bnnlXc6/IfQuHhSn0MuYIzK B7YzCHmZByF12bFOmKuE8Z5W+zKpksk= Received: by mail-qk1-f176.google.com with SMTP id af79cd13be357-88f2aebce7fso762084485a.3 for ; Wed, 29 Oct 2025 09:09:22 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ziepe.ca; s=google; t=1761754162; x=1762358962; darn=kvack.org; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:from:to:cc:subject:date:message-id:reply-to; bh=ra6gE4GNLdWG7Tqyy4+9etzH3tIuFsSBjp83q0VcDV0=; b=P5c4sRsaiKlzEJrLKubHF3ixd49fJCqClR/xacKUuihCYiSwvOC1L0ayBoblaEmMld +Z8TFrypD6gtbswKqFX5MF3A5vpnjGUDue80LdSa6MaCwqhUktLBo5LDC2HQ1uff2opq iVFHDOIAZFuD/uW2oLY9LPr8/rAMp4vUOAKsNqBNhoVHZdBgnElbOUQg4hZfPQv8/bQO QM3r975zgzS1ag/BYAs9SbDVk5tPwGiLug/zUF/abhSL8x84PDVtm2fEJGfGv3QjaP7k nOS0bBsShQmnTHkHsRvuZw7SDfa6n5K4pmytbQ7hjA3cwEAQht9BoQfk6xaofat/jI5D N3MA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1761754162; x=1762358962; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=ra6gE4GNLdWG7Tqyy4+9etzH3tIuFsSBjp83q0VcDV0=; b=LEQLaxTJkpubFtJBTVe+FI1aCzBT3xtvL+wuxmYSAoP3sp4fe/13Pc+6Fj9NpVdLKq 4nCnBy/F7BtBlT7pl08T6P8t6SMMCM2fo/c4f4Hr2c9JC1MiAUOlHToMlCM2Vlcg2JyU VF2CyiE+lEURaZS8jSJcrfdsgLZEB4OYvgRYs8b3IAuhKFfxPlzAx6G9AQJjXdlxiqiJ wRLLH0biimZ+sEqqZgm7RhW/7GuHNCThW+FmGfvJxagR0JI73yAkkPQCiIEuSTy7GCiS XdrV2CoELYDK3Jxav8NIS74LNI1Wem6QFqORsD5SSh5hQZqFadtev1ZyaVP2rNuZuFRb PnmQ== X-Forwarded-Encrypted: i=1; AJvYcCUb5MlYCi1EzaoOgu76xdRYfocl86lRt7dMEWo5GBDhoD2H2D5iEWWJVPsEkVcmfNlLPbfL0iCLMQ==@kvack.org X-Gm-Message-State: AOJu0YzKHjmOFX25d2WVgUpsoNxXvAOYDYxR71/YuVsOtg+O4rXVzNt7 u3+tRbGzrYbjnxA1S1nOXllWADlTo4wpOCm4V1UQp4TeNl8iRXP4WPoUx++yolDYgFY= X-Gm-Gg: ASbGnctrRBa+eRqFW17a2ykQ8gkgPVZ6sv20rdChHMvO3Bd9TA0a+7bEFm4bxMWyK0F vTwa1MLsAb972a8qm/zJtDfT+pcyPqiRdlWMDYclh4l51OVHIrO0Vjs503mIvuMwq2kDk86DEWr R8zyml52wBJj1nf2K317yWhko5tUdwTTJdi9Gw3xxiepM7/U2fGTDJAuJHwAfMIVp1phc7Atpos AA53p2O9xT6BtI6RjTWxjWIUzO+TQg/bC6a1VHl5lXV2udtascu5c1lh1Pp2I/W6awA4L/JKxXM quXYshXoJI5zqEWwrrjirCQPEu5zntRX6gUPRpDx9dU566eZWfuY8MXQCF7IVCAwCV15ZnS+UP7 uX+8qJQ5iGSOvDo5DAOuJl+SLTK+MoUrdgimWOWAgWakAJ60bVbAiOp2RyC/+n7amnREsZX3Lcu 9BBrazRbGd7tNKPa3E413SfeEA5I4mlKCspBV9unPyrjrDhA== X-Google-Smtp-Source: AGHT+IF6rFnidmIfY6Ro1wANLijusetvx4ngsO9eh8sfxCbTUwpnkArLo2xTU45YJpn8RBXsZSHBbA== X-Received: by 2002:a05:620a:19a5:b0:866:73f7:25a2 with SMTP id af79cd13be357-8a8ef52d830mr451427585a.64.1761754162225; Wed, 29 Oct 2025 09:09:22 -0700 (PDT) Received: from ziepe.ca (hlfxns017vw-47-55-120-4.dhcp-dynamic.fibreop.ns.bellaliant.net. [47.55.120.4]) by smtp.gmail.com with ESMTPSA id af79cd13be357-89f254a41cdsm1078205885a.29.2025.10.29.09.09.21 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 29 Oct 2025 09:09:21 -0700 (PDT) Received: from jgg by wakko with local (Exim 4.97) (envelope-from ) id 1vE8jh-00000004ztF-0Awe; Wed, 29 Oct 2025 13:09:21 -0300 Date: Wed, 29 Oct 2025 13:09:21 -0300 From: Jason Gunthorpe