diff options
| author | Mike Galbraith <umgwanakikbuti@gmail.com> | 2014-06-02 15:12:44 +0200 |
|---|---|---|
| committer | Anders Roxell <anders.roxell@linaro.org> | 2015-03-23 09:31:14 +0100 |
| commit | 983e44f540f4710d772c66a59e6e58922231f236 (patch) | |
| tree | 77973b2b193a75332ac6b2457f63ba4c47d5b248 | |
| parent | ec433fa41ae2effb365d43b2c07aabb596a5d1bd (diff) | |
rt,locking: fix __ww_mutex_lock_interruptible() lockdep annotation
Using mutex_acquire_nest() as used in __ww_mutex_lock() fixes the
splat below. Remove superfluous line break in __ww_mutex_lock()
as well.
|=============================================
|[ INFO: possible recursive locking detected ]
|3.14.4-rt5 #26 Not tainted
|---------------------------------------------
|Xorg/4298 is trying to acquire lock:
| (reservation_ww_class_mutex){+.+.+.}, at: [<ffffffffa02b4270>] nouveau_gem_ioctl_pushbuf+0x870/0x19f0 [nouveau]
|but task is already holding lock:
| (reservation_ww_class_mutex){+.+.+.}, at: [<ffffffffa02b4270>] nouveau_gem_ioctl_pushbuf+0x870/0x19f0 [nouveau]
|other info that might help us debug this:
| Possible unsafe locking scenario:
| CPU0
| ----
| lock(reservation_ww_class_mutex);
| lock(reservation_ww_class_mutex);
|
| *** DEADLOCK ***
|
| May be due to missing lock nesting notation
|
|3 locks held by Xorg/4298:
| #0: (&cli->mutex){+.+.+.}, at: [<ffffffffa02b597b>] nouveau_abi16_get+0x2b/0x100 [nouveau]
| #1: (reservation_ww_class_acquire){+.+...}, at: [<ffffffffa0160cd2>] drm_ioctl+0x4d2/0x610 [drm]
| #2: (reservation_ww_class_mutex){+.+.+.}, at: [<ffffffffa02b4270>] nouveau_gem_ioctl_pushbuf+0x870/0x19f0 [nouveau]
Cc: stable-rt@vger.kernel.org
Signed-off-by: Mike Galbraith <umgwanakikbuti@gmail.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Anders Roxell <anders.roxell@linaro.org>
| -rw-r--r-- | kernel/locking/rtmutex.c | 5 |
1 files changed, 2 insertions, 3 deletions
diff --git a/kernel/locking/rtmutex.c b/kernel/locking/rtmutex.c index 74a824523d3a..1794fae96a2a 100644 --- a/kernel/locking/rtmutex.c +++ b/kernel/locking/rtmutex.c @@ -2238,7 +2238,7 @@ __ww_mutex_lock_interruptible(struct ww_mutex *lock, struct ww_acquire_ctx *ww_c might_sleep(); - mutex_acquire(&lock->base.dep_map, 0, 0, _RET_IP_); + mutex_acquire_nest(&lock->base.dep_map, 0, 0, &ww_ctx->dep_map, _RET_IP_); ret = rt_mutex_slowlock(&lock->base.lock, TASK_INTERRUPTIBLE, NULL, 0, ww_ctx); if (ret) mutex_release(&lock->base.dep_map, 1, _RET_IP_); @@ -2256,8 +2256,7 @@ __ww_mutex_lock(struct ww_mutex *lock, struct ww_acquire_ctx *ww_ctx) might_sleep(); - mutex_acquire_nest(&lock->base.dep_map, 0, 0, &ww_ctx->dep_map, - _RET_IP_); + mutex_acquire_nest(&lock->base.dep_map, 0, 0, &ww_ctx->dep_map, _RET_IP_); ret = rt_mutex_slowlock(&lock->base.lock, TASK_UNINTERRUPTIBLE, NULL, 0, ww_ctx); if (ret) mutex_release(&lock->base.dep_map, 1, _RET_IP_); |