* [PATCH v3 0/2] RISC-V page table dumper @ 2020-03-12 2:58 Zong Li 2020-03-12 2:58 ` Zong Li 2020-03-12 2:58 ` [PATCH v3 2/2] riscv: Use macro definition instead of magic number Zong Li 0 siblings, 2 replies; 4+ messages in thread From: Zong Li @ 2020-03-12 2:58 UTC (permalink / raw) To: palmer, paul.walmsley, aou, linux-riscv, linux-kernel; +Cc: Zong Li This patch supports dumping page tables, and it's implemented on top of the generic page table dumper patch set. Changed in v3: - Modify warning message. Changed in v2: - Remove unnecessary #ifdef directive. Zong Li (2): riscv: Add support to dump the kernel page tables riscv: Use macro definition instead of magic number arch/riscv/Kconfig | 1 + arch/riscv/include/asm/kasan.h | 2 +- arch/riscv/include/asm/pgtable.h | 10 + arch/riscv/include/asm/ptdump.h | 11 ++ arch/riscv/mm/Makefile | 1 + arch/riscv/mm/ptdump.c | 317 +++++++++++++++++++++++++++++++ 6 files changed, 341 insertions(+), 1 deletion(-) create mode 100644 arch/riscv/include/asm/ptdump.h create mode 100644 arch/riscv/mm/ptdump.c -- 2.25.1 ^ permalink raw reply [flat|nested] 4+ messages in thread
* [PATCH v3 1/2] riscv: Add support to dump the kernel page tables 2020-03-12 2:58 [PATCH v3 0/2] RISC-V page table dumper Zong Li @ 2020-03-12 2:58 ` Zong Li 2020-03-12 2:58 ` [PATCH v3 2/2] riscv: Use macro definition instead of magic number Zong Li 1 sibling, 0 replies; 4+ messages in thread From: Zong Li @ 2020-03-12 2:58 UTC (permalink / raw) To: palmer, paul.walmsley, aou, linux-riscv, linux-kernel Cc: Zong Li, Alexandre Ghiti In a similar manner to arm64, x86, powerpc, etc., it can traverse all page tables, and dump the page table layout with the memory types and permissions. Add a debugfs file at /sys/kernel/debug/kernel_page_tables to export the page table layout to userspace. Signed-off-by: Zong Li <zong.li@sifive.com> Tested-by: Alexandre Ghiti <alex@ghiti.fr> --- arch/riscv/Kconfig | 1 + arch/riscv/include/asm/pgtable.h | 10 + arch/riscv/include/asm/ptdump.h | 11 ++ arch/riscv/mm/Makefile | 1 + arch/riscv/mm/ptdump.c | 317 +++++++++++++++++++++++++++++++ 5 files changed, 340 insertions(+) create mode 100644 arch/riscv/include/asm/ptdump.h create mode 100644 arch/riscv/mm/ptdump.c diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig index 1a3b5a5276be..735b91014f79 100644 --- a/arch/riscv/Kconfig +++ b/arch/riscv/Kconfig @@ -29,6 +29,7 @@ config RISCV select GENERIC_SMP_IDLE_THREAD select GENERIC_ATOMIC64 if !64BIT select GENERIC_IOREMAP + select GENERIC_PTDUMP if MMU select HAVE_ARCH_AUDITSYSCALL select HAVE_ARCH_SECCOMP_FILTER select HAVE_ASM_MODVERSIONS diff --git a/arch/riscv/include/asm/pgtable.h b/arch/riscv/include/asm/pgtable.h index e43041519edd..ac353e44f80c 100644 --- a/arch/riscv/include/asm/pgtable.h +++ b/arch/riscv/include/asm/pgtable.h @@ -444,6 +444,16 @@ static inline int ptep_clear_flush_young(struct vm_area_struct *vma, #endif #define FIXADDR_START (FIXADDR_TOP - FIXADDR_SIZE) +/* + * In the