To: Pasha Tatashin Cc: David Matlack , akpm@linux-foundation.org, brauner@kernel.org, corbet@lwn.net, graf@amazon.com, linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-mm@kvack.org, masahiroy@kernel.org, ojeda@kernel.org, pratyush@kernel.org, rdunlap@infradead.org, rppt@kernel.org, tj@kernel.org, jasonmiu@google.com, skhawaja@google.com Subject: Re: [PATCH v3 1/3] liveupdate: kho: warn and fail on metadata or preserved memory in scratch area Message-ID: <20251029160921.GP760669@ziepe.ca> References: <20251021000852.2924827-1-pasha.tatashin@soleen.com> <20251021000852.2924827-2-pasha.tatashin@soleen.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Rspamd-Server: rspam12 X-Rspamd-Queue-Id: 40F5D140012 X-Stat-Signature: c6s36h9yixhuejir1mw7pprmy1jfr8bj X-Rspam-User: X-HE-Tag: 1761754163-733135 X-HE-Meta: U2FsdGVkX1940UJsry8vNLv3VV5YEn9TPN/ybCs3+ImftuXwznFCxYKm7/2iZjXGcjY9lWUX2NWPTRbnE3VBfpheihsmYQu64CWOYpgPj5iMyIgVAZp+rkMG1jPwC+pqWVe/JdtyBH6zU7/HTc29JzwAjHS5N9R/dFcdaYc3WnksNi5DWtem5n9RbzY3TzwGKvBQY7zcQezEoHJXGHj8fHnRd7fEYFFMqKdOSz04iivyDIh6hlxK2rck385h2cxMtwxdHIlh5buSLoYP01+bBZMU4LHprMFKa6ZxzrjseCW8TIaGUVeWqwXY0tCwLshxMaOT96FIofyDDd7JpNDE1sEursNf5jTa0WQ664Zllkan69qWs/x39Gprx9Q68O8dvv06xjk6e5QxpK8DQJ6pnXPquQIGHwJZbNMczicDMcAGAG10kX030BXd392YXdxzljBVTtUfoJxarD3lVALU5QxJhRyxgEvGyvqXKeN7PK3C8DfPGYYMxynsAXKzb4dhbwcLbtbQT/EkiXkLcBlqm/hUtPtEMKb4LYoylQsrsfYUJNTYgnTLyS2mzNak9hGEhThLT8nVnXGZAgFulBlUwrbhT27DlZXB6V+9emFG3IZNVZkgT3rZgTQ8MdL3W40GffZkNV/bXZ6CTiMlsCsoSLfmNMH6lEkWPee7oBTmKk19A7jWdf0KHbZwz41M3TsFiBJRt7t5I6duxUglsVKVBFZWND01IcBbjkquqZSTLiaKc02yI/yxNFX24V+TDrVwRy9MZ2yIl1MIMCtZBTuM0vIRKlyUgTzzOV13oQRf5KZAvwHqEctfPiuZcW6NVWtxKR3YHD2Fm+C6ghNkh7lde88w5Ef067D9/Uj71mQ0biAuSThLZ73ljF0hFBOgzmZD1M3YbZ7AekYfWRMllpZjc/Bc6cAngtB9F8+aCu+l2B1NggHTUcAi41uCMrspJRIdbvuQ8P3GdLQomDO5fy5 8r9FxR17 7zvVjARcrwQDdQ1oRjhsZ/pNydoDo9frhFrPzDQu3qbsRFP8/ZHUrd014SWM6KPiDWn9LrYWugOqOeVA99Peq/uiwN1IVDIRZV0ZgrlJLDiEKvtkIRerczqcKu2AE8JnqtodQ4aQtd1Pc9SfjwcXu6jeNRdhko6lXZe52Aq8j/rd+wG/7y5DKE7KXAdpWZux/kwuvsIhp/07SUtmuIpl02X3WffzQhDaDtVqM9UitojrRnHZmW+y1Mix60A== 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, Oct 27, 2025 at 08:01:59PM -0400, Pasha Tatashin wrote: > > > static void *xa_load_or_alloc(struct xarray *xa, unsigned long index, size_t sz) > > > { > > > - void *elm, *res; > > > + void *res = xa_load(xa, index); > > > > > > - elm = xa_load(xa, index); > > > - if (elm) > > > - return elm; > > > + if (res) > > > + return res; > > > + > > > + void *elm __free(kfree) = kzalloc(sz, GFP_KERNEL); > > > > nit: This breaks the local style of always declaring variables at the > > beginning of blocks. > > I think this suggestion came from Mike, to me it looks alright, as it > is only part of the clean-up path. It is the recommended style for using cleanup.h stuff, declare and assign in one statement. Jason