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/*
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* Code for the vsyscall page. This version uses the sysenter instruction.
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*/
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#include <asm/ia32_unistd.h>
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#include <asm/asm-offsets.h>
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.code32
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.text
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.section .text.vsyscall,"ax"
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.globl __kernel_vsyscall
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.type __kernel_vsyscall,@function
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__kernel_vsyscall:
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.LSTART_vsyscall:
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push %ecx
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.Lpush_ecx:
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push %edx
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.Lpush_edx:
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push %ebp
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.Lenter_kernel:
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movl %esp,%ebp
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sysenter
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.space 7,0x90
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jmp .Lenter_kernel
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/* 16: System call normal return point is here! */
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pop %ebp
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.Lpop_ebp:
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pop %edx
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.Lpop_edx:
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pop %ecx
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.Lpop_ecx:
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ret
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.LEND_vsyscall:
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.size __kernel_vsyscall,.-.LSTART_vsyscall
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.section .eh_frame,"a",@progbits
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.LSTARTFRAME:
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.long .LENDCIE-.LSTARTCIE
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.LSTARTCIE:
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.long 0 /* CIE ID */
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.byte 1 /* Version number */
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.string "zR" /* NUL-terminated augmentation string */
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.uleb128 1 /* Code alignment factor */
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.sleb128 -4 /* Data alignment factor */
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.byte 8 /* Return address register column */
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.uleb128 1 /* Augmentation value length */
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.byte 0x1b /* DW_EH_PE_pcrel|DW_EH_PE_sdata4. */
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.byte 0x0c /* DW_CFA_def_cfa */
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.uleb128 4
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.uleb128 4
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.byte 0x88 /* DW_CFA_offset, column 0x8 */
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.uleb128 1
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.align 4
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.LENDCIE:
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.long .LENDFDE1-.LSTARTFDE1 /* Length FDE */
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.LSTARTFDE1:
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.long .LSTARTFDE1-.LSTARTFRAME /* CIE pointer */
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.long .LSTART_vsyscall-. /* PC-relative start address */
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.long .LEND_vsyscall-.LSTART_vsyscall
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.uleb128 0 /* Augmentation length */
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/* What follows are the instructions for the table generation.
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We have to record all changes of the stack pointer. */
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.byte 0x04 /* DW_CFA_advance_loc4 */
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.long .Lpush_ecx-.LSTART_vsyscall
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.byte 0x0e /* DW_CFA_def_cfa_offset */
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.byte 0x08 /* RA at offset 8 now */
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.byte 0x04 /* DW_CFA_advance_loc4 */
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.long .Lpush_edx-.Lpush_ecx
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.byte 0x0e /* DW_CFA_def_cfa_offset */
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.byte 0x0c /* RA at offset 12 now */
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.byte 0x04 /* DW_CFA_advance_loc4 */
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.long .Lenter_kernel-.Lpush_edx
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.byte 0x0e /* DW_CFA_def_cfa_offset */
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.byte 0x10 /* RA at offset 16 now */
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.byte 0x85, 0x04 /* DW_CFA_offset %ebp -16 */
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/* Finally the epilogue. */
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.byte 0x04 /* DW_CFA_advance_loc4 */
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.long .Lpop_ebp-.Lenter_kernel
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.byte 0x0e /* DW_CFA_def_cfa_offset */
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.byte 0x12 /* RA at offset 12 now */
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.byte 0xc5 /* DW_CFA_restore %ebp */
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.byte 0x04 /* DW_CFA_advance_loc4 */
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.long .Lpop_edx-.Lpop_ebp
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.byte 0x0e /* DW_CFA_def_cfa_offset */
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.byte 0x08 /* RA at offset 8 now */
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.byte 0x04 /* DW_CFA_advance_loc4 */
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.long .Lpop_ecx-.Lpop_edx
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.byte 0x0e /* DW_CFA_def_cfa_offset */
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.byte 0x04 /* RA at offset 4 now */
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.align 4
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.LENDFDE1:
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#define SYSCALL_ENTER_KERNEL int $0x80
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#include "vsyscall-sigreturn.S"
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