[linux-block.git] / mm / debug.c

// SPDX-License-Identifier: GPL-2.0
/*
 * mm/debug.c
 *
 * mm/ specific debug routines.
 *
 */

#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/trace_events.h>
#include <linux/memcontrol.h>
#include <trace/events/mmflags.h>
#include <linux/migrate.h>
#include <linux/page_owner.h>
#include <linux/ctype.h>

#include "internal.h"
#include <trace/events/migrate.h>

/*
 * Define EM() and EMe() so that MIGRATE_REASON from trace/events/migrate.h can
 * be used to populate migrate_reason_names[].
 */
#undef EM
#undef EMe
#define EM(a, b)	b,
#define EMe(a, b)	b

const char *migrate_reason_names[MR_TYPES] = {
	MIGRATE_REASON
};

const struct trace_print_flags pageflag_names[] = {
	__def_pageflag_names,
	{0, NULL}
};

const struct trace_print_flags gfpflag_names[] = {
	__def_gfpflag_names,
	{0, NULL}
};

const struct trace_print_flags vmaflag_names[] = {
	__def_vmaflag_names,
	{0, NULL}
};

#define DEF_PAGETYPE_NAME(_name) [PGTY_##_name - 0xf0] =  __stringify(_name)

static const char *page_type_names[] = {
	DEF_PAGETYPE_NAME(slab),
	DEF_PAGETYPE_NAME(hugetlb),
	DEF_PAGETYPE_NAME(offline),
	DEF_PAGETYPE_NAME(guard),
	DEF_PAGETYPE_NAME(table),
	DEF_PAGETYPE_NAME(buddy),
	DEF_PAGETYPE_NAME(unaccepted),
};

static const char *page_type_name(unsigned int page_type)
{
	unsigned i = (page_type >> 24) - 0xf0;

	if (i >= ARRAY_SIZE(page_type_names))
		return "unknown";
	return page_type_names[i];
}

static void __dump_folio(struct folio *folio, struct page *page,
		unsigned long pfn, unsigned long idx)
{
	struct address_space *mapping = folio_mapping(folio);
	int mapcount = atomic_read(&page->_mapcount) + 1;
	char *type = "";

	if (page_mapcount_is_type(mapcount))
		mapcount = 0;

	pr_warn("page: refcount:%d mapcount:%d mapping:%p index:%#lx pfn:%#lx\n",
			folio_ref_count(folio), mapcount, mapping,
			folio->index + idx, pfn);
	if (folio_test_large(folio)) {
		int pincount = 0;

		if (folio_has_pincount(folio))
			pincount = atomic_read(&folio->_pincount);

		pr_warn("head: order:%u mapcount:%d entire_mapcount:%d nr_pages_mapped:%d pincount:%d\n",
				folio_order(folio),
				folio_mapcount(folio),
				folio_entire_mapcount(folio),
				folio_nr_pages_mapped(folio),
				pincount);
	}

#ifdef CONFIG_MEMCG
	if (folio->memcg_data)
		pr_warn("memcg:%lx\n", folio->memcg_data);
#endif
	if (folio_test_ksm(folio))
		type = "ksm ";
	else if (folio_test_anon(folio))
		type = "anon ";
	else if (mapping)
		dump_mapping(mapping);
	BUILD_BUG_ON(ARRAY_SIZE(pageflag_names) != __NR_PAGEFLAGS + 1);

	/*
	 * Accessing the pageblock without the zone lock. It could change to
	 * "isolate" again in the meantime, but since we are just dumping the
	 * state for debugging, it should be fine to accept a bit of
	 * inaccuracy here due to racing.
	 */
	pr_warn("%sflags: %pGp%s\n", type, &folio->flags,
		is_migrate_cma_folio(folio, pfn) ? " CMA" : "");
	if (page_has_type(&folio->page))
		pr_warn("page_type: %x(%s)\n", folio->page.page_type >> 24,
				page_type_name(folio->page.page_type));

