From nobody Sun Dec 14 19:12:11 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 9AF0C15E81C for ; Fri, 10 May 2024 06:26:29 +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=1715322392; cv=none; b=hjudrtw6HA+UaPajfA4OHBwSUi4VZdvUDgHUOwLYvcrxtry1KQewlYZk5EcbyulruCnLLHhbNqzsY8Yi4J7lwRyDihnMqOFJHnPL1nJLXaibc2tA9C1yhT03JHLPITgifi3gwJ8tdZJADJZ8KhhBIE5TrDkivh1Z0qpPlJocXDw= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1715322392; c=relaxed/simple; bh=6F7CRpnGxqd3OYJM6ibrRjnqycdGgS1RVcWPgGIsFnE=; h=From:To:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=spidLgmhOlxMnwQ0zrJEGm+tgMTdCgPYZuf+5yNQUIJL/d+gqKvAr5GHZujQ8hq3f8GHxTZYd8meNFBrqp9PZ7lSQ+3rV+PZxm4AIdiLxgcddbUIXNrkU8einCOxVjPLSy5s/mJb7hp16R6X8+zVrEKt0Nm8YFHA1Y6zLq1gWTk= 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=HDxOCPWi; 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="HDxOCPWi" Received: from pps.filterd (m0246617.ppops.net [127.0.0.1]) by mx0b-00069f02.pphosted.com (8.17.1.19/8.17.1.19) with ESMTP id 44A60k6V028599; Fri, 10 May 2024 06:26:16 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=lidB/7GHuLOyvJaPSOUYyS3tm5icKkY717K7DeJTTTk=; b=HDxOCPWiFx5b+6+Aqn8kT94s6kd9HF/0Ec97tE1bjkoOyRt5Byl1pgUDij2aImMhHN+1 DYqIowMPMJnAGFbAZp6ZAL2yEf6uaTNDO961feviqzGH1J6IFoOrmCVN4lDsEunTQcV7 3/lfACmxlDsxsJzTJ8ARhK/5ujjEKMmgo35U0n2bv9LZtiM4PCyJKNwmnML9pruZUfQ/ 7DVEd4iR0ch5rJ1kV+c450Lab7aPIKoi+5KKUR3ecpHw+LRxxW1jp+thn5unqYbMY4+F I2iCZ0kR/rGHbPoagtEqJr8k/0yEVqYABR47/SdzhIv1kUEi9QNorEVhNZbkKblynn2U QQ== Received: from iadpaimrmta01.imrmtpd1.prodappiadaev1.oraclevcn.com (iadpaimrmta01.appoci.oracle.com [130.35.100.223]) by mx0b-00069f02.pphosted.com (PPS) with ESMTPS id 3y1dfsr44y-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 10 May 2024 06:26:15 +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 44A5vUjH020104; Fri, 10 May 2024 06:26:14 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-2; Fri, 10 May 2024 06:26:14 +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 1/5] mm/memory-failure: try to send SIGBUS even if unmap failed Date: Fri, 10 May 2024 00:25:58 -0600 Message-Id: <20240510062602.901510-2-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-GUID: KM_HUVbH9r9GCli7EIF_tqSVgZdQSVFi X-Proofpoint-ORIG-GUID: KM_HUVbH9r9GCli7EIF_tqSVgZdQSVFi Content-Type: text/plain; charset="utf-8" For years when it comes down to kill a process due to hwpoison, a SIGBUS is delivered only if unmap has been successful. Otherwise, a SIGKILL is delivered. And the reason for that is to prevent the involved process from accessing the hwpoisoned page again. Since then a lot has changed, a hwpoisoned page is marked and upon being re-accessed, the memory-failure handler invokes kill_accessing_process() to kill the process immediately. So let's take out the '!unmap_success' factor and try to deliver SIGBUS if possible. Signed-off-by: Jane Chu Reviewed-by: Oscar Salvador Acked-by: Miaohe Lin --- mm/memory-failure.c | 15 ++++----------- 1 file changed, 4 insertions(+), 11 deletions(-) diff --git a/mm/memory-failure.c b/mm/memory-failure.c index 16ada4fb02b7..739311e121af 100644 --- a/mm/memory-failure.c +++ b/mm/memory-failure.c @@ -514,22 +514,15 @@ void add_to_kill_ksm(struct task_struct *tsk, struct = page *p, * * Only do anything when FORCEKILL is set, otherwise just free the * list (this is used for clean pages which do not need killing) - * Also when FAIL is set do a force kill because something went - * wrong earlier. */ -static void kill_procs(struct list_head *to_kill, int forcekill, bool fail, +static void kill_procs(struct list_head *to_kill, int forcekill, unsigned long pfn, int flags) { struct to_kill *tk, *next; =20 list_for_each_entry_safe(tk, next, to_kill, nd) { if (forcekill) { - /* - * In case something went wrong with munmapping - * make sure the process doesn't catch the - * signal and then access the memory. Just kill it. - */ - if (fail || tk->addr =3D=3D -EFAULT) { + if (tk->addr =3D=3D -EFAULT) { pr_err("%#lx: forcibly killing %s:%d because of failure to unmap corru= pted page\n", pfn, tk->tsk->comm, tk->tsk->pid); do_send_sig_info(SIGKILL, SEND_SIG_PRIV, @@ -1660,7 +1653,7 @@ static bool hwpoison_user_mappings(struct folio *foli= o, struct page *p, */ forcekill =3D folio_test_dirty(folio) || (flags & MF_MUST_KILL) || !unmap_success; - kill_procs(&tokill, forcekill, !unmap_success, pfn, flags); + kill_procs(&tokill, forcekill, pfn, flags); =20 return unmap_success; } @@ -1724,7 +1717,7 @@ static void unmap_and_kill(struct list_head *to_kill,= unsigned long pfn, unmap_mapping_range(mapping, start, size, 0); } =20 - kill_procs(to_kill, flags & MF_MUST_KILL, false, pfn, flags); + kill_procs(to_kill, flags & MF_MUST_KILL, pfn, flags); } =20 /* --=20 2.39.3