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-rw-r--r--arch/x86/vdso/vdso32/syscall.S69
1 files changed, 69 insertions, 0 deletions
diff --git a/arch/x86/vdso/vdso32/syscall.S b/arch/x86/vdso/vdso32/syscall.S
new file mode 100644
index 00000000000..333bfb552c8
--- /dev/null
+++ b/arch/x86/vdso/vdso32/syscall.S
@@ -0,0 +1,69 @@
1/*
2 * Code for the vsyscall page. This version uses the syscall instruction.
3 */
4
5#include <asm/asm-offsets.h>
6#include <asm/segment.h>
7
8 .text
9 .globl __kernel_vsyscall
10 .type __kernel_vsyscall,@function
11__kernel_vsyscall:
12.LSTART_vsyscall:
13 push %ebp
14.Lpush_ebp:
15 movl %ecx, %ebp
16 syscall
17 movl $__USER32_DS, %ecx
18 movl %ecx, %ss
19 movl %ebp, %ecx
20 popl %ebp
21.Lpop_ebp:
22 ret
23.LEND_vsyscall:
24 .size __kernel_vsyscall,.-.LSTART_vsyscall
25
26 .section .eh_frame,"a",@progbits
27.LSTARTFRAME:
28 .long .LENDCIE-.LSTARTCIE
29.LSTARTCIE:
30 .long 0 /* CIE ID */
31 .byte 1 /* Version number */
32 .string "zR" /* NUL-terminated augmentation string */
33 .uleb128 1 /* Code alignment factor */
34 .sleb128 -4 /* Data alignment factor */
35 .byte 8 /* Return address register column */
36 .uleb128 1 /* Augmentation value length */
37 .byte 0x1b /* DW_EH_PE_pcrel|DW_EH_PE_sdata4. */
38 .byte 0x0c /* DW_CFA_def_cfa */
39 .uleb128 4
40 .uleb128 4
41 .byte 0x88 /* DW_CFA_offset, column 0x8 */
42 .uleb128 1
43 .align 4
44.LENDCIE:
45
46 .long .LENDFDE1-.LSTARTFDE1 /* Length FDE */
47.LSTARTFDE1:
48 .long .LSTARTFDE1-.LSTARTFRAME /* CIE pointer */
49 .long .LSTART_vsyscall-. /* PC-relative start address */
50 .long .LEND_vsyscall-.LSTART_vsyscall
51 .uleb128 0 /* Augmentation length */
52 /* What follows are the instructions for the table generation.
53 We have to record all changes of the stack pointer. */
54 .byte 0x40 + .Lpush_ebp-.LSTART_vsyscall /* DW_CFA_advance_loc */
55 .byte 0x0e /* DW_CFA_def_cfa_offset */
56 .uleb128 8
57 .byte 0x85, 0x02 /* DW_CFA_offset %ebp -8 */
58 .byte 0x40 + .Lpop_ebp-.Lpush_ebp /* DW_CFA_advance_loc */
59 .byte 0xc5 /* DW_CFA_restore %ebp */
60 .byte 0x0e /* DW_CFA_def_cfa_offset */
61 .uleb128 4
62 .align 4
63.LENDFDE1:
64
65/*
66 * Get the common code for the sigreturn entry points.
67 */
68#define SYSCALL_ENTER_KERNEL syscall
69#include "sigreturn.S"