arch/x86/mm/dump_pagetables.c

   1 /*
   2  * Debug helper to dump the current kernel pagetables of the system
   3  * so that we can see what the various memory ranges are set to.
   4  *
   5  * (C) Copyright 2008 Intel Corporation
   6  *
   7  * Author: Arjan van de Ven <arjan@linux.intel.com>
   8  *
   9  * This program is free software; you can redistribute it and/or
  10  * modify it under the terms of the GNU General Public License
  11  * as published by the Free Software Foundation; version 2
  12  * of the License.
  13  */
  14
  15 #include <linux/debugfs.h>
  16 #include <linux/kasan.h>
  17 #include <linux/mm.h>
  18 #include <linux/init.h>
  19 #include <linux/sched.h>
  20 #include <linux/seq_file.h>
  21 #include <linux/highmem.h>
  22 #include <linux/pci.h>
  23
  24 #include <asm/e820/types.h>
  25 #include <asm/pgtable.h>
  26
  27 /*
  28  * The dumper groups pagetable entries of the same type into one, and for
  29  * that it needs to keep some state when walking, and flush this state
  30  * when a "break" in the continuity is found.
  31  */
  32 struct pg_state {
  33         int level;
  34         pgprot_t current_prot;
  35         pgprotval_t effective_prot;
  36         unsigned long start_address;
  37         unsigned long current_address;
  38         const struct addr_marker *marker;
  39         unsigned long lines;
  40         bool to_dmesg;
  41         bool check_wx;
  42         unsigned long wx_pages;
  43 };
  44
  45 struct addr_marker {
  46         unsigned long start_address;
  47         const char *name;
  48         unsigned long max_lines;
  49 };
  50
  51 /* Address space markers hints */
  52
  53 #ifdef CONFIG_X86_64
  54
  55 enum address_markers_idx {
  56         USER_SPACE_NR = 0,
  57         KERNEL_SPACE_NR,
  58         LOW_KERNEL_NR,
  59 #if defined(CONFIG_MODIFY_LDT_SYSCALL) && defined(CONFIG_X86_5LEVEL)
  60         LDT_NR,
  61 #endif
  62         VMALLOC_START_NR,
  63         VMEMMAP_START_NR,
  64 #ifdef CONFIG_KASAN
  65         KASAN_SHADOW_START_NR,
  66         KASAN_SHADOW_END_NR,
  67 #endif
  68         CPU_ENTRY_AREA_NR,
  69 #if defined(CONFIG_MODIFY_LDT_SYSCALL) && !defined(CONFIG_X86_5LEVEL)
  70         LDT_NR,
  71 #endif
  72 #ifdef CONFIG_X86_ESPFIX64
  73         ESPFIX_START_NR,
  74 #endif
  75 #ifdef CONFIG_EFI
  76         EFI_END_NR,
  77 #endif
  78         HIGH_KERNEL_NR,
  79         MODULES_VADDR_NR,
  80         MODULES_END_NR,
  81         FIXADDR_START_NR,
  82         END_OF_SPACE_NR,
  83 };
  84
  85 static struct addr_marker address_markers[] = {
  86         [USER_SPACE_NR]         = { 0,                  "User Space" },
  87         [KERNEL_SPACE_NR]       = { (1UL << 63),        "Kernel Space" },
  88         [LOW_KERNEL_NR]         = { 0UL,                "Low Kernel Mapping" },
  89         [VMALLOC_START_NR]      = { 0UL,                "vmalloc() Area" },
  90         [VMEMMAP_START_NR]      = { 0UL,                "Vmemmap" },
  91 #ifdef CONFIG_KASAN
  92         /*
  93          * These fields get initialized with the (dynamic)
  94          * KASAN_SHADOW_{START,END} values in pt_dump_init().
