[PATCH] arm64: Fix multiple 'asm-operand-widths' warnings
Matthias Kaehlcke
mka at chromium.org
Mon May 1 14:26:22 PDT 2017
clang raises 'asm-operand-widths' warnings in inline assembly code when
the size of an operand is < 64 bits and the operand width is unspecified.
Most warnings are raised in macros, i.e. the datatype of the operand may
vary. Forcing the use of an x register through the 'x' operand modifier
would silence the warning however it involves the risk that for operands
< 64 bits 'unused' bits may be assigned to 64-bit values (more details at
http://lists.infradead.org/pipermail/linux-arm-kernel/2017-April/503816.html).
Instead we cast the operand to 64 bits, which also forces the use of a
x register, but without the unexpected behavior.
In gic_write_bpr1() use write_sysreg_s() to write the register. This
aligns the functions with others in this header and fixes an
'asm-operand-widths' warning.
Signed-off-by: Matthias Kaehlcke <mka at chromium.org>
---
arch/arm64/include/asm/arch_gicv3.h | 2 +-
arch/arm64/include/asm/barrier.h | 2 +-
arch/arm64/include/asm/uaccess.h | 2 +-
arch/arm64/kernel/armv8_deprecated.c | 2 +-
4 files changed, 4 insertions(+), 4 deletions(-)
diff --git a/arch/arm64/include/asm/arch_gicv3.h b/arch/arm64/include/asm/arch_gicv3.h
index f37e3a21f6e7..9092d612d8c2 100644
--- a/arch/arm64/include/asm/arch_gicv3.h
+++ b/arch/arm64/include/asm/arch_gicv3.h
@@ -166,7 +166,7 @@ static inline void gic_write_sre(u32 val)
static inline void gic_write_bpr1(u32 val)
{
- asm volatile("msr_s " __stringify(ICC_BPR1_EL1) ", %0" : : "r" (val));
+ write_sysreg_s(val, ICC_BPR1_EL1);
}
#define gic_read_typer(c) readq_relaxed(c)
diff --git a/arch/arm64/include/asm/barrier.h b/arch/arm64/include/asm/barrier.h
index 4e0497f581a0..1248401b07ab 100644
--- a/arch/arm64/include/asm/barrier.h
+++ b/arch/arm64/include/asm/barrier.h
@@ -60,7 +60,7 @@ do { \
break; \
case 8: \
asm volatile ("stlr %1, %0" \
- : "=Q" (*p) : "r" (v) : "memory"); \
+ : "=Q" (*p) : "r" ((__u64)v) : "memory"); \
break; \
} \
} while (0)
diff --git a/arch/arm64/include/asm/uaccess.h b/arch/arm64/include/asm/uaccess.h
index 5308d696311b..7db143689694 100644
--- a/arch/arm64/include/asm/uaccess.h
+++ b/arch/arm64/include/asm/uaccess.h
@@ -302,7 +302,7 @@ do { \
" .previous\n" \
_ASM_EXTABLE(1b, 3b) \
: "+r" (err) \
- : "r" (x), "r" (addr), "i" (-EFAULT))
+ : "r" ((__u64)x), "r" (addr), "i" (-EFAULT))
#define __put_user_err(x, ptr, err) \
do { \
diff --git a/arch/arm64/kernel/armv8_deprecated.c b/arch/arm64/kernel/armv8_deprecated.c
index 657977e77ec8..79b9fef48b14 100644
--- a/arch/arm64/kernel/armv8_deprecated.c
+++ b/arch/arm64/kernel/armv8_deprecated.c
@@ -306,7 +306,7 @@ do { \
_ASM_EXTABLE(0b, 4b) \
_ASM_EXTABLE(1b, 4b) \
: "=&r" (res), "+r" (data), "=&r" (temp), "=&r" (temp2) \
- : "r" (addr), "i" (-EAGAIN), "i" (-EFAULT), \
+ : "r" ((__u64)addr), "i" (-EAGAIN), "i" (-EFAULT), \
"i" (__SWP_LL_SC_LOOPS) \
: "memory"); \
uaccess_disable(); \
--
2.13.0.rc0.306.g87b477812d-goog
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