Message ID | 20210819001958.2365157-1-naoya.horiguchi@linux.dev (mailing list archive) |
---|---|
State | New |
Headers | show |
Series | [v2] mm/hwpoison: Retry with shake_page() for unhandlable pages | expand |
On Wed, Aug 18, 2021 at 5:20 PM Naoya Horiguchi <naoya.horiguchi@linux.dev> wrote: > > From: Naoya Horiguchi <naoya.horiguchi@nec.com> > > HWPoisonHandlable() sometimes returns false for typical user pages > due to races with average memory events like transfers over LRU lists. > This causes failures in hwpoison handling. > > There's retry code for such a case but does not work because the retry > loop reaches the retry limit too quickly before the page settles down to > handlable state. Let get_any_page() call shake_page() to fix it. > > Fixes: 25182f05ffed ("mm,hwpoison: fix race with hugetlb page allocation") > Reported-by: Tony Luck <tony.luck@intel.com> > Signed-off-by: Naoya Horiguchi <naoya.horiguchi@nec.com> > Cc: stable@vger.kernel.org # 5.13 > --- > ChangeLog v2: > - get_any_page() return -EIO when retry limit reached (by Yang Shi) Thanks for taking this. The fix looks good to me. Reviewed-by: Yang Shi <shy828301@gmail.com> > --- > mm/memory-failure.c | 12 +++++++++--- > 1 file changed, 9 insertions(+), 3 deletions(-) > > diff --git v5.14-rc6/mm/memory-failure.c v5.14-rc6_patched/mm/memory-failure.c > index eefd823deb67..470400cc7513 100644 > --- v5.14-rc6/mm/memory-failure.c > +++ v5.14-rc6_patched/mm/memory-failure.c > @@ -1146,7 +1146,7 @@ static int __get_hwpoison_page(struct page *page) > * unexpected races caused by taking a page refcount. > */ > if (!HWPoisonHandlable(head)) > - return 0; > + return -EBUSY; > > if (PageTransHuge(head)) { > /* > @@ -1199,9 +1199,15 @@ static int get_any_page(struct page *p, unsigned long flags) > } > goto out; > } else if (ret == -EBUSY) { > - /* We raced with freeing huge page to buddy, retry. */ > - if (pass++ < 3) > + /* > + * We raced with (possibly temporary) unhandlable > + * page, retry. > + */ > + if (pass++ < 3) { > + shake_page(p, 1); > goto try_again; > + } > + ret = -EIO; > goto out; > } > } > -- > 2.25.1 > >
diff --git v5.14-rc6/mm/memory-failure.c v5.14-rc6_patched/mm/memory-failure.c index eefd823deb67..470400cc7513 100644 --- v5.14-rc6/mm/memory-failure.c +++ v5.14-rc6_patched/mm/memory-failure.c @@ -1146,7 +1146,7 @@ static int __get_hwpoison_page(struct page *page) * unexpected races caused by taking a page refcount. */ if (!HWPoisonHandlable(head)) - return 0; + return -EBUSY; if (PageTransHuge(head)) { /* @@ -1199,9 +1199,15 @@ static int get_any_page(struct page *p, unsigned long flags) } goto out; } else if (ret == -EBUSY) { - /* We raced with freeing huge page to buddy, retry. */ - if (pass++ < 3) + /* + * We raced with (possibly temporary) unhandlable + * page, retry. + */ + if (pass++ < 3) { + shake_page(p, 1); goto try_again; + } + ret = -EIO; goto out; } }