Merge tag 'efi-for-3.7' of git://git.kernel.org/pub/scm/linux/kernel/git/mfleming/efi into x86/urgent

Pull EFI fixes from Matt Fleming:

 "Fix oops with EFI variables on mixed 32/64-bit firmware/kernels and
  document EFI git repository location on kernel.org."

Conflicts:
	arch/x86/include/asm/efi.h

Signed-off-by: Ingo Molnar <mingo@kernel.org>

4 files changed, 24 insertions, 8 deletions

diff --git a/MAINTAINERS b/MAINTAINERS
index 027ec2bfa135..f39a82dc0260 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -2802,6 +2802,7 @@ F:	sound/usb/misc/ua101.c
 EXTENSIBLE FIRMWARE INTERFACE (EFI)
 M:	Matt Fleming <matt.fleming@intel.com>
 L:	linux-efi@vger.kernel.org
+T:	git git://git.kernel.org/pub/scm/linux/kernel/git/mfleming/efi.git
 S:	Maintained
 F:	Documentation/x86/efi-stub.txt
 F:	arch/ia64/kernel/efi.c
diff --git a/arch/x86/include/asm/efi.h b/arch/x86/include/asm/efi.h
index 36ff332da130..6e8fdf5ad113 100644
--- a/arch/x86/include/asm/efi.h
+++ b/arch/x86/include/asm/efi.h
@@ -98,6 +98,7 @@ extern void efi_set_executable(efi_memory_desc_t *md, bool executable);
 extern int efi_memblock_x86_reserve_range(void);
 extern void efi_call_phys_prelog(void);
 extern void efi_call_phys_epilog(void);
+extern void efi_unmap_memmap(void);
 extern void efi_memory_uc(u64 addr, unsigned long size);
 
 #ifndef CONFIG_EFI
diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
index 5d888af8682a..ca45696f30fb 100644
--- a/arch/x86/kernel/setup.c
+++ b/arch/x86/kernel/setup.c
@@ -1049,6 +1049,18 @@ void __init setup_arch(char **cmdline_p)
 	arch_init_ideal_nops();
 
 	register_refined_jiffies(CLOCK_TICK_RATE);
+
+#ifdef CONFIG_EFI
+	/* Once setup is done above, disable efi_enabled on mismatched
+	 * firmware/kernel archtectures since there is no support for
+	 * runtime services.
+	 */
+	if (efi_enabled && IS_ENABLED(CONFIG_X86_64) != efi_64bit) {
+		pr_info("efi: Setup done, disabling due to 32/64-bit mismatch\n");
+		efi_unmap_memmap();
+		efi_enabled = 0;
+	}
+#endif
 }
 
 #ifdef CONFIG_X86_32
diff --git a/arch/x86/platform/efi/efi.c b/arch/x86/platform/efi/efi.c
index cb34839c97c5..ad4439145f85 100644
--- a/arch/x86/platform/efi/efi.c
+++ b/arch/x86/platform/efi/efi.c
@@ -70,11 +70,15 @@ EXPORT_SYMBOL(efi);
 struct efi_memory_map memmap;
 
 bool efi_64bit;
-static bool efi_native;
 
 static struct efi efi_phys __initdata;
 static efi_system_table_t efi_systab __initdata;
 
+static inline bool efi_is_native(void)
+{
+	return IS_ENABLED(CONFIG_X86_64) == efi_64bit;
+}
+
 static int __init setup_noefi(char *arg)
 {
 	efi_enabled = 0;
@@ -420,7 +424,7 @@ void __init efi_reserve_boot_services(void)
 	}
 }
 
-static void __init efi_unmap_memmap(void)
+void __init efi_unmap_memmap(void)
 {
 	if (memmap.map) {
 		early_iounmap(memmap.map, memmap.nr_map * memmap.desc_size);
@@ -432,7 +436,7 @@ void __init efi_free_boot_services(void)
 {
 	void *p;
 
-	if (!efi_native)
+	if (!efi_is_native())
 		return;
 
 	for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
@@ -684,12 +688,10 @@ void __init efi_init(void)
 		return;
 	}
 	efi_phys.systab = (efi_system_table_t *)boot_params.efi_info.efi_systab;
-	efi_native = !efi_64bit;
 #else
 	efi_phys.systab = (efi_system_table_t *)
 			  (boot_params.efi_info.efi_systab |
 			  ((__u64)boot_params.efi_info.efi_systab_hi<<32));
-	efi_native = efi_64bit;
 #endif
 
 	if (efi_systab_init(efi_phys.systab)) {
@@ -723,7 +725,7 @@ void __init efi_init(void)
 	 * that doesn't match the kernel 32/64-bit mode.
 	 */
 
-	if (!efi_native)
+	if (!efi_is_native())
 		pr_info("No EFI runtime due to 32/64-bit mismatch with kernel\n");
 	else if (efi_runtime_init()) {
 		efi_enabled = 0;
@@ -735,7 +737,7 @@ void __init efi_init(void)
 		return;
 	}
 #ifdef CONFIG_X86_32
-	if (efi_native) {
+	if (efi_is_native()) {
 		x86_platform.get_wallclock = efi_get_time;
 		x86_platform.set_wallclock = efi_set_rtc_mmss;
 	}
@@ -844,7 +846,7 @@ void __init efi_enter_virtual_mode(void)
 	 * non-native EFI
 	 */
 
-	if (!efi_native) {
+	if (!efi_is_native()) {
 		efi_unmap_memmap();
 		return;
 	}