  95          */
  96         [KASAN_SHADOW_START_NR] = { 0UL,                "KASAN shadow" },
  97         [KASAN_SHADOW_END_NR]   = { 0UL,                "KASAN shadow end" },
  98 #endif
  99 #ifdef CONFIG_MODIFY_LDT_SYSCALL
 100         [LDT_NR]                = { 0UL,                "LDT remap" },
 101 #endif
 102         [CPU_ENTRY_AREA_NR]     = { CPU_ENTRY_AREA_BASE,"CPU entry Area" },
 103 #ifdef CONFIG_X86_ESPFIX64
 104         [ESPFIX_START_NR]       = { ESPFIX_BASE_ADDR,   "ESPfix Area", 16 },
 105 #endif
 106 #ifdef CONFIG_EFI
 107         [EFI_END_NR]            = { EFI_VA_END,         "EFI Runtime Services" },
 108 #endif
 109         [HIGH_KERNEL_NR]        = { __START_KERNEL_map, "High Kernel Mapping" },
 110         [MODULES_VADDR_NR]      = { MODULES_VADDR,      "Modules" },
 111         [MODULES_END_NR]        = { MODULES_END,        "End Modules" },
 112         [FIXADDR_START_NR]      = { FIXADDR_START,      "Fixmap Area" },
 113         [END_OF_SPACE_NR]       = { -1,                 NULL }
 114 };
 115
 116 #define INIT_PGD        ((pgd_t *) &init_top_pgt)
 117
 118 #else /* CONFIG_X86_64 */
 119
 120 enum address_markers_idx {
 121         USER_SPACE_NR = 0,
 122         KERNEL_SPACE_NR,
 123         VMALLOC_START_NR,
 124         VMALLOC_END_NR,
 125 #ifdef CONFIG_HIGHMEM
 126         PKMAP_BASE_NR,
 127 #endif
 128 #ifdef CONFIG_MODIFY_LDT_SYSCALL
 129         LDT_NR,
 130 #endif
 131         CPU_ENTRY_AREA_NR,
 132         FIXADDR_START_NR,
 133         END_OF_SPACE_NR,
 134 };
 135
 136 static struct addr_marker address_markers[] = {
 137         [USER_SPACE_NR]         = { 0,                  "User Space" },
 138         [KERNEL_SPACE_NR]       = { PAGE_OFFSET,        "Kernel Mapping" },
 139         [VMALLOC_START_NR]      = { 0UL,                "vmalloc() Area" },
 140         [VMALLOC_END_NR]        = { 0UL,                "vmalloc() End" },
 141 #ifdef CONFIG_HIGHMEM
 142         [PKMAP_BASE_NR]         = { 0UL,                "Persistent kmap() Area" },
 143 #endif
 144 #ifdef CONFIG_MODIFY_LDT_SYSCALL
 145         [LDT_NR]                = { 0UL,                "LDT remap" },
 146 #endif
 147         [CPU_ENTRY_AREA_NR]     = { 0UL,                "CPU entry area" },
 148         [FIXADDR_START_NR]      = { 0UL,                "Fixmap area" },
 149         [END_OF_SPACE_NR]       = { -1,                 NULL }
 150 };
 151
 152 #define INIT_PGD        (swapper_pg_dir)
 153
 154 #endif /* !CONFIG_X86_64 */
 155
 156 /* Multipliers for offsets within the PTEs */
 157 #define PTE_LEVEL_MULT (PAGE_SIZE)
 158 #define PMD_LEVEL_MULT (PTRS_PER_PTE * PTE_LEVEL_MULT)
 159 #define PUD_LEVEL_MULT (PTRS_PER_PMD * PMD_LEVEL_MULT)
 160 #define P4D_LEVEL_MULT (PTRS_PER_PUD * PUD_LEVEL_MULT)
 161 #define PGD_LEVEL_MULT (PTRS_PER_P4D * P4D_LEVEL_MULT)
 162
 163 #define pt_dump_seq_printf(m, to_dmesg, fmt, args...)           \
 164 ({                                                              \
 165         if (to_dmesg)                                   \
 166                 printk(KERN_INFO fmt, ##args);                  \
 167         else                                                    \
 168                 if (m)                                          \
 169                         seq_printf(m, fmt, ##args);             \
 170 })
 171
 172 #define pt_dump_cont_printf(m, to_dmesg, fmt, args...)          \
 173 ({                                                              \
 174         if (to_dmesg)                                   \
 175                 printk(KERN_CONT fmt, ##args);                  \
 176         else                                                    \
 177                 if (m)                                          \
 178                         seq_printf(m, fmt, ##args);             \
 179 })
 180
 181 /*
