On 04/02/2016 05:37 PM, Konstantin Khlebnikov wrote:
Khugepaged detects own VMAs by checking vm_file and vm_ops but this
way it cannot distinguish private /dev/zero mappings from other special
mappings like /dev/hpet which has no vm_ops and popultes PTEs in mmap.
This fixes false-positive VM_BUG_ON and prevents installing THP where
they are not expected.
Signed-off-by: Konstantin Khlebnikov <koc...@gmail.com>
Reported-by: Dmitry Vyukov <dvyu...@google.com>
Link:
http://lkml.kernel.org/r/cact4y+zmuzmv5cjsfoexviwqdabagt7t+stkftqan9ydtge...@mail.gmail.com
Fixes: 78f11a255749 ("mm: thp: fix /dev/zero MAP_PRIVATE and vm_flags cleanups")
Cc: stable <sta...@vger.kernel.org>
Acked-by: Vlastimil Babka <vba...@suse.cz>
