Waiman Long 4a195a0bc2 locking/lockdep: Add debug_locks check in __lock_downgrade() ...

commit 7149258057 upstream.

Tetsuo Handa had reported he saw an incorrect "downgrading a read lock"
warning right after a previous lockdep warning. It is likely that the
previous warning turned off lock debugging causing the lockdep to have
inconsistency states leading to the lock downgrade warning.

Fix that by add a check for debug_locks at the beginning of
__lock_downgrade().

Debugged-by: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Reported-by: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Reported-by: syzbot+53383ae265fb161ef488@syzkaller.appspotmail.com
Signed-off-by: Waiman Long <longman@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
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: https://lkml.kernel.org/r/1547093005-26085-1-git-send-email-longman@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

2019-03-27 14:13:54 +09:00

..

lockdep_internals.h

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

2017-11-02 11:10:55 +01:00

lockdep_proc.c

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

2017-11-02 11:10:55 +01:00

lockdep_states.h

…

lockdep.c

locking/lockdep: Add debug_locks check in __lock_downgrade()

2019-03-27 14:13:54 +09:00

locktorture.c

locking/locktorture: Fix num reader/writer corner cases

2018-03-19 08:42:56 +01:00

Makefile

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

2017-11-02 11:10:55 +01:00

mcs_spinlock.h

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

2017-11-02 11:10:55 +01:00

mutex-debug.c

…

mutex-debug.h

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

2017-11-02 11:10:55 +01:00

mutex.c

…

mutex.h

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

2017-11-02 11:10:55 +01:00

osq_lock.c

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

2017-11-02 11:10:55 +01:00

percpu-rwsem.c

…

qrwlock.c

…

qspinlock_paravirt.h

locking/qspinlock: Remove duplicate clear_pending() function from PV code

2018-12-21 14:13:09 +01:00

qspinlock_stat.h

…

qspinlock.c

locking/qspinlock, x86: Provide liveness guarantee

2018-12-21 14:13:09 +01:00

rtmutex_common.h

futex: Avoid violating the 10th rule of futex

2018-01-23 19:58:11 +01:00

rtmutex-debug.c

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

2017-11-02 11:10:55 +01:00

rtmutex-debug.h

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

2017-11-02 11:10:55 +01:00

rtmutex.c

futex: Handle early deadlock return correctly

2019-02-12 19:46:12 +01:00

rtmutex.h

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

2017-11-02 11:10:55 +01:00

rwsem-spinlock.c

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

2017-11-02 11:10:55 +01:00

rwsem-xadd.c

locking/rwsem: Fix (possible) missed wakeup

2019-03-05 17:58:00 +01:00

rwsem.c

locking/rwsem: Add a new RWSEM_ANONYMOUSLY_OWNED flag

2018-06-21 04:03:00 +09:00

rwsem.h

locking/rwsem: Add a new RWSEM_ANONYMOUSLY_OWNED flag

2018-06-21 04:03:00 +09:00

semaphore.c

…

spinlock_debug.c

…

spinlock.c

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

2017-11-02 11:10:55 +01:00

test-ww_mutex.c

locking/ww_mutex: Fix runtime warning in the WW mutex selftest

2018-11-04 14:52:41 +01:00