1b2441318SGreg Kroah-Hartman // SPDX-License-Identifier: GPL-2.0
231c9afa6SSasha Levin /*
331c9afa6SSasha Levin * mm/debug.c
431c9afa6SSasha Levin *
531c9afa6SSasha Levin * mm/ specific debug routines.
631c9afa6SSasha Levin *
731c9afa6SSasha Levin */
831c9afa6SSasha Levin
982742a3aSSasha Levin #include <linux/kernel.h>
1082742a3aSSasha Levin #include <linux/mm.h>
11af658dcaSSteven Rostedt (Red Hat) #include <linux/trace_events.h>
1282742a3aSSasha Levin #include <linux/memcontrol.h>
13420adbe9SVlastimil Babka #include <trace/events/mmflags.h>
147cd12b4aSVlastimil Babka #include <linux/migrate.h>
154e462112SVlastimil Babka #include <linux/page_owner.h>
16f682a97aSAlexander Duyck #include <linux/ctype.h>
1782742a3aSSasha Levin
18edf14cdbSVlastimil Babka #include "internal.h"
198eb42beaSJohn Hubbard #include <trace/events/migrate.h>
208eb42beaSJohn Hubbard
218eb42beaSJohn Hubbard /*
228eb42beaSJohn Hubbard * Define EM() and EMe() so that MIGRATE_REASON from trace/events/migrate.h can
238eb42beaSJohn Hubbard * be used to populate migrate_reason_names[].
248eb42beaSJohn Hubbard */
258eb42beaSJohn Hubbard #undef EM
268eb42beaSJohn Hubbard #undef EMe
278eb42beaSJohn Hubbard #define EM(a, b) b,
288eb42beaSJohn Hubbard #define EMe(a, b) b
29edf14cdbSVlastimil Babka
309a2f45ffSAlexey Dobriyan const char *migrate_reason_names[MR_TYPES] = {
318eb42beaSJohn Hubbard MIGRATE_REASON
327cd12b4aSVlastimil Babka };
337cd12b4aSVlastimil Babka
34edf14cdbSVlastimil Babka const struct trace_print_flags pageflag_names[] = {
35edf14cdbSVlastimil Babka __def_pageflag_names,
36edf14cdbSVlastimil Babka {0, NULL}
37420adbe9SVlastimil Babka };
38420adbe9SVlastimil Babka
394c85c0beSHyeonggon Yoo const struct trace_print_flags pagetype_names[] = {
404c85c0beSHyeonggon Yoo __def_pagetype_names,
414c85c0beSHyeonggon Yoo {0, NULL}
424c85c0beSHyeonggon Yoo };
434c85c0beSHyeonggon Yoo
44edf14cdbSVlastimil Babka const struct trace_print_flags gfpflag_names[] = {
45edf14cdbSVlastimil Babka __def_gfpflag_names,
46edf14cdbSVlastimil Babka {0, NULL}
47edf14cdbSVlastimil Babka };
48edf14cdbSVlastimil Babka
49edf14cdbSVlastimil Babka const struct trace_print_flags vmaflag_names[] = {
50edf14cdbSVlastimil Babka __def_vmaflag_names,
51edf14cdbSVlastimil Babka {0, NULL}
5282742a3aSSasha Levin };
5382742a3aSSasha Levin
__dump_folio(struct folio * folio,struct page * page,unsigned long pfn,unsigned long idx)54fae7d834SMatthew Wilcox (Oracle) static void __dump_folio(struct folio *folio, struct page *page,
55fae7d834SMatthew Wilcox (Oracle) unsigned long pfn, unsigned long idx)
5682742a3aSSasha Levin {
57fae7d834SMatthew Wilcox (Oracle) struct address_space *mapping = folio_mapping(folio);
58*7441d349SDavid Hildenbrand int mapcount = atomic_read(&page->_mapcount);
595b57b8f2SVlastimil Babka char *type = "";
60fc36def9SPavel Tatashin
61*7441d349SDavid Hildenbrand mapcount = page_type_has_type(mapcount) ? 0 : mapcount + 1;
62fae7d834SMatthew Wilcox (Oracle) pr_warn("page: refcount:%d mapcount:%d mapping:%p index:%#lx pfn:%#lx\n",
63fae7d834SMatthew Wilcox (Oracle) folio_ref_count(folio), mapcount, mapping,
