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=-2.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=no 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 D43E3CA9EAF for ; Thu, 24 Oct 2019 09:50:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id AC3692166E for ; Thu, 24 Oct 2019 09:50:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2390231AbfJXJuf (ORCPT ); Thu, 24 Oct 2019 05:50:35 -0400 Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:52902 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725775AbfJXJuf (ORCPT ); Thu, 24 Oct 2019 05:50:35 -0400 Received: from pps.filterd (m0098409.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.27/8.16.0.27) with SMTP id x9O9lA0d130326 for ; Thu, 24 Oct 2019 05:50:33 -0400 Received: from e06smtp01.uk.ibm.com (e06smtp01.uk.ibm.com [195.75.94.97]) by mx0a-001b2d01.pphosted.com with ESMTP id 2vu6m5xy3c-1 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NOT) for ; Thu, 24 Oct 2019 05:50:32 -0400 Received: from localhost by e06smtp01.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) Thu, 24 Oct 2019 10:50:28 +0100 Received: from d06av26.portsmouth.uk.ibm.com (d06av26.portsmouth.uk.ibm.com [9.149.105.62]) by b06cxnps3075.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id x9O9oRHi62718028 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Thu, 24 Oct 2019 09:50:27 GMT Received: from d06av26.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 11779AE058; Thu, 24 Oct 2019 09:50:27 +0000 (GMT) Received: from d06av26.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id E59CEAE055; Thu, 24 Oct 2019 09:50:26 +0000 (GMT) Received: from oc4120165700.ibm.com (unknown [9.152.98.184]) by d06av26.portsmouth.uk.ibm.com (Postfix) with ESMTP; Thu, 24 Oct 2019 09:50:26 +0000 (GMT) Subject: Re: Query: SCSI Device node creation when UFS is loaded as a module To: asutoshd@codeaurora.org, linux-scsi@vger.kernel.org References: <468eb805fa69da76c88a0a37aa209c7f@codeaurora.org> From: Steffen Maier Date: Thu, 24 Oct 2019 11:50:26 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.9.0 MIME-Version: 1.0 In-Reply-To: <468eb805fa69da76c88a0a37aa209c7f@codeaurora.org> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit X-TM-AS-GCONF: 00 x-cbid: 19102409-4275-0000-0000-00000376C266 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 19102409-4276-0000-0000-00003889EC0E Message-Id: X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:,, definitions=2019-10-24_06:,, signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 malwarescore=0 suspectscore=0 phishscore=0 bulkscore=0 spamscore=0 clxscore=1015 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1908290000 definitions=main-1910240096 Sender: linux-scsi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org On 10/24/19 1:51 AM, asutoshd@codeaurora.org wrote: > Hi > I'm loading the ufs-qcom driver as a module but am not seeing the /dev/sda* > device nodes. > Looks like it's not being created. > > I find the sda nodes in other paths being enumerated though: > > / # find /sys -name sda > /sys/kernel/debug/block/sda > /sys/class/block/sda > /sys/devices/platform/<...>/.ufshc/host0/target0:0:0/0:0:0:0/block/sda > /sys/block/sda > > All Luns are detected and I see sda is detected and prints for all the Luns as > below -: > sd 0:0:0:0: [sda] .... ....-byte logical blocks: > > ... so on ... > > But if I link it statically instead of a module, it works fine. All device > nodes are created. > > I'm trying to figure out where/how in SCSI does it create these device nodes - > /dev/sd ? That's from (systemd-)udevd user space based on uevents from the kernel. > I've looked into sd.c but I couldn't figure out the exact place yet. Yeah, based on the SCSI device probe and add lun, the high level driver sd would emit udev events for block devices. -- Mit freundlichen Gruessen / Kind regards Steffen Maier Linux on IBM Z Development https://www.ibm.com/privacy/us/en/ IBM Deutschland Research & Development GmbH Vorsitzender des Aufsichtsrats: Matthias Hartmann Geschaeftsfuehrung: Dirk Wittkopp Sitz der Gesellschaft: Boeblingen Registergericht: Amtsgericht Stuttgart, HRB 243294