Messages in this thread | | | Date | Fri, 9 May 2008 15:39:10 +0900 | From | KAMEZAWA Hiroyuki <> | Subject | Re: [PATCH] memory_hotplug: always initialize pageblock bitmap. |
| |
On Fri, 9 May 2008 08:06:09 +0200 Heiko Carstens <heiko.carstens@de.ibm.com> wrote:
> From: Heiko Carstens <heiko.carstens@de.ibm.com> > > Trying to online a new memory section that was added via memory hotplug > sometimes results in crashes when the new pages are added via > __free_page. Reason for that is that the pageblock bitmap isn't > initialized and hence contains random stuff.
Hmm, curious. In my understanding, memmap_init_zone() initializes it.
__add_pages() -> __add_section() -> sparse-add_one_section() // allocate usemap -> __add_zone() -> memmap_init_zone() // reset pageblock's bitmap
Can't memmap_init_zone() does proper initialization ? ........................ Ah, ok. I see. grow_zone_span() is not called at __add_zone(), then, memmap_init_zone() doesn't initialize usemap because memmap is not in zone's range.
Recently, I added a check "zone's start_pfn < pfn < zone's end" to memmap_init_zone()'s usemap initialization for !SPARSEMEM case bug FIX. (and I think the fix itself is sane.)
How about calling grow_pgdat_span()/grow_zone_span() from __add_zone() ?
Thanks, -Kame
| |