Messages in this thread | | | Date | Mon, 01 Apr 2013 10:01:49 +0900 | From | Kamezawa Hiroyuki <> | Subject | Re: [PATCH] THP: Use explicit memory barrier |
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(2013/04/01 8:45), Minchan Kim wrote: > __do_huge_pmd_anonymous_page depends on page_add_new_anon_rmap's > spinlock for making sure that clear_huge_page write become visible > after set set_pmd_at() write. > > But lru_cache_add_lru uses pagevec so it could miss spinlock > easily so above rule was broken so user may see inconsistent data. > This patch fixes it with using explict barrier rather than depending > on lru spinlock. >
Hmm...how about do_anonymous_page() ? there are no comments/locks/barriers. Users can see non-zero value after page fault in theory ?
Thanks, -Kame
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