From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1F7A2C25B0E for ; Fri, 19 Aug 2022 06:59:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1346888AbiHSG7O (ORCPT ); Fri, 19 Aug 2022 02:59:14 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49158 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1346855AbiHSG7C (ORCPT ); Fri, 19 Aug 2022 02:59:02 -0400 Received: from szxga02-in.huawei.com (szxga02-in.huawei.com [45.249.212.188]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 12AF11F2EB for ; Thu, 18 Aug 2022 23:58:57 -0700 (PDT) Received: from dggpemm500024.china.huawei.com (unknown [172.30.72.54]) by szxga02-in.huawei.com (SkyGuard) with ESMTP id 4M8CDK6D5pzXdtL; Fri, 19 Aug 2022 14:54:41 +0800 (CST) Received: from dggpemm100009.china.huawei.com (7.185.36.113) by dggpemm500024.china.huawei.com (7.185.36.203) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.24; Fri, 19 Aug 2022 14:58:54 +0800 Received: from [10.174.179.24] (10.174.179.24) by dggpemm100009.china.huawei.com (7.185.36.113) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.24; Fri, 19 Aug 2022 14:58:53 +0800 Subject: Re: [PATCH -next] bootmem: remove the vmemmap pages from kmemleak in free_bootmem_page To: Muchun Song References: <20220818132104.2144770-1-liushixin2@huawei.com> <8EC06FE1-3963-4F22-83DF-48B3EFAA62CA@linux.dev> CC: Muchun Song , Matthew Wilcox , Mike Kravetz , Oscar Salvador , Andrew Morton , , Linux MM From: Liu Shixin Message-ID: <688c930c-57aa-800b-57a5-fe7c8aacdbda@huawei.com> Date: Fri, 19 Aug 2022 14:58:53 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:45.0) Gecko/20100101 Thunderbird/45.7.1 MIME-Version: 1.0 In-Reply-To: <8EC06FE1-3963-4F22-83DF-48B3EFAA62CA@linux.dev> Content-Type: text/plain; charset="windows-1252" Content-Transfer-Encoding: 7bit X-Originating-IP: [10.174.179.24] X-ClientProxiedBy: dggems701-chm.china.huawei.com (10.3.19.178) To dggpemm100009.china.huawei.com (7.185.36.113) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2022/8/19 11:31, Muchun Song wrote: > >> On Aug 18, 2022, at 21:21, Liu Shixin wrote: >> >> The vmemmap pages is marked by kmemleak when allocated from memblock. >> Remove it from kmemleak when free the page. Otherwise, when we reuse the >> page, kmemleak may report such an error and then stop working. >> >> kmemleak: Cannot insert 0xffff98fb6eab3d40 into the object search tree (overlaps existing) >> kmemleak: Kernel memory leak detector disabled >> kmemleak: Object 0xffff98fb6be00000 (size 335544320): >> kmemleak: comm "swapper", pid 0, jiffies 4294892296 >> kmemleak: min_count = 0 >> kmemleak: count = 0 >> kmemleak: flags = 0x1 >> kmemleak: checksum = 0 >> kmemleak: backtrace: >> >> Fixes: f41f2ed43ca5 ("mm: hugetlb: free the vmemmap pages associated with each HugeTLB page") >> Signed-off-by: Liu Shixin >> --- >> include/linux/bootmem_info.h | 6 ++++-- >> 1 file changed, 4 insertions(+), 2 deletions(-) >> >> diff --git a/include/linux/bootmem_info.h b/include/linux/bootmem_info.h >> index cc35d010fa94..899bc56948f7 100644 >> --- a/include/linux/bootmem_info.h >> +++ b/include/linux/bootmem_info.h >> @@ -3,6 +3,7 @@ >> #define __LINUX_BOOTMEM_INFO_H >> >> #include >> +#include >> >> /* >> * Types for free bootmem stored in page->lru.next. These have to be in >> @@ -38,9 +39,10 @@ static inline void free_bootmem_page(struct page *page) >> */ >> VM_BUG_ON_PAGE(page_ref_count(page) != 2, page); > I am wondering if we should fix put_page_bootmem() instead of > free_bootmem_page() since there are some users of put_page_bootmem() > to free a page allocated from memblock which also can be reused > afterwards. > > Thanks. Thanks for your advise, it looks like that this problem may be occurs in memory hotremove too. So it's more appropriate to fix put_page_bootmem() Thanks, > >> - if (magic == SECTION_INFO || magic == MIX_SECTION_INFO) >> + if (magic == SECTION_INFO || magic == MIX_SECTION_INFO) { >> + kmemleak_free_part(page_to_virt(page), PAGE_SIZE); >> put_page_bootmem(page); >> - else >> + } else >> VM_BUG_ON_PAGE(1, page); >> } >> #else >> -- >> 2.25.1 >> >> > . >