[IA64] Fill holes in FIXADDR_USER space with zero pages.
[linux-2.6.git] / arch / ia64 / mm / init.c
index 547785e..4eb2f52 100644 (file)
@@ -305,8 +305,9 @@ setup_gate (void)
        struct page *page;
 
        /*
-        * Map the gate page twice: once read-only to export the ELF headers etc. and once
-        * execute-only page to enable privilege-promotion via "epc":
+        * Map the gate page twice: once read-only to export the ELF
+        * headers etc. and once execute-only page to enable
+        * privilege-promotion via "epc":
         */
        page = virt_to_page(ia64_imva(__start_gate_section));
        put_kernel_page(page, GATE_ADDR, PAGE_READONLY);
@@ -315,6 +316,20 @@ setup_gate (void)
        put_kernel_page(page, GATE_ADDR + PAGE_SIZE, PAGE_GATE);
 #else
        put_kernel_page(page, GATE_ADDR + PERCPU_PAGE_SIZE, PAGE_GATE);
+       /* Fill in the holes (if any) with read-only zero pages: */
+       {
+               unsigned long addr;
+
+               for (addr = GATE_ADDR + PAGE_SIZE;
+                    addr < GATE_ADDR + PERCPU_PAGE_SIZE;
+                    addr += PAGE_SIZE)
+               {
+                       put_kernel_page(ZERO_PAGE(0), addr,
+                                       PAGE_READONLY);
+                       put_kernel_page(ZERO_PAGE(0), addr + PERCPU_PAGE_SIZE,
+                                       PAGE_READONLY);
+               }
+       }
 #endif
        ia64_patch_gate();
 }