diff options
Diffstat (limited to 'mm/mempolicy.c')
| -rw-r--r-- | mm/mempolicy.c | 29 |
1 files changed, 24 insertions, 5 deletions
diff --git a/mm/mempolicy.c b/mm/mempolicy.c index edc25195f5bd..ec2eaceffd74 100644 --- a/mm/mempolicy.c +++ b/mm/mempolicy.c @@ -384,8 +384,10 @@ void mpol_rebind_mm(struct mm_struct *mm, nodemask_t *new) VMA_ITERATOR(vmi, mm, 0); mmap_write_lock(mm); - for_each_vma(vmi, vma) + for_each_vma(vmi, vma) { + vma_start_write(vma); mpol_rebind_policy(vma->vm_policy, new); + } mmap_write_unlock(mm); } @@ -716,6 +718,14 @@ static const struct mm_walk_ops queue_pages_walk_ops = { .hugetlb_entry = queue_folios_hugetlb, .pmd_entry = queue_folios_pte_range, .test_walk = queue_pages_test_walk, + .walk_lock = PGWALK_RDLOCK, +}; + +static const struct mm_walk_ops queue_pages_lock_vma_walk_ops = { + .hugetlb_entry = queue_folios_hugetlb, + .pmd_entry = queue_folios_pte_range, + .test_walk = queue_pages_test_walk, + .walk_lock = PGWALK_WRLOCK, }; /* @@ -736,7 +746,7 @@ static const struct mm_walk_ops queue_pages_walk_ops = { static int queue_pages_range(struct mm_struct *mm, unsigned long start, unsigned long end, nodemask_t *nodes, unsigned long flags, - struct list_head *pagelist) + struct list_head *pagelist, bool lock_vma) { int err; struct queue_pages qp = { @@ -747,8 +757,10 @@ queue_pages_range(struct mm_struct *mm, unsigned long start, unsigned long end, .end = end, .first = NULL, }; + const struct mm_walk_ops *ops = lock_vma ? + &queue_pages_lock_vma_walk_ops : &queue_pages_walk_ops; - err = walk_page_range(mm, start, end, &queue_pages_walk_ops, &qp); + err = walk_page_range(mm, start, end, ops, &qp); if (!qp.first) /* whole range in hole */ @@ -768,6 +780,8 @@ static int vma_replace_policy(struct vm_area_struct *vma, struct mempolicy *old; struct mempolicy *new; + vma_assert_write_locked(vma); + pr_debug("vma %lx-%lx/%lx vm_ops %p vm_file %p set_policy %p\n", vma->vm_start, vma->vm_end, vma->vm_pgoff, vma->vm_ops, vma->vm_file, @@ -1074,7 +1088,7 @@ static int migrate_to_node(struct mm_struct *mm, int source, int dest, vma = find_vma(mm, 0); VM_BUG_ON(!(flags & (MPOL_MF_MOVE | MPOL_MF_MOVE_ALL))); queue_pages_range(mm, vma->vm_start, mm->task_size, &nmask, - flags | MPOL_MF_DISCONTIG_OK, &pagelist); + flags | MPOL_MF_DISCONTIG_OK, &pagelist, false); if (!list_empty(&pagelist)) { err = migrate_pages(&pagelist, alloc_migration_target, NULL, @@ -1313,8 +1327,12 @@ static long do_mbind(unsigned long start, unsigned long len, if (err) goto mpol_out; + /* + * Lock the VMAs before scanning for pages to migrate, to ensure we don't + * miss a concurrently inserted page. + */ ret = queue_pages_range(mm, start, end, nmask, - flags | MPOL_MF_INVERT, &pagelist); + flags | MPOL_MF_INVERT, &pagelist, true); if (ret < 0) { err = ret; @@ -1538,6 +1556,7 @@ SYSCALL_DEFINE4(set_mempolicy_home_node, unsigned long, start, unsigned long, le break; } + vma_start_write(vma); new->home_node = home_node; err = mbind_range(&vmi, vma, &prev, start, end, new); mpol_put(new); |