From patchwork Thu Sep 3 08:01:09 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christoph Hellwig X-Patchwork-Id: 296875 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=-12.8 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable 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 B04D9C433E7 for ; Thu, 3 Sep 2020 08:15:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 846FB2145D for ; Thu, 3 Sep 2020 08:15:15 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="KFoHKJIn" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728899AbgICIOs (ORCPT ); Thu, 3 Sep 2020 04:14:48 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60954 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728280AbgICIBj (ORCPT ); Thu, 3 Sep 2020 04:01:39 -0400 Received: from casper.infradead.org (casper.infradead.org [IPv6:2001:8b0:10b:1236::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 363B0C061245; Thu, 3 Sep 2020 01:01:39 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=Content-Transfer-Encoding:MIME-Version: References:In-Reply-To:Message-Id:Date:Subject:Cc:To:From:Sender:Reply-To: Content-Type:Content-ID:Content-Description; bh=jtS62lQ0Rm8mpaW0OdPDrzysFsFYBLY+VRU8MHAlSxE=; b=KFoHKJIntr7HYs+GfXiVXMrydl u16r7jFZuBANNgpX4jFo0Yd1h0BICAJwVVjJ1GGFBaiHgOXQToB7uwSp1c4rpnu55LfhHmnTUr/I3 96JMJCBua8BT/hsCfaMcf96vAkpcfCUxfCejuQN34FoZ8GPBNF3H1JwHmnAve95NtABOe9Elg1LPg OI0Uf51wlkU6xXig7Hb1qLBOl1DSov2nlLalbe0bl3z70gfDT9FVHradEDJ5Bx7ZrvMy6ur2ZxnuY 5jH1/ixX8IWNfBI9ICzHVPNAawlIBjbHJ00OkTyuxk5bhNQp0hd0rk7zCs9DCPTfRyrYtvHY+7aHx JLGPtaHw==; Received: from [2001:4bb8:184:af1:c70:4a89:bc61:2] (helo=localhost) by casper.infradead.org with esmtpsa (Exim 4.92.3 #3 (Red Hat Linux)) id 1kDkBZ-0006bg-L2; Thu, 03 Sep 2020 08:01:33 +0000 From: Christoph Hellwig To: Jens Axboe Cc: Greg Kroah-Hartman , "Rafael J. Wysocki" , Denis Efremov , "David S. Miller" , Song Liu , Al Viro , Finn Thain , Michael Schmitz , linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, linux-ide@vger.kernel.org, linux-raid@vger.kernel.org, linux-scsi@vger.kernel.org, linux-m68k@lists.linux-m68k.org Subject: [PATCH 09/19] sd: use __register_blkdev to avoid a modprobe for an unregistered dev_t Date: Thu, 3 Sep 2020 10:01:09 +0200 Message-Id: <20200903080119.441674-10-hch@lst.de> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20200903080119.441674-1-hch@lst.de> References: <20200903080119.441674-1-hch@lst.de> MIME-Version: 1.0 X-SRS-Rewrite: SMTP reverse-path rewritten from by casper.infradead.org. See http://www.infradead.org/rpr.html Sender: linux-scsi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org Switch from using blk_register_region to the probe callback passed to __register_blkdev to disable the request_module call for an unclaimed dev_t in the SD majors. Signed-off-by: Christoph Hellwig --- drivers/scsi/sd.c | 19 +++++-------------- 1 file changed, 5 insertions(+), 14 deletions(-) diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c index 2bec8cd526164d..97bf84b1871571 100644 --- a/drivers/scsi/sd.c +++ b/drivers/scsi/sd.c @@ -596,13 +596,11 @@ static struct scsi_driver sd_template = { }; /* - * Dummy kobj_map->probe function. - * The default ->probe function will call modprobe, which is - * pointless as this module is already loaded. + * Don't request a new module, as that could deadlock in multipath + * environment. */ -static struct kobject *sd_default_probe(dev_t devt, int *partno, void *data) +static void sd_default_probe(dev_t devt) { - return NULL; } /* @@ -3481,9 +3479,6 @@ static int sd_remove(struct device *dev) free_opal_dev(sdkp->opal_dev); - blk_register_region(devt, SD_MINORS, NULL, - sd_default_probe, NULL, NULL); - mutex_lock(&sd_ref_mutex); dev_set_drvdata(dev, NULL); put_device(&sdkp->dev); @@ -3673,11 +3668,9 @@ static int __init init_sd(void) SCSI_LOG_HLQUEUE(3, printk("init_sd: sd driver entry point\n")); for (i = 0; i < SD_MAJORS; i++) { - if (register_blkdev(sd_major(i), "sd") != 0) + if (__register_blkdev(sd_major(i), "sd", sd_default_probe)) continue; majors++; - blk_register_region(sd_major(i), SD_MINORS, NULL, - sd_default_probe, NULL, NULL); } if (!majors) @@ -3750,10 +3743,8 @@ static void __exit exit_sd(void) class_unregister(&sd_disk_class); - for (i = 0; i < SD_MAJORS; i++) { - blk_unregister_region(sd_major(i), SD_MINORS); + for (i = 0; i < SD_MAJORS; i++) unregister_blkdev(sd_major(i), "sd"); - } } module_init(init_sd);