From patchwork Wed Feb 23 08:21:35 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: luofei X-Patchwork-Id: 12756561 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 32029C433F5 for ; Wed, 23 Feb 2022 08:24:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237670AbiBWIZB (ORCPT ); Wed, 23 Feb 2022 03:25:01 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36686 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231350AbiBWIZB (ORCPT ); Wed, 23 Feb 2022 03:25:01 -0500 Received: from spam.unicloud.com (eage.unicloud.com [220.194.70.58]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D87C65A5A5; Wed, 23 Feb 2022 00:24:32 -0800 (PST) Received: from eage.unicloud.com ([220.194.70.35]) by spam.unicloud.com with ESMTP id 21N8Lh1l031001; Wed, 23 Feb 2022 16:21:43 +0800 (GMT-8) (envelope-from luofei@unicloud.com) Received: from localhost.localdomain (10.10.1.7) by zgys-ex-mb09.Unicloud.com (10.10.0.24) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.2375.17; Wed, 23 Feb 2022 16:21:42 +0800 From: luofei To: , , , , , , , CC: , , , , , , luofei Subject: [PATCH v5 1/2] mm/hwpoison: Avoid the impact of hwpoison_filter() return value on mce handler Date: Wed, 23 Feb 2022 03:21:35 -0500 Message-ID: <20220223082135.2769649-1-luofei@unicloud.com> X-Mailer: git-send-email 2.27.0 MIME-Version: 1.0 X-Originating-IP: [10.10.1.7] X-ClientProxiedBy: zgys-ex-mb08.Unicloud.com (10.10.0.14) To zgys-ex-mb09.Unicloud.com (10.10.0.24) X-DNSRBL: X-MAIL: spam.unicloud.com 21N8Lh1l031001 Precedence: bulk List-ID: X-Mailing-List: linux-edac@vger.kernel.org When the hwpoison page meets the filter conditions, it should not be regarded as successful memory_failure() processing for mce handler, but should return a distinct value, otherwise mce handler regards the error page has been identified and isolated, which may lead to calling set_mce_nospec() to change page attribute, etc. Here memory_failure() return -EOPNOTSUPP to indicate that the error event is filtered, mce handler should not take any action for this situation and hwpoison injector should treat as correct. Signed-off-by: luofei Acked-by: Borislav Petkov --- arch/x86/kernel/cpu/mce/core.c | 8 +++++--- drivers/base/memory.c | 2 ++ mm/hwpoison-inject.c | 3 ++- mm/madvise.c | 2 ++ mm/memory-failure.c | 9 +++++++-- 5 files changed, 18 insertions(+), 6 deletions(-) diff --git a/arch/x86/kernel/cpu/mce/core.c b/arch/x86/kernel/cpu/mce/core.c index 728f3b36ce2d..f4b56904db8a 100644 --- a/arch/x86/kernel/cpu/mce/core.c +++ b/arch/x86/kernel/cpu/mce/core.c @@ -1332,10 +1332,12 @@ static void kill_me_maybe(struct callback_head *cb) /* * -EHWPOISON from memory_failure() means that it already sent SIGBUS - * to the current process with the proper error info, so no need to - * send SIGBUS here again. + * to the current process with the proper error info, + * -EOPNOTSUPP means hwpoison_filter() filtered the error event, + * + * In both cases, no further processing is required. */ - if (ret == -EHWPOISON) + if (ret == -EHWPOISON || ret == -EOPNOTSUPP) return; pr_err("Memory error not recovered"); diff --git a/drivers/base/memory.c b/drivers/base/memory.c index 365cd4a7f239..abf407e45467 100644 --- a/drivers/base/memory.c +++ b/drivers/base/memory.c @@ -555,6 +555,8 @@ static ssize_t hard_offline_page_store(struct device *dev, return -EINVAL; pfn >>= PAGE_SHIFT; ret = memory_failure(pfn, 0); + if (ret == -EOPNOTSUPP) + ret = 0; return ret ? ret : count; } diff --git a/mm/hwpoison-inject.c b/mm/hwpoison-inject.c index aff4d27ec235..a1d6fc3c78b9 100644 --- a/mm/hwpoison-inject.c +++ b/mm/hwpoison-inject.c @@ -48,7 +48,8 @@ static int hwpoison_inject(void *data, u64 val) inject: pr_info("Injecting memory failure at pfn %#lx\n", pfn); - return memory_failure(pfn, 0); + err = memory_failure(pfn, 0); + return (err == -EOPNOTSUPP) ? 0 : err; } static int hwpoison_unpoison(void *data, u64 val) diff --git a/mm/madvise.c b/mm/madvise.c index ae35d72627ef..e7cb7a0751d6 100644 --- a/mm/madvise.c +++ b/mm/madvise.c @@ -1096,6 +1096,8 @@ static int madvise_inject_error(int behavior, pr_info("Injecting memory failure for pfn %#lx at process virtual address %#lx\n", pfn, start); ret = memory_failure(pfn, MF_COUNT_INCREASED); + if (ret == -EOPNOTSUPP) + ret = 0; } if (ret) diff --git a/mm/memory-failure.c b/mm/memory-failure.c index 662afe7b514f..7e16d31df0f3 100644 --- a/mm/memory-failure.c +++ b/mm/memory-failure.c @@ -1528,7 +1528,7 @@ static int memory_failure_hugetlb(unsigned long pfn, int flags) if (TestClearPageHWPoison(head)) num_poisoned_pages_dec(); unlock_page(head); - return 0; + return -EOPNOTSUPP; } unlock_page(head); res = MF_FAILED; @@ -1615,7 +1615,7 @@ static int memory_failure_dev_pagemap(unsigned long pfn, int flags, goto out; if (hwpoison_filter(page)) { - rc = 0; + rc = -EOPNOTSUPP; goto unlock; } @@ -1688,6 +1688,10 @@ static DEFINE_MUTEX(mf_mutex); * * Must run in process context (e.g. a work queue) with interrupts * enabled and no spinlocks hold. + * + * Return: 0 for successfully handled the memory error, + * -EOPNOTSUPP for memory_filter() filtered the error event, + * < 0(except -EOPNOTSUPP) on failure. */ int memory_failure(unsigned long pfn, int flags) { @@ -1843,6 +1847,7 @@ int memory_failure(unsigned long pfn, int flags) num_poisoned_pages_dec(); unlock_page(p); put_page(p); + res = -EOPNOTSUPP; goto unlock_mutex; }