From patchwork Thu May 21 03:48:38 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kuninori Morimoto X-Patchwork-Id: 6452011 X-Patchwork-Delegate: geert@linux-m68k.org Return-Path: X-Original-To: patchwork-linux-sh@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 3768DC0432 for ; Thu, 21 May 2015 03:48:54 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 31169203B7 for ; Thu, 21 May 2015 03:48:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1504A203ED for ; Thu, 21 May 2015 03:48:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753713AbbEUDsu (ORCPT ); Wed, 20 May 2015 23:48:50 -0400 Received: from relmlor4.renesas.com ([210.160.252.174]:28733 "EHLO relmlie3.idc.renesas.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1753356AbbEUDst (ORCPT ); Wed, 20 May 2015 23:48:49 -0400 Received: from unknown (HELO relmlir3.idc.renesas.com) ([10.200.68.153]) by relmlie3.idc.renesas.com with ESMTP; 21 May 2015 12:48:48 +0900 Received: from relmlac3.idc.renesas.com (relmlac3.idc.renesas.com [10.200.69.23]) by relmlir3.idc.renesas.com (Postfix) with ESMTP id 1AA0843945; Thu, 21 May 2015 12:48:48 +0900 (JST) Received: by relmlac3.idc.renesas.com (Postfix, from userid 0) id 00CE51806F; Thu, 21 May 2015 12:48:47 +0900 (JST) Received: from relmlac3.idc.renesas.com (localhost [127.0.0.1]) by relmlac3.idc.renesas.com (Postfix) with ESMTP id EFAC81800A; Thu, 21 May 2015 12:48:47 +0900 (JST) Received: from relmlii1.idc.renesas.com [10.200.68.65] by relmlac3.idc.renesas.com with ESMTP id NBM03065; Thu, 21 May 2015 12:48:47 +0900 X-IronPort-AV: E=Sophos;i="5.13,466,1427727600"; d="scan'208";a="186648273" Received: from mail-hk1lp0117.outbound.protection.outlook.com (HELO APAC01-HK1-obe.outbound.protection.outlook.com) ([207.46.51.117]) by relmlii1.idc.renesas.com with ESMTP/TLS/AES256-SHA; 21 May 2015 12:48:46 +0900 Authentication-Results: spf=none (sender IP is ) smtp.mailfrom=kuninori.morimoto.gx@renesas.com; Received: from morimoto-PC.renesas.com (211.11.155.132) by SIXPR06MB318.apcprd06.prod.outlook.com (10.141.125.144) with Microsoft SMTP Server (TLS) id 15.1.166.22; Thu, 21 May 2015 03:48:38 +0000 Message-ID: <877fs2twwm.wl%kuninori.morimoto.gx@renesas.com> From: Kuninori Morimoto Subject: [PATCH 1/4 v2] dmaengine: rcar-dmac: fixup spinlock in rcar-dmac User-Agent: Wanderlust/2.15.9 Emacs/24.3 Mule/6.0 MIME-Version: 1.0 (generated by SEMI-EPG 1.14.7 - "Harue") To: Vinod Koul , Mark Brown CC: Simon , Nguyen Viet Dung , Magnus , Linux-SH , Linux-ALSA , Liam Girdwood , Laurent , Geert Uytterhoeven , Cao Minh Hiep , sakato , In-Reply-To: <878ucitwyh.wl%kuninori.morimoto.gx@renesas.com> References: <878ucitwyh.wl%kuninori.morimoto.gx@renesas.com> Date: Thu, 21 May 2015 03:48:38 +0000 X-Originating-IP: [211.11.155.132] X-ClientProxiedBy: OS1PR01CA0024.jpnprd01.prod.outlook.com (25.161.225.162) To SIXPR06MB318.apcprd06.prod.outlook.com (10.141.125.144) X-Microsoft-Antispam: UriScan:;BCL:0;PCL:0;RULEID:;SRVR:SIXPR06MB318; X-Microsoft-Antispam-PRVS: X-Exchange-Antispam-Report-Test: UriScan:; X-Exchange-Antispam-Report-CFA-Test: BCL:0; PCL:0; RULEID:(601004)(5005006)(3002001); SRVR:SIXPR06MB318; BCL:0; PCL:0; RULEID:; SRVR:SIXPR06MB318; X-Forefront-PRVS: 