1 // SPDX-License-Identifier: GPL-2.0 1 // SPDX-License-Identifier: GPL-2.0
2 /* 2 /*
3 * mm/debug.c 3 * mm/debug.c
4 * 4 *
5 * mm/ specific debug routines. 5 * mm/ specific debug routines.
6 * 6 *
7 */ 7 */
8 8
9 #include <linux/kernel.h> 9 #include <linux/kernel.h>
10 #include <linux/mm.h> 10 #include <linux/mm.h>
11 #include <linux/trace_events.h> 11 #include <linux/trace_events.h>
12 #include <linux/memcontrol.h> 12 #include <linux/memcontrol.h>
13 #include <trace/events/mmflags.h> 13 #include <trace/events/mmflags.h>
14 #include <linux/migrate.h> 14 #include <linux/migrate.h>
15 #include <linux/page_owner.h> 15 #include <linux/page_owner.h>
16 #include <linux/ctype.h> 16 #include <linux/ctype.h>
17 17
18 #include "internal.h" 18 #include "internal.h"
19 #include <trace/events/migrate.h> <<
20 <<
21 /* <<
22 * Define EM() and EMe() so that MIGRATE_REASO <<
23 * be used to populate migrate_reason_names[]. <<
24 */ <<
25 #undef EM <<
26 #undef EMe <<
27 #define EM(a, b) b, <<
28 #define EMe(a, b) b <<
29 19
30 const char *migrate_reason_names[MR_TYPES] = { 20 const char *migrate_reason_names[MR_TYPES] = {
31 MIGRATE_REASON !! 21 "compaction",
>> 22 "memory_failure",
>> 23 "memory_hotplug",
>> 24 "syscall_or_cpuset",
>> 25 "mempolicy_mbind",
>> 26 "numa_misplaced",
>> 27 "cma",
32 }; 28 };
33 29
34 const struct trace_print_flags pageflag_names[ 30 const struct trace_print_flags pageflag_names[] = {
35 __def_pageflag_names, 31 __def_pageflag_names,
36 {0, NULL} 32 {0, NULL}
37 }; 33 };
38 34
39 const struct trace_print_flags gfpflag_names[] 35 const struct trace_print_flags gfpflag_names[] = {
40 __def_gfpflag_names, 36 __def_gfpflag_names,
41 {0, NULL} 37 {0, NULL}
42 }; 38 };
43 39
44 const struct trace_print_flags vmaflag_names[] 40 const struct trace_print_flags vmaflag_names[] = {
45 __def_vmaflag_names, 41 __def_vmaflag_names,
46 {0, NULL} 42 {0, NULL}
47 }; 43 };
48 44
49 #define DEF_PAGETYPE_NAME(_name) [PGTY_##_name !! 45 void __dump_page(struct page *page, const char *reason)
50 <<
51 static 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 <<
61 static const char *page_type_name(unsigned int <<
62 { 46 {
63 unsigned i = (page_type >> 24) - 0xf0; !! 47 struct address_space *mapping;
64 !! 48 bool page_poisoned = PagePoisoned(page);
65 if (i >= ARRAY_SIZE(page_type_names)) !! 49 /*
66 return "unknown"; !! 50 * Accessing the pageblock without the zone lock. It could change to
67 return page_type_names[i]; !! 51 * "isolate" again in the meantime, but since we are just dumping the
68 } !! 52 * state for debugging, it should be fine to accept a bit of
69 !! 53 * inaccuracy here due to racing.
70 static void __dump_folio(struct folio *folio, !! 54 */
71 unsigned long pfn, unsigned lo !! 55 bool page_cma = is_migrate_cma_page(page);
72 { !! 56 int mapcount;
73 struct address_space *mapping = folio_ <<
74 int mapcount = atomic_read(&page->_map <<
75 char *type = ""; 57 char *type = "";
76 58
77 mapcount = page_mapcount_is_type(mapco !! 59 /*
78 pr_warn("page: refcount:%d mapcount:%d !! 60 * If struct page is poisoned don't access Page*() functions as that
79 folio_ref_count(folio) !! 61 * leads to recursive loop. Page*() check for poisoned pages, and calls
80 folio->index + idx, pf !! 62 * dump_page() when detected.
81 if (folio_test_large(folio)) { !! 63 */
82 pr_warn("head: order:%u mapcou !! 64 if (page_poisoned) {
83 folio_order(fo !! 65 pr_warn("page:%px is uninitialized and poisoned", page);
84 folio_mapcount !! 66 goto hex_only;
85 folio_entire_m <<
86 folio_nr_pages <<
87 atomic_read(&f <<
88 } 67 }
89 68
90 #ifdef CONFIG_MEMCG !! 69 mapping = page_mapping(page);
91 if (folio->memcg_data) !! 70
92 pr_warn("memcg:%lx\n", folio-> !! 71 /*
93 #endif !! 72 * Avoid VM_BUG_ON() in page_mapcount().
