Commit ff69fb81 authored by Liam Howlett's avatar Liam Howlett Committed by Linus Torvalds
Browse files

mm/ksm: use vma_lookup() in find_mergeable_vma() 

Use vma_lookup() to find the VMA at a specific address.  As vma_lookup()
will return NULL if the address is not within any VMA, the start address
no longer needs to be validated.

Link: https://lkml.kernel.org/r/20210521174745.2219620-19-Liam.Howlett@Oracle.com


Signed-off-by: default avatarLiam R. Howlett <Liam.Howlett@Oracle.com>
Reviewed-by: default avatarLaurent Dufour <ldufour@linux.ibm.com>
Acked-by: default avatarDavid Hildenbrand <david@redhat.com>
Acked-by: default avatarDavidlohr Bueso <dbueso@suse.de>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 46e6b31d

mm/ksm.c

+2 −4
Original line number Diff line number Diff line
@@ -521,10 +521,8 @@ static struct vm_area_struct *find_mergeable_vma(struct mm_struct *mm, 
	struct vm_area_struct *vma;

	if (ksm_test_exit(mm))

		return NULL;

	vma = find_vma(mm, addr);

	if (!vma || vma->vm_start > addr)

		return NULL;

	if (!(vma->vm_flags & VM_MERGEABLE) || !vma->anon_vma)

	vma = vma_lookup(mm, addr);

	if (!vma || !(vma->vm_flags & VM_MERGEABLE) || !vma->anon_vma)

		return NULL;

	return vma;

}