- Fix flaw in win32k hardware message queue which used KMUTEX instead of
KMUTANT, thus double-disabling Kernel APCs during the parsing of the
queue, which would result in actually deliving hardware message
callbacks with Kernel APCs disabled when going to user-mode. This was
detected when my new user-mode callback rewrite added checks for this
situation, and it originally caused a bugcheck. Since the message queue
code is now fixed, the bugcheck has been re-enabled, hopefully no other
such violations will be detected (I was able to run/install firefox for
a couple of minutes and there was no APC_INDEX_MISMATCH crash). Fixes
bug 1272, and thanks to Filip for doing some late-night IRC analysis
with me.
Modified: trunk/reactos/ntoskrnl/ke/i386/usercall_asm.S
Modified: trunk/reactos/subsys/win32k/ntuser/msgqueue.c
_____
Modified: trunk/reactos/ntoskrnl/ke/i386/usercall_asm.S
--- trunk/reactos/ntoskrnl/ke/i386/usercall_asm.S 2006-01-14
04:32:37 UTC (rev 20845)
+++ trunk/reactos/ntoskrnl/ke/i386/usercall_asm.S 2006-01-14
08:49:10 UTC (rev 20846)
@@ -87,7 +87,6 @@
AtPassive:
-#if 0
/* Make sure that we are not attached and that APCs are not
disabled */
movzx eax, byte ptr [ebx+KTHREAD_APC_STATE_INDEX]
mov edx, [ebx+KTHREAD_COMBINED_APC_DISABLE]
@@ -104,7 +103,6 @@
push 0
push APC_INDEX_MISMATCH
call _KeBugCheckEx@20
-#endif
ApcsEnabled:
#endif
_____
Modified: trunk/reactos/subsys/win32k/ntuser/msgqueue.c
--- trunk/reactos/subsys/win32k/ntuser/msgqueue.c 2006-01-14
04:32:37 UTC (rev 20845)
+++ trunk/reactos/subsys/win32k/ntuser/msgqueue.c 2006-01-14
08:49:10 UTC (rev 20846)
@@ -46,7 +46,7 @@
static ULONG volatile HardwareMessageQueueStamp = 0;
static LIST_ENTRY HardwareMessageQueueHead;
-static KMUTEX HardwareMessageQueueLock;
+static KMUTANT HardwareMessageQueueLock;
static KEVENT HardwareMessageEvent;
@@ -60,7 +60,7 @@
KeReleaseSpinLock(&SystemMessageQueueLock, OldIrql)
#define IntUnLockSystemHardwareMessageQueueLock(Wait) \
- KeReleaseMutex(&HardwareMessageQueueLock, Wait)
+ KeReleaseMutant(&HardwareMessageQueueLock, IO_NO_INCREMENT, FALSE,
Wait)
/* FUNCTIONS
*****************************************************************/
@@ -122,7 +122,7 @@
InitializeListHead(&HardwareMessageQueueHead);
KeInitializeEvent(&HardwareMessageEvent, NotificationEvent, 0);
KeInitializeSpinLock(&SystemMessageQueueLock);
- KeInitializeMutex(&HardwareMessageQueueLock, 0);
+ KeInitializeMutant(&HardwareMessageQueueLock, 0);
ExInitializePagedLookasideList(&MessageLookasideList,
NULL,