0583A86C08 X-Forefront-Antispam-Report: SFV:NSPM; SFS:(10019020)(6009001)(189002)(199003)(54356999)(76176999)(46406003)(69596002)(4001350100001)(19580405001)(50466002)(5001770100001)(77096005)(19580395003)(36756003)(50986999)(5001860100001)(5001830100001)(106356001)(5001960100002)(189998001)(87976001)(97736004)(2950100001)(68736005)(4001540100001)(81156007)(53416004)(62966003)(92566002)(42186005)(101416001)(105586002)(64706001)(23726002)(86362001)(77156002)(83506001)(47776003)(66066001)(122386002)(40100003)(33646002)(229853001)(46102003); DIR:OUT; SFP:1102; SCL:1; SRVR:SIXPR06MB318; H:morimoto-PC.renesas.com; FPR:; SPF:None; PTR:InfoNoRecords; MX:1; A:1; LANG:en; X-OriginatorOrg: renesas.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 21 May 2015 03:48:38.1505 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-Transport-CrossTenantHeadersStamped: SIXPR06MB318 Sender: linux-sh-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-sh@vger.kernel.org X-Spam-Status: No, score=-6.9 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, T_RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: Kuninori Morimoto Current rcar-dmac driver is using spin_lock_irq() / spin_unlock_irq() in some functions. But, some other driver might call DMAEngine API during interrupt disabled. In such case, rcar-dmac side spin_unlock_irq() forcefully allows all interrupts. Therefore, other driver receives unexpected interruption, and its exclusive access control will be broken. This patch replaces spin_lock_irq() to spin_lock_irqsave(), and spin_unlock_irq() to spin_unlock_irqrestore(). Reported-by: Cao Minh Hiep Signed-off-by: Kuninori Morimoto Tested-by: Keita Kobayashi Acked-by: Vinod Koul --- v1 -> v2 - .device_free_chan_resources() doesn't use spin_lock_irqsave() - rcar_dmac_isr_channel_thread() doesn't use spin_lock_irqsave() drivers/dma/sh/rcar-dmac.c | 37 +++++++++++++++++++++---------------- 1 file changed, 21 insertions(+), 16 deletions(-) diff --git a/drivers/dma/sh/rcar-dmac.c b/drivers/dma/sh/rcar-dmac.c index a18d16c..e0302c7 100644 --- a/drivers/dma/sh/rcar-dmac.c +++ b/drivers/dma/sh/rcar-dmac.c @@ -465,6 +465,7 @@ static dma_cookie_t rcar_dmac_tx_submit(struct dma_async_tx_descriptor *tx) static int rcar_dmac_desc_alloc(struct rcar_dmac_chan *chan, gfp_t gfp) { struct rcar_dmac_desc_page *page; + unsigned long flags; LIST_HEAD(list); unsigned int i; @@ -482,10 +483,10 @@ static int rcar_dmac_desc_alloc(struct rcar_dmac_chan *chan, gfp_t gfp) list_add_tail(&desc->node, &list); } - spin_lock_irq(&chan->lock); + spin_lock_irqsave(&chan->lock, flags); list_splice_tail(&list, &chan->desc.free); list_add_tail(&page->node, &chan->desc.pages); - spin_unlock_irq(&chan->lock); + spin_unlock_irqrestore(&chan->lock, flags); return 0; } @@ -516,6 +517,7 @@ static void rcar_dmac_desc_put(struct rcar_dmac_chan *chan, static void rcar_dmac_desc_recycle_acked(struct rcar_dmac_chan *chan) { struct rcar_dmac_desc *desc, *_desc; + unsigned long flags; LIST_HEAD(list); /* @@ -524,9 +526,9 @@ static void rcar_dmac_desc_recycle_acked(struct rcar_dmac_chan *chan) * list_for_each_entry_safe, isn't safe if we release the channel lock * around the rcar_dmac_desc_put() call. */ - spin_lock_irq(&chan->lock); + spin_lock_irqsave(&chan->lock, flags); list_splice_init(&chan->desc.wait, &list); - spin_unlock_irq(&chan->lock); + spin_unlock_irqrestore(&chan->lock, flags); list_for_each_entry_safe(desc, _desc, &list, node) { if (async_tx_test_ack(&desc->async_tx)) { @@ -539,9 +541,9 @@ static void rcar_dmac_desc_recycle_acked(struct rcar_dmac_chan *chan) return; /* Put the remaining descriptors back in the wait list. */ - spin_lock_irq(&chan->lock); + spin_lock_irqsave(&chan->lock, flags); list_splice(&list, &chan->desc.wait); - spin_unlock_irq(&chan->lock); + spin_unlock_irqrestore(&chan->lock, flags); } /* @@ -556,12 +558,13 @@ static void rcar_dmac_desc_recycle_acked(struct rcar_dmac_chan *chan) static struct rcar_dmac_desc *rcar_dmac_desc_get(struct rcar_dmac_chan *chan) { struct rcar_dmac_desc *desc; + unsigned long flags; int ret; /* Recycle acked descriptors before attempting allocation. */ rcar_dmac_desc_recycle_acked(chan); - spin_lock_irq(&chan->lock); + spin_lock_irqsave(&chan->lock, flags); while (list_empty(&chan->desc.free)) { /* @@ -570,17 +573,17 @@ static struct rcar_dmac_desc *rcar_dmac_desc_get(struct rcar_dmac_chan *chan) * allocated descriptors. If the allocation fails return an * error. */ - spin_unlock_irq(&chan->lock); + spin_unlock_irqrestore(&chan->lock, flags); ret = rcar_dmac_desc_alloc(chan, GFP_NOWAIT); if (ret < 0) return NULL; - spin_lock_irq(&chan->lock); + spin_lock_irqsave(&chan->lock, flags); } desc = list_first_entry(&chan->desc.free, struct rcar_dmac_desc, node); list_del(&desc->node); - spin_unlock_irq(&chan->lock); + spin_unlock_irqrestore(&chan->lock, flags); return desc; } @@ -593,6 +596,7 @@ static struct rcar_dmac_desc *rcar_dmac_desc_get(struct rcar_dmac_chan *chan) static int rcar_dmac_xfer_chunk_alloc(struct rcar_dmac_chan *chan, gfp_t gfp) { struct rcar_dmac_desc_page *page; + unsigned long flags; LIST_HEAD(list); unsigned int i; @@ -606,10 +610,10 @@ static int rcar_dmac_xfer_chunk_alloc(struct rcar_dmac_chan *chan, gfp_t gfp) list_add_tail(&chunk->node, &list); } - spin_lock_irq(&chan->lock); + spin_lock_irqsave(&chan->lock, flags); list_splice_tail(&list, &chan->desc.chunks_free); list_add_tail(&page->node, &chan->desc.pages); - spin_unlock_irq(&chan->lock); + spin_unlock_irqrestore(&chan->lock, flags); return 0; } @@ -627,9 +631,10 @@ static struct rcar_dmac_xfer_chunk * rcar_dmac_xfer_chunk_get(struct rcar_dmac_chan *chan) { struct rcar_dmac_xfer_chunk *chunk; + unsigned long flags; int ret; - spin_lock_irq(&chan->lock); + spin_lock_irqsave(&chan->lock, flags); while (list_empty(&chan->desc.chunks_free)) { /* @@ -638,18 +643,18 @@ rcar_dmac_xfer_chunk_get(struct rcar_dmac_chan *chan) * allocated descriptors. If the allocation fails return an * error. */ - spin_unlock_irq(&chan->lock); + spin_unlock_irqrestore(&chan->lock, flags); ret = rcar_dmac_xfer_chunk_alloc(chan, GFP_NOWAIT); if (ret < 0) return NULL; - spin_lock_irq(&chan->lock); + spin_lock_irqsave(&chan->lock, flags); } chunk = list_first_entry(&chan->desc.chunks_free, struct rcar_dmac_xfer_chunk, node); list_del(&chunk->node); - spin_unlock_irq(&chan->lock); + spin_unlock_irqrestore(&chan->lock, flags); return chunk; }