[PATCH v3 14/35] mm/mmap: move VMA locking before vma_adjust_trans_huge call
From: Suren Baghdasaryan <surenb@google.com>
Date: 2023-02-16 05:19:42
Also in:
linux-mm, lkml
Subsystem:
memory management, memory mapping, the rest · Maintainers:
Andrew Morton, Liam R. Howlett, Lorenzo Stoakes, Linus Torvalds
vma_adjust_trans_huge() modifies the VMA and such modifications should be done after VMA is marked as being written. Therefore move VMA flag modifications before vma_adjust_trans_huge() so that VMA is marked before all these modifications. Signed-off-by: Suren Baghdasaryan <surenb@google.com> --- mm/mmap.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/mm/mmap.c b/mm/mmap.c
index 06c0f6686de8..c5f2ddf17b87 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c@@ -2910,11 +2910,12 @@ static int do_brk_flags(struct vma_iterator *vmi, struct vm_area_struct *vma, if (vma_iter_prealloc(vmi)) goto unacct_fail; + /* Set flags first to implicitly lock the VMA before updates */ + vm_flags_set(vma, VM_SOFTDIRTY); vma_adjust_trans_huge(vma, vma->vm_start, addr + len, 0); init_vma_prep(&vp, vma); vma_prepare(&vp); vma->vm_end = addr + len; - vm_flags_set(vma, VM_SOFTDIRTY); vma_iter_store(vmi, vma); vma_complete(&vp, vmi, mm);
--
2.39.1