[tip:efi/core] efi/arm*: Take the Memory Attributes table into account

[tip-bot for Ard Biesheuvel]

Commit-ID:  789957ef72f976cb325e9057225fc4e9c4513060
Gitweb:     http://git.kernel.org/tip/789957ef72f976cb325e9057225fc4e9c4513060
Author:     Ard Biesheuvel <ard.biesheuvel@xxxxxxxxxx>
AuthorDate: Mon, 25 Apr 2016 21:06:46 +0100
Committer:  Ingo Molnar <mingo@xxxxxxxxxx>
CommitDate: Thu, 28 Apr 2016 11:33:55 +0200

efi/arm*: Take the Memory Attributes table into account

Call into the generic memory attributes table support code at the
appropriate times during the init sequence so that the UEFI Runtime
Services region are mapped according to the strict permissions it
specifies.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@xxxxxxxxxx>
Signed-off-by: Matt Fleming <matt@xxxxxxxxxxxxxxxxxxx>
Cc: Borislav Petkov <bp@xxxxxxxxx>
Cc: Catalin Marinas <catalin.marinas@xxxxxxx>
Cc: Leif Lindholm <leif.lindholm@xxxxxxxxxx>
Cc: Mark Rutland <mark.rutland@xxxxxxx>
Cc: Peter Jones <pjones@xxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Sai Praneeth Prakhya <sai.praneeth.prakhya@xxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Will Deacon <will.deacon@xxxxxxx>
Cc: linux-efi@xxxxxxxxxxxxxxx
Link: http://lkml.kernel.org/r/1461614832-17633-15-git-send-email-matt@xxxxxxxxxxxxxxxxxxx
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
---
 arch/arm64/include/asm/efi.h       |  2 ++
 drivers/firmware/efi/arm-init.c    |  1 +
 drivers/firmware/efi/arm-runtime.c | 10 ++++++++--
 3 files changed, 11 insertions(+), 2 deletions(-)

diff --git a/arch/arm64/include/asm/efi.h b/arch/arm64/include/asm/efi.h
index 8e88a69..4dafc89 100644
--- a/arch/arm64/include/asm/efi.h
+++ b/arch/arm64/include/asm/efi.h
@@ -14,6 +14,8 @@ extern void efi_init(void);
 
 int efi_create_mapping(struct mm_struct *mm, efi_memory_desc_t *md);
 
+#define efi_set_mapping_permissions	efi_create_mapping
+
 #define efi_call_virt(f, ...)						\
 ({									\
 	efi_##f##_t *__f;						\
diff --git a/drivers/firmware/efi/arm-init.c b/drivers/firmware/efi/arm-init.c
index a84dddb..909d974 100644
--- a/drivers/firmware/efi/arm-init.c
+++ b/drivers/firmware/efi/arm-init.c
@@ -206,6 +206,7 @@ void __init efi_init(void)
 		return;
 
 	reserve_regions();
+	efi_memattr_init();
 	early_memunmap(efi.memmap.map, params.mmap_size);
 
 	if (IS_ENABLED(CONFIG_ARM)) {
diff --git a/drivers/firmware/efi/arm-runtime.c b/drivers/firmware/efi/arm-runtime.c
index 19283de..17ccf0a 100644
--- a/drivers/firmware/efi/arm-runtime.c
+++ b/drivers/firmware/efi/arm-runtime.c
@@ -77,9 +77,15 @@ static bool __init efi_virtmap_init(void)
 			systab_found = true;
 		}
 	}
-	if (!systab_found)
+	if (!systab_found) {
 		pr_err("No virtual mapping found for the UEFI System Table\n");
-	return systab_found;
+		return false;
+	}
+
+	if (efi_memattr_apply_permissions(&efi_mm, efi_set_mapping_permissions))
+		return false;
+
+	return true;
 }
 
 /*