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1/*
2 * prepare to run common code
3 *
4 * Copyright (C) 2000 Andrea Arcangeli <andrea@suse.de> SuSE
5 */
6
7#define DISABLE_BRANCH_PROFILING
8#include <linux/init.h>
9#include <linux/linkage.h>
10#include <linux/types.h>
11#include <linux/kernel.h>
12#include <linux/string.h>
13#include <linux/percpu.h>
14#include <linux/start_kernel.h>
15#include <linux/io.h>
16#include <linux/memblock.h>
17
18#include <asm/processor.h>
19#include <asm/proto.h>
20#include <asm/smp.h>
21#include <asm/setup.h>
22#include <asm/desc.h>
23#include <asm/pgtable.h>
24#include <asm/tlbflush.h>
25#include <asm/sections.h>
26#include <asm/kdebug.h>
27#include <asm/e820.h>
28#include <asm/bios_ebda.h>
29#include <asm/bootparam_utils.h>
30#include <asm/microcode.h>
31#include <asm/kasan.h>
32
33/*
34 * Manage page tables very early on.
35 */
36extern pgd_t early_level4_pgt[PTRS_PER_PGD];
37extern pmd_t early_dynamic_pgts[EARLY_DYNAMIC_PAGE_TABLES][PTRS_PER_PMD];
38static unsigned int __initdata next_early_pgt = 2;
39pmdval_t early_pmd_flags = __PAGE_KERNEL_LARGE & ~(_PAGE_GLOBAL | _PAGE_NX);
40
41/* Wipe all early page tables except for the kernel symbol map */
42static void __init reset_early_page_tables(void)
43{
44 memset(early_level4_pgt, 0, sizeof(pgd_t)*(PTRS_PER_PGD-1));
45 next_early_pgt = 0;
46 write_cr3(__pa_nodebug(early_level4_pgt));
47}
48
49/* Create a new PMD entry */
50int __init early_make_pgtable(unsigned long address)
51{
52 unsigned long physaddr = address - __PAGE_OFFSET;
53 pgdval_t pgd, *pgd_p;
54 pudval_t pud, *pud_p;
55 pmdval_t pmd, *pmd_p;
56
57 /* Invalid address or early pgt is done ? */
58 if (physaddr >= MAXMEM || read_cr3() != __pa_nodebug(early_level4_pgt))
59 return -1;
60
61again:
62 pgd_p = &early_level4_pgt[pgd_index(address)].pgd;
63 pgd = *pgd_p;
64
65 /*
66 * The use of __START_KERNEL_map rather than __PAGE_OFFSET here is
67 * critical -- __PAGE_OFFSET would point us back into the dynamic
68 * range and we might end up looping forever...
69 */
70 if (pgd)
71 pud_p = (pudval_t *)((pgd & PTE_PFN_MASK) + __START_KERNEL_map - phys_base);
72 else {
73 if (next_early_pgt >= EARLY_DYNAMIC_PAGE_TABLES) {
74 reset_early_page_tables();
75 goto again;
76 }
77
78 pud_p = (pudval_t *)early_dynamic_pgts[next_early_pgt++];
79 memset(pud_p, 0, sizeof(*pud_p) * PTRS_PER_PUD);
80 *pgd_p = (pgdval_t)pud_p - __START_KERNEL_map + phys_base + _KERNPG_TABLE;
81 }
82 pud_p += pud_index(address);
83 pud = *pud_p;
84
85 if (pud)
86 pmd_p = (pmdval_t *)((pud & PTE_PFN_MASK) + __START_KERNEL_map - phys_base);
87 else {
88 if (next_early_pgt >= EARLY_DYNAMIC_PAGE_TABLES) {
89 reset_early_page_tables();
90 goto again;
91 }
92
93 pmd_p = (pmdval_t *)early_dynamic_pgts[next_early_pgt++];
94 memset(pmd_p, 0, sizeof(*pmd_p) * PTRS_PER_PMD);
95 *pud_p = (pudval_t)pmd_p - __START_KERNEL_map + phys_base + _KERNPG_TABLE;
96 }
97 pmd = (physaddr & PMD_MASK) + early_pmd_flags;
98 pmd_p[pmd_index(address)] = pmd;
99
100 return 0;
101}
102
103/* Don't add a printk in there. printk relies on the PDA which is not initialized
104 yet. */
