From nobody Sun Dec 14 19:16:00 2025 Received: from mx0b-00069f02.pphosted.com (mx0b-00069f02.pphosted.com [205.220.177.32]) (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 A000750263 for ; Fri, 24 May 2024 21:53:53 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=205.220.177.32 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1716587635; cv=none; b=JiefFhVpV/kagcEu9YifZJ0Zj53zpr2GhkYp6b84RsAVQYcmYMpnw3KXpTIm3TkujRJV5NCmwWtvbWezKsCYXkjoghyRkuA8OJibAiA/Ur9myFvWZUg5rp8uYba5j04XNnmnJOiOiBGWHkrYaVM1r7417DfyJSuaCPev1TP+zBA= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1716587635; c=relaxed/simple; bh=D7kXXmKbXqjGmHdN4mg/BtutHXoSCD6re2jm29C5YuY=; h=From:To:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=uKbIxgpBeX5F2JbyNIgYcLjZRg+O1edNQQDJPZgGx0Bvew1EZeCiqECC5CLpP8YuBkiSoG/xuX65RGY4+XWJydXSuqGnnUw+7S58uNe557Oj9ri7XZ0kcDcqfUK0jPx+7v3goXzhLMFFGAwSoXI3qsxPzzDVblKCBGcZywPINFE= 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=f0IW7CgH; arc=none smtp.client-ip=205.220.177.32 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="f0IW7CgH" Received: from pps.filterd (m0333520.ppops.net [127.0.0.1]) by mx0b-00069f02.pphosted.com (8.17.1.19/8.17.1.19) with ESMTP id 44OFx1PV020088; Fri, 24 May 2024 21:53:44 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=7HYN1EpHhN8K7/QWXfhCO5Xkdz0SMhL/TG8r2CsGXTY=; b=f0IW7CgHhxEM/jkAAr9fsWvW80EjOTg3U1E+Aunb7J/MnOxa8mzWmn5h8o+z36Ougs1R j7mySjed4aSn7Gj2WGdbKGKSDbyeUBeIJPMJ1ixkjbIe8AMwpxH1cQEhQ3bdjQk285MI uMCFag5BEhdMzWUituxLxLmpPr7qXrV9fkXyHeB+Foy19xBnGYm4LsWk9yYW0ljxREXl Y4I54CbIY1NB2m7nngKDmzJWwmnDIOwrrm1CSQTb1aV5ZGkysrq2rit8nPt3+aIpAWlj AKFIg9WwBL26PdNS9zBStJOBfx6FuwC7d08Zspm4khQP5eFIJbH1BGH8975OJFIIXm2l QQ== Received: from phxpaimrmta01.imrmtpd1.prodappphxaev1.oraclevcn.com (phxpaimrmta01.appoci.oracle.com [138.1.114.2]) by mx0b-00069f02.pphosted.com (PPS) with ESMTPS id 3y6mce5h56-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 24 May 2024 21:53:43 +0000 Received: from pps.filterd (phxpaimrmta01.imrmtpd1.prodappphxaev1.oraclevcn.com [127.0.0.1]) by phxpaimrmta01.imrmtpd1.prodappphxaev1.oraclevcn.com (8.17.1.19/8.17.1.19) with ESMTP id 44OLjG1C035956; Fri, 24 May 2024 21:53:42 GMT Received: from brm-x62-16.us.oracle.com (brm-x62-16.us.oracle.com [10.80.150.37]) by phxpaimrmta01.imrmtpd1.prodappphxaev1.oraclevcn.com (PPS) with ESMTP id 3y6jscbsu0-4; Fri, 24 May 2024 21:53:42 +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 v4 3/5] mm/memory-failure: improve memory failure action_result messages Date: Fri, 24 May 2024 15:53:04 -0600 Message-Id: <20240524215306.2705454-4-jane.chu@oracle.com> X-Mailer: git-send-email 2.39.3 In-Reply-To: <20240524215306.2705454-1-jane.chu@oracle.com> References: <20240524215306.2705454-1-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:17.12.28.16 definitions=2024-05-24_08,2024-05-24_01,2024-05-17_01 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 phishscore=0 mlxscore=0 spamscore=0 mlxlogscore=940 adultscore=0 bulkscore=0 suspectscore=0 malwarescore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2405010000 definitions=main-2405240158 X-Proofpoint-ORIG-GUID: _mdySqjhmz_UPwiin9TJeXbOJ1k2kgS6 