94 if (folio_test_ksm(folio)) !! 73 * page->_mapcount space in struct page is used by sl[aou]b pages to
>> 74 * encode own info.
>> 75 */
>> 76 mapcount = PageSlab(page) ? 0 : page_mapcount(page);
>> 77
>> 78 if (PageCompound(page))
>> 79 pr_warn("page:%px refcount:%d mapcount:%d mapping:%px "
>> 80 "index:%#lx compound_mapcount: %d\n",
>> 81 page, page_ref_count(page), mapcount,
>> 82 page->mapping, page_to_pgoff(page),
>> 83 compound_mapcount(page));
>> 84 else
>> 85 pr_warn("page:%px refcount:%d mapcount:%d mapping:%px index:%#lx\n",
>> 86 page, page_ref_count(page), mapcount,
>> 87 page->mapping, page_to_pgoff(page));
>> 88 if (PageKsm(page))
95 type = "ksm "; 89 type = "ksm ";
96 else if (folio_test_anon(folio)) !! 90 else if (PageAnon(page))
97 type = "anon "; 91 type = "anon ";
98 else if (mapping) !! 92 else if (mapping) {
99 dump_mapping(mapping); !! 93 if (mapping->host && mapping->host->i_dentry.first) {
>> 94 struct dentry *dentry;
>> 95 dentry = container_of(mapping->host->i_dentry.first, struct dentry, d_u.d_alias);
>> 96 pr_warn("%ps name:\"%pd\"\n", mapping->a_ops, dentry);
>> 97 } else
>> 98 pr_warn("%ps\n", mapping->a_ops);
>> 99 }
100 BUILD_BUG_ON(ARRAY_SIZE(pageflag_names 100 BUILD_BUG_ON(ARRAY_SIZE(pageflag_names) != __NR_PAGEFLAGS + 1);
101 101
102 /* !! 102 pr_warn("%sflags: %#lx(%pGp)%s\n", type, page->flags, &page->flags,
103 * Accessing the pageblock without the !! 103 page_cma ? " CMA" : "");
104 * "isolate" again in the meantime, bu <<
105 * state for debugging, it should be f <<
106 * inaccuracy here due to racing. <<
107 */ <<
108 pr_warn("%sflags: %pGp%s\n", type, &fo <<
109 is_migrate_cma_folio(folio, pf <<
110 if (page_has_type(&folio->page)) <<
111 pr_warn("page_type: %x(%s)\n", <<
112 page_type_name <<
113 104
>> 105 hex_only:
114 print_hex_dump(KERN_WARNING, "raw: ", 106 print_hex_dump(KERN_WARNING, "raw: ", DUMP_PREFIX_NONE, 32,
115 sizeof(unsigned long), 107 sizeof(unsigned long), page,
116 sizeof(struct page), f 108 sizeof(struct page), false);
117 if (folio_test_large(folio)) <<
118 print_hex_dump(KERN_WARNING, " <<
119 sizeof(unsigned long), <<
120 2 * sizeof(struct page <<
121 } <<
122 109
123 static void __dump_page(const struct page *pag !! 110 if (reason)
124 { !! 111 pr_warn("page dumped because: %s\n", reason);
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 <<
131 again: <<
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, p <<
141 } <<
142 <<
143 if (idx < MAX_FOLIO_NR_PAGES) { <<
144 memcpy(&folio, foliop, 2 * siz <<
145 nr_pages = folio_nr_pages(&fol <<
146 foliop = &folio; <<
147 } <<
148 <<
149 if (idx > nr_pages) { <<
150 if (loops-- > 0) <<
151 goto again; <<
152 pr_warn("page does not match f <<
153 precise.compound_head &= ~1UL; <<
154 foliop = (struct folio *)&prec <<
155 idx = 0; <<
156 } <<
157 112
158 dump: !! 113 #ifdef CONFIG_MEMCG
159 __dump_folio(foliop, &precise, pfn, id !! 114 if (!page_poisoned && page->mem_cgroup)
>> 115 pr_warn("page->mem_cgroup:%px\n", page->mem_cgroup);
>> 116 #endif
160 } 117 }
161 118
162 void dump_page(const struct page *page, const !! 119 void dump_page(struct page *page, const char *reason)
163 { 120 {
164 if (PagePoisoned(page)) !! 121 __dump_page(page, reason);
165 pr_warn("page:%p is uninitiali <<
166 else <<
167 __dump_page(page); <<
168 if (reason) <<
169 pr_warn("page dumped because: <<
170 dump_page_owner(page); 122 dump_page_owner(page);
171 } 123 }
