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/* SPDX-License-Identifier: GPL-2.0-only */
/*
* purgatory: setup code
*
* Copyright (C) 2003,2004 Eric Biederman (ebiederm@xmission.com)
* Copyright (C) 2014 Red Hat Inc.
*
* This code has been taken from kexec-tools.
*/
#include <linux/linkage.h>
#include <asm/purgatory.h>
.text
.balign 16
.code64
SYM_CODE_START(purgatory_start)
/* Load a gdt so I know what the segment registers are */
lgdt gdt(%rip)
/* load the data segments */
movl $0x18, %eax /* data segment */
movl %eax, %ds
movl %eax, %es
movl %eax, %ss
movl %eax, %fs
movl %eax, %gs
/* Setup a stack */
leaq lstack_end(%rip), %rsp
/* Call the C code */
call purgatory
jmp entry64
SYM_CODE_END(purgatory_start)
.section ".rodata"
.balign 16
SYM_DATA_START_LOCAL(gdt)
/* 0x00 unusable segment
* 0x08 unused
* so use them as the gdt ptr
*/
.word gdt_end - gdt - 1
.quad gdt
.word 0, 0, 0
/* 0x10 4GB flat code segment */
.word 0xFFFF, 0x0000, 0x9A00, 0x00AF
/* 0x18 4GB flat data segment */
.word 0xFFFF, 0x0000, 0x9200, 0x00CF
SYM_DATA_END_LABEL(gdt, SYM_L_LOCAL, gdt_end)
.bss
.balign 4096
SYM_DATA_START_LOCAL(lstack)
.skip 4096
SYM_DATA_END_LABEL(lstack, SYM_L_LOCAL, lstack_end)
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