[linux-2.6-block.git] / arch / powerpc / mm / ptdump / ptdump.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright 2016, Rashmica Gupta, IBM Corp.
 *
 * This traverses the kernel pagetables and dumps the
 * information about the used sections of memory to
 * /sys/kernel/debug/kernel_pagetables.
 *
 * Derived from the arm64 implementation:
 * Copyright (c) 2014, The Linux Foundation, Laura Abbott.
 * (C) Copyright 2008 Intel Corporation, Arjan van de Ven.
 */
#include <linux/debugfs.h>
#include <linux/fs.h>
#include <linux/hugetlb.h>
#include <linux/io.h>
#include <linux/mm.h>
#include <linux/highmem.h>
#include <linux/ptdump.h>
#include <linux/sched.h>
#include <linux/seq_file.h>
#include <asm/fixmap.h>
#include <linux/const.h>
#include <linux/kasan.h>
#include <asm/page.h>
#include <asm/hugetlb.h>

#include <mm/mmu_decl.h>

#include "ptdump.h"

/*
 * To visualise what is happening,
 *
 *  - PTRS_PER_P** = how many entries there are in the corresponding P**
 *  - P**_SHIFT = how many bits of the address we use to index into the
 * corresponding P**
 *  - P**_SIZE is how much memory we can access through the table - not the
 * size of the table itself.
 * P**={PGD, PUD, PMD, PTE}
 *
 *
 * Each entry of the PGD points to a PUD. Each entry of a PUD points to a
 * PMD. Each entry of a PMD points to a PTE. And every PTE entry points to
 * a page.
 *
 * In the case where there are only 3 levels, the PUD is folded into the
 * PGD: every PUD has only one entry which points to the PMD.
 *
 * The page dumper groups page table entries of the same type into a single
 * description. It uses pg_state to track the range information while
 * iterating over the PTE entries. When the continuity is broken it then
 * dumps out a description of the range - ie PTEs that are virtually contiguous
 * with the same PTE flags are chunked together. This is to make it clear how
 * different areas of the kernel virtual memory are used.
 *
 */
struct pg_state {
	struct ptdump_state ptdump;
	struct seq_file *seq;
	const struct addr_marker *marker;
	unsigned long start_address;
	unsigned long start_pa;
	int level;
	u64 current_flags;
	bool check_wx;
	unsigned long wx_pages;
};

struct addr_marker {
	unsigned long start_address;
	const char *name;
};

static struct addr_marker address_markers[] = {
	{ 0,	"Start of kernel VM" },
#ifdef MODULES_VADDR
	{ 0,	"modules start" },
	{ 0,	"modules end" },
#endif
	{ 0,	"vmalloc() Area" },
	{ 0,	"vmalloc() End" },
#ifdef CONFIG_PPC64
	{ 0,	"isa I/O start" },
	{ 0,	"isa I/O end" },
	{ 0,	"phb I/O start" },
	{ 0,	"phb I/O end" },
	{ 0,	"I/O remap start" },
	{ 0,	"I/O remap end" },
	{ 0,	"vmemmap start" },
#else
	{ 0,	"Early I/O remap start" },
	{ 0,	"Early I/O remap end" },
#ifdef CONFIG_HIGHMEM
	{ 0,	"Highmem PTEs start" },
	{ 0,	"Highmem PTEs end" },
#endif
	{ 0,	"Fixmap start" },
	{ 0,	"Fixmap end" },
#endif
#ifdef CONFIG_KASAN
	{ 0,	"kasan shadow mem start" },
	{ 0,	"kasan shadow mem end" },
#endif
	{ -1,	NULL },
};

static struct ptdump_range ptdump_range[] __ro_after_init = {
	{TASK_SIZE_MAX, ~0UL},
	{0, 0}
};

#define pt_dump_seq_printf(m, fmt, args...)	\
({						\
	if (m)					\
		seq_printf(m, fmt, ##args);	\
})

#define pt_dump_seq_putc(m, c)		\
({					\
	if (m)				\
		seq_putc(m, c);		\
})

void pt_dump_size(struct seq_file *m, unsigned long size)
{
	static const char units[] = " KMGTPE";
	const char *unit = units;

