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=-6.5 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLACK,URIBL_BLOCKED autolearn=no 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 BFCD1C4363D for ; Tue, 22 Sep 2020 17:00:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 82BEC23A34 for ; Tue, 22 Sep 2020 17:00:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1600794041; bh=iSMSqB+GWIh7ZpV1xDbeA/Vqh+G1QW/MiQi/XWqannY=; h=Date:From:To:Subject:Reply-To:List-ID:From; b=pHB3j/SAkIChUwFVmcq998cyLytcAbj4ymjvZGjvjlIj6ysGMs+TZXmVoLpnt1PAJ RjEqUMAFM+/yDlM+80WiYp/lNgRBCGob24kwbqsfsPUcPZOKmFVZak0TVOpP/mRbm0 1nKqIUh/spKFk8d5N7gy0Hw5PJWtd8+VkJymVFpA= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726629AbgIVRAl (ORCPT ); Tue, 22 Sep 2020 13:00:41 -0400 Received: from mail.kernel.org ([198.145.29.99]:45204 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726607AbgIVRAl (ORCPT ); Tue, 22 Sep 2020 13:00:41 -0400 Received: from X1 (unknown [216.241.194.61]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id E8A8A20888; Tue, 22 Sep 2020 17:00:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1600794040; bh=iSMSqB+GWIh7ZpV1xDbeA/Vqh+G1QW/MiQi/XWqannY=; h=Date:From:To:Subject:From; b=vEoKvvlJnYsEJcBmB4Zdo9D0oL3S8dR4hNEVT5yhDB4mX0Uf+xCF8O1rExS+B+EHa 7npQxFJgChQ4G8NL+KJgXBN0zRbiPAjdkyJE7Ijex2E0/WS5KCeHumEQUk2DWpIFds a5msm1xigB0U0UgmRrOSn7krFGJOkXQVCHIWHuTw= Date: Tue, 22 Sep 2020 10:00:39 -0700 From: akpm@linux-foundation.org To: mm-commits@vger.kernel.org, zeil@yandex-team.ru, tony.luck@intel.com, osalvador@suse.com, naoya.horiguchi@nec.com, mike.kravetz@oracle.com, mhocko@kernel.org, david@redhat.com, dave.hansen@intel.com, cai@lca.pw, aris@ruivo.org, aneesh.kumar@linux.vnet.ibm.com, aneesh.kumar@linux.ibm.com, osalvador@suse.de Subject: + mmhwpoison-return-0-if-the-page-is-already-poisoned-in-soft-offline.patch added to -mm tree Message-ID: <20200922170039.hPGU8%akpm@linux-foundation.org> User-Agent: s-nail v14.9.10 Precedence: bulk Reply-To: linux-kernel@vger.kernel.org List-ID: X-Mailing-List: mm-commits@vger.kernel.org The patch titled Subject: mm,hwpoison: return 0 if the page is already poisoned in soft-offline has been added to the -mm tree. Its filename is mmhwpoison-return-0-if-the-page-is-already-poisoned-in-soft-offline.patch This patch should soon appear at https://ozlabs.org/~akpm/mmots/broken-out/mmhwpoison-return-0-if-the-page-is-already-poisoned-in-soft-offline.patch and later at https://ozlabs.org/~akpm/mmotm/broken-out/mmhwpoison-return-0-if-the-page-is-already-poisoned-in-soft-offline.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next and is updated there every 3-4 working days ------------------------------------------------------ From: Oscar Salvador Subject: mm,hwpoison: return 0 if the page is already poisoned in soft-offline 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. Link: https://lkml.kernel.org/r/20200922135650.1634-12-osalvador@suse.de Signed-off-by: Oscar Salvador Cc: "Aneesh Kumar K.V" Cc: Aneesh Kumar K.V Cc: Aristeu Rozanski Cc: Dave Hansen Cc: David Hildenbrand Cc: Dmitry Yakunin Cc: Michal Hocko Cc: Mike Kravetz Cc: Naoya Horiguchi Cc: Oscar Salvador Cc: Qian Cai Cc: Tony Luck Signed-off-by: Andrew Morton --- mm/madvise.c | 5 ----- mm/memory-failure.c | 4 ++-- 2 files changed, 2 insertions(+), 7 deletions(-) --- a/mm/madvise.c~mmhwpoison-return-0-if-the-page-is-already-poisoned-in-soft-offline +++ a/mm/madvise.c @@ -896,11 +896,6 @@ static int madvise_inject_error(int beha */ 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); --- a/mm/memory-failure.c~mmhwpoison-return-0-if-the-page-is-already-poisoned-in-soft-offline +++ a/mm/memory-failure.c @@ -1802,7 +1802,7 @@ static int __soft_offline_page(struct pa 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, 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(); _ Patches currently in -mm which might be from osalvador@suse.de are mmhwpoison-unexport-get_hwpoison_page-and-make-it-static.patch mmhwpoison-refactor-madvise_inject_error.patch mmhwpoison-kill-put_hwpoison_page.patch mmhwpoison-unify-thp-handling-for-hard-and-soft-offline.patch mmhwpoison-rework-soft-offline-for-free-pages.patch mmhwpoison-rework-soft-offline-for-in-use-pages.patch mmhwpoison-refactor-soft_offline_huge_page-and-__soft_offline_page.patch mmhwpoison-return-0-if-the-page-is-already-poisoned-in-soft-offline.patch mmhwpoison-try-to-narrow-window-race-for-free-pages.patch mmhwpoison-take-free-pages-off-the-buddy-freelists.patch mmhwpoison-drain-pcplists-before-bailing-out-for-non-buddy-zero-refcount-page.patch mmhwpoison-drop-unneeded-pcplist-draining.patch mmhwpoison-remove-stale-code.patch