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[NTOSKRNL]

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- Handle VME for the PUSHF and POPF instruction in virtual mode
 - There is no reason to set interrupt flag when handling POPF
 - Fix a typo in POPF case : mask out the right variable
See http://www.rcollins.org/articles/vme1/ for reference

svn path=/trunk/; revision=58852
This commit is contained in:
Jérôme Gardou 2013-04-25 21:29:59 +00:00
parent b4fe8f646f
commit 990171235d
1 changed files with 24 additions and 8 deletions
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32
reactos/ntoskrnl/ke/i386/v86vdm.c
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@ -53,16 +53,22 @@ KiVdmOpcodePUSHF(IN PKTRAP_FRAME TrapFrame,
{
ULONG Esp, V86EFlags, TrapEFlags;
/* Check for VME support */
ASSERT(KeI386VirtualIntExtensions == FALSE);
/* Get current V8086 flags and mask out interrupt flag */
V86EFlags = *KiNtVdmState;
V86EFlags &= ~EFLAGS_INTERRUPT_MASK;
/* Get trap frame EFLags and leave only align, nested task and interrupt */
/* Get trap frame EFLags */
TrapEFlags = TrapFrame->EFlags;
V86EFlags &= (EFLAGS_ALIGN_CHECK | EFLAGS_NESTED_TASK | EFLAGS_INTERRUPT_MASK);
/* Check for VME support */
if(KeI386VirtualIntExtensions)
{
/* Copy the virtual interrupt flag to the interrupt flag */
TrapEFlags &= ~EFLAGS_INTERRUPT_MASK;
if(TrapEFlags & EFLAGS_VIF)
TrapEFlags |= EFLAGS_INTERRUPT_MASK;
}
/* Leave only align, nested task and interrupt */
TrapEFlags &= (EFLAGS_ALIGN_CHECK | EFLAGS_NESTED_TASK | EFLAGS_INTERRUPT_MASK);
/* Add in those flags if they exist, and add in the IOPL flag */
V86EFlags |= TrapEFlags;
@ -133,10 +139,20 @@ KiVdmOpcodePOPF(IN PKTRAP_FRAME TrapFrame,
TrapEFlags = TrapFrame->EFlags;
/* Check for VME support */
ASSERT(KeI386VirtualIntExtensions == FALSE);
if(KeI386VirtualIntExtensions)
{
/* Copy the IF flag into the VIF one */
V86EFlags &= ~EFLAGS_VIF;
if(V86EFlags & EFLAGS_INTERRUPT_MASK)
{
V86EFlags |= EFLAGS_VIF;
/* Don't set the interrupt flag */
V86EFlags &= ~EFLAGS_INTERRUPT_MASK;
}
}
/* Add V86 and Interrupt flag */
V86EFlags |= EFLAGS_V86_MASK | EFLAGS_INTERRUPT_MASK;
/* Add V86 flag */
V86EFlags |= EFLAGS_V86_MASK;
/* Update EFlags in trap frame */
TrapFrame->EFlags = V86EFlags;