From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <linux-kernel-owner@vger.kernel.org>
Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand
	id S1753151AbbFCGnQ (ORCPT <rfc822;w@1wt.eu>);
	Wed, 3 Jun 2015 02:43:16 -0400
Received: from mail-pa0-f47.google.com ([209.85.220.47]:35025 "EHLO
	mail-pa0-f47.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org
	with ESMTP id S1752539AbbFCGnH (ORCPT
	<rfc822;linux-kernel@vger.kernel.org>);
	Wed, 3 Jun 2015 02:43:07 -0400
Date: Wed, 3 Jun 2015 12:12:59 +0530
From: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
To: Tolga Ceylan <tolga.ceylan@gmail.com>
Cc: Oleg Drokin <oleg.drokin@intel.com>,
        Andreas Dilger <andreas.dilger@intel.com>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Julia Lawall <Julia.Lawall@lip6.fr>, Greg Donald <gdonald@gmail.com>,
        Joe Perches <joe@perches.com>,
        Darshana Padmadas <darshanapadmadas@gmail.com>,
        Arjun AK <arjunak234@gmail.com>, HPDD-discuss@ml01.01.org,
        devel@driverdev.osuosl.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 1/1] staging: lustre/lustre/obdclass/llog_cat.c: get rid
 of sparse context imbalance warning
Message-ID: <20150603064259.GE4936@sudip-PC>
References: <1433275040-23345-1-git-send-email-tolga.ceylan@gmail.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <1433275040-23345-1-git-send-email-tolga.ceylan@gmail.com>
User-Agent: Mutt/1.5.21 (2010-09-15)
Sender: linux-kernel-owner@vger.kernel.org
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

On Tue, Jun 02, 2015 at 12:57:20PM -0700, Tolga Ceylan wrote:
> In llog_cat_new_log(), sparse emits a context imbalance (unexpected lock)
> warning due its inability to detect the noreturn attribute in
> lbug_with_lock() function inside LBUG macro. Adding a never reached
> return statement suppresses this warning.
but adding a statement which never executes, is that the correct solution?
what about :

diff --git a/drivers/staging/lustre/lustre/obdclass/llog_cat.c b/drivers/staging/lustre/lustre/obdclass/llog_cat.c
index c8f6ab0..1cb3495 100644
--- a/drivers/staging/lustre/lustre/obdclass/llog_cat.c
+++ b/drivers/staging/lustre/lustre/obdclass/llog_cat.c
@@ -103,13 +103,12 @@ static int llog_cat_new_log(const struct lu_env *env,
 
 	spin_lock(&loghandle->lgh_hdr_lock);
 	llh->llh_count++;
-	if (ext2_set_bit(index, llh->llh_bitmap)) {
-		CERROR("argh, index %u already set in log bitmap?\n",
-		       index);
-		spin_unlock(&loghandle->lgh_hdr_lock);
+	rc = ext2_set_bit(index, llh->llh_bitmap);
+	spin_unlock(&loghandle->lgh_hdr_lock);
+	if (rc) {
+		CERROR("argh, index %u already set in log bitmap?\n", index);
 		LBUG(); /* should never happen */
 	}
-	spin_unlock(&loghandle->lgh_hdr_lock);
 
 	cathandle->lgh_last_idx = index;
 	llh->llh_tail.lrt_index = index;


regards
sudip