BUG: non-zero pgtables_bytes on freeing mm: NUM

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: c1a6d08348fc Add linux-next specific files for 20210715
git tree: linux-next
console output: https://syzkaller.appspot.com/x/log.txt?x=1680525a300000
kernel config: https://syzkaller.appspot.com/x/.config?x=5ef73f190e4b0b9a
dashboard link: https://syzkaller.appspot.com/bug?extid=5e693f0228adf197a0fa
CC: [linux-...@vger.kernel.org]

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

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+5e693f...@syzkaller.appspotmail.com

BUG: non-zero pgtables_bytes on freeing mm: 28672


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[syzbot]

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