	/* Work out what appropriate unit to use */
	while (!(size & 1023) && unit[1]) {
		size >>= 10;
		unit++;
	}
	pt_dump_seq_printf(m, "%9lu%c ", size, *unit);
}

static void dump_flag_info(struct pg_state *st, const struct flag_info
		*flag, u64 pte, int num)
{
	unsigned int i;

	for (i = 0; i < num; i++, flag++) {
		const char *s = NULL;
		u64 val;

		/* flag not defined so don't check it */
		if (flag->mask == 0)
			continue;
		/* Some 'flags' are actually values */
		if (flag->is_val) {
			val = pte & flag->val;
			if (flag->shift)
				val = val >> flag->shift;
			pt_dump_seq_printf(st->seq, "  %s:%llx", flag->set, val);
		} else {
			if ((pte & flag->mask) == flag->val)
				s = flag->set;
			else
				s = flag->clear;
			if (s)
				pt_dump_seq_printf(st->seq, "  %s", s);
		}
		st->current_flags &= ~flag->mask;
	}
	if (st->current_flags != 0)
		pt_dump_seq_printf(st->seq, "  unknown flags:%llx", st->current_flags);
}

static void dump_addr(struct pg_state *st, unsigned long addr)
{
#ifdef CONFIG_PPC64
#define REG		"0x%016lx"
#else
#define REG		"0x%08lx"
#endif

	pt_dump_seq_printf(st->seq, REG "-" REG " ", st->start_address, addr - 1);
	pt_dump_seq_printf(st->seq, " " REG " ", st->start_pa);
	pt_dump_size(st->seq, addr - st->start_address);
}

static void note_prot_wx(struct pg_state *st, unsigned long addr)
{
	pte_t pte = __pte(st->current_flags);

	if (!IS_ENABLED(CONFIG_DEBUG_WX) || !st->check_wx)
		return;

	if (!pte_write(pte) || !pte_exec(pte))
		return;

	WARN_ONCE(1, "powerpc/mm: Found insecure W+X mapping at address %p/%pS\n",
		  (void *)st->start_address, (void *)st->start_address);

	st->wx_pages += (addr - st->start_address) / PAGE_SIZE;
}

static void note_page_update_state(struct pg_state *st, unsigned long addr, int level, u64 val)
{
	u64 flag = level >= 0 ? val & pg_level[level].mask : 0;
	u64 pa = val & PTE_RPN_MASK;

	st->level = level;
	st->current_flags = flag;
	st->start_address = addr;
	st->start_pa = pa;

	while (addr >= st->marker[1].start_address) {
		st->marker++;
		pt_dump_seq_printf(st->seq, "---[ %s ]---\n", st->marker->name);
	}
}

static void note_page(struct ptdump_state *pt_st, unsigned long addr, int level, u64 val)
{
	u64 flag = level >= 0 ? val & pg_level[level].mask : 0;
	struct pg_state *st = container_of(pt_st, struct pg_state, ptdump);

	/* At first no level is set */
	if (st->level == -1) {
		pt_dump_seq_printf(st->seq, "---[ %s ]---\n", st->marker->name);
		note_page_update_state(st, addr, level, val);
	/*
	 * Dump the section of virtual memory when:
	 *   - the PTE flags from one entry to the next differs.
	 *   - we change levels in the tree.
	 *   - the address is in a different section of memory and is thus
	 *   used for a different purpose, regardless of the flags.
	 */
	} else if (flag != st->current_flags || level != st->level ||
		   addr >= st->marker[1].start_address) {

		/* Check the PTE flags */
		if (st->current_flags) {
			note_prot_wx(st, addr);
			dump_addr(st, addr);

			/* Dump all the flags */
			if (pg_level[st->level].flag)
				dump_flag_info(st, pg_level[st->level].flag,
					  st->current_flags,
					  pg_level[st->level].num);

			pt_dump_seq_putc(st->seq, '\n');
		}

		/*
		 * Address indicates we have passed the end of the
		 * current section of virtual memory
		 */
		note_page_update_state(st, addr, level, val);
	}
}

static void populate_markers(void)
{
	int i = 0;