105static void __init clear_bss(void)
106{
107 memset(__bss_start, 0,
108 (unsigned long) __bss_stop - (unsigned long) __bss_start);
109}
110
111static unsigned long get_cmd_line_ptr(void)
112{
113 unsigned long cmd_line_ptr = boot_params.hdr.cmd_line_ptr;
114
115 cmd_line_ptr |= (u64)boot_params.ext_cmd_line_ptr << 32;
116
117 return cmd_line_ptr;
118}
119
120static void __init copy_bootdata(char *real_mode_data)
121{
122 char * command_line;
123 unsigned long cmd_line_ptr;
124
125 memcpy(&boot_params, real_mode_data, sizeof boot_params);
126 sanitize_boot_params(&boot_params);
127 cmd_line_ptr = get_cmd_line_ptr();
128 if (cmd_line_ptr) {
129 command_line = __va(cmd_line_ptr);
130 memcpy(boot_command_line, command_line, COMMAND_LINE_SIZE);
131 }
132}
133
134asmlinkage __visible void __init x86_64_start_kernel(char * real_mode_data)
135{
136 int i;
137
138 /*
139 * Build-time sanity checks on the kernel image and module
140 * area mappings. (these are purely build-time and produce no code)
141 */
142 BUILD_BUG_ON(MODULES_VADDR < __START_KERNEL_map);
143 BUILD_BUG_ON(MODULES_VADDR - __START_KERNEL_map < KERNEL_IMAGE_SIZE);
144 BUILD_BUG_ON(MODULES_LEN + KERNEL_IMAGE_SIZE > 2*PUD_SIZE);
145 BUILD_BUG_ON((__START_KERNEL_map & ~PMD_MASK) != 0);
146 BUILD_BUG_ON((MODULES_VADDR & ~PMD_MASK) != 0);
147 BUILD_BUG_ON(!(MODULES_VADDR > __START_KERNEL));
148 BUILD_BUG_ON(!(((MODULES_END - 1) & PGDIR_MASK) ==
149 (__START_KERNEL & PGDIR_MASK)));
150 BUILD_BUG_ON(__fix_to_virt(__end_of_fixed_addresses) <= MODULES_END);
151
152 cr4_init_shadow();
153
154 /* Kill off the identity-map trampoline */
155 reset_early_page_tables();
156
157 clear_bss();
158
159 clear_page(init_level4_pgt);
160
161 kasan_early_init();
162
163 for (i = 0; i < NUM_EXCEPTION_VECTORS; i++)
164 set_intr_gate(i, early_idt_handler_array[i]);
165 load_idt((const struct desc_ptr *)&idt_descr);
166
167 copy_bootdata(__va(real_mode_data));
168
169 /*
170 * Load microcode early on BSP.
171 */
172 load_ucode_bsp();
173
174 /* set init_level4_pgt kernel high mapping*/
175 init_level4_pgt[511] = early_level4_pgt[511];
176
177 x86_64_start_reservations(real_mode_data);
178}
179
180void __init x86_64_start_reservations(char *real_mode_data)
181{
182 /* version is always not zero if it is copied */
183 if (!boot_params.hdr.version)
184 copy_bootdata(__va(real_mode_data));
185
186 x86_early_init_platform_quirks();
187
188 switch (boot_params.hdr.hardware_subarch) {
189 case X86_SUBARCH_INTEL_MID:
190 x86_intel_mid_early_setup();
191 break;
192 default:
193 break;
194 }
195
196 start_kernel();
197}
1/*
2 * prepare to run common code
3 *
4 * Copyright (C) 2000 Andrea Arcangeli <andrea@suse.de> SuSE
5 */
6
7#include <linux/init.h>
8#include <linux/linkage.h>
9#include <linux/types.h>
10#include <linux/kernel.h>
11#include <linux/string.h>
12#include <linux/percpu.h>
13#include <linux/start_kernel.h>
14#include <linux/io.h>
15#include <linux/memblock.h>
16
17#include <asm/processor.h>
18#include <asm/proto.h>
19#include <asm/smp.h>
20#include <asm/setup.h>
21#include <asm/desc.h>
22#include <asm/pgtable.h>
