From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S941343AbcHJTXX (ORCPT ); Wed, 10 Aug 2016 15:23:23 -0400 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:2603 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S941218AbcHJTXT (ORCPT ); Wed, 10 Aug 2016 15:23:19 -0400 X-IBM-Helo: d06dlp02.portsmouth.uk.ibm.com X-IBM-MailFrom: cornelia.huck@de.ibm.com X-IBM-RcptTo: linux-kernel@vger.kernel.org;netdev@vger.kernel.org Date: Wed, 10 Aug 2016 18:40:32 +0200 From: Cornelia Huck To: Jason Wang Cc: "David S. Miller" , netdev@vger.kernel.org, linux-kernel@vger.kernel.org, Christian Borntraeger Subject: [REGRESSION] 362899b ("macvtap: switch to use skb array") causes oops during teardown Organization: IBM Deutschland Research & Development GmbH Vorsitzende des Aufsichtsrats: Martina Koederitz =?UTF-8?B?R2VzY2jDpGZ0c2bDvGhydW5nOg==?= Dirk Wittkopp Sitz der Gesellschaft: =?UTF-8?B?QsO2Ymxpbmdlbg==?= Registergericht: Amtsgericht Stuttgart, HRB 243294 X-Mailer: Claws Mail 3.11.1 (GTK+ 2.24.23; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-TM-AS-MML: disable X-Content-Scanned: Fidelis XPS MAILER x-cbid: 16081016-0020-0000-0000-000001E617B6 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 16081016-0021-0000-0000-00001D111E78 Message-Id: <20160810184032.51f5429e.cornelia.huck@de.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:,, definitions=2016-08-10_13:,, signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 spamscore=0 suspectscore=2 malwarescore=0 phishscore=0 adultscore=0 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1604210000 definitions=main-1608100173 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org I'm hitting the following oops during shutdown (halt command in guest) of a libvirt-managed qemu guest 100% of the time: [ 108.920486] Unable to handle kernel pointer dereference in virtual kernel address space [ 108.920492] Failing address: 6b6b6b6b6b6b6000 TEID: 6b6b6b6b6b6b6803 [ 108.920495] Fault in home space mode while using kernel ASCE. [ 108.920504] AS:0000000000e20007 R3:0000000000000024 [ 108.920588] Oops: 0038 ilc:2 [#1] PREEMPT SMP [ 108.920592] Modules linked in: nf_conntrack_ipv4 nf_defrag_ipv4 xt_conntrack nf_conntrack ipt_REJECT nf_reject_ipv4 xt_tcpudp iptable_filter ip_tables x_tables bridge stp llc ghash_s390 prng ecb aes_s390 des_s390 des_generic sha512_s390 sha256_s390 sha1_s390 sha_common lockd grace vhost_net tun vhost macvtap macvlan kvm sunrpc dm_multipath dm_mod autofs4 [ 108.920628] CPU: 8 PID: 2648 Comm: qemu-system-s39 Not tainted 4.8.0-rc1-00031-gd3d312e #25 [ 108.920630] Hardware name: IBM 2964 NC9 704 (LPAR) [ 108.920634] Krnl PSW : 0704e00180000000 000000000064a3e8 (kfree_skb+0x38/0x288) [ 108.920640] R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:3 CC:2 PM:0 RI:0 EA:3 Krnl GPRS: 000000009fb04a5f 00000007a7a37d48 6b6b6b6b6b6b6b6b 000003ff80721af0 [ 108.920645] 000000000078d626 00000007a7a34000 0000000000000000 0000000000000008 [ 108.920647] 00000007b0f04210 00000007bde65718 000003ff80721afa 6b6b6b6b6b6b6b6b [ 108.920648] 00000007bde65698 0000000000807180 000003ff80721afa 00000007a7a37d08 [ 108.920656] Krnl Code: 000000000064a3da: b90400ae lgr %r10,%r14 000000000064a3de: b90400b2 lgr %r11,%r2 #000000000064a3e2: ec280121007c cgij %r2,0,8,64a624 >000000000064a3e8: 581020e4 l %r1,228(%r2) 000000000064a3ec: ec160005017e cij %r1,1,6,64a3f6 000000000064a3f2: a7f4000b brc 15,64a408 000000000064a3f6: a718ffff lhi %r1,-1 000000000064a3fa: eb1120e400f8 laa %r1,%r1,228(%r2) [ 108.920673] Call Trace: [ 108.920675] ([<00000007a7a37d28>] 0x7a7a37d28) [ 108.920679] ([<000003ff80721afa>] macvtap_sock_destruct+0x92/0xa8 [macvtap]) [ 108.920681] ([<0000000000647026>] __sk_destruct+0x3e/0x1f0) [ 108.920684] ([<000003ff80723ed8>] macvtap_release+0x150/0x1b0 [macvtap]) [ 108.920688] ([<000000000031bd72>] __fput+0x132/0x230) [ 108.920691] ([<000000000015f7aa>] task_work_run+0xb2/0xe8) [ 108.920695] ([<000000000078e494>] system_call+0xdc/0x270) [ 108.920697] INFO: lockdep is turned off. [ 108.920698] Last Breaking-Event-Address: [ 108.920700] [<000003ff80721100>] 0x3ff80721100 [ 108.920703] Kernel panic - not syncing: Fatal exception: panic_on_oops s390 host with a qeth device as the sole networking interface, one network interface in the guest, using vhost (I can try to figure out what libvirt is doing, if needed). If I revert 362899b ("macvtap: switch to use skb array") and its companion patch 0d7eacb ("macvtap: correctly free skb during socket destruction"), starting a guest via libvirt and halting it again from the guest works 100% of the time again. I'm willing to collect debug info if you tell me what you need.