diff options
| -rw-r--r-- | arch/arm/include/asm/elf.h | 4 | ||||
| -rw-r--r-- | arch/arm/include/asm/mmu_context.h | 29 | ||||
| -rw-r--r-- | arch/arm/kernel/process.c | 21 |
3 files changed, 53 insertions, 1 deletions
diff --git a/arch/arm/include/asm/elf.h b/arch/arm/include/asm/elf.h index 5747a8baa413..8bb66bca2e3e 100644 --- a/arch/arm/include/asm/elf.h +++ b/arch/arm/include/asm/elf.h @@ -127,4 +127,8 @@ struct mm_struct; extern unsigned long arch_randomize_brk(struct mm_struct *mm); #define arch_randomize_brk arch_randomize_brk +extern int vectors_user_mapping(void); +#define arch_setup_additional_pages(bprm, uses_interp) vectors_user_mapping() +#define ARCH_HAS_SETUP_ADDITIONAL_PAGES + #endif diff --git a/arch/arm/include/asm/mmu_context.h b/arch/arm/include/asm/mmu_context.h index a0b3cac0547c..71605d9f8e42 100644 --- a/arch/arm/include/asm/mmu_context.h +++ b/arch/arm/include/asm/mmu_context.h @@ -18,7 +18,6 @@ #include <asm/cacheflush.h> #include <asm/cachetype.h> #include <asm/proc-fns.h> -#include <asm-generic/mm_hooks.h> void __check_kvm_seq(struct mm_struct *mm); @@ -134,4 +133,32 @@ switch_mm(struct mm_struct *prev, struct mm_struct *next, #define deactivate_mm(tsk,mm) do { } while (0) #define activate_mm(prev,next) switch_mm(prev, next, NULL) +/* + * We are inserting a "fake" vma for the user-accessible vector page so + * gdb and friends can get to it through ptrace and /proc/<pid>/mem. + * But we also want to remove it before the generic code gets to see it + * during process exit or the unmapping of it would cause total havoc. + * (the macro is used as remove_vma() is static to mm/mmap.c) + */ +#define arch_exit_mmap(mm) \ +do { \ + struct vm_area_struct *high_vma = find_vma(mm, 0xffff0000); \ + if (high_vma) { \ + BUG_ON(high_vma->vm_next); /* it should be last */ \ + if (high_vma->vm_prev) \ + high_vma->vm_prev->vm_next = NULL; \ + else \ + mm->mmap = NULL; \ + rb_erase(&high_vma->vm_rb, &mm->mm_rb); \ + mm->mmap_cache = NULL; \ + mm->map_count--; \ + remove_vma(high_vma); \ + } \ +} while (0) + +static inline void arch_dup_mmap(struct mm_struct *oldmm, + struct mm_struct *mm) +{ +} + #endif diff --git a/arch/arm/kernel/process.c b/arch/arm/kernel/process.c index 401e38be1f78..66ac9c926200 100644 --- a/arch/arm/kernel/process.c +++ b/arch/arm/kernel/process.c @@ -458,3 +458,24 @@ unsigned long arch_randomize_brk(struct mm_struct *mm) unsigned long range_end = mm->brk + 0x02000000; return randomize_range(mm->brk, range_end, 0) ? : mm->brk; } + +/* + * The vectors page is always readable from user space for the + * atomic helpers and the signal restart code. Let's declare a mapping + * for it so it is visible through ptrace and /proc/<pid>/mem. + */ + +int vectors_user_mapping(void) +{ + struct mm_struct *mm = current->mm; + return install_special_mapping(mm, 0xffff0000, PAGE_SIZE, + VM_READ | VM_EXEC | + VM_MAYREAD | VM_MAYEXEC | + VM_ALWAYSDUMP | VM_RESERVED, + NULL); +} + +const char *arch_vma_name(struct vm_area_struct *vma) +{ + return (vma->vm_start == 0xffff0000) ? "[vectors]" : NULL; +} |