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8#define DISABLE_BRANCH_PROFILING
9
10
11#define USE_EARLY_PGTABLE_L5
12
13#include <linux/init.h>
14#include <linux/linkage.h>
15#include <linux/types.h>
16#include <linux/kernel.h>
17#include <linux/string.h>
18#include <linux/percpu.h>
19#include <linux/start_kernel.h>
20#include <linux/io.h>
21#include <linux/memblock.h>
22#include <linux/mem_encrypt.h>
23
24#include <asm/processor.h>
25#include <asm/proto.h>
26#include <asm/smp.h>
27#include <asm/setup.h>
28#include <asm/desc.h>
29#include <asm/pgtable.h>
30#include <asm/tlbflush.h>
31#include <asm/sections.h>
32#include <asm/kdebug.h>
33#include <asm/e820/api.h>
34#include <asm/bios_ebda.h>
35#include <asm/bootparam_utils.h>
36#include <asm/microcode.h>
37#include <asm/kasan.h>
38
39
40
41
42extern pmd_t early_dynamic_pgts[EARLY_DYNAMIC_PAGE_TABLES][PTRS_PER_PMD];
43static unsigned int __initdata next_early_pgt;
44pmdval_t early_pmd_flags = __PAGE_KERNEL_LARGE & ~(_PAGE_GLOBAL | _PAGE_NX);
45
46#ifdef CONFIG_X86_5LEVEL
47unsigned int __pgtable_l5_enabled __ro_after_init;
48unsigned int pgdir_shift __ro_after_init = 39;
49EXPORT_SYMBOL(pgdir_shift);
50unsigned int ptrs_per_p4d __ro_after_init = 1;
51EXPORT_SYMBOL(ptrs_per_p4d);
52#endif
53
54#ifdef CONFIG_DYNAMIC_MEMORY_LAYOUT
55unsigned long page_offset_base __ro_after_init = __PAGE_OFFSET_BASE_L4;
56EXPORT_SYMBOL(page_offset_base);
57unsigned long vmalloc_base __ro_after_init = __VMALLOC_BASE_L4;
58EXPORT_SYMBOL(vmalloc_base);
59unsigned long vmemmap_base __ro_after_init = __VMEMMAP_BASE_L4;
60EXPORT_SYMBOL(vmemmap_base);
61#endif
62
63#define __head __section(.head.text)
64
65static void __head *fixup_pointer(void *ptr, unsigned long physaddr)
66{
67 return ptr - (void *)_text + (void *)physaddr;
68}
69
70static unsigned long __head *fixup_long(void *ptr, unsigned long physaddr)
71{
72 return fixup_pointer(ptr, physaddr);
73}
74
75#ifdef CONFIG_X86_5LEVEL
76static unsigned int __head *fixup_int(void *ptr, unsigned long physaddr)
77{
78 return fixup_pointer(ptr, physaddr);
79}
80
81static bool __head check_la57_support(unsigned long physaddr)
82{
83
84
85
86
87 if (!(native_read_cr4() & X86_CR4_LA57))
88 return false;
89
90 *fixup_int(&__pgtable_l5_enabled, physaddr) = 1;
91 *fixup_int(&pgdir_shift, physaddr) = 48;
92 *fixup_int(&ptrs_per_p4d, physaddr) = 512;
93 *fixup_long(&page_offset_base, physaddr) = __PAGE_OFFSET_BASE_L5;
94 *fixup_long(&vmalloc_base, physaddr) = __VMALLOC_BASE_L5;
95 *fixup_long(&vmemmap_base, physaddr) = __VMEMMAP_BASE_L5;
96
97 return true;
98}
99#else
100static bool __head check_la57_support(unsigned long physaddr)
101{
102 return false;
103}
104#endif
105
106
107
108
109
110
111
112unsigned long __head __startup_64(unsigned long physaddr,
113 struct boot_params *bp)
114{
115 unsigned long load_delta, *p;
116 unsigned long pgtable_flags;
117 pgdval_t *pgd;
118 p4dval_t *p4d;
119 pudval_t *pud;
120 pmdval_t *pmd, pmd_entry;
121 pteval_t *mask_ptr;
122 bool la57;
123 int i;
124 unsigned int *next_pgt_ptr;
125
126 la57 = check_la57_support(physaddr);
127
128
129 if (physaddr >> MAX_PHYSMEM_BITS)
130 for (;;);
131
132
133
134
135
136 load_delta = physaddr - (unsigned long)(_text - __START_KERNEL_map);
137
138
139 if (load_delta & ~PMD_PAGE_MASK)
140 for (;;);
141
142
143 sme_enable(bp);
144
145
146 load_delta += sme_get_me_mask();
147
148
149
150 pgd = fixup_pointer(&early_top_pgt, physaddr);
151 p = pgd + pgd_index(__START_KERNEL_map);
152 if (la57)
153 *p = (unsigned long)level4_kernel_pgt;
154 else
