History log of /linux-master/include/linux/debug_locks.h
Revision Date Author Comments
# f7427ba5 25-Aug-2021 Shaokun Zhang <zhangshaokun@hisilicon.com>

locking/lockdep: Cleanup the repeated declaration

'struct task_struct' has been decleared twice, so keep the top one and
cleanup the repeated one.

Signed-off-by: Shaokun Zhang <zhangshaokun@hisilicon.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/1629875224-32751-1-git-send-email-zhangshaokun@hisilicon.com


# cbcebf5b 15-Aug-2021 Sebastian Andrzej Siewior <bigeasy@linutronix.de>

locking/lockdep: Reduce header dependencies in <linux/debug_locks.h>

The inclusion of printk.h leads to a circular dependency if spinlock_t is
based on rtmutexes on RT enabled kernels.

Include only atomic.h (xchg()) and cache.h (__read_mostly) which is all
what debug_locks.h requires.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20210815211303.484161136@linutronix.de


# 49faa777 21-Jun-2021 Peter Zijlstra <peterz@infradead.org>

locking/lockdep: Improve noinstr vs errors

Better handle the failure paths.

vmlinux.o: warning: objtool: debug_locks_off()+0x23: call to console_verbose() leaves .noinstr.text section
vmlinux.o: warning: objtool: debug_locks_off()+0x19: call to __kasan_check_write() leaves .noinstr.text section

debug_locks_off+0x19/0x40:
instrument_atomic_write at include/linux/instrumented.h:86
(inlined by) __debug_locks_off at include/linux/debug_locks.h:17
(inlined by) debug_locks_off at lib/debug_locks.c:41

Fixes: 6eebad1ad303 ("lockdep: __always_inline more for noinstr")
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20210621120120.784404944@infradead.org


# 36d818f6 11-Sep-2020 Andy Shevchenko <andriy.shevchenko@linux.intel.com>

kernel.h: Move oops_in_progress to printk.h

The oops_in_progress is defined in printk.c, so it's logical
to move oops_in_progress to printk.h.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20200911170202.8565-1-andriy.shevchenko@linux.intel.com


# 6eebad1a 03-Jun-2020 Peter Zijlstra <peterz@infradead.org>

lockdep: __always_inline more for noinstr

vmlinux.o: warning: objtool: debug_locks_off()+0xd: call to __debug_locks_off() leaves .noinstr.text section
vmlinux.o: warning: objtool: match_held_lock()+0x6a: call to look_up_lock_class.isra.0() leaves .noinstr.text section
vmlinux.o: warning: objtool: lock_is_held_type()+0x90: call to lockdep_recursion_finish() leaves .noinstr.text section

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20200603114052.185201076@infradead.org


# 01a14bda 18-Oct-2018 Waiman Long <longman@redhat.com>

locking/lockdep: Make global debug_locks* variables read-mostly

Make the frequently used lockdep global variable debug_locks read-mostly.
As debug_locks_silent is sometime used together with debug_locks,
it is also made read-mostly so that they can be close together.

With false cacheline sharing, cacheline contention problem can happen
depending on what get put into the same cacheline as debug_locks.

Signed-off-by: Waiman Long <longman@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Link: http://lkml.kernel.org/r/1539913518-15598-2-git-send-email-longman@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>


# b2441318 01-Nov-2017 Greg Kroah-Hartman <gregkh@linuxfoundation.org>

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.

By default all files without license information are under the default
license of the kernel, which is GPL version 2.

Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier. The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.

How this work was done:

Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
- file had no licensing information it it.
- file was a */uapi/* one with no licensing information in it,
- file was a */uapi/* one with existing licensing information,

Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.

The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne. Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.

The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed. Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.

Criteria used to select files for SPDX license identifier tagging was:
- Files considered eligible had to be source code files.
- Make and config files were included as candidates if they contained >5
lines of source
- File already had some variant of a license header in it (even if <5
lines).

All documentation files were explicitly excluded.

The following heuristics were used to determine which SPDX license
identifiers to apply.

- when both scanners couldn't find any license traces, file was
considered to have no license information in it, and the top level
COPYING file license applied.

For non */uapi/* files that summary was:

SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 11139

and resulted in the first patch in this series.

If that file was a */uapi/* path one, it was "GPL-2.0 WITH
Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was:

SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 WITH Linux-syscall-note 930

and resulted in the second patch in this series.

- if a file had some form of licensing information in it, and was one
of the */uapi/* ones, it was denoted with the Linux-syscall-note if
any GPL family license was found in the file or had no licensing in
it (per prior point). Results summary:

SPDX license identifier # files
---------------------------------------------------|------
GPL-2.0 WITH Linux-syscall-note 270
GPL-2.0+ WITH Linux-syscall-note 169
((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21
((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17
LGPL-2.1+ WITH Linux-syscall-note 15
GPL-1.0+ WITH Linux-syscall-note 14
((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5
LGPL-2.0+ WITH Linux-syscall-note 4
LGPL-2.1 WITH Linux-syscall-note 3
((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3
((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1

and that resulted in the third patch in this series.

- when the two scanners agreed on the detected license(s), that became
the concluded license(s).

- when there was disagreement between the two scanners (one detected a
license but the other didn't, or they both detected different
licenses) a manual inspection of the file occurred.

- In most cases a manual inspection of the information in the file
resulted in a clear resolution of the license that should apply (and
which scanner probably needed to revisit its heuristics).

- When it was not immediately clear, the license identifier was
confirmed with lawyers working with the Linux Foundation.

- If there was any question as to the appropriate license identifier,
the file was flagged for further research and to be revisited later
in time.

In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.

Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights. The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.

Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.

In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.

Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
- a full scancode scan run, collecting the matched texts, detected
license ids and scores
- reviewing anything where there was a license detected (about 500+
files) to ensure that the applied SPDX license was correct
- reviewing anything where there was no detection but the patch license
was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
SPDX license was correct

This produced a worksheet with 20 files needing minor correction. This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.

These .csv files were then reviewed by Greg. Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected. This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.) Finally Greg ran the script using the .csv files to
generate the patches.

Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>


# 1b1d2fb4 06-May-2013 Colin Cross <ccross@android.com>

lockdep: remove task argument from debug_check_no_locks_held

The only existing caller to debug_check_no_locks_held calls it
with 'current' as the task, and the freezer needs to call
debug_check_no_locks_held but doesn't already have a current
task pointer, so remove the argument. It is already assuming
that the current task is relevant by dumping the current stack
trace as part of the warning.

This was originally part of 6aa9707099c (lockdep: check that
no locks held at freeze time) which was reverted in
dbf520a9d7d4.

Original-author: Mandeep Singh Baines <msb@chromium.org>
Acked-by: Pavel Machek <pavel@ucw.cz>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Colin Cross <ccross@android.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>


# 2c2fea11 29-Apr-2013 James Hogan <jhogan@kernel.org>

debug_locks.h: make warning more verbose

The WARN_ON(1) in DEBUG_LOCKS_WARN_ON is surprisingly awkward to track
down when it's hit, as it's usually buried in macros, causing multiple
instances to land on the same line number.

This patch makes it more useful by switching to:

WARN(1, "DEBUG_LOCKS_WARN_ON(%s)", #c);

so that the particular DEBUG_LOCKS_WARN_ON is more easily identified and
grep'd for. For example:

WARNING: at kernel/mutex.c:198 _mutex_lock_nested+0x31c/0x380()
DEBUG_LOCKS_WARN_ON(l->magic != l)

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>


# dbf520a9 30-Mar-2013 Paul Walmsley <paul@pwsan.com>

Revert "lockdep: check that no locks held at freeze time"

This reverts commit 6aa9707099c4b25700940eb3d016f16c4434360d.

