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=-4.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED 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 75043C4360F for ; Tue, 2 Apr 2019 13:48:21 +0000 (UTC) Received: from lists.ozlabs.org (lists.ozlabs.org [203.11.71.2]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id F274821473 for ; Tue, 2 Apr 2019 13:48:20 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org F274821473 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=decadent.org.uk Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Received: from lists.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 44YVsZ74knzDqN5 for ; Wed, 3 Apr 2019 00:48:18 +1100 (AEDT) Authentication-Results: lists.ozlabs.org; spf=pass (mailfrom) smtp.mailfrom=decadent.org.uk (client-ip=88.96.1.126; helo=shadbolt.e.decadent.org.uk; envelope-from=ben@decadent.org.uk; receiver=) Authentication-Results: lists.ozlabs.org; dmarc=none (p=none dis=none) header.from=decadent.org.uk Received: from shadbolt.e.decadent.org.uk (shadbolt.e.decadent.org.uk [88.96.1.126]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 44YVhL0Hs3zDqNZ for ; Wed, 3 Apr 2019 00:40:17 +1100 (AEDT) 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 1hBJe4-0002p6-4f; Tue, 02 Apr 2019 14:40:08 +0100 Received: from ben by deadeye with local (Exim 4.92) (envelope-from ) id 1hBJdy-0004xt-2s; Tue, 02 Apr 2019 14:40:02 +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 Date: Tue, 02 Apr 2019 14:38:28 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) X-Patchwork-Hint: ignore Subject: [PATCH 3.16 92/99] block/swim3: Fix -EBUSY error when re-opening device after unmount 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 X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Jens Axboe , akpm@linux-foundation.org, linuxppc-dev@lists.ozlabs.org, Denis Kirjanov , Finn Thain Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" 3.16.65-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Finn Thain commit 296dcc40f2f2e402facf7cd26cf3f2c8f4b17d47 upstream. When the block device is opened with FMODE_EXCL, ref_count is set to -1. This value doesn't get reset when the device is closed which means the device cannot be opened again. Fix this by checking for refcount <= 0 in the release method. Reported-and-tested-by: Stan Johnson Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Cc: linuxppc-dev@lists.ozlabs.org Signed-off-by: Finn Thain Signed-off-by: Jens Axboe Signed-off-by: Ben Hutchings --- drivers/block/swim3.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) --- a/drivers/block/swim3.c +++ b/drivers/block/swim3.c @@ -1027,7 +1027,11 @@ static void floppy_release(struct gendis struct swim3 __iomem *sw = fs->swim3; mutex_lock(&swim3_mutex); - if (fs->ref_count > 0 && --fs->ref_count == 0) { + if (fs->ref_count > 0) + --fs->ref_count; + else if (fs->ref_count == -1) + fs->ref_count = 0; + if (fs->ref_count == 0) { swim3_action(fs, MOTOR_OFF); out_8(&sw->control_bic, 0xff); swim3_select(fs, RELAX);