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 X-Spam-Level: X-Spam-Status: No, score=-12.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT 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 10750C4363D for ; Tue, 22 Sep 2020 13:57:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D42F220719 for ; Tue, 22 Sep 2020 13:57:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726810AbgIVN5m (ORCPT ); Tue, 22 Sep 2020 09:57:42 -0400 Received: from mx2.suse.de ([195.135.220.15]:33670 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726723AbgIVN5L (ORCPT ); Tue, 22 Sep 2020 09:57:11 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id 8D086AFF7; Tue, 22 Sep 2020 13:57:47 +0000 (UTC) From: Oscar Salvador To: akpm@linux-foundation.org Cc: aris@ruivo.org, naoya.horiguchi@nec.com, mhocko@kernel.org, tony.luck@intel.com, cai@lca.pw, linux-kernel@vger.kernel.org, linux-mm@kvack.org, Oscar Salvador Subject: [PATCH v7 11/14] mm,hwpoison: return 0 if the page is already poisoned in soft-offline Date: Tue, 22 Sep 2020 15:56:47 +0200 Message-Id: <20200922135650.1634-12-osalvador@suse.de> X-Mailer: git-send-email 2.13.7 In-Reply-To: <20200922135650.1634-1-osalvador@suse.de> References: <20200922135650.1634-1-osalvador@suse.de> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Currently, there is an inconsistency when calling soft-offline from different paths on a page that is already poisoned. 1) madvise: madvise_inject_error skips any poisoned page and continues the loop. If that was the only page to madvise, it returns 0. 2) /sys/devices/system/memory/: When calling soft_offline_page_store()->soft_offline_page(), we return -EBUSY in case the page is already poisoned. This is inconsistent with a) the above example and b) memory_failure, where we return 0 if the page was poisoned. Fix this by dropping the PageHWPoison() check in madvise_inject_error, and let soft_offline_page return 0 if it finds the page already poisoned. Please, note that this represents a user-api change, since now the return error when calling soft_offline_page_store()->soft_offline_page() will be different. Signed-off-by: Oscar Salvador --- mm/madvise.c | 5 ----- mm/memory-failure.c | 4 ++-- 2 files changed, 2 insertions(+), 7 deletions(-) diff --git a/mm/madvise.c b/mm/madvise.c index f3a86d547ceb..5ab978b828f0 100644 --- a/mm/madvise.c +++ b/mm/madvise.c @@ -896,11 +896,6 @@ static int madvise_inject_error(int behavior, */ size = page_size(compound_head(page)); - if (PageHWPoison(page)) { - put_page(page); - continue; - } - if (behavior == MADV_SOFT_OFFLINE) { pr_info("Soft offlining pfn %#lx at process virtual address %#lx\n", pfn, start); diff --git a/mm/memory-failure.c b/mm/memory-failure.c index 7c122cca9f31..087f070b06b5 100644 --- a/mm/memory-failure.c +++ b/mm/memory-failure.c @@ -1802,7 +1802,7 @@ static int __soft_offline_page(struct page *page) unlock_page(page); put_page(page); pr_info("soft offline: %#lx page already poisoned\n", pfn); - return -EBUSY; + return 0; } if (!PageHuge(page)) @@ -1906,7 +1906,7 @@ int soft_offline_page(unsigned long pfn, int flags) pr_info("soft offline: %#lx page already poisoned\n", pfn); if (flags & MF_COUNT_INCREASED) put_page(page); - return -EBUSY; + return 0; } get_online_mems(); -- 2.26.2