64fae7d834SMatthew Wilcox (Oracle) folio->index + idx, pfn);
65fae7d834SMatthew Wilcox (Oracle) if (folio_test_large(folio)) {
6605c5323bSDavid Hildenbrand pr_warn("head: order:%u mapcount:%d entire_mapcount:%d nr_pages_mapped:%d pincount:%d\n",
67fae7d834SMatthew Wilcox (Oracle) folio_order(folio),
6805c5323bSDavid Hildenbrand folio_mapcount(folio),
6991ec7f28SMatthew Wilcox (Oracle) folio_entire_mapcount(folio),
70eec20426SMatthew Wilcox (Oracle) folio_nr_pages_mapped(folio),
7194688e8eSMatthew Wilcox (Oracle) atomic_read(&folio->_pincount));
72452b557cSMatthew Wilcox (Oracle) }
7391f5345aSMatthew Wilcox (Oracle)
7491f5345aSMatthew Wilcox (Oracle) #ifdef CONFIG_MEMCG
75fae7d834SMatthew Wilcox (Oracle) if (folio->memcg_data)
76fae7d834SMatthew Wilcox (Oracle) pr_warn("memcg:%lx\n", folio->memcg_data);
7791f5345aSMatthew Wilcox (Oracle) #endif
78fae7d834SMatthew Wilcox (Oracle) if (folio_test_ksm(folio))
795b57b8f2SVlastimil Babka type = "ksm ";
80fae7d834SMatthew Wilcox (Oracle) else if (folio_test_anon(folio))
815b57b8f2SVlastimil Babka type = "anon ";
823e9d80a8SMatthew Wilcox (Oracle) else if (mapping)
833e9d80a8SMatthew Wilcox (Oracle) dump_mapping(mapping);
84edf14cdbSVlastimil Babka BUILD_BUG_ON(ARRAY_SIZE(pageflag_names) != __NR_PAGEFLAGS + 1);
85ff8e8116SVlastimil Babka
86fae7d834SMatthew Wilcox (Oracle) /*
87fae7d834SMatthew Wilcox (Oracle) * Accessing the pageblock without the zone lock. It could change to
88fae7d834SMatthew Wilcox (Oracle) * "isolate" again in the meantime, but since we are just dumping the
89fae7d834SMatthew Wilcox (Oracle) * state for debugging, it should be fine to accept a bit of
90fae7d834SMatthew Wilcox (Oracle) * inaccuracy here due to racing.
91fae7d834SMatthew Wilcox (Oracle) */
92fae7d834SMatthew Wilcox (Oracle) pr_warn("%sflags: %pGp%s\n", type, &folio->flags,
93fae7d834SMatthew Wilcox (Oracle) is_migrate_cma_folio(folio, pfn) ? " CMA" : "");
948f790d0cSMatthew Wilcox (Oracle) if (page_has_type(&folio->page))
95fae7d834SMatthew Wilcox (Oracle) pr_warn("page_type: %pGt\n", &folio->page.page_type);
96f2421a16SHyeonggon Yoo
97e0392cf7SMichal Hocko print_hex_dump(KERN_WARNING, "raw: ", DUMP_PREFIX_NONE, 32,
9846e8a3a0SVlastimil Babka sizeof(unsigned long), page,
9946e8a3a0SVlastimil Babka sizeof(struct page), false);
100fae7d834SMatthew Wilcox (Oracle) if (folio_test_large(folio))
1016197ab98SMatthew Wilcox (Oracle) print_hex_dump(KERN_WARNING, "head: ", DUMP_PREFIX_NONE, 32,
102fae7d834SMatthew Wilcox (Oracle) sizeof(unsigned long), folio,
103fae7d834SMatthew Wilcox (Oracle) 2 * sizeof(struct page), false);
104fae7d834SMatthew Wilcox (Oracle) }
105fae7d834SMatthew Wilcox (Oracle)
__dump_page(const struct page * page)106fae7d834SMatthew Wilcox (Oracle) static void __dump_page(const struct page *page)
107fae7d834SMatthew Wilcox (Oracle) {
108fae7d834SMatthew Wilcox (Oracle) struct folio *foliop, folio;
109fae7d834SMatthew Wilcox (Oracle) struct page precise;
110fae7d834SMatthew Wilcox (Oracle) unsigned long pfn = page_to_pfn(page);
111fae7d834SMatthew Wilcox (Oracle) unsigned long idx, nr_pages = 1;
