1 files changed, 35 insertions, 20 deletions

diff --git a/arch/i386/mm/fault.c b/arch/i386/mm/fault.c
index b8c4e259fc8b..c6a0a06258e6 100644
--- a/arch/i386/mm/fault.c
+++ b/arch/i386/mm/fault.c
@@ -20,6 +20,7 @@
 #include <linux/tty.h>
 #include <linux/vt_kern.h>              /* For unblank_screen() */
 #include <linux/highmem.h>
+#include <linux/bootmem.h>              /* for max_low_pfn */
 #include <linux/module.h>
 #include <linux/kprobes.h>
 #include <linux/uaccess.h>
@@ -301,7 +302,6 @@ fastcall void __kprobes do_page_fault(struct pt_regs *regs,
         struct mm_struct *mm;
         struct vm_area_struct * vma;
         unsigned long address;
-        unsigned long page;
         int write, si_code;
 
         /* get the address */
@@ -510,7 +510,9 @@ no_context:
         bust_spinlocks(1);
 
         if (oops_may_print()) {
-        #ifdef CONFIG_X86_PAE
+                __typeof__(pte_val(__pte(0))) page;
+
+#ifdef CONFIG_X86_PAE
                 if (error_code & 16) {
                         pte_t *pte = lookup_address(address);
 
@@ -519,7 +521,7 @@ no_context:
                                         "NX-protected page - exploit attempt? "
                                         "(uid: %d)\n", current->uid);
                 }
-        #endif
+#endif
                 if (address < PAGE_SIZE)
                         printk(KERN_ALERT "BUG: unable to handle kernel NULL "
                                         "pointer dereference");
@@ -529,25 +531,38 @@ no_context:
                 printk(" at virtual address %08lx\n",address);
                 printk(KERN_ALERT " printing eip:\n");
                 printk("%08lx\n", regs->eip);
-        }
-        page = read_cr3();
-        page = ((unsigned long *) __va(page))[address >> 22];
-        if (oops_may_print())
+
+                page = read_cr3();
+                page = ((__typeof__(page) *) __va(page))[address >> PGDIR_SHIFT];
+#ifdef CONFIG_X86_PAE
+                printk(KERN_ALERT "*pdpt = %016Lx\n", page);
+                if ((page >> PAGE_SHIFT) < max_low_pfn
+                    && page & _PAGE_PRESENT) {
+                        page &= PAGE_MASK;
+                        page = ((__typeof__(page) *) __va(page))[(address >> PMD_SHIFT)
+                                                                 & (PTRS_PER_PMD - 1)];
+                        printk(KERN_ALERT "*pde = %016Lx\n", page);
+                        page &= ~_PAGE_NX;
+                }
+#else
                 printk(KERN_ALERT "*pde = %08lx\n", page);
-        /*
-         * We must not directly access the pte in the highpte
-         * case, the page table might be allocated in highmem.
-         * And lets rather not kmap-atomic the pte, just in case
-         * it's allocated already.
-         */
-#ifndef CONFIG_HIGHPTE
-        if ((page & 1) && oops_may_print()) {
-                page &= PAGE_MASK;
-                address &= 0x003ff000;
-                page = ((unsigned long *) __va(page))[address >> PAGE_SHIFT];
-                printk(KERN_ALERT "*pte = %08lx\n", page);
-        }
 #endif
+
+                /*
+                 * We must not directly access the pte in the highpte
+                 * case if the page table is located in highmem.
+                 * And let's rather not kmap-atomic the pte, just in case
+                 * it's allocated already.
+                 */
+                if ((page >> PAGE_SHIFT) < max_low_pfn
+                    && (page & _PAGE_PRESENT)) {
+                        page &= PAGE_MASK;
+                        page = ((__typeof__(page) *) __va(page))[(address >> PAGE_SHIFT)
+                                                                 & (PTRS_PER_PTE - 1)];
+                        printk(KERN_ALERT "*pte = %0*Lx\n", sizeof(page)*2, (u64)page);
+                }
+        }
+
         tsk->thread.cr2 = address;
         tsk->thread.trap_no = 14;
         tsk->thread.error_code = error_code;