Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753862AbdLMUqc (ORCPT ); Wed, 13 Dec 2017 15:46:32 -0500 Received: from mail.free-electrons.com ([62.4.15.54]:46747 "EHLO mail.free-electrons.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752908AbdLMUqa (ORCPT ); Wed, 13 Dec 2017 15:46:30 -0500 Date: Wed, 13 Dec 2017 21:46:28 +0100 From: Boris Brezillon To: Colin Ian King Cc: Richard Weinberger , David Woodhouse , Brian Norris , Marek Vasut , Cyrille Pitchen , linux-mtd@lists.infradead.org, kernel-janitors@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH][mtd-next] mtd: nand: remove redundant check of len Message-ID: <20171213214628.1e1c1431@bbrezillon> In-Reply-To: <20171213213844.78efe253@bbrezillon> References: <20171213201743.27324-1-colin.king@canonical.com> <20171213212425.6fe999cb@bbrezillon> <20171213213844.78efe253@bbrezillon> X-Mailer: Claws Mail 3.14.1 (GTK+ 2.24.31; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1268 Lines: 41 On Wed, 13 Dec 2017 21:38:44 +0100 Boris Brezillon wrote: > On Wed, 13 Dec 2017 20:30:04 +0000 > Colin Ian King wrote: > > > On 13/12/17 20:24, Boris Brezillon wrote: > > > On Wed, 13 Dec 2017 20:17:43 +0000 > > > Colin King wrote: > > > > > >> From: Colin Ian King > > >> > > >> The check of len being zero is redundant as it has already been > > >> sanity checked for this value at the start of the function. Hence > > >> it is impossible for this test to be true and so the redundant > > >> code can be removed. > > > > > > Nope, it's not the same test, the initial test is > > > > > > if (len && !buf) > > > > Ah, the current tip from linux-next has: > > > > 1912 if (!len || !buf) > > 1913 return -EINVAL; > > > > ..so I guess that's why it got picked up by static analysis. > > Hm, that's weird, that's not what I see [1] in linux-next. This being said, the test in nand_readid_op() is wrong [1], so maybe this was the thing you were trying to fix. No need to send a new patch, I'll squash the fix in the commit introducing the function. Thanks, Boris [1]http://code.bulix.org/kxivhd-240572