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mm/mmap.c: don't unlock VMAs in remap_file_pages()

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Since this call uses MAP_FIXED, do_mmap() will munlock the necessary
range.  There is also an error in the loop test expression which will
evaluate as false and the loop body has never execute.

Link: https://lkml.kernel.org/r/20210223235010.2296915-1-Liam.Howlett@Oracle.com
Signed-off-by: Liam R. Howlett <Liam.Howlett@Oracle.com>
Acked-by: Hugh Dickins <hughd@google.com>
Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Liam Howlett 2021-05-04 18:38:06 -07:00 committed by Linus Torvalds
parent 575299ea18
commit fce000b1bc
1 changed files with 1 additions and 17 deletions
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18
mm/mmap.c
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@ -3029,25 +3029,9 @@ SYSCALL_DEFINE5(remap_file_pages, unsigned long, start, unsigned long, size,
flags &= MAP_NONBLOCK;
flags |= MAP_SHARED | MAP_FIXED | MAP_POPULATE;
if (vma->vm_flags & VM_LOCKED) {
struct vm_area_struct *tmp;
if (vma->vm_flags & VM_LOCKED)
flags |= MAP_LOCKED;
/* drop PG_Mlocked flag for over-mapped range */
for (tmp = vma; tmp->vm_start >= start + size;
tmp = tmp->vm_next) {
/*
* Split pmd and munlock page on the border
* of the range.
*/
vma_adjust_trans_huge(tmp, start, start + size, 0);
munlock_vma_pages_range(tmp,
max(tmp->vm_start, start),
min(tmp->vm_end, start + size));
}
}
file = get_file(vma->vm_file);
ret = do_mmap(vma->vm_file, start, size,
prot, flags, pgoff, &populate, NULL);