 182  * Print a readable form of a pgprot_t to the seq_file
 183  */
 184 static void printk_prot(struct seq_file *m, pgprot_t prot, int level, bool dmsg)
 185 {
 186         pgprotval_t pr = pgprot_val(prot);
 187         static const char * const level_name[] =
 188                 { "cr3", "pgd", "p4d", "pud", "pmd", "pte" };
 189
 190         if (!(pr & _PAGE_PRESENT)) {
 191                 /* Not present */
 192                 pt_dump_cont_printf(m, dmsg, "                              ");
 193         } else {
 194                 if (pr & _PAGE_USER)
 195                         pt_dump_cont_printf(m, dmsg, "USR ");
 196                 else
 197                         pt_dump_cont_printf(m, dmsg, "    ");
 198                 if (pr & _PAGE_RW)
 199                         pt_dump_cont_printf(m, dmsg, "RW ");
 200                 else
 201                         pt_dump_cont_printf(m, dmsg, "ro ");
 202                 if (pr & _PAGE_PWT)
 203                         pt_dump_cont_printf(m, dmsg, "PWT ");
 204                 else
 205                         pt_dump_cont_printf(m, dmsg, "    ");
 206                 if (pr & _PAGE_PCD)
 207                         pt_dump_cont_printf(m, dmsg, "PCD ");
 208                 else
 209                         pt_dump_cont_printf(m, dmsg, "    ");
 210
 211                 /* Bit 7 has a different meaning on level 3 vs 4 */
 212                 if (level <= 4 && pr & _PAGE_PSE)
 213                         pt_dump_cont_printf(m, dmsg, "PSE ");
 214                 else
 215                         pt_dump_cont_printf(m, dmsg, "    ");
 216                 if ((level == 5 && pr & _PAGE_PAT) ||
 217                     ((level == 4 || level == 3) && pr & _PAGE_PAT_LARGE))
 218                         pt_dump_cont_printf(m, dmsg, "PAT ");
 219                 else
 220                         pt_dump_cont_printf(m, dmsg, "    ");
 221                 if (pr & _PAGE_GLOBAL)
 222                         pt_dump_cont_printf(m, dmsg, "GLB ");
 223                 else
 224                         pt_dump_cont_printf(m, dmsg, "    ");
 225                 if (pr & _PAGE_NX)
 226                         pt_dump_cont_printf(m, dmsg, "NX ");
 227                 else
 228                         pt_dump_cont_printf(m, dmsg, "x  ");
 229         }
 230         pt_dump_cont_printf(m, dmsg, "%s\n", level_name[level]);
 231 }
 232
 233 /*
 234  * On 64 bits, sign-extend the 48 bit address to 64 bit
 235  */
 236 static unsigned long normalize_addr(unsigned long u)
 237 {
 238         int shift;
 239         if (!IS_ENABLED(CONFIG_X86_64))
 240                 return u;
 241
 242         shift = 64 - (__VIRTUAL_MASK_SHIFT + 1);
 243         return (signed long)(u << shift) >> shift;
 244 }
 245
 246 static void note_wx(struct pg_state *st)
 247 {
 248         unsigned long npages;
 249
 250         npages = (st->current_address - st->start_address) / PAGE_SIZE;
 251
 252 #ifdef CONFIG_PCI_BIOS
 253         /*
 254          * If PCI BIOS is enabled, the PCI BIOS area is forced to WX.
 255          * Inform about it, but avoid the warning.
 256          */
 257         if (pcibios_enabled && st->start_address >= PAGE_OFFSET + BIOS_BEGIN &&
 258             st->current_address <= PAGE_OFFSET + BIOS_END) {
 259                 pr_warn_once("x86/mm: PCI BIOS W+X mapping %lu pages\n", npages);
 260                 return;
 261         }
 262 #endif
 263         /* Account the WX pages */
 264         st->wx_pages += npages;
 265         WARN_ONCE(1, "x86/mm: Found insecure W+X mapping at address %pS\n",
 266                   (void *)st->start_address);
 267 }
 268
 269 /*
 270  * This function gets called on a break in a continuous series
 271  * of PTE entries; the next one is different so we need to
 272  * print what we collected so far.
