diff options
Diffstat (limited to 'arch/arm64/include/asm/assembler.h')
| -rw-r--r-- | arch/arm64/include/asm/assembler.h | 50 |
1 files changed, 50 insertions, 0 deletions
diff --git a/arch/arm64/include/asm/assembler.h b/arch/arm64/include/asm/assembler.h index 0bff325117b4..54d181177656 100644 --- a/arch/arm64/include/asm/assembler.h +++ b/arch/arm64/include/asm/assembler.h @@ -736,4 +736,54 @@ USER(\label, ic ivau, \tmp2) // invalidate I line PoU .Lyield_out_\@ : .endm +/* + * This macro emits a program property note section identifying + * architecture features which require special handling, mainly for + * use in assembly files included in the VDSO. + */ + +#define NT_GNU_PROPERTY_TYPE_0 5 +#define GNU_PROPERTY_AARCH64_FEATURE_1_AND 0xc0000000 + +#define GNU_PROPERTY_AARCH64_FEATURE_1_BTI (1U << 0) +#define GNU_PROPERTY_AARCH64_FEATURE_1_PAC (1U << 1) + +#ifdef CONFIG_ARM64_BTI_KERNEL +#define GNU_PROPERTY_AARCH64_FEATURE_1_DEFAULT \ + ((GNU_PROPERTY_AARCH64_FEATURE_1_BTI | \ + GNU_PROPERTY_AARCH64_FEATURE_1_PAC)) +#endif + +#ifdef GNU_PROPERTY_AARCH64_FEATURE_1_DEFAULT +.macro emit_aarch64_feature_1_and, feat=GNU_PROPERTY_AARCH64_FEATURE_1_DEFAULT + .pushsection .note.gnu.property, "a" + .align 3 + .long 2f - 1f + .long 6f - 3f + .long NT_GNU_PROPERTY_TYPE_0 +1: .string "GNU" +2: + .align 3 +3: .long GNU_PROPERTY_AARCH64_FEATURE_1_AND + .long 5f - 4f +4: + /* + * This is described with an array of char in the Linux API + * spec but the text and all other usage (including binutils, + * clang and GCC) treat this as a 32 bit value so no swizzling + * is required for big endian. + */ + .long \feat +5: + .align 3 +6: + .popsection +.endm + +#else +.macro emit_aarch64_feature_1_and, feat=0 +.endm + +#endif /* GNU_PROPERTY_AARCH64_FEATURE_1_DEFAULT */ + #endif /* __ASM_ASSEMBLER_H */ |