Commit 6aa9707099c4 ("lockdep: check that no locks held at freeze time")
causes problems with NFS root filesystems. The failures were noticed on
OMAP2 and 3 boards during kernel init:

[ BUG: swapper/0/1 still has locks held! ]
3.9.0-rc3-00344-ga937536 #1 Not tainted
-------------------------------------
1 lock held by swapper/0/1:
#0: (&type->s_umount_key#13/1){+.+.+.}, at: [<c011e84c>] sget+0x248/0x574

stack backtrace:
rpc_wait_bit_killable
__wait_on_bit
out_of_line_wait_on_bit
__rpc_execute
rpc_run_task
rpc_call_sync
nfs_proc_get_root
nfs_get_root
nfs_fs_mount_common
nfs_try_mount
nfs_fs_mount
mount_fs
vfs_kern_mount
do_mount
sys_mount
do_mount_root
mount_root
prepare_namespace
kernel_init_freeable
kernel_init

Although the rootfs mounts, the system is unstable. Here's a transcript
from a PM test:

http://www.pwsan.com/omap/testlogs/test_v3.9-rc3/20130317194234/pm/37xxevm/37xxevm_log.txt

Here's what the test log should look like:

http://www.pwsan.com/omap/testlogs/test_v3.8/20130218214403/pm/37xxevm/37xxevm_log.txt

Mailing list discussion is here:

http://lkml.org/lkml/2013/3/4/221

Deal with this for v3.9 by reverting the problem commit, until folks can
figure out the right long-term course of action.

Signed-off-by: Paul Walmsley <paul@pwsan.com>
Cc: Mandeep Singh Baines <msb@chromium.org>
Cc: Jeff Layton <jlayton@redhat.com>
Cc: Shawn Guo <shawn.guo@linaro.org>
Cc: <maciej.rutecki@gmail.com>
Cc: Fengguang Wu <fengguang.wu@intel.com>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Ben Chan <benchan@chromium.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>


# 6aa97070 27-Feb-2013 Mandeep Singh Baines <msb@chromium.org>

lockdep: check that no locks held at freeze time

We shouldn't try_to_freeze if locks are held. Holding a lock can cause a
deadlock if the lock is later acquired in the suspend or hibernate path
(e.g. by dpm). Holding a lock can also cause a deadlock in the case of
cgroup_freezer if a lock is held inside a frozen cgroup that is later
acquired by a process outside that group.

[akpm@linux-foundation.org: export debug_check_no_locks_held]
Signed-off-by: Mandeep Singh Baines <msb@chromium.org>
Cc: Ben Chan <benchan@chromium.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Ingo Molnar <mingo@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>


# 9ffc93f2 28-Mar-2012 David Howells <dhowells@redhat.com>

Remove all #inclusions of asm/system.h

Remove all #inclusions of asm/system.h preparatory to splitting and killing
it. Performed with the following command:

perl -p -i -e 's!^#\s*include\s*<asm/system[.]h>.*\n!!' `grep -Irl '^#\s*include\s*<asm/system[.]h>' *`

Signed-off-by: David Howells <dhowells@redhat.com>


# 187f1882 23-Nov-2011 Paul Gortmaker <paul.gortmaker@windriver.com>

BUG: headers with BUG/BUG_ON etc. need linux/bug.h

If a header file is making use of BUG, BUG_ON, BUILD_BUG_ON, or any
other BUG variant in a static inline (i.e. not in a #define) then
that header really should be including <linux/bug.h> and not just
expecting it to be implicitly present.

