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=-9.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT autolearn=ham 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 A33A6C10DCE for ; Fri, 13 Mar 2020 14:07:58 +0000 (UTC) Received: from lists.ozlabs.org (unknown [203.11.71.2]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 22E3A2072C for ; Fri, 13 Mar 2020 14:07:57 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 22E3A2072C Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.ibm.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Received: from lists.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 48f6wW0vRtzDq6l for ; Sat, 14 Mar 2020 01:07:55 +1100 (AEDT) Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=linux.ibm.com (client-ip=148.163.156.1; helo=mx0a-001b2d01.pphosted.com; envelope-from=ganeshgr@linux.ibm.com; receiver=) Authentication-Results: lists.ozlabs.org; dmarc=none (p=none dis=none) header.from=linux.ibm.com Received: from mx0a-001b2d01.pphosted.com (mx0a-001b2d01.pphosted.com [148.163.156.1]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 48f6s364mdzDqGb for ; Sat, 14 Mar 2020 01:04:49 +1100 (AEDT) Received: from pps.filterd (m0098404.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id 02DE4ORv108269 for ; Fri, 13 Mar 2020 10:04:45 -0400 Received: from e06smtp03.uk.ibm.com (e06smtp03.uk.ibm.com [195.75.94.99]) by mx0a-001b2d01.pphosted.com with ESMTP id 2yr0ch9c3s-1 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NOT) for ; Fri, 13 Mar 2020 10:04:44 -0400 Received: from localhost by e06smtp03.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! 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Violators will be prosecuted; (version=TLSv1/SSLv3 cipher=AES256-GCM-SHA384 bits=256/256) Fri, 13 Mar 2020 14:04:37 -0000 Received: from d06av22.portsmouth.uk.ibm.com (d06av22.portsmouth.uk.ibm.com [9.149.105.58]) by b06cxnps4075.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 02DE4aLX36241650 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 13 Mar 2020 14:04:36 GMT Received: from d06av22.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 787B54C044; Fri, 13 Mar 2020 14:04:36 +0000 (GMT) Received: from d06av22.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 5AC074C046; Fri, 13 Mar 2020 14:04:34 +0000 (GMT) Received: from localhost.localdomain.com (unknown [9.85.90.16]) by d06av22.portsmouth.uk.ibm.com (Postfix) with ESMTP; Fri, 13 Mar 2020 14:04:34 +0000 (GMT) From: Ganesh Goudar To: mpe@ellerman.id.au, linuxppc-dev@lists.ozlabs.org Subject: [PATCH] powerpc/pseries: Fix MCE handling on pseries Date: Fri, 13 Mar 2020 19:34:18 +0530 X-Mailer: git-send-email 2.17.2 X-TM-AS-GCONF: 00 x-cbid: 20031314-0012-0000-0000-000003907E5F X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 20031314-0013-0000-0000-000021CD540E Message-Id: <20200313140418.7940-1-ganeshgr@linux.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.138, 18.0.572 definitions=2020-03-13_05:2020-03-12, 2020-03-13 signatures=0 X-Proofpoint-Spam-Details: rule=outbound_spam_definite policy=outbound score=100 malwarescore=0 clxscore=1011 adultscore=0 mlxlogscore=489 lowpriorityscore=0 suspectscore=0 spamscore=0 impostorscore=0 bulkscore=0 phishscore=0 mlxscore=0 priorityscore=1501 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2003020000 definitions=main-2003130074 X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: mahesh@linux.vnet.ibm.com, npiggin@gmail.com Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" MCE handling on pSeries platform fails as recent rework to use common code for pSeries and PowerNV in machine check error handling tries to access per-cpu variables in realmode. The per-cpu variables may be outside the RMO region on pSeries platform and needs translation to be enabled for access. Just moving these per-cpu variable into RMO region did'nt help because we queue some work to workqueues in real mode, which again tries to touch per-cpu variables. Also fwnmi_release_errinfo() cannot be called when translation is not enabled. This patch fixes this by enabling translation in the exception handler when all required real mode handling is done. This change only affects the pSeries platform. Without this fix below kernel crash is seen on injecting SLB multihit: BUG: Unable to handle kernel data access on read at 0xc00000027b205950 