From nobody Sat Apr 11 17:08:50 2026 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 89A22C19F2D for ; Tue, 9 Aug 2022 06:54:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234542AbiHIGyk (ORCPT ); Tue, 9 Aug 2022 02:54:40 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58538 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229606AbiHIGyh (ORCPT ); Tue, 9 Aug 2022 02:54:37 -0400 Received: from szxga02-in.huawei.com (szxga02-in.huawei.com [45.249.212.188]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 49661201BD for ; Mon, 8 Aug 2022 23:54:36 -0700 (PDT) Received: from dggemv703-chm.china.huawei.com (unknown [172.30.72.55]) by szxga02-in.huawei.com (SkyGuard) with ESMTP id 4M23dV0PqZzlVqJ; Tue, 9 Aug 2022 14:51:42 +0800 (CST) Received: from kwepemm600013.china.huawei.com (7.193.23.68) by dggemv703-chm.china.huawei.com (10.3.19.46) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.24; Tue, 9 Aug 2022 14:54:33 +0800 Received: from huawei.com (10.175.127.227) by kwepemm600013.china.huawei.com (7.193.23.68) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.24; Tue, 9 Aug 2022 14:54:32 +0800 From: Zhihao Cheng To: , , , , CC: , , , Subject: [PATCH] ubi: fastmap: Fix missed fm_anchor PEB in wear-leveling after disabling fastmap Date: Tue, 9 Aug 2022 15:06:19 +0800 Message-ID: <20220809070619.1565447-1-chengzhihao1@huawei.com> X-Mailer: git-send-email 2.31.1 MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Originating-IP: [10.175.127.227] X-ClientProxiedBy: dggems702-chm.china.huawei.com (10.3.19.179) To kwepemm600013.china.huawei.com (7.193.23.68) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" After disabling fastmap(ubi->fm_disabled =3D 1), fastmap won't be updated, fm_anchor PEB is missed being scheduled for erasing. Besides, fm_anchor PEB may have smallest erase count, it doesn't participate wear-leveling. The difference of erase count between fm_anchor PEB and other PEBs will be larger and larger later on. In which situation fastmap can be disabled? Initially, we have an UBI image with fastmap. Then the image will be atttached without module parameter 'fm_autoconvert', ubi turns to full scanning mode in one random attaching process(eg. bad fastmap caused by powercut), ubi fastmap is disabled since then. Fix it by not getting fm_anchor if fastmap is disabled in ubi_refill_pools(). Fetch a reproducer in [Link]. Link: https://bugzilla.kernel.org/show_bug.cgi?id=3D216341 Fixes: 4b68bf9a69d22d ("ubi: Select fastmap anchor PEBs considering ...") Signed-off-by: Zhihao Cheng --- drivers/mtd/ubi/fastmap-wl.c | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-) diff --git a/drivers/mtd/ubi/fastmap-wl.c b/drivers/mtd/ubi/fastmap-wl.c index 0ee452275578..863f571f1adb 100644 --- a/drivers/mtd/ubi/fastmap-wl.c +++ b/drivers/mtd/ubi/fastmap-wl.c @@ -146,13 +146,15 @@ void ubi_refill_pools(struct ubi_device *ubi) if (ubi->fm_anchor) { wl_tree_add(ubi->fm_anchor, &ubi->free); ubi->free_count++; + ubi->fm_anchor =3D NULL; } =20 - /* - * All available PEBs are in ubi->free, now is the time to get - * the best anchor PEBs. - */ - ubi->fm_anchor =3D ubi_wl_get_fm_peb(ubi, 1); + if (!ubi->fm_disabled) + /* + * All available PEBs are in ubi->free, now is the time to get + * the best anchor PEBs. + */ + ubi->fm_anchor =3D ubi_wl_get_fm_peb(ubi, 1); =20 for (;;) { enough =3D 0; --=20 2.31.1