Date:   Fri, 27 Jan 2023 11:40:49 -0800
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Subject: [PATCH v2 12/33] mm: mark VMA as being written when changing vm_flags
From:   Suren Baghdasaryan <surenb@google.com>
To:     akpm@linux-foundation.org
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Precedence: bulk

Updates to vm_flags have to be done with VMA marked as being written for
preventing concurrent page faults or other modifications.

Signed-off-by: Suren Baghdasaryan <surenb@google.com>
---
 include/linux/mm.h | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/include/linux/mm.h b/include/linux/mm.h
index fee08e8fdce7..66dca140695e 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -720,21 +720,21 @@ static inline void vm_flags_init(struct vm_area_struct *vma,
 static inline void vm_flags_reset(struct vm_area_struct *vma,
 				  vm_flags_t flags)
 {
-	mmap_assert_write_locked(vma->vm_mm);
+	vma_start_write(vma);
 	vm_flags_init(vma, flags);
 }
 
 static inline void vm_flags_set(struct vm_area_struct *vma,
 				vm_flags_t flags)
 {
-	mmap_assert_write_locked(vma->vm_mm);
+	vma_start_write(vma);
 	ACCESS_PRIVATE(vma, __vm_flags) |= flags;
 }
 
 static inline void vm_flags_clear(struct vm_area_struct *vma,
 				  vm_flags_t flags)
 {
-	mmap_assert_write_locked(vma->vm_mm);
+	vma_start_write(vma);
 	ACCESS_PRIVATE(vma, __vm_flags) &= ~flags;
 }
 
@@ -755,7 +755,7 @@ static inline void __vm_flags_mod(struct vm_area_struct *vma,
 static inline void vm_flags_mod(struct vm_area_struct *vma,
 				vm_flags_t set, vm_flags_t clear)
 {
-	mmap_assert_write_locked(vma->vm_mm);
+	vma_start_write(vma);
 	__vm_flags_mod(vma, set, clear);
 }
 
-- 
2.39.1