Problem:
/sys/devices/system/memory/memoryX/removable file shows whether the section
can be offlined or not. Returns "1" if it seems removable.
Now, the file uses a similar logic to one offline_pages() uses.
Problem here is.
- removable detection logics of is_removable() and offline_pages() is
different from each other.
- The logic, which check MIGRATE_TYPE, tend to be incorrect once fragmented.
MIGRATE_TYPE of a pageblock is just a hint, no guarantee.
Then, this patch set does.
- use the same logic between is_removable() and offline_pages().
- don't use MIGRATE_TYPE, check the memmap itself directly rather than hint.
Brief patch description:
1. bugfix for is_removable() check. I think this should be back ported.
2. bugfix for callback at counting immobile pages.
I think the old logic rarely hits this bug..so, not necessary to backport.
3. the unified new logic for is_remobable.
Only patch1 is CCed to stable for now and the patch series itself is onto
mmotm-08-27.
Thanks,
-Kame
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@xxxxxxxxxx For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>