After the context is unpinned the backing memory can also be unpinned,
so any accesses via the lrc_reg_state pointer can end up in unmapped
memory. To avoid that, make sure to only access that memory if the
context is pinned when printing its info.
Fixes: 28ff6520a34d ("drm/i915/guc: Update GuC debugfs to support new GuC")
Signed-off-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@xxxxxxxxx>
Cc: John Harrison <John.C.Harrison@xxxxxxxxx>
Cc: Matthew Brost <matthew.brost@xxxxxxxxx>
---
I believe this should fix issue #13343, but I wasn't able to repro
the bug to confirm that it is indeed gone with this change.
.../gpu/drm/i915/gt/uc/intel_guc_submission.c | 20 +++++++++++++------
1 file changed, 14 insertions(+), 6 deletions(-)
diff --git a/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c b/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c
index 12f1ba7ca9c1..22a73e2e6340 100644
--- a/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c
+++ b/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c
@@ -5519,12 +5519,20 @@ static inline void guc_log_context(struct drm_printer *p,
{
drm_printf(p, "GuC lrc descriptor %u:\n", ce->guc_id.id);
drm_printf(p, "\tHW Context Desc: 0x%08x\n", ce->lrc.lrca);
- drm_printf(p, "\t\tLRC Head: Internal %u, Memory %u\n",
- ce->ring->head,
- ce->lrc_reg_state[CTX_RING_HEAD]);
- drm_printf(p, "\t\tLRC Tail: Internal %u, Memory %u\n",
- ce->ring->tail,
- ce->lrc_reg_state[CTX_RING_TAIL]);
+ if (intel_context_pin_if_active(ce)) {
+ drm_printf(p, "\t\tLRC Head: Internal %u, Memory %u\n",
+ ce->ring->head,
+ ce->lrc_reg_state[CTX_RING_HEAD]);
+ drm_printf(p, "\t\tLRC Tail: Internal %u, Memory %u\n",
+ ce->ring->tail,
+ ce->lrc_reg_state[CTX_RING_TAIL]);
+ intel_context_unpin(ce);
+ } else {
+ drm_printf(p, "\t\tLRC Head: Internal %u, Memory not pinned\n",
+ ce->ring->head);
+ drm_printf(p, "\t\tLRC Tail: Internal %u, Memory not pinned\n",
+ ce->ring->tail);
+ }
drm_printf(p, "\t\tContext Pin Count: %u\n",
atomic_read(&ce->pin_count));
drm_printf(p, "\t\tGuC ID Ref Count: %u\n",
--
2.43.0
