1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #ifndef _ASM_X86_KEXEC_H 3 #define _ASM_X86_KEXEC_H 4 5 #ifdef CONFIG_X86_32 6 # define PA_CONTROL_PAGE 0 7 # define VA_CONTROL_PAGE 1 8 # define PA_PGD 2 9 # define PA_SWAP_PAGE 3 10 # define PAGES_NR 4 11 #else 12 /* Size of each exception handler referenced by the IDT */ 13 # define KEXEC_DEBUG_EXC_HANDLER_SIZE 6 /* PUSHI, PUSHI, 2-byte JMP */ 14 #endif 15 16 #ifdef CONFIG_X86_64 17 18 #include <linux/bits.h> 19 20 #define RELOC_KERNEL_PRESERVE_CONTEXT BIT(0) 21 #define RELOC_KERNEL_CACHE_INCOHERENT BIT(1) 22 23 #endif 24 25 # define KEXEC_CONTROL_PAGE_SIZE 4096 26 # define KEXEC_CONTROL_CODE_MAX_SIZE 2048 27 28 #ifndef __ASSEMBLER__ 29 30 #include <linux/string.h> 31 #include <linux/kernel.h> 32 33 #include <asm/asm.h> 34 #include <asm/page.h> 35 #include <asm/ptrace.h> 36 37 struct kimage; 38 39 /* 40 * KEXEC_SOURCE_MEMORY_LIMIT maximum page get_free_page can return. 41 * I.e. Maximum page that is mapped directly into kernel memory, 42 * and kmap is not required. 43 * 44 * So far x86_64 is limited to 40 physical address bits. 45 */ 46 #ifdef CONFIG_X86_32 47 /* Maximum physical address we can use pages from */ 48 # define KEXEC_SOURCE_MEMORY_LIMIT (-1UL) 49 /* Maximum address we can reach in physical address mode */ 50 # define KEXEC_DESTINATION_MEMORY_LIMIT (-1UL) 51 /* Maximum address we can use for the control code buffer */ 52 # define KEXEC_CONTROL_MEMORY_LIMIT TASK_SIZE 53 54 55 /* The native architecture */ 56 # define KEXEC_ARCH KEXEC_ARCH_386 57 58 /* We can also handle crash dumps from 64 bit kernel. */ 59 # define vmcore_elf_check_arch_cross(x) ((x)->e_machine == EM_X86_64) 60 #else 61 /* Maximum physical address we can use pages from */ 62 # define KEXEC_SOURCE_MEMORY_LIMIT (MAXMEM-1) 63 /* Maximum address we can reach in physical address mode */ 64 # define KEXEC_DESTINATION_MEMORY_LIMIT (MAXMEM-1) 65 /* Maximum address we can use for the control pages */ 66 # define KEXEC_CONTROL_MEMORY_LIMIT (MAXMEM-1) 67 68 /* The native architecture */ 69 # define KEXEC_ARCH KEXEC_ARCH_X86_64 70 71 extern unsigned long kexec_va_control_page; 72 extern unsigned long kexec_pa_table_page; 73 extern unsigned long kexec_pa_swap_page; 74 extern gate_desc kexec_debug_idt[]; 75 extern unsigned char kexec_debug_exc_vectors[]; 76 extern uint16_t kexec_debug_8250_port; 77 extern unsigned long kexec_debug_8250_mmio32; 78 #endif 79 80 /* 81 * This function is responsible for capturing register states if coming 82 * via panic otherwise just fix up the ss and sp if coming via kernel 83 * mode exception. 84 */ 85 static inline void crash_setup_regs(struct pt_regs *newregs, 86 struct pt_regs *oldregs) 87 { 88 if (oldregs) { 89 memcpy(newregs, oldregs, sizeof(*newregs)); 90 } else { 91 asm volatile("mov %%" _ASM_BX ",%0" : "=m"(newregs->bx)); 92 asm volatile("mov %%" _ASM_CX ",%0" : "=m"(newregs->cx)); 93 asm volatile("mov %%" _ASM_DX ",%0" : "=m"(newregs->dx)); 94 asm volatile("mov %%" _ASM_SI ",%0" : "=m"(newregs->si)); 95 asm volatile("mov %%" _ASM_DI ",%0" : "=m"(newregs->di)); 96 asm volatile("mov %%" _ASM_BP ",%0" : "=m"(newregs->bp)); 97 asm volatile("mov %%" _ASM_AX ",%0" : "=m"(newregs->ax)); 98 asm volatile("mov %%" _ASM_SP ",%0" : "=m"(newregs->sp)); 99 #ifdef CONFIG_X86_64 100 asm volatile("mov %%r8,%0" : "=m"(newregs->r8)); 101 asm volatile("mov %%r9,%0" : "=m"(newregs->r9)); 102 asm volatile("mov %%r10,%0" : "=m"(newregs->r10)); 103 asm volatile("mov %%r11,%0" : "=m"(newregs->r11)); 104 asm volatile("mov %%r12,%0" : "=m"(newregs->r12)); 105 asm volatile("mov %%r13,%0" : "=m"(newregs->r13)); 106 asm volatile("mov %%r14,%0" : "=m"(newregs->r14)); 107 asm volatile("mov %%r15,%0" : "=m"(newregs->r15)); 108 #endif 109 asm volatile("mov %%ss,%k0" : "=a"(newregs->ss)); 110 asm volatile("mov %%cs,%k0" : "=a"(newregs->cs)); 