On Fri, 07 Feb 2014 16:16:04 -0500 Naoya Horiguchi <n-horigu...@ah.jp.nec.com> wrote:
> # Resending due to sending failure. Sorry if you received twice. > --- > mce-test detected a test failure when injecting error to a thp tail page. > This is because we take page refcount of the tail page in madvise_hwpoison() > while the fix in commit a3e0f9e47d5e ("mm/memory-failure.c: transfer page > count from head page to tail page after split thp") assumes that we always > take refcount on the head page. > > When a real memory error happens we take refcount on the head page where > memory_failure() is called without MF_COUNT_INCREASED set, so it seems to me > that testing memory error on thp tail page using madvise makes little sense. > > This patch cancels moving refcount in !MF_COUNT_INCREASED for valid testing. > > ... > > --- v3.14-rc1.orig/mm/memory-failure.c > +++ v3.14-rc1/mm/memory-failure.c > @@ -1042,8 +1042,10 @@ static int hwpoison_user_mappings(struct page *p, > unsigned long pfn, > * to it. Similarly, page lock is shifted. > */ > if (hpage != p) { > - put_page(hpage); > - get_page(p); > + if (!(flags && MF_COUNT_INCREASED)) { s/&&/&/ Please carefully retest this, make sure that both cases are covered? > + put_page(hpage); > + get_page(p); > + } > lock_page(p); > unlock_page(hpage); > *hpagep = p; -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/