Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754926Ab0KPRAS (ORCPT ); Tue, 16 Nov 2010 12:00:18 -0500 Received: from bear.ext.ti.com ([192.94.94.41]:44023 "EHLO bear.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752552Ab0KPRAR convert rfc822-to-8bit (ORCPT ); Tue, 16 Nov 2010 12:00:17 -0500 From: "Aguirre, Sergio" To: Darren Hart CC: LKML , Thomas Gleixner , Peter Zijlstra , Ingo Molnar , Namhyung Kim Date: Tue, 16 Nov 2010 10:59:53 -0600 Subject: RE: [RFC][PATCH] futex: Hide false positive about uninit var usage Thread-Topic: [RFC][PATCH] futex: Hide false positive about uninit var usage Thread-Index: AcuFrWPoMi0rPGKtSGee271h6+oKWAAAfu0A Message-ID: References: <1289925157-17054-1-git-send-email-saaguirre@ti.com> <4CE2B4AC.5080606@linux.intel.com> In-Reply-To: <4CE2B4AC.5080606@linux.intel.com> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: acceptlanguage: en-US Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 8BIT MIME-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2310 Lines: 73 Hi Darren, > -----Original Message----- > From: Darren Hart [mailto:dvhart@linux.intel.com] > Sent: Tuesday, November 16, 2010 10:43 AM > To: Aguirre, Sergio > Cc: LKML; Thomas Gleixner; Peter Zijlstra; Ingo Molnar; Namhyung Kim > Subject: Re: [RFC][PATCH] futex: Hide false positive about uninit var > usage > > On 11/16/2010 08:32 AM, Sergio Aguirre wrote: > > In exit_robust_list, there was this warning shown: > > > > kernel/futex.c: In function 'exit_robust_list': > > kernel/futex.c:2492: warning: 'next_pi' may be used uninitialized in > this function > > > > Which is a false positive, since in the function, the only scenario > > possible in which the var is read, is after a successful excecution of > > fetch_robust_entry, which populates the variable. > > > > So there's no real possibility of it being used uninitialized. > > Hi Sergio, > > You are correct. Thomas has recently pulled my fix for this into tip, it > should be queued for mainline already. Oh ok. Sorry, I didn't know that. Please ignore this patch then. Regards, Sergio > > Thanks, > > Darren Hart > > > > > Signed-off-by: Sergio Aguirre > > Cc: Thomas Gleixner > > Cc: Peter Zijlstra > > Cc: Darren Hart > > Cc: Ingo Molnar > > Cc: Namhyung Kim > > --- > > kernel/futex.c | 3 ++- > > 1 files changed, 2 insertions(+), 1 deletions(-) > > > > diff --git a/kernel/futex.c b/kernel/futex.c > > index 6c683b3..3646157 100644 > > --- a/kernel/futex.c > > +++ b/kernel/futex.c > > @@ -2489,7 +2489,8 @@ void exit_robust_list(struct task_struct *curr) > > { > > struct robust_list_head __user *head = curr->robust_list; > > struct robust_list __user *entry, *next_entry, *pending; > > - unsigned int limit = ROBUST_LIST_LIMIT, pi, next_pi, pip; > > + unsigned int limit = ROBUST_LIST_LIMIT, pi; > > + unsigned int uninitialized_var(next_pi), pip; > > unsigned long futex_offset; > > int rc; > > > > > -- > Darren Hart > Yocto Linux Kernel -- 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/