 273  */
 274 static void note_page(struct seq_file *m, struct pg_state *st,
 275                       pgprot_t new_prot, pgprotval_t new_eff, int level)
 276 {
 277         pgprotval_t prot, cur, eff;
 278         static const char units[] = "BKMGTPE";
 279
 280         /*
 281          * If we have a "break" in the series, we need to flush the state that
 282          * we have now. "break" is either changing perms, levels or
 283          * address space marker.
 284          */
 285         prot = pgprot_val(new_prot);
 286         cur = pgprot_val(st->current_prot);
 287         eff = st->effective_prot;
 288
 289         if (!st->level) {
 290                 /* First entry */
 291                 st->current_prot = new_prot;
 292                 st->effective_prot = new_eff;
 293                 st->level = level;
 294                 st->marker = address_markers;
 295                 st->lines = 0;
 296                 pt_dump_seq_printf(m, st->to_dmesg, "---[ %s ]---\n",
 297                                    st->marker->name);
 298         } else if (prot != cur || new_eff != eff || level != st->level ||
 299                    st->current_address >= st->marker[1].start_address) {
 300                 const char *unit = units;
 301                 unsigned long delta;
 302                 int width = sizeof(unsigned long) * 2;
 303
 304                 if (st->check_wx && (eff & _PAGE_RW) && !(eff & _PAGE_NX))
 305                         note_wx(st);
 306
 307                 /*
 308                  * Now print the actual finished series
 309                  */
 310                 if (!st->marker->max_lines ||
 311                     st->lines < st->marker->max_lines) {
 312                         pt_dump_seq_printf(m, st->to_dmesg,
 313                                            "0x%0*lx-0x%0*lx   ",
 314                                            width, st->start_address,
 315                                            width, st->current_address);
 316
 317                         delta = st->current_address - st->start_address;
 318                         while (!(delta & 1023) && unit[1]) {
 319                                 delta >>= 10;
 320                                 unit++;
 321                         }
 322                         pt_dump_cont_printf(m, st->to_dmesg, "%9lu%c ",
 323                                             delta, *unit);
 324                         printk_prot(m, st->current_prot, st->level,
 325                                     st->to_dmesg);
 326                 }
 327                 st->lines++;
 328
 329                 /*
 330                  * We print markers for special areas of address space,
 331                  * such as the start of vmalloc space etc.
 332                  * This helps in the interpretation.
 333                  */
 334                 if (st->current_address >= st->marker[1].start_address) {
 335                         if (st->marker->max_lines &&
 336                             st->lines > st->marker->max_lines) {
 337                                 unsigned long nskip =
 338                                         st->lines - st->marker->max_lines;
 339                                 pt_dump_seq_printf(m, st->to_dmesg,
 340                                                    "... %lu entr%s skipped ... \n",
 341                                                    nskip,
 342                                                    nskip == 1 ? "y" : "ies");
 343                         }
 344                         st->marker++;
 345                         st->lines = 0;
 346                         pt_dump_seq_printf(m, st->to_dmesg, "---[ %s ]---\n",
 347                                            st->marker->name);
 348                 }
 349
 350                 st->start_address = st->current_address;
 351                 st->current_prot = new_prot;
 352                 st->effective_prot = new_eff;
 353                 st->level = level;
 354         }
 355 }
 356
 357 static inline pgprotval_t effective_prot(pgprotval_t prot1, pgprotval_t prot2)
 358 {
 359         return (prot1 & prot2 & (_PAGE_USER | _PAGE_RW)) |
 360                ((prot1 | prot2) & _PAGE_NX);
 361 }
 362
 363 static void walk_pte_level(struct seq_file *m, struct pg_state *st, pmd_t addr,
 364                            pgprotval_t eff_in, unsigned long P)
 365 {
 366         int i;
 367         pte_t *pte;
 368         pgprotval_t prot, eff;
 369
 370         for (i = 0; i < PTRS_PER_PTE; i++) {
 371                 st->current_address = normalize_addr(P + i * PTE_LEVEL_MULT);
 372                 pte = pte_offset_map(&addr, st->current_address);
 373                 prot = pte_flags(*pte);
 374                 eff = effective_prot(eff_in, prot);
 375                 note_page(m, st, __pgprot(prot), eff, 5);
 376                 pte_unmap(pte);
 377         }
 378 }
 379 #ifdef CONFIG_KASAN
 380
 381 /*
 382  * This is an optimization for KASAN=y case. Since all kasan page tables
 383  * eventually point to the kasan_zero_page we could call note_page()
 384  * right away without walking through lower level page tables. This saves
 385  * us dozens of seconds (minutes for 5-level config) while checking for
 386  * W+X mapping or reading kernel_page_tables debugfs file.