X-Proofpoint-GUID: _mdySqjhmz_UPwiin9TJeXbOJ1k2kgS6 Content-Type: text/plain; charset="utf-8" Added two explicit MF_MSG messages describing failure in get_hwpoison_page. Attemped to document the definition of various action names, and made a few adjustment to the action_result() calls. Signed-off-by: Jane Chu Reviewed-by: Oscar Salvador Acked-by: Miaohe Lin --- include/linux/mm.h | 2 ++ include/ras/ras_event.h | 2 ++ mm/memory-failure.c | 37 ++++++++++++++++++++++++++++++++----- 3 files changed, 36 insertions(+), 5 deletions(-) diff --git a/include/linux/mm.h b/include/linux/mm.h index 9849dfda44d4..b4598c6a393a 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -4111,6 +4111,7 @@ enum mf_action_page_type { MF_MSG_DIFFERENT_COMPOUND, MF_MSG_HUGE, MF_MSG_FREE_HUGE, + MF_MSG_GET_HWPOISON, MF_MSG_UNMAP_FAILED, MF_MSG_DIRTY_SWAPCACHE, MF_MSG_CLEAN_SWAPCACHE, @@ -4124,6 +4125,7 @@ enum mf_action_page_type { MF_MSG_BUDDY, MF_MSG_DAX, MF_MSG_UNSPLIT_THP, + MF_MSG_ALREADY_POISONED, MF_MSG_UNKNOWN, }; =20 diff --git a/include/ras/ras_event.h b/include/ras/ras_event.h index c011ea236e9b..b3f6832a94fe 100644 --- a/include/ras/ras_event.h +++ b/include/ras/ras_event.h @@ -360,6 +360,7 @@ TRACE_EVENT(aer_event, EM ( MF_MSG_DIFFERENT_COMPOUND, "different compound page after locking" )= \ EM ( MF_MSG_HUGE, "huge page" ) \ EM ( MF_MSG_FREE_HUGE, "free huge page" ) \ + EM ( MF_MSG_GET_HWPOISON, "get hwpoison page" ) \ EM ( MF_MSG_UNMAP_FAILED, "unmapping failed page" ) \ EM ( MF_MSG_DIRTY_SWAPCACHE, "dirty swapcache page" ) \ EM ( MF_MSG_CLEAN_SWAPCACHE, "clean swapcache page" ) \ @@ -373,6 +374,7 @@ TRACE_EVENT(aer_event, EM ( MF_MSG_BUDDY, "free buddy page" ) \ EM ( MF_MSG_DAX, "dax page" ) \ EM ( MF_MSG_UNSPLIT_THP, "unsplit thp" ) \ + EM ( MF_MSG_ALREADY_POISONED, "already poisoned" ) \ EMe ( MF_MSG_UNKNOWN, "unknown page" ) =20 /* diff --git a/mm/memory-failure.c b/mm/memory-failure.c index 739311e121af..d1fb1d6f6b11 100644 --- a/mm/memory-failure.c +++ b/mm/memory-failure.c @@ -879,6 +879,28 @@ static int kill_accessing_process(struct task_struct *= p, unsigned long pfn, return ret > 0 ? -EHWPOISON : -EFAULT; } =20 +/* + * MF_IGNORED - The m-f() handler marks the page as PG_hwpoisoned'ed. + * But it could not do more to isolate the page from being accessed again, + * nor does it kill the process. This is extremely rare and one of the + * potential causes is that the page state has been changed due to + * underlying race condition. This is the most severe outcomes. + * + * MF_FAILED - The m-f() handler marks the page as PG_hwpoisoned'ed. + * It should have killed the process, but it can't isolate the page, + * due to conditions such as extra pin, unmap failure, etc. Accessing + * the page again may trigger another MCE and the process will be killed + * by the m-f() handler immediately. + * + * MF_DELAYED - The m-f() handler marks the page as PG_hwpoisoned'ed. + * The page is unmapped, and is removed from the LRU or file mapping. + * An attempt to access the page again will trigger page fault and the + * PF handler will kill the process. + * + * MF_RECOVERED - The m-f() handler marks the page as PG_hwpoisoned'ed. + * The