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5234f5eb04
This is the x86_64 implementation of machine kexec. 32bit compatibility support has been implemented, and machine_kexec has been enhanced to not care about the changing internal kernel paget table structures. From: Alexander Nyberg <alexn@dsv.su.se> build fix Signed-off-by: Eric Biederman <ebiederm@xmission.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
144 lines
3.2 KiB
ArmAsm
144 lines
3.2 KiB
ArmAsm
/*
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* relocate_kernel.S - put the kernel image in place to boot
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* Copyright (C) 2002-2005 Eric Biederman <ebiederm@xmission.com>
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*
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* This source code is licensed under the GNU General Public License,
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* Version 2. See the file COPYING for more details.
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*/
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#include <linux/linkage.h>
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/*
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* Must be relocatable PIC code callable as a C function, that once
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* it starts can not use the previous processes stack.
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*/
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.globl relocate_new_kernel
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.code64
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relocate_new_kernel:
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/* %rdi page_list
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* %rsi reboot_code_buffer
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* %rdx start address
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* %rcx page_table
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* %r8 arg5
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* %r9 arg6
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*/
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/* zero out flags, and disable interrupts */
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pushq $0
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popfq
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/* set a new stack at the bottom of our page... */
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lea 4096(%rsi), %rsp
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/* store the parameters back on the stack */
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pushq %rdx /* store the start address */
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/* Set cr0 to a known state:
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* 31 1 == Paging enabled
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* 18 0 == Alignment check disabled
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* 16 0 == Write protect disabled
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* 3 0 == No task switch
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* 2 0 == Don't do FP software emulation.
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* 0 1 == Proctected mode enabled
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*/
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movq %cr0, %rax
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andq $~((1<<18)|(1<<16)|(1<<3)|(1<<2)), %rax
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orl $((1<<31)|(1<<0)), %eax
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movq %rax, %cr0
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/* Set cr4 to a known state:
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* 10 0 == xmm exceptions disabled
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* 9 0 == xmm registers instructions disabled
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* 8 0 == performance monitoring counter disabled
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* 7 0 == page global disabled
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* 6 0 == machine check exceptions disabled
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* 5 1 == physical address extension enabled
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* 4 0 == page size extensions disabled
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* 3 0 == Debug extensions disabled
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* 2 0 == Time stamp disable (disabled)
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* 1 0 == Protected mode virtual interrupts disabled
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* 0 0 == VME disabled
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*/
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movq $((1<<5)), %rax
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movq %rax, %cr4
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jmp 1f
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1:
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/* Switch to the identity mapped page tables,
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* and flush the TLB.
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*/
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movq %rcx, %cr3
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/* Do the copies */
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movq %rdi, %rcx /* Put the page_list in %rcx */
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xorq %rdi, %rdi
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xorq %rsi, %rsi
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jmp 1f
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0: /* top, read another word for the indirection page */
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movq (%rbx), %rcx
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addq $8, %rbx
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1:
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testq $0x1, %rcx /* is it a destination page? */
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jz 2f
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movq %rcx, %rdi
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andq $0xfffffffffffff000, %rdi
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jmp 0b
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2:
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testq $0x2, %rcx /* is it an indirection page? */
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jz 2f
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movq %rcx, %rbx
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andq $0xfffffffffffff000, %rbx
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jmp 0b
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2:
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testq $0x4, %rcx /* is it the done indicator? */
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jz 2f
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jmp 3f
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2:
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testq $0x8, %rcx /* is it the source indicator? */
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jz 0b /* Ignore it otherwise */
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movq %rcx, %rsi /* For ever source page do a copy */
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andq $0xfffffffffffff000, %rsi
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movq $512, %rcx
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rep ; movsq
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jmp 0b
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3:
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/* To be certain of avoiding problems with self-modifying code
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* I need to execute a serializing instruction here.
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* So I flush the TLB by reloading %cr3 here, it's handy,
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* and not processor dependent.
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*/
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movq %cr3, %rax
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movq %rax, %cr3
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/* set all of the registers to known values */
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/* leave %rsp alone */
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xorq %rax, %rax
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xorq %rbx, %rbx
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xorq %rcx, %rcx
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xorq %rdx, %rdx
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xorq %rsi, %rsi
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xorq %rdi, %rdi
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xorq %rbp, %rbp
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xorq %r8, %r8
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xorq %r9, %r9
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xorq %r10, %r9
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xorq %r11, %r11
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xorq %r12, %r12
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xorq %r13, %r13
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xorq %r14, %r14
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xorq %r15, %r15
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ret
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relocate_new_kernel_end:
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.globl relocate_new_kernel_size
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relocate_new_kernel_size:
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.quad relocate_new_kernel_end - relocate_new_kernel
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