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=-9.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,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 2B2F4C282CE for ; Mon, 11 Feb 2019 15:56:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E093421B18 for ; Mon, 11 Feb 2019 15:56:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1549900611; bh=PMjMsMqB/V9zJCPlX2kWtTrDJ1KrGRYad9kcHa7PLz8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=SsSUzqFGTXkkZzDzIx1c2w23xTrV4YOj9xLoVSvRDM+3ya9T0UFN9Z8UKZ8iTKvPD vPIwAP0gFWnyAApl3dTO+yGvCGdqL5RNk3+1bhU9SzW3X4PUKPRX0Gcq7luq95CJJH qSbxL8tbYnQr075cnskUtai7GQo+1On92A4cKEwE= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731138AbfBKP4t (ORCPT ); Mon, 11 Feb 2019 10:56:49 -0500 Received: from mail.kernel.org ([198.145.29.99]:42190 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730486AbfBKOeE (ORCPT ); Mon, 11 Feb 2019 09:34:04 -0500 Received: from localhost (5356596B.cm-6-7b.dynamic.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 6E2BE206B7; Mon, 11 Feb 2019 14:34:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1549895643; bh=PMjMsMqB/V9zJCPlX2kWtTrDJ1KrGRYad9kcHa7PLz8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=V4/rW+xJDn3XdrjXjb49OlYmOLfzKG1obVa+3/5/vt0dZkTE99Y2AhYBSG8UqN6T1 YPQTiXB9ML2KqYrEXkYb/71sOw5cYWK+bcsG38sNEud1oUD+g2xJO/GGvVIxdGQ0H3 lcVJxPl3Ylm3DoBiDY4HtauSZ8sTMAMiCehDugQg= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, Finn Thain , Jens Axboe , Sasha Levin , Stan Johnson Subject: [PATCH 4.20 273/352] block/swim3: Fix -EBUSY error when re-opening device after unmount Date: Mon, 11 Feb 2019 15:18:20 +0100 Message-Id: <20190211141904.347218860@linuxfoundation.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190211141846.543045703@linuxfoundation.org> References: <20190211141846.543045703@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review X-Patchwork-Hint: ignore MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.20-stable review patch. If anyone has any objections, please let me know. ------------------ [ Upstream commit 296dcc40f2f2e402facf7cd26cf3f2c8f4b17d47 ] 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: Sasha Levin --- drivers/block/swim3.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/drivers/block/swim3.c b/drivers/block/swim3.c index c1c676a33e4a..3f6df3f1f5d9 100644 --- a/drivers/block/swim3.c +++ b/drivers/block/swim3.c @@ -995,7 +995,11 @@ static void floppy_release(struct gendisk *disk, fmode_t mode) 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); -- 2.19.1