111 #ifdef CONFIG_X86_32 112 asm volatile("mov %%ds,%k0" : "=a"(newregs->ds)); 113 asm volatile("mov %%es,%k0" : "=a"(newregs->es)); 114 #endif 115 asm volatile("pushf\n\t" 116 "pop %0" : "=m"(newregs->flags)); 117 newregs->ip = _THIS_IP_; 118 } 119 } 120 121 #ifdef CONFIG_X86_32 122 typedef asmlinkage unsigned long 123 relocate_kernel_fn(unsigned long indirection_page, 124 unsigned long control_page, 125 unsigned long start_address, 126 unsigned int has_pae, 127 unsigned int preserve_context); 128 #else 129 typedef unsigned long 130 relocate_kernel_fn(unsigned long indirection_page, 131 unsigned long pa_control_page, 132 unsigned long start_address, 133 unsigned int flags); 134 #endif 135 extern relocate_kernel_fn relocate_kernel; 136 #define ARCH_HAS_KIMAGE_ARCH 137 138 #ifdef CONFIG_X86_32 139 struct kimage_arch { 140 pgd_t *pgd; 141 #ifdef CONFIG_X86_PAE 142 pmd_t *pmd0; 143 pmd_t *pmd1; 144 #endif 145 pte_t *pte0; 146 pte_t *pte1; 147 }; 148 #else 149 struct kimage_arch { 150 /* 151 * This is a kimage control page, as it must not overlap with either 152 * source or destination address ranges. 153 */ 154 pgd_t *pgd; 155 /* 156 * The virtual mapping of the control code page itself is used only 157 * during the transition, while the current kernel's pages are all 158 * in place. Thus the intermediate page table pages used to map it 159 * are not control pages, but instead just normal pages obtained 160 * with get_zeroed_page(). And have to be tracked (below) so that 161 * they can be freed. 162 */ 163 p4d_t *p4d; 164 pud_t *pud; 165 pmd_t *pmd; 166 pte_t *pte; 167 }; 168 #endif /* CONFIG_X86_32 */ 169 170 #ifdef CONFIG_X86_64 171 /* 172 * Number of elements and order of elements in this structure should match 173 * with the ones in arch/x86/purgatory/entry64.S. If you make a change here 174 * make an appropriate change in purgatory too. 175 */ 176 struct kexec_entry64_regs { 177 uint64_t rax; 178 uint64_t rcx; 179 uint64_t rdx; 180 uint64_t rbx; 181 uint64_t rsp; 182 uint64_t rbp; 183 uint64_t rsi; 184 uint64_t rdi; 185 uint64_t r8; 186 uint64_t r9; 187 uint64_t r10; 188 uint64_t r11; 189 uint64_t r12; 190 uint64_t r13; 191 uint64_t r14; 192 uint64_t r15; 193 uint64_t rip; 194 }; 195 196 extern int arch_kexec_post_alloc_pages(void *vaddr, unsigned int pages, 197 gfp_t gfp); 198 #define arch_kexec_post_alloc_pages arch_kexec_post_alloc_pages 199 200 extern void arch_kexec_pre_free_pages(void *vaddr, unsigned int pages); 201 #define arch_kexec_pre_free_pages arch_kexec_pre_free_pages 202 203 void arch_kexec_protect_crashkres(void); 204 #define arch_kexec_protect_crashkres arch_kexec_protect_crashkres 205 206 void arch_kexec_unprotect_crashkres(void); 207 #define arch_kexec_unprotect_crashkres arch_kexec_unprotect_crashkres 208 209 #ifdef CONFIG_KEXEC_FILE 210 struct purgatory_info; 211 int arch_kexec_apply_relocations_add(struct purgatory_info *pi, 212 Elf_Shdr *section, 213 const Elf_Shdr *relsec, 214 const Elf_Shdr *symtab); 215 #define arch_kexec_apply_relocations_add arch_kexec_apply_relocations_add 216 217 int arch_kimage_file_post_load_cleanup(struct kimage *image); 218 #define arch_kimage_file_post_load_cleanup arch_kimage_file_post_load_cleanup 219 #endif 220 #endif 221 222 extern void kdump_nmi_shootdown_cpus(void); 223 224 #ifdef CONFIG_CRASH_HOTPLUG 225 void arch_crash_handle_hotplug_event(struct kimage *image, void *arg); 226 #define arch_crash_handle_hotplug_event arch_crash_handle_hotplug_event 227 228 int arch_crash_hotplug_support(struct kimage *image, unsigned long kexec_flags); 229 #define arch_crash_hotplug_support arch_crash_hotplug_support 230 231 unsigned int arch_crash_get_elfcorehdr_size(void); 232 #define crash_get_elfcorehdr_size arch_crash_get_elfcorehdr_size 233 #endif 234 235 #endif /* __ASSEMBLER__ */ 236 237 #endif /* _ASM_X86_KEXEC_H */ 238