155 *p = (unsigned long)level3_kernel_pgt;
156 *p += _PAGE_TABLE_NOENC - __START_KERNEL_map + load_delta;
157
158 if (la57) {
159 p4d = fixup_pointer(&level4_kernel_pgt, physaddr);
160 p4d[511] += load_delta;
161 }
162
163 pud = fixup_pointer(&level3_kernel_pgt, physaddr);
164 pud[510] += load_delta;
165 pud[511] += load_delta;
166
167 pmd = fixup_pointer(level2_fixmap_pgt, physaddr);
168 pmd[506] += load_delta;
169
170
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172
173
174
175
176
177 next_pgt_ptr = fixup_pointer(&next_early_pgt, physaddr);
178 pud = fixup_pointer(early_dynamic_pgts[(*next_pgt_ptr)++], physaddr);
179 pmd = fixup_pointer(early_dynamic_pgts[(*next_pgt_ptr)++], physaddr);
180
181 pgtable_flags = _KERNPG_TABLE_NOENC + sme_get_me_mask();
182
183 if (la57) {
184 p4d = fixup_pointer(early_dynamic_pgts[next_early_pgt++], physaddr);
185
186 i = (physaddr >> PGDIR_SHIFT) % PTRS_PER_PGD;
187 pgd[i + 0] = (pgdval_t)p4d + pgtable_flags;
188 pgd[i + 1] = (pgdval_t)p4d + pgtable_flags;
189
190 i = (physaddr >> P4D_SHIFT) % PTRS_PER_P4D;
191 p4d[i + 0] = (pgdval_t)pud + pgtable_flags;
192 p4d[i + 1] = (pgdval_t)pud + pgtable_flags;
193 } else {
194 i = (physaddr >> PGDIR_SHIFT) % PTRS_PER_PGD;
195 pgd[i + 0] = (pgdval_t)pud + pgtable_flags;
196 pgd[i + 1] = (pgdval_t)pud + pgtable_flags;
197 }
198
199 i = (physaddr >> PUD_SHIFT) % PTRS_PER_PUD;
200 pud[i + 0] = (pudval_t)pmd + pgtable_flags;
201 pud[i + 1] = (pudval_t)pmd + pgtable_flags;
202
203 pmd_entry = __PAGE_KERNEL_LARGE_EXEC & ~_PAGE_GLOBAL;
204
205 mask_ptr = fixup_pointer(&__supported_pte_mask, physaddr);
206 pmd_entry &= *mask_ptr;
207 pmd_entry += sme_get_me_mask();
208 pmd_entry += physaddr;
209
210 for (i = 0; i < DIV_ROUND_UP(_end - _text, PMD_SIZE); i++) {
211 int idx = i + (physaddr >> PMD_SHIFT) % PTRS_PER_PMD;
212 pmd[idx] = pmd_entry + i * PMD_SIZE;
213 }
214
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216
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218
219
220
221
222 pmd = fixup_pointer(level2_kernel_pgt, physaddr);
223 for (i = 0; i < PTRS_PER_PMD; i++) {
224 if (pmd[i] & _PAGE_PRESENT)
225 pmd[i] += load_delta;
226 }
227
228
229
230
231
232 *fixup_long(&phys_base, physaddr) += load_delta - sme_get_me_mask();
233
234
235 sme_encrypt_kernel(bp);
236
237
238
239
240
241 return sme_get_me_mask();
242}
243
244unsigned long __startup_secondary_64(void)
245{
246
247
248
249
250 return sme_get_me_mask();
251}
252
253
254static void __init reset_early_page_tables(void)
255{
256 memset(early_top_pgt, 0, sizeof(pgd_t)*(PTRS_PER_PGD-1));
257 next_early_pgt = 0;
258 write_cr3(__sme_pa_nodebug(early_top_pgt));
259}
260
261
262int __init __early_make_pgtable(unsigned long address, pmdval_t pmd)
263{
264 unsigned long physaddr = address - __PAGE_OFFSET;
265 pgdval_t pgd, *pgd_p;
266 p4dval_t p4d, *p4d_p;
267 pudval_t pud, *pud_p;
268 pmdval_t *pmd_p;
269
270
271 if (physaddr >= MAXMEM || read_cr3_pa() != __pa_nodebug(early_top_pgt))
272 return -1;
273
274again:
275 pgd_p = &early_top_pgt[pgd_index(address)].pgd;
276 pgd = *pgd_p;
277
278
279
280
281
282
283 if (!pgtable_l5_enabled())
284 p4d_p = pgd_p;
285 else if (pgd)
286 p4d_p = (p4dval_t *)((pgd & PTE_PFN_MASK) + __START_KERNEL_map - phys_base);
287 else {
288 if (next_early_pgt >= EARLY_DYNAMIC_PAGE_TABLES) {
289 reset_early_page_tables();
290 goto again;
291 }
292
293 p4d_p = (p4dval_t *)early_dynamic_pgts[next_early_pgt++];
294 memset(p4d_p, 0, sizeof(*p4d_p) * PTRS_PER_P4D);
295 *pgd_p = (pgdval_t)p4d_p - __START_KERNEL_map + phys_base + _KERNPG_TABLE;
296 }
297 p4d_p += p4d_index(address);