112fae7d834SMatthew Wilcox (Oracle) int loops = 5;
113fae7d834SMatthew Wilcox (Oracle)
114fae7d834SMatthew Wilcox (Oracle) again:
115fae7d834SMatthew Wilcox (Oracle) memcpy(&precise, page, sizeof(*page));
116fae7d834SMatthew Wilcox (Oracle) foliop = page_folio(&precise);
117fae7d834SMatthew Wilcox (Oracle) if (foliop == (struct folio *)&precise) {
118fae7d834SMatthew Wilcox (Oracle) idx = 0;
119fae7d834SMatthew Wilcox (Oracle) if (!folio_test_large(foliop))
120fae7d834SMatthew Wilcox (Oracle) goto dump;
121fae7d834SMatthew Wilcox (Oracle) foliop = (struct folio *)page;
122fae7d834SMatthew Wilcox (Oracle) } else {
123fae7d834SMatthew Wilcox (Oracle) idx = folio_page_idx(foliop, page);
124fae7d834SMatthew Wilcox (Oracle) }
125fae7d834SMatthew Wilcox (Oracle)
126fae7d834SMatthew Wilcox (Oracle) if (idx < MAX_FOLIO_NR_PAGES) {
127fae7d834SMatthew Wilcox (Oracle) memcpy(&folio, foliop, 2 * sizeof(struct page));
128fae7d834SMatthew Wilcox (Oracle) nr_pages = folio_nr_pages(&folio);
129fae7d834SMatthew Wilcox (Oracle) foliop = &folio;
130fae7d834SMatthew Wilcox (Oracle) }
131fae7d834SMatthew Wilcox (Oracle)
132fae7d834SMatthew Wilcox (Oracle) if (idx > nr_pages) {
133fae7d834SMatthew Wilcox (Oracle) if (loops-- > 0)
134fae7d834SMatthew Wilcox (Oracle) goto again;
135fae7d834SMatthew Wilcox (Oracle) pr_warn("page does not match folio\n");
136fae7d834SMatthew Wilcox (Oracle) precise.compound_head &= ~1UL;
137fae7d834SMatthew Wilcox (Oracle) foliop = (struct folio *)&precise;
138fae7d834SMatthew Wilcox (Oracle) idx = 0;
139fae7d834SMatthew Wilcox (Oracle) }
140fae7d834SMatthew Wilcox (Oracle)
141fae7d834SMatthew Wilcox (Oracle) dump:
142fae7d834SMatthew Wilcox (Oracle) __dump_folio(foliop, &precise, pfn, idx);
14382742a3aSSasha Levin }
14482742a3aSSasha Levin
dump_page(const struct page * page,const char * reason)145b3a32033SMatthew Wilcox (Oracle) void dump_page(const struct page *page, const char *reason)
14682742a3aSSasha Levin {
147be7c701fSMatthew Wilcox (Oracle) if (PagePoisoned(page))
148be7c701fSMatthew Wilcox (Oracle) pr_warn("page:%p is uninitialized and poisoned", page);
149be7c701fSMatthew Wilcox (Oracle) else
150be7c701fSMatthew Wilcox (Oracle) __dump_page(page);
151be7c701fSMatthew Wilcox (Oracle) if (reason)
152be7c701fSMatthew Wilcox (Oracle) pr_warn("page dumped because: %s\n", reason);
1534e462112SVlastimil Babka dump_page_owner(page);
15482742a3aSSasha Levin }
15582742a3aSSasha Levin EXPORT_SYMBOL(dump_page);
15682742a3aSSasha Levin
15782742a3aSSasha Levin #ifdef CONFIG_DEBUG_VM
15882742a3aSSasha Levin
dump_vma(const struct vm_area_struct * vma)15982742a3aSSasha Levin void dump_vma(const struct vm_area_struct *vma)
16082742a3aSSasha Levin {
161763ecb03SLiam R. Howlett pr_emerg("vma %px start %px end %px mm %px\n"
162152a2d19SMatthew Wilcox "prot %lx anon_vma %px vm_ops %px\n"
163152a2d19SMatthew Wilcox "pgoff %lx file %px private_data %px\n"
164b8eceeb9SVlastimil Babka "flags: %#lx(%pGv)\n",
165763ecb03SLiam R. Howlett vma, (void *)vma->vm_start, (void *)vma->vm_end, vma->vm_mm,
16682742a3aSSasha Levin (unsigned long)pgprot_val(vma->vm_page_prot),
