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=-20.2 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, 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 B22A7C64E64 for ; Mon, 19 Jul 2021 15:57:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9F0AC61402 for ; Mon, 19 Jul 2021 15:57:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1347341AbhGSPP7 (ORCPT ); Mon, 19 Jul 2021 11:15:59 -0400 Received: from mail.kernel.org ([198.145.29.99]:40456 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1343642AbhGSOsb (ORCPT ); Mon, 19 Jul 2021 10:48:31 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id C32ED61205; Mon, 19 Jul 2021 15:24:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1626708259; bh=EACN06jeR+HmOakUjwaxQakXBayQUM2oTJ89JBlOwIE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Ysp4bP8VSjRQUmamNk4PRb2e5p0k/SzWBP8YMVE5i0bPd9tDRr33KO509+1UeHBfC Zxba1hEGkhJpDwdro6GPTWNZeNJsNmhh90S9/L00dP0MZfxfKQUfxzr9O2hHUv66VY Fs1lCAXuOaVC+xfgve7FupFKQjtaCC5fFU3pyWxs= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Ming Lei , Bart Van Assche , John Garry , "Martin K. Petersen" , Sasha Levin Subject: [PATCH 4.14 242/315] scsi: core: Cap scsi_host cmd_per_lun at can_queue Date: Mon, 19 Jul 2021 16:52:11 +0200 Message-Id: <20210719144951.377595343@linuxfoundation.org> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20210719144942.861561397@linuxfoundation.org> References: <20210719144942.861561397@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: John Garry [ Upstream commit ea2f0f77538c50739b9fb4de4700cee5535e1f77 ] The sysfs handling function sdev_store_queue_depth() enforces that the sdev queue depth cannot exceed shost can_queue. The initial sdev queue depth comes from shost cmd_per_lun. However, the LLDD may manually set cmd_per_lun to be larger than can_queue, which leads to an initial sdev queue depth greater than can_queue. Such an issue was reported in [0], which caused a hang. That has since been fixed in commit fc09acb7de31 ("scsi: scsi_debug: Fix cmd_per_lun, set to max_queue"). Stop this possibly happening for other drivers by capping shost cmd_per_lun at shost can_queue. [0] https://lore.kernel.org/linux-scsi/YHaez6iN2HHYxYOh@T590/ Link: https://lore.kernel.org/r/1621434662-173079-1-git-send-email-john.garry@huawei.com Reviewed-by: Ming Lei Reviewed-by: Bart Van Assche Signed-off-by: John Garry Signed-off-by: Martin K. Petersen Signed-off-by: Sasha Levin --- drivers/scsi/hosts.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/scsi/hosts.c b/drivers/scsi/hosts.c index 20bb5a7dca3c..ec976b93341c 100644 --- a/drivers/scsi/hosts.c +++ b/drivers/scsi/hosts.c @@ -213,6 +213,9 @@ int scsi_add_host_with_dma(struct Scsi_Host *shost, struct device *dev, goto fail; } + shost->cmd_per_lun = min_t(short, shost->cmd_per_lun, + shost->can_queue); + error = scsi_init_sense_cache(shost); if (error) goto fail; -- 2.30.2