Mark the VMA touched when policy changes are applied to it so that speculative page fault will be aborted.
Signed-off-by: Laurent Dufour <[email protected]> --- mm/mempolicy.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/mm/mempolicy.c b/mm/mempolicy.c index 13d32c25226c..5e44b3e69a0d 100644 --- a/mm/mempolicy.c +++ b/mm/mempolicy.c @@ -447,8 +447,11 @@ void mpol_rebind_mm(struct mm_struct *mm, nodemask_t *new) struct vm_area_struct *vma; down_write(&mm->mmap_sem); - for (vma = mm->mmap; vma; vma = vma->vm_next) + for (vma = mm->mmap; vma; vma = vma->vm_next) { + write_seqcount_begin(&vma->vm_sequence); mpol_rebind_policy(vma->vm_policy, new, MPOL_REBIND_ONCE); + write_seqcount_end(&vma->vm_sequence); + } up_write(&mm->mmap_sem); } @@ -711,6 +714,7 @@ static int vma_replace_policy(struct vm_area_struct *vma, if (IS_ERR(new)) return PTR_ERR(new); + write_seqcount_begin(&vma->vm_sequence); if (vma->vm_ops && vma->vm_ops->set_policy) { err = vma->vm_ops->set_policy(vma, new); if (err) @@ -719,10 +723,12 @@ static int vma_replace_policy(struct vm_area_struct *vma, old = vma->vm_policy; vma->vm_policy = new; /* protected by mmap_sem */ + write_seqcount_end(&vma->vm_sequence); mpol_put(old); return 0; err_out: + write_seqcount_end(&vma->vm_sequence); mpol_put(new); return err; } -- 2.7.4
