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Date:   Mon,  9 Jan 2023 12:53:12 -0800
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Subject: [PATCH 17/41] mm/mmap: move VMA locking before anon_vma_lock_write call
From:   Suren Baghdasaryan <surenb@google.com>
To:     akpm@linux-foundation.org
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Precedence: bulk

Move VMA flag modification (which now implies VMA locking) before
anon_vma_lock_write to match the locking order of page fault handler.

Signed-off-by: Suren Baghdasaryan <surenb@google.com>
---
 mm/mmap.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/mm/mmap.c b/mm/mmap.c
index fa994ae903d9..53d885e70a54 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -2953,13 +2953,13 @@ static int do_brk_flags(struct ma_state *mas, struct vm_area_struct *vma,
 		if (mas_preallocate(mas, vma, GFP_KERNEL))
 			goto unacct_fail;
 
+		set_vm_flags(vma, VM_SOFTDIRTY);
 		vma_adjust_trans_huge(vma, vma->vm_start, addr + len, 0);
 		if (vma->anon_vma) {
 			anon_vma_lock_write(vma->anon_vma);
 			anon_vma_interval_tree_pre_update_vma(vma);
 		}
 		vma->vm_end = addr + len;
-		set_vm_flags(vma, VM_SOFTDIRTY);
 		mas_store_prealloc(mas, vma);
 
 		if (vma->anon_vma) {
-- 
2.39.0