 387  */
 388 static inline bool kasan_page_table(struct seq_file *m, struct pg_state *st,
 389                                 void *pt)
 390 {
 391         if (__pa(pt) == __pa(kasan_zero_pmd) ||
 392             (pgtable_l5_enabled() && __pa(pt) == __pa(kasan_zero_p4d)) ||
 393             __pa(pt) == __pa(kasan_zero_pud)) {
 394                 pgprotval_t prot = pte_flags(kasan_zero_pte[0]);
 395                 note_page(m, st, __pgprot(prot), 0, 5);
 396                 return true;
 397         }
 398         return false;
 399 }
 400 #else
 401 static inline bool kasan_page_table(struct seq_file *m, struct pg_state *st,
 402                                 void *pt)
 403 {
 404         return false;
 405 }
 406 #endif
 407
 408 #if PTRS_PER_PMD > 1
 409
 410 static void walk_pmd_level(struct seq_file *m, struct pg_state *st, pud_t addr,
 411                            pgprotval_t eff_in, unsigned long P)
 412 {
 413         int i;
 414         pmd_t *start, *pmd_start;
 415         pgprotval_t prot, eff;
 416
 417         pmd_start = start = (pmd_t *)pud_page_vaddr(addr);
 418         for (i = 0; i < PTRS_PER_PMD; i++) {
 419                 st->current_address = normalize_addr(P + i * PMD_LEVEL_MULT);
 420                 if (!pmd_none(*start)) {
 421                         prot = pmd_flags(*start);
 422                         eff = effective_prot(eff_in, prot);
 423                         if (pmd_large(*start) || !pmd_present(*start)) {
 424                                 note_page(m, st, __pgprot(prot), eff, 4);
 425                         } else if (!kasan_page_table(m, st, pmd_start)) {
 426                                 walk_pte_level(m, st, *start, eff,
 427                                                P + i * PMD_LEVEL_MULT);
 428                         }
 429                 } else
 430                         note_page(m, st, __pgprot(0), 0, 4);
 431                 start++;
 432         }
 433 }
 434
 435 #else
 436 #define walk_pmd_level(m,s,a,e,p) walk_pte_level(m,s,__pmd(pud_val(a)),e,p)
 437 #define pud_large(a) pmd_large(__pmd(pud_val(a)))
 438 #define pud_none(a)  pmd_none(__pmd(pud_val(a)))
 439 #endif
 440
 441 #if PTRS_PER_PUD > 1
 442
 443 static void walk_pud_level(struct seq_file *m, struct pg_state *st, p4d_t addr,
 444                            pgprotval_t eff_in, unsigned long P)
 445 {
 446         int i;
 447         pud_t *start, *pud_start;
 448         pgprotval_t prot, eff;
 449         pud_t *prev_pud = NULL;
 450
 451         pud_start = start = (pud_t *)p4d_page_vaddr(addr);
 452
 453         for (i = 0; i < PTRS_PER_PUD; i++) {
 454                 st->current_address = normalize_addr(P + i * PUD_LEVEL_MULT);
 455                 if (!pud_none(*start)) {
 456                         prot = pud_flags(*start);
 457                         eff = effective_prot(eff_in, prot);
 458                         if (pud_large(*start) || !pud_present(*start)) {
 459                                 note_page(m, st, __pgprot(prot), eff, 3);
 460                         } else if (!kasan_page_table(m, st, pud_start)) {
 461                                 walk_pmd_level(m, st, *start, eff,
 462                                                P + i * PUD_LEVEL_MULT);
 463                         }
 464                 } else
 465                         note_page(m, st, __pgprot(0), 0, 3);
 466
