[PATCH 4.4 38/75] arm/arm64: smccc-1.1: Make return values unsigned long

From: Greg Kroah-Hartman
Date: Fri Nov 08 2019 - 13:54:34 EST


From: Marc Zyngier <marc.zyngier@xxxxxxx>

[ Upstream commit 1d8f574708a3fb6f18c85486d0c5217df893c0cf ]

An unfortunate consequence of having a strong typing for the input
values to the SMC call is that it also affects the type of the
return values, limiting r0 to 32 bits and r{1,2,3} to whatever
was passed as an input.

Let's turn everything into "unsigned long", which satisfies the
requirements of both architectures, and allows for the full
range of return values.

Reported-by: Julien Grall <julien.grall@xxxxxxx>
Signed-off-by: Marc Zyngier <marc.zyngier@xxxxxxx>
Signed-off-by: Will Deacon <will.deacon@xxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Ard Biesheuvel <ardb@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
include/linux/arm-smccc.h | 20 ++++++++++----------
1 file changed, 10 insertions(+), 10 deletions(-)

--- a/include/linux/arm-smccc.h
+++ b/include/linux/arm-smccc.h
@@ -167,31 +167,31 @@ asmlinkage void arm_smccc_hvc(unsigned l

#define __declare_arg_0(a0, res) \
struct arm_smccc_res *___res = res; \
- register u32 r0 asm("r0") = a0; \
+ register unsigned long r0 asm("r0") = (u32)a0; \
register unsigned long r1 asm("r1"); \
register unsigned long r2 asm("r2"); \
register unsigned long r3 asm("r3")

#define __declare_arg_1(a0, a1, res) \
struct arm_smccc_res *___res = res; \
- register u32 r0 asm("r0") = a0; \
- register typeof(a1) r1 asm("r1") = a1; \
+ register unsigned long r0 asm("r0") = (u32)a0; \
+ register unsigned long r1 asm("r1") = a1; \
register unsigned long r2 asm("r2"); \
register unsigned long r3 asm("r3")

#define __declare_arg_2(a0, a1, a2, res) \
struct arm_smccc_res *___res = res; \
- register u32 r0 asm("r0") = a0; \
- register typeof(a1) r1 asm("r1") = a1; \
- register typeof(a2) r2 asm("r2") = a2; \
+ register unsigned long r0 asm("r0") = (u32)a0; \
+ register unsigned long r1 asm("r1") = a1; \
+ register unsigned long r2 asm("r2") = a2; \
register unsigned long r3 asm("r3")

#define __declare_arg_3(a0, a1, a2, a3, res) \
struct arm_smccc_res *___res = res; \
- register u32 r0 asm("r0") = a0; \
- register typeof(a1) r1 asm("r1") = a1; \
- register typeof(a2) r2 asm("r2") = a2; \
- register typeof(a3) r3 asm("r3") = a3
+ register unsigned long r0 asm("r0") = (u32)a0; \
+ register unsigned long r1 asm("r1") = a1; \
+ register unsigned long r2 asm("r2") = a2; \
+ register unsigned long r3 asm("r3") = a3

#define __declare_arg_4(a0, a1, a2, a3, a4, res) \
__declare_arg_3(a0, a1, a2, a3, res); \