From patchwork Thu Sep 16 15:56:43 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg Kroah-Hartman X-Patchwork-Id: 513799 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=-19.1 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=ham 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 8AC1FC433F5 for ; Thu, 16 Sep 2021 17:08:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 77E5060F38 for ; Thu, 16 Sep 2021 17:08:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1344770AbhIPRKL (ORCPT ); Thu, 16 Sep 2021 13:10:11 -0400 Received: from mail.kernel.org ([198.145.29.99]:37566 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1349989AbhIPRIE (ORCPT ); Thu, 16 Sep 2021 13:08:04 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 4F30060F38; Thu, 16 Sep 2021 16:36:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1631810205; bh=ke0zryOFbY9VnDCnVu4dALHrZgEv3Vwhl3ONBxNtgdE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=eoBkMo97vJ4iYeqNNAdvbroHl7qbk4+ieoKOtoygjF6h2hkHXdSYO0ArG8a1Q66/9 ak6WCbiuadeYfiYesx7MlB0nX+oWvaq+YBmU9byBjHx6cVnD6cr8hjiGlH7e24FNYB PGzdfQ84l8fLcMVUsV1yvSubM8t1Ij6kj6Fus8Vk= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Julian Wiedmann , Benjamin Block , Heiko Carstens Subject: [PATCH 5.14 054/432] s390/qdio: fix roll-back after timeout on ESTABLISH ccw Date: Thu, 16 Sep 2021 17:56:43 +0200 Message-Id: <20210916155812.629973081@linuxfoundation.org> X-Mailer: git-send-email 2.33.0 In-Reply-To: <20210916155810.813340753@linuxfoundation.org> References: <20210916155810.813340753@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Julian Wiedmann commit 2c197870e4701610ec3b1143808d4e31152caf30 upstream. When qdio_establish() times out while waiting for the ESTABLISH ccw to complete, it calls qdio_shutdown() to roll back all of its previous actions. But at this point the qdio_irq's state is still QDIO_IRQ_STATE_INACTIVE, so qdio_shutdown() will exit immediately without doing any actual work. Which means that eg. the qdio_irq's thinint-indicator stays registered, and cdev->handler isn't restored to its old value. And since commit 954d6235be41 ("s390/qdio: make thinint registration symmetric") the qdio_irq also stays on the tiq_list, so on the next qdio_establish() we might get a helpful BUG from the list-debugging code: ... [ 4633.512591] list_add double add: new=00000000005a4110, prev=00000001b357db78, next=00000000005a4110. [ 4633.512621] ------------[ cut here ]------------ [ 4633.512623] kernel BUG at lib/list_debug.c:29! ... [ 4633.512796] [<00000001b2c6ee9a>] __list_add_valid+0x82/0xa0 [ 4633.512798] ([<00000001b2c6ee96>] __list_add_valid+0x7e/0xa0) [ 4633.512800] [<00000001b2fcecce>] qdio_establish_thinint+0x116/0x190 [ 4633.512805] [<00000001b2fcbe58>] qdio_establish+0x128/0x498 ... Fix this by extracting a goto-chain from the existing error exits in qdio_establish(), and check the return value of the wait_event_...() to detect the timeout condition. Fixes: 779e6e1c724d ("[S390] qdio: new qdio driver.") Root-caused-by: Benjamin Block Signed-off-by: Julian Wiedmann Reviewed-by: Benjamin Block Cc: # 2.6.27 Signed-off-by: Heiko Carstens Signed-off-by: Greg Kroah-Hartman --- drivers/s390/cio/qdio_main.c | 31 +++++++++++++++++++------------ 1 file changed, 19 insertions(+), 12 deletions(-) --- a/drivers/s390/cio/qdio_main.c +++ b/drivers/s390/cio/qdio_main.c @@ -1083,6 +1083,7 @@ int qdio_establish(struct ccw_device *cd { struct qdio_irq *irq_ptr = cdev->private->qdio_data; struct subchannel_id schid; + long timeout; int rc; ccw_device_get_schid(cdev, &schid); @@ -1111,11 +1112,8 @@ int qdio_establish(struct ccw_device *cd qdio_setup_irq(irq_ptr, init_data); rc = qdio_establish_thinint(irq_ptr); - if (rc) { - qdio_shutdown_irq(irq_ptr); - mutex_unlock(&irq_ptr->setup_mutex); - return rc; - } + if (rc) + goto err_thinint; /* establish q */ irq_ptr->ccw.cmd_code = irq_ptr->equeue.cmd; @@ -1131,15 +1129,16 @@ int qdio_establish(struct ccw_device *cd if (rc) { DBF_ERROR("%4x est IO ERR", irq_ptr->schid.sch_no); DBF_ERROR("rc:%4x", rc); - qdio_shutdown_thinint(irq_ptr); - qdio_shutdown_irq(irq_ptr); - mutex_unlock(&irq_ptr->setup_mutex); - return rc; + goto err_ccw_start; } - wait_event_interruptible_timeout(cdev->private->wait_q, - irq_ptr->state == QDIO_IRQ_STATE_ESTABLISHED || - irq_ptr->state == QDIO_IRQ_STATE_ERR, HZ); + timeout = wait_event_interruptible_timeout(cdev->private->wait_q, + irq_ptr->state == QDIO_IRQ_STATE_ESTABLISHED || + irq_ptr->state == QDIO_IRQ_STATE_ERR, HZ); + if (timeout <= 0) { + rc = (timeout == -ERESTARTSYS) ? -EINTR : -ETIME; + goto err_ccw_timeout; + } if (irq_ptr->state != QDIO_IRQ_STATE_ESTABLISHED) { mutex_unlock(&irq_ptr->setup_mutex); @@ -1156,6 +1155,14 @@ int qdio_establish(struct ccw_device *cd qdio_print_subchannel_info(irq_ptr); qdio_setup_debug_entries(irq_ptr); return 0; + +err_ccw_timeout: +err_ccw_start: + qdio_shutdown_thinint(irq_ptr); +err_thinint: + qdio_shutdown_irq(irq_ptr); + mutex_unlock(&irq_ptr->setup_mutex); + return rc; } EXPORT_SYMBOL_GPL(qdio_establish);