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=-9.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,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 4256EC3A5A6 for ; Thu, 19 Sep 2019 10:23:56 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (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 1874A21927 for ; Thu, 19 Sep 2019 10:23:56 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="GVzt9vMo" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 1874A21927 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=emlix.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-Id:Date:Subject:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=bcNjGxZO5lym1EZr6xKhcOTacGwzgDFD4rpGVh9dnL8=; b=GVzt9vMoKpHCZh OcTx2cSifa6axXSEq5WhrnRWKRzioFemJpTPeOXr7sU+3LoVAWF+I77SuMz7+Q/JkCFeVPqJBxHI/ USQE9gc4TE97pcJ41sWd1xHCatFtwdkr0vxVhg272xSZUVSYrV/883jpREitiadtUWFY1eoRLGMDF 1tJHPIYQ22AMLhmsal+aaesOow+Q5GmGLurIO31lE1EqT4QGZSpnyFNKWKrPIF8T349C09nGdzIyi 8i/dHjNhvyypw5VPvnXljvuh2BjBhxfSn926+elu6jti1k5yBCM8/pusHy8oyrLs3mcU9Vux9oVln NRv1hzd/hjceARPxAqsA==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92.2 #3 (Red Hat Linux)) id 1iAtbP-0000tY-KQ; Thu, 19 Sep 2019 10:23:55 +0000 Received: from mx1.emlix.com ([188.40.240.192]) by bombadil.infradead.org with esmtps (Exim 4.92.2 #3 (Red Hat Linux)) id 1iAtbB-0000ka-3B for linux-arm-kernel@lists.infradead.org; Thu, 19 Sep 2019 10:23:43 +0000 Received: from mailer.emlix.com (unknown [81.20.119.6]) (using TLSv1.2 with cipher ADH-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mx1.emlix.com (Postfix) with ESMTPS id C61E56038C; Thu, 19 Sep 2019 12:23:39 +0200 (CEST) From: Philipp Puschmann To: linux-kernel@vger.kernel.org Subject: [PATCH v2 1/3] dmaengine: imx-sdma: fix buffer ownership Date: Thu, 19 Sep 2019 12:23:17 +0200 Message-Id: <20190919102319.23368-2-philipp.puschmann@emlix.com> X-Mailer: git-send-email 2.23.0 In-Reply-To: <20190919102319.23368-1-philipp.puschmann@emlix.com> References: <20190911144943.21554-1-philipp.puschmann@emlix.com> <20190919102319.23368-1-philipp.puschmann@emlix.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190919_032341_868058_FEB158C2 X-CRM114-Status: GOOD ( 11.16 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: fugang.duan@nxp.com, Philipp Puschmann , festevam@gmail.com, s.hauer@pengutronix.de, vkoul@kernel.org, linux-imx@nxp.com, kernel@pengutronix.de, dan.j.williams@intel.com, yibin.gong@nxp.com, shawnguo@kernel.org, dmaengine@vger.kernel.or, linux-arm-kernel@lists.infradead.org, l.stach@pengutronix.de Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org BD_DONE flag marks ownership of the buffer. When 1 SDMA owns the buffer, when 0 ARM owns it. When processing the buffers in sdma_update_channel_loop the ownership of the currently processed buffer was set to SDMA again before running the callback function of the buffer and while the sdma script may be running in parallel. So there was the possibility to get the buffer overwritten by SDMA before it has been processed by kernel leading to kind of random errors in the upper layers, e.g. bluetooth. Signed-off-by: Philipp Puschmann --- Changelog v2: - add dma_wb() drivers/dma/imx-sdma.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/dma/imx-sdma.c b/drivers/dma/imx-sdma.c index 9ba74ab7e912..e029a2443cfc 100644 --- a/drivers/dma/imx-sdma.c +++ b/drivers/dma/imx-sdma.c @@ -802,7 +802,6 @@ static void sdma_update_channel_loop(struct sdma_channel *sdmac) */ desc->chn_real_count = bd->mode.count; - bd->mode.status |= BD_DONE; bd->mode.count = desc->period_len; desc->buf_ptail = desc->buf_tail; desc->buf_tail = (desc->buf_tail + 1) % desc->num_bd; @@ -817,6 +816,9 @@ static void sdma_update_channel_loop(struct sdma_channel *sdmac) dmaengine_desc_get_callback_invoke(&desc->vd.tx, NULL); spin_lock(&sdmac->vc.lock); + dma_wb(); + bd->mode.status |= BD_DONE; + if (error) sdmac->status = old_status; } -- 2.23.0 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel