x86/efi: Fixup faults from UEFI firmware
Firmware may try to access BOOT_SERVICES_* memory regions even
after those regions were surrendered the kernel for its own
consumption. Fix that up.
We are sure that we will not have false positives as those
memory regions are reserved and the kernel cannot use them.
Signed-off-by: Ricardo Neri <ricardo.neri-calderon@linux.intel.com>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c
index 8e57229..455787d 100644
--- a/arch/x86/mm/fault.c
+++ b/arch/x86/mm/fault.c
@@ -14,6 +14,7 @@
#include <linux/hugetlb.h> /* hstate_index_to_shift */
#include <linux/prefetch.h> /* prefetchw */
#include <linux/context_tracking.h> /* exception_enter(), ... */
+#include <linux/efi.h> /* fixup for buggy UEFI firmware*/
#include <asm/traps.h> /* dotraplinkage, ... */
#include <asm/pgalloc.h> /* pgd_*(), ... */
@@ -693,6 +694,13 @@
return;
/*
+ * Try to fixup faults caused by illegal access to BOOT_SERVICES_*
+ * regions by UEFI firmware.
+ */
+ if (efi_boot_services_fixup(address))
+ return;
+
+ /*
* Oops. The kernel tried to access some bad page. We'll have to
* terminate things with extreme prejudice:
*/
