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1// SPDX-License-Identifier: GPL-2.02/*3 * mm/debug.c4 *5 * mm/ specific debug routines.6 *7 */8 9#include <linux/kernel.h>10#include <linux/mm.h>11#include <linux/trace_events.h>12#include <linux/memcontrol.h>13#include <trace/events/mmflags.h>14#include <linux/migrate.h>15#include <linux/page_owner.h>16#include <linux/ctype.h>17 18#include "internal.h"19#include <trace/events/migrate.h>20 21/*22 * Define EM() and EMe() so that MIGRATE_REASON from trace/events/migrate.h can23 * be used to populate migrate_reason_names[].24 */25#undef EM26#undef EMe27#define EM(a, b) b,28#define EMe(a, b) b29 30const char *migrate_reason_names[MR_TYPES] = {31 MIGRATE_REASON32};33 34const struct trace_print_flags pageflag_names[] = {35 __def_pageflag_names,36 {0, NULL}37};38 39const struct trace_print_flags gfpflag_names[] = {40 __def_gfpflag_names,41 {0, NULL}42};43 44const struct trace_print_flags vmaflag_names[] = {45 __def_vmaflag_names,46 {0, NULL}47};48 49#define DEF_PAGETYPE_NAME(_name) [PGTY_##_name - 0xf0] = __stringify(_name)50 51static const char *page_type_names[] = {52 DEF_PAGETYPE_NAME(slab),53 DEF_PAGETYPE_NAME(hugetlb),54 DEF_PAGETYPE_NAME(offline),55 DEF_PAGETYPE_NAME(guard),56 DEF_PAGETYPE_NAME(table),57 DEF_PAGETYPE_NAME(buddy),58 DEF_PAGETYPE_NAME(unaccepted),59};60 61static const char *page_type_name(unsigned int page_type)62{63 unsigned i = (page_type >> 24) - 0xf0;64 65 if (i >= ARRAY_SIZE(page_type_names))66 return "unknown";67 return page_type_names[i];68}69 70static void __dump_folio(struct folio *folio, struct page *page,71 unsigned long pfn, unsigned long idx)72{73 struct address_space *mapping = folio_mapping(folio);74 int mapcount = atomic_read(&page->_mapcount);75 char *type = "";76 77 mapcount = page_mapcount_is_type(mapcount) ? 0 : mapcount + 1;78 pr_warn("page: refcount:%d mapcount:%d mapping:%p index:%#lx pfn:%#lx\n",79 folio_ref_count(folio), mapcount, mapping,80 folio->index + idx, pfn);81 if (folio_test_large(folio)) {82 pr_warn("head: order:%u mapcount:%d entire_mapcount:%d nr_pages_mapped:%d pincount:%d\n",83 folio_order(folio),84 folio_mapcount(folio),85 folio_entire_mapcount(folio),86 folio_nr_pages_mapped(folio),87 atomic_read(&folio->_pincount));88 }89 90#ifdef CONFIG_MEMCG91 if (folio->memcg_data)92 pr_warn("memcg:%lx\n", folio->memcg_data);93#endif94 if (folio_test_ksm(folio))95 type = "ksm ";96 else if (folio_test_anon(folio))97 type = "anon ";98 else if (mapping)99 dump_mapping(mapping);100 BUILD_BUG_ON(ARRAY_SIZE(pageflag_names) != __NR_PAGEFLAGS + 1);101 102 /*103 * Accessing the pageblock without the zone lock. It could change to104 * "isolate" again in the meantime, but since we are just dumping the105 * state for debugging, it should be fine to accept a bit of106 * inaccuracy here due to racing.107 */108 pr_warn("%sflags: %pGp%s\n", type, &folio->flags,109 is_migrate_cma_folio(folio, pfn) ? " CMA" : "");110 if (page_has_type(&folio->page))111 pr_warn("page_type: %x(%s)\n", folio->page.page_type >> 24,112 page_type_name(folio->page.page_type));113 114 print_hex_dump(KERN_WARNING, "raw: ", DUMP_PREFIX_NONE, 32,115 sizeof(unsigned long), page,116 sizeof(struct page), false);117 if (folio_test_large(folio))118 print_hex_dump(KERN_WARNING, "head: ", DUMP_PREFIX_NONE, 32,119 sizeof(unsigned long), folio,120 2 * sizeof(struct page), false);121}122 123static void __dump_page(const struct page *page)124{125 struct folio *foliop, folio;126 struct page precise;127 unsigned long pfn = page_to_pfn(page);128 unsigned long idx, nr_pages = 1;129 int loops = 5;130 131again:132 memcpy(&precise, page, sizeof(*page));133 foliop = page_folio(&precise);134 if (foliop == (struct folio *)&precise) {135 idx = 0;136 if (!folio_test_large(foliop))137 goto dump;138 foliop = (struct folio *)page;139 } else {140 idx = folio_page_idx(foliop, page);141 }142 143 if (idx < MAX_FOLIO_NR_PAGES) {144 memcpy(&folio, foliop, 2 * sizeof(struct page));145 nr_pages = folio_nr_pages(&folio);146 foliop = &folio;147 }148 149 if (idx > nr_pages) {150 if (loops-- > 