[cgutman] 57065: [NTOSKRNL] - Fix a critical bug in interrupt handling that could result in HAL returning the current processor to the wrong IRQL after an interrupt is handled that requires a raise...

Author: cgutman
Date: Mon Aug 13 01:17:13 2012
New Revision: 57065

URL: http://svn.reactos.org/svn/reactos?rev=57065&view=rev
Log:
[NTOSKRNL]
- Fix a critical bug in interrupt handling that could result in HAL returning the current
processor to the wrong IRQL after an interrupt is handled that requires a raise to a
synchronize IRQL.

Modified:
    trunk/reactos/ntoskrnl/ke/i386/irqobj.c

Modified: trunk/reactos/ntoskrnl/ke/i386/irqobj.c
URL:
http://svn.reactos.org/svn/reactos/trunk/reactos/ntoskrnl/ke/i386/irqobj.c?…
==============================================================================
--- trunk/reactos/ntoskrnl/ke/i386/irqobj.c [iso-8859-1] (original)
+++ trunk/reactos/ntoskrnl/ke/i386/irqobj.c [iso-8859-1] Mon Aug 13 01:17:13 2012
@@ -229,7 +229,7 @@
 KiChainedDispatch(IN PKTRAP_FRAME TrapFrame,
                   IN PKINTERRUPT Interrupt)
 {
-    KIRQL OldIrql;
+    KIRQL OldIrql, OldInterruptIrql = 0;
     BOOLEAN Handled;
     PLIST_ENTRY NextEntry, ListHead;
 
@@ -250,7 +250,7 @@
             if (Interrupt->SynchronizeIrql > Interrupt->Irql)
             {
                 /* Raise to higher IRQL */
-                OldIrql = KfRaiseIrql(Interrupt->SynchronizeIrql);
+                OldInterruptIrql = KfRaiseIrql(Interrupt->SynchronizeIrql);
             }
         
             /* Acquire interrupt lock */
@@ -267,7 +267,8 @@
             if (Interrupt->SynchronizeIrql > Interrupt->Irql)
             {
                 /* Lower the IRQL back */
-                KfLowerIrql(OldIrql);
+                ASSERT(OldInterruptIrql == Interrupt->Irql);
+                KfLowerIrql(OldInterruptIrql);
             }
         
             /* Check if the interrupt got handled and it's level */