[Intel-gfx] [CI 2/2] drm/i915: Assert that the context-switch completion matches our context

[Chris Wilson]

When execlists signals the context completion, it also provides the
context id for the status event. Assert that id matches the one we expect.

v2: The upper dword of the context status is a duplicate of the upper
dword from elsp submission (i.e. includes the group id as well as the
context id). Include this check as well.
v3: Only check against lrc_desc (as this contains the hw_id check)

Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
Cc: Joonas Lahtinen <joonas.lahtinen at linux.intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin at intel.com>
Cc: Mika Kuoppala <mika.kuoppala at intel.com>
Reviewed-by: Mika Kuoppala <mika.kuoppala at intel.com>
---
 drivers/gpu/drm/i915/intel_lrc.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/gpu/drm/i915/intel_lrc.c b/drivers/gpu/drm/i915/intel_lrc.c
index 432ee495dec2..eceffe25c022 100644
--- a/drivers/gpu/drm/i915/intel_lrc.c
+++ b/drivers/gpu/drm/i915/intel_lrc.c
@@ -595,6 +595,11 @@ static void intel_lrc_irq_handler(unsigned long data)
 			if (!(status & GEN8_CTX_STATUS_COMPLETED_MASK))
 				continue;
 
+			/* Check the context/desc id for this event matches */
+			GEM_BUG_ON(readl(buf + 2 * idx + 1) !=
+				   upper_32_bits(intel_lr_context_descriptor(port[0].request->ctx,
+									     engine)));
+
 			GEM_BUG_ON(port[0].count == 0);
 			if (--port[0].count == 0) {
 				GEM_BUG_ON(status & GEN8_CTX_STATUS_PREEMPTED);
-- 
2.11.0