page has been completely isolated, that is, unmapped, taken out of + * the buddy system, or hole-punnched out of the file mapping. + */ static const char *action_name[] =3D { [MF_IGNORED] =3D "Ignored", [MF_FAILED] =3D "Failed", @@ -893,6 +915,7 @@ static const char * const action_page_types[] =3D { [MF_MSG_DIFFERENT_COMPOUND] =3D "different compound page after locking", [MF_MSG_HUGE] =3D "huge page", [MF_MSG_FREE_HUGE] =3D "free huge page", + [MF_MSG_GET_HWPOISON] =3D "get hwpoison page", [MF_MSG_UNMAP_FAILED] =3D "unmapping failed page", [MF_MSG_DIRTY_SWAPCACHE] =3D "dirty swapcache page", [MF_MSG_CLEAN_SWAPCACHE] =3D "clean swapcache page", @@ -906,6 +929,7 @@ static const char * const action_page_types[] =3D { [MF_MSG_BUDDY] =3D "free buddy page", [MF_MSG_DAX] =3D "dax page", [MF_MSG_UNSPLIT_THP] =3D "unsplit thp", + [MF_MSG_ALREADY_POISONED] =3D "already poisoned", [MF_MSG_UNKNOWN] =3D "unknown page", }; =20 @@ -1013,12 +1037,13 @@ static int me_kernel(struct page_state *ps, struct = page *p) =20 /* * Page in unknown state. Do nothing. + * This is a catch-all in case we fail to make sense of the page state. */ static int me_unknown(struct page_state *ps, struct page *p) { pr_err("%#lx: Unknown page state\n", page_to_pfn(p)); unlock_page(p); - return MF_FAILED; + return MF_IGNORED; } =20 /* @@ -2055,6 +2080,7 @@ static int try_memory_failure_hugetlb(unsigned long p= fn, int flags, int *hugetlb if (flags & MF_ACTION_REQUIRED) { folio =3D page_folio(p); res =3D kill_accessing_process(current, folio_pfn(folio), flags); + action_result(pfn, MF_MSG_ALREADY_POISONED, MF_FAILED); } return res; } else if (res =3D=3D -EBUSY) { @@ -2062,7 +2088,7 @@ static int try_memory_failure_hugetlb(unsigned long p= fn, int flags, int *hugetlb flags |=3D MF_NO_RETRY; goto retry; } - return action_result(pfn, MF_MSG_UNKNOWN, MF_IGNORED); + return action_result(pfn, MF_MSG_GET_HWPOISON, MF_IGNORED); } =20 folio =3D page_folio(p); @@ -2097,7 +2123,7 @@ static int try_memory_failure_hugetlb(unsigned long p= fn, int flags, int *hugetlb =20 if (!hwpoison_user_mappings(folio, p, pfn, flags)) { folio_unlock(folio); - return action_result(pfn, MF_MSG_UNMAP_FAILED, MF_IGNORED); + return action_result(pfn, MF_MSG_UNMAP_FAILED, MF_FAILED); } =20 return identify_page_state(pfn, p, page_flags); @@ -2231,6 +2257,7 @@ int memory_failure(unsigned long pfn, int flags) res =3D kill_accessing_process(current, pfn, flags); if (flags & MF_COUNT_INCREASED) put_page(p); + action_result(pfn, MF_MSG_ALREADY_POISONED, MF_FAILED); goto unlock_mutex; } =20 @@ -2267,7 +2294,7 @@ int memory_failure(unsigned long pfn, int flags) } goto unlock_mutex; } else if (res < 0) { - res =3D action_result(pfn, MF_MSG_UNKNOWN, MF_IGNORED); + res =3D action_result(pfn, MF_MSG_GET_HWPOISON, MF_IGNORED); goto unlock_mutex; } } @@ -2363,7 +2390,7 @@ int memory_failure(unsigned long pfn, int flags) * Abort on fail: __filemap_remove_folio() assumes unmapped page. */ if (!hwpoison_user_mappings(folio, p, pfn, flags)) { - res =3D action_result(pfn, MF_MSG_UNMAP_FAILED, MF_IGNORED); + res =3D action_result(pfn, MF_MSG_UNMAP_FAILED, MF_FAILED); goto unlock_page; } =20 --=20 2.39.3