2 * Code for the vDSO. This version uses the syscall instruction.
4 * First get the common code for the sigreturn entry points.
5 * This must come first.
7 #define SYSCALL_ENTER_KERNEL syscall
10 #include <asm/segment.h>
13 .globl __kernel_vsyscall
14 .type __kernel_vsyscall,@function
22 movl $__USER32_DS, %ecx
29 .size __kernel_vsyscall,.-.LSTART_vsyscall
31 .section .eh_frame,"a",@progbits
33 .long .LENDCIE-.LSTARTCIE
36 .byte 1 /* Version number */
37 .string "zR" /* NUL-terminated augmentation string */
38 .uleb128 1 /* Code alignment factor */
39 .sleb128 -4 /* Data alignment factor */
40 .byte 8 /* Return address register column */
41 .uleb128 1 /* Augmentation value length */
42 .byte 0x1b /* DW_EH_PE_pcrel|DW_EH_PE_sdata4. */
43 .byte 0x0c /* DW_CFA_def_cfa */
46 .byte 0x88 /* DW_CFA_offset, column 0x8 */
51 .long .LENDFDE1-.LSTARTFDE1 /* Length FDE */
53 .long .LSTARTFDE1-.LSTARTFRAME /* CIE pointer */
54 .long .LSTART_vsyscall-. /* PC-relative start address */
55 .long .LEND_vsyscall-.LSTART_vsyscall
56 .uleb128 0 /* Augmentation length */
57 /* What follows are the instructions for the table generation.
58 We have to record all changes of the stack pointer. */
59 .byte 0x40 + .Lpush_ebp-.LSTART_vsyscall /* DW_CFA_advance_loc */
60 .byte 0x0e /* DW_CFA_def_cfa_offset */
62 .byte 0x85, 0x02 /* DW_CFA_offset %ebp -8 */
63 .byte 0x40 + .Lpop_ebp-.Lpush_ebp /* DW_CFA_advance_loc */
64 .byte 0xc5 /* DW_CFA_restore %ebp */
65 .byte 0x0e /* DW_CFA_def_cfa_offset */
72 * Pad out the segment to match the size of the sysenter.S version.
74 VDSO32_vsyscall_eh_frame_size = 0x40
75 .section .data,"aw",@progbits
76 .space VDSO32_vsyscall_eh_frame_size-(.LENDFDE1-.LSTARTFRAME), 0