[NTOS]: KiDispatchInterrupt crushes EBX, so maybe it should preserve it first? This only worked because KiDispatchInterrupt was only called by ASM code that already was magically aware of this fact, and preserved (or didn't use) EBX before making the call. Yuck!

svn path=/trunk/; revision=45212

reactos/ntoskrnl/ke/i386/trap.s

@@ -320,6 +320,9 @@ _KeUpdateSystemTime@0:
 .func KiDispatchInterrupt@0
 _KiDispatchInterrupt@0:
 
+    /* Preserve EBX */
+    push ebx
+
     /* Get the PCR  and disable interrupts */
     mov ebx, PCR[KPCR_SELF]
     cli
@@ -418,12 +421,14 @@ GetNext:
 
 Return:
     /* All done */
+    pop ebx
     ret
 
 QuantumEnd:
     /* Disable quantum end and process it */
     mov byte ptr [ebx+KPCR_PRCB_QUANTUM_END], 0
     call _KiQuantumEnd@0
+    pop ebx
     ret
 .endfunc