From nobody Sun Dec 14 18:57:10 2025 Received: from mx0a-00069f02.pphosted.com (mx0a-00069f02.pphosted.com [205.220.165.32]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 1F23C1649DD for ; Fri, 10 May 2024 06:26:35 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=205.220.165.32 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1715322397; cv=none; b=L59aXli8X4BWAMa81722XuR6nlESUNkmKoLwFt2XDJj5LoKzGEMoHz6/Am0Gp6DTNRw0JrsJXLnhnUryUkyS6YGx7/UCw7Q5wJaqUfRC6XsdzFYA7nPhRUc+LIxtuvLbYgfjbLO1fCcDS/Y1zrnVVZM3F3UK2M7Z0GQo1dNfoo4= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1715322397; c=relaxed/simple; bh=wCzAosb9yCwghwfxx/CGqsZgf9AZk6yq9vaFDYv2tRY=; h=From:To:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=qDWn7sPFwpgBAt7YkrB7vYGrRXXwbSdi5fFki+HQjX6JtsN+E+IjoWrtbhVv9/2ZJ0VgWEqORfimdbpYBE0t+TjJ5WH4qhfrwrnIKmZ18ZsbSxVZ+9cFqmE7BSi33EB+apWqDmHz5aVSxtUGkK2ypJNutmOA02/r7w3G3zbUxpM= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=oracle.com; spf=pass smtp.mailfrom=oracle.com; dkim=pass (2048-bit key) header.d=oracle.com header.i=@oracle.com header.b=g+GG0Ikx; arc=none smtp.client-ip=205.220.165.32 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=oracle.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=oracle.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=oracle.com header.i=@oracle.com header.b="g+GG0Ikx" Received: from pps.filterd (m0333521.ppops.net [127.0.0.1]) by mx0b-00069f02.pphosted.com (8.17.1.19/8.17.1.19) with ESMTP id 44A6MlnA021258; Fri, 10 May 2024 06:26:26 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=from : to : subject : date : message-id : in-reply-to : references : mime-version : content-transfer-encoding; s=corp-2023-11-20; bh=tFRwwH8vMdoczPoQRYMz5N41Zt2owkILdQOhrik+iU8=; b=g+GG0IkxeBwWGSyuHfsSdSx+LFncqCu5jZOcbVaDHmkL9ozkB8xCjsgtm+GrDkXmTUj5 MXoy9msQbB+PCutyZxq+HAKT2pUU8SvxyEZ2h8S8G7Zgpmx8DuozzcRn3wU88odGNPMW 64+S4Ksxo0HtObmuilQyCk1Bd9sTw/qfkE5mtg1aJGpyp2oOSkUjnFa5aXIRYK5lfYTI vAky1uOu1pEQjAxLxo/Of1rF5SrdrkCi2qS+I3DhHhWoODouj/cHvEGyv5JIMn/0SxtB 9EzEdDUEkS747E2AHQEmFIXqS5giacQ4OQ2QB0t2qfddTjokh/pxF1dkkb3+namnHna6 sA== Received: from iadpaimrmta01.imrmtpd1.prodappiadaev1.oraclevcn.com (iadpaimrmta01.appoci.oracle.com [130.35.100.223]) by mx0b-00069f02.pphosted.com (PPS) with ESMTPS id 3y1e8sr05v-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 10 May 2024 06:26:26 +0000 Received: from pps.filterd (iadpaimrmta01.imrmtpd1.prodappiadaev1.oraclevcn.com [127.0.0.1]) by iadpaimrmta01.imrmtpd1.prodappiadaev1.oraclevcn.com (8.17.1.19/8.17.1.19) with ESMTP id 44A5vUjP020104; Fri, 10 May 2024 06:26:24 GMT Received: from brm-x62-16.us.oracle.com (brm-x62-16.us.oracle.com [10.80.150.37]) by iadpaimrmta01.imrmtpd1.prodappiadaev1.oraclevcn.com (PPS) with ESMTP id 3xysfpghcd-6; Fri, 10 May 2024 06:26:24 +0000 From: Jane Chu To: linmiaohe@huawei.com, nao.horiguchi@gmail.com, akpm@linux-foundation.org, osalvador@suse.de, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: [PATCH v2 5/5] mm/memory-failure: send SIGBUS in the event of thp split fail Date: Fri, 10 May 2024 00:26:02 -0600 Message-Id: <20240510062602.901510-6-jane.chu@oracle.com> X-Mailer: git-send-email 2.39.3 In-Reply-To: <20240510062602.901510-1-jane.chu@oracle.com> References: <20240510062602.901510-1-jane.chu@oracle.