Messages in this thread Patch in this message | | | From | David Hildenbrand <> | Subject | [PATCH v3 10/16] mm/huge_memory: remove outdated VM_WARN_ON_ONCE_PAGE from unmap_page() | Date | Tue, 29 Mar 2022 18:04:34 +0200 |
| |
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.
Reported-by: Yang Shi <shy828301@gmail.com> Reviewed-by: Yang Shi <shy828301@gmail.com> Signed-off-by: David Hildenbrand <david@redhat.com> --- mm/huge_memory.c | 2 -- 1 file changed, 2 deletions(-)
diff --git a/mm/huge_memory.c b/mm/huge_memory.c index dd16819c5edc..70298431e128 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -2241,8 +2241,6 @@ static void unmap_page(struct page *page) try_to_migrate(folio, ttu_flags); else try_to_unmap(folio, ttu_flags | TTU_IGNORE_MLOCK); - - VM_WARN_ON_ONCE_PAGE(page_mapped(page), page); } static void remap_page(struct folio *folio, unsigned long nr) -- 2.35.1
| |