[RFC PATCH RESEND 09/28] mm/mempolicy: mark VMA as locked when changing protection policy
From: Suren Baghdasaryan <surenb@google.com>
Date: 2022-09-01 17:36:56
Also in:
linux-arm-kernel, linux-mm, lkml
Subsystem:
memory management, memory management - memory policy and migration, the rest · Maintainers:
Andrew Morton, David Hildenbrand, Linus Torvalds
Protect VMA from concurrent page fault handler while performing VMA protection policy changes. Signed-off-by: Suren Baghdasaryan <surenb@google.com> --- mm/mempolicy.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-)
diff --git a/mm/mempolicy.c b/mm/mempolicy.c
index b73d3248d976..6be1e5c75556 100644
--- a/mm/mempolicy.c
+++ b/mm/mempolicy.c@@ -383,8 +383,10 @@ void mpol_rebind_mm(struct mm_struct *mm, nodemask_t *new) struct vm_area_struct *vma; mmap_write_lock(mm); - for (vma = mm->mmap; vma; vma = vma->vm_next) + for (vma = mm->mmap; vma; vma = vma->vm_next) { + vma_mark_locked(vma); mpol_rebind_policy(vma->vm_policy, new); + } mmap_write_unlock(mm); }
@@ -632,6 +634,7 @@ unsigned long change_prot_numa(struct vm_area_struct *vma, struct mmu_gather tlb; int nr_updated; + vma_mark_locked(vma); tlb_gather_mmu(&tlb, vma->vm_mm); nr_updated = change_protection(&tlb, vma, addr, end, PAGE_NONE,
@@ -765,6 +768,7 @@ static int vma_replace_policy(struct vm_area_struct *vma, if (IS_ERR(new)) return PTR_ERR(new); + vma_mark_locked(vma); if (vma->vm_ops && vma->vm_ops->set_policy) { err = vma->vm_ops->set_policy(vma, new); if (err)
--
2.37.2.789.g6183377224-goog