[PATCH] drm/i915: Use tasklet_unlock_spin_wait() in __tasklet_disable_sync_once()

From: Sebastian Andrzej Siewior
Date: Tue Mar 23 2021 - 05:23:12 EST

The i915 driver has its own tasklet interface which was overseen in the
tasklet rework. __tasklet_disable_sync_once() is a wrapper around
tasklet_unlock_wait(). tasklet_unlock_wait() might sleep, but the i915
wrappers invoke it from non-preemtible contexts with bottom halves disabled.

Use tasklet_unlock_spin_wait() instead which can be invoked from
non-preemptible contexts.

Fixes: da044747401fc ("tasklets: Replace spin wait in tasklet_unlock_wait()")
Reported-by: kernel test robot <oliver.sang@xxxxxxxxx>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx>
drivers/gpu/drm/i915/i915_gem.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/i915/i915_gem.h b/drivers/gpu/drm/i915/i915_gem.h
index e622aee6e4be9..440c35f1abc9e 100644
--- a/drivers/gpu/drm/i915/i915_gem.h
+++ b/drivers/gpu/drm/i915/i915_gem.h
@@ -105,7 +105,7 @@ static inline bool tasklet_is_locked(const struct tasklet_struct *t)
static inline void __tasklet_disable_sync_once(struct tasklet_struct *t)
if (!atomic_fetch_inc(&t->count))
- tasklet_unlock_wait(t);
+ tasklet_unlock_spin_wait(t);

static inline bool __tasklet_is_enabled(const struct tasklet_struct *t)