Re: [PATCH v3 10/11] mm/memory_hotplug: Make unregister_memory_block_under_nodes() never fail

Michal Hocko
2019-07-01T10:27:56Z

On Mon 01-07-19 11:36:44, Oscar Salvador wrote:
> On Mon, Jul 01, 2019 at 10:51:44AM +0200, Michal Hocko wrote:
> > Yeah, we do not allow to offline multi zone (node) ranges so the current
> > code seems to be over engineered.
> >
> > Anyway, I am wondering why do we have to strictly check for already
> > removed nodes links. Is the sysfs code going to complain we we try to
> > remove again?
>
> No, sysfs will silently "fail" if the symlink has already been removed.
> At least that is what I saw last time I played with it.
>
> I guess the question is what if sysfs handling changes in the future
> and starts dropping warnings when trying to remove a symlink is not there.
> Maybe that is unlikely to happen?

And maybe we handle it then rather than have a static allocation that
everybody with hotremove configured has to pay for.
--
Michal Hocko
SUSE Labs