Faulting instruction address: 0xc00000000003b7e0 Oops: Kernel access of bad area, sig: 11 [#1] LE PAGE_SIZE=64K MMU=Hash SMP NR_CPUS=2048 NUMA pSeries Modules linked in: mcetest_slb(OE+) af_packet(E) xt_tcpudp(E) ip6t_rpfilter(E) ip6t_REJECT(E) ipt_REJECT(E) xt_conntrack(E) ip_set(E) nfnetlink(E) ebtable_nat(E) ebtable_broute(E) ip6table_nat(E) ip6table_mangle(E) ip6table_raw(E) ip6table_security(E) iptable_nat(E) nf_nat(E) nf_conntrack(E) nf_defrag_ipv6(E) nf_defrag_ipv4(E) iptable_mangle(E) iptable_raw(E) iptable_security(E) ebtable_filter(E) ebtables(E) ip6table_filter(E) ip6_tables(E) iptable_filter(E) ip_tables(E) x_tables(E) xfs(E) ibmveth(E) vmx_crypto(E) gf128mul(E) uio_pdrv_genirq(E) uio(E) crct10dif_vpmsum(E) rtc_generic(E) btrfs(E) libcrc32c(E) xor(E) zstd_decompress(E) zstd_compress(E) raid6_pq(E) sr_mod(E) sd_mod(E) cdrom(E) ibmvscsi(E) scsi_transport_srp(E) crc32c_vpmsum(E) dm_mod(E) sg(E) scsi_mod(E) CPU: 34 PID: 8154 Comm: insmod Kdump: loaded Tainted: G OE 5.5.0-mahesh #1 NIP: c00000000003b7e0 LR: c0000000000f2218 CTR: 0000000000000000 REGS: c000000007dcb960 TRAP: 0300 Tainted: G OE (5.5.0-mahesh) MSR: 8000000000001003 CR: 28002428 XER: 20040000 CFAR: c0000000000f2214 DAR: c00000027b205950 DSISR: 40000000 IRQMASK: 0 GPR00: c0000000000f2218 c000000007dcbbf0 c000000001544800 c000000007dcbd70 GPR04: 0000000000000001 c000000007dcbc98 c008000000d00258 c0080000011c0000 GPR08: 0000000000000000 0000000300000003 c000000001035950 0000000003000048 GPR12: 000000027a1d0000 c000000007f9c000 0000000000000558 0000000000000000 GPR16: 0000000000000540 c008000001110000 c008000001110540 0000000000000000 GPR20: c00000000022af10 c00000025480fd70 c008000001280000 c00000004bfbb300 GPR24: c000000001442330 c00800000800000d c008000008000000 4009287a77000510 GPR28: 0000000000000000 0000000000000002 c000000001033d30 0000000000000001 NIP [c00000000003b7e0] save_mce_event+0x30/0x240 LR [c0000000000f2218] pseries_machine_check_realmode+0x2c8/0x4f0 Call Trace: Instruction dump: 3c4c0151 38429050 7c0802a6 60000000 fbc1fff0 fbe1fff8 f821ffd1 3d42ffaf 3fc2ffaf e98d0030 394a1150 3bdef530 <7d6a62aa> 1d2b0048 2f8b0063 380b0001 ---[ end trace 46fd63f36bbdd940 ]--- Fixes: 9ca766f9891d ("powerpc/64s/pseries: machine check convert to use common event code") Signed-off-by: Ganesh Goudar --- arch/powerpc/kernel/exceptions-64s.S | 12 ++++++++++++ arch/powerpc/platforms/pseries/pseries.h | 1 + arch/powerpc/platforms/pseries/ras.c | 11 +++++++++++ 3 files changed, 24 insertions(+) diff --git a/arch/powerpc/kernel/exceptions-64s.S b/arch/powerpc/kernel/exceptions-64s.S index ffc15f4f079d..93d0fddd8074 100644 --- a/arch/powerpc/kernel/exceptions-64s.S +++ b/arch/powerpc/kernel/exceptions-64s.S @@ -2405,3 +2405,15 @@ replay_interrupt_return: blr _ASM_NOKPROBE_SYMBOL(__replay_interrupt) + +_GLOBAL(switch_to_virt_mode) + mflr r10 + mfmsr r11 + ori r11,r11,MSR_IR|MSR_DR + /* Clear MSR_RI before setting SRR0 and SRR1 */ + li r12,0 + mtmsrd r12,1 + mtspr SPRN_SRR0,r10 + mtspr SPRN_SRR1,r11 + RFI_TO_KERNEL + b . diff --git a/arch/powerpc/platforms/pseries/pseries.h b/arch/powerpc/platforms/pseries/pseries.h index 13fa370a87e4..768e3e0f137d 100644 --- a/arch/powerpc/platforms/pseries/pseries.h +++ b/arch/powerpc/platforms/pseries/pseries.h @@ -113,5 +113,6 @@ int dlpar_workqueue_init(void); void pseries_setup_rfi_flush(void); void pseries_lpar_read_hblkrm_characteristics(void); +extern void switch_to_virt_mode(void); #endif /* _PSERIES_PSERIES_H */ diff --git a/arch/powerpc/platforms/pseries/ras.c b/arch/powerpc/platforms/pseries/ras.c index 1d7f973c647b..5d49d9d711da 100644 --- a/arch/powerpc/platforms/pseries/ras.c +++ b/arch/powerpc/platforms/pseries/ras.c @@ -683,6 +683,17 @@ static int mce_handle_error(struct pt_regs *regs, struct rtas_error_log *errp) #endif out: + /* + * Enable translation as we will be accessing per-cpu variables + * in save_mce_event() which may fall outside RMO region, also + * leave it enabled because subsequently we will be queuing work + * to workqueues where again per-cpu variables accessed, besides + * fwnmi_release_errinfo() crashes when called in realmode on + * pseries. + * Note: All the realmode handling like flushing SLB entries for + * SLB multihit is done by now. + */ + switch_to_virt_mode(); save_mce_event(regs, disposition == RTAS_DISP_FULLY_RECOVERED, &mce_err, regs->nip, eaddr, paddr); -- 2.17.2