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=-2.5 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_MUTT autolearn=unavailable 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 A9272C282CE for ; Tue, 4 Jun 2019 07:26:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8B98B24AEC for ; Tue, 4 Jun 2019 07:26:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726840AbfFDH0i (ORCPT ); Tue, 4 Jun 2019 03:26:38 -0400 Received: from verein.lst.de ([213.95.11.211]:33768 "EHLO newverein.lst.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726589AbfFDH0i (ORCPT ); Tue, 4 Jun 2019 03:26:38 -0400 Received: by newverein.lst.de (Postfix, from userid 2407) id 89A2368B02; Tue, 4 Jun 2019 09:26:10 +0200 (CEST) Date: Tue, 4 Jun 2019 09:26:10 +0200 From: Christoph Hellwig To: Linus Torvalds Cc: Christoph Hellwig , Paul Burton , James Hogan , Yoshinori Sato , Rich Felker , "David S. Miller" , Nicholas Piggin , Khalid Aziz , Andrey Konovalov , Benjamin Herrenschmidt , Paul Mackerras , Michael Ellerman , linux-mips@vger.kernel.org, Linux-sh list , sparclinux@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, Linux-MM , the arch/x86 maintainers , Linux List Kernel Mailing Subject: Re: [PATCH 03/16] mm: simplify gup_fast_permitted Message-ID: <20190604072610.GE15680@lst.de> References: <20190601074959.14036-1-hch@lst.de> <20190601074959.14036-4-hch@lst.de> <20190603074121.GA22920@lst.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.17 (2007-11-01) Sender: linux-mips-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-mips@vger.kernel.org On Mon, Jun 03, 2019 at 10:02:10AM -0700, Linus Torvalds wrote: > On Mon, Jun 3, 2019 at 9:08 AM Linus Torvalds > wrote: > > > > The new code has no test at all for "nr_pages == 0", afaik. > > Note that it really is important to check for that, because right now we do True. The 0 check got lost. I'll make sure we do the right thing for the next version. From mboxrd@z Thu Jan 1 00:00:00 1970 From: Christoph Hellwig Date: Tue, 04 Jun 2019 07:26:10 +0000 Subject: Re: [PATCH 03/16] mm: simplify gup_fast_permitted Message-Id: <20190604072610.GE15680@lst.de> List-Id: References: <20190601074959.14036-1-hch@lst.de> <20190601074959.14036-4-hch@lst.de> <20190603074121.GA22920@lst.de> In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Linus Torvalds Cc: Christoph Hellwig , Paul Burton , James Hogan , Yoshinori Sato , Rich Felker , "David S. Miller" , Nicholas Piggin , Khalid Aziz , Andrey Konovalov , Benjamin Herrenschmidt , Paul Mackerras , Michael Ellerman , linux-mips@vger.kernel.org, Linux-sh list , sparclinux@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, Linux-MM , the arch/x86 maintainers , Linux List Kernel Mailing On Mon, Jun 03, 2019 at 10:02:10AM -0700, Linus Torvalds wrote: > On Mon, Jun 3, 2019 at 9:08 AM Linus Torvalds > wrote: > > > > The new code has no test at all for "nr_pages = 0", afaik. > > Note that it really is important to check for that, because right now we do True. The 0 check got lost. I'll make sure we do the right thing for the next version. 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=-2.5 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_MUTT autolearn=unavailable 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 4DC26C282CE for ; Tue, 4 Jun 2019 07:28:16 +0000 (UTC) Received: from lists.ozlabs.org (lists.ozlabs.org [203.11.71.2]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 0A0B124708 for ; Tue, 4 Jun 2019 07:28:15 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 0A0B124708 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=lst.de Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Received: from lists.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 45J3Rx6Wk7zDqWY for ; Tue, 4 Jun 2019 17:28:13 +1000 (AEST) Authentication-Results: lists.ozlabs.org; spf=none (mailfrom) smtp.mailfrom=lst.de (client-ip=213.95.11.211; helo=newverein.lst.de; envelope-from=hch@lst.de; receiver=) Authentication-Results: lists.ozlabs.org; dmarc=none (p=none dis=none) header.from=lst.de Received: from newverein.lst.de (verein.lst.de [213.95.11.211]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 45J3Q710ZszDqNS for ; Tue, 4 Jun 2019 17:26:39 +1000 (AEST) Received: by newverein.lst.de (Postfix, from userid 2407) id 89A2368B02; Tue, 4 Jun 2019 09:26:10 +0200 (CEST) Date: Tue, 4 Jun 2019 09:26:10 +0200 From: Christoph Hellwig To: Linus Torvalds Subject: Re: [PATCH 03/16] mm: simplify gup_fast_permitted Message-ID: <20190604072610.GE15680@lst.de> References: <20190601074959.14036-1-hch@lst.de> <20190601074959.14036-4-hch@lst.de> <20190603074121.GA22920@lst.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.17 (2007-11-01) X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Rich Felker , Yoshinori Sato , Linux-sh list , James Hogan , the arch/x86 maintainers , Khalid Aziz , Nicholas Piggin , "David S. Miller" , Linux-MM , Paul Burton , Paul Mackerras , Andrey Konovalov , sparclinux@vger.kernel.org, linux-mips@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, Christoph Hellwig , Linux List Kernel Mailing Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" On Mon, Jun 03, 2019 at 10:02:10AM -0700, Linus Torvalds wrote: > On Mon, Jun 3, 2019 at 9:08 AM Linus Torvalds > wrote: > > > > The new code has no test at all for "nr_pages == 0", afaik. > > Note that it really is important to check for that, because right now we do True. The 0 check got lost. I'll make sure we do the right thing for the next version.