298 p4d = *p4d_p;
299
300 if (p4d)
301 pud_p = (pudval_t *)((p4d & PTE_PFN_MASK) + __START_KERNEL_map - phys_base);
302 else {
303 if (next_early_pgt >= EARLY_DYNAMIC_PAGE_TABLES) {
304 reset_early_page_tables();
305 goto again;
306 }
307
308 pud_p = (pudval_t *)early_dynamic_pgts[next_early_pgt++];
309 memset(pud_p, 0, sizeof(*pud_p) * PTRS_PER_PUD);
310 *p4d_p = (p4dval_t)pud_p - __START_KERNEL_map + phys_base + _KERNPG_TABLE;
311 }
312 pud_p += pud_index(address);
313 pud = *pud_p;
314
315 if (pud)
316 pmd_p = (pmdval_t *)((pud & PTE_PFN_MASK) + __START_KERNEL_map - phys_base);
317 else {
318 if (next_early_pgt >= EARLY_DYNAMIC_PAGE_TABLES) {
319 reset_early_page_tables();
320 goto again;
321 }
322
323 pmd_p = (pmdval_t *)early_dynamic_pgts[next_early_pgt++];
324 memset(pmd_p, 0, sizeof(*pmd_p) * PTRS_PER_PMD);
325 *pud_p = (pudval_t)pmd_p - __START_KERNEL_map + phys_base + _KERNPG_TABLE;
326 }
327 pmd_p[pmd_index(address)] = pmd;
328
329 return 0;
330}
331
332int __init early_make_pgtable(unsigned long address)
333{
334 unsigned long physaddr = address - __PAGE_OFFSET;
335 pmdval_t pmd;
336
337 pmd = (physaddr & PMD_MASK) + early_pmd_flags;
338
339 return __early_make_pgtable(address, pmd);
340}
341
342
343
344static void __init clear_bss(void)
345{
346 memset(__bss_start, 0,
347 (unsigned long) __bss_stop - (unsigned long) __bss_start);
348}
349
350static unsigned long get_cmd_line_ptr(void)
351{
352 unsigned long cmd_line_ptr = boot_params.hdr.cmd_line_ptr;
353
354 cmd_line_ptr |= (u64)boot_params.ext_cmd_line_ptr << 32;
355
356 return cmd_line_ptr;
357}
358
359static void __init copy_bootdata(char *real_mode_data)
360{
361 char * command_line;
362 unsigned long cmd_line_ptr;
363
364
365
366
367
368 sme_map_bootdata(real_mode_data);
369
370 memcpy(&boot_params, real_mode_data, sizeof boot_params);
371 sanitize_boot_params(&boot_params);
372 cmd_line_ptr = get_cmd_line_ptr();
373 if (cmd_line_ptr) {
374 command_line = __va(cmd_line_ptr);
375 memcpy(boot_command_line, command_line, COMMAND_LINE_SIZE);
376 }
377
378
379
380
381
382
383
384 sme_unmap_bootdata(real_mode_data);
385}
386
387asmlinkage __visible void __init x86_64_start_kernel(char * real_mode_data)
388{
389
390
391
392
393 BUILD_BUG_ON(MODULES_VADDR < __START_KERNEL_map);
394 BUILD_BUG_ON(MODULES_VADDR - __START_KERNEL_map < KERNEL_IMAGE_SIZE);
395 BUILD_BUG_ON(MODULES_LEN + KERNEL_IMAGE_SIZE > 2*PUD_SIZE);
396 BUILD_BUG_ON((__START_KERNEL_map & ~PMD_MASK) != 0);
397 BUILD_BUG_ON((MODULES_VADDR & ~PMD_MASK) != 0);
398 BUILD_BUG_ON(!(MODULES_VADDR > __START_KERNEL));
399 MAYBE_BUILD_BUG_ON(!(((MODULES_END - 1) & PGDIR_MASK) ==
400 (__START_KERNEL & PGDIR_MASK)));
401 BUILD_BUG_ON(__fix_to_virt(__end_of_fixed_addresses) <= MODULES_END);
402
403 cr4_init_shadow();
404
405
406 reset_early_page_tables();
407
408 clear_bss();
409
410 clear_page(init_top_pgt);
411
412
413
414
415
416
417 sme_early_init();
418
419 kasan_early_init();
420
421 idt_setup_early_handler();
422
423 copy_bootdata(__va(real_mode_data));
424
425
426
427
428 load_ucode_bsp();
429
430
431 init_top_pgt[511] = early_top_pgt[511];
432
433 x86_64_start_reservations(real_mode_data);
434}
435
436void __init x86_64_start_reservations(char *real_mode_data)
437{
438
439 if (!boot_params.hdr.version)
440 copy_bootdata(__va(real_mode_data));
441
442 x86_early_init_platform_quirks();
443
444 switch (boot_params.hdr.hardware_subarch) {
445 case X86_SUBARCH_INTEL_MID:
446 x86_intel_mid_early_setup();
447 break;
448 default:
449 break;
450 }
451
452 start_kernel();
453}
454