public inbox for linux-kernel@vger.kernel.org
 help / color / mirror / Atom feed
From: Greg KH <gregkh@suse.de>
To: linux-kernel@vger.kernel.org, stable@kernel.org,
	Justin Forbes <jmforbes@linuxtx.org>,
	Zwane Mwaikambo <zwane@arm.linux.org.uk>,
	"Theodore Ts'o" <tytso@mit.edu>,
	Randy Dunlap <rdunlap@xenotime.net>,
	Dave Jones <davej@redhat.com>,
	Chuck Wolber <chuckw@quantumlinux.com>,
	Chris Wedgwood <reviews@ml.cw.f00f.org>,
	Michael Krufky <mkrufky@linuxtv.org>,
	Chuck Ebbert <cebbert@redhat.com>,
	Domenico Andreoli <cavokz@gmail.com>,
	torvalds@linux-foundation.org, akpm@linux-foundation.org,
	alan@lxorguk.ukuu.org.uk
Subject: [patch 27/26] lockdep: fix mismatched lockdep_depth/curr_chain_hash
Date: Wed, 31 Oct 2007 09:25:14 -0700	[thread overview]
Message-ID: <20071031162514.GB22117@kroah.com> (raw)
In-Reply-To: <20071031151015.GA2437@kroah.com>

[one more patch added to the 2.6.22-stable queue]


From: Gregory Haskins <ghaskins@novell.com>

patch 3aa416b07f0adf01c090baab26fb70c35ec17623 in mainline.

lockdep: fix mismatched lockdep_depth/curr_chain_hash

It is possible for the current->curr_chain_key to become inconsistent with the
current index if the chain fails to validate.  The end result is that future
lock_acquire() operations may inadvertently fail to find a hit in the cache
resulting in a new node being added to the graph for every acquire.

[ peterz: this might explain some of the lockdep is so _slow_ complaints. ]
[ mingo: this does not impact the correctness of validation, but may slow
  down future operations significantly, if the chain gets very long. ]

Signed-off-by: Gregory Haskins <ghaskins@novell.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

--- a/kernel/lockdep.c
+++ b/kernel/lockdep.c
@@ -2166,7 +2166,6 @@ out_calc_hash:
 	}
 #endif
 	chain_key = iterate_chain_key(chain_key, id);
-	curr->curr_chain_key = chain_key;
 
 	/*
 	 * Trylock needs to maintain the stack of held locks, but it
@@ -2215,6 +2214,7 @@ out_calc_hash:
 		if (unlikely(!debug_locks))
 			return 0;
 
+	curr->curr_chain_key = chain_key;
 	curr->lockdep_depth++;
 	check_chain_key(curr);
 #ifdef CONFIG_DEBUG_LOCKDEP

_______________________________________________
stable mailing list
stable@linux.kernel.org
http://linux.kernel.org/mailman/listinfo/stable


      parent reply	other threads:[~2007-10-31 16:29 UTC|newest]

Thread overview: 29+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <20071031150535.967437651@mini.kroah.org>
2007-10-31 15:10 ` [patch 00/26] 2.6.22-stable review Greg KH
2007-10-31 15:10   ` [patch 01/26] ACPI: disable lower idle C-states across suspend/resume Greg KH
2007-10-31 15:10   ` [patch 02/26] Fix ESP host instance numbering Greg KH
2007-10-31 15:11   ` [patch 03/26] Fix cls_u32 error return handling Greg KH
2007-10-31 15:11   ` [patch 04/26] Fix ieee80211 handling of bogus hdrlength field Greg KH
2007-10-31 15:11   ` [patch 05/26] Fix some cases of missed IPV6 DAD Greg KH
2007-10-31 15:11   ` [patch 06/26] Fix ipv6 redirect processing, leads to TAHI failures Greg KH
2007-10-31 15:11   ` [patch 07/26] Fix ROSE module unload oops Greg KH
2007-10-31 15:11   ` [patch 08/26] Fix zero length socket write() semantics Greg KH
2007-10-31 15:11   ` [patch 09/26] Fix sys_ipc() SEMCTL on sparc64 Greg KH
2007-10-31 15:11   ` [patch 10/26] Fix TCPs ->fastpath_cnt_hit handling Greg KH
2007-10-31 15:11   ` [patch 11/26] : Fix TCP MD5 on big-endian Greg KH
2007-10-31 15:11   ` [patch 12/26] : Fix TCP initial sequence number selection Greg KH
2007-10-31 15:11   ` [patch 13/26] mac80211: filter locally-originated multicast frames Greg KH
2007-10-31 15:11   ` [patch 14/26] libertas: fix endianness breakage Greg KH
2007-10-31 15:11   ` [patch 15/26] libertas: more " Greg KH
2007-10-31 15:11   ` [patch 16/26] Add get_unaligned to ieee80211_get_radiotap_len Greg KH
2007-10-31 15:11   ` [patch 17/26] firewire: fix unloading of fw-ohci while devices are attached Greg KH
2007-10-31 15:12   ` [patch 18/26] netdrvr: natsemi: Fix device removal bug Greg KH
2007-10-31 15:12   ` [patch 19/26] dm9601: Fix receive MTU Greg KH
2007-10-31 15:12   ` [patch 20/26] V4L: ivtv: fix udma yuv bug Greg KH
2007-10-31 15:12   ` [patch 21/26] hwmon/lm87: Fix a division by zero Greg KH
2007-10-31 15:12   ` [patch 22/26] hwmon/lm87: Disable VID when it should be Greg KH
2007-10-31 15:12   ` [patch 23/26] hwmon/w83627hf: Fix setting fan min right after driver load Greg KH
2007-10-31 15:12   ` [patch 24/26] hwmon/w83627hf: Dont assume bank 0 Greg KH
2007-10-31 15:12   ` [patch 25/26] i915: fix vbl swap allocation size Greg KH
2007-10-31 15:12   ` [patch 26/26] POWERPC: Fix handling of stfiwx math emulation Greg KH
2007-10-31 15:21   ` [patch 00/26] 2.6.22-stable review Greg KH
2007-10-31 16:25   ` Greg KH [this message]

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20071031162514.GB22117@kroah.com \
    --to=gregkh@suse.de \
    --cc=akpm@linux-foundation.org \
    --cc=alan@lxorguk.ukuu.org.uk \
    --cc=cavokz@gmail.com \
    --cc=cebbert@redhat.com \
    --cc=chuckw@quantumlinux.com \
    --cc=davej@redhat.com \
    --cc=jmforbes@linuxtx.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mkrufky@linuxtv.org \
    --cc=rdunlap@xenotime.net \
    --cc=reviews@ml.cw.f00f.org \
    --cc=stable@kernel.org \
    --cc=torvalds@linux-foundation.org \
    --cc=tytso@mit.edu \
    --cc=zwane@arm.linux.org.uk \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox