From: Hugh Dickins <hughd@xxxxxxxxxx> Subject: mm: _install_special_mapping() apply VM_LOCKED_CLEAR_MASK _install_special_mapping() adds the VM_SPECIAL bit VM_DONTEXPAND (and never attempts to update locked_vm), so it ought to be consistent with mmap_region() and mlock_fixup(), making sure not to add VM_LOCKED or VM_LOCKONFAULT. I doubt that this fixes any problem in practice: just do it for consistency. Link: https://lkml.kernel.org/r/a85315a9-21d1-6133-c5fc-c89863dfb25b@xxxxxxxxxx Signed-off-by: Hugh Dickins <hughd@xxxxxxxxxx> Cc: Vlastimil Babka <vbabka@xxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/mmap.c | 1 + 1 file changed, 1 insertion(+) --- a/mm/mmap.c~mm-_install_special_mapping-apply-vm_locked_clear_mask +++ a/mm/mmap.c @@ -3448,6 +3448,7 @@ static struct vm_area_struct *__install_ vma->vm_end = addr + len; vma->vm_flags = vm_flags | mm->def_flags | VM_DONTEXPAND | VM_SOFTDIRTY; + vma->vm_flags &= VM_LOCKED_CLEAR_MASK; vma->vm_page_prot = vm_get_page_prot(vma->vm_flags); vma->vm_ops = ops; _
