diff options
Diffstat (limited to 'arch/arm64/include/uapi/asm/sigcontext.h')
| -rw-r--r-- | arch/arm64/include/uapi/asm/sigcontext.h | 14 |
1 files changed, 14 insertions, 0 deletions
diff --git a/arch/arm64/include/uapi/asm/sigcontext.h b/arch/arm64/include/uapi/asm/sigcontext.h index 5f3c0cec5af9..3d448a0bb225 100644 --- a/arch/arm64/include/uapi/asm/sigcontext.h +++ b/arch/arm64/include/uapi/asm/sigcontext.h @@ -77,6 +77,15 @@ struct fpsimd_context { __uint128_t vregs[32]; }; +/* + * Note: similarly to all other integer fields, each V-register is stored in an + * endianness-dependent format, with the byte at offset i from the start of the + * in-memory representation of the register value containing + * + * bits [(7 + 8 * i) : (8 * i)] of the register on little-endian hosts; or + * bits [(127 - 8 * i) : (120 - 8 * i)] on big-endian hosts. + */ + /* ESR_EL1 context */ #define ESR_MAGIC 0x45535201 @@ -204,6 +213,11 @@ struct sve_context { * FFR uint16_t[vq] first-fault status register * * Additional data might be appended in the future. + * + * Unlike vregs[] in fpsimd_context, each SVE scalable register (Z-, P- or FFR) + * is encoded in memory in an endianness-invariant format, with the byte at + * offset i from the start of the in-memory representation containing bits + * [(7 + 8 * i) : (8 * i)] of the register value. */ #define SVE_SIG_ZREG_SIZE(vq) __SVE_ZREG_SIZE(vq) |