We can make this change risk-free, since if the files using these
headers didn't have exposure to linux/bug.h already, they would have
been causing compile failures/warnings.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>


# 60063497 26-Jul-2011 Arun Sharma <asharma@fb.com>

atomic: use <linux/atomic.h>

This allows us to move duplicated code in <asm/atomic.h>
(atomic_inc_not_zero() for now) to <linux/atomic.h>

Signed-off-by: Arun Sharma <asharma@fb.com>
Reviewed-by: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: David Miller <davem@davemloft.net>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Acked-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>


# f1b499f0 05-Aug-2010 John Kacur <jkacur@redhat.com>

lockdep: Remove __debug_show_held_locks

There is no longer any functional difference between
__debug_show_held_locks() and debug_show_held_locks(),
so remove the former.

Signed-off-by: John Kacur <jkacur@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1281021054-4228-1-git-send-email-jkacur@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>


# 27b19565 14-Apr-2009 Ingo Molnar <mingo@elte.hu>

lockdep: warn about lockdep disabling after kernel taint, fix

Impact: build fix for Sparc and s390

Stephen Rothwell reported that the Sparc build broke:

In file included from kernel/panic.c:12:
include/linux/debug_locks.h: In function '__debug_locks_off':
include/linux/debug_locks.h:15: error: implicit declaration of function 'xchg'

due to:

9eeba61: lockdep: warn about lockdep disabling after kernel taint

There is some inconsistency between architectures about where exactly
xchg() is defined.

The traditional place is in system.h but the more logical point for it
is in atomic.h - where most architectures (especially new ones) have
it defined. These architecture also still offer it via system.h.

Some, such as Sparc or s390 only have it in asm/system.h and not available
via asm/atomic.h at all.

Use the widest set of headers in debug_locks.h and also include asm/system.h.

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
LKML-Reference: <20090414144317.026498df.sfr@canb.auug.org.au>
Signed-off-by: Ingo Molnar <mingo@elte.hu>


# 9eeba613 10-Apr-2009 Frederic Weisbecker <fweisbec@gmail.com>

lockdep: warn about lockdep disabling after kernel taint

Impact: provide useful missing info for developers

Kernel taint can occur in several situations such as warnings,
load of prorietary or staging modules, bad page, etc...

But when such taint happens, a developer might still be working on
the kernel, expecting that lockdep is still enabled. But a taint
disables lockdep without ever warning about it.
Such a kernel behaviour doesn't really help for kernel development.

This patch adds this missing warning.

Since the taint is done most of the time after the main message that
explain the real source issue, it seems safe to warn about it inside
add_taint() so that it appears at last, without hurting the main
information.

v2: Use a generic helper to disable lockdep instead of an
open coded xchg().

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
LKML-Reference: <1239412638-6739-1-git-send-email-fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>


# 53b9d87f 11-Sep-2008 Andrew Morton <akpm@linux-foundation.org>

lock debug: sit tight when we are already in a panic

in:

> http://bugzilla.kernel.org/show_bug.cgi?id=11543

The panic code called the kexec code which called mutex_trylock() which
called spin_lock_mutex() which then stupidly went and blurted a load of
debug stuff because of in_interrupt().

Keep the lock debug code from escallating an already crappy situation.

Signed-off-by: Ingo Molnar <mingo@elte.hu>


# ca31e146 04-Jul-2008 Eduard - Gabriel Munteanu <eduard.munteanu@linux360.ro>

Move _RET_IP_ and _THIS_IP_ to include/linux/kernel.h

These two macros are useful beyond lock debugging. Moved definitions from
include/linux/debug_locks.h to include/linux/kernel.h, so code that needs
them does not have to include the former, which would have been a less
intuitive choice of a header.

