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 AAFF6C433F5 for ; Sat, 9 Apr 2022 07:38:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240524AbiDIHk5 (ORCPT ); Sat, 9 Apr 2022 03:40:57 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44230 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238676AbiDIHkk (ORCPT ); Sat, 9 Apr 2022 03:40:40 -0400 Received: from szxga01-in.huawei.com (szxga01-in.huawei.com [45.249.212.187]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 12AF3167C3 for ; Sat, 9 Apr 2022 00:38:33 -0700 (PDT) Received: from canpemm500002.china.huawei.com (unknown [172.30.72.54]) by szxga01-in.huawei.com (SkyGuard) with ESMTP id 4Kb6Pn6S06zgYWT; Sat, 9 Apr 2022 15:36:45 +0800 (CST) Received: from huawei.com (10.175.124.27) 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 15.1.2375.24; Sat, 9 Apr 2022 15:38:31 +0800 From: Miaohe Lin To: CC: , , , , , , , , , , , , , , , , , , , Subject: [PATCH 3/4] mm/migration: return errno when isolate_huge_page failed Date: Sat, 9 Apr 2022 15:38:45 +0800 Message-ID: <20220409073846.22286-4-linmiaohe@huawei.com> X-Mailer: git-send-email 2.23.0 In-Reply-To: <20220409073846.22286-1-linmiaohe@huawei.com> References: <20220409073846.22286-1-linmiaohe@huawei.com> MIME-Version: 1.0 Content-Transfer-Encoding: 7BIT Content-Type: text/plain; charset=US-ASCII X-Originating-IP: [10.175.124.27] X-ClientProxiedBy: dggems705-chm.china.huawei.com (10.3.19.182) 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 We might fail to isolate huge page due to e.g. the page is under migration which cleared HPageMigratable. So we should return -EBUSY in this case rather than always return 1 which could confuse the user. Fixes: e8db67eb0ded ("mm: migrate: move_pages() supports thp migration") Reviewed-by: Muchun Song Reviewed-by: Baolin Wang Signed-off-by: Miaohe Lin --- mm/migrate.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) diff --git a/mm/migrate.c b/mm/migrate.c index 381963231a62..044656a14ae2 100644 --- a/mm/migrate.c +++ b/mm/migrate.c @@ -1632,10 +1632,8 @@ static int add_page_for_migration(struct mm_struct *mm, unsigned long addr, goto out_putpage; if (PageHuge(page)) { - if (PageHead(page)) { - isolate_huge_page(page, pagelist); - err = 1; - } + if (PageHead(page)) + err = isolate_huge_page(page, pagelist) ? 1 : -EBUSY; } else { struct page *head; -- 2.23.0