Date:   Mon, 27 Feb 2023 09:36:12 -0800
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Subject: [PATCH v4 13/33] mm: mark VMA as being written when changing vm_flags
From:   Suren Baghdasaryan <surenb@google.com>
To:     akpm@linux-foundation.org
Cc:     michel@lespinasse.org, jglisse@google.com, mhocko@suse.com,
        vbabka@suse.cz, hannes@cmpxchg.org, mgorman@techsingularity.net,
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        songliubraving@fb.com, peterx@redhat.com, david@redhat.com,
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        soheil@google.com, leewalsh@google.com, posk@google.com,
        michalechner92@googlemail.com, linux-mm@kvack.org,
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        Suren Baghdasaryan <surenb@google.com>
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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 | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/include/linux/mm.h b/include/linux/mm.h
index bbad5d4fa81b..3d5e8666892d 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -726,28 +726,28 @@ 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_reset_once(struct vm_area_struct *vma,
 				       vm_flags_t flags)
 {
-	mmap_assert_write_locked(vma->vm_mm);
+	vma_start_write(vma);
 	WRITE_ONCE(ACCESS_PRIVATE(vma, __vm_flags), 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;
 }
 
@@ -768,7 +768,7 @@ 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);
 }
 
-- 
2.39.2.722.g9855ee24e9-goog