From: Corbin McElhanney <corbin.mcelhan...@amd.com>

This comment explains a previous change that adds some complexity
to the context free in dc:

commit 9ad58779a895 ("drm/amd/display: Fix accessing freed memory")

Signed-off-by: Corbin McElhanney <corbin.mcelhan...@amd.com>
Reviewed-by: Tony Cheng <tony.ch...@amd.com>
Acked-by: Harry Wentland <harry.wentl...@amd.com>
---
 drivers/gpu/drm/amd/display/dc/core/dc.c | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/drivers/gpu/drm/amd/display/dc/core/dc.c 
b/drivers/gpu/drm/amd/display/dc/core/dc.c
index 477024c467e6..33c3d88b1c86 100644
--- a/drivers/gpu/drm/amd/display/dc/core/dc.c
+++ b/drivers/gpu/drm/amd/display/dc/core/dc.c
@@ -1740,6 +1740,15 @@ void dc_update_planes_and_stream(struct dc *dc,
        }
 
        if (core_dc->current_context != context) {
+
+               /* Since memory free requires elevated IRQL, an interrupt
+                * request is generated by mem free. If this happens
+                * between freeing and reassigning the context, our vsync
+                * interrupt will call into dc and cause a memory
+                * corruption BSOD. Hence, we first reassign the context,
+                * then free the old context.
+                */
+
                struct validate_context *old = core_dc->current_context;
 
                core_dc->current_context = context;
-- 
2.11.0

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