RV64 Linux scheme, we give the user half of the virtual-address space + * and give the kernel the other (upper) half. + */ +#ifdef CONFIG_64BIT +#define KERN_VIRT_START (-(BIT(CONFIG_VA_BITS)) + TASK_SIZE) +#else +#define KERN_VIRT_START FIXADDR_START +#endif + /* * Task size is 0x4000000000 for RV64 or 0x9fc00000 for RV32. * Note that PGDIR_SIZE must evenly divide TASK_SIZE. diff --git a/arch/riscv/include/asm/ptdump.h b/arch/riscv/include/asm/ptdump.h new file mode 100644 index 000000000000..e29af7191909 --- /dev/null +++ b/arch/riscv/include/asm/ptdump.h @@ -0,0 +1,11 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright (C) 2019 SiFive + */ + +#ifndef _ASM_RISCV_PTDUMP_H +#define _ASM_RISCV_PTDUMP_H + +void ptdump_check_wx(void); + +#endif /* _ASM_RISCV_PTDUMP_H */ diff --git a/arch/riscv/mm/Makefile b/arch/riscv/mm/Makefile index 50b7af58c566..814e16a8d68a 100644 --- a/arch/riscv/mm/Makefile +++ b/arch/riscv/mm/Makefile @@ -15,6 +15,7 @@ ifeq ($(CONFIG_MMU),y) obj-$(CONFIG_SMP) += tlbflush.o endif obj-$(CONFIG_HUGETLB_PAGE) += hugetlbpage.o +obj-$(CONFIG_PTDUMP_CORE) += ptdump.o obj-$(CONFIG_KASAN) += kasan_init.o ifdef CONFIG_KASAN diff --git a/arch/riscv/mm/ptdump.c b/arch/riscv/mm/ptdump.c new file mode 100644 index 000000000000..7eab76a93106 --- /dev/null +++ b/arch/riscv/mm/ptdump.c @@ -0,0 +1,317 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2019 SiFive + */ + +#include <linux/init.h> +#include <linux/debugfs.h> +#include <linux/seq_file.h> +#include <linux/ptdump.h> + +#include <asm/ptdump.h> +#include <asm/pgtable.h> +#include <asm/kasan.h> + +#define pt_dump_seq_printf(m, fmt, args...) \ +({ \ + if (m) \ + seq_printf(m, fmt, ##args); \ +}) + +#define pt_dump_seq_puts(m, fmt) \ +({ \ + if (m) \ + seq_printf(m, fmt); \ +}) + +/* + * 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. + */ +struct pg_state { + struct ptdump_state ptdump; + struct seq_file *seq; + const struct addr_marker *marker; + unsigned long start_address; + unsigned long start_pa; + unsigned long last_pa; + int level; + u64 current_prot; + bool check_wx; + unsigned long wx_pages; +}; + +/* Address marker */ +struct addr_marker { + unsigned long start_address; + const char *name; +}; + +static struct addr_marker address_markers[] = { +#ifdef CONFIG_KASAN + {KASAN_SHADOW_START, "Kasan shadow start"}, + {KASAN_SHADOW_END, "Kasan shadow end"}, +#endif + {FIXADDR_START, "Fixmap start"}, + {FIXADDR_TOP, "Fixmap end"}, + {PCI_IO_START, "PCI I/O start"}, + {PCI_IO_END, "PCI I/O end"}, +#ifdef CONFIG_SPARSEMEM_VMEMMAP + {VMEMMAP_START, "vmemmap start"}, + {VMEMMAP_END, "vmemmap end"}, +#endif + {VMALLOC_START, "vmalloc() area"}, + {VMALLOC_END, "vmalloc() end"}, + {PAGE_OFFSET, "Linear mapping"}, + {-1, NULL}, +}; + +/* Page Table Entry */ +struct prot_bits { + u64 mask; + u64 val; + const char *set; + const char *clear; +}; + +static const struct prot_bits pte_bits[] = { + { + .mask = _PAGE_SOFT, + .val = _PAGE_SOFT, + .set = "RSW", + .clear = " ", + }, { + .mask = _PAGE_DIRTY, + .val = _PAGE_DIRTY, + .set = "D", + .clear = ".", + }, { + .mask = _PAGE_ACCESSED, + .val = _PAGE_ACCESSED, + .set = "A", + .clear = ".", + }, { + .mask = _PAGE_GLOBAL, + .val = _PAGE_GLOBAL, + .set = "G", + .clear = ".", + }, { + .mask = _PAGE_USER, + .val = _PAGE_USER, + .set = "U", + .clear = ".", + }, { + .mask = _PAGE_EXEC, + .val = _PAGE_EXEC, + .set = "X", + .clear = ".", + }, { + .mask = _PAGE_WRITE, + .val = _PAGE_WRITE, + .set = "W", + .clear = ".", + }, { + .mask = _PAGE_READ, + .val = _PAGE_READ, + .set = "R", + .clear = ".", + }, { + .mask = _PAGE_PRESENT, + .val = _PAGE_PRESENT, + .set = "V", + .clear = ".", + } +}; + +/* Page Level */ +struct pg_level { + const char *name; + u64 mask; +}; + +static struct pg_level pg_level[] = { + { /* pgd */ + .name = "PGD", + }, { /* p4d */ + .name = (CONFIG_PGTABLE_LEVELS > 4) ? "P4D" : "PGD", + }, { /* pud */ + .name = (CONFIG_PGTABLE_LEVELS > 3) ? "PUD" : "PGD", + }, { /* pmd */ + .name = (CONFIG_PGTABLE_LEVELS > 2) ? "PMD" : "PGD", + }, { /* pte */ + .name = "PTE", + }, +}; + +static void dump_prot(struct pg_state *st) +{ + unsigned int i; + + for (i = 0; i < ARRAY_SIZE(pte_bits); i++) { + const char *s; + + if ((st->current_prot & pte_bits[i].mask) == pte_bits[i].val) + s = pte_bits[i].set; + else + s = pte_bits[i].clear; + + if (s) + pt_dump_seq_printf(st->seq, " %s", s); + } +} + +#ifdef CONFIG_64BIT +#define ADDR_FORMAT "0x%016lx" +#else +#define ADDR_FORMAT "0x%08lx" +#endif +static void dump_addr(struct pg_state *st, unsigned long addr) +{ + static const char units[] = "KMGTPE"; + const char *unit = units; + unsigned long delta; + + pt_dump_seq_printf(st->seq, ADDR_FORMAT "-" ADDR_FORMAT " ", + st->start_address, addr); + + pt_dump_seq_printf(st->seq, " " ADDR_FORMAT " ", st->start_pa); + delta = (addr - st->start_address) >> 10; + + while (!(delta & 1023) && unit[1]) { + delta >>= 10; + unit++; + } + + pt_dump_seq_printf(st->seq, "%9lu%c %s", delta, *unit, + pg_level[st->level].name); +} + +static void note_prot_wx(struct pg_state *st, unsigned long addr) +{ + if (!st->check_wx) + return; + + if ((st->current_prot & (_PAGE_WRITE | _PAGE_EXEC)) != + (_PAGE_WRITE | _PAGE_EXEC)) + return; + + WARN_ONCE(1, "riscv/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(struct ptdump_state *pt_st, unsigned long addr, + int level, unsigned long val) +{ + struct pg_state *st = container_of(pt_st, struct pg_state, ptdump); + u64 pa = PFN_PHYS(pte_pfn(__pte(val))); + u64 prot = 0; + + if (level >= 0) + prot = val & pg_level[level].mask; + + if (st->level == -1) { + st->level = level; + st->current_prot = prot; + st->start_address = addr; + st->start_pa = pa; + st->last_pa = pa; + pt_dump_seq_printf(st->seq, "---[ %s ]---\n", st->marker->name); + } else if (prot != st->current_prot || + level != st->level || addr >= st->marker[1].start_address) { + if (st->current_prot) { + note_prot_wx(st, addr); + dump_addr(st, addr); + dump_prot(st); + pt_dump_seq_puts(st->seq, "\n"); + } + + while (addr >= st->marker[1].start_address) { + st->marker++; + pt_dump_seq_printf(st->seq, "---[ %s ]---\n", + st->marker->name); + } + + st->start_address = addr; + st->start_pa = pa; + st->last_pa = pa; + st->current_prot = prot; + st->level = level; + } else { + st->last_pa = pa; + } +} + +static void ptdump_walk(struct seq_file *s) +{ + struct pg_state st = { + .seq = s, + .marker = address_markers, + .level = -1, + .ptdump = { + .note_page = note_page, + .range = (struct ptdump_range[]) { + {KERN_VIRT_START, ULONG_MAX}, + {0, 0} + } + } + }; + + ptdump_walk_pgd(&st.ptdump, &init_mm, NULL); +} + +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 = (struct ptdump_range[]) { + {KERN_VIRT_START, ULONG_MAX}, + {0, 0} + } + } + }; + + 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"); +} + +static int ptdump_show(struct seq_file *m, void *v) +{ + ptdump_walk(m); + + return 0; +} + +DEFINE_SHOW_ATTRIBUTE(ptdump); + +static int ptdump_init(void) +{ + unsigned int i, j; + + for (i = 0; i < ARRAY_SIZE(pg_level); i++) + 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, + &ptdump_fops); + + return 0; +} + +device_initcall(ptdump_init); -- 2.25.1 ^ permalink raw reply related [flat|nested] 4+ messages in thread
* [PATCH v3 1/2] riscv: Add support to dump the kernel page tables @ 2020-03-12 2:58 ` Zong Li 0 siblings, 0 replies; 4+ messages in thread From: Zong Li @ 2020-03-12 2:58 UTC (permalink / raw) To: palmer, paul.walmsley, aou, linux-riscv, linux-kernel Cc: Alexandre Ghiti, Zong Li In a similar manner to arm64, x86, powerpc, etc., it can traverse all page tables, and dump the page table layout with the memory types and permissions. Add a debugfs file at /sys/kernel/debug/kernel_page_tables to export the page table layout to userspace. Signed-off-by: Zong Li <zong.li@sifive.com> Tested-by: Alexandre Ghiti <alex@ghiti.fr> --- arch/riscv/Kconfig | 1 + arch/riscv/include/asm/pgtable.h | 10 + arch/riscv/include/asm/ptdump.h | 11 ++ arch/riscv/mm/Makefile | 1 + arch/riscv/mm/ptdump.c | 317 +++++++++++++++++++++++++++++++ 5 files changed, 340 insertions(+) create mode 100644 arch/riscv/include/asm/ptdump.h create mode 100644 arch/riscv/mm/ptdump.c diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig index 1a3b5a5276be..735b91014f79 100644 --- a/arch/riscv/Kconfig +++ b/arch/riscv/Kconfig @@ -29,6 +29,7 @@ config RISCV select GENERIC_SMP_IDLE_THREAD select GENERIC_ATOMIC64 if !64BIT select GENERIC_IOREMAP + select GENERIC_PTDUMP if MMU select HAVE_ARCH_AUDITSYSCALL select HAVE_ARCH_SECCOMP_FILTER select HAVE_ASM_MODVERSIONS diff --git a/arch/riscv/include/asm/pgtable.h b/arch/riscv/include/asm/pgtable.h index e43041519edd..ac353e44f80c 100644 --- a/arch/riscv/include/asm/pgtable.h +++ b/arch/riscv/include/asm/pgtable.h @@ -444,6 +444,16 @@ static inline int ptep_clear_flush_young(struct vm_area_struct *vma, #endif #define FIXADDR_START (FIXADDR_TOP - FIXADDR_SIZE) +/* + * In the RV64 Linux