On Tue, May 14, 2024 at 3:14 PM Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> wrote: > > On Sat, 11 May 2024 11:54:35 +0800 Miaohe Lin <linmiaohe@xxxxxxxxxx> wrote: > > > When I did memory failure tests recently, below panic occurs: > > > > kernel BUG at include/linux/mm.h:1135! > > invalid opcode: 0000 [#1] PREEMPT SMP NOPTI > > CPU: 9 PID: 137 Comm: kswapd1 Not tainted 6.9.0-rc4-00491-gd5ce28f156fe-dirty #14 > > > > ... > > > > --- a/mm/huge_memory.c > > +++ b/mm/huge_memory.c > > @@ -208,6 +208,7 @@ static bool get_huge_zero_page(void) > > __free_pages(zero_page, compound_order(zero_page)); > > goto retry; > > } > > + __SetPageReserved(zero_page); > > WRITE_ONCE(huge_zero_pfn, page_to_pfn(zero_page)); > > > > /* We take additional reference here. It will be put back by shrinker */ > > @@ -260,6 +261,7 @@ static unsigned long shrink_huge_zero_page_scan(struct shrinker *shrink, > > struct page *zero_page = xchg(&huge_zero_page, NULL); > > BUG_ON(zero_page == NULL); > > WRITE_ONCE(huge_zero_pfn, ~0UL); > > + __ClearPageReserved(zero_page); > > __free_pages(zero_page, compound_order(zero_page)); > > return HPAGE_PMD_NR; > > } > > This causes a bit of a mess when staged ahead of mm-stable. So to > avoid disruption I staged it behind mm-stable. This means that when > the -stable maintainers try to merge it, they will ask for a fixed up > version for older kernels so you can please just send them this > version. Can you please drop this from mm-unstable since both I and David nack'ed a similar patch in another thread. https://lore.kernel.org/linux-mm/20240511032801.1295023-1-linmiaohe@xxxxxxxxxx/ Both patches actually do the same thing, just this one uses page, the other one uses folio. > > To facilitate this I added the below adjustment: > > (btw, shouldn't get_huge_zero_page() and shrink_huge_zero_page_scan() > be renamed to *_folio_*?) > > > From: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> > Subject: mm-huge_memory-mark-huge_zero_page-reserved-fix > Date: Tue May 14 01:53:37 PM PDT 2024 > > Update it for 5691753d73a2 ("mm: convert huge_zero_page to huge_zero_folio") > > Cc: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx> > Cc: David Hildenbrand <david@xxxxxxxxxx> > Cc: Miaohe Lin <linmiaohe@xxxxxxxxxx> > Cc: Naoya Horiguchi <nao.horiguchi@xxxxxxxxx> > Cc: Xu Yu <xuyu@xxxxxxxxxxxxxxxxx> > Cc: Yang Shi <shy828301@xxxxxxxxx> > Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> > --- > > mm/huge_memory.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > --- a/mm/huge_memory.c~mm-huge_memory-mark-huge_zero_page-reserved-fix > +++ a/mm/huge_memory.c > @@ -212,7 +212,7 @@ retry: > folio_put(zero_folio); > goto retry; > } > - __SetPageReserved(zero_page); > + __folio_set_reserved(zero_folio); > WRITE_ONCE(huge_zero_pfn, folio_pfn(zero_folio)); > > /* We take additional reference here. It will be put back by shrinker */ > @@ -265,7 +265,7 @@ static unsigned long shrink_huge_zero_pa > struct folio *zero_folio = xchg(&huge_zero_folio, NULL); > BUG_ON(zero_folio == NULL); > WRITE_ONCE(huge_zero_pfn, ~0UL); > - __ClearPageReserved(zero_page); > + __folio_clear_reserved(zero_folio); > folio_put(zero_folio); > return HPAGE_PMD_NR; > } > _ >
