[PATCH v3 15/18] arm/arm64: smccc: Make function identifiers an unsigned quantity

Marc Zyngier marc.zyngier at arm.com
Thu Feb 1 03:46:54 PST 2018


Function identifiers are a 32bit, unsigned quantity. But we never
tell so to the compiler, resulting in the following:

 4ac:   b26187e0        mov     x0, #0xffffffff80000001

We thus rely on the firmware narrowing it for us, which is not
always a reasonable expectation.

Cc: stable at vger.kernel.org
Reported-by: Ard Biesheuvel <ard.biesheuvel at linaro.org>
Acked-by: Ard Biesheuvel <ard.biesheuvel at linaro.org>
Tested-by: Ard Biesheuvel <ard.biesheuvel at linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier at arm.com>
---
 include/linux/arm-smccc.h | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/include/linux/arm-smccc.h b/include/linux/arm-smccc.h
index e1ef944ef1da..dd44d8458c04 100644
--- a/include/linux/arm-smccc.h
+++ b/include/linux/arm-smccc.h
@@ -14,14 +14,16 @@
 #ifndef __LINUX_ARM_SMCCC_H
 #define __LINUX_ARM_SMCCC_H
 
+#include <uapi/linux/const.h>
+
 /*
  * This file provides common defines for ARM SMC Calling Convention as
  * specified in
  * http://infocenter.arm.com/help/topic/com.arm.doc.den0028a/index.html
  */
 
-#define ARM_SMCCC_STD_CALL		0
-#define ARM_SMCCC_FAST_CALL		1
+#define ARM_SMCCC_STD_CALL	        _AC(0,U)
+#define ARM_SMCCC_FAST_CALL	        _AC(1,U)
 #define ARM_SMCCC_TYPE_SHIFT		31
 
 #define ARM_SMCCC_SMC_32		0
-- 
2.14.2




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