From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail143.messagelabs.com (mail143.messagelabs.com [216.82.254.35]) by kanga.kvack.org (Postfix) with ESMTP id 7BAEA900138 for ; Thu, 4 Aug 2011 12:05:24 -0400 (EDT) Received: by eyh6 with SMTP id 6so1426056eyh.20 for ; Thu, 04 Aug 2011 09:05:21 -0700 (PDT) Date: Thu, 4 Aug 2011 19:04:16 +0300 From: Sergey Senozhatsky Subject: Re: select_task_rq_fair: WARNING: at kernel/lockdep.c match_held_lock Message-ID: <20110804160415.GC3562@swordfish.minsk.epam.com> References: <20110804141306.GA3536@swordfish.minsk.epam.com> <1312470358.16729.25.camel@twins> <20110804153752.GA3562@swordfish.minsk.epam.com> <1312472867.16729.38.camel@twins> <20110804155347.GB3562@swordfish.minsk.epam.com> <1312473473.16729.44.camel@twins> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1312473473.16729.44.camel@twins> Sender: owner-linux-mm@kvack.org List-ID: To: Peter Zijlstra Cc: Ingo Molnar , Thomas Gleixner , Andrew Morton , linux-kernel@vger.kernel.org, KAMEZAWA Hiroyuki , linux-mm@kvack.org On (08/04/11 17:57), Peter Zijlstra wrote: > > > > > > [ 132.794685] WARNING: at kernel/lockdep.c:3117 match_held_lock+0xf6/0x12e() > > > > > > Just to double check, that line is: > > > > > > if (DEBUG_LOCKS_WARN_ON(!hlock->nest_lock)) > > > > > > in your kernel source? > > > > > > > Nope, that's `if (DEBUG_LOCKS_WARN_ON(!class))' > > > > 3106 static int match_held_lock(struct held_lock *hlock, struct lockdep_map *lock) > > 3107 { > > 3108 if (hlock->instance == lock) > > 3109 return 1; > > 3110 > > 3111 if (hlock->references) { > > 3112 struct lock_class *class = lock->class_cache[0]; > > 3113 > > 3114 if (!class) > > 3115 class = look_up_lock_class(lock, 0); > > 3116 > > 3117 if (DEBUG_LOCKS_WARN_ON(!class)) > > 3118 return 0; > > 3119 > > 3120 if (DEBUG_LOCKS_WARN_ON(!hlock->nest_lock)) > > 3121 return 0; > > 3122 > > 3123 if (hlock->class_idx == class - lock_classes + 1) > > 3124 return 1; > > 3125 } > > 3126 > > 3127 return 0; > > 3128 } > > 3129 > > Ah, in that case my previous analysis was pointless and I shall need to > scratch my head some more. > That was a good idea to check what's going on on 3117 line. Well, your analysis was correct, it's just we have different match_held_lock() lines, and I guess we may have different lines within match_held_lock()-callers in that case. Just for note, I'm using the latest git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6.git $ git pull Already up-to-date. Sergey -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: email@kvack.org