Re: [PATCH] mm,memory_hotplug: Fix scan_movable_pages for gigantic hugepages

From: Oscar Salvador
Date: Wed Jan 23 2019 - 05:18:53 EST


On Wed, Jan 23, 2019 at 10:47:17AM +0100, Michal Hocko wrote:
> So this should be probably folded into the above patch as it is
> incomplete unless I am missing something.

Well, they are triggered from different paths.
The former error was triggered in:

removable_show
is_mem_section_removable
is_pageblock_removable_nolock
has_unmovable_pages

while this one is triggered when actually doing the offline operation

__offline_pages
scan_movable_pages

But I do agree that one without the other is not really useful, an incomplete.
The truth is that I did not spot this one when fixing [1] because I did not
really try to offline the memblock back then, so my fault.

While I agree that the best approach would be to fold this one into [1],
I am not sure if it is too late for that as it seems that [1] was already
released into mainline, and moreover to stable.

I guess I will have Andrew decide what is the best way to carry on here.

[1] https://patchwork.kernel.org/patch/10739963/

>
> > Signed-off-by: Oscar Salvador <osalvador@xxxxxxx>
>
> Other than that the change looks good to me.
>
> Acked-by: Michal Hocko <mhocko@xxxxxxxx>

Thanks!
--
Oscar Salvador
SUSE L3