Signed-off-by: Eduard - Gabriel Munteanu <eduard.munteanu@linux360.ro>
Acked-by: Pekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>


# 82a1fcb9 25-Jan-2008 Ingo Molnar <mingo@elte.hu>

softlockup: automatically detect hung TASK_UNINTERRUPTIBLE tasks

this patch extends the soft-lockup detector to automatically
detect hung TASK_UNINTERRUPTIBLE tasks. Such hung tasks are
printed the following way:

------------------>
INFO: task prctl:3042 blocked for more than 120 seconds.
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message
prctl D fd5e3793 0 3042 2997
f6050f38 00000046 00000001 fd5e3793 00000009 c06d8264 c06dae80 00000286
f6050f40 f6050f00 f7d34d90 f7d34fc8 c1e1be80 00000001 f6050000 00000000
f7e92d00 00000286 f6050f18 c0489d1a f6050f40 00006605 00000000 c0133a5b
Call Trace:
[<c04883a5>] schedule_timeout+0x6d/0x8b
[<c04883d8>] schedule_timeout_uninterruptible+0x15/0x17
[<c0133a76>] msleep+0x10/0x16
[<c0138974>] sys_prctl+0x30/0x1e2
[<c0104c52>] sysenter_past_esp+0x5f/0xa5
=======================
2 locks held by prctl/3042:
#0: (&sb->s_type->i_mutex_key#5){--..}, at: [<c0197d11>] do_fsync+0x38/0x7a
#1: (jbd_handle){--..}, at: [<c01ca3d2>] journal_start+0xc7/0xe9
<------------------

the current default timeout is 120 seconds. Such messages are printed
up to 10 times per bootup. If the system has crashed already then the
messages are not printed.

if lockdep is enabled then all held locks are printed as well.

this feature is a natural extension to the softlockup-detector (kernel
locked up without scheduling) and to the NMI watchdog (kernel locked up
with IRQs disabled).

[ Gautham R Shenoy <ego@in.ibm.com>: CPU hotplug fixes. ]
[ Andrew Morton <akpm@linux-foundation.org>: build warning fix. ]

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>


# 9127d4b1 22-Dec-2006 Ingo Molnar <mingo@elte.hu>

[PATCH] lock debugging: fix DEBUG_LOCKS_WARN_ON() & debug_locks_silent

Matthew Wilcox noticed that the debug_locks_silent use should be inverted
in DEBUG_LOCKS_WARN_ON(). This bug was causing spurious stacktraces and
incorrect failures in the locking self-test on the parisc kernel.

Bug-found-by: Matthew Wilcox <matthew@wil.cx>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>


# 2ee91f19 06-Dec-2006 Ingo Molnar <mingo@elte.hu>

[PATCH] lockdep: show more details about self-test failures

Make the locking self-test failures (of 'FAILURE' type) easier to debug by
printing more information.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>


# f86e4513 13-Aug-2006 Kyle McMartin <kyle@parisc-linux.org>

[PATCH] Need forward decl of task_struct in linux/debug_locks.h

Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>


# 9b7f750d 05-Aug-2006 Alexey Dobriyan <adobriyan@gmail.com>

[PATCH] debug_locks.h: add "struct task_struct;"

Removes many, many "declared inside parameter list" warnings on parisc.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>


# 9a11b49a 03-Jul-2006 Ingo Molnar <mingo@elte.hu>

[PATCH] lockdep: better lock debugging

Generic lock debugging:

- generalized lock debugging framework. For example, a bug in one lock
subsystem turns off debugging in all lock subsystems.

- got rid of the caller address passing (__IP__/__IP_DECL__/etc.) from
the mutex/rtmutex debugging code: it caused way too much prototype
hackery, and lockdep will give the same information anyway.

- ability to do silent tests

- check lock freeing in vfree too.

- more finegrained debugging options, to allow distributions to
turn off more expensive debugging features.

There's no separate 'held mutexes' list anymore - but there's a 'held locks'
stack within lockdep, which unifies deadlock detection across all lock
classes. (this is independent of the lockdep validation stuff - lockdep first
checks whether we are holding a lock already)

Here are the current debugging options:

CONFIG_DEBUG_MUTEXES=y
CONFIG_DEBUG_LOCK_ALLOC=y

which do:

config DEBUG_MUTEXES
bool "Mutex debugging, basic checks"

config DEBUG_LOCK_ALLOC
bool "Detect incorrect freeing of live mutexes"

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>