Instead of providing our own callbacks for walking the page tables, switch to using the generic version instead. Signed-off-by: Steven Price <steven.price@xxxxxxx> --- arch/arm64/Kconfig | 1 + arch/arm64/Kconfig.debug | 19 +----- arch/arm64/include/asm/ptdump.h | 8 +-- arch/arm64/mm/Makefile | 4 +- arch/arm64/mm/dump.c | 104 +++++++++----------------------- arch/arm64/mm/ptdump_debugfs.c | 2 +- 6 files changed, 37 insertions(+), 101 deletions(-) diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index 117b2541ef3d..4ff55b3ce8dc 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -97,6 +97,7 @@ config ARM64 select GENERIC_IRQ_SHOW select GENERIC_IRQ_SHOW_LEVEL select GENERIC_PCI_IOMAP + select GENERIC_PTDUMP select GENERIC_SCHED_CLOCK select GENERIC_SMP_IDLE_THREAD select GENERIC_STRNCPY_FROM_USER diff --git a/arch/arm64/Kconfig.debug b/arch/arm64/Kconfig.debug index 69c9170bdd24..570dba4d4a0e 100644 --- a/arch/arm64/Kconfig.debug +++ b/arch/arm64/Kconfig.debug @@ -1,21 +1,4 @@ -config ARM64_PTDUMP_CORE - def_bool n - -config ARM64_PTDUMP_DEBUGFS - bool "Export kernel pagetable layout to userspace via debugfs" - depends on DEBUG_KERNEL - select ARM64_PTDUMP_CORE - select DEBUG_FS - help - Say Y here if you want to show the kernel pagetable layout in a - debugfs file. This information is only useful for kernel developers - who are working in architecture specific areas of the kernel. - It is probably not a good idea to enable this feature in a production - kernel. - - If in doubt, say N. - config PID_IN_CONTEXTIDR bool "Write the current PID to the CONTEXTIDR register" help @@ -41,7 +24,7 @@ config ARM64_RANDOMIZE_TEXT_OFFSET config DEBUG_WX bool "Warn on W+X mappings at boot" - select ARM64_PTDUMP_CORE + select PTDUMP_CORE ---help--- Generate a warning if any W+X mappings are found at boot. diff --git a/arch/arm64/include/asm/ptdump.h b/arch/arm64/include/asm/ptdump.h index 9e948a93d26c..f8fecda7b61d 100644 --- a/arch/arm64/include/asm/ptdump.h +++ b/arch/arm64/include/asm/ptdump.h @@ -16,7 +16,7 @@ #ifndef __ASM_PTDUMP_H #define __ASM_PTDUMP_H -#ifdef CONFIG_ARM64_PTDUMP_CORE +#ifdef CONFIG_PTDUMP_CORE #include <linux/mm_types.h> #include <linux/seq_file.h> @@ -32,15 +32,15 @@ struct ptdump_info { unsigned long base_addr; }; -void ptdump_walk_pgd(struct seq_file *s, struct ptdump_info *info); -#ifdef CONFIG_ARM64_PTDUMP_DEBUGFS +void ptdump_walk(struct seq_file *s, struct ptdump_info *info); +#ifdef CONFIG_PTDUMP_DEBUGFS void ptdump_debugfs_register(struct ptdump_info *info, const char *name); #else static inline void ptdump_debugfs_register(struct ptdump_info *info, const char *name) { } #endif void ptdump_check_wx(void); -#endif /* CONFIG_ARM64_PTDUMP_CORE */ +#endif /* CONFIG_PTDUMP_CORE */ #ifdef CONFIG_DEBUG_WX #define debug_checkwx() ptdump_check_wx() diff --git a/arch/arm64/mm/Makefile b/arch/arm64/mm/Makefile index 849c1df3d214..d91030f0ffee 100644 --- a/arch/arm64/mm/Makefile +++ b/arch/arm64/mm/Makefile @@ -4,8 +4,8 @@ obj-y := dma-mapping.o extable.o fault.o init.o \ ioremap.o mmap.o pgd.o mmu.o \ context.o proc.o pageattr.o obj-$(CONFIG_HUGETLB_PAGE) += hugetlbpage.o -obj-$(CONFIG_ARM64_PTDUMP_CORE) += dump.o -obj-$(CONFIG_ARM64_PTDUMP_DEBUGFS) += ptdump_debugfs.o +obj-$(CONFIG_PTDUMP_CORE) += dump.o +obj-$(CONFIG_PTDUMP_DEBUGFS) += ptdump_debugfs.o obj-$(CONFIG_NUMA) += numa.o obj-$(CONFIG_DEBUG_VIRTUAL) += physaddr.o KASAN_SANITIZE_physaddr.o += n diff --git a/arch/arm64/mm/dump.c b/arch/arm64/mm/dump.c index ea20c1213498..e68df2ad8863 100644 --- a/arch/arm64/mm/dump.c +++ b/arch/arm64/mm/dump.c @@ -19,6 +19,7 @@ #include <linux/io.h> #include <linux/init.h> #include <linux/mm.h> +#include <linux/ptdump.h> #include <linux/sched.h> #include <linux/seq_file.h> @@ -69,6 +70,7 @@ static const struct addr_marker address_markers[] = { * 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; @@ -172,6 +174,10 @@ static struct pg_level pg_level[] = { .name = "PGD", .bits = pte_bits, .num = ARRAY_SIZE(pte_bits), + }, { /* p4d */ + .name = "P4D", + .bits = pte_bits, + .num = ARRAY_SIZE(pte_bits), }, { /* pud */ .name = (CONFIG_PGTABLE_LEVELS > 3) ? "PUD" : "PGD", .bits = pte_bits, @@ -234,9 +240,10 @@ static void note_prot_wx(struct pg_state *st, unsigned long addr) st->wx_pages += (addr - st->start_address) / PAGE_SIZE; } -static void note_page(struct pg_state *st, unsigned long addr, int level, - u64 val) +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); static const char units[] = "KMGTPE"; u64 prot = 0; @@ -289,83 +296,21 @@ static void note_page(struct pg_state *st, unsigned long addr, int level, } -static int pud_entry(pud_t *pud, unsigned long addr, - unsigned long next, struct mm_walk *walk) -{ - struct pg_state *st = walk->private; - pud_t val = READ_ONCE(*pud); - - if (pud_table(val)) - return 0; - - note_page(st, addr, 2, pud_val(val)); - - return 0; -} - -static int pmd_entry(pmd_t *pmd, unsigned long addr, - unsigned long next, struct mm_walk *walk) -{ - struct pg_state *st = walk->private; - pmd_t val = READ_ONCE(*pmd); - - if (pmd_table(val)) - return 0; - - note_page(st, addr, 3, pmd_val(val)); - - return 0; -} - -static int pte_entry(pte_t *pte, unsigned long addr, - unsigned long next, struct mm_walk *walk) -{ - struct pg_state *st = walk->private; - pte_t val = READ_ONCE(*pte); - - note_page(st, addr, 4, pte_val(val)); - - return 0; -} - -static int pte_hole(unsigned long addr, unsigned long next, - struct mm_walk *walk) -{ - struct pg_state *st = walk->private; - - note_page(st, addr, -1, 0); - - return 0; -} - -static void walk_pgd(struct pg_state *st, struct mm_struct *mm, - unsigned long start) -{ - struct mm_walk walk = { - .mm = mm, - .private = st, - .pud_entry = pud_entry, - .pmd_entry = pmd_entry, - .pte_entry = pte_entry, - .pte_hole = pte_hole - }; - down_read(&mm->mmap_sem); - walk_page_range(start, start | (((unsigned long)PTRS_PER_PGD << - PGDIR_SHIFT) - 1), - &walk); - up_read(&mm->mmap_sem); -} - -void ptdump_walk_pgd(struct seq_file *m, struct ptdump_info *info) +void ptdump_walk(struct seq_file *s, struct ptdump_info *info) { struct pg_state st = { - .seq = m, + .seq = s, .marker = info->markers, + .ptdump = { + .note_page = note_page, + .range = (struct ptdump_range[]){ + {info->base_addr, ~0UL}, + {0, 0} + } + } }; - walk_pgd(&st, info->mm, info->base_addr); - - note_page(&st, 0, 0, 0); + ptdump_walk_pgd(&st.ptdump, info->mm); } static void ptdump_initialize(void) @@ -393,10 +338,17 @@ void ptdump_check_wx(void) { -1, NULL}, }, .check_wx = true, + .ptdump = { + .note_page = note_page, + .range = (struct ptdump_range[]) { + {VA_START, ~0UL}, + {0, 0} + } + } }; - walk_pgd(&st, &init_mm, VA_START); - note_page(&st, 0, 0, 0); + ptdump_walk_pgd(&st.ptdump, &init_mm); + if (st.wx_pages || st.uxn_pages) pr_warn("Checked W+X mappings: FAILED, %lu W+X pages found, %lu non-UXN pages found\n", st.wx_pages, st.uxn_pages); diff --git a/arch/arm64/mm/ptdump_debugfs.c b/arch/arm64/mm/ptdump_debugfs.c index 064163f25592..1f2eae3e988b 100644 --- a/arch/arm64/mm/ptdump_debugfs.c +++ b/arch/arm64/mm/ptdump_debugfs.c @@ -7,7 +7,7 @@ static int ptdump_show(struct seq_file *m, void *v) { struct ptdump_info *info = m->private; - ptdump_walk_pgd(m, info); + ptdump_walk(m, info); return 0; } DEFINE_SHOW_ATTRIBUTE(ptdump); -- 2.20.1