use test -e to check if file exists

Signed-off-by: pengshanyu <[email protected]>

tests/ffi/dev-mem_not_present/PURPOSE

@@ -1,10 +1,10 @@
 Verifies that /dev/mem is not present in QM partition.
 
-This test execute `ls -l /dev/mem` (no other input) in QM partition:
-    podman exec -t qm bash -c "ls -l /dev/mem"
+This test execute `test -e /dev/mem &>/dev/null` in QM partition, no other input.
+    podman exec qm test -e /dev/mem &>/dev/null
 
 Expected result:
-    out: [ INFO  ] PASS: /dev/mem is not present in QM partition.
+    out: [ INFO  ] PASS: check_dev-mem_not_present: As expected, /dev/mem is not present in QM partition.
 
 Results location:
     /plans/e2e/ffi/report/default-0/junit.xml

tests/ffi/dev-mem_not_present/test.sh

@@ -4,17 +4,14 @@
 . ../../e2e/lib/utils
 
 check_dev-mem_not_present(){
-    expected_result="ls: cannot access '/dev/mem': No such file or directory"
-    return_from_cmd=$(podman exec -t qm bash -c "ls -l /dev/mem")
-
     # Check /dev/mem is not present in QM partition
-    if [[ $? != "0"  && "${return_from_cmd}" == "${expected_result}"* ]]; then
-        info_message "PASS: check_dev-mem_not_present: /dev/mem is not present in QM partition."
-        exit 0
-    else
-        info_message "Command 'ls -l /dev/mem' returns from QM partition: ${return_from_cmd}"
-        info_message "FAIL: check_dev-mem_not_present: Check /dev/mem is not present in QM partition failed."
+    if podman exec qm test -e /dev/mem &>/dev/null; then
+        info_message "Found /dev/mem in QM partition: $(podman exec -t qm ls -l /dev/mem)"
+        info_message "FAIL: check_dev-mem_not_present: Check for /dev/mem in QM partition failed, it should not present."
         exit 1
+    else
+        info_message "PASS: check_dev-mem_not_present: As expected, /dev/mem is not present in QM partition."
+        exit 0
     fi
 }