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Don't let page containing stack disappear when switching memory spaces

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svn path=/trunk/; revision=4656
This commit is contained in:
Gé van Geldorp 2003-05-07 21:41:03 +00:00
parent 74c0e6eb1c
commit 5966a211e9
3 changed files with 38 additions and 4 deletions
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1
reactos/ntoskrnl/include/internal/mm.h
View file

@ -218,6 +218,7 @@ MmDeleteVirtualMapping(struct _EPROCESS* Process,
BOOL FreePage,
BOOL* WasDirty,
PHYSICAL_ADDRESS* PhysicalPage);
VOID MmUpdatePageDir(PULONG LocalPageDir);
#define MM_PAGE_CLEAN (0)
#define MM_PAGE_DIRTY (1)

20
reactos/ntoskrnl/ke/process.c
View file

@ -16,7 +16,7 @@
* along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
/* $Id: process.c,v 1.11 2002/09/08 10:23:29 chorns Exp $
/* $Id: process.c,v 1.12 2003/05/07 21:41:03 gvg Exp $
*
* PROJECT: ReactOS kernel
* FILE: ntoskrnl/ke/process.c
@ -44,6 +44,7 @@ KeAttachProcess (PEPROCESS Process)
{
KIRQL oldlvl;
PETHREAD CurrentThread;
PULONG AttachedProcessPageDir;
ULONG PageDir;
DPRINT("KeAttachProcess(Process %x)\n",Process);
@ -57,10 +58,23 @@ KeAttachProcess (PEPROCESS Process)
}
KeRaiseIrql(DISPATCH_LEVEL, &oldlvl);
/* The stack of the current process may be located in a page which is
not present in the page directory of the process we're attaching to.
That would lead to a page fault when this function returns. However,
since the processor can't call the page fault handler 'cause it can't
push EIP on the stack, this will show up as a stack fault which will
crash the entire system.
To prevent this, make sure the page directory of the process we're
attaching to is up-to-date. */
AttachedProcessPageDir = ExAllocatePageWithPhysPage(Process->Pcb.DirectoryTableBase);
MmUpdatePageDir(AttachedProcessPageDir);
ExUnmapPage(AttachedProcessPageDir);
CurrentThread->OldProcess = PsGetCurrentProcess();
CurrentThread->ThreadsProcess = Process;
PageDir = CurrentThread->ThreadsProcess->Pcb.DirectoryTableBase.u.LowPart;
PageDir = Process->Pcb.DirectoryTableBase.u.LowPart;
DPRINT("Switching process context to %x\n",PageDir)
__asm__("movl %0,%%cr3\n\t"
: /* no inputs */

21
reactos/ntoskrnl/mm/i386/page.c
View file

@ -16,7 +16,7 @@
* along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
/* $Id: page.c,v 1.47 2002/11/05 21:13:15 dwelch Exp $
/* $Id: page.c,v 1.48 2003/05/07 21:41:03 gvg Exp $
*
* PROJECT: ReactOS kernel
* FILE: ntoskrnl/mm/i386/page.c
@ -1213,4 +1213,23 @@ MmGetPhysicalAddress(PVOID vaddr)
}
VOID
MmUpdatePageDir(PULONG LocalPageDir)
{
unsigned Entry;
for (Entry = ADDR_TO_PDE_OFFSET(KERNEL_BASE);
Entry < PAGE_SIZE / sizeof(LONG);
Entry++)
{
/* Skip the page directory */
if (ADDR_TO_PDE_OFFSET(PAGETABLE_MAP) != Entry &&
0 == LocalPageDir[Entry] &&
0 != MmGlobalKernelPageDirectory[Entry])
{
LocalPageDir[Entry] = MmGlobalKernelPageDirectory[Entry];
}
}
}
/* EOF */