[PATCH 39/40] x86/efi: Enable runtime call flag checking

From: Matt Fleming
Date: Mon Apr 25 2016 - 16:08:49 EST


From: Mark Rutland <mark.rutland@xxxxxxx>

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: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: linux-efi@xxxxxxxxxxxxxxx
Cc: linux-kernel@xxxxxxxxxxxxxxx
Cc: Catalin Marinas <catalin.marinas@xxxxxxx>
Cc: Leif Lindholm <leif.lindholm@xxxxxxxxxx>
Cc: Russell King <linux@xxxxxxxxxxxxxxxx>
Cc: Will Deacon <will.deacon@xxxxxxx>
Cc: Greg KH <gregkh@xxxxxxxxxxxxxxxxxxx>
Cc: James Bottomley <James.Bottomley@xxxxxxxxxxxxxxxxxxxxx>
Cc: David Howells <dhowells@xxxxxxxxxx>
Cc: Harald Hoyer harald@xxxxxxxxxx
Cc: Kweh Hock Leong <hock.leong.kweh@xxxxxxxxx>
Cc: Christoph Hellwig <hch@xxxxxx>
Cc: Hannes Reinecke <hare@xxxxxxx>
Cc: Raphael Hertzog <hertzog@xxxxxxxxxx>
Cc: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
Cc: David Herrmann <dh.herrmann@xxxxxxxxx>
Cc: Darren Hart <dvhart@xxxxxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Peter Jones <pjones@xxxxxxxxxx>
Signed-off-by: Matt Fleming <matt@xxxxxxxxxxxxxxxxxxx>
---
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 fb085ce00bd2..78d1e7467eae 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 *, ...);

--
2.7.3