#ifdef CONFIG_PPC64
	address_markers[i++].start_address = PAGE_OFFSET;
#else
	address_markers[i++].start_address = TASK_SIZE;
#endif
#ifdef MODULES_VADDR
	address_markers[i++].start_address = MODULES_VADDR;
	address_markers[i++].start_address = MODULES_END;
#endif
	address_markers[i++].start_address = VMALLOC_START;
	address_markers[i++].start_address = VMALLOC_END;
#ifdef CONFIG_PPC64
	address_markers[i++].start_address = ISA_IO_BASE;
	address_markers[i++].start_address = ISA_IO_END;
	address_markers[i++].start_address = PHB_IO_BASE;
	address_markers[i++].start_address = PHB_IO_END;
	address_markers[i++].start_address = IOREMAP_BASE;
	address_markers[i++].start_address = IOREMAP_END;
	/* What is the ifdef about? */
#ifdef CONFIG_PPC_BOOK3S_64
	address_markers[i++].start_address =  H_VMEMMAP_START;
#else
	address_markers[i++].start_address =  VMEMMAP_BASE;
#endif
#else /* !CONFIG_PPC64 */
	address_markers[i++].start_address = ioremap_bot;
	address_markers[i++].start_address = IOREMAP_TOP;
#ifdef CONFIG_HIGHMEM
	address_markers[i++].start_address = PKMAP_BASE;
	address_markers[i++].start_address = PKMAP_ADDR(LAST_PKMAP);
#endif
	address_markers[i++].start_address = FIXADDR_START;
	address_markers[i++].start_address = FIXADDR_TOP;
#endif /* CONFIG_PPC64 */
#ifdef CONFIG_KASAN
	address_markers[i++].start_address = KASAN_SHADOW_START;
	address_markers[i++].start_address = KASAN_SHADOW_END;
#endif
}

static int ptdump_show(struct seq_file *m, void *v)
{
	struct pg_state st = {
		.seq = m,
		.marker = address_markers,
		.level = -1,
		.ptdump = {
			.note_page = note_page,
			.range = ptdump_range,
		}
	};

	/* Traverse kernel page tables */
	ptdump_walk_pgd(&st.ptdump, &init_mm, NULL);
	return 0;
}

DEFINE_SHOW_ATTRIBUTE(ptdump);

static void __init build_pgtable_complete_mask(void)
{
	unsigned int i, j;

	for (i = 0; i < ARRAY_SIZE(pg_level); i++)
		if (pg_level[i].flag)
			for (j = 0; j < pg_level[i].num; j++)
				pg_level[i].mask |= pg_level[i].flag[j].mask;
}

#ifdef CONFIG_DEBUG_WX
void ptdump_check_wx(void)
{
	struct pg_state st = {
		.seq = NULL,
		.marker = (struct addr_marker[]) {
			{ 0, NULL},
			{ -1, NULL},
		},
		.level = -1,
		.check_wx = true,
		.ptdump = {
			.note_page = note_page,
			.range = ptdump_range,
		}
	};

	ptdump_walk_pgd(&st.ptdump, &init_mm, NULL);

	if (st.wx_pages)
		pr_warn("Checked W+X mappings: FAILED, %lu W+X pages found\n",
			st.wx_pages);
	else
		pr_info("Checked W+X mappings: passed, no W+X pages found\n");
}
#endif

static int __init ptdump_init(void)
{
#ifdef CONFIG_PPC64
	if (!radix_enabled())
		ptdump_range[0].start = KERN_VIRT_START;
	else
		ptdump_range[0].start = PAGE_OFFSET;

	ptdump_range[0].end = PAGE_OFFSET + (PGDIR_SIZE * PTRS_PER_PGD);
#endif

	populate_markers();
	build_pgtable_complete_mask();

	if (IS_ENABLED(CONFIG_PTDUMP_DEBUGFS))
		debugfs_create_file("kernel_page_tables", 0400, NULL, NULL, &ptdump_fops);