172 EXPORT_SYMBOL(dump_page); 124 EXPORT_SYMBOL(dump_page);
173 125
174 #ifdef CONFIG_DEBUG_VM 126 #ifdef CONFIG_DEBUG_VM
175 127
176 void dump_vma(const struct vm_area_struct *vma 128 void dump_vma(const struct vm_area_struct *vma)
177 { 129 {
178 pr_emerg("vma %px start %px end %px mm !! 130 pr_emerg("vma %px start %px end %px\n"
>> 131 "next %px prev %px mm %px\n"
179 "prot %lx anon_vma %px vm_ops 132 "prot %lx anon_vma %px vm_ops %px\n"
180 "pgoff %lx file %px private_da 133 "pgoff %lx file %px private_data %px\n"
181 "flags: %#lx(%pGv)\n", 134 "flags: %#lx(%pGv)\n",
182 vma, (void *)vma->vm_start, (v !! 135 vma, (void *)vma->vm_start, (void *)vma->vm_end, vma->vm_next,
>> 136 vma->vm_prev, vma->vm_mm,
183 (unsigned long)pgprot_val(vma- 137 (unsigned long)pgprot_val(vma->vm_page_prot),
184 vma->anon_vma, vma->vm_ops, vm 138 vma->anon_vma, vma->vm_ops, vma->vm_pgoff,
185 vma->vm_file, vma->vm_private_ 139 vma->vm_file, vma->vm_private_data,
186 vma->vm_flags, &vma->vm_flags) 140 vma->vm_flags, &vma->vm_flags);
187 } 141 }
188 EXPORT_SYMBOL(dump_vma); 142 EXPORT_SYMBOL(dump_vma);
189 143
190 void dump_mm(const struct mm_struct *mm) 144 void dump_mm(const struct mm_struct *mm)
191 { 145 {
192 pr_emerg("mm %px task_size %lu\n" !! 146 pr_emerg("mm %px mmap %px seqnum %llu task_size %lu\n"
193 "mmap_base %lu mmap_legacy_bas !! 147 #ifdef CONFIG_MMU
>> 148 "get_unmapped_area %px\n"
>> 149 #endif
>> 150 "mmap_base %lu mmap_legacy_base %lu highest_vm_end %lu\n"
194 "pgd %px mm_users %d mm_count 151 "pgd %px mm_users %d mm_count %d pgtables_bytes %lu map_count %d\n"
195 "hiwater_rss %lx hiwater_vm %l 152 "hiwater_rss %lx hiwater_vm %lx total_vm %lx locked_vm %lx\n"
196 "pinned_vm %llx data_vm %lx ex 153 "pinned_vm %llx data_vm %lx exec_vm %lx stack_vm %lx\n"
197 "start_code %lx end_code %lx s 154 "start_code %lx end_code %lx start_data %lx end_data %lx\n"
198 "start_brk %lx brk %lx start_s 155 "start_brk %lx brk %lx start_stack %lx\n"
199 "arg_start %lx arg_end %lx env 156 "arg_start %lx arg_end %lx env_start %lx env_end %lx\n"
200 "binfmt %px flags %lx\n" !! 157 "binfmt %px flags %lx core_state %px\n"
201 #ifdef CONFIG_AIO 158 #ifdef CONFIG_AIO
202 "ioctx_table %px\n" 159 "ioctx_table %px\n"
203 #endif 160 #endif
204 #ifdef CONFIG_MEMCG 161 #ifdef CONFIG_MEMCG
205 "owner %px " 162 "owner %px "
206 #endif 163 #endif
207 "exe_file %px\n" 164 "exe_file %px\n"
208 #ifdef CONFIG_MMU_NOTIFIER 165 #ifdef CONFIG_MMU_NOTIFIER
209 "notifier_subscriptions %px\n" 166 "notifier_subscriptions %px\n"
210 #endif 167 #endif
211 #ifdef CONFIG_NUMA_BALANCING 168 #ifdef CONFIG_NUMA_BALANCING
212 "numa_next_scan %lu numa_scan_ 169 "numa_next_scan %lu numa_scan_offset %lu numa_scan_seq %d\n"
213 #endif 170 #endif
214 "tlb_flush_pending %d\n" 171 "tlb_flush_pending %d\n"
215 "def_flags: %#lx(%pGv)\n", 172 "def_flags: %#lx(%pGv)\n",
216 173
217 mm, mm->task_size, !! 174 mm, mm->mmap, (long long) mm->vmacache_seqnum, mm->task_size,
218 mm->mmap_base, mm->mmap_legacy !! 175 #ifdef CONFIG_MMU
>> 176 mm->get_unmapped_area,
>> 177 #endif
>> 178 mm->mmap_base, mm->mmap_legacy_base, mm->highest_vm_end,
219 mm->pgd, atomic_read(&mm->mm_u 179 mm->pgd, atomic_read(&mm->mm_users),
220 atomic_read(&mm->mm_count), 180 atomic_read(&mm->mm_count),
221 mm_pgtables_bytes(mm), 181 mm_pgtables_bytes(mm),
222 mm->map_count, 182 mm->map_count,
223 mm->hiwater_rss, mm->hiwater_v 183 mm->hiwater_rss, mm->hiwater_vm, mm->total_vm, mm->locked_vm,