16782742a3aSSasha Levin vma->anon_vma, vma->vm_ops, vma->vm_pgoff,
168b8eceeb9SVlastimil Babka vma->vm_file, vma->vm_private_data,
169b8eceeb9SVlastimil Babka vma->vm_flags, &vma->vm_flags);
17082742a3aSSasha Levin }
17182742a3aSSasha Levin EXPORT_SYMBOL(dump_vma);
17282742a3aSSasha Levin
dump_mm(const struct mm_struct * mm)17331c9afa6SSasha Levin void dump_mm(const struct mm_struct *mm)
17431c9afa6SSasha Levin {
175763ecb03SLiam R. Howlett pr_emerg("mm %px task_size %lu\n"
176763ecb03SLiam R. Howlett "mmap_base %lu mmap_legacy_base %lu\n"
177152a2d19SMatthew Wilcox "pgd %px mm_users %d mm_count %d pgtables_bytes %lu map_count %d\n"
17831c9afa6SSasha Levin "hiwater_rss %lx hiwater_vm %lx total_vm %lx locked_vm %lx\n"
17970f8a3caSDavidlohr Bueso "pinned_vm %llx data_vm %lx exec_vm %lx stack_vm %lx\n"
18031c9afa6SSasha Levin "start_code %lx end_code %lx start_data %lx end_data %lx\n"
18131c9afa6SSasha Levin "start_brk %lx brk %lx start_stack %lx\n"
18231c9afa6SSasha Levin "arg_start %lx arg_end %lx env_start %lx env_end %lx\n"
1830258b5fdSEric W. Biederman "binfmt %px flags %lx\n"
18431c9afa6SSasha Levin #ifdef CONFIG_AIO
185152a2d19SMatthew Wilcox "ioctx_table %px\n"
18631c9afa6SSasha Levin #endif
18731c9afa6SSasha Levin #ifdef CONFIG_MEMCG
188152a2d19SMatthew Wilcox "owner %px "
18931c9afa6SSasha Levin #endif
190152a2d19SMatthew Wilcox "exe_file %px\n"
19131c9afa6SSasha Levin #ifdef CONFIG_MMU_NOTIFIER
192984cfe4eSJason Gunthorpe "notifier_subscriptions %px\n"
19331c9afa6SSasha Levin #endif
19431c9afa6SSasha Levin #ifdef CONFIG_NUMA_BALANCING
19531c9afa6SSasha Levin "numa_next_scan %lu numa_scan_offset %lu numa_scan_seq %d\n"
19631c9afa6SSasha Levin #endif
19731c9afa6SSasha Levin "tlb_flush_pending %d\n"
198b8eceeb9SVlastimil Babka "def_flags: %#lx(%pGv)\n",
19931c9afa6SSasha Levin
200763ecb03SLiam R. Howlett mm, mm->task_size,
201763ecb03SLiam R. Howlett mm->mmap_base, mm->mmap_legacy_base,
20231c9afa6SSasha Levin mm->pgd, atomic_read(&mm->mm_users),
20331c9afa6SSasha Levin atomic_read(&mm->mm_count),
204af5b0f6aSKirill A. Shutemov mm_pgtables_bytes(mm),
20531c9afa6SSasha Levin mm->map_count,
20631c9afa6SSasha Levin mm->hiwater_rss, mm->hiwater_vm, mm->total_vm, mm->locked_vm,
20744dc1b1fSQian Cai (u64)atomic64_read(&mm->pinned_vm),
20870f8a3caSDavidlohr Bueso mm->data_vm, mm->exec_vm, mm->stack_vm,
20931c9afa6SSasha Levin mm->start_code, mm->end_code, mm->start_data, mm->end_data,
21031c9afa6SSasha Levin mm->start_brk, mm->brk, mm->start_stack,
21131c9afa6SSasha Levin mm->arg_start, mm->arg_end, mm->env_start, mm->env_end,
2120258b5fdSEric W. Biederman mm->binfmt, mm->flags,
21331c9afa6SSasha Levin #ifdef CONFIG_AIO
21431c9afa6SSasha Levin mm->ioctx_table,
21531c9afa6SSasha Levin #endif
21631c9afa6SSasha Levin #ifdef CONFIG_MEMCG
21731c9afa6SSasha Levin mm->owner,
21831c9afa6SSasha Levin #endif
21931c9afa6SSasha Levin mm->exe_file,
22031c9afa6SSasha Levin #ifdef CONFIG_MMU_NOTIFIER
221984cfe4eSJason Gunthorpe mm->notifier_subscriptions,
22231c9afa6SSasha Levin #endif
22331c9afa6SSasha Levin #ifdef CONFIG_NUMA_BALANCING
