diff options
Diffstat (limited to 'arch/arm/mm/init.c')
| -rw-r--r-- | arch/arm/mm/init.c | 117 |
1 files changed, 77 insertions, 40 deletions
diff --git a/arch/arm/mm/init.c b/arch/arm/mm/init.c index 8a63b4cdc0f2..370581aeb871 100644 --- a/arch/arm/mm/init.c +++ b/arch/arm/mm/init.c @@ -22,6 +22,7 @@ #include <linux/memblock.h> #include <linux/dma-contiguous.h> #include <linux/sizes.h> +#include <linux/stop_machine.h> #include <asm/cp15.h> #include <asm/mach-types.h> @@ -191,7 +192,7 @@ static void __init zone_sizes_init(unsigned long min, unsigned long max_low, #ifdef CONFIG_HAVE_ARCH_PFN_VALID int pfn_valid(unsigned long pfn) { - return memblock_is_memory(__pfn_to_phys(pfn)); + return memblock_is_map_memory(__pfn_to_phys(pfn)); } EXPORT_SYMBOL(pfn_valid); #endif @@ -432,6 +433,9 @@ static void __init free_highpages(void) if (end <= max_low) continue; + if (memblock_is_nomap(mem)) + continue; + /* Truncate partial highmem entries */ if (start < max_low) start = max_low; @@ -568,8 +572,9 @@ void __init mem_init(void) } } -#ifdef CONFIG_ARM_KERNMEM_PERMS +#ifdef CONFIG_DEBUG_RODATA struct section_perm { + const char *name; unsigned long start; unsigned long end; pmdval_t mask; @@ -577,9 +582,13 @@ struct section_perm { pmdval_t clear; }; +/* First section-aligned location at or after __start_rodata. */ +extern char __start_rodata_section_aligned[]; + static struct section_perm nx_perms[] = { /* Make pages tables, etc before _stext RW (set NX). */ { + .name = "pre-text NX", .start = PAGE_OFFSET, .end = (unsigned long)_stext, .mask = ~PMD_SECT_XN, @@ -587,26 +596,26 @@ static struct section_perm nx_perms[] = { }, /* Make init RW (set NX). */ { + .name = "init NX", .start = (unsigned long)__init_begin, .end = (unsigned long)_sdata, .mask = ~PMD_SECT_XN, .prot = PMD_SECT_XN, }, -#ifdef CONFIG_DEBUG_RODATA /* Make rodata NX (set RO in ro_perms below). */ { - .start = (unsigned long)__start_rodata, + .name = "rodata NX", + .start = (unsigned long)__start_rodata_section_aligned, .end = (unsigned long)__init_begin, .mask = ~PMD_SECT_XN, .prot = PMD_SECT_XN, }, -#endif }; -#ifdef CONFIG_DEBUG_RODATA static struct section_perm ro_perms[] = { /* Make kernel code and rodata RX (set RO). */ { + .name = "text/rodata RO", .start = (unsigned long)_stext, .end = (unsigned long)__init_begin, #ifdef CONFIG_ARM_LPAE @@ -619,7 +628,6 @@ static struct section_perm ro_perms[] = { #endif }, }; -#endif /* * Updates section permissions only for the current mm (sections are @@ -627,12 +635,10 @@ static struct section_perm ro_perms[] = { * safe to be called with preemption disabled, as under stop_machine(). */ static inline void section_update(unsigned long addr, pmdval_t mask, - pmdval_t prot) + pmdval_t prot, struct mm_struct *mm) { - struct mm_struct *mm; pmd_t *pmd; - mm = current->active_mm; pmd = pmd_offset(pud_offset(pgd_offset(mm, addr), addr), addr); #ifdef CONFIG_ARM_LPAE @@ -656,55 +662,86 @@ static inline bool arch_has_strict_perms(void) return !!(get_cr() & CR_XP); } -#define set_section_perms(perms, field) { \ - size_t i; \ - unsigned long addr; \ - \ - if (!arch_has_strict_perms()) \ - return; \ - \ - for (i = 0; i < ARRAY_SIZE(perms); i++) { \ - if (!IS_ALIGNED(perms[i].start, SECTION_SIZE) || \ - !IS_ALIGNED(perms[i].end, SECTION_SIZE)) { \ - pr_err("BUG: section %lx-%lx not aligned to %lx\n", \ - perms[i].start, perms[i].end, \ - SECTION_SIZE); \ - continue; \ - } \ - \ - for (addr = perms[i].start; \ - addr < perms[i].end; \ - addr += SECTION_SIZE) \ - section_update(addr, perms[i].mask, \ - perms[i].field); \ - } \ +void set_section_perms(struct section_perm *perms, int n, bool set, + struct mm_struct *mm) +{ + size_t i; + unsigned long addr; + + if (!arch_has_strict_perms()) + return; + + for (i = 0; i < n; i++) { + if (!IS_ALIGNED(perms[i].start, SECTION_SIZE) || + !IS_ALIGNED(perms[i].end, SECTION_SIZE)) { + pr_err("BUG: %s section %lx-%lx not aligned to %lx\n", + perms[i].name, perms[i].start, perms[i].end, + SECTION_SIZE); + continue; + } + + for (addr = perms[i].start; + addr < perms[i].end; + addr += SECTION_SIZE) + section_update(addr, perms[i].mask, + set ? perms[i].prot : perms[i].clear, mm); + } + +} + +static void update_sections_early(struct section_perm perms[], int n) +{ + struct task_struct *t, *s; + + read_lock(&tasklist_lock); + for_each_process(t) { + if (t->flags & PF_KTHREAD) + continue; + for_each_thread(t, s) + set_section_perms(perms, n, true, s->mm); + } + read_unlock(&tasklist_lock); + set_section_perms(perms, n, true, current->active_mm); + set_section_perms(perms, n, true, &init_mm); } -static inline void fix_kernmem_perms(void) +int __fix_kernmem_perms(void *unused) { - set_section_perms(nx_perms, prot); + update_sections_early(nx_perms, ARRAY_SIZE(nx_perms)); + return 0; +} + +void fix_kernmem_perms(void) +{ + stop_machine(__fix_kernmem_perms, NULL, NULL); +} + +int __mark_rodata_ro(void *unused) +{ + update_sections_early(ro_perms, ARRAY_SIZE(ro_perms)); + return 0; } -#ifdef CONFIG_DEBUG_RODATA void mark_rodata_ro(void) { - set_section_perms(ro_perms, prot); + stop_machine(__mark_rodata_ro, NULL, NULL); } void set_kernel_text_rw(void) { - set_section_perms(ro_perms, clear); + set_section_perms(ro_perms, ARRAY_SIZE(ro_perms), false, + current->active_mm); } void set_kernel_text_ro(void) { - set_section_perms(ro_perms, prot); + set_section_perms(ro_perms, ARRAY_SIZE(ro_perms), true, + current->active_mm); } -#endif /* CONFIG_DEBUG_RODATA */ #else static inline void fix_kernmem_perms(void) { } -#endif /* CONFIG_ARM_KERNMEM_PERMS */ +#endif /* CONFIG_DEBUG_RODATA */ void free_tcmmem(void) { |