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[213.95.11.211]) by mx.google.com with ESMTPS id 188si2433864wmd.156.2019.06.04.00.26.36 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 04 Jun 2019 00:26:36 -0700 (PDT) Received-SPF: pass (google.com: best guess record for domain of hch@lst.de designates 213.95.11.211 as permitted sender) client-ip=213.95.11.211; Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of hch@lst.de designates 213.95.11.211 as permitted sender) smtp.mailfrom=hch@lst.de 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) 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: 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.