diff options
| author | Will Deacon <will.deacon@arm.com> | 2012-01-20 12:01:13 +0100 |
|---|---|---|
| committer | Russell King <rmk+kernel@arm.linux.org.uk> | 2012-03-24 09:38:51 +0000 |
| commit | f9d4861fc32b995b1616775614459b8f266c803c (patch) | |
| tree | 187d7bfa7ff0418f2762d38c9c553331e602faf1 /arch/arm/include | |
| parent | 195864cf3d6f5b6b743793bda3aaa2ff65d322ae (diff) | |
ARM: 7294/1: vectors: use gate_vma for vectors user mapping
The current user mapping for the vectors page is inserted as a `horrible
hack vma' into each task via arch_setup_additional_pages. This causes
problems with the MM subsystem and vm_normal_page, as described here:
https://lkml.org/lkml/2012/1/14/55
Following the suggestion from Hugh in the above thread, this patch uses
the gate_vma for the vectors user mapping, therefore consolidating
the horrible hack VMAs into one.
Acked-and-Tested-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Diffstat (limited to 'arch/arm/include')
| -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/include/asm/page.h | 2 |
3 files changed, 3 insertions, 32 deletions
diff --git a/arch/arm/include/asm/elf.h b/arch/arm/include/asm/elf.h index 0e9ce8d9686e..38050b1c4800 100644 --- a/arch/arm/include/asm/elf.h +++ b/arch/arm/include/asm/elf.h @@ -130,8 +130,4 @@ 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 71605d9f8e42..a0b3cac0547c 100644 --- a/arch/arm/include/asm/mmu_context.h +++ b/arch/arm/include/asm/mmu_context.h @@ -18,6 +18,7 @@ #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); @@ -133,32 +134,4 @@ 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/include/asm/page.h b/arch/arm/include/asm/page.h index 97b440c25c58..5838361c48b3 100644 --- a/arch/arm/include/asm/page.h +++ b/arch/arm/include/asm/page.h @@ -151,6 +151,8 @@ extern void __cpu_copy_user_highpage(struct page *to, struct page *from, #define clear_page(page) memset((void *)(page), 0, PAGE_SIZE) extern void copy_page(void *to, const void *from); +#define __HAVE_ARCH_GATE_AREA 1 + #ifdef CONFIG_ARM_LPAE #include <asm/pgtable-3level-types.h> #else |