[PATCH] drm/xe/guc: Check CT enable state before deregistering exec queue

[Shuicheng Lin <shuicheng.lin@intel.com>]

In normal operation, a registered exec queue is disabled and
deregistered through the GuC, and freed only after the GuC confirms
completion. However, if the driver is forced to unbind while the exec
queue is still running, the user may call exec_destroy() after the GuC
has already been stopped and CT communication disabled.

In this case, the driver cannot receive a response from the GuC,
preventing proper cleanup of exec queue resources. Fix this by directly
releasing the resources when CT is disabled.

Here is the failure dmesg log:
"
[  468.089581] ---[ end trace 0000000000000000 ]---
[  468.089608] pci 0000:03:00.0: [drm] *ERROR* GT0: GUC ID manager unclean (1/65535)
[  468.090558] pci 0000:03:00.0: [drm] GT0:     total 65535
[  468.090562] pci 0000:03:00.0: [drm] GT0:     used 1
[  468.090564] pci 0000:03:00.0: [drm] GT0:     range 1..1 (1)
[  468.092716] ------------[ cut here ]------------
[  468.092719] WARNING: CPU: 14 PID: 4775 at drivers/gpu/drm/xe/xe_ttm_vram_mgr.c:298 ttm_vram_mgr_fini+0xf8/0x130 [xe]
"

Signed-off-by: Shuicheng Lin <shuicheng.lin@intel.com>
---
 drivers/gpu/drm/xe/xe_guc_submit.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/xe/xe_guc_submit.c b/drivers/gpu/drm/xe/xe_guc_submit.c
index 53024eb5670b..9d33f63d972b 100644
--- a/drivers/gpu/drm/xe/xe_guc_submit.c
+++ b/drivers/gpu/drm/xe/xe_guc_submit.c
@@ -1489,7 +1489,7 @@ static void __guc_exec_queue_process_msg_cleanup(struct xe_sched_msg *msg)
 	xe_gt_assert(guc_to_gt(guc), !(q->flags & EXEC_QUEUE_FLAG_PERMANENT));
 	trace_xe_exec_queue_cleanup_entity(q);
 
-	if (exec_queue_registered(q))
+	if (exec_queue_registered(q) && xe_guc_ct_enabled(&guc->ct))
 		disable_scheduling_deregister(guc, q);
 	else
 		__guc_exec_queue_destroy(guc, q);
-- 
2.49.0