Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933228AbdIXUmF (ORCPT ); Sun, 24 Sep 2017 16:42:05 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:60656 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933195AbdIXUl6 (ORCPT ); Sun, 24 Sep 2017 16:41:58 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Steffen Maier , Benjamin Block , "Martin K. Petersen" Subject: [PATCH 4.13 050/109] scsi: zfcp: fix queuecommand for scsi_eh commands when DIX enabled Date: Sun, 24 Sep 2017 22:33:11 +0200 Message-Id: <20170924203355.094338486@linuxfoundation.org> X-Mailer: git-send-email 2.14.1 In-Reply-To: <20170924203353.104695385@linuxfoundation.org> References: <20170924203353.104695385@linuxfoundation.org> User-Agent: quilt/0.65 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2483 Lines: 59 4.13-stable review patch. If anyone has any objections, please let me know. ------------------ From: Steffen Maier commit 71b8e45da51a7b64a23378221c0a5868bd79da4f upstream. Since commit db007fc5e20c ("[SCSI] Command protection operation"), scsi_eh_prep_cmnd() saves scmd->prot_op and temporarily resets it to SCSI_PROT_NORMAL. Other FCP LLDDs such as qla2xxx and lpfc shield their queuecommand() to only access any of scsi_prot_sg...() if (scsi_get_prot_op(cmd) != SCSI_PROT_NORMAL). Do the same thing for zfcp, which introduced DIX support with commit ef3eb71d8ba4 ("[SCSI] zfcp: Introduce experimental support for DIF/DIX"). Otherwise, TUR SCSI commands as part of scsi_eh likely fail in zfcp, because the regular SCSI command with DIX protection data, that scsi_eh re-uses in scsi_send_eh_cmnd(), of course still has (scsi_prot_sg_count() != 0) and so zfcp sends down bogus requests to the FCP channel hardware. This causes scsi_eh_test_devices() to have (finish_cmds == 0) [not SCSI device is online or not scsi_eh_tur() failed] so regular SCSI commands, that caused / were affected by scsi_eh, are moved to work_q and scsi_eh_test_devices() itself returns false. In turn, it unnecessarily escalates in our case in scsi_eh_ready_devs() beyond host reset to finally scsi_eh_offline_sdevs() which sets affected SCSI devices offline with the following kernel message: "kernel: sd H:0:T:L: Device offlined - not ready after error recovery" Signed-off-by: Steffen Maier Fixes: ef3eb71d8ba4 ("[SCSI] zfcp: Introduce experimental support for DIF/DIX") Reviewed-by: Benjamin Block Signed-off-by: Benjamin Block Signed-off-by: Martin K. Petersen Signed-off-by: Greg Kroah-Hartman --- drivers/s390/scsi/zfcp_fsf.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/drivers/s390/scsi/zfcp_fsf.c +++ b/drivers/s390/scsi/zfcp_fsf.c @@ -2258,7 +2258,8 @@ int zfcp_fsf_fcp_cmnd(struct scsi_cmnd * fcp_cmnd = (struct fcp_cmnd *) &req->qtcb->bottom.io.fcp_cmnd; zfcp_fc_scsi_to_fcp(fcp_cmnd, scsi_cmnd, 0); - if (scsi_prot_sg_count(scsi_cmnd)) { + if ((scsi_get_prot_op(scsi_cmnd) != SCSI_PROT_NORMAL) && + scsi_prot_sg_count(scsi_cmnd)) { zfcp_qdio_set_data_div(qdio, &req->qdio_req, scsi_prot_sg_count(scsi_cmnd)); retval = zfcp_qdio_sbals_from_sg(qdio, &req->qdio_req,