0)151 goto again;152 pr_warn("page does not match folio\n");153 precise.compound_head &= ~1UL;154 foliop = (struct folio *)&precise;155 idx = 0;156 }157 158dump:159 __dump_folio(foliop, &precise, pfn, idx);160}161 162void dump_page(const struct page *page, const char *reason)163{164 if (PagePoisoned(page))165 pr_warn("page:%p is uninitialized and poisoned", page);166 else167 __dump_page(page);168 if (reason)169 pr_warn("page dumped because: %s\n", reason);170 dump_page_owner(page);171}172EXPORT_SYMBOL(dump_page);173 174#ifdef CONFIG_DEBUG_VM175 176void dump_vma(const struct vm_area_struct *vma)177{178 pr_emerg("vma %px start %px end %px mm %px\n"179 "prot %lx anon_vma %px vm_ops %px\n"180 "pgoff %lx file %px private_data %px\n"181 "flags: %#lx(%pGv)\n",182 vma, (void *)vma->vm_start, (void *)vma->vm_end, vma->vm_mm,183 (unsigned long)pgprot_val(vma->vm_page_prot),184 vma->anon_vma, vma->vm_ops, vma->vm_pgoff,185 vma->vm_file, vma->vm_private_data,186 vma->vm_flags, &vma->vm_flags);187}188EXPORT_SYMBOL(dump_vma);189 190void dump_mm(const struct mm_struct *mm)191{192 pr_emerg("mm %px task_size %lu\n"193 "mmap_base %lu mmap_legacy_base %lu\n"194 "pgd %px mm_users %d mm_count %d pgtables_bytes %lu map_count %d\n"195 "hiwater_rss %lx hiwater_vm %lx total_vm %lx locked_vm %lx\n"196 "pinned_vm %llx data_vm %lx exec_vm %lx stack_vm %lx\n"197 "start_code %lx end_code %lx start_data %lx end_data %lx\n"198 "start_brk %lx brk %lx start_stack %lx\n"199 "arg_start %lx arg_end %lx env_start %lx env_end %lx\n"200 "binfmt %px flags %lx\n"201#ifdef CONFIG_AIO202 "ioctx_table %px\n"203#endif204#ifdef CONFIG_MEMCG205 "owner %px "206#endif207 "exe_file %px\n"208#ifdef CONFIG_MMU_NOTIFIER209 "notifier_subscriptions %px\n"210#endif211#ifdef CONFIG_NUMA_BALANCING212 "numa_next_scan %lu numa_scan_offset %lu numa_scan_seq %d\n"213#endif214 "tlb_flush_pending %d\n"215 "def_flags: %#lx(%pGv)\n",216 217 mm, mm->task_size,218 mm->mmap_base, mm->mmap_legacy_base,219 mm->pgd, atomic_read(&mm->mm_users),220 atomic_read(&mm->mm_count),221 mm_pgtables_bytes(mm),222 mm->map_count,223 mm->hiwater_rss, mm->hiwater_vm, mm->total_vm, mm->locked_vm,224 (u64)atomic64_read(&mm->pinned_vm),225 mm->data_vm, mm->exec_vm, mm->stack_vm,226 mm->start_code, mm->end_code, mm->start_data, mm->end_data,227 mm->start_brk, mm->brk, mm->start_stack,228 mm->arg_start, mm->arg_end, mm->env_start, mm->env_end,229 mm->binfmt, mm->flags,230#ifdef CONFIG_AIO231 mm->ioctx_table,232#endif233#ifdef CONFIG_MEMCG234 mm->owner,235#endif236 mm->exe_file,237#ifdef CONFIG_MMU_NOTIFIER238 mm->notifier_subscriptions,239#endif240#ifdef CONFIG_NUMA_BALANCING241 mm->numa_next_scan, mm->numa_scan_offset, mm->numa_scan_seq,242#endif243 atomic_read(&mm->tlb_flush_pending),244 mm->def_flags, &mm->def_flags245 );246}247EXPORT_SYMBOL(dump_mm);248 249static bool page_init_poisoning __read_mostly = true;250 251static int __init setup_vm_debug(char *str)252{253 bool __page_init_poisoning = true;254 255 /*256 * Calling vm_debug with no arguments is equivalent to requesting257 * to enable all debugging options we can control.258 */259 if (*str++ != '=' || !*str)260 goto out;261 262 __page_init_poisoning = false;263 if (*str == '-')264 goto out;265 266 while (*str) {267 switch (tolower(*str)) {268 case'p':269 __page_init_poisoning = true;270 break;271 default:272 pr_err("vm_debug option '%c' unknown. skipped\n",273 *str);274 }275 276 str++;277 }278out:279 if (page_init_poisoning && !__page_init_poisoning)280 pr_warn("Page struct poisoning disabled by kernel command line option 'vm_debug'\n");281 282 page_init_poisoning = __page_init_poisoning;283 284 return 1;285}286__setup("vm_debug", setup_vm_debug);287 288void page_init_poison(struct page *page, size_t size)289{290 if (page_init_poisoning)291 memset(page, PAGE_POISON_PATTERN, size);292}293 294void vma_iter_dump_tree(const struct vma_iterator *vmi)295{296#if defined(CONFIG_DEBUG_VM_MAPLE_TREE)297 mas_dump(&vmi->mas);298 mt_dump(vmi->mas.tree, mt_dump_hex);299#endif /* CONFIG_DEBUG_VM_MAPLE_TREE */300}301 302#endif /* CONFIG_DEBUG_VM */303