	return 0;
}
device_initcall(ptdump_init);
Commit	Line	Data
b886d83c	1	// SPDX-License-Identifier: GPL-2.0-only
8eb07b18 RG	2	/*
	3	* Copyright 2016, Rashmica Gupta, IBM Corp.
	4	*
	5	* This traverses the kernel pagetables and dumps the
	6	* information about the used sections of memory to
	7	* /sys/kernel/debug/kernel_pagetables.
	8	*
	9	* Derived from the arm64 implementation:
	10	* Copyright (c) 2014, The Linux Foundation, Laura Abbott.
	11	* (C) Copyright 2008 Intel Corporation, Arjan van de Ven.
8eb07b18 RG	12	*/
	13	#include <linux/debugfs.h>
	14	#include <linux/fs.h>
bfb9956a	15	#include <linux/hugetlb.h>
8eb07b18 RG	16	#include <linux/io.h>
8eb07b18 RG	17	#include <linux/mm.h>
462951cd	18	#include <linux/highmem.h>
e0847283	19	#include <linux/ptdump.h>
8eb07b18 RG	20	#include <linux/sched.h>
	21	#include <linux/seq_file.h>
	22	#include <asm/fixmap.h>
8eb07b18	23	#include <linux/const.h>
41b7a347	24	#include <linux/kasan.h>
8eb07b18	25	#include <asm/page.h>
6b789a26	26	#include <asm/hugetlb.h>
8eb07b18	27
1e1c8b2c CL	28	#include <mm/mmu_decl.h>
1e1c8b2c CL	29
e66c3209	30	#include "ptdump.h"
97026b5a	31
8eb07b18 RG	32	/*
	33	* To visualise what is happening,
	34	*
	35	* - PTRS_PER_P = how many entries there are in the corresponding P
	36	* - P**_SHIFT = how many bits of the address we use to index into the
	37	* corresponding P**
	38	* - P**_SIZE is how much memory we can access through the table - not the
	39	* size of the table itself.
	40	* P**={PGD, PUD, PMD, PTE}
	41	*
	42	*
	43	* Each entry of the PGD points to a PUD. Each entry of a PUD points to a
	44	* PMD. Each entry of a PMD points to a PTE. And every PTE entry points to
	45	* a page.
	46	*
	47	* In the case where there are only 3 levels, the PUD is folded into the
	48	* PGD: every PUD has only one entry which points to the PMD.
	49	*
	50	* The page dumper groups page table entries of the same type into a single
	51	* description. It uses pg_state to track the range information while
	52	* iterating over the PTE entries. When the continuity is broken it then
	53	* dumps out a description of the range - ie PTEs that are virtually contiguous
	54	* with the same PTE flags are chunked together. This is to make it clear how
	55	* different areas of the kernel virtual memory are used.
	56	*
	57	*/
	58	struct pg_state {
e0847283	59	struct ptdump_state ptdump;
8eb07b18 RG	60	struct seq_file *seq;
	61	const struct addr_marker *marker;
	62	unsigned long start_address;
aaa22952	63	unsigned long start_pa;
cf98d2b6	64	int level;
8eb07b18	65	u64 current_flags;
453d87f6 RC	66	bool check_wx;
453d87f6 RC	67	unsigned long wx_pages;
8eb07b18 RG	68	};
	69
	70	struct addr_marker {
	71	unsigned long start_address;
	72	const char *name;
	73	};
	74
	75	static struct addr_marker address_markers[] = {
	76	{ 0, "Start of kernel VM" },
6ca05532 CL	77	#ifdef MODULES_VADDR
	78	{ 0, "modules start" },
	79	{ 0, "modules end" },
	80	#endif
8eb07b18 RG	81	{ 0, "vmalloc() Area" },
8eb07b18 RG	82	{ 0, "vmalloc() End" },
6c01bbd2	83	#ifdef CONFIG_PPC64
8eb07b18 RG	84	{ 0, "isa I/O start" },
	85	{ 0, "isa I/O end" },
	86	{ 0, "phb I/O start" },