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1039,Hydra:6.0.650,FMLib:17.11.176.26 definitions=2024-05-10_04,2024-05-10_01,2023-05-22_02 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 bulkscore=0 adultscore=0 malwarescore=0 mlxlogscore=999 phishscore=0 mlxscore=0 suspectscore=0 spamscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2405010000 definitions=main-2405100044 X-Proofpoint-ORIG-GUID: Bbu3oqFBFYt86uLCdWySG1px70G6up9M X-Proofpoint-GUID: Bbu3oqFBFYt86uLCdWySG1px70G6up9M Content-Type: text/plain; charset="utf-8" When handle hwpoison in a RDMA longterm pinned thp page, try_to_split_thp_page() will fail. And at this point, there is little else the kernel could do except sending a SIGBUS to the user process, thus give it a chance to recover. Signed-off-by: Jane Chu --- mm/memory-failure.c | 31 ++++++++++++++++++++++++++----- 1 file changed, 26 insertions(+), 5 deletions(-) diff --git a/mm/memory-failure.c b/mm/memory-failure.c index 2fa884d8b5a3..15bb1c0c42e8 100644 --- a/mm/memory-failure.c +++ b/mm/memory-failure.c @@ -1697,7 +1697,7 @@ static int identify_page_state(unsigned long pfn, str= uct page *p, return page_action(ps, p, pfn); } =20 -static int try_to_split_thp_page(struct page *page) +static int try_to_split_thp_page(struct page *page, bool release) { int ret; =20 @@ -1705,7 +1705,7 @@ static int try_to_split_thp_page(struct page *page) ret =3D split_huge_page(page); unlock_page(page); =20 - if (unlikely(ret)) + if (ret && release) put_page(page); =20 return ret; @@ -2177,6 +2177,24 @@ static int memory_failure_dev_pagemap(unsigned long = pfn, int flags, return rc; } =20 +/* + * The calling condition is as such: thp split failed, page might have + * been RDMA pinned, not much can be done for recovery. + * But a SIGBUS should be delivered with vaddr provided so that the user + * application has a chance to recover. Also, application processes' + * election for MCE early killed will be honored. + */ +static int kill_procs_now(struct page *p, unsigned long pfn, int flags, + struct folio *folio) +{ + LIST_HEAD(tokill); + + collect_procs(folio, p, &tokill, flags & MF_ACTION_REQUIRED); + kill_procs(&tokill, true, pfn, flags); + + return -EHWPOISON; +} + /** * memory_failure - Handle memory failure of a page. * @pfn: Page Number of the corrupted page @@ -2313,8 +2331,11 @@ int memory_failure(unsigned long pfn, int flags) * page is a valid handlable page. */ folio_set_has_hwpoisoned(folio); - if (try_to_split_thp_page(p) < 0) { - res =3D action_result(pfn, MF_MSG_UNSPLIT_THP, MF_IGNORED); + if (try_to_split_thp_page(p, false) < 0) { + pr_err("%#lx: thp split failed\n", pfn); + res =3D kill_procs_now(p, pfn, flags, folio); + put_page(p); + res =3D action_result(pfn, MF_MSG_UNSPLIT_THP, MF_FAILED); goto unlock_mutex; } VM_BUG_ON_PAGE(!page_count(p), p); @@ -2688,7 +2709,7 @@ static int soft_offline_in_use_page(struct page *page) }; =20 if (!huge && folio_test_large(folio)) { - if (try_to_split_thp_page(page)) { + if (try_to_split_thp_page(page, true)) { pr_info("soft offline: %#lx: thp split failed\n", pfn); return -EBUSY; } --=20 2.39.3