Commit c7322933 authored by Suren Baghdasaryan's avatar Suren Baghdasaryan Committed by Andrew Morton
Browse files

mm: mark VMA as being written when changing vm_flags 

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

Link: https://lkml.kernel.org/r/20230227173632.3292573-14-surenb@google.com


Signed-off-by: default avatarSuren Baghdasaryan <surenb@google.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
parent 5e31275c

include/linux/mm.h

+5 −5
Original line number Diff line number Diff line
@@ -727,28 +727,28 @@ 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;

}
@@ -769,7 +769,7 @@ 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);

}