Kernel/x86_64 - Debugging GUI errors (and a wild goose chase)

[tpg/acess2.git] / KernelLand / Kernel / arch / x86_64 / mm_virt.c

diff --git a/KernelLand/Kernel/arch/x86_64/mm_virt.c b/KernelLand/Kernel/arch/x86_64/mm_virt.c
index e1e59c0..de7ae52 100644 (file)
--- a/KernelLand/Kernel/arch/x86_64/mm_virt.c
+++ b/KernelLand/Kernel/arch/x86_64/mm_virt.c
@@ -722,43 +722,73 @@ int MM_IsValidBuffer(tVAddr Addr, size_t Size)
 
        Size += Addr & (PAGE_SIZE-1);
        Addr &= ~(PAGE_SIZE-1);
-       Addr &= ((1UL << 48)-1);        // Clap to address space
+       // NC addr
+       if( ((Addr >> 47) & 1) != ((Addr>>48) == 0xFFFF))
+               return 0;
+       Addr &= ((1UL << 48)-1);        // Clamp to address space
 
        pml4 = Addr >> 39;
        pdp = Addr >> 30;
        dir = Addr >> 21;
        tab = Addr >> 12;
 
-       if( !(PAGEMAPLVL4(pml4) & 1) )  return 0;
-       if( !(PAGEDIRPTR(pdp) & 1) )    return 0;
-       if( !(PAGEDIR(dir) & 1) )       return 0;
-       if( !(PAGETABLE(tab) & 1) )     return 0;
+       if( !(PAGEMAPLVL4(pml4) & 1) ) {
+               Log_Debug("MMVirt", "PML4E %i NP", pml4);
+               return 0;
+       }
+       if( !(PAGEDIRPTR(pdp) & 1) ) {
+               Log_Debug("MMVirt", "PDPE %i NP", pdp);
+               return 0;
+       }
+       if( !(PAGEDIR(dir) & 1) ) {
+               Log_Debug("MMVirt", "PDE %i NP", dir);
+               return 0;
+       }
+       if( !(PAGETABLE(tab) & 1) ) {
+               Log_Debug("MMVirt", "PTE %i NP", tab);
+               return 0;
+       }
        
        bIsUser = !!(PAGETABLE(tab) & PF_USER);
 
        while( Size >= PAGE_SIZE )
        {
+               tab ++;
+               Size -= PAGE_SIZE;
+               
                if( (tab & 511) == 0 )
                {
                        dir ++;
-                       if( ((dir >> 9) & 511) == 0 )
+                       if( (dir & 511) == 0 )
                        {
                                pdp ++;
-                               if( ((pdp >> 18) & 511) == 0 )
+                               if( (pdp & 511) == 0 )
                                {
                                        pml4 ++;
-                                       if( !(PAGEMAPLVL4(pml4) & 1) )  return 0;
+                                       if( !(PAGEMAPLVL4(pml4) & 1) ) {
+                                               Log_Debug("MMVirt", "IsValidBuffer - PML4E %x NP, Size=%x", pml4, Size);
+                                               return 0;
+                                       }
+                               }
+                               if( !(PAGEDIRPTR(pdp) & 1) ) {
+                                       Log_Debug("MMVirt", "IsValidBuffer - PDPE %x NP", pdp);
+                                       return 0;
                                }
-                               if( !(PAGEDIRPTR(pdp) & 1) )    return 0;
                        }
-                       if( !(PAGEDIR(dir) & 1) )       return 0;
+                       if( !(PAGEDIR(dir) & 1) ) {
+                               Log_Debug("MMVirt", "IsValidBuffer - PDE %x NP", dir);
+                               return 0;
+                       }
                }
                
-               if( !(PAGETABLE(tab) & 1) )   return 0;
-               if( bIsUser && !(PAGETABLE(tab) & PF_USER) )    return 0;
-
-               tab ++;
-               Size -= PAGE_SIZE;
+               if( !(PAGETABLE(tab) & 1) ) {
+                       Log_Debug("MMVirt", "IsValidBuffer - PTE %x NP", tab);
+                       return 0;
+               }
+               if( bIsUser && !(PAGETABLE(tab) & PF_USER) ) {
+                       Log_Debug("MMVirt", "IsValidBuffer - PTE %x Not user", tab);
+                       return 0;
+               }
        }
        return 1;
 }
@@ -894,7 +924,7 @@ void MM_FreeTemp(void *Ptr)
 
 
 // --- Address Space Clone --
-tPAddr MM_Clone(void)
+tPAddr MM_Clone(int bNoUserCopy)
 {
        tPAddr  ret;
         int    i;
@@ -910,7 +940,7 @@ tPAddr MM_Clone(void)
        INVLPG_ALL();
        
        // #3 Set Copy-On-Write to all user pages
-       if( Threads_GetPID() != 0 )
+       if( Threads_GetPID() != 0 && !bNoUserCopy )
        {
                for( i = 0; i < 256; i ++)
                {