Question about entry.S RESTORE_REGS macro

[Ed Reed <ed.reed@xxxxxxxxx>]

I'm looking at the entry / exit routines to the kernel in 
arch/i386/kernel/entry.S, and at the entry conditions for 
ret_from_fork() that is also defined there....

And looking at the assembler macro defined at the top of the file, 
RESTORE_REGS, I'm trying to figure out what the ELF section stuff is 
doing there - have you a clue, or a pointer you give me as to whom to 
ask?  I don't THINK it's relevant to my current efforts, but I'd like to 
understand what's going on.

code:

#define SAVE_ALL \
      cld; \
      pushl %es; \
      pushl %ds; \
      pushl %eax; \
      pushl %ebp; \
      pushl %edi; \
      pushl %esi; \
      pushl %edx; \
      pushl %ecx; \
      pushl %ebx; \
      movl $(__USER_DS), %edx; \
      movl %edx, %ds; \
      movl %edx, %es;

#define RESTORE_INT_REGS \
      popl %ebx;      \
      popl %ecx;      \
      popl %edx;      \
      popl %esi;      \
      popl %edi;      \
      popl %ebp;      \
      popl %eax

#define RESTORE_REGS    \
      RESTORE_INT_REGS; \
1:      popl %ds;       \
2:      popl %es;       \
.section .fixup,"ax";   \
3:      movl $0,(%esp); \
      jmp 1b;         \
4:      movl $0,(%esp); \
      jmp 2b;         \
.previous;              \
.section __ex_table,"a";\
      .align 4;       \
      .long 1b,3b;    \
      .long 2b,4b;    \
.previous


The SAVE_ALL and RESTORE_INT_REGS seem pretty straight forward, but in 
RESTORE_REGS, are the two section entries and labels creating relocation 
entries for the popl %ds and %es instructions?

Newbie question, I suppose, but that's the only think I can see that 
would make sense, and don't know who else to ask.


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