scheme, we give the user half of the virtual-address space + * and give the kernel the other (upper) half. + */ +#ifdef CONFIG_64BIT +#define KERN_VIRT_START (-(BIT(CONFIG_VA_BITS)) + TASK_SIZE) +#else +#define KERN_VIRT_START FIXADDR_START +#endif + /* * Task size is 0x4000000000 for RV64 or 0x9fc00000 for RV32. * Note that PGDIR_SIZE must evenly divide TASK_SIZE. diff --git a/arch/riscv/include/asm/ptdump.h b/arch/riscv/include/asm/ptdump.h new file mode 100644 index 000000000000..e29af7191909 --- /dev/null +++ b/arch/riscv/include/asm/ptdump.h @@ -0,0 +1,11 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright (C) 2019 SiFive + */ + +#ifndef _ASM_RISCV_PTDUMP_H +#define _ASM_RISCV_PTDUMP_H + +void ptdump_check_wx(void); + +#endif /* _ASM_RISCV_PTDUMP_H */ diff --git a/arch/riscv/mm/Makefile b/arch/riscv/mm/Makefile index 50b7af58c566..814e16a8d68a 100644 --- a/arch/riscv/mm/Makefile +++ b/arch/riscv/mm/Makefile @@ -15,6 +15,7 @@ ifeq ($(CONFIG_MMU),y) obj-$(CONFIG_SMP) += tlbflush.o endif obj-$(CONFIG_HUGETLB_PAGE) += hugetlbpage.o +obj-$(CONFIG_PTDUMP_CORE) += ptdump.o obj-$(CONFIG_KASAN) += kasan_init.o ifdef CONFIG_KASAN diff --git a/arch/riscv/mm/ptdump.c b/arch/riscv/mm/ptdump.c new file mode 100644 index 000000000000..7eab76a93106 --- /dev/null +++ b/arch/riscv/mm/ptdump.c @@ -0,0 +1,317 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2019 SiFive + */ + +#include <linux/init.h> +#include <linux/debugfs.h> +#include <linux/seq_file.h> +#include <linux/ptdump.h> + +#include <asm/ptdump.h> +#include <asm/pgtable.h> +#include <asm/kasan.h> + +#define pt_dump_seq_printf(m, fmt, args...) \ +({ \ + if (m) \ + seq_printf(m, fmt, ##args); \ +}) + +#define pt_dump_seq_puts(m, fmt) \ +({ \ + if (m) \ + seq_printf(m, fmt); \ +}) + +/* + * 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. + */ +struct pg_state { + struct ptdump_state ptdump; + struct seq_file *seq; + const struct addr_marker *marker; + unsigned long start_address; + unsigned long start_pa; + unsigned long last_pa; + int level; + u64 current_prot; + bool check_wx; + unsigned long wx_pages; +}; + +/* Address marker */ +struct addr_marker { + unsigned long start_address; + const char *name; +}; + +static struct addr_marker address_markers[] = { +#ifdef CONFIG_KASAN + {KASAN_SHADOW_START, "Kasan shadow start"}, + {KASAN_SHADOW_END, "Kasan shadow end"}, +#endif + {FIXADDR_START, "Fixmap start"}, + {FIXADDR_TOP, "Fixmap end"}, + {PCI_IO_START, "PCI I/O start"}, + {PCI_IO_END, "PCI I/O end"}, +#ifdef CONFIG_SPARSEMEM_VMEMMAP + {VMEMMAP_START, "vmemmap start"}, + {VMEMMAP_END, "vmemmap end"}, +#endif + {VMALLOC_START, "vmalloc() area"}, + {VMALLOC_END, "vmalloc() end"}, + {PAGE_OFFSET, "Linear mapping"}, + {-1, NULL}, +}; + +/* Page Table Entry */ +struct prot_bits { + u64 mask; + u64 val; + const char *set; + const char *clear; +}; + +static const struct prot_bits pte_bits[] = { + { + .mask = _PAGE_SOFT, + .val = _PAGE_SOFT, + .set = "RSW", + .clear = " ", + }, { + .mask = _PAGE_DIRTY, + .val = _PAGE_DIRTY, + .set = "D", + .clear = ".", + }, { + .mask = _PAGE_ACCESSED, + .val = _PAGE_ACCESSED, + .set = "A", + .clear = ".", + }, { + .mask = _PAGE_GLOBAL, + .val = _PAGE_GLOBAL, + .set = "G", + .clear = ".", + }, { + .mask = _PAGE_USER, + .val = _PAGE_USER, + .set = "U", + .clear = ".", + }, { + .mask = _PAGE_EXEC, + .val = _PAGE_EXEC, + .set = "X", + .clear = ".", + }, { + .mask = _PAGE_WRITE, + .val = _PAGE_WRITE, + .set = "W", + .clear = ".", + }, { + .mask = _PAGE_READ, + .val = _PAGE_READ, + .set = "R", + .clear = ".", + }, { + .mask = _PAGE_PRESENT, + .val = _PAGE_PRESENT, + .set = "V", + .clear = ".", + } +}; + +/* Page Level */ +struct pg_level { + const char *name; + u64 mask; +}; + +static struct pg_level pg_level[] = { + { /* pgd */ + .name = "PGD", + }, { /* p4d */ + .name = (CONFIG_PGTABLE_LEVELS > 4) ? "P4D" : "PGD", + }, { /* pud */ + .name = (CONFIG_PGTABLE_LEVELS > 3) ? "PUD" : "PGD", + }, { /* pmd */ + .name = (CONFIG_PGTABLE_LEVELS > 2) ? "PMD" : "PGD", + }, { /* pte */ + .name = "PTE", + }, +}; + +static void dump_prot(struct pg_state *st) +{ + unsigned int i; + + for (i = 0; i < ARRAY_SIZE(pte_bits); i++) { + const char *s; + + if ((st->current_prot & pte_bits[i].mask) == pte_bits[i].val) + s = pte_bits[i].set; + else + s = pte_bits[i].clear; + + if (s) + pt_dump_seq_printf(st->seq, " %s", s); + } +} + +#ifdef CONFIG_64BIT +#define ADDR_FORMAT "0x%016lx" +#else +#define ADDR_FORMAT "0x%08lx" +#endif +static void dump_addr(struct pg_state *st, unsigned long addr) +{ + static const char units[] = "KMGTPE"; + const char *unit = units; + unsigned long delta; + + pt_dump_seq_printf(st->seq, ADDR_FORMAT "-" ADDR_FORMAT " ", + st->start_address, addr); + + pt_dump_seq_printf(st->seq, " " ADDR_FORMAT " ", st->start_pa); + delta = (addr - st->start_address) >> 10; + + while (!(delta & 1023) && unit[1]) { + delta >>= 10; + unit++; + } + + pt_dump_seq_printf(st->seq, "%9lu%c %s", delta, *unit, + pg_level[st->level].name); +} + +static void note_prot_wx(struct pg_state *st, unsigned long addr) +{ + if (!st->check_wx) + return; + + if ((st->current_prot & (_PAGE_WRITE | _PAGE_EXEC)) != + (_PAGE_WRITE | _PAGE_EXEC)) + return; + + WARN_ONCE(1, "riscv/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(struct ptdump_state *pt_st, unsigned long addr, + int level, unsigned long val) +{ + struct pg_state *st = container_of(pt_st, struct pg_state, ptdump); + u64 pa = PFN_PHYS(pte_pfn(__pte(val))); + u64 prot = 0; + + if (level >= 0) + prot = val & pg_level[level].mask; + + if (st->level == -1) { + st->level = level; + st->current_prot = prot; + st->start_address = addr; + st->start_pa = pa; + st->last_pa = pa; + pt_dump_seq_printf(st->seq, "---[ %s ]---\n", st->marker->name); + } else if (prot != st->current_prot || + level != st->level || addr >= st->marker[1].start_address) { + if (st->current_prot) { + note_prot_wx(st, addr); + dump_addr(st, addr); + dump_prot(st); + pt_dump_seq_puts(st->seq, "\n"); + } + + while (addr >= st->marker[1].start_address) { + st->marker++; + pt_dump_seq_printf(st->seq, "---[ %s ]---\n", + st->marker->name); + } + + st->start_address = addr; + st->start_pa = pa; + st->last_pa = pa; + st->current_prot = prot; + st->level = level; + } else { + st->last_pa = pa; + } +} + +static void ptdump_walk(struct seq_file *s) +{ + struct pg_state st = { + .seq = s, + .marker = address_markers, + .level = -1, + .ptdump = { + .note_page = note_page, + .range = (struct ptdump_range[]) { + {KERN_VIRT_START, ULONG_MAX}, + {0, 0} + } + } + }; + + ptdump_walk_pgd(&st.ptdump, &init_mm, NULL); +} + +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 = (struct ptdump_range[]) { + {KERN_VIRT_START, ULONG_MAX}, + {0, 0} + } + } + }; + + 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"); +} + +static int ptdump_show(struct seq_file *m, void *v) +{ + ptdump_walk(m); + + return 0; +} + +DEFINE_SHOW_ATTRIBUTE(ptdump); + +static int ptdump_init(void) +{ + unsigned int i, j; + + for (i = 0; i < ARRAY_SIZE(pg_level); i++) + 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, + &ptdump_fops); + + return 0; +} + +device_initcall(ptdump_init); -- 2.25.1 ^ permalink raw reply related [flat|nested] 4+ messages in thread
* [PATCH v3 2/2] riscv: Use macro definition instead of magic number 2020-03-12 2:58 [PATCH v3 0/2] RISC-V page table dumper Zong Li 2020-03-12 2:58 ` Zong Li @ 2020-03-12 2:58 ` Zong Li 1 sibling, 0 replies; 4+ messages in thread From: Zong Li @ 2020-03-12 2:58 UTC (permalink / raw) To: palmer, paul.walmsley, aou, linux-riscv, linux-kernel; +Cc: Zong Li The KERN_VIRT_START defines the start virtual address of kernel space. Use this macro instead of magic number. Signed-off-by: Zong Li <zong.li@sifive.com> --- arch/riscv/include/asm/kasan.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/riscv/include/asm/kasan.h b/arch/riscv/include/asm/kasan.h index eee6e6588b12..b47045cb85ce 100644 --- a/arch/riscv/include/asm/kasan.h +++ b/arch/riscv/include/asm/kasan.h @@ -13,7 +13,7 @@ #define KASAN_SHADOW_SCALE_SHIFT 3 #define KASAN_SHADOW_SIZE (UL(1) << (38 - KASAN_SHADOW_SCALE_SHIFT)) -#define KASAN_SHADOW_START 0xffffffc000000000 /* 2^64 - 2^38 */ +#define KASAN_SHADOW_START KERN_VIRT_START /* 2^64 - 2^38 */ #define KASAN_SHADOW_END (KASAN_SHADOW_START + KASAN_SHADOW_SIZE) #define KASAN_SHADOW_OFFSET (KASAN_SHADOW_END - (1ULL << \ -- 2.25.1 ^ permalink raw reply related [flat|nested] 4+ messages in thread
end of thread, other threads:[~2020-03-12 2:58 UTC | newest] Thread overview: 4+ messages (download: mbox.gz / follow: Atom feed) -- links below jump to the message on this page -- 2020-03-12 2:58 [PATCH v3 0/2] RISC-V page table dumper Zong Li 2020-03-12 2:58 ` [PATCH v3 1/2] riscv: Add support to dump the kernel page tables Zong Li 2020-03-12 2:58 ` Zong Li 2020-03-12 2:58 ` [PATCH v3 2/2] riscv: Use macro definition instead of magic number Zong Li
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