Hi Robert,

In the present patch the verification of elapsed time is failing.
The patch will need additional changes as below (bolded):

diff --git a/uefi-sct/SctPkg/TestCase/UEFI/EFI/BootServices/MiscBootServices/BlackBoxTest/MiscBootServicesBBTestFunction.c b/uefi-sct/SctPkg/TestCase/UEFI/EFI/BootServices/MiscBootServices/BlackBoxTest/MiscBootServicesBBTestFunction.c
index ad72646b..f3d189bd 100644
--- a/uefi-sct/SctPkg/TestCase/UEFI/EFI/BootServices/MiscBootServices/BlackBoxTest/MiscBootServicesBBTestFunction.c
+++ b/uefi-sct/SctPkg/TestCase/UEFI/EFI/BootServices/MiscBootServices/BlackBoxTest/MiscBootServicesBBTestFunction.c
@@ -827,7 +827,7 @@ BBTestStallInterfaceTest (
StartTime = Epoch;
OldTpl = gtBS->RaiseTPL (TplArray[Index]);
Status = gtBS->Stall (
-                     10000000
+                     4000000^M
);
gtBS->RestoreTPL (OldTpl);
if (gtRT->GetTime (&EndTime, NULL) != EFI_SUCCESS)
@@ -845,7 +845,7 @@ BBTestStallInterfaceTest (
(Index == 1? \
gMiscBootServicesBBTestFunctionAssertionGuid021: \
gMiscBootServicesBBTestFunctionAssertionGuid022),
-                   L"BS.Stall - 10 seconds",
*+                   L"BS.Stall - 4 seconds",^M*
L"%a:%d:Status - %r, TPL - %d",
__FILE__,
(UINTN)__LINE__,
@@ -853,8 +853,8 @@ BBTestStallInterfaceTest (
TplArray[Index]
);
SecondsElapsed = GetSecondsElapsed (&StartTime, &EndTime);
-    if ((SecondsElapsed <= 10 + MAX_SECOND_MARGIN) &&
-         (SecondsElapsed >= 10 - MAX_SECOND_MARGIN)) {
*+    if ((SecondsElapsed <= 4 + MAX_SECOND_MARGIN) &&^M*
*+         (SecondsElapsed >= 4 - MAX_SECOND_MARGIN)) {^M*
AssertionType = EFI_TEST_ASSERTION_PASSED;
} else {
AssertionType = EFI_TEST_ASSERTION_FAILED;
diff --git a/uefi-sct/SctPkg/TestCase/UEFI/EFI/BootServices/MiscBootServices/BlackBoxTest/MiscBootServicesBBTestMain.h b/uefi-sct/SctPkg/TestCase/UEFI/EFI/BootServices/MiscBootServices/BlackBoxTest/MiscBootServicesBBTestMain.h
index 9e98ec01..4f8eaa4c 100644
--- a/uefi-sct/SctPkg/TestCase/UEFI/EFI/BootServices/MiscBootServices/BlackBoxTest/MiscBootServicesBBTestMain.h
+++ b/uefi-sct/SctPkg/TestCase/UEFI/EFI/BootServices/MiscBootServices/BlackBoxTest/MiscBootServicesBBTestMain.h
@@ -46,7 +46,7 @@ typedef struct _RESET_DATA {
{ 0xA6033499, 0xE4AF, 0x44f5, {0x9D, 0x16, 0x30, 0x78, 0xD8, 0x61, 0x32, 0x28 }}

#define TPL_ARRAY_SIZE 3
-#define MAX_SECOND_MARGIN 2
+#define MAX_SECOND_MARGIN 1^M

//
// Change size from TPL_ARRAY_SIZE to TPL_ARRAY_SIZE + 1

I have verified the new changes and it executes fine.
Also uploaded the changes to bugzilla 4105 – SctPkg: Stall_Func test can cause disk timeouts and testing failure (tianocore.org) ( https://bugzilla.tianocore.org/show_bug.cgi?id=4105 )
You could please also check and reply.

With Warm Regards,

Edhay