224 (u64)atomic64_read(&mm->pinned 184 (u64)atomic64_read(&mm->pinned_vm),
225 mm->data_vm, mm->exec_vm, mm-> 185 mm->data_vm, mm->exec_vm, mm->stack_vm,
226 mm->start_code, mm->end_code, 186 mm->start_code, mm->end_code, mm->start_data, mm->end_data,
227 mm->start_brk, mm->brk, mm->st 187 mm->start_brk, mm->brk, mm->start_stack,
228 mm->arg_start, mm->arg_end, mm 188 mm->arg_start, mm->arg_end, mm->env_start, mm->env_end,
229 mm->binfmt, mm->flags, !! 189 mm->binfmt, mm->flags, mm->core_state,
230 #ifdef CONFIG_AIO 190 #ifdef CONFIG_AIO
231 mm->ioctx_table, 191 mm->ioctx_table,
232 #endif 192 #endif
233 #ifdef CONFIG_MEMCG 193 #ifdef CONFIG_MEMCG
234 mm->owner, 194 mm->owner,
235 #endif 195 #endif
236 mm->exe_file, 196 mm->exe_file,
237 #ifdef CONFIG_MMU_NOTIFIER 197 #ifdef CONFIG_MMU_NOTIFIER
238 mm->notifier_subscriptions, 198 mm->notifier_subscriptions,
239 #endif 199 #endif
240 #ifdef CONFIG_NUMA_BALANCING 200 #ifdef CONFIG_NUMA_BALANCING
241 mm->numa_next_scan, mm->numa_s 201 mm->numa_next_scan, mm->numa_scan_offset, mm->numa_scan_seq,
242 #endif 202 #endif
243 atomic_read(&mm->tlb_flush_pen 203 atomic_read(&mm->tlb_flush_pending),
244 mm->def_flags, &mm->def_flags 204 mm->def_flags, &mm->def_flags
245 ); 205 );
246 } 206 }
247 EXPORT_SYMBOL(dump_mm); <<
248 207
249 static bool page_init_poisoning __read_mostly 208 static bool page_init_poisoning __read_mostly = true;
250 209
251 static int __init setup_vm_debug(char *str) 210 static int __init setup_vm_debug(char *str)
252 { 211 {
253 bool __page_init_poisoning = true; 212 bool __page_init_poisoning = true;
254 213
255 /* 214 /*
256 * Calling vm_debug with no arguments 215 * Calling vm_debug with no arguments is equivalent to requesting
257 * to enable all debugging options we 216 * to enable all debugging options we can control.
258 */ 217 */
259 if (*str++ != '=' || !*str) 218 if (*str++ != '=' || !*str)
260 goto out; 219 goto out;
261 220
262 __page_init_poisoning = false; 221 __page_init_poisoning = false;
263 if (*str == '-') 222 if (*str == '-')
264 goto out; 223 goto out;
265 224
266 while (*str) { 225 while (*str) {
267 switch (tolower(*str)) { 226 switch (tolower(*str)) {
268 case'p': 227 case'p':
269 __page_init_poisoning 228 __page_init_poisoning = true;
270 break; 229 break;
271 default: 230 default:
272 pr_err("vm_debug optio 231 pr_err("vm_debug option '%c' unknown. skipped\n",
273 *str); 232 *str);
274 } 233 }
275 234
276 str++; 235 str++;
277 } 236 }
278 out: 237 out:
279 if (page_init_poisoning && !__page_ini 238 if (page_init_poisoning && !__page_init_poisoning)
280 pr_warn("Page struct poisoning 239 pr_warn("Page struct poisoning disabled by kernel command line option 'vm_debug'\n");
281 240
282 page_init_poisoning = __page_init_pois 241 page_init_poisoning = __page_init_poisoning;
283 242
284 return 1; 243 return 1;
285 } 244 }
286 __setup("vm_debug", setup_vm_debug); 245 __setup("vm_debug", setup_vm_debug);
287 246
288 void page_init_poison(struct page *page, size_ 247 void page_init_poison(struct page *page, size_t size)
289 { 248 {
290 if (page_init_poisoning) 249 if (page_init_poisoning)
291 memset(page, PAGE_POISON_PATTE 250 memset(page, PAGE_POISON_PATTERN, size);
292 } 251 }
293 !! 252 EXPORT_SYMBOL_GPL(page_init_poison);
294 void vma_iter_dump_tree(const struct vma_itera <<
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 */ 253 #endif /* CONFIG_DEBUG_VM */
303 254
Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.