[PATCHv3 4/5] x86/efi: enable runtime call flag checking

From: Mark Rutland
Date: Mon Apr 25 2016 - 09:47:10 EST


Define ARCH_EFI_IRQ_FLAGS_MASK for x86, which will enable the generic
runtime wrapper code to detect when firmware erroneously modifies flags
over a runtime services function call.

For x86 (both 32-bit and 64-bit), we only need check the interrupt flag.

Signed-off-by: Mark Rutland <mark.rutland@xxxxxxx>
Cc: Ard Biesheuvel <ard.biesheuvel@xxxxxxxxxx>
Cc: H. Peter Anvin <hpa@xxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: Matt Fleming <matt@xxxxxxxxxxxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: linux-efi@xxxxxxxxxxxxxxx
Cc: linux-kernel@xxxxxxxxxxxxxxx
---
arch/x86/include/asm/efi.h | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/arch/x86/include/asm/efi.h b/arch/x86/include/asm/efi.h
index 34bd38b..c6d8ad1 100644
--- a/arch/x86/include/asm/efi.h
+++ b/arch/x86/include/asm/efi.h
@@ -3,6 +3,7 @@

#include <asm/fpu/api.h>
#include <asm/pgtable.h>
+#include <asm/processor-flags.h>
#include <asm/tlb.h>

/*
@@ -28,8 +29,9 @@

#define MAX_CMDLINE_ADDRESS UINT_MAX

-#ifdef CONFIG_X86_32
+#define ARCH_EFI_IRQ_FLAGS_MASK X86_EFLAGS_IF

+#ifdef CONFIG_X86_32

extern unsigned long asmlinkage efi_call_phys(void *, ...);

--
1.9.1