// 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 */