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=-3.7 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 BF868CA9EBD for ; Fri, 25 Oct 2019 18:11:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 94B2021E6F for ; Fri, 25 Oct 2019 18:11:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731688AbfJYSG5 (ORCPT ); Fri, 25 Oct 2019 14:06:57 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:46806 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731439AbfJYSFo (ORCPT ); Fri, 25 Oct 2019 14:05:44 -0400 Received: from [167.98.27.226] (helo=deadeye) by shadbolt.decadent.org.uk with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.89) (envelope-from ) id 1iO3xw-0008P4-W8; Fri, 25 Oct 2019 19:05:37 +0100 Received: from ben by deadeye with local (Exim 4.92.2) (envelope-from ) id 1iO3xw-0001k4-4F; Fri, 25 Oct 2019 19:05:36 +0100 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, Denis Kirjanov , "Vasily Gorbik" , "Julian Wiedmann" Date: Fri, 25 Oct 2019 19:03:33 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) X-Patchwork-Hint: ignore Subject: [PATCH 3.16 32/47] s390/qdio: don't touch the dsci in tiqdio_add_input_queues() In-Reply-To: X-SA-Exim-Connect-IP: 167.98.27.226 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org 3.16.76-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Julian Wiedmann commit ac6639cd3db607d386616487902b4cc1850a7be5 upstream. Current code sets the dsci to 0x00000080. Which doesn't make any sense, as the indicator area is located in the _left-most_ byte. Worse: if the dsci is the _shared_ indicator, this potentially clears the indication of activity for a _different_ device. tiqdio_thinint_handler() will then have no reason to call that device's IRQ handler, and the device ends up stalling. Fixes: d0c9d4a89fff ("[S390] qdio: set correct bit in dsci") Signed-off-by: Julian Wiedmann Signed-off-by: Vasily Gorbik Signed-off-by: Ben Hutchings --- drivers/s390/cio/qdio_thinint.c | 1 - 1 file changed, 1 deletion(-) --- a/drivers/s390/cio/qdio_thinint.c +++ b/drivers/s390/cio/qdio_thinint.c @@ -80,7 +80,6 @@ void tiqdio_add_input_queues(struct qdio mutex_lock(&tiq_list_lock); list_add_rcu(&irq_ptr->input_qs[0]->entry, &tiq_list); mutex_unlock(&tiq_list_lock); - xchg(irq_ptr->dsci, 1 << 7); } void tiqdio_remove_input_queues(struct qdio_irq *irq_ptr)