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/* arch/i386/gdt.c */
.set SEG_r0code, 1
.set SEG_r3code, 3
.set SEG_r3data, 4
.set IA32_SYSENTER_CS, 0x174
.section .text
.global sysexit
.type sysexit, @function
sysexit:
pop %ecx
pop %edx
mov $(SEG_r3data << 3 | 3), %ax
mov %ax, %ds
mov %ax, %es
mov %ax, %fs
mov %ax, %gs
// enable paging
mov %cr0, %eax
or $0x80000000, %eax
mov %eax, %cr0
sysexit
.global sysenter_setup
.type sysenter_setup, @function
sysenter_setup:
xor %edx, %edx
mov $(SEG_r0code << 3), %eax
mov $IA32_SYSENTER_CS, %ecx
wrmsr
ret
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