1 // SPDX-License-Identifier: GPL-2.0
5 * mm/ specific debug routines.
9 #include <linux/kernel.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>
19 #include <trace/events/migrate.h>
22 * Define EM() and EMe() so that MIGRATE_REASON from trace/events/migrate.h can
23 * be used to populate migrate_reason_names[].
30 const char *migrate_reason_names[MR_TYPES] = {
34 const struct trace_print_flags pageflag_names[] = {
39 const struct trace_print_flags pagetype_names[] = {
44 const struct trace_print_flags gfpflag_names[] = {
49 const struct trace_print_flags vmaflag_names[] = {
54 static void __dump_folio(struct folio *folio, struct page *page,
55 unsigned long pfn, unsigned long idx)
57 struct address_space *mapping = folio_mapping(folio);
62 * page->_mapcount space in struct page is used by slab pages to
63 * encode own info, and we must avoid calling page_folio() again.
65 if (!folio_test_slab(folio)) {
66 mapcount = atomic_read(&page->_mapcount) + 1;
67 if (folio_test_large(folio))
68 mapcount += folio_entire_mapcount(folio);
71 pr_warn("page: refcount:%d mapcount:%d mapping:%p index:%#lx pfn:%#lx\n",
72 folio_ref_count(folio), mapcount, mapping,
73 folio->index + idx, pfn);
74 if (folio_test_large(folio)) {
75 pr_warn("head: order:%u entire_mapcount:%d nr_pages_mapped:%d pincount:%d\n",
77 folio_entire_mapcount(folio),
78 folio_nr_pages_mapped(folio),
79 atomic_read(&folio->_pincount));
83 if (folio->memcg_data)
84 pr_warn("memcg:%lx\n", folio->memcg_data);
86 if (folio_test_ksm(folio))
88 else if (folio_test_anon(folio))
91 dump_mapping(mapping);
92 BUILD_BUG_ON(ARRAY_SIZE(pageflag_names) != __NR_PAGEFLAGS + 1);
95 * Accessing the pageblock without the zone lock. It could change to
96 * "isolate" again in the meantime, but since we are just dumping the
97 * state for debugging, it should be fine to accept a bit of
98 * inaccuracy here due to racing.
100 pr_warn("%sflags: %pGp%s\n", type, &folio->flags,
101 is_migrate_cma_folio(folio, pfn) ? " CMA" : "");
102 pr_warn("page_type: %pGt\n", &folio->page.page_type);
104 print_hex_dump(KERN_WARNING, "raw: ", DUMP_PREFIX_NONE, 32,
105 sizeof(unsigned long), page,
106 sizeof(struct page), false);
107 if (folio_test_large(folio))
108 print_hex_dump(KERN_WARNING, "head: ", DUMP_PREFIX_NONE, 32,
109 sizeof(unsigned long), folio,
110 2 * sizeof(struct page), false);
113 static void __dump_page(const struct page *page)
115 struct folio *foliop, folio;
117 unsigned long pfn = page_to_pfn(page);
118 unsigned long idx, nr_pages = 1;
122 memcpy(&precise, page, sizeof(*page));
123 foliop = page_folio(&precise);
124 if (foliop == (struct folio *)&precise) {
126 if (!folio_test_large(foliop))
128 foliop = (struct folio *)page;
130 idx = folio_page_idx(foliop, page);
133 if (idx < MAX_FOLIO_NR_PAGES) {
134 memcpy(&folio, foliop, 2 * sizeof(struct page));
135 nr_pages = folio_nr_pages(&folio);
139 if (idx > nr_pages) {
142 pr_warn("page does not match folio\n");
143 precise.compound_head &= ~1UL;
144 foliop = (struct folio *)&precise;
149 __dump_folio(foliop, &precise, pfn, idx);
152 void dump_page(const struct page *page, const char *reason)
154 if (PagePoisoned(page))
155 pr_warn("page:%p is uninitialized and poisoned", page);
