diff options
| -rw-r--r-- | OvmfPkg/Library/NestedInterruptTplLib/Tpl.c | 10 |
1 files changed, 8 insertions, 2 deletions
diff --git a/OvmfPkg/Library/NestedInterruptTplLib/Tpl.c b/OvmfPkg/Library/NestedInterruptTplLib/Tpl.c index e19d98878e..e921a09c55 100644 --- a/OvmfPkg/Library/NestedInterruptTplLib/Tpl.c +++ b/OvmfPkg/Library/NestedInterruptTplLib/Tpl.c @@ -104,6 +104,7 @@ NestedInterruptRestoreTPL ( // defer our call to RestoreTPL() to the in-progress outer instance
// of the same interrupt handler.
//
+ ASSERT (GetInterruptState () == FALSE);
if (InterruptedTPL == IsrState->InProgressRestoreTPL) {
//
// Trigger outer instance of this interrupt handler to perform the
@@ -153,6 +154,7 @@ NestedInterruptRestoreTPL ( //
// Check shared state loop invariants.
//
+ ASSERT (GetInterruptState () == FALSE);
ASSERT (IsrState->InProgressRestoreTPL < InterruptedTPL);
ASSERT (IsrState->DeferredRestoreTPL == FALSE);
@@ -167,13 +169,17 @@ NestedInterruptRestoreTPL ( //
// Call RestoreTPL() to allow event notifications to be
- // dispatched. This will implicitly re-enable interrupts.
+ // dispatched. This will implicitly re-enable interrupts (if
+ // InterruptedTPL is below TPL_HIGH_LEVEL), even though we are
+ // still inside the interrupt handler.
//
gBS->RestoreTPL (InterruptedTPL);
//
// Re-disable interrupts after the call to RestoreTPL() to ensure
- // that we have exclusive access to the shared state.
+ // that we have exclusive access to the shared state. Interrupts
+ // will be re-enabled by the IRET or equivalent instruction when
+ // we subsequently return from the interrupt handler.
//
DisableInterrupts ();
|