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| author | Will Deacon <will.deacon@arm.com> | 2018-11-29 16:31:04 +0000 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2019-02-12 19:47:03 +0100 |
| commit | ed0526b271b9455b1db12e3788e5a612e0464ff7 (patch) | |
| tree | b38a517b280b69b9a452071bdeba98597d6b15a6 /arch | |
| parent | 68b4512ca6fcd474a8e144863f03410ed186232b (diff) | |
arm64: io: Ensure value passed to __iormb() is held in a 64-bit register
[ Upstream commit 1b57ec8c75279b873639eb44a215479236f93481 ]
As of commit 6460d3201471 ("arm64: io: Ensure calls to delay routines
are ordered against prior readX()"), MMIO reads smaller than 64 bits
fail to compile under clang because we end up mixing 32-bit and 64-bit
register operands for the same data processing instruction:
./include/asm-generic/io.h:695:9: warning: value size does not match register size specified by the constraint and modifier [-Wasm-operand-widths]
return readb(addr);
^
./arch/arm64/include/asm/io.h:147:58: note: expanded from macro 'readb'
^
./include/asm-generic/io.h:695:9: note: use constraint modifier "w"
./arch/arm64/include/asm/io.h:147:50: note: expanded from macro 'readb'
^
./arch/arm64/include/asm/io.h:118:24: note: expanded from macro '__iormb'
asm volatile("eor %0, %1, %1\n" \
^
Fix the build by casting the macro argument to 'unsigned long' when used
as an input to the inline asm.
Reported-by: Nick Desaulniers <nick.desaulniers@gmail.com>
Reported-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/arm64/include/asm/io.h | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/arch/arm64/include/asm/io.h b/arch/arm64/include/asm/io.h index b2bc7dbc1fa6..49bb9a020a09 100644 --- a/arch/arm64/include/asm/io.h +++ b/arch/arm64/include/asm/io.h @@ -119,7 +119,8 @@ static inline u64 __raw_readq(const volatile void __iomem *addr) */ \ asm volatile("eor %0, %1, %1\n" \ "cbnz %0, ." \ - : "=r" (tmp) : "r" (v) : "memory"); \ + : "=r" (tmp) : "r" ((unsigned long)(v)) \ + : "memory"); \ }) #define __iowmb() wmb() |