1/* SPDX-License-Identifier: GPL-2.0-only */ 2/* 3 * Hibernation support for x86-64 4 * 5 * Copyright 2007 Rafael J. Wysocki <rjw@sisk.pl> 6 * Copyright 2005 Andi Kleen <ak@suse.de> 7 * Copyright 2004 Pavel Machek <pavel@suse.cz> 8 * 9 * swsusp_arch_resume must not use any stack or any nonlocal variables while 10 * copying pages: 11 * 12 * Its rewriting one kernel image with another. What is stack in "old" 13 * image could very well be data page in "new" image, and overwriting 14 * your own stack under you is bad idea. 15 */ 16 17 .text 18#include <linux/linkage.h> 19#include <asm/segment.h> 20#include <asm/page_types.h> 21#include <asm/asm-offsets.h> 22#include <asm/processor-flags.h> 23#include <asm/frame.h> 24#include <asm/nospec-branch.h> 25 26 /* code below belongs to the image kernel */ 27 .align PAGE_SIZE 28SYM_FUNC_START(restore_registers) 29 /* go back to the original page tables */ 30 movq %r9, %cr3 31 32 /* Flush TLB, including "global" things (vmalloc) */ 33 movq mmu_cr4_features(%rip), %rax 34 movq %rax, %rdx 35 andq $~(X86_CR4_PGE), %rdx 36 movq %rdx, %cr4; # turn off PGE 37 movq %cr3, %rcx; # flush TLB 38 movq %rcx, %cr3 39 movq %rax, %cr4; # turn PGE back on 40 41 /* We don't restore %rax, it must be 0 anyway */ 42 movq $saved_context, %rax 43 movq pt_regs_sp(%rax), %rsp 44 movq pt_regs_bp(%rax), %rbp 45 movq pt_regs_si(%rax), %rsi 46 movq pt_regs_di(%rax), %rdi 47 movq pt_regs_bx(%rax), %rbx 48 movq pt_regs_cx(%rax), %rcx 49 movq pt_regs_dx(%rax), %rdx 50 movq pt_regs_r8(%rax), %r8 51 movq pt_regs_r9(%rax), %r9 52 movq pt_regs_r10(%rax), %r10 53 movq pt_regs_r11(%rax), %r11 54 movq pt_regs_r12(%rax), %r12 55 movq pt_regs_r13(%rax), %r13 56 movq pt_regs_r14(%rax), %r14 57 movq pt_regs_r15(%rax), %r15 58 pushq pt_regs_flags(%rax) 59 popfq 60 61 /* Saved in save_processor_state. */ 62 lgdt saved_context_gdt_desc(%rax) 63 64 xorl %eax, %eax 65 66 /* tell the hibernation core that we've just restored the memory */ 67 movq %rax, in_suspend(%rip) 68 69 ret 70SYM_FUNC_END(restore_registers) 71 72SYM_FUNC_START(swsusp_arch_suspend) 73 movq $saved_context, %rax 74 movq %rsp, pt_regs_sp(%rax) 75 movq %rbp, pt_regs_bp(%rax) 76 movq %rsi, pt_regs_si(%rax) 77 movq %rdi, pt_regs_di(%rax) 78 movq %rbx, pt_regs_bx(%rax) 79 movq %rcx, pt_regs_cx(%rax) 80 movq %rdx, pt_regs_dx(%rax) 81 movq %r8, pt_regs_r8(%rax) 82 movq %r9, pt_regs_r9(%rax) 83 movq %r10, pt_regs_r10(%rax) 84 movq %r11, pt_regs_r11(%rax) 85 movq %r12, pt_regs_r12(%rax) 86 movq %r13, pt_regs_r13(%rax) 87 movq %r14, pt_regs_r14(%rax) 88 movq %r15, pt_regs_r15(%rax) 89 pushfq 90 popq pt_regs_flags(%rax) 91 92 /* save cr3 */ 93 movq %cr3, %rax 94 movq %rax, restore_cr3(%rip) 95 96 FRAME_BEGIN 97 call swsusp_save 98 FRAME_END 99 ret 100SYM_FUNC_END(swsusp_arch_suspend) 101 102SYM_FUNC_START(restore_image) 103 /* prepare to jump to the image kernel */ 104 movq restore_jump_address(%rip), %r8 105 movq restore_cr3(%rip), %r9 106 107 /* prepare to switch to temporary page tables */ 108 movq temp_pgt(%rip), %rax 109 movq mmu_cr4_features(%rip), %rbx 110 111 /* prepare to copy image data to their original locations */ 112 movq restore_pblist(%rip), %rdx 113 114 /* jump to relocated restore code */ 115 movq relocated_restore_code(%rip), %rcx 116 ANNOTATE_RETPOLINE_SAFE 117 jmpq *%rcx 118SYM_FUNC_END(restore_image) 119 120 /* code below has been relocated to a safe page */ 121SYM_FUNC_START(core_restore_code) 122 /* switch to temporary page tables */ 123 movq %rax, %cr3 124 /* flush TLB */ 125 movq %rbx, %rcx 126 andq $~(X86_CR4_PGE), %rcx 127 movq %rcx, %cr4; # turn off PGE 128 movq %cr3, %rcx; # flush TLB 129 movq %rcx, %cr3; 130 movq %rbx, %cr4; # turn PGE back on 131.Lloop: 132 testq %rdx, %rdx 133 jz .Ldone 134 135 /* get addresses from the pbe and copy the page */ 136 movq pbe_address(%rdx), %rsi 137 movq pbe_orig_address(%rdx), %rdi 138 movq $(PAGE_SIZE >> 3), %rcx 139 rep 140 movsq 141 142 /* progress to the next pbe */ 143 movq pbe_next(%rdx), %rdx 144 jmp .Lloop 145 146.Ldone: 147 /* jump to the restore_registers address from the image header */ 148 ANNOTATE_RETPOLINE_SAFE 149 jmpq *%r8 150SYM_FUNC_END(core_restore_code) 151