efi: Add kernel param efi=noruntime

noefi kernel param means actually disabling efi runtime, Per suggestion
from Leif Lindholm efi=noruntime should be better. But since noefi is
already used in X86 thus just adding another param efi=noruntime for
same purpose.

Signed-off-by: Dave Young <dyoung@redhat.com>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>

3 files changed, 13 insertions, 3 deletions

diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 08df275eee2b..d0e431611a04 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -992,13 +992,14 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
                         Format: {"off" | "on" | "skip[mbr]"}
 
         efi=            [EFI]
-                        Format: { "old_map", "nochunk" }
+                        Format: { "old_map", "nochunk", "noruntime" }
                         old_map [X86-64]: switch to the old ioremap-based EFI
                         runtime services mapping. 32-bit still uses this one by
                         default.
                         nochunk: disable reading files in "chunks" in the EFI
                         boot stub, as chunking can cause problems with some
                         firmware implementations.
+                        noruntime : disable EFI runtime services support
 
         efi_no_storage_paranoia [EFI; X86]
                         Using this parameter you can use more than 50% of
diff --git a/arch/x86/platform/efi/efi.c b/arch/x86/platform/efi/efi.c
index c73a7df5d37f..00f4cc566adb 100644
--- a/arch/x86/platform/efi/efi.c
+++ b/arch/x86/platform/efi/efi.c
@@ -930,11 +930,11 @@ u64 efi_mem_attributes(unsigned long phys_addr)
         return 0;
 }
 
-static int __init parse_efi_cmdline(char *str)
+static int __init arch_parse_efi_cmdline(char *str)
 {
         if (parse_option_str(str, "old_map"))
                 set_bit(EFI_OLD_MEMMAP, &efi.flags);
 
         return 0;
 }
-early_param("efi", parse_efi_cmdline);
+early_param("efi", arch_parse_efi_cmdline);
diff --git a/drivers/firmware/efi/efi.c b/drivers/firmware/efi/efi.c
index c8f01a73edb5..cebfa36a27ae 100644
--- a/drivers/firmware/efi/efi.c
+++ b/drivers/firmware/efi/efi.c
@@ -54,6 +54,15 @@ bool efi_runtime_disabled(void)
         return disable_runtime;
 }
 
+static int __init parse_efi_cmdline(char *str)
+{
+        if (parse_option_str(str, "noruntime"))
+                disable_runtime = true;
+
+        return 0;
+}
+early_param("efi", parse_efi_cmdline);
+
 static struct kobject *efi_kobj;
 static struct kobject *efivars_kobj;