	print_hex_dump(KERN_WARNING, "raw: ", DUMP_PREFIX_NONE, 32,
			sizeof(unsigned long), page,
			sizeof(struct page), false);
	if (folio_test_large(folio))
		print_hex_dump(KERN_WARNING, "head: ", DUMP_PREFIX_NONE, 32,
			sizeof(unsigned long), folio,
			2 * sizeof(struct page), false);
}

static void __dump_page(const struct page *page)
{
	struct folio *foliop, folio;
	struct page precise;
	unsigned long head;
	unsigned long pfn = page_to_pfn(page);
	unsigned long idx, nr_pages = 1;
	int loops = 5;

again:
	memcpy(&precise, page, sizeof(*page));
	head = precise.compound_head;
	if ((head & 1) == 0) {
		foliop = (struct folio *)&precise;
		idx = 0;
		if (!folio_test_large(foliop))
			goto dump;
		foliop = (struct folio *)page;
	} else {
		foliop = (struct folio *)(head - 1);
		idx = folio_page_idx(foliop, page);
	}

	if (idx < MAX_FOLIO_NR_PAGES) {
		memcpy(&folio, foliop, 2 * sizeof(struct page));
		nr_pages = folio_nr_pages(&folio);
		if (nr_pages > 1)
			memcpy(&folio.__page_2, &foliop->__page_2,
			       sizeof(struct page));
		foliop = &folio;
	}

	if (idx > nr_pages) {
		if (loops-- > 0)
			goto again;
		pr_warn("page does not match folio\n");
		precise.compound_head &= ~1UL;
		foliop = (struct folio *)&precise;
		idx = 0;
	}

dump:
	__dump_folio(foliop, &precise, pfn, idx);
}

void dump_page(const struct page *page, const char *reason)
{
	if (PagePoisoned(page))
		pr_warn("page:%p is uninitialized and poisoned\n", page);
	else
		__dump_page(page);
	if (reason)
		pr_warn("page dumped because: %s\n", reason);
	dump_page_owner(page);
}
EXPORT_SYMBOL(dump_page);

#ifdef CONFIG_DEBUG_VM

void dump_vma(const struct vm_area_struct *vma)
{
	pr_emerg("vma %px start %px end %px mm %px\n"
		"prot %lx anon_vma %px vm_ops %px\n"
		"pgoff %lx file %px private_data %px\n"
#ifdef CONFIG_PER_VMA_LOCK
		"refcnt %x\n"
#endif
		"flags: %#lx(%pGv)\n",
		vma, (void *)vma->vm_start, (void *)vma->vm_end, vma->vm_mm,
		(unsigned long)pgprot_val(vma->vm_page_prot),
		vma->anon_vma, vma->vm_ops, vma->vm_pgoff,
		vma->vm_file, vma->vm_private_data,
#ifdef CONFIG_PER_VMA_LOCK
		refcount_read(&vma->vm_refcnt),
#endif
		vma->vm_flags, &vma->vm_flags);
}
EXPORT_SYMBOL(dump_vma);

void dump_mm(const struct mm_struct *mm)
{
	pr_emerg("mm %px task_size %lu\n"
		"mmap_base %lu mmap_legacy_base %lu\n"
		"pgd %px mm_users %d mm_count %d pgtables_bytes %lu map_count %d\n"
		"hiwater_rss %lx hiwater_vm %lx total_vm %lx locked_vm %lx\n"
		"pinned_vm %llx data_vm %lx exec_vm %lx stack_vm %lx\n"
		"start_code %lx end_code %lx start_data %lx end_data %lx\n"
		"start_brk %lx brk %lx start_stack %lx\n"
		"arg_start %lx arg_end %lx env_start %lx env_end %lx\n"
		"binfmt %px flags %lx\n"
#ifdef CONFIG_AIO
		"ioctx_table %px\n"
#endif
#ifdef CONFIG_MEMCG
		"owner %px "
#endif
		"exe_file %px\n"
#ifdef CONFIG_MMU_NOTIFIER
		"notifier_subscriptions %px\n"
#endif
#ifdef CONFIG_NUMA_BALANCING
		"numa_next_scan %lu numa_scan_offset %lu numa_scan_seq %d\n"
#endif
		"tlb_flush_pending %d\n"
		"def_flags: %#lx(%pGv)\n",

