Re: PROBLEM: __offline_isolated_pages may offline too many pages

From: Ingo Korb
Date: Wed Dec 15 2010 - 04:27:53 EST


On 15.12.2010 01:21, KAMEZAWA Hiroyuki wrote:

It's designed for offline memory section> MAX_ORDER. pageblock_nr_pages
is tend to be smaller than that.

Do you see the problem with _exsisting_ user interface of memory hotplug ?
I think we have no control other than memory section.

The existing, exported interface (remove_memory() - the check itself is in offline_pages()) only checks if both start and end of the to-be-removed block are aligned to pageblock_nr_pages. As you noted the actual size and alignment requirements in __offline_isolated_pages can be larger that that, so I think the checks in offline_pages() should be changed (if 1<<MAX_ORDER is always >= pageblock_nr_pages) or extended (if there can be any relation between the two).

-ik
--
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/