Messages in this thread |  | | | Date | Mon, 21 Nov 2005 16:51:14 +0000 (GMT) | | From | Hugh Dickins <> | | Subject | Re: 2.6.15-rc1-mm2 -- Bad page state at free_hot_cold_page (in process 'aplay', page c18eef30) |
| |
On Mon, 21 Nov 2005, Russell King wrote: > > Does this mean that in arch/arm/mm/consistent.c, we should also set > __GFP_COMP ? Should we be doing that today?
No, I don't believe so. I notice there's use of PageReserved and page count manipulation in there, which we may well want to rationalize in a later phase, perhaps replacing by __GFP_COMP then; but I don't see any need to change what you're doing at this stage.
Looking again, to see why you even thought you might need to change: the vital thing you're doing (aside from the PageReserved, which is becoming irrelevant), which is missing from the regular high-order allocation, is the set_page_count(page, 1). That's why you don't need to change: the problems I was writing of come from when the 0-order page count goes down to 0.
Makes me wonder whether there could be a useful halfway stage to compound pages, whether it would help for the page allocator to set those counts to 1 generally.
Hugh - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
|  |