Merge tag 'v2.6.38' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6

[mv-sheeva.git] / arch / x86 / pci / pcbios.c

diff --git a/arch/x86/pci/pcbios.c b/arch/x86/pci/pcbios.c
index 2492d165096a2a696cf8332534966cfce2c848a7..a5f7d0d63de0def1481382f785d0fc34d553f0f6 100644 (file)
--- a/arch/x86/pci/pcbios.c
+++ b/arch/x86/pci/pcbios.c
@@ -9,6 +9,7 @@
 #include <linux/uaccess.h>
 #include <asm/pci_x86.h>
 #include <asm/pci-functions.h>
+#include <asm/cacheflush.h>
 
 /* BIOS32 signature: "_32_" */
 #define BIOS32_SIGNATURE       (('_' << 0) + ('3' << 8) + ('2' << 16) + ('_' << 24))
@@ -25,6 +26,27 @@
 #define PCIBIOS_HW_TYPE1_SPEC          0x10
 #define PCIBIOS_HW_TYPE2_SPEC          0x20
 
+int pcibios_enabled;
+
+/* According to the BIOS specification at:
+ * http://members.datafast.net.au/dft0802/specs/bios21.pdf, we could
+ * restrict the x zone to some pages and make it ro. But this may be
+ * broken on some bios, complex to handle with static_protections.
+ * We could make the 0xe0000-0x100000 range rox, but this can break
+ * some ISA mapping.
+ *
+ * So we let's an rw and x hole when pcibios is used. This shouldn't
+ * happen for modern system with mmconfig, and if you don't want it
+ * you could disable pcibios...
+ */
+static inline void set_bios_x(void)
+{
+       pcibios_enabled = 1;
+       set_memory_x(PAGE_OFFSET + BIOS_BEGIN, (BIOS_END - BIOS_BEGIN) >> PAGE_SHIFT);
+       if (__supported_pte_mask & _PAGE_NX)
+               printk(KERN_INFO "PCI : PCI BIOS aera is rw and x. Use pci=nobios if you want it NX.\n");
+}
+
 /*
  * This is the standard structure used to identify the entry point
  * to the BIOS32 Service Directory, as documented in
@@ -332,6 +354,7 @@ static struct pci_raw_ops * __devinit pci_find_bios(void)
                        DBG("PCI: BIOS32 Service Directory entry at 0x%lx\n",
                                        bios32_entry);
                        bios32_indirect.address = bios32_entry + PAGE_OFFSET;
+                       set_bios_x();
                        if (check_pcibios())
                                return &pci_bios_access;
                }