From patchwork Wed Oct 4 08:28:56 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hannes Reinecke X-Patchwork-Id: 9983987 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id CE1A460365 for ; Wed, 4 Oct 2017 08:29:05 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id BF74D212DB for ; Wed, 4 Oct 2017 08:29:05 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id B2BB922B1F; Wed, 4 Oct 2017 08:29:05 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 37937212DB for ; Wed, 4 Oct 2017 08:29:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751875AbdJDI3C (ORCPT ); Wed, 4 Oct 2017 04:29:02 -0400 Received: from mx2.suse.de ([195.135.220.15]:56520 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751819AbdJDI27 (ORCPT ); Wed, 4 Oct 2017 04:28:59 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay1.suse.de (charybdis-ext.suse.de [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id 41216AC05; Wed, 4 Oct 2017 08:28:58 +0000 (UTC) From: Hannes Reinecke To: "Martin K. Petersen" Cc: Christoph Hellwig , James Bottomley , linux-scsi@vger.kernel.org, Hannes Reinecke , Hannes Reinecke Subject: [PATCH] scsi: fixup kernel warning during rmmod() Date: Wed, 4 Oct 2017 10:28:56 +0200 Message-Id: <1507105736-19148-1-git-send-email-hare@suse.de> X-Mailer: git-send-email 1.8.5.6 Sender: linux-scsi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Calling rmmod() on a FC driver will results in warnings like WARNING: CPU: 60 PID: 14640 at fs/sysfs/group.c:237 device_del+0x54/0x240() sysfs group ffffffff81eff140 not found for kobject '3:0:0:3' The problem here is that during scsi_remove_target() we will iterate over all devices, but fail to remove any of those as the call to scsi_device_get() fails the check to module_is_live(). Hence the devices will not be removed at this point, but all intermediate structures like fc rport etc. will be. Later on during scsi_forget_host() the devices are removed for real, but the device parent is already removed and causes this warning. Signed-off-by: Hannes Reinecke Reviewed-by: Johannes Thumshirn Reviewed-by: Kyle Fortin Tested-by: Don Brace --- drivers/scsi/scsi_sysfs.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) diff --git a/drivers/scsi/scsi_sysfs.c b/drivers/scsi/scsi_sysfs.c index 1889761..995539f 100644 --- a/drivers/scsi/scsi_sysfs.c +++ b/drivers/scsi/scsi_sysfs.c @@ -1336,13 +1336,19 @@ static void __scsi_remove_target(struct scsi_target *starget) spin_lock_irqsave(shost->host_lock, flags); restart: list_for_each_entry(sdev, &shost->__devices, siblings) { + /* + * We cannot call scsi_device_get() here, as + * we might've been called from rmmod() causing + * scsi_device_get() to fail the module_is_live() + * check. + */ if (sdev->channel != starget->channel || sdev->id != starget->id || - scsi_device_get(sdev)) + !get_device(&sdev->sdev_gendev)) continue; spin_unlock_irqrestore(shost->host_lock, flags); scsi_remove_device(sdev); - scsi_device_put(sdev); + put_device(&sdev->sdev_gendev); spin_lock_irqsave(shost->host_lock, flags); goto restart; }