		mm, mm->task_size,
		mm->mmap_base, mm->mmap_legacy_base,
		mm->pgd, atomic_read(&mm->mm_users),
		atomic_read(&mm->mm_count),
		mm_pgtables_bytes(mm),
		mm->map_count,
		mm->hiwater_rss, mm->hiwater_vm, mm->total_vm, mm->locked_vm,
		(u64)atomic64_read(&mm->pinned_vm),
		mm->data_vm, mm->exec_vm, mm->stack_vm,
		mm->start_code, mm->end_code, mm->start_data, mm->end_data,
		mm->start_brk, mm->brk, mm->start_stack,
		mm->arg_start, mm->arg_end, mm->env_start, mm->env_end,
		mm->binfmt, mm->flags,
#ifdef CONFIG_AIO
		mm->ioctx_table,
#endif
#ifdef CONFIG_MEMCG
		mm->owner,
#endif
		mm->exe_file,
#ifdef CONFIG_MMU_NOTIFIER
		mm->notifier_subscriptions,
#endif
#ifdef CONFIG_NUMA_BALANCING
		mm->numa_next_scan, mm->numa_scan_offset, mm->numa_scan_seq,
#endif
		atomic_read(&mm->tlb_flush_pending),
		mm->def_flags, &mm->def_flags
	);
}
EXPORT_SYMBOL(dump_mm);

void dump_vmg(const struct vma_merge_struct *vmg, const char *reason)
{
	if (reason)
		pr_warn("vmg %px dumped because: %s\n", vmg, reason);

	if (!vmg) {
		pr_warn("vmg %px state: (NULL)\n", vmg);
		return;
	}

	pr_warn("vmg %px state: mm %px pgoff %lx\n"
		"vmi %px [%lx,%lx)\n"
		"prev %px middle %px next %px target %px\n"
		"start %lx end %lx flags %lx\n"
		"file %px anon_vma %px policy %px\n"
		"uffd_ctx %px\n"
		"anon_name %px\n"
		"state %x\n"
		"just_expand %d\n"
		"__adjust_middle_start %d __adjust_next_start %d\n"
		"__remove_middle %d __remove_next %d\n",
		vmg, vmg->mm, vmg->pgoff,
		vmg->vmi, vmg->vmi ? vma_iter_addr(vmg->vmi) : 0,
		vmg->vmi ? vma_iter_end(vmg->vmi) : 0,
		vmg->prev, vmg->middle, vmg->next, vmg->target,
		vmg->start, vmg->end, vmg->flags,
		vmg->file, vmg->anon_vma, vmg->policy,
#ifdef CONFIG_USERFAULTFD
		vmg->uffd_ctx.ctx,
#else
		(void *)0,
#endif
		vmg->anon_name,
		(int)vmg->state,
		vmg->just_expand,
		vmg->__adjust_middle_start, vmg->__adjust_next_start,
		vmg->__remove_middle, vmg->__remove_next);

	if (vmg->mm) {
		pr_warn("vmg %px mm:\n", vmg);
		dump_mm(vmg->mm);
	} else {
		pr_warn("vmg %px mm: (NULL)\n", vmg);
	}

	if (vmg->prev) {
		pr_warn("vmg %px prev:\n", vmg);
		dump_vma(vmg->prev);
	} else {
		pr_warn("vmg %px prev: (NULL)\n", vmg);
	}

	if (vmg->middle) {
		pr_warn("vmg %px middle:\n", vmg);
		dump_vma(vmg->middle);
	} else {
		pr_warn("vmg %px middle: (NULL)\n", vmg);
	}

	if (vmg->next) {
		pr_warn("vmg %px next:\n", vmg);
		dump_vma(vmg->next);
	} else {
		pr_warn("vmg %px next: (NULL)\n", vmg);
	}

