path: root/mm
diff options
authorHugh Dickins <hughd@google.com>2013-04-29 15:07:44 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2013-04-29 15:54:34 -0700
commit6ee8630e02be6dd89926ca0fbc21af68b23dc087 (patch)
tree04c4cb8546541d59dac8d92ac1c7d7ee03ddc362 /mm
parentacb6d558f4c8fbacc8e774c9d7737220a3777882 (diff)
mm: allow arch code to control the user page table ceiling
On architectures where a pgd entry may be shared between user and kernel (e.g. ARM+LPAE), freeing page tables needs a ceiling other than 0. This patch introduces a generic USER_PGTABLES_CEILING that arch code can override. It is the responsibility of the arch code setting the ceiling to ensure the complete freeing of the page tables (usually in pgd_free()). [catalin.marinas@arm.com: commit log; shift_arg_pages(), asm-generic/pgtables.h changes] Signed-off-by: Hugh Dickins <hughd@google.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Cc: Russell King <linux@arm.linux.org.uk> Cc: <stable@vger.kernel.org> [3.3+] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm')
1 files changed, 2 insertions, 2 deletions
diff --git a/mm/mmap.c b/mm/mmap.c
index b2c363f7ae5..288958f05f1 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -2302,7 +2302,7 @@ static void unmap_region(struct mm_struct *mm,
unmap_vmas(&tlb, vma, start, end);
free_pgtables(&tlb, vma, prev ? prev->vm_end : FIRST_USER_ADDRESS,
- next ? next->vm_start : 0);
+ next ? next->vm_start : USER_PGTABLES_CEILING);
tlb_finish_mmu(&tlb, start, end);
@@ -2682,7 +2682,7 @@ void exit_mmap(struct mm_struct *mm)
/* Use -1 here to ensure all VMAs in the mm are unmapped */
unmap_vmas(&tlb, vma, 0, -1);
- free_pgtables(&tlb, vma, FIRST_USER_ADDRESS, 0);
+ free_pgtables(&tlb, vma, FIRST_USER_ADDRESS, USER_PGTABLES_CEILING);
tlb_finish_mmu(&tlb, 0, -1);