BUG: non-zero pgtables_bytes on freeing mm: ADDR

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: 5168afe6 Merge tag 'for-linus-20190726-2' of git://git.ker..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=13c333f0600000
kernel config: https://syzkaller.appspot.com/x/.config?x=4809ada7c73f0407
dashboard link: https://syzkaller.appspot.com/bug?extid=af34e5dc81524a984b64
compiler: gcc (GCC) 9.0.0 20181231 (experimental)

Unfortunately, I don't have any reproducer for this crash yet.

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+af34e5...@syzkaller.appspotmail.com

BUG: non-zero pgtables_bytes on freeing mm: 139264


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[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.