Merge tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
[muen/linux.git] / mm / debug.c
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * mm/debug.c
4  *
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
20 const char *migrate_reason_names[MR_TYPES] = {
21         "compaction",
22         "memory_failure",
23         "memory_hotplug",
24         "syscall_or_cpuset",
25         "mempolicy_mbind",
26         "numa_misplaced",
27         "cma",
28 };
29
30 const struct trace_print_flags pageflag_names[] = {
31         __def_pageflag_names,
32         {0, NULL}
33 };
34
35 const struct trace_print_flags gfpflag_names[] = {
36         __def_gfpflag_names,
37         {0, NULL}
38 };
39
40 const struct trace_print_flags vmaflag_names[] = {
41         __def_vmaflag_names,
42         {0, NULL}
43 };
44
45 void __dump_page(struct page *page, const char *reason)
46 {
47         struct address_space *mapping;
48         bool page_poisoned = PagePoisoned(page);
49         int mapcount;
50
51         /*
52          * If struct page is poisoned don't access Page*() functions as that
53          * leads to recursive loop. Page*() check for poisoned pages, and calls
54          * dump_page() when detected.
55          */
56         if (page_poisoned) {
57                 pr_warn("page:%px is uninitialized and poisoned", page);
58                 goto hex_only;
59         }
60
61         mapping = page_mapping(page);
62
63         /*
64          * Avoid VM_BUG_ON() in page_mapcount().
65          * page->_mapcount space in struct page is used by sl[aou]b pages to
66          * encode own info.
67          */
68         mapcount = PageSlab(page) ? 0 : page_mapcount(page);
69
70         pr_warn("page:%px count:%d mapcount:%d mapping:%px index:%#lx",
71                   page, page_ref_count(page), mapcount,
72                   page->mapping, page_to_pgoff(page));
73         if (PageCompound(page))
74                 pr_cont(" compound_mapcount: %d", compound_mapcount(page));
75         pr_cont("\n");
76         if (PageAnon(page))
77                 pr_warn("anon ");
78         else if (PageKsm(page))
79                 pr_warn("ksm ");
80         else if (mapping) {
81                 pr_warn("%ps ", mapping->a_ops);
82                 if (mapping->host->i_dentry.first) {
83                         struct dentry *dentry;
84                         dentry = container_of(mapping->host->i_dentry.first, struct dentry, d_u.d_alias);
85                         pr_warn("name:\"%pd\" ", dentry);
86                 }
87         }
88         BUILD_BUG_ON(ARRAY_SIZE(pageflag_names) != __NR_PAGEFLAGS + 1);
89
90         pr_warn("flags: %#lx(%pGp)\n", page->flags, &page->flags);
91
92 hex_only:
93         print_hex_dump(KERN_WARNING, "raw: ", DUMP_PREFIX_NONE, 32,
94                         sizeof(unsigned long), page,
95                         sizeof(struct page), false);
96
97         if (reason)
98                 pr_warn("page dumped because: %s\n", reason);
99
100 #ifdef CONFIG_MEMCG
101         if (!page_poisoned && page->mem_cgroup)
102                 pr_warn("page->mem_cgroup:%px\n", page->mem_cgroup);
103 #endif
104 }
105
106 void dump_page(struct page *page, const char *reason)
107 {
108         __dump_page(page, reason);
109         dump_page_owner(page);
110 }
111 EXPORT_SYMBOL(dump_page);
112
113 #ifdef CONFIG_DEBUG_VM
114
115 void dump_vma(const struct vm_area_struct *vma)
116 {
117         pr_emerg("vma %px start %px end %px\n"
118                 "next %px prev %px mm %px\n"
119                 "prot %lx anon_vma %px vm_ops %px\n"
120                 "pgoff %lx file %px private_data %px\n"
121                 "flags: %#lx(%pGv)\n",
122                 vma, (void *)vma->vm_start, (void *)vma->vm_end, vma->vm_next,
123                 vma->vm_prev, vma->vm_mm,
124                 (unsigned long)pgprot_val(vma->vm_page_prot),
125                 vma->anon_vma, vma->vm_ops, vma->vm_pgoff,
126                 vma->vm_file, vma->vm_private_data,
127                 vma->vm_flags, &vma->vm_flags);
128 }
129 EXPORT_SYMBOL(dump_vma);
130
131 void dump_mm(const struct mm_struct *mm)
