Tests that are causing pagefaults should wait for exec to queue
ban/finish otherwise pending engine resets because of on-going
pagefaults would cause failure in subsequent tests to fail.

Not all execs will generate page faults and in such case reading ban
property is not enough but the signal should either -EIO or 0.
so read that instead.

v2: specify timeout reason and iterate over exec_queues(Andrzej)
v3: increase timeout
v4: check for signal status to be -EIO/0.

Cc: Andrzej Hajda <andrzej.hajda@intel.com>
Cc: Kamil Konieczny <kamil.konieczny@linux.intel.com>
Cc: Matthew Brost <matthew.brost@intel.com>
Cc: Tejas Upadhyay <tejas.upadhyay@intel.com>
Link: https://gitlab.freedesktop.org/drm/xe/kernel/-/issues/1630
Signed-off-by: Nirmoy Das <nirmoy.das@intel.com>
---
 tests/intel/xe_exec_fault_mode.c | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/tests/intel/xe_exec_fault_mode.c b/tests/intel/xe_exec_fault_mode.c
index 1f1f1e50b..fa050d0dc 100644
--- a/tests/intel/xe_exec_fault_mode.c
+++ b/tests/intel/xe_exec_fault_mode.c
@@ -329,6 +329,17 @@ test_exec(int fd, struct drm_xe_engine_class_instance *eci,
 				igt_assert_eq(data[i].data, 0xc0ffee);
 	}
 
+	if ((flags & INVALID_FAULT)) {
+		for (i = 0; i < n_execs; i++) {
+			int ret;
+			int64_t timeout = NSEC_PER_SEC;
+
+			ret = __xe_wait_ufence(fd, &data[i].exec_sync, USER_FENCE_VALUE,
+					       exec_queues[i % n_exec_queues], &timeout);
+			igt_assert(ret == -EIO || ret ==0);

"ret ==0" - missing space.

Btw in theory we have n_execs * 1second  (128sec???) total wait time.

+		}
+	}
+

if ((flags & INVALID_FAULT)) {

 	for (i = 0; i < n_exec_queues; i++) {
 		xe_exec_queue_destroy(fd, exec_queues[i]);
 		if (bind_exec_queues[i])