On PREEMPT_RT kernels kvzalloc_obj() can sleep because spin_lock is
converted to rt_mutex. dc_create_plane_state() can be called while
inside an FPU-guarded region, resuling in "scheduling while atomic"
errors on PREEMPT_RT kernels.
Fix this by calling kvzalloc_obj() with DC_RUN_WITH_PREEMPTION_ENABLED().
Also fix the error path in dc_create_stream_for_sink().
Fixes: 3539437f354b ("drm/amd/display: Move FPU Guards From DML To DC - Part 1")
Link: https://lore.kernel.org/lkml/[email protected]/
Signed-off-by: Bert Karwatzki <[email protected]>
---
drivers/gpu/drm/amd/display/dc/core/dc_stream.c | 2 +-
drivers/gpu/drm/amd/display/dc/core/dc_surface.c | 4 ++--
2 files changed, 3 insertions(+), 3 deletions(-)
diff --git a/drivers/gpu/drm/amd/display/dc/core/dc_stream.c
b/drivers/gpu/drm/amd/display/dc/core/dc_stream.c
index cdcf140bc1bb..accad9e20e88 100644
--- a/drivers/gpu/drm/amd/display/dc/core/dc_stream.c
+++ b/drivers/gpu/drm/amd/display/dc/core/dc_stream.c
@@ -229,7 +229,7 @@ struct dc_stream_state *dc_create_stream_for_sink(
fail:
if (stream)
- kfree(stream);
+ DC_RUN_WITH_PREEMPTION_ENABLED(kfree(stream));
return NULL;
}
diff --git a/drivers/gpu/drm/amd/display/dc/core/dc_surface.c
b/drivers/gpu/drm/amd/display/dc/core/dc_surface.c
index 88e825a6582c..d5c6427796b6 100644
--- a/drivers/gpu/drm/amd/display/dc/core/dc_surface.c
+++ b/drivers/gpu/drm/amd/display/dc/core/dc_surface.c
@@ -85,8 +85,8 @@ uint8_t dc_plane_get_pipe_mask(struct dc_state *dc_state,
const struct dc_plane
******************************************************************************/
struct dc_plane_state *dc_create_plane_state(const struct dc *dc)
{
- struct dc_plane_state *plane_state = kvzalloc_obj(*plane_state,
- GFP_ATOMIC);
+ struct dc_plane_state *plane_state;
+ DC_RUN_WITH_PREEMPTION_ENABLED(plane_state = kvzalloc_obj(*plane_state,
GFP_ATOMIC));
if (NULL == plane_state)
return NULL;
--
2.53.0
Rebased to next-20260729+. In these version the allocation of
update_scratch has been removed from dc_create_stream_for_sink().
Bert Karwatzki
