Re: v4.18.0+ WARNING: at mm/vmscan.c:1756 isolate_lru_page + bad page state

From: Vegard Nossum
Date: Mon Sep 10 2018 - 02:47:48 EST


On Thu, 30 Aug 2018 at 15:31, Vegard Nossum <vegard.nossum@xxxxxxxxx> wrote:
>
> Hi,
>
> Got this on a recent kernel (pretty sure it was
> 2ad0d52699700a91660a406a4046017a2d7f246a but annoyingly the oops
> itself doesn't tell me the exact version):
>
> ------------[ cut here ]------------
> trying to isolate tail page
> WARNING: CPU: 2 PID: 19156 at mm/vmscan.c:1756 isolate_lru_page+0x235/0x250

[...]

> I don't have the capacity to debug it atm and it may even have been
> fixed in mainline (though searching didn't yield any other reports
> AFAICT).
>
> I have .config and vmlinux (with DEBUG_INFO=y) if needed.
>
> It's not reproducible for the time being.

Just a quick follow-up: I have a reproducer and Kirill Shutemov has
identified the problem and provided a tentative patch.


Vegard