159 pr_warn("page dumped because: %s\n", reason);
160 dump_page_owner(page);
162 EXPORT_SYMBOL(dump_page);
164 #ifdef CONFIG_DEBUG_VM
166 void dump_vma(const struct vm_area_struct *vma)
168 pr_emerg("vma %px start %px end %px mm %px\n"
169 "prot %lx anon_vma %px vm_ops %px\n"
170 "pgoff %lx file %px private_data %px\n"
171 "flags: %#lx(%pGv)\n",
172 vma, (void *)vma->vm_start, (void *)vma->vm_end, vma->vm_mm,
173 (unsigned long)pgprot_val(vma->vm_page_prot),
174 vma->anon_vma, vma->vm_ops, vma->vm_pgoff,
175 vma->vm_file, vma->vm_private_data,
176 vma->vm_flags, &vma->vm_flags);
178 EXPORT_SYMBOL(dump_vma);
180 void dump_mm(const struct mm_struct *mm)
182 pr_emerg("mm %px task_size %lu\n"
184 "get_unmapped_area %px\n"
186 "mmap_base %lu mmap_legacy_base %lu\n"
187 "pgd %px mm_users %d mm_count %d pgtables_bytes %lu map_count %d\n"
188 "hiwater_rss %lx hiwater_vm %lx total_vm %lx locked_vm %lx\n"
189 "pinned_vm %llx data_vm %lx exec_vm %lx stack_vm %lx\n"
190 "start_code %lx end_code %lx start_data %lx end_data %lx\n"
191 "start_brk %lx brk %lx start_stack %lx\n"
192 "arg_start %lx arg_end %lx env_start %lx env_end %lx\n"
193 "binfmt %px flags %lx\n"
201 #ifdef CONFIG_MMU_NOTIFIER
202 "notifier_subscriptions %px\n"
204 #ifdef CONFIG_NUMA_BALANCING
205 "numa_next_scan %lu numa_scan_offset %lu numa_scan_seq %d\n"
207 "tlb_flush_pending %d\n"
208 "def_flags: %#lx(%pGv)\n",
212 mm->get_unmapped_area,
214 mm->mmap_base, mm->mmap_legacy_base,
215 mm->pgd, atomic_read(&mm->mm_users),
216 atomic_read(&mm->mm_count),
217 mm_pgtables_bytes(mm),
219 mm->hiwater_rss, mm->hiwater_vm, mm->total_vm, mm->locked_vm,
220 (u64)atomic64_read(&mm->pinned_vm),
221 mm->data_vm, mm->exec_vm, mm->stack_vm,
222 mm->start_code, mm->end_code, mm->start_data, mm->end_data,
223 mm->start_brk, mm->brk, mm->start_stack,
224 mm->arg_start, mm->arg_end, mm->env_start, mm->env_end,
225 mm->binfmt, mm->flags,
233 #ifdef CONFIG_MMU_NOTIFIER
234 mm->notifier_subscriptions,
236 #ifdef CONFIG_NUMA_BALANCING
237 mm->numa_next_scan, mm->numa_scan_offset, mm->numa_scan_seq,
239 atomic_read(&mm->tlb_flush_pending),
240 mm->def_flags, &mm->def_flags
243 EXPORT_SYMBOL(dump_mm);
245 static bool page_init_poisoning __read_mostly = true;
247 static int __init setup_vm_debug(char *str)
249 bool __page_init_poisoning = true;
252 * Calling vm_debug with no arguments is equivalent to requesting
253 * to enable all debugging options we can control.
255 if (*str++ != '=' || !*str)
258 __page_init_poisoning = false;
263 switch (tolower(*str)) {
265 __page_init_poisoning = true;
268 pr_err("vm_debug option '%c' unknown. skipped\n",
275 if (page_init_poisoning && !__page_init_poisoning)
276 pr_warn("Page struct poisoning disabled by kernel command line option 'vm_debug'\n");
278 page_init_poisoning = __page_init_poisoning;
282 __setup("vm_debug", setup_vm_debug);
284 void page_init_poison(struct page *page, size_t size)
286 if (page_init_poisoning)
287 memset(page, PAGE_POISON_PATTERN, size);
290 void vma_iter_dump_tree(const struct vma_iterator *vmi)
292 #if defined(CONFIG_DEBUG_VM_MAPLE_TREE)
294 mt_dump(vmi->mas.tree, mt_dump_hex);
295 #endif /* CONFIG_DEBUG_VM_MAPLE_TREE */
298 #endif /* CONFIG_DEBUG_VM */