From: David Hildenbrand <david@redhat.com> mainline inclusion from mainline-v5.19-rc1 commit 500539419fae0aeb27189b2d62a238a056ca6742 category: bugfix bugzilla: 187533, https://gitee.com/openeuler/kernel/issues/I5OITX CVE: NA Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... -------------------------------- We can already theoretically fail to unmap (still having page_mapped()) in case arch_unmap_one() fails, which can happen on sparc. Failures to unmap are handled gracefully, just as if there are other references on the target page: freezing the refcount in split_huge_page_to_list() will fail if still mapped and we'll simply remap. In commit 504e070dc08f ("mm: thp: replace DEBUG_VM BUG with VM_WARN when unmap fails for split") we already converted to VM_WARN_ON_ONCE_PAGE, let's get rid of it completely now. This is a preparation for making try_to_migrate() fail on anonymous pages with GUP pins, which will make this VM_WARN_ON_ONCE_PAGE trigger more frequently. Link: https://lkml.kernel.org/r/20220428083441.37290-11-david@redhat.com Signed-off-by: David Hildenbrand <david@redhat.com> Reported-by: Yang Shi <shy828301@gmail.com> Reviewed-by: Yang Shi <shy828301@gmail.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Christoph Hellwig <hch@lst.de> Cc: David Rientjes <rientjes@google.com> Cc: Don Dutile <ddutile@redhat.com> Cc: Hugh Dickins <hughd@google.com> Cc: Jan Kara <jack@suse.cz> Cc: Jann Horn <jannh@google.com> Cc: Jason Gunthorpe <jgg@nvidia.com> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Khalid Aziz <khalid.aziz@oracle.com> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: Liang Zhang <zhangliang5@huawei.com> Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org> Cc: Michal Hocko <mhocko@kernel.org> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Mike Rapoport <rppt@linux.ibm.com> Cc: Nadav Amit <namit@vmware.com> Cc: Oded Gabbay <oded.gabbay@gmail.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Pedro Demarchi Gomes <pedrodemargomes@gmail.com> Cc: Peter Xu <peterx@redhat.com> Cc: Rik van Riel <riel@surriel.com> Cc: Roman Gushchin <guro@fb.com> Cc: Shakeel Butt <shakeelb@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Ma Wupeng <mawupeng1@huawei.com> Reviewed-by: Kefeng Wang <wangkefeng.wang@huawei.com> Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com> --- mm/huge_memory.c | 2 -- 1 file changed, 2 deletions(-) diff --git a/mm/huge_memory.c b/mm/huge_memory.c index 79c855b5adad..012ecf107ae0 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -2374,8 +2374,6 @@ static void unmap_page(struct page *page) ttu_flags |= TTU_SPLIT_FREEZE; try_to_unmap(page, ttu_flags); - - VM_WARN_ON_ONCE_PAGE(page_mapped(page), page); } static void remap_page(struct page *page, unsigned int nr) -- 2.20.1