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 | 5 +++--
drivers/gpu/drm/amd/display/dc/core/dc_surface.c | 5 +++--
2 files changed, 6 insertions(+), 4 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 7666cdc78f4e..a5a304a3f802 100644
--- a/drivers/gpu/drm/amd/display/dc/core/dc_stream.c
+++ b/drivers/gpu/drm/amd/display/dc/core/dc_stream.c
@@ -233,8 +233,9 @@ struct dc_stream_state *dc_create_stream_for_sink(
fail:
if (stream) {
- kfree(stream->update_scratch);
- kfree(stream);
+ if (stream->update_scratch)
+
DC_RUN_WITH_PREEMPTION_ENABLED(kfree(stream->update_scratch));
+ 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 72845fc788f3..04982673ffbc 100644
--- a/drivers/gpu/drm/amd/display/dc/core/dc_surface.c
+++ b/drivers/gpu/drm/amd/display/dc/core/dc_surface.c
@@ -33,6 +33,7 @@
#include "dpp.h"
#include "dc_plane_priv.h"
+#include "dc_fpu.h"
/*******************************************************************************
* Private functions
@@ -86,8 +87,8 @@ 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;
--
2.55.0
Fix for stable with the old error handling in
dc_create_stream_for_sink() and compile fix form arm64/clang.
Bert Karwatzki
