According the ww-mutex-design.txt documentation, the ww_mutex_lock_interruptible and ww_mutex_lock functions should return -EDEADLK when faced with a deadlock. To do so, the detect_deadlock flag in the rt_mutex_slowlock calls should be enabled. This patch corrects potential deadlocks when running PREEMPT_RT with nouveau driver.
PS: Sorry to post again, CC'ing -rt maintainers now. Signed-off-by: Gustavo Bittencourt <gbit...@gmail.com> --- kernel/locking/rtmutex.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/kernel/locking/rtmutex.c b/kernel/locking/rtmutex.c index 6c40660..3f6ef91 100644 --- a/kernel/locking/rtmutex.c +++ b/kernel/locking/rtmutex.c @@ -1965,7 +1965,7 @@ __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_); - ret = rt_mutex_slowlock(&lock->base.lock, TASK_INTERRUPTIBLE, NULL, 0, ww_ctx); + ret = rt_mutex_slowlock(&lock->base.lock, TASK_INTERRUPTIBLE, NULL, 1, ww_ctx); if (ret) mutex_release(&lock->base.dep_map, 1, _RET_IP_); else if (!ret && ww_ctx->acquired > 1) @@ -1984,7 +1984,7 @@ __ww_mutex_lock(struct ww_mutex *lock, struct ww_acquire_ctx *ww_ctx) 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); + ret = rt_mutex_slowlock(&lock->base.lock, TASK_UNINTERRUPTIBLE, NULL, 1, ww_ctx); if (ret) mutex_release(&lock->base.dep_map, 1, _RET_IP_); else if (!ret && ww_ctx->acquired > 1) -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/