23#include <asm/tlbflush.h>
24#include <asm/sections.h>
25#include <asm/kdebug.h>
26#include <asm/e820.h>
27#include <asm/trampoline.h>
28#include <asm/bios_ebda.h>
29
30static void __init zap_identity_mappings(void)
31{
32 pgd_t *pgd = pgd_offset_k(0UL);
33 pgd_clear(pgd);
34 __flush_tlb_all();
35}
36
37/* Don't add a printk in there. printk relies on the PDA which is not initialized
38 yet. */
39static void __init clear_bss(void)
40{
41 memset(__bss_start, 0,
42 (unsigned long) __bss_stop - (unsigned long) __bss_start);
43}
44
45static void __init copy_bootdata(char *real_mode_data)
46{
47 char * command_line;
48
49 memcpy(&boot_params, real_mode_data, sizeof boot_params);
50 if (boot_params.hdr.cmd_line_ptr) {
51 command_line = __va(boot_params.hdr.cmd_line_ptr);
52 memcpy(boot_command_line, command_line, COMMAND_LINE_SIZE);
53 }
54}
55
56void __init x86_64_start_kernel(char * real_mode_data)
57{
58 int i;
59
60 /*
61 * Build-time sanity checks on the kernel image and module
62 * area mappings. (these are purely build-time and produce no code)
63 */
64 BUILD_BUG_ON(MODULES_VADDR < KERNEL_IMAGE_START);
65 BUILD_BUG_ON(MODULES_VADDR-KERNEL_IMAGE_START < KERNEL_IMAGE_SIZE);
66 BUILD_BUG_ON(MODULES_LEN + KERNEL_IMAGE_SIZE > 2*PUD_SIZE);
67 BUILD_BUG_ON((KERNEL_IMAGE_START & ~PMD_MASK) != 0);
68 BUILD_BUG_ON((MODULES_VADDR & ~PMD_MASK) != 0);
69 BUILD_BUG_ON(!(MODULES_VADDR > __START_KERNEL));
70 BUILD_BUG_ON(!(((MODULES_END - 1) & PGDIR_MASK) ==
71 (__START_KERNEL & PGDIR_MASK)));
72 BUILD_BUG_ON(__fix_to_virt(__end_of_fixed_addresses) <= MODULES_END);
73
74 /* clear bss before set_intr_gate with early_idt_handler */
75 clear_bss();
76
77 /* Make NULL pointers segfault */
78 zap_identity_mappings();
79
80 max_pfn_mapped = KERNEL_IMAGE_SIZE >> PAGE_SHIFT;
81
82 for (i = 0; i < NUM_EXCEPTION_VECTORS; i++) {
83#ifdef CONFIG_EARLY_PRINTK
84 set_intr_gate(i, &early_idt_handlers[i]);
85#else
86 set_intr_gate(i, early_idt_handler);
87#endif
88 }
89 load_idt((const struct desc_ptr *)&idt_descr);
90
91 if (console_loglevel == 10)
92 early_printk("Kernel alive\n");
93
94 x86_64_start_reservations(real_mode_data);
95}
96
97void __init x86_64_start_reservations(char *real_mode_data)
98{
99 copy_bootdata(__va(real_mode_data));
100
101 memblock_init();
102
103 memblock_x86_reserve_range(__pa_symbol(&_text), __pa_symbol(&__bss_stop), "TEXT DATA BSS");
104
105#ifdef CONFIG_BLK_DEV_INITRD
106 /* Reserve INITRD */
107 if (boot_params.hdr.type_of_loader && boot_params.hdr.ramdisk_image) {
108 /* Assume only end is not page aligned */
109 unsigned long ramdisk_image = boot_params.hdr.ramdisk_image;
110 unsigned long ramdisk_size = boot_params.hdr.ramdisk_size;
111 unsigned long ramdisk_end = PAGE_ALIGN(ramdisk_image + ramdisk_size);
112 memblock_x86_reserve_range(ramdisk_image, ramdisk_end, "RAMDISK");
113 }
114#endif
115
116 reserve_ebda_region();
117
118 /*
119 * At this point everything still needed from the boot loader
120 * or BIOS or kernel text should be early reserved or marked not
121 * RAM in e820. All other memory is free game.
122 */
123
124 start_kernel();
125}