From nobody Tue Feb 10 04:12:39 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 35ADDC0015E for ; Thu, 27 Jul 2023 11:57:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233654AbjG0L5J (ORCPT ); Thu, 27 Jul 2023 07:57:09 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44174 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233589AbjG0L46 (ORCPT ); Thu, 27 Jul 2023 07:56:58 -0400 Received: from szxga01-in.huawei.com (szxga01-in.huawei.com [45.249.212.187]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D0F122D54 for ; Thu, 27 Jul 2023 04:56:54 -0700 (PDT) Received: from canpemm500002.china.huawei.com (unknown [172.30.72.55]) by szxga01-in.huawei.com (SkyGuard) with ESMTP id 4RBTgN0WB2ztRc7; Thu, 27 Jul 2023 19:53:36 +0800 (CST) Received: from huawei.com (10.174.151.185) by canpemm500002.china.huawei.com (7.192.104.244) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.27; Thu, 27 Jul 2023 19:56:51 +0800 From: Miaohe Lin To: , CC: , , , Subject: [PATCH v2 3/4] mm: memory-failure: avoid false hwpoison page mapped error info Date: Thu, 27 Jul 2023 19:56:42 +0800 Message-ID: <20230727115643.639741-4-linmiaohe@huawei.com> X-Mailer: git-send-email 2.33.0 In-Reply-To: <20230727115643.639741-1-linmiaohe@huawei.com> References: <20230727115643.639741-1-linmiaohe@huawei.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Originating-IP: [10.174.151.185] X-ClientProxiedBy: dggems701-chm.china.huawei.com (10.3.19.178) To canpemm500002.china.huawei.com (7.192.104.244) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" folio->_mapcount is overloaded in SLAB, so folio_mapped() has to be done after folio_test_slab() is checked. Otherwise slab folio might be treated as a mapped folio leading to false 'Someone maps the hwpoison page' error info. Fixes: 230ac719c500 ("mm/hwpoison: don't try to unpoison containment-failed= pages") Signed-off-by: Miaohe Lin Reviewed-by: Matthew Wilcox (Oracle) Acked-by: Naoya Horiguchi --- mm/memory-failure.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) diff --git a/mm/memory-failure.c b/mm/memory-failure.c index 4a3e88c15631..d975a6b224f7 100644 --- a/mm/memory-failure.c +++ b/mm/memory-failure.c @@ -2535,6 +2535,13 @@ int unpoison_memory(unsigned long pfn) goto unlock_mutex; } =20 + if (folio_test_slab(folio) || PageTable(&folio->page) || folio_test_reser= ved(folio)) + goto unlock_mutex; + + /* + * Note that folio->_mapcount is overloaded in SLAB, so the simple test + * in folio_mapped() has to be done after folio_test_slab() is checked. + */ if (folio_mapped(folio)) { unpoison_pr_info("Unpoison: Someone maps the hwpoison page %#lx\n", pfn, &unpoison_rs); @@ -2547,9 +2554,6 @@ int unpoison_memory(unsigned long pfn) goto unlock_mutex; } =20 - if (folio_test_slab(folio) || PageTable(&folio->page) || folio_test_reser= ved(folio)) - goto unlock_mutex; - ghp =3D get_hwpoison_page(p, MF_UNPOISON); if (!ghp) { if (PageHuge(p)) { --=20 2.33.0