1. 根目录:
2. arch
3. x86
4. include
5. asm
6. sigcontext.h

#ifndef _ASM_X86_SIGCONTEXT_H
#define _ASM_X86_SIGCONTEXT_H

#include <uapi/asm/sigcontext.h>

#ifdef __i386__
struct sigcontext {
	unsigned short gs, __gsh;
	unsigned short fs, __fsh;
	unsigned short es, __esh;
	unsigned short ds, __dsh;
	unsigned long di;
	unsigned long si;
	unsigned long bp;
	unsigned long sp;
	unsigned long bx;
	unsigned long dx;
	unsigned long cx;
	unsigned long ax;
	unsigned long trapno;
	unsigned long err;
	unsigned long ip;
	unsigned short cs, __csh;
	unsigned long flags;
	unsigned long sp_at_signal;
	unsigned short ss, __ssh;

	/*
	 * fpstate is really (struct _fpstate *) or (struct _xstate *)
	 * depending on the FP_XSTATE_MAGIC1 encoded in the SW reserved
	 * bytes of (struct _fpstate) and FP_XSTATE_MAGIC2 present at the end
	 * of extended memory layout. See comments at the definition of
	 * (struct _fpx_sw_bytes)
	 */
	void __user *fpstate;		/* zero when no FPU/extended context */
	unsigned long oldmask;
	unsigned long cr2;
};
#else /* __i386__ */
struct sigcontext {
	unsigned long r8;
	unsigned long r9;
	unsigned long r10;
	unsigned long r11;
	unsigned long r12;
	unsigned long r13;
	unsigned long r14;
	unsigned long r15;
	unsigned long di;
	unsigned long si;
	unsigned long bp;
	unsigned long bx;
	unsigned long dx;
	unsigned long ax;
	unsigned long cx;
	unsigned long sp;
	unsigned long ip;
	unsigned long flags;
	unsigned short cs;
	unsigned short __pad2;	/* Was called gs, but was always zero. */
	unsigned short __pad1;	/* Was called fs, but was always zero. */
	unsigned short ss;
	unsigned long err;
	unsigned long trapno;
	unsigned long oldmask;
	unsigned long cr2;

	/*
	 * fpstate is really (struct _fpstate *) or (struct _xstate *)
	 * depending on the FP_XSTATE_MAGIC1 encoded in the SW reserved
	 * bytes of (struct _fpstate) and FP_XSTATE_MAGIC2 present at the end
	 * of extended memory layout. See comments at the definition of
	 * (struct _fpx_sw_bytes)
	 */
	void __user *fpstate;		/* zero when no FPU/extended context */
	unsigned long reserved1[8];
};
#endif /* !__i386__ */
#endif /* _ASM_X86_SIGCONTEXT_H */