diff options
Diffstat (limited to 'arch/x86/include/uapi/asm/ptrace-abi.h')
| -rw-r--r-- | arch/x86/include/uapi/asm/ptrace-abi.h | 16 |
1 files changed, 11 insertions, 5 deletions
diff --git a/arch/x86/include/uapi/asm/ptrace-abi.h b/arch/x86/include/uapi/asm/ptrace-abi.h index 7b0a55a88851..580aee3072e0 100644 --- a/arch/x86/include/uapi/asm/ptrace-abi.h +++ b/arch/x86/include/uapi/asm/ptrace-abi.h @@ -25,13 +25,17 @@ #else /* __i386__ */ #if defined(__ASSEMBLY__) || defined(__FRAME_OFFSETS) +/* + * C ABI says these regs are callee-preserved. They aren't saved on kernel entry + * unless syscall needs a complete, fully filled "struct pt_regs". + */ #define R15 0 #define R14 8 #define R13 16 #define R12 24 #define RBP 32 #define RBX 40 -/* arguments: interrupts/non tracing syscalls only save up to here*/ +/* These regs are callee-clobbered. Always saved on kernel entry. */ #define R11 48 #define R10 56 #define R9 64 @@ -41,15 +45,17 @@ #define RDX 96 #define RSI 104 #define RDI 112 -#define ORIG_RAX 120 /* = ERROR */ -/* end of arguments */ -/* cpu exception frame or undefined in case of fast syscall. */ +/* + * On syscall entry, this is syscall#. On CPU exception, this is error code. + * On hw interrupt, it's IRQ number: + */ +#define ORIG_RAX 120 +/* Return frame for iretq */ #define RIP 128 #define CS 136 #define EFLAGS 144 #define RSP 152 #define SS 160 -#define ARGOFFSET R11 #endif /* __ASSEMBLY__ */ /* top of stack page */ |