	87	{ 0, "phb I/O end" },
	88	{ 0, "I/O remap start" },
	89	{ 0, "I/O remap end" },
	90	{ 0, "vmemmap start" },
6c01bbd2 CL	91	#else
	92	{ 0, "Early I/O remap start" },
	93	{ 0, "Early I/O remap end" },
6c01bbd2 CL	94	#ifdef CONFIG_HIGHMEM
	95	{ 0, "Highmem PTEs start" },
	96	{ 0, "Highmem PTEs end" },
	97	#endif
	98	{ 0, "Fixmap start" },
	99	{ 0, "Fixmap end" },
b4abe38f CL	100	#endif
	101	#ifdef CONFIG_KASAN
	102	{ 0, "kasan shadow mem start" },
	103	{ 0, "kasan shadow mem end" },
6c01bbd2	104	#endif
8eb07b18 RG	105	{ -1, NULL },
	106	};
	107
e0847283 CL	108	static struct ptdump_range ptdump_range[] __ro_after_init = {
	109	{TASK_SIZE_MAX, ~0UL},
	110	{0, 0}
	111	};
	112
5f18cbdb RC	113	#define pt_dump_seq_printf(m, fmt, args...) \
	114	({ \
	115	if (m) \
	116	seq_printf(m, fmt, ##args); \
	117	})
	118
	119	#define pt_dump_seq_putc(m, c) \
	120	({ \
	121	if (m) \
	122	seq_putc(m, c); \
	123	})
	124
6b30830e CL	125	void pt_dump_size(struct seq_file *m, unsigned long size)
6b30830e CL	126	{
cdc81aec	127	static const char units[] = " KMGTPE";
6b30830e CL	128	const char *unit = units;
	129
	130	/* Work out what appropriate unit to use */
	131	while (!(size & 1023) && unit[1]) {
	132	size >>= 10;
	133	unit++;
	134	}
	135	pt_dump_seq_printf(m, "%9lu%c ", size, *unit);
	136	}
	137
8eb07b18 RG	138	static void dump_flag_info(struct pg_state *st, const struct flag_info
	139	*flag, u64 pte, int num)
	140	{
	141	unsigned int i;
	142
	143	for (i = 0; i < num; i++, flag++) {
	144	const char *s = NULL;
	145	u64 val;
	146
	147	/* flag not defined so don't check it */
	148	if (flag->mask == 0)
	149	continue;
	150	/* Some 'flags' are actually values */
	151	if (flag->is_val) {
	152	val = pte & flag->val;
	153	if (flag->shift)
	154	val = val >> flag->shift;
5f18cbdb	155	pt_dump_seq_printf(st->seq, " %s:%llx", flag->set, val);
8eb07b18 RG	156	} else {
	157	if ((pte & flag->mask) == flag->val)
	158	s = flag->set;
	159	else
	160	s = flag->clear;
	161	if (s)
5f18cbdb	162	pt_dump_seq_printf(st->seq, " %s", s);
8eb07b18 RG	163	}
	164	st->current_flags &= ~flag->mask;
	165	}
	166	if (st->current_flags != 0)
5f18cbdb	167	pt_dump_seq_printf(st->seq, " unknown flags:%llx", st->current_flags);
8eb07b18 RG	168	}
	169
	170	static void dump_addr(struct pg_state *st, unsigned long addr)
	171	{
78a18dbf	172	#ifdef CONFIG_PPC64
cabe8138	173	#define REG "0x%016lx"
78a18dbf	174	#else
cabe8138	175	#define REG "0x%08lx"
78a18dbf	176	#endif
aaa22952	177
5f18cbdb	178	pt_dump_seq_printf(st->seq, REG "-" REG " ", st->start_address, addr - 1);
6ca6512c	179	pt_dump_seq_printf(st->seq, " " REG " ", st->start_pa);
cdc81aec	180	pt_dump_size(st->seq, addr - st->start_address);
8eb07b18 RG	181	}
8eb07b18 RG	182
453d87f6 RC	183	static void note_prot_wx(struct pg_state *st, unsigned long addr)
453d87f6 RC	184	{
d80ae83f CL	185	pte_t pte = __pte(st->current_flags);
d80ae83f CL	186
8d84fca4	187	if (!IS_ENABLED(CONFIG_DEBUG_WX) \|\| !st->check_wx)
453d87f6 RC	188	return;
453d87f6 RC	189
d80ae83f	190	if (!pte_write(pte) \|\| !pte_exec(pte))
453d87f6 RC	191	return;
	192
	193	WARN_ONCE(1, "powerpc/mm: Found insecure W+X mapping at address %p/%pS\n",
