Unverified Commit de22d210 authored by Atish Patra's avatar Atish Patra Committed by Palmer Dabbelt
Browse files

RISC-V: Add page table dump support for uefi 



Extend the current page table dump support in RISC-V to include efi
pages as well.

Here is the output of efi runtime page table mappings.

---[ UEFI runtime start ]---
0x0000000020002000-0x0000000020003000 0x00000000be732000 4K PTE D A . . . W R V
0x0000000020018000-0x0000000020019000 0x00000000be738000 4K PTE D A . . . W R V
0x000000002002c000-0x000000002002d000 0x00000000be73c000 4K PTE D A . . . W R V
0x0000000020031000-0x0000000020032000 0x00000000bff61000 4K PTE D A . . X W R V
---[ UEFI runtime end ]---

Signed-off-by: default avatarAtish Patra <atish.patra@wdc.com>
Reviewed-by: default avatarAnup Patel <anup@brainfault.org>
Signed-off-by: default avatarPalmer Dabbelt <palmerdabbelt@google.com>
parent b91540d5

arch/riscv/mm/ptdump.c

+42 −6
Original line number Diff line number Diff line
@@ -3,6 +3,7 @@ 
 * Copyright (C) 2019 SiFive

 */



#include <linux/efi.h>

#include <linux/init.h>

#include <linux/debugfs.h>

#include <linux/seq_file.h>
@@ -49,6 +50,14 @@ struct addr_marker { 
	const char *name;

};



/* Private information for debugfs */

struct ptd_mm_info {

	struct mm_struct		*mm;

	const struct addr_marker	*markers;

	unsigned long base_addr;

	unsigned long end;

};



static struct addr_marker address_markers[] = {

#ifdef CONFIG_KASAN

	{KASAN_SHADOW_START,	"Kasan shadow start"},
@@ -68,6 +77,28 @@ static struct addr_marker address_markers[] = { 
	{-1, NULL},

};



static struct ptd_mm_info kernel_ptd_info = {

	.mm		= &init_mm,

	.markers	= address_markers,

	.base_addr	= KERN_VIRT_START,

	.end		= ULONG_MAX,

};



#ifdef CONFIG_EFI

static struct addr_marker efi_addr_markers[] = {

		{ 0,		"UEFI runtime start" },

		{ SZ_1G,	"UEFI runtime end" },

		{ -1,		NULL }

};



static struct ptd_mm_info efi_ptd_info = {

	.mm		= &efi_mm,

	.markers	= efi_addr_markers,

	.base_addr	= 0,

	.end		= SZ_2G,

};

#endif



/* Page Table Entry */

struct prot_bits {

	u64 mask;
@@ -245,22 +276,22 @@ static void note_page(struct ptdump_state *pt_st, unsigned long addr, 
	}

}



static void ptdump_walk(struct seq_file *s)

static void ptdump_walk(struct seq_file *s, struct ptd_mm_info *pinfo)

{

	struct pg_state st = {

		.seq = s,

		.marker = address_markers,

		.marker = pinfo->markers,

		.level = -1,

		.ptdump = {

			.note_page = note_page,

			.range = (struct ptdump_range[]) {

				{KERN_VIRT_START, ULONG_MAX},

				{pinfo->base_addr, pinfo->end},

				{0, 0}

			}

		}

	};



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

	ptdump_walk_pgd(&st.ptdump, pinfo->mm, NULL);

}



void ptdump_check_wx(void)
@@ -293,7 +324,7 @@ void ptdump_check_wx(void) 


static int ptdump_show(struct seq_file *m, void *v)

{

	ptdump_walk(m);

	ptdump_walk(m, m->private);



	return 0;

}
@@ -308,8 +339,13 @@ static int ptdump_init(void) 
		for (j = 0; j < ARRAY_SIZE(pte_bits); j++)

			pg_level[i].mask |= pte_bits[j].mask;



	debugfs_create_file("kernel_page_tables", 0400, NULL, NULL,

	debugfs_create_file("kernel_page_tables", 0400, NULL, &kernel_ptd_info,

			    &ptdump_fops);

#ifdef CONFIG_EFI

	if (efi_enabled(EFI_RUNTIME_SERVICES))

		debugfs_create_file("efi_page_tables", 0400, NULL, &efi_ptd_info,

				    &ptdump_fops);

#endif



	return 0;

}

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