Add another page for kernel stack

1 files changed, 11 insertions, 2 deletions

diff --git a/src/core/paging.c b/src/core/paging.c
index cf5b951..243ed0b 100644
--- a/src/core/paging.c
+++ b/src/core/paging.c
@@ -108,15 +108,24 @@ int *paging_allocate(int p){
     int dir_entry=1; // Entry point is at 1024*4096=4194304 (page dir entry 1 and page table entry 0)
     int pt_entry=0;
     int p_current=max(1,p); // Allocate at least 1 page
+    p_current++; // Allocated one more page for the kernel stack (one per task)
     while(p_current!=0){
-        u_page_table[pt_entry]=(int)paging_allocate_next_page()|7;
+        u_page_table[pt_entry]=(int)paging_allocate_next_page();
+        if(p_current==1) // Kernel stack is the last page
+            u_page_table[pt_entry]|=3;
+        else
+            u_page_table[pt_entry]|=7;
         p_current--;
         pt_entry++;
         if(pt_entry%1024==0){
             dir_entry++;
             pt_entry=0;
             u_page_table=(int*)paging_allocate_next_page();
-            page_dir[dir_entry]=(int)u_page_table|7;
+            page_dir[dir_entry]=(int)u_page_table;
+            if(p_current==1) // Kernel stack is the last page (and might be in the last page directory entry)
+                 page_dir[dir_entry]|=3;
+            else
+                 page_dir[dir_entry]|=7;
         }
     }
     return page_dir;