Commit 8d34694c1abf29df1f3c7317936b7e3e2e308d9b
Committed by
Linus Torvalds
Linus Torvalds
1 parent
1fb3f8ca0e
Exists in
smarc-l5.0.0_1.0.0-ga
and in
5 other branches
revert "mm: mempolicy: Let vma_merge and vma_split handle vma->vm_policy linkages"
Commit 05f144a0d5c2 ("mm: mempolicy: Let vma_merge and vma_split handle vma->vm_policy linkages") removed vma->vm_policy updates code but it is the purpose of mbind_range(). Now, mbind_range() is virtually a no-op and while it does not allow memory corruption it is not the right fix. This patch is a revert. [mgorman@suse.de: Edited changelog] Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: Mel Gorman <mgorman@suse.de> Cc: Christoph Lameter <cl@linux.com> Cc: Josh Boyer <jwboyer@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Showing 1 changed file with 24 additions and 17 deletions Side-by-side Diff
mm/mempolicy.c
| ... | ... | @@ -607,6 +607,27 @@ |
| 607 | 607 | return first; |
| 608 | 608 | } |
| 609 | 609 | |
| 610 | +/* Apply policy to a single VMA */ | |
| 611 | +static int policy_vma(struct vm_area_struct *vma, struct mempolicy *new) | |
| 612 | +{ | |
| 613 | + int err = 0; | |
| 614 | + struct mempolicy *old = vma->vm_policy; | |
| 615 | + | |
| 616 | + pr_debug("vma %lx-%lx/%lx vm_ops %p vm_file %p set_policy %p\n", | |
| 617 | + vma->vm_start, vma->vm_end, vma->vm_pgoff, | |
| 618 | + vma->vm_ops, vma->vm_file, | |
| 619 | + vma->vm_ops ? vma->vm_ops->set_policy : NULL); | |
| 620 | + | |
| 621 | + if (vma->vm_ops && vma->vm_ops->set_policy) | |
| 622 | + err = vma->vm_ops->set_policy(vma, new); | |
| 623 | + if (!err) { | |
| 624 | + mpol_get(new); | |
| 625 | + vma->vm_policy = new; | |
| 626 | + mpol_put(old); | |
| 627 | + } | |
| 628 | + return err; | |
| 629 | +} | |
| 630 | + | |
| 610 | 631 | /* Step 2: apply policy to a range and do splits. */ |
| 611 | 632 | static int mbind_range(struct mm_struct *mm, unsigned long start, |
| 612 | 633 | unsigned long end, struct mempolicy *new_pol) |
| ... | ... | @@ -655,23 +676,9 @@ |
| 655 | 676 | if (err) |
| 656 | 677 | goto out; |
| 657 | 678 | } |
| 658 | - | |
| 659 | - /* | |
| 660 | - * Apply policy to a single VMA. The reference counting of | |
| 661 | - * policy for vma_policy linkages has already been handled by | |
| 662 | - * vma_merge and split_vma as necessary. If this is a shared | |
| 663 | - * policy then ->set_policy will increment the reference count | |
| 664 | - * for an sp node. | |
| 665 | - */ | |
| 666 | - pr_debug("vma %lx-%lx/%lx vm_ops %p vm_file %p set_policy %p\n", | |
| 667 | - vma->vm_start, vma->vm_end, vma->vm_pgoff, | |
| 668 | - vma->vm_ops, vma->vm_file, | |
| 669 | - vma->vm_ops ? vma->vm_ops->set_policy : NULL); | |
| 670 | - if (vma->vm_ops && vma->vm_ops->set_policy) { | |
| 671 | - err = vma->vm_ops->set_policy(vma, new_pol); | |
| 672 | - if (err) | |
| 673 | - goto out; | |
| 674 | - } | |
| 679 | + err = policy_vma(vma, new_pol); | |
| 680 | + if (err) | |
| 681 | + goto out; | |
| 675 | 682 | } |
| 676 | 683 | |
| 677 | 684 | out: |