Author: sginsberg
Date: Fri Apr 6 20:13:33 2012
New Revision: 56333
URL: http://svn.reactos.org/svn/reactos?rev=56333&view=rev
Log:
- Even while I love having the trap/fpu/context code in C, the bugs this switch
introduced continue to amaze me. This time, fix a bug from 45156 when
KiFlushNPXState was rewritten in C. The C version could miss to restore the
interrupt state, which would lead to interrupts being disabled when it was not
expected. This "interrupt leak" was seen in the page fault handler if a page
fault occurred after interrupts had been disabled (which had sometimes been
observed to occur on the test server during exception handling and thread
creation when KiFlushNPXState had been called). This didn't completely hang the
system because during thread creation (and other system calls where this may
have happened) interrupts would be re-enabled when returning to user mode when
restoring eflags, and the exception handling would result in a system call
which would enable interrupts again (it appears exception handler would have
run with interrupts disabled, though!). This is now fixed, as well as any other
issues this might have caused. The hack in the page fault handler remains until
another issue has been fixed.
Modified:
trunk/reactos/ntoskrnl/ke/i386/cpu.c
Modified: trunk/reactos/ntoskrnl/ke/i386/cpu.c
URL:
http://svn.reactos.org/svn/reactos/trunk/reactos/ntoskrnl/ke/i386/cpu.c?rev=56333&r1=56332&r2=56333&view=diff
==============================================================================
--- trunk/reactos/ntoskrnl/ke/i386/cpu.c [iso-8859-1] (original)
+++ trunk/reactos/ntoskrnl/ke/i386/cpu.c [iso-8859-1] Fri Apr 6 20:13:33 2012
@@ -1323,7 +1323,12 @@
if (Thread->NpxState != NPX_STATE_LOADED)
{
/* If there's nothing to load, quit */
- if (!SaveArea) return;
+ if (!SaveArea)
+ {
+ /* Restore interrupt state and return */
+ __writeeflags(EFlags);
+ return;
+ }
/* Need FXSR support for this */
ASSERT(KeI386FxsrPresent == TRUE);
