Re: [PATCH 1/2 V2] memory-hotplug: fix BUG_ON in move_freepages()

From: Yasuaki Ishimatsu
Date: Sun Apr 19 2015 - 22:11:23 EST



> When hot adding memory and creating new node, the node is offline.
> And after calling node_set_online(), the node becomes online.
>
> Oh, sorry. I misread your ptaches.
>

Please ignore it...

Thanks,
Yasuaki Ishimatsu

On
Yasuaki Ishimatsu <yasu.isimatu@xxxxxxxxx> wrote:

>
> When hot adding memory and creating new node, the node is offline.
> And after calling node_set_online(), the node becomes online.
>
> Oh, sorry. I misread your ptaches.
>
> Thanks,
> Yasuaki Ishimatsu
>
> On Mon, 20 Apr 2015 09:33:10 +0800
> Xishi Qiu <qiuxishi@xxxxxxxxxx> wrote:
>
> > On 2015/4/18 4:05, Yasuaki Ishimatsu wrote:
> >
> > >
> > > Your patches will fix your issue.
> > > But, if BIOS reports memory first at node hot add, pgdat can
> > > not be initialized.
> > >
> > > Memory hot add flows are as follows:
> > >
> > > add_memory
> > > ...
> > > -> hotadd_new_pgdat()
> > > ...
> > > -> node_set_online(nid)
> > >
> > > When calling hotadd_new_pgdat() for a hot added node, the node is
> > > offline because node_set_online() is not called yet. So if applying
> > > your patches, the pgdat is not initialized in this case.
> > >
> > > Thanks,
> > > Yasuaki Ishimatsu
> > >
> >
> > Hi Yasuaki,
> >
> > I'm not quite understand, when BIOS reports memory first, why pgdat
> > can not be initialized?
> > When hotadd a new node, hotadd_new_pgdat() will be called too, and
> > when hotadd memory to a existent node, it's no need to call hotadd_new_pgdat(),
> > right?
> >
> > Thanks,
> > Xishi Qiu
> >
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/