22431c9afa6SSasha Levin mm->numa_next_scan, mm->numa_scan_offset, mm->numa_scan_seq,
22531c9afa6SSasha Levin #endif
22616af97dcSNadav Amit atomic_read(&mm->tlb_flush_pending),
227b8eceeb9SVlastimil Babka mm->def_flags, &mm->def_flags
22831c9afa6SSasha Levin );
22931c9afa6SSasha Levin }
230c2fdc235SSuren Baghdasaryan EXPORT_SYMBOL(dump_mm);
23131c9afa6SSasha Levin
232f682a97aSAlexander Duyck static bool page_init_poisoning __read_mostly = true;
233f682a97aSAlexander Duyck
setup_vm_debug(char * str)234f682a97aSAlexander Duyck static int __init setup_vm_debug(char *str)
235f682a97aSAlexander Duyck {
236f682a97aSAlexander Duyck bool __page_init_poisoning = true;
237f682a97aSAlexander Duyck
238f682a97aSAlexander Duyck /*
239f682a97aSAlexander Duyck * Calling vm_debug with no arguments is equivalent to requesting
240f682a97aSAlexander Duyck * to enable all debugging options we can control.
241f682a97aSAlexander Duyck */
242f682a97aSAlexander Duyck if (*str++ != '=' || !*str)
243f682a97aSAlexander Duyck goto out;
244f682a97aSAlexander Duyck
245f682a97aSAlexander Duyck __page_init_poisoning = false;
246f682a97aSAlexander Duyck if (*str == '-')
247f682a97aSAlexander Duyck goto out;
248f682a97aSAlexander Duyck
249f682a97aSAlexander Duyck while (*str) {
250f682a97aSAlexander Duyck switch (tolower(*str)) {
251f682a97aSAlexander Duyck case'p':
252f682a97aSAlexander Duyck __page_init_poisoning = true;
253f682a97aSAlexander Duyck break;
254f682a97aSAlexander Duyck default:
255f682a97aSAlexander Duyck pr_err("vm_debug option '%c' unknown. skipped\n",
256f682a97aSAlexander Duyck *str);
257f682a97aSAlexander Duyck }
258f682a97aSAlexander Duyck
259f682a97aSAlexander Duyck str++;
260f682a97aSAlexander Duyck }
261f682a97aSAlexander Duyck out:
262f682a97aSAlexander Duyck if (page_init_poisoning && !__page_init_poisoning)
263f682a97aSAlexander Duyck pr_warn("Page struct poisoning disabled by kernel command line option 'vm_debug'\n");
264f682a97aSAlexander Duyck
265f682a97aSAlexander Duyck page_init_poisoning = __page_init_poisoning;
266f682a97aSAlexander Duyck
267f682a97aSAlexander Duyck return 1;
268f682a97aSAlexander Duyck }
269f682a97aSAlexander Duyck __setup("vm_debug", setup_vm_debug);
270f682a97aSAlexander Duyck
page_init_poison(struct page * page,size_t size)271f682a97aSAlexander Duyck void page_init_poison(struct page *page, size_t size)
272f682a97aSAlexander Duyck {
273f682a97aSAlexander Duyck if (page_init_poisoning)
274f682a97aSAlexander Duyck memset(page, PAGE_POISON_PATTERN, size);
275f682a97aSAlexander Duyck }
276b50e195fSLiam R. Howlett
vma_iter_dump_tree(const struct vma_iterator * vmi)277b50e195fSLiam R. Howlett void vma_iter_dump_tree(const struct vma_iterator *vmi)
278b50e195fSLiam R. Howlett {
279b50e195fSLiam R. Howlett #if defined(CONFIG_DEBUG_VM_MAPLE_TREE)
280b50e195fSLiam R. Howlett mas_dump(&vmi->mas);
281b50e195fSLiam R. Howlett mt_dump(vmi->mas.tree, mt_dump_hex);
282b50e195fSLiam R. Howlett #endif /* CONFIG_DEBUG_VM_MAPLE_TREE */
283b50e195fSLiam R. Howlett }
284b50e195fSLiam R. Howlett
28582742a3aSSasha Levin #endif /* CONFIG_DEBUG_VM */
286