#ifdef CONFIG_DEBUG_VM_MAPLE_TREE
	if (vmg->vmi) {
		pr_warn("vmg %px vmi:\n", vmg);
		vma_iter_dump_tree(vmg->vmi);
	} else {
		pr_warn("vmg %px vmi: (NULL)\n", vmg);
	}
#endif
}
EXPORT_SYMBOL(dump_vmg);

static bool page_init_poisoning __read_mostly = true;

static int __init setup_vm_debug(char *str)
{
	bool __page_init_poisoning = true;

	/*
	 * Calling vm_debug with no arguments is equivalent to requesting
	 * to enable all debugging options we can control.
	 */
	if (*str++ != '=' || !*str)
		goto out;

	__page_init_poisoning = false;
	if (*str == '-')
		goto out;

	while (*str) {
		switch (tolower(*str)) {
		case'p':
			__page_init_poisoning = true;
			break;
		default:
			pr_err("vm_debug option '%c' unknown. skipped\n",
			       *str);
		}

		str++;
	}
out:
	if (page_init_poisoning && !__page_init_poisoning)
		pr_warn("Page struct poisoning disabled by kernel command line option 'vm_debug'\n");

	page_init_poisoning = __page_init_poisoning;

	return 1;
}
__setup("vm_debug", setup_vm_debug);

void page_init_poison(struct page *page, size_t size)
{
	if (page_init_poisoning)
		memset(page, PAGE_POISON_PATTERN, size);
}

void vma_iter_dump_tree(const struct vma_iterator *vmi)
{
#if defined(CONFIG_DEBUG_VM_MAPLE_TREE)
	mas_dump(&vmi->mas);
	mt_dump(vmi->mas.tree, mt_dump_hex);
#endif	/* CONFIG_DEBUG_VM_MAPLE_TREE */
}

