Re: [PATCH] memory_hotplug: cond_resched in __remove_pages

From: Michal Hocko
Date: Wed Oct 31 2018 - 17:42:13 EST


On Wed 31-10-18 12:15:50, Andrew Morton wrote:
> On Wed, 31 Oct 2018 13:58:40 +0100 Michal Hocko <mhocko@xxxxxxxxxx> wrote:
>
> > From: Michal Hocko <mhocko@xxxxxxxx>
> >
> > We have received a bug report that unbinding a large pmem (>1TB)
> > can result in a soft lockup:
> >
> > ...
> >
> > It has been reported on an older (4.12) kernel but the current upstream
> > code doesn't cond_resched in the hot remove code at all and the given
> > range to remove might be really large. Fix the issue by calling cond_resched
> > once per memory section.
> >
>
> Worthy of a cc:stable, I suggest?

It is simple enough and we will surely have it in 4.12 based SLES
kernels. So I do not really mind cc: stable.

--
Michal Hocko
SUSE Labs