diff options
author | Chen, Kenneth W <kenneth.w.chen@intel.com> | 2006-10-11 04:20:46 -0400 |
---|---|---|
committer | Linus Torvalds <torvalds@g5.osdl.org> | 2006-10-11 14:14:15 -0400 |
commit | 502717f4e112b18d9c37753a32f675bec9f2838b (patch) | |
tree | 90e674229bbd7caa05e740dfe719cf8749d0eb27 /mm/hugetlb.c | |
parent | 97c7801cd5b0bb6a38c16108a496235474dc6310 (diff) |
[PATCH] hugetlb: fix linked list corruption in unmap_hugepage_range()
commit fe1668ae5bf0145014c71797febd9ad5670d5d05 causes kernel to oops with
libhugetlbfs test suite. The problem is that hugetlb pages can be shared
by multiple mappings. Multiple threads can fight over page->lru in the
unmap path and bad things happen. We now serialize __unmap_hugepage_range
to void concurrent linked list manipulation. Such serialization is also
needed for shared page table page on hugetlb area. This patch will fixed
the bug and also serve as a prepatch for shared page table.
Signed-off-by: Ken Chen <kenneth.w.chen@intel.com>
Cc: Hugh Dickins <hugh@veritas.com>
Cc: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'mm/hugetlb.c')
-rw-r--r-- | mm/hugetlb.c | 22 |
1 files changed, 20 insertions, 2 deletions
diff --git a/mm/hugetlb.c b/mm/hugetlb.c index 1d709ff528e..2dbec90dc3b 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c | |||
@@ -356,8 +356,8 @@ nomem: | |||
356 | return -ENOMEM; | 356 | return -ENOMEM; |
357 | } | 357 | } |
358 | 358 | ||
359 | void unmap_hugepage_range(struct vm_area_struct *vma, unsigned long start, | 359 | void __unmap_hugepage_range(struct vm_area_struct *vma, unsigned long start, |
360 | unsigned long end) | 360 | unsigned long end) |
361 | { | 361 | { |
362 | struct mm_struct *mm = vma->vm_mm; | 362 | struct mm_struct *mm = vma->vm_mm; |
363 | unsigned long address; | 363 | unsigned long address; |
@@ -398,6 +398,24 @@ void unmap_hugepage_range(struct vm_area_struct *vma, unsigned long start, | |||
398 | } | 398 | } |
399 | } | 399 | } |
400 | 400 | ||
401 | void unmap_hugepage_range(struct vm_area_struct *vma, unsigned long start, | ||
402 | unsigned long end) | ||
403 | { | ||
404 | /* | ||
405 | * It is undesirable to test vma->vm_file as it should be non-null | ||
406 | * for valid hugetlb area. However, vm_file will be NULL in the error | ||
407 | * cleanup path of do_mmap_pgoff. When hugetlbfs ->mmap method fails, | ||
408 | * do_mmap_pgoff() nullifies vma->vm_file before calling this function | ||
409 | * to clean up. Since no pte has actually been setup, it is safe to | ||
410 | * do nothing in this case. | ||
411 | */ | ||
412 | if (vma->vm_file) { | ||
413 | spin_lock(&vma->vm_file->f_mapping->i_mmap_lock); | ||
414 | __unmap_hugepage_range(vma, start, end); | ||
415 | spin_unlock(&vma->vm_file->f_mapping->i_mmap_lock); | ||
416 | } | ||
417 | } | ||
418 | |||
401 | static int hugetlb_cow(struct mm_struct *mm, struct vm_area_struct *vma, | 419 | static int hugetlb_cow(struct mm_struct *mm, struct vm_area_struct *vma, |
402 | unsigned long address, pte_t *ptep, pte_t pte) | 420 | unsigned long address, pte_t *ptep, pte_t pte) |
403 | { | 421 | { |