From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933134AbcGLDQq (ORCPT ); Mon, 11 Jul 2016 23:16:46 -0400 Received: from mail-qk0-f195.google.com ([209.85.220.195]:34784 "EHLO mail-qk0-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932496AbcGLDQo convert rfc822-to-8bit (ORCPT ); Mon, 11 Jul 2016 23:16:44 -0400 MIME-Version: 1.0 In-Reply-To: References: <20160711221544.42291-1-li.feng@oracle.com> From: Feng Li Date: Tue, 12 Jul 2016 11:16:13 +0800 Message-ID: Subject: Re: [PATCH] iscsi-target: fix panic when add the second TCP connection to iSCSI session To: nab@linux-iscsi.org, agrover@redhat.com, varun@chelsio.com, Herbert Xu , Roland Dreier , Zhu Lingshan Cc: linux-scsi@vger.kernel.org, target-devel@vger.kernel.org, linux-kernel , Feng Li , Sumit Rai Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Add lszhu@suse.com 2016-07-11 22:23 GMT+08:00 冯力 : > This problem exists at least from v3.16. > The upstream kernel still exists this issue. > > I have tested my patch and the following panic is disappeared. > > Thanks, > - Alex > > #dmesg > > [ 1160.788676] sd 16:0:0:0: [sde] Attached SCSI disk > [ 1383.962626] target_core_get_fabric() failed for usb_gadget > [ 1404.788910] TARGET_CORE[iSCSI]: Unsupported SCSI Opcode 0x1b, > sending CHECK_CONDITION. > [ 1404.858451] BUG: unable to handle kernel NULL pointer dereference > at 00000000000001f8 > [ 1404.858911] IP: [] > iscsi_target_login_thread+0x728/0x10b0 [iscsi_target_mod] > [ 1404.859746] PGD 230c29067 PUD 232060067 PMD 0 > [ 1404.859963] Oops: 0000 [#1] SMP > [ 1404.860154] Modules linked in: crc32c_generic tcm_loop tcm_qla2xxx > qla2xxx iscsi_target_mod ib_srpt vhost_scsi vhost tcm_fc libfc > scsi_transport_fc scsi_tgt target_core_file target_core_iblock > target_core_pscsi target_core_mod configfs nbd > vmw_vsock_vmci_transport vsock bridge stp llc vmhgfs(O) snd_ens1371 > snd_rawmidi snd_seq_device snd_ac97_codec snd_pcm snd_timer snd > vmw_balloon evdev soundcore ac97_bus gameport ppdev pcspkr sg psmouse > serio_raw parport_pc vmwgfx parport battery ttm drm_kms_helper drm > i2c_piix4 shpchp i2c_core vmw_vmci processor thermal_sys ac button > binfmt_misc md_mod ib_iser rdma_cm iw_cm ib_cm ib_sa ib_mad ib_core > ib_addr iscsi_tcp libiscsi_tcp libiscsi scsi_transport_iscsi > hid_generic usbhid hid ext4 crc16 mbcache jbd2 sd_mod crc_t10dif > crct10dif_generic crct10dif_common ata_generic > [ 1404.861278] mptspi scsi_transport_spi mptscsih ata_piix uhci_hcd > ehci_pci ehci_hcd mptbase libata usbcore e1000 usb_common scsi_mod > sunrpc dm_mirror dm_region_hash dm_log dm_mod autofs4 > [ 1404.861742] CPU: 2 PID: 1865 Comm: iscsi_np Tainted: G O > 3.16.0-4-amd64 #1 Debian 3.16.7-ckt25-1 > [ 1404.861868] Hardware name: VMware, Inc. VMware Virtual > Platform/440BX Desktop Reference Platform, BIOS 6.00 07/02/2015 > [ 1404.862033] task: ffff880234c849a0 ti: ffff8800b9c20000 task.ti: > ffff8800b9c20000 > [ 1404.862114] RIP: 0010:[] [] > iscsi_target_login_thread+0x728/0x10b0 [iscsi_target_mod] > [ 1404.862233] RSP: 0018:ffff8800b9c23e60 EFLAGS: 00010246 > [ 1404.862282] RAX: 0000000000000000 RBX: ffff88023125b800 RCX: ffff8802b4d8d000 > [ 1404.862344] RDX: 000000000000002d RSI: 00000000fffffe01 RDI: ffff880233ef1800 > [ 1404.862406] RBP: ffff8800b9651a00 R08: 00000000d5a073de R09: ffff88023487e6c0 > [ 1404.862585] R10: 00000000ead0c2e5 R11: 00000000d039ef6a R12: ffff88023125b854 > [ 1404.865580] R13: ffff88023125b908 R14: ffff880233ef1800 R15: ffff880234c849a0 > [ 1404.867732] FS: 00007fba67e2fb80(0000) GS:ffff88023e640000(0000) > knlGS:0000000000000000 > [ 1404.869772] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b > [ 1404.871850] CR2: 00000000000001f8 CR3: 0000000230ffa000 CR4: 00000000000007e0 > [ 1404.874271] Stack: > [ 1404.877492] ffff88023125b908 00ff880234c849a0 ffff88023125b858 > ffff88023481f400 > [ 1404.880162] ffffffff81510d00 ffff880230768000 ffff8800b9c23fd8 > 0000000000012f00 > [ 1404.883545] ffff880234c849a0 ffff880233e9da40 ffff88023125b800 > ffffffffa05edeb0 > [ 1404.885865] Call Trace: > [ 1404.888384] [] ? __schedule+0x250/0x700 > [ 1404.890619] [] ? > iscsi_target_login_sess_out+0x240/0x240 [iscsi_target_mod] > [ 1404.892668] [] ? kthread+0xbd/0xe0 > [ 1404.894646] [] ? kthread_create_on_node+0x180/0x180 > [ 1404.896553] [] ? ret_from_fork+0x58/0x90 > [ 1404.898556] [] ? kthread_create_on_node+0x180/0x180 > [ 1404.900597] Code: 09 00 00 48 89 ea 4c 89 f6 48 89 df e8 52 1b 00 > 00 85 c0 0f 88 82 02 00 00 0f b6 44 24 0f 4c 89 f7 88 45 09 49 8b 86 > d8 04 00 00 <4c> 8b a8 f8 01 00 00 49 8b 86 a0 04 00 00 ff 90 98 00 00 > 00 41 > [ 1404.906962] RIP [] > iscsi_target_login_thread+0x728/0x10b0 [iscsi_target_mod] > [ 1404.908962] RSP > [ 1404.910940] CR2: 00000000000001f8 > [ 1404.917670] ---[ end trace d29d8c681ab2bdfb ]--- > [ 1419.859690] iSCSI Login timeout on Network Portal 10.182.70.69:3260 > [ 1479.832056] iSCSI Login timeout on Network Portal 10.182.70.68:3260 > [ 1479.835739] iSCSI Login negotiation failed. > [ 1549.332632] iSCSI Login timeout on Network Portal 10.182.70.68:3260 > [ 1549.338432] iSCSI Login negotiation failed. > [ 1564.358423] iSCSI Login timeout on Network Portal 10.182.70.68:3260 > [ 1564.362443] iSCSI Login negotiation failed. > > 2016-07-12 6:15 GMT+08:00 Feng Li : >> From: Feng Li >> >> In MC/S scenario, the conn->sess has been set NULL in >> iscsi_login_non_zero_tsih_s1 when the second connection comes here, >> then kernel panic. >> >> The conn->sess will be assigned in iscsi_login_non_zero_tsih_s2. So >> we should check whether it's NULL before calling. >> >> Signed-off-by: Feng Li >> --- >> drivers/target/iscsi/iscsi_target_login.c | 5 +++-- >> 1 file changed, 3 insertions(+), 2 deletions(-) >> >> diff --git a/drivers/target/iscsi/iscsi_target_login.c b/drivers/target/iscsi/iscsi_target_login.c >> index b5212f0..adf419f 100644 >> --- a/drivers/target/iscsi/iscsi_target_login.c >> +++ b/drivers/target/iscsi/iscsi_target_login.c >> @@ -1371,8 +1371,9 @@ static int __iscsi_target_login_thread(struct iscsi_np *np) >> } >> login->zero_tsih = zero_tsih; >> >> - conn->sess->se_sess->sup_prot_ops = >> - conn->conn_transport->iscsit_get_sup_prot_ops(conn); >> + if (conn->sess) >> + conn->sess->se_sess->sup_prot_ops = >> + conn->conn_transport->iscsit_get_sup_prot_ops(conn); >> >> tpg = conn->tpg; >> if (!tpg) { >> -- >> 2.9.0 >> > > > > -- > Thanks and Best Regards, > Feng Li(Alex) -- Thanks and Best Regards, Feng Li(Alex)