#endif		/* CONFIG_DEBUG_VM */
Commit	Line	Data
	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	#include <trace/events/migrate.h>
	20
	21	/*
	22	* Define EM() and EMe() so that MIGRATE_REASON from trace/events/migrate.h can
	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
	30	const char *migrate_reason_names[MR_TYPES] = {
	31	MIGRATE_REASON
	32	};
	33
	34	const struct trace_print_flags pageflag_names[] = {
	35	__def_pageflag_names,
	36	{0, NULL}
	37	};
	38
	39	const struct trace_print_flags gfpflag_names[] = {
	40	__def_gfpflag_names,
	41	{0, NULL}
	42	};
	43
	44	const 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
	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 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
	70	static 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) + 1;
	75	char *type = "";
	76
	77	if (page_mapcount_is_type(mapcount))
	78	mapcount = 0;
	79
	80	pr_warn("page: refcount:%d mapcount:%d mapping:%p index:%#lx pfn:%#lx\n",
	81	folio_ref_count(folio), mapcount, mapping,
	82	folio->index + idx, pfn);
	83	if (folio_test_large(folio)) {
	84	int pincount = 0;
	85
	86	if (folio_has_pincount(folio))
	87	pincount = atomic_read(&folio->_pincount);
	88
	89	pr_warn("head: order:%u mapcount:%d entire_mapcount:%d nr_pages_mapped:%d pincount:%d\n",
	90	folio_order(folio),
	91	folio_mapcount(folio),
	92	folio_entire_mapcount(folio),
	93	folio_nr_pages_mapped(folio),
	94	pincount);
	95	}
	96
	97	#ifdef CONFIG_MEMCG
	98	if (folio->memcg_data)
	99	pr_warn("memcg:%lx\n", folio->memcg_data);
	100	#endif
	101	if (folio_test_ksm(folio))
	102	type = "ksm ";
	103	else if (folio_test_anon(folio))
	104	type = "anon ";
	105	else if (mapping)
	106	dump_mapping(mapping);
	107	BUILD_BUG_ON(ARRAY_SIZE(pageflag_names) != __NR_PAGEFLAGS + 1);
	108
	109	/*
	110	* Accessing the pageblock without the zone lock. It could change to
	111	* "isolate" again in the meantime, but since we are just dumping the
	112	* state for debugging, it should be fine to accept a bit of
	113	* inaccuracy here due to racing.
	114	*/
	115	pr_warn("%sflags: %pGp%s\n", type, &folio->flags,
	116	is_migrate_cma_folio(folio, pfn) ? " CMA" : "");
	117	if (page_has_type(&folio->page))
	118	pr_warn("page_type: %x(%s)\n", folio->page.page_type >> 24,
	119	page_type_name(folio->page.page_type));
	120
	121	print_hex_dump(KERN_WARNING, "raw: ", DUMP_PREFIX_NONE, 32,
	122	sizeof(unsigned long), page,
	123	sizeof(struct page), false);
	124	if (folio_test_large(folio))
	125	print_hex_dump(KERN_WARNING, "head: ", DUMP_PREFIX_NONE, 32,
	126	sizeof(unsigned long), folio,
	127	2 * sizeof(struct page), false);
	128	}
	129
	130	static void __dump_page(const struct page *page)
	131	{
	132	struct folio *foliop, folio;
	133	struct page precise;
	134	unsigned long head;
	135	unsigned long pfn = page_to_pfn(page);
	136	unsigned long idx, nr_pages = 1;
	137	int loops = 5;
	138
	139	again:
	140	memcpy(&precise, page, sizeof(*page));
	141	head = precise.compound_head;
	142	if ((head & 1) == 0) {
	143	foliop = (struct folio *)&precise;
	144	idx = 0;
	145	if (!folio_test_large(foliop))
	146	goto dump;
	147	foliop = (struct folio *)page;
	148	} else {
	149	foliop = (struct folio *)(head - 1);
	150	idx = folio_page_idx(foliop, page);
	151	}
	152
	153	if (idx < MAX_FOLIO_NR_PAGES) {
	154	memcpy(&folio, foliop, 2 * sizeof(struct page));
	155	nr_pages = folio_nr_pages(&folio);