	194	(void )st->start_address, (void )st->start_address);
	195
	196	st->wx_pages += (addr - st->start_address) / PAGE_SIZE;
	197	}
	198
cf98d2b6	199	static void note_page_update_state(struct pg_state *st, unsigned long addr, int level, u64 val)
e54e30bc	200	{
cf98d2b6	201	u64 flag = level >= 0 ? val & pg_level[level].mask : 0;
e54e30bc CL	202	u64 pa = val & PTE_RPN_MASK;
	203
	204	st->level = level;
	205	st->current_flags = flag;
	206	st->start_address = addr;
	207	st->start_pa = pa;
e54e30bc CL	208
	209	while (addr >= st->marker[1].start_address) {
	210	st->marker++;
	211	pt_dump_seq_printf(st->seq, "---[ %s ]---\n", st->marker->name);
	212	}
	213	}
	214
e0847283	215	static void note_page(struct ptdump_state *pt_st, unsigned long addr, int level, u64 val)
8eb07b18	216	{
cf98d2b6	217	u64 flag = level >= 0 ? val & pg_level[level].mask : 0;
e0847283	218	struct pg_state *st = container_of(pt_st, struct pg_state, ptdump);
aaa22952	219
8eb07b18	220	/* At first no level is set */
cf98d2b6	221	if (st->level == -1) {
5f18cbdb	222	pt_dump_seq_printf(st->seq, "---[ %s ]---\n", st->marker->name);
64b87b0c	223	note_page_update_state(st, addr, level, val);
8eb07b18 RG	224	/*
	225	* Dump the section of virtual memory when:
	226	* - the PTE flags from one entry to the next differs.
	227	* - we change levels in the tree.
	228	* - the address is in a different section of memory and is thus
	229	* used for a different purpose, regardless of the flags.
	230	*/
	231	} else if (flag != st->current_flags \|\| level != st->level \|\|
6ca6512c	232	addr >= st->marker[1].start_address) {
8eb07b18 RG	233
	234	/* Check the PTE flags */
	235	if (st->current_flags) {
453d87f6	236	note_prot_wx(st, addr);
8eb07b18 RG	237	dump_addr(st, addr);
	238
	239	/* Dump all the flags */
	240	if (pg_level[st->level].flag)
	241	dump_flag_info(st, pg_level[st->level].flag,
	242	st->current_flags,
	243	pg_level[st->level].num);
	244
5f18cbdb	245	pt_dump_seq_putc(st->seq, '\n');
8eb07b18 RG	246	}
	247
	248	/*
	249	* Address indicates we have passed the end of the
	250	* current section of virtual memory
	251	*/
64b87b0c	252	note_page_update_state(st, addr, level, val);
8eb07b18 RG	253	}
	254	}
	255
8eb07b18 RG	256	static void populate_markers(void)
8eb07b18 RG	257	{
6c01bbd2 CL	258	int i = 0;
6c01bbd2 CL	259
b6be1bb7	260	#ifdef CONFIG_PPC64
6c01bbd2	261	address_markers[i++].start_address = PAGE_OFFSET;
b6be1bb7 CL	262	#else
b6be1bb7 CL	263	address_markers[i++].start_address = TASK_SIZE;
6ca05532 CL	264	#endif
	265	#ifdef MODULES_VADDR
	266	address_markers[i++].start_address = MODULES_VADDR;
	267	address_markers[i++].start_address = MODULES_END;
b6be1bb7	268	#endif
6c01bbd2 CL	269	address_markers[i++].start_address = VMALLOC_START;
	270	address_markers[i++].start_address = VMALLOC_END;
	271	#ifdef CONFIG_PPC64
	272	address_markers[i++].start_address = ISA_IO_BASE;
	273	address_markers[i++].start_address = ISA_IO_END;
	274	address_markers[i++].start_address = PHB_IO_BASE;
	275	address_markers[i++].start_address = PHB_IO_END;
	276	address_markers[i++].start_address = IOREMAP_BASE;
