diff options
| author | Sami Tolvanen <samitolvanen@google.com> | 2019-10-31 12:57:05 -0700 |
|---|---|---|
| committer | Will Deacon <will@kernel.org> | 2020-01-16 17:25:10 +0000 |
| commit | e0d5896bd356cd577f9710a02d7a474cdf58426b (patch) | |
| tree | 71b7d809433f946029bb3dd4d27ad17cf552cd4d /arch/arm64/include/asm/lse.h | |
| parent | 46cf053efec6a3a5f343fead837777efe8252a46 (diff) | |
arm64: lse: fix LSE atomics with LLVM's integrated assembler
Unlike gcc, clang considers each inline assembly block to be independent
and therefore, when using the integrated assembler for inline assembly,
any preambles that enable features must be repeated in each block.
This change defines __LSE_PREAMBLE and adds it to each inline assembly
block that has LSE instructions, which allows them to be compiled also
with clang's assembler.
Link: https://github.com/ClangBuiltLinux/linux/issues/671
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
Tested-by: Andrew Murray <andrew.murray@arm.com>
Tested-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Andrew Murray <andrew.murray@arm.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Will Deacon <will@kernel.org>
Diffstat (limited to 'arch/arm64/include/asm/lse.h')
| -rw-r--r-- | arch/arm64/include/asm/lse.h | 6 |
1 files changed, 3 insertions, 3 deletions
diff --git a/arch/arm64/include/asm/lse.h b/arch/arm64/include/asm/lse.h index 80b388278149..73834996c4b6 100644 --- a/arch/arm64/include/asm/lse.h +++ b/arch/arm64/include/asm/lse.h @@ -6,6 +6,8 @@ #if defined(CONFIG_AS_LSE) && defined(CONFIG_ARM64_LSE_ATOMICS) +#define __LSE_PREAMBLE ".arch armv8-a+lse\n" + #include <linux/compiler_types.h> #include <linux/export.h> #include <linux/jump_label.h> @@ -14,8 +16,6 @@ #include <asm/atomic_lse.h> #include <asm/cpucaps.h> -__asm__(".arch_extension lse"); - extern struct static_key_false cpu_hwcap_keys[ARM64_NCAPS]; extern struct static_key_false arm64_const_caps_ready; @@ -34,7 +34,7 @@ static inline bool system_uses_lse_atomics(void) /* In-line patching at runtime */ #define ARM64_LSE_ATOMIC_INSN(llsc, lse) \ - ALTERNATIVE(llsc, lse, ARM64_HAS_LSE_ATOMICS) + ALTERNATIVE(llsc, __LSE_PREAMBLE lse, ARM64_HAS_LSE_ATOMICS) #else /* CONFIG_AS_LSE && CONFIG_ARM64_LSE_ATOMICS */ |