 467                 prev_pud = start;
 468                 start++;
 469         }
 470 }
 471
 472 #else
 473 #define walk_pud_level(m,s,a,e,p) walk_pmd_level(m,s,__pud(p4d_val(a)),e,p)
 474 #define p4d_large(a) pud_large(__pud(p4d_val(a)))
 475 #define p4d_none(a)  pud_none(__pud(p4d_val(a)))
 476 #endif
 477
 478 static void walk_p4d_level(struct seq_file *m, struct pg_state *st, pgd_t addr,
 479                            pgprotval_t eff_in, unsigned long P)
 480 {
 481         int i;
 482         p4d_t *start, *p4d_start;
 483         pgprotval_t prot, eff;
 484
 485         if (PTRS_PER_P4D == 1)
 486                 return walk_pud_level(m, st, __p4d(pgd_val(addr)), eff_in, P);
 487
 488         p4d_start = start = (p4d_t *)pgd_page_vaddr(addr);
 489
 490         for (i = 0; i < PTRS_PER_P4D; i++) {
 491                 st->current_address = normalize_addr(P + i * P4D_LEVEL_MULT);
 492                 if (!p4d_none(*start)) {
 493                         prot = p4d_flags(*start);
 494                         eff = effective_prot(eff_in, prot);
 495                         if (p4d_large(*start) || !p4d_present(*start)) {
 496                                 note_page(m, st, __pgprot(prot), eff, 2);
 497                         } else if (!kasan_page_table(m, st, p4d_start)) {
 498                                 walk_pud_level(m, st, *start, eff,
 499                                                P + i * P4D_LEVEL_MULT);
 500                         }
 501                 } else
 502                         note_page(m, st, __pgprot(0), 0, 2);
 503
 504                 start++;
 505         }
 506 }
 507
 508 #define pgd_large(a) (pgtable_l5_enabled() ? pgd_large(a) : p4d_large(__p4d(pgd_val(a))))
 509 #define pgd_none(a)  (pgtable_l5_enabled() ? pgd_none(a) : p4d_none(__p4d(pgd_val(a))))
 510
 511 static inline bool is_hypervisor_range(int idx)
 512 {
 513 #ifdef CONFIG_X86_64
 514         /*
 515          * ffff800000000000 - ffff87ffffffffff is reserved for
 516          * the hypervisor.
 517          */
 518         return  (idx >= pgd_index(__PAGE_OFFSET) - 16) &&
 519                 (idx <  pgd_index(__PAGE_OFFSET));
 520 #else
 521         return false;
 522 #endif
 523 }
 524
 525 static void ptdump_walk_pgd_level_core(struct seq_file *m, pgd_t *pgd,
 526                                        bool checkwx, bool dmesg)
 527 {
 528         pgd_t *start = INIT_PGD;
 529         pgprotval_t prot, eff;
 530         int i;
 531         struct pg_state st = {};
 532
 533         if (pgd) {
 534                 start = pgd;
 535                 st.to_dmesg = dmesg;
 536         }
 537
 538         st.check_wx = checkwx;
 539         if (checkwx)
 540                 st.wx_pages = 0;
 541
 542         for (i = 0; i < PTRS_PER_PGD; i++) {
 543                 st.current_address = normalize_addr(i * PGD_LEVEL_MULT);
 544                 if (!pgd_none(*start) && !is_hypervisor_range(i)) {
 545                         prot = pgd_flags(*start);
 546 #ifdef CONFIG_X86_PAE
 547                         eff = _PAGE_USER | _PAGE_RW;
 548 #else
 549                         eff = prot;
 550 #endif
 551                         if (pgd_large(*start) || !pgd_present(*start)) {
 552                                 note_page(m, &st, __pgprot(prot), eff, 1);
 553                         } else {
 554                                 walk_p4d_level(m, &st, *start, eff,
