2 files changed, 18 insertions, 3 deletions

diff --git a/arch/i386/kernel/e820.c b/arch/i386/kernel/e820.c
index b755255f2721..b704790f7969 100644
--- a/arch/i386/kernel/e820.c
+++ b/arch/i386/kernel/e820.c
@@ -9,6 +9,7 @@
 #include <linux/mm.h>
 #include <linux/efi.h>
 #include <linux/pfn.h>
+#include <linux/uaccess.h>
 
 #include <asm/pgtable.h>
 #include <asm/page.h>
@@ -155,7 +156,14 @@ static struct resource standard_io_resources[] = { {
         .flags  = IORESOURCE_BUSY | IORESOURCE_IO
 } };
 
-#define romsignature(x) (*(unsigned short *)(x) == 0xaa55)
+static int romsignature(const unsigned char *x)
+{
+        unsigned short sig;
+        int ret = 0;
+        if (probe_kernel_address((const unsigned short *)x, sig) == 0)
+                ret = (sig == 0xaa55);
+        return ret;
+}
 
 static int __init romchecksum(unsigned char *rom, unsigned long length)
 {
diff --git a/arch/i386/pci/pcbios.c b/arch/i386/pci/pcbios.c
index ed1512a175ab..5f5193401bea 100644
--- a/arch/i386/pci/pcbios.c
+++ b/arch/i386/pci/pcbios.c
@@ -5,6 +5,7 @@
 #include <linux/pci.h>
 #include <linux/init.h>
 #include <linux/module.h>
+#include <linux/uaccess.h>
 #include "pci.h"
 #include "pci-functions.h"
 
@@ -314,6 +315,10 @@ static struct pci_raw_ops * __devinit pci_find_bios(void)
         for (check = (union bios32 *) __va(0xe0000);
              check <= (union bios32 *) __va(0xffff0);
              ++check) {
+                long sig;
+                if (probe_kernel_address(&check->fields.signature, sig))
+                        continue;
+
                 if (check->fields.signature != BIOS32_SIGNATURE)
                         continue;
                 length = check->fields.length * 16;
@@ -331,11 +336,13 @@ static struct pci_raw_ops * __devinit pci_find_bios(void)
                 }
                 DBG("PCI: BIOS32 Service Directory structure at 0x%p\n", check);
                 if (check->fields.entry >= 0x100000) {
-                        printk("PCI: BIOS32 entry (0x%p) in high memory, cannot use.\n", check);
+                        printk("PCI: BIOS32 entry (0x%p) in high memory, "
+                                        "cannot use.\n", check);
                         return NULL;
                 } else {
                         unsigned long bios32_entry = check->fields.entry;
-                        DBG("PCI: BIOS32 Service Directory entry at 0x%lx\n", bios32_entry);
+                        DBG("PCI: BIOS32 Service Directory entry at 0x%lx\n",
+                                        bios32_entry);
                         bios32_indirect.address = bios32_entry + PAGE_OFFSET;
                         if (check_pcibios())
                                 return &pci_bios_access;