BUG: Bad rss-counter state

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: d6943e63 ANDROID: GKI: x86: Drop CONFIG_DEVPORT
git tree: android-5.4
console output: https://syzkaller.appspot.com/x/log.txt?x=17335d32100000
kernel config: https://syzkaller.appspot.com/x/.config?x=d45cd2456c11ed8a
dashboard link: https://syzkaller.appspot.com/bug?extid=2b91f36e96d47a31a670
compiler: Android (6032204 based on r370808) clang version 10.0.1 (https://android.googlesource.com/toolchain/llvm-project 6e765c10313d15c02ab29977a82938f66742c3a9)
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=120c35ec100000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=124aab14100000

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+2b91f3...@syzkaller.appspotmail.com

BUG: Bad rss-counter state mm:0000000064b66b9a type:MM_ANONPAGES val:1


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