From 653d79d1290445018ca7ad34ffa1afc3812b9f5b Mon Sep 17 00:00:00 2001
From: Hartmut Birr <osexpert@googlemail.com>
Date: Sat, 12 Mar 2005 09:14:38 +0000
Subject: [PATCH] Lock the kernel address space instead the process' one, if
 the pages are located in kernel space. Unlock the address space on error.

svn path=/trunk/; revision=13963
---
 reactos/ntoskrnl/mm/mdl.c | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/reactos/ntoskrnl/mm/mdl.c b/reactos/ntoskrnl/mm/mdl.c
index e3d7c2a44de..934080c06a4 100644
--- a/reactos/ntoskrnl/mm/mdl.c
+++ b/reactos/ntoskrnl/mm/mdl.c
@@ -361,6 +361,7 @@ VOID STDCALL MmProbeAndLockPages (PMDL Mdl,
    KPROCESSOR_MODE Mode;
    PFN_TYPE Page;
    PEPROCESS CurrentProcess = PsGetCurrentProcess();
+   PMADDRESS_SPACE AddressSpace;
 
    DPRINT("MmProbeAndLockPages(Mdl %x)\n", Mdl);
 
@@ -394,19 +395,21 @@ VOID STDCALL MmProbeAndLockPages (PMDL Mdl,
       //FIXME: why isn't AccessMode used?
       Mode = KernelMode;
       Mdl->Process = NULL;
+      AddressSpace = MmGetKernelAddressSpace();
    }
    else
    {
       //FIXME: why isn't AccessMode used?
       Mode = UserMode;
       Mdl->Process = CurrentProcess;      
+      AddressSpace = &CurrentProcess->AddressSpace;
    }
 
 
    /*
     * Lock the pages
     */
-   MmLockAddressSpace(&CurrentProcess->AddressSpace);
+   MmLockAddressSpace(AddressSpace);
 
    for (i = 0; i < NrPages; i++)
    {
@@ -430,6 +433,7 @@ VOID STDCALL MmProbeAndLockPages (PMDL Mdl,
                MmUnlockPage(Page);
                MmDereferencePage(Page);
             }
+            MmUnlockAddressSpace(AddressSpace);
             ExRaiseStatus(Status);
          }
       }
@@ -450,6 +454,7 @@ VOID STDCALL MmProbeAndLockPages (PMDL Mdl,
                MmUnlockPage(Page);
                MmDereferencePage(Page);
             }
+            MmUnlockAddressSpace(AddressSpace);
             ExRaiseStatus(Status);
          }
       }
@@ -458,7 +463,7 @@ VOID STDCALL MmProbeAndLockPages (PMDL Mdl,
       MmReferencePage(Page);
    }
    
-   MmUnlockAddressSpace(&CurrentProcess->AddressSpace);
+   MmUnlockAddressSpace(AddressSpace);
    Mdl->MdlFlags |= MDL_PAGES_LOCKED;
 }