arch/um/sys-x86_64/stub.S

   1 #include "uml-config.h"
   2
   3         .globl syscall_stub
   4 .section .__syscall_stub, "x"
   5 syscall_stub:
   6         syscall
   7         /* We don't have 64-bit constants, so this constructs the address
   8          * we need.
   9          */
  10         movq    $(UML_CONFIG_STUB_DATA >> 32), %rbx
  11         salq    $32, %rbx
  12         movq    $(UML_CONFIG_STUB_DATA & 0xffffffff), %rcx
  13         or      %rcx, %rbx
  14         movq    %rax, (%rbx)
  15         int3
  16
  17         .globl batch_syscall_stub
  18 batch_syscall_stub:
  19         movq    $(UML_CONFIG_STUB_DATA >> 32), %rbx
  20         salq    $32, %rbx
  21         movq    $(UML_CONFIG_STUB_DATA & 0xffffffff), %rcx
  22         or      %rcx, %rbx
  23         movq    %rbx, %rsp
  24 again:  pop     %rax
  25         cmpq    $0, %rax
  26 jz      done
  27         pop     %rdi
  28         pop     %rsi
  29         pop     %rdx
  30         pop     %r10
  31         pop     %r8
  32         pop     %r9
  33         syscall
  34         mov     %rax, (%rbx)
  35         jmp     again
  36 done:   int3