 555                                                i * PGD_LEVEL_MULT);
 556                         }
 557                 } else
 558                         note_page(m, &st, __pgprot(0), 0, 1);
 559
 560                 cond_resched();
 561                 start++;
 562         }
 563
 564         /* Flush out the last page */
 565         st.current_address = normalize_addr(PTRS_PER_PGD*PGD_LEVEL_MULT);
 566         note_page(m, &st, __pgprot(0), 0, 0);
 567         if (!checkwx)
 568                 return;
 569         if (st.wx_pages)
 570                 pr_info("x86/mm: Checked W+X mappings: FAILED, %lu W+X pages found.\n",
 571                         st.wx_pages);
 572         else
 573                 pr_info("x86/mm: Checked W+X mappings: passed, no W+X pages found.\n");
 574 }
 575
 576 void ptdump_walk_pgd_level(struct seq_file *m, pgd_t *pgd)
 577 {
 578         ptdump_walk_pgd_level_core(m, pgd, false, true);
 579 }
 580
 581 void ptdump_walk_pgd_level_debugfs(struct seq_file *m, pgd_t *pgd, bool user)
 582 {
 583 #ifdef CONFIG_PAGE_TABLE_ISOLATION
 584         if (user && static_cpu_has(X86_FEATURE_PTI))
 585                 pgd = kernel_to_user_pgdp(pgd);
 586 #endif
 587         ptdump_walk_pgd_level_core(m, pgd, false, false);
 588 }
 589 EXPORT_SYMBOL_GPL(ptdump_walk_pgd_level_debugfs);
 590
 591 void ptdump_walk_user_pgd_level_checkwx(void)
 592 {
 593 #ifdef CONFIG_PAGE_TABLE_ISOLATION
 594         pgd_t *pgd = INIT_PGD;
 595
 596         if (!(__supported_pte_mask & _PAGE_NX) ||
 597             !static_cpu_has(X86_FEATURE_PTI))
 598                 return;
 599
 600         pr_info("x86/mm: Checking user space page tables\n");
 601         pgd = kernel_to_user_pgdp(pgd);
 602         ptdump_walk_pgd_level_core(NULL, pgd, true, false);
 603 #endif
 604 }
 605
 606 void ptdump_walk_pgd_level_checkwx(void)
 607 {
 608         ptdump_walk_pgd_level_core(NULL, NULL, true, false);
 609 }
 610
 611 static int __init pt_dump_init(void)
 612 {
 613         /*
 614          * Various markers are not compile-time constants, so assign them
 615          * here.
 616          */
 617 #ifdef CONFIG_X86_64
 618         address_markers[LOW_KERNEL_NR].start_address = PAGE_OFFSET;
 619         address_markers[VMALLOC_START_NR].start_address = VMALLOC_START;
 620         address_markers[VMEMMAP_START_NR].start_address = VMEMMAP_START;
 621 #ifdef CONFIG_MODIFY_LDT_SYSCALL
 622         address_markers[LDT_NR].start_address = LDT_BASE_ADDR;
 623 #endif
 624 #ifdef CONFIG_KASAN
 625         address_markers[KASAN_SHADOW_START_NR].start_address = KASAN_SHADOW_START;
 626         address_markers[KASAN_SHADOW_END_NR].start_address = KASAN_SHADOW_END;
 627 #endif
 628 #endif
 629 #ifdef CONFIG_X86_32
 630         address_markers[VMALLOC_START_NR].start_address = VMALLOC_START;
 631         address_markers[VMALLOC_END_NR].start_address = VMALLOC_END;
 632 # ifdef CONFIG_HIGHMEM
 633         address_markers[PKMAP_BASE_NR].start_address = PKMAP_BASE;
 634 # endif
 635         address_markers[FIXADDR_START_NR].start_address = FIXADDR_START;
 636         address_markers[CPU_ENTRY_AREA_NR].start_address = CPU_ENTRY_AREA_BASE;
 637 # ifdef CONFIG_MODIFY_LDT_SYSCALL
 638         address_markers[LDT_NR].start_address = LDT_BASE_ADDR;
 639 # endif
 640 #endif
 641         return 0;
 642 }
 643 __initcall(pt_dump_init);