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 X-Spam-Level: X-Spam-Status: No, score=-2.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id A74A6C433DF for ; Fri, 3 Jul 2020 15:46:39 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 80BA720884 for ; Fri, 3 Jul 2020 15:46:39 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="F2LHPoy/" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726418AbgGCPqi (ORCPT ); Fri, 3 Jul 2020 11:46:38 -0400 Received: from us-smtp-2.mimecast.com ([207.211.31.81]:29134 "EHLO us-smtp-delivery-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726035AbgGCPqh (ORCPT ); Fri, 3 Jul 2020 11:46:37 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1593791195; h=from:from: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; bh=kZamksu9q4RTlXzhEF7oeFMOgoJ1Qb6qWkOIgdiQa7I=; b=F2LHPoy/ikCLvo0s1d72nWd28RN64dszEs7ihUpMT/FcwiSvjN3iGuwsoIq0MHsTmYJavi wQrl0nyPHGQaEAFAfg0Ok3LTsZ4V66QXRWa1VOkhn1fiS9Oyt7/h/AKrDBLoC87U3TYVH7 F14PHyOj8vJSfWZAnEdX3uTXlCNg5W4= Received: from mail-qv1-f69.google.com (mail-qv1-f69.google.com [209.85.219.69]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-227-qyKEGxILOF26Ily46xh4yQ-1; Fri, 03 Jul 2020 11:46:34 -0400 X-MC-Unique: qyKEGxILOF26Ily46xh4yQ-1 Received: by mail-qv1-f69.google.com with SMTP id r19so20686082qvz.7 for ; Fri, 03 Jul 2020 08:46:34 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-transfer-encoding :content-language; bh=kZamksu9q4RTlXzhEF7oeFMOgoJ1Qb6qWkOIgdiQa7I=; b=ZENqXioCIEkm27aeRWgRL+epKFkqG/f6Tg1l/weme7hqT+6nguV1XE/dS2d/mhr0xL FcuehKw5bGmcseSUXhvJv4UNOD53lXfsG63M38eZAe+qqVzlzRhxDXToSKrGG1s/dSgM UObOAQiqskWUdGrKpa0n0lYHef3Ie1NENHuFOZcRsO5vzPa7Ho67QRqWyqfkcCC76Xb4 HhYroL4skeWTVpLUjAAEcLpioKscgCbkNYCuZlh8nkFvMNet5A6Ti+9EymvMUs1P2YVd pU/QLcBg3G+6tzoSmnxalUHoj3DiYg6Z5UYBNvJlbw86Rm4OPNpb174mr3uCXE8Jd8Q6 ycow== X-Gm-Message-State: AOAM532nfr14GJQT9WHujJkbHYthHdT9PcxzUglNwqyvgHGBMuNiF6oe 4CsndrQy8oTcZm3yGYghkpo8K6VwQKz2zZehufjDxYzUqL3Mg91EBINJgYQCsrXK/siCwrCOu/J xB9ar8iiKwct5QhkS250F87GF X-Received: by 2002:a05:6214:884:: with SMTP id cz4mr21705039qvb.3.1593791193268; Fri, 03 Jul 2020 08:46:33 -0700 (PDT) X-Google-Smtp-Source: ABdhPJwPFteIG/zDmV9OhkFZB+1yp9sGcAuhAQc+YY9Q88SZ8CcE37BbpMKtTkvgBPVirzToeV7QFw== X-Received: by 2002:a05:6214:884:: with SMTP id cz4mr21705023qvb.3.1593791193050; Fri, 03 Jul 2020 08:46:33 -0700 (PDT) Received: from trix.remote.csb (075-142-250-213.res.spectrum.com. [75.142.250.213]) by smtp.gmail.com with ESMTPSA id k45sm13334427qtc.62.2020.07.03.08.46.31 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Fri, 03 Jul 2020 08:46:32 -0700 (PDT) Subject: Re: [PATCH] mm: initialize return of vm_insert_pages To: Matthew Wilcox Cc: akpm@linux-foundation.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org References: <20200703145202.10629-1-trix@redhat.com> <20200703145454.GH25523@casper.infradead.org> From: Tom Rix Message-ID: <7b6eb14b-bbdc-dedb-c989-5e705cb9a453@redhat.com> Date: Fri, 3 Jul 2020 08:46:30 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.6.0 MIME-Version: 1.0 In-Reply-To: <20200703145454.GH25523@casper.infradead.org> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Content-Language: en-US Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 7/3/20 7:54 AM, Matthew Wilcox wrote: > On Fri, Jul 03, 2020 at 07:52:02AM -0700, trix@redhat.com wrote: >> From: Tom Rix >> >> clang static analysis reports a garbage return >> >> In file included from mm/memory.c:84: >> mm/memory.c:1612:2: warning: Undefined or garbage value returned to caller [core.uninitialized.UndefReturn] >> return err; >> ^~~~~~~~~~ >> >> The setting of err depends on a loop executing. >> So initialize err. > I'd argue that returning zero is wrong. If someone's asked to insert > zero pages, that's a nonsense thing to do so it should return -EINVAL.. > good point, i'll respin.