[Intel-gfx] [PATCH] HAX: poison the CSB after use

[Chris Wilson]

---
 drivers/gpu/drm/i915/intel_lrc.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/gpu/drm/i915/intel_lrc.c b/drivers/gpu/drm/i915/intel_lrc.c
index 22b57b8926fc..4d25e25b11cc 100644
--- a/drivers/gpu/drm/i915/intel_lrc.c
+++ b/drivers/gpu/drm/i915/intel_lrc.c
@@ -910,6 +910,9 @@ static void process_csb(struct intel_engine_cs *engine)
 			  execlists->active);
 
 		status = buf[2 * head];
+		GEM_BUG_ON(!status);
+		GEM_DEBUG_EXEC(WRITE_ONCE((u32 *)(buf + 2 * head), 0));
+
 		if (status & (GEN8_CTX_STATUS_IDLE_ACTIVE |
 			      GEN8_CTX_STATUS_PREEMPTED))
 			execlists_set_active(execlists,
-- 
2.19.1