hugetlb: pass head page to remove_hugetlb_page()
authorNaoya Horiguchi <naoya.horiguchi@nec.com>
Sat, 5 Jun 2021 03:01:27 +0000 (20:01 -0700)
committerLinus Torvalds <torvalds@linux-foundation.org>
Sat, 5 Jun 2021 15:58:11 +0000 (08:58 -0700)
When memory_failure() or soft_offline_page() is called on a tail page of
some hugetlb page, "BUG: unable to handle page fault" error can be
triggered.

remove_hugetlb_page() dereferences page->lru, so it's assumed that the
page points to a head page, but one of the caller,
dissolve_free_huge_page(), provides remove_hugetlb_page() with 'page'
which could be a tail page.  So pass 'head' to it, instead.

Link: https://lkml.kernel.org/r/20210526235257.2769473-1-nao.horiguchi@gmail.com
Fixes: 6eb4e88a6d27 ("hugetlb: create remove_hugetlb_page() to separate functionality")
Signed-off-by: Naoya Horiguchi <naoya.horiguchi@nec.com>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Reviewed-by: Muchun Song <songmuchun@bytedance.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Oscar Salvador <osalvador@suse.de>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
mm/hugetlb.c

index 95918f4..470f7b5 100644 (file)
@@ -1793,7 +1793,7 @@ retry:
                        SetPageHWPoison(page);
                        ClearPageHWPoison(head);
                }
-               remove_hugetlb_page(h, page, false);
+               remove_hugetlb_page(h, head, false);
                h->max_huge_pages--;
                spin_unlock_irq(&hugetlb_lock);
                update_and_free_page(h, head);