Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756503AbaGVTMn (ORCPT ); Tue, 22 Jul 2014 15:12:43 -0400 Received: from mail-vc0-f182.google.com ([209.85.220.182]:62699 "EHLO mail-vc0-f182.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751185AbaGVTMl convert rfc822-to-8bit (ORCPT ); Tue, 22 Jul 2014 15:12:41 -0400 MIME-Version: 1.0 In-Reply-To: <1406055834.23587.1.camel@gmail.com> References: <1406055834.23587.1.camel@gmail.com> Date: Tue, 22 Jul 2014 21:12:40 +0200 Message-ID: Subject: Re: [RFC] 3.16-rc6 -- fs/direct-io.c:1011 from and to uninitialized. From: Richard Weinberger To: Ian Kumlien Cc: "linux-kernel@vger.kernel.org" Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Jul 22, 2014 at 9:03 PM, Ian Kumlien wrote: > This is a resend, try two... Please see "[PATCH v3] direct-io: fix uninitialized warning in do_direct_IO()". > --- > Hi, > > While playing around compiling the kernel i noticed the following: > fs/direct-io.c: In function ‘do_blockdev_direct_IO’: > fs/direct-io.c:1022:29: warning: ‘from’ may be used uninitialized in > this function [-Wmaybe-uninitialized] > ret = submit_page_section(dio, sdio, page, > ^ > fs/direct-io.c:913:10: note: ‘from’ was declared here > size_t from, to; > ^ > fs/direct-io.c:1011:12: warning: ‘to’ may be used uninitialized in this > function [-Wmaybe-uninitialized] > u = (to - from) >> blkbits; > ^ > fs/direct-io.c:913:16: note: ‘to’ was declared here > size_t from, to; > ^ > --- > > > And while the fix is simple, something along the lines of: > diff --git a/fs/direct-io.c b/fs/direct-io.c > index 98040ba..64a8286 100644 > --- a/fs/direct-io.c > +++ b/fs/direct-io.c > @@ -910,7 +910,7 @@ static int do_direct_IO(struct dio *dio, struct > dio_submit *sdi > > while (sdio->block_in_file < sdio->final_block_in_request) { > struct page *page; > - size_t from, to; > + size_t from, to = {0}; > page = dio_get_page(dio, sdio, &from, &to); > if (IS_ERR(page)) { > ret = PTR_ERR(page); > --- > > I however don't know if it's in the correct C standard, it compiles fine > though... (or if this is more gcc speific) > > > -- Thanks, //richard -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/