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<-- This is a problem >> >> I'm not sure what to use, instead of that zero page! The zero page >> doesn't need to be allocated nor tracked, and so any replacement >> approaches would need either other storage, or some horrid scheme that I >> won't go so far as to write on the screen. :) > > I'm not really sure what the problem is. > > include/linux/mm.h: is_zero_pfn(page_to_pfn(page)); > > and release_pages() already contains: > if (is_huge_zero_page(page)) > continue; > > Why can't the BIO release function contain an is_zero_pfn() check? "OK." (With potential modifications as noted in the other thread with Jan Kara and Chaitanya, we'll see.) Thanks for responding with that answer so quickly, much appreciated! thanks, -- John Hubbard NVIDIA