diff options
Diffstat (limited to 'arch/x86/kernel/vsyscall-sysenter_32.S')
| -rw-r--r-- | arch/x86/kernel/vsyscall-sysenter_32.S | 122 |
1 files changed, 0 insertions, 122 deletions
diff --git a/arch/x86/kernel/vsyscall-sysenter_32.S b/arch/x86/kernel/vsyscall-sysenter_32.S deleted file mode 100644 index ed879bf42995..000000000000 --- a/arch/x86/kernel/vsyscall-sysenter_32.S +++ /dev/null @@ -1,122 +0,0 @@ -/* - * Code for the vsyscall page. This version uses the sysenter instruction. - * - * NOTE: - * 1) __kernel_vsyscall _must_ be first in this page. - * 2) there are alignment constraints on this stub, see vsyscall-sigreturn.S - * for details. - */ - -/* - * The caller puts arg2 in %ecx, which gets pushed. The kernel will use - * %ecx itself for arg2. The pushing is because the sysexit instruction - * (found in entry.S) requires that we clobber %ecx with the desired %esp. - * User code might expect that %ecx is unclobbered though, as it would be - * for returning via the iret instruction, so we must push and pop. - * - * The caller puts arg3 in %edx, which the sysexit instruction requires - * for %eip. Thus, exactly as for arg2, we must push and pop. - * - * Arg6 is different. The caller puts arg6 in %ebp. Since the sysenter - * instruction clobbers %esp, the user's %esp won't even survive entry - * into the kernel. We store %esp in %ebp. Code in entry.S must fetch - * arg6 from the stack. - * - * You can not use this vsyscall for the clone() syscall because the - * three dwords on the parent stack do not get copied to the child. - */ - .text - .globl __kernel_vsyscall - .type __kernel_vsyscall,@function -__kernel_vsyscall: -.LSTART_vsyscall: - push %ecx -.Lpush_ecx: - push %edx -.Lpush_edx: - push %ebp -.Lenter_kernel: - movl %esp,%ebp - sysenter - - /* 7: align return point with nop's to make disassembly easier */ - .space 7,0x90 - - /* 14: System call restart point is here! (SYSENTER_RETURN-2) */ - jmp .Lenter_kernel - /* 16: System call normal return point is here! */ - .globl SYSENTER_RETURN /* Symbol used by sysenter.c */ -SYSENTER_RETURN: - pop %ebp -.Lpop_ebp: - pop %edx -.Lpop_edx: - pop %ecx -.Lpop_ecx: - ret -.LEND_vsyscall: - .size __kernel_vsyscall,.-.LSTART_vsyscall - .previous - - .section .eh_frame,"a",@progbits -.LSTARTFRAMEDLSI: - .long .LENDCIEDLSI-.LSTARTCIEDLSI -.LSTARTCIEDLSI: - .long 0 /* CIE ID */ - .byte 1 /* Version number */ - .string "zR" /* NUL-terminated augmentation string */ - .uleb128 1 /* Code alignment factor */ - .sleb128 -4 /* Data alignment factor */ - .byte 8 /* Return address register column */ - .uleb128 1 /* Augmentation value length */ - .byte 0x1b /* DW_EH_PE_pcrel|DW_EH_PE_sdata4. */ - .byte 0x0c /* DW_CFA_def_cfa */ - .uleb128 4 - .uleb128 4 - .byte 0x88 /* DW_CFA_offset, column 0x8 */ - .uleb128 1 - .align 4 -.LENDCIEDLSI: - .long .LENDFDEDLSI-.LSTARTFDEDLSI /* Length FDE */ -.LSTARTFDEDLSI: - .long .LSTARTFDEDLSI-.LSTARTFRAMEDLSI /* CIE pointer */ - .long .LSTART_vsyscall-. /* PC-relative start address */ - .long .LEND_vsyscall-.LSTART_vsyscall - .uleb128 0 - /* What follows are the instructions for the table generation. - We have to record all changes of the stack pointer. */ - .byte 0x04 /* DW_CFA_advance_loc4 */ - .long .Lpush_ecx-.LSTART_vsyscall - .byte 0x0e /* DW_CFA_def_cfa_offset */ - .byte 0x08 /* RA at offset 8 now */ - .byte 0x04 /* DW_CFA_advance_loc4 */ - .long .Lpush_edx-.Lpush_ecx - .byte 0x0e /* DW_CFA_def_cfa_offset */ - .byte 0x0c /* RA at offset 12 now */ - .byte 0x04 /* DW_CFA_advance_loc4 */ - .long .Lenter_kernel-.Lpush_edx - .byte 0x0e /* DW_CFA_def_cfa_offset */ - .byte 0x10 /* RA at offset 16 now */ - .byte 0x85, 0x04 /* DW_CFA_offset %ebp -16 */ - /* Finally the epilogue. */ - .byte 0x04 /* DW_CFA_advance_loc4 */ - .long .Lpop_ebp-.Lenter_kernel - .byte 0x0e /* DW_CFA_def_cfa_offset */ - .byte 0x0c /* RA at offset 12 now */ - .byte 0xc5 /* DW_CFA_restore %ebp */ - .byte 0x04 /* DW_CFA_advance_loc4 */ - .long .Lpop_edx-.Lpop_ebp - .byte 0x0e /* DW_CFA_def_cfa_offset */ - .byte 0x08 /* RA at offset 8 now */ - .byte 0x04 /* DW_CFA_advance_loc4 */ - .long .Lpop_ecx-.Lpop_edx - .byte 0x0e /* DW_CFA_def_cfa_offset */ - .byte 0x04 /* RA at offset 4 now */ - .align 4 -.LENDFDEDLSI: - .previous - -/* - * Get the common code for the sigreturn entry points. - */ -#include "vsyscall-sigreturn_32.S" |