132 {
133         pr_emerg("mm %px mmap %px seqnum %llu task_size %lu\n"
134 #ifdef CONFIG_MMU
135                 "get_unmapped_area %px\n"
136 #endif
137                 "mmap_base %lu mmap_legacy_base %lu highest_vm_end %lu\n"
138                 "pgd %px mm_users %d mm_count %d pgtables_bytes %lu map_count %d\n"
139                 "hiwater_rss %lx hiwater_vm %lx total_vm %lx locked_vm %lx\n"
140                 "pinned_vm %llx data_vm %lx exec_vm %lx stack_vm %lx\n"
141                 "start_code %lx end_code %lx start_data %lx end_data %lx\n"
142                 "start_brk %lx brk %lx start_stack %lx\n"
143                 "arg_start %lx arg_end %lx env_start %lx env_end %lx\n"
144                 "binfmt %px flags %lx core_state %px\n"
145 #ifdef CONFIG_AIO
146                 "ioctx_table %px\n"
147 #endif
148 #ifdef CONFIG_MEMCG
149                 "owner %px "
150 #endif
151                 "exe_file %px\n"
152 #ifdef CONFIG_MMU_NOTIFIER
153                 "mmu_notifier_mm %px\n"
154 #endif
155 #ifdef CONFIG_NUMA_BALANCING
156                 "numa_next_scan %lu numa_scan_offset %lu numa_scan_seq %d\n"
157 #endif
158                 "tlb_flush_pending %d\n"
159                 "def_flags: %#lx(%pGv)\n",
160
161                 mm, mm->mmap, (long long) mm->vmacache_seqnum, mm->task_size,
162 #ifdef CONFIG_MMU
163                 mm->get_unmapped_area,
164 #endif
165                 mm->mmap_base, mm->mmap_legacy_base, mm->highest_vm_end,
166                 mm->pgd, atomic_read(&mm->mm_users),
167                 atomic_read(&mm->mm_count),
168                 mm_pgtables_bytes(mm),
169                 mm->map_count,
170                 mm->hiwater_rss, mm->hiwater_vm, mm->total_vm, mm->locked_vm,
171                 atomic64_read(&mm->pinned_vm),
172                 mm->data_vm, mm->exec_vm, mm->stack_vm,
173                 mm->start_code, mm->end_code, mm->start_data, mm->end_data,
174                 mm->start_brk, mm->brk, mm->start_stack,
175                 mm->arg_start, mm->arg_end, mm->env_start, mm->env_end,
176                 mm->binfmt, mm->flags, mm->core_state,
177 #ifdef CONFIG_AIO
178                 mm->ioctx_table,
179 #endif
180 #ifdef CONFIG_MEMCG
181                 mm->owner,
182 #endif
183                 mm->exe_file,
184 #ifdef CONFIG_MMU_NOTIFIER
185                 mm->mmu_notifier_mm,
186 #endif
187 #ifdef CONFIG_NUMA_BALANCING
188                 mm->numa_next_scan, mm->numa_scan_offset, mm->numa_scan_seq,
189 #endif
190                 atomic_read(&mm->tlb_flush_pending),
191                 mm->def_flags, &mm->def_flags
192         );
193 }
194
195 static bool page_init_poisoning __read_mostly = true;
196
197 static int __init setup_vm_debug(char *str)
198 {
199         bool __page_init_poisoning = true;
200
201         /*
202          * Calling vm_debug with no arguments is equivalent to requesting
203          * to enable all debugging options we can control.
204          */
205         if (*str++ != '=' || !*str)
206                 goto out;
207
208         __page_init_poisoning = false;
209         if (*str == '-')
210                 goto out;
211
212         while (*str) {
213                 switch (tolower(*str)) {
214                 case'p':
215                         __page_init_poisoning = true;
216                         break;
217                 default:
218                         pr_err("vm_debug option '%c' unknown. skipped\n",
219                                *str);
220                 }
221
222                 str++;
223         }
224 out:
225         if (page_init_poisoning && !__page_init_poisoning)
226                 pr_warn("Page struct poisoning disabled by kernel command line option 'vm_debug'\n");
227
228         page_init_poisoning = __page_init_poisoning;
229
230         return 1;
231 }
232 __setup("vm_debug", setup_vm_debug);
233
234 void page_init_poison(struct page *page, size_t size)
235 {
236         if (page_init_poisoning)
237                 memset(page, PAGE_POISON_PATTERN, size);
238 }
239 EXPORT_SYMBOL_GPL(page_init_poison);
240 #endif          /* CONFIG_DEBUG_VM */