From patchwork Fri Feb 5 02:32:13 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrew Morton X-Patchwork-Id: 378097 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-15.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 282EAC433E0 for ; Fri, 5 Feb 2021 02:33:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D1DA264FB9 for ; Fri, 5 Feb 2021 02:33:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230226AbhBECdH (ORCPT ); Thu, 4 Feb 2021 21:33:07 -0500 Received: from mail.kernel.org ([198.145.29.99]:45596 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230218AbhBECcz (ORCPT ); Thu, 4 Feb 2021 21:32:55 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id 46F1664FB9; Fri, 5 Feb 2021 02:32:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1612492334; bh=5dF3wYRxUT7z1CH7ZhqlJ7Ak7R/4Qo16/DGhNKCIElE=; h=Date:From:To:Subject:In-Reply-To:From; b=lLzbEgtg/oBqWX+rtAt1bKwpwPd1BaorLa/tqn5G2J5Wd1tCDGaa3ioXhknlId2gU J9S8hzuI0/dqpdn/5dyEpFtnRE7/+rHbD08OWN95zvHkR3GKQqR1e0tEDbvJ3tHMHM sSWeGQLJr/R1Ylijv7Q5PWkI25VBjxL9ha/hUomE= Date: Thu, 04 Feb 2021 18:32:13 -0800 From: Andrew Morton To: akpm@linux-foundation.org, david@redhat.com, linux-mm@kvack.org, mhocko@suse.com, mike.kravetz@oracle.com, mm-commits@vger.kernel.org, osalvador@suse.de, shy828301@gmail.com, songmuchun@bytedance.com, stable@vger.kernel.org, torvalds@linux-foundation.org Subject: [patch 04/18] mm: hugetlb: remove VM_BUG_ON_PAGE from page_huge_active Message-ID: <20210205023213._BtpJL1s-%akpm@linux-foundation.org> In-Reply-To: <20210204183135.e123f0d6027529f2cf500cf2@linux-foundation.org> User-Agent: s-nail v14.8.16 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Muchun Song Subject: mm: hugetlb: remove VM_BUG_ON_PAGE from page_huge_active The page_huge_active() can be called from scan_movable_pages() which do not hold a reference count to the HugeTLB page. So when we call page_huge_active() from scan_movable_pages(), the HugeTLB page can be freed parallel. Then we will trigger a BUG_ON which is in the page_huge_active() when CONFIG_DEBUG_VM is enabled. Just remove the VM_BUG_ON_PAGE. Link: https://lkml.kernel.org/r/20210115124942.46403-6-songmuchun@bytedance.com Fixes: 7e1f049efb86 ("mm: hugetlb: cleanup using paeg_huge_active()") Signed-off-by: Muchun Song Reviewed-by: Mike Kravetz Acked-by: Michal Hocko Reviewed-by: Oscar Salvador Cc: David Hildenbrand Cc: Yang Shi Cc: Signed-off-by: Andrew Morton --- mm/hugetlb.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) --- a/mm/hugetlb.c~mm-hugetlb-remove-vm_bug_on_page-from-page_huge_active +++ a/mm/hugetlb.c @@ -1361,8 +1361,7 @@ struct hstate *size_to_hstate(unsigned l */ bool page_huge_active(struct page *page) { - VM_BUG_ON_PAGE(!PageHuge(page), page); - return PageHead(page) && PagePrivate(&page[1]); + return PageHeadHuge(page) && PagePrivate(&page[1]); } /* never called for tail page */