	156	if (nr_pages > 1)
	157	memcpy(&folio.__page_2, &foliop->__page_2,
	158	sizeof(struct page));
	159	foliop = &folio;
	160	}
	161
	162	if (idx > nr_pages) {
	163	if (loops-- > 0)
	164	goto again;
	165	pr_warn("page does not match folio\n");
	166	precise.compound_head &= ~1UL;
	167	foliop = (struct folio *)&precise;
	168	idx = 0;
	169	}
	170
	171	dump:
	172	__dump_folio(foliop, &precise, pfn, idx);
	173	}
	174
	175	void dump_page(const struct page page, const char reason)
	176	{
	177	if (PagePoisoned(page))
	178	pr_warn("page:%p is uninitialized and poisoned\n", page);
	179	else
	180	__dump_page(page);
	181	if (reason)
	182	pr_warn("page dumped because: %s\n", reason);
	183	dump_page_owner(page);
	184	}
	185	EXPORT_SYMBOL(dump_page);
	186
	187	#ifdef CONFIG_DEBUG_VM
	188
	189	void dump_vma(const struct vm_area_struct *vma)
	190	{
	191	pr_emerg("vma %px start %px end %px mm %px\n"
	192	"prot %lx anon_vma %px vm_ops %px\n"
	193	"pgoff %lx file %px private_data %px\n"
	194	#ifdef CONFIG_PER_VMA_LOCK
	195	"refcnt %x\n"
	196	#endif
	197	"flags: %#lx(%pGv)\n",
	198	vma, (void )vma->vm_start, (void )vma->vm_end, vma->vm_mm,
	199	(unsigned long)pgprot_val(vma->vm_page_prot),
	200	vma->anon_vma, vma->vm_ops, vma->vm_pgoff,
	201	vma->vm_file, vma->vm_private_data,
	202	#ifdef CONFIG_PER_VMA_LOCK
	203	refcount_read(&vma->vm_refcnt),
	204	#endif
	205	vma->vm_flags, &vma->vm_flags);
	206	}
	207	EXPORT_SYMBOL(dump_vma);
	208
	209	void dump_mm(const struct mm_struct *mm)
	210	{
	211	pr_emerg("mm %px task_size %lu\n"
	212	"mmap_base %lu mmap_legacy_base %lu\n"
	213	"pgd %px mm_users %d mm_count %d pgtables_bytes %lu map_count %d\n"
	214	"hiwater_rss %lx hiwater_vm %lx total_vm %lx locked_vm %lx\n"
	215	"pinned_vm %llx data_vm %lx exec_vm %lx stack_vm %lx\n"
	216	"start_code %lx end_code %lx start_data %lx end_data %lx\n"
	217	"start_brk %lx brk %lx start_stack %lx\n"
	218	"arg_start %lx arg_end %lx env_start %lx env_end %lx\n"
	219	"binfmt %px flags %lx\n"
	220	#ifdef CONFIG_AIO
	221	"ioctx_table %px\n"
	222	#endif
	223	#ifdef CONFIG_MEMCG
	224	"owner %px "
	225	#endif
	226	"exe_file %px\n"
	227	#ifdef CONFIG_MMU_NOTIFIER
	228	"notifier_subscriptions %px\n"
	229	#endif
	230	#ifdef CONFIG_NUMA_BALANCING
	231	"numa_next_scan %lu numa_scan_offset %lu numa_scan_seq %d\n"
	232	#endif
	233	"tlb_flush_pending %d\n"
	234	"def_flags: %#lx(%pGv)\n",
	235
	236	mm, mm->task_size,
	237	mm->mmap_base, mm->mmap_legacy_base,
	238	mm->pgd, atomic_read(&mm->mm_users),
	239	atomic_read(&mm->mm_count),
	240	mm_pgtables_bytes(mm),
	241	mm->map_count,
	242	mm->hiwater_rss, mm->hiwater_vm, mm->total_vm, mm->locked_vm,
	243	(u64)atomic64_read(&mm->pinned_vm),
	244	mm->data_vm, mm->exec_vm, mm->stack_vm,
	245	mm->start_code, mm->end_code, mm->start_data, mm->end_data,
	246	mm->start_brk, mm->brk, mm->start_stack,
	247	mm->arg_start, mm->arg_end, mm->env_start, mm->env_end,
	248	mm->binfmt, mm->flags,
	249	#ifdef CONFIG_AIO
	250	mm->ioctx_table,
	251	#endif
	252	#ifdef CONFIG_MEMCG
	253	mm->owner,
	254	#endif
	255	mm->exe_file,
	256	#ifdef CONFIG_MMU_NOTIFIER
	257	mm->notifier_subscriptions,
	258	#endif
	259	#ifdef CONFIG_NUMA_BALANCING
	260	mm->numa_next_scan, mm->numa_scan_offset, mm->numa_scan_seq,
	261	#endif
	262	atomic_read(&mm->tlb_flush_pending),
	263	mm->def_flags, &mm->def_flags
	264	);
	265	}
	266	EXPORT_SYMBOL(dump_mm);
	267
