On Tue, Jul 30, 2013 at 10:13:41AM +0200, Maarten Lankhorst wrote: > The check needs to be for > 1, because ctx->acquired is already incremented. > This will prevent ww_mutex_lock_slow from returning -EDEADLK and not locking > the mutex. It caused a lot of false gpu lockups on radeon with > CONFIG_DEBUG_WW_MUTEX_SLOWPATH=y because a function that shouldn't be able > to return -EDEADLK did. > > Cc: Alex Deucher <alexander.deuc...@amd.com> > Signed-off-by: Maarten Lankhorst <maarten.lankho...@canonical.com>
Oops, thanks for catching this. Reviewed-by: Daniel Vetter <daniel.vet...@ffwll.ch> > --- > diff --git a/kernel/mutex.c b/kernel/mutex.c > index ff05f4b..a52ee7bb 100644 > --- a/kernel/mutex.c > +++ b/kernel/mutex.c > @@ -686,7 +686,7 @@ __ww_mutex_lock(struct ww_mutex *lock, struct > ww_acquire_ctx *ctx) > might_sleep(); > ret = __mutex_lock_common(&lock->base, TASK_UNINTERRUPTIBLE, > 0, &ctx->dep_map, _RET_IP_, ctx); > - if (!ret && ctx->acquired > 0) > + if (!ret && ctx->acquired > 1) > return ww_mutex_deadlock_injection(lock, ctx); > > return ret; > @@ -702,7 +702,7 @@ __ww_mutex_lock_interruptible(struct ww_mutex *lock, > struct ww_acquire_ctx *ctx) > ret = __mutex_lock_common(&lock->base, TASK_INTERRUPTIBLE, > 0, &ctx->dep_map, _RET_IP_, ctx); > > - if (!ret && ctx->acquired > 0) > + if (!ret && ctx->acquired > 1) > return ww_mutex_deadlock_injection(lock, ctx); > > return ret; > _______________________________________________ > dri-devel mailing list > dri-de...@lists.freedesktop.org > http://lists.freedesktop.org/mailman/listinfo/dri-devel -- Daniel Vetter Software Engineer, Intel Corporation +41 (0) 79 365 57 48 - http://blog.ffwll.ch -- 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/
