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=-0.9 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=ham 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 D7231C28CC1 for ; Sat, 1 Jun 2019 10:41:14 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A852F271ED for ; Sat, 1 Jun 2019 10:41:14 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="rjoKGRLL" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726989AbfFAKlN (ORCPT ); Sat, 1 Jun 2019 06:41:13 -0400 Received: from mail-lj1-f194.google.com ([209.85.208.194]:42005 "EHLO mail-lj1-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726109AbfFAKlN (ORCPT ); Sat, 1 Jun 2019 06:41:13 -0400 Received: by mail-lj1-f194.google.com with SMTP id t28so837605lje.9 for ; Sat, 01 Jun 2019 03:41:12 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=HfG8SFYlwhX2T6RV6yxB9+NDJcpkM3O1MaSrYiv8LPo=; b=rjoKGRLLtJKt2NLllelbm573MDL2ykr+faYahdLKjSY7Y5bcl9oOcfgIPjxjLRT8Rg mveZbNR6/4PcibX5IGuiP2ht/kulnh3WcI4MaWK2Y1A0DXjutsYEwD3qTftFhiv8GqfK 7+qaDof1ZYd3doX7X1h+7WeRcfHVpsj0pwMdcoQ9xEdSqbExbR0q5XsGZkhOjNfO0bju T5gSSanCNIC12PTxtOjXIjZmgaW8TSijlkhgbcIQjczBFFhQDLrsYZl8VwB/3MG1Gh3c 8YfiZYGEuJBRTypFu7XSl1WsefQ2ppNKSDi5woINqma62CXA6zpRINHHLvZ5yGrTw5X8 DUHQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=HfG8SFYlwhX2T6RV6yxB9+NDJcpkM3O1MaSrYiv8LPo=; b=ESFbTMWKWNsQZtw8LzlXnfkJeb311AJdEHRp+7wQkvvSm9JrZYa3RfDgMf1LexO4Mk 6Pb6Zj+joCRrCSK+OHtIrz4cNKwiOianfVjLkfnNogSM3no5PT3zLEiNdn/tR0OiZiBg 9vvq0gKM0HFnR9oJ7KleKsCmsHhwRlzhcW4Ys7vj8ppJNsOcoj1jN/NGvobD5aAs1MDL IOKVcUtaCnFmyeBRUA0vMjsVoBRfSE/XmfHuutjNr3ayOA0Iz5SHZLh2ELgwhW1GJWnp tXYXB9eUoZCLEnvK/kuvH1zmRAk5d1Pw1b0WFzYUts4S+JiUi9UCQPHlzYVNdj1chfCk CkfQ== X-Gm-Message-State: APjAAAUDJJiQzyM7V0fQ9ORjw11KTVz8d9QuQyPR3WDE5dphuSIf31rW eQQSQfsM62PwIXsCXmRh3/7OyArGWUazOo3r8To= X-Google-Smtp-Source: APXvYqwo+hRPRQiNwv/GCJLziYFhPRmDBka35PISCOCnRhr43lAq1JZzc9/8GlGwArLsGmyrafsMQ15XfcxCKdwIxNE= X-Received: by 2002:a2e:9157:: with SMTP id q23mr8892650ljg.188.1559385671552; Sat, 01 Jun 2019 03:41:11 -0700 (PDT) MIME-Version: 1.0 References: <20190528193004.GA7744@gmail.com> In-Reply-To: From: Miguel Ojeda Date: Sat, 1 Jun 2019 12:41:00 +0200 Message-ID: Subject: Re: [PATCH] mm: Fail when offset == num in first check of vm_map_pages_zero() To: Souptick Joarder , Andrew Morton Cc: Matthew Wilcox , Peter Zijlstra , =?UTF-8?B?SsOpcsO0bWUgR2xpc3Nl?= , "Aneesh Kumar K.V" , Huang Ying , open list , Linux-MM Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, May 29, 2019 at 9:09 AM Souptick Joarder wrote: > > On Wed, May 29, 2019 at 1:38 AM Miguel Ojeda > wrote: > > > > If the user asks us for offset == num, we should already fail in the > > first check, i.e. the one testing for offsets beyond the object. > > > > At the moment, we are failing on the second test anyway, > > since count cannot be 0. Still, to agree with the comment of the first > > test, we should first there. > > I think, we need to cc linux-mm. Cc'ing Andrew as well as Souptick suggested me. Cheers, Miguel