	268	void dump_vmg(const struct vma_merge_struct vmg, const char reason)
	269	{
	270	if (reason)
	271	pr_warn("vmg %px dumped because: %s\n", vmg, reason);
	272
	273	if (!vmg) {
	274	pr_warn("vmg %px state: (NULL)\n", vmg);
	275	return;
	276	}
	277
	278	pr_warn("vmg %px state: mm %px pgoff %lx\n"
	279	"vmi %px [%lx,%lx)\n"
	280	"prev %px middle %px next %px target %px\n"
	281	"start %lx end %lx flags %lx\n"
	282	"file %px anon_vma %px policy %px\n"
	283	"uffd_ctx %px\n"
	284	"anon_name %px\n"
	285	"state %x\n"
	286	"just_expand %d\n"
	287	"__adjust_middle_start %d __adjust_next_start %d\n"
	288	"__remove_middle %d __remove_next %d\n",
	289	vmg, vmg->mm, vmg->pgoff,
	290	vmg->vmi, vmg->vmi ? vma_iter_addr(vmg->vmi) : 0,
	291	vmg->vmi ? vma_iter_end(vmg->vmi) : 0,
	292	vmg->prev, vmg->middle, vmg->next, vmg->target,
	293	vmg->start, vmg->end, vmg->flags,
	294	vmg->file, vmg->anon_vma, vmg->policy,
	295	#ifdef CONFIG_USERFAULTFD
	296	vmg->uffd_ctx.ctx,
	297	#else
	298	(void *)0,
	299	#endif
	300	vmg->anon_name,
	301	(int)vmg->state,
	302	vmg->just_expand,
	303	vmg->__adjust_middle_start, vmg->__adjust_next_start,
	304	vmg->__remove_middle, vmg->__remove_next);
	305
	306	if (vmg->mm) {
	307	pr_warn("vmg %px mm:\n", vmg);
	308	dump_mm(vmg->mm);
	309	} else {
	310	pr_warn("vmg %px mm: (NULL)\n", vmg);
	311	}
	312
	313	if (vmg->prev) {
	314	pr_warn("vmg %px prev:\n", vmg);
	315	dump_vma(vmg->prev);
	316	} else {
	317	pr_warn("vmg %px prev: (NULL)\n", vmg);
	318	}
	319
	320	if (vmg->middle) {
	321	pr_warn("vmg %px middle:\n", vmg);
	322	dump_vma(vmg->middle);
	323	} else {
	324	pr_warn("vmg %px middle: (NULL)\n", vmg);
	325	}
	326
	327	if (vmg->next) {
	328	pr_warn("vmg %px next:\n", vmg);
	329	dump_vma(vmg->next);
	330	} else {
	331	pr_warn("vmg %px next: (NULL)\n", vmg);
	332	}
	333
	334	#ifdef CONFIG_DEBUG_VM_MAPLE_TREE
	335	if (vmg->vmi) {
	336	pr_warn("vmg %px vmi:\n", vmg);
	337	vma_iter_dump_tree(vmg->vmi);
	338	} else {
	339	pr_warn("vmg %px vmi: (NULL)\n", vmg);
	340	}
	341	#endif
	342	}
	343	EXPORT_SYMBOL(dump_vmg);
	344
	345	static bool page_init_poisoning __read_mostly = true;
	346
	347	static int __init setup_vm_debug(char *str)
	348	{
	349	bool __page_init_poisoning = true;
	350
	351	/*
	352	* Calling vm_debug with no arguments is equivalent to requesting
	353	* to enable all debugging options we can control.
	354	*/
	355	if (str++ != '=' \|\| !str)
	356	goto out;
	357
	358	__page_init_poisoning = false;
	359	if (*str == '-')
	360	goto out;
	361
	362	while (*str) {
	363	switch (tolower(*str)) {
	364	case'p':
	365	__page_init_poisoning = true;
	366	break;
	367	default:
	368	pr_err("vm_debug option '%c' unknown. skipped\n",
	369	*str);
	370	}
	371
	372	str++;
	373	}
	374	out:
	375	if (page_init_poisoning && !__page_init_poisoning)
	376	pr_warn("Page struct poisoning disabled by kernel command line option 'vm_debug'\n");
	377
	378	page_init_poisoning = __page_init_poisoning;
	379
	380	return 1;
	381	}
	382	__setup("vm_debug", setup_vm_debug);
	383
	384	void page_init_poison(struct page *page, size_t size)
	385	{
	386	if (page_init_poisoning)
	387	memset(page, PAGE_POISON_PATTERN, size);
	388	}
	389
	390	void vma_iter_dump_tree(const struct vma_iterator *vmi)
	391	{
	392	#if defined(CONFIG_DEBUG_VM_MAPLE_TREE)
	393	mas_dump(&vmi->mas);
	394	mt_dump(vmi->mas.tree, mt_dump_hex);
	395	#endif /* CONFIG_DEBUG_VM_MAPLE_TREE */
	396	}
	397
	398	#endif /* CONFIG_DEBUG_VM */