	277	address_markers[i++].start_address = IOREMAP_END;
0034d395	278	/* What is the ifdef about? */
4e003747	279	#ifdef CONFIG_PPC_BOOK3S_64
0034d395	280	address_markers[i++].start_address = H_VMEMMAP_START;
8eb07b18	281	#else
6c01bbd2 CL	282	address_markers[i++].start_address = VMEMMAP_BASE;
	283	#endif
	284	#else /* !CONFIG_PPC64 */
	285	address_markers[i++].start_address = ioremap_bot;
	286	address_markers[i++].start_address = IOREMAP_TOP;
6c01bbd2 CL	287	#ifdef CONFIG_HIGHMEM
	288	address_markers[i++].start_address = PKMAP_BASE;
	289	address_markers[i++].start_address = PKMAP_ADDR(LAST_PKMAP);
8eb07b18	290	#endif
6c01bbd2 CL	291	address_markers[i++].start_address = FIXADDR_START;
6c01bbd2 CL	292	address_markers[i++].start_address = FIXADDR_TOP;
41b7a347	293	#endif /* CONFIG_PPC64 */
b4abe38f CL	294	#ifdef CONFIG_KASAN
	295	address_markers[i++].start_address = KASAN_SHADOW_START;
	296	address_markers[i++].start_address = KASAN_SHADOW_END;
	297	#endif
8eb07b18 RG	298	}
	299
	300	static int ptdump_show(struct seq_file m, void v)
	301	{
	302	struct pg_state st = {
	303	.seq = m,
8eb07b18	304	.marker = address_markers,
cf98d2b6	305	.level = -1,
e0847283 CL	306	.ptdump = {
	307	.note_page = note_page,
	308	.range = ptdump_range,
	309	}
8eb07b18	310	};
0d923962	311
8eb07b18	312	/* Traverse kernel page tables */
e0847283	313	ptdump_walk_pgd(&st.ptdump, &init_mm, NULL);
8eb07b18 RG	314	return 0;
	315	}
	316
11f27a7f	317	DEFINE_SHOW_ATTRIBUTE(ptdump);
8eb07b18	318
c13f2b2b	319	static void __init build_pgtable_complete_mask(void)
8eb07b18 RG	320	{
	321	unsigned int i, j;
	322
	323	for (i = 0; i < ARRAY_SIZE(pg_level); i++)
	324	if (pg_level[i].flag)
	325	for (j = 0; j < pg_level[i].num; j++)
	326	pg_level[i].mask \|= pg_level[i].flag[j].mask;
	327	}
	328
e0847283	329	#ifdef CONFIG_DEBUG_WX
453d87f6 RC	330	void ptdump_check_wx(void)
	331	{
	332	struct pg_state st = {
	333	.seq = NULL,
e0847283 CL	334	.marker = (struct addr_marker[]) {
	335	{ 0, NULL},
	336	{ -1, NULL},
	337	},
cf98d2b6	338	.level = -1,
453d87f6	339	.check_wx = true,
e0847283 CL	340	.ptdump = {
	341	.note_page = note_page,
	342	.range = ptdump_range,
	343	}
453d87f6 RC	344	};
453d87f6 RC	345
e0847283	346	ptdump_walk_pgd(&st.ptdump, &init_mm, NULL);
453d87f6 RC	347
	348	if (st.wx_pages)
	349	pr_warn("Checked W+X mappings: FAILED, %lu W+X pages found\n",
	350	st.wx_pages);
	351	else
	352	pr_info("Checked W+X mappings: passed, no W+X pages found\n");
	353	}
	354	#endif
	355
e0847283	356	static int __init ptdump_init(void)
8eb07b18	357	{
e0847283 CL	358	#ifdef CONFIG_PPC64
	359	if (!radix_enabled())
	360	ptdump_range[0].start = KERN_VIRT_START;
	361	else
	362	ptdump_range[0].start = PAGE_OFFSET;
b14b8b1e ME	363
b14b8b1e ME	364	ptdump_range[0].end = PAGE_OFFSET + (PGDIR_SIZE * PTRS_PER_PGD);
e0847283 CL	365	#endif
e0847283 CL	366
8eb07b18 RG	367	populate_markers();
8eb07b18 RG	368	build_pgtable_complete_mask();
e0847283 CL	369
	370	if (IS_ENABLED(CONFIG_PTDUMP_DEBUGFS))
	371	debugfs_create_file("kernel_page_tables", 0400, NULL, NULL, &ptdump_fops);
	372
f3c05201	373	return 0;
8eb07b18 RG	374	}
8eb07b18 RG	375	device_initcall(ptdump_init);