From patchwork Tue Nov 16 11:20:32 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Tudor Ambarus X-Patchwork-Id: 12622049 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8B62FC433F5 for ; Tue, 16 Nov 2021 11:22:21 +0000 (UTC) Received: from vger.kernel.org (unknown [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 45EDA61055 for ; Tue, 16 Nov 2021 11:22:21 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 45EDA61055 Authentication-Results: mail.kernel.org; dmarc=fail (p=quarantine dis=none) header.from=microchip.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235027AbhKPLYy (ORCPT ); Tue, 16 Nov 2021 06:24:54 -0500 Received: from esa.microchip.iphmx.com ([68.232.153.233]:8906 "EHLO esa.microchip.iphmx.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234879AbhKPLYZ (ORCPT ); Tue, 16 Nov 2021 06:24:25 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=microchip.com; i=@microchip.com; q=dns/txt; s=mchp; t=1637061688; x=1668597688; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=K/FEmA4LkPsJngFC8rtp+wxmQUsyLjyVWQASV+7XuoM=; b=XUOEgZnN3uyBQmGHA5g0Ie0z5DXFuSqVfEcPAoCAEBsGswjp8e++zrKf BLyJwTW1lrxZlUJLQAbN8vO61P9OaSUxDfD/hSyXq4TAmszkbsh+CdraM cKHGGj5qbQ4TnHmD73mWpKh32ncgyqCeIaSzvb7Vl3opHc4hjwxxhw5vA qC/Q21ammK4wlVlYQTua4O4Kxvc8/OhAP4NevUbZdNVusaRarmEfMdTUr 9ov5/gU4t043auwCEehX0GNVjwmJgEOvv0mJWcDGyLLbM5swRefES+eX8 0ip5xI37NZgcqvlE1y2Kp67acQTeBGNrmtx22vaS0+uI5D8AT73kOQiiP w==; IronPort-SDR: 5I2Vtcxo1XNNrl5JKRV9Iz2lWjTf+jEudImraPfg9kfTsmk9Gq7BpbHvQWy8Z76ZizoLZC3vZg BTGwli5YolnlP5P8j2XexhEXs6jh126hdPMjF/YfFzSBYv7O9/IYKm8QZhheb2mNtSo7qIzepI uGgKLlma30lWyEE+YiRlCY3Aj7rc0Z0V17CK3GDQBzM2niE0PCJkK6kq75eTlQsZo7rLEh8ZOI /Gr8YAacR+NXlJAbFzulHwa1LeroQuar2AXH6L9I4Bsy/tOMAubQSpE+HRiHi9X8q8NKuKtoNt R8xnXSG44ai+VvlgIeZKpKym X-IronPort-AV: E=Sophos;i="5.87,239,1631602800"; d="scan'208";a="144082911" Received: from smtpout.microchip.com (HELO email.microchip.com) ([198.175.253.82]) by esa3.microchip.iphmx.com with ESMTP/TLS/AES256-SHA256; 16 Nov 2021 04:21:14 -0700 Received: from chn-vm-ex04.mchp-main.com (10.10.85.152) by chn-vm-ex01.mchp-main.com (10.10.85.143) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2176.14; Tue, 16 Nov 2021 04:21:14 -0700 Received: from ROB-ULT-M18064N.mchp-main.com (10.10.115.15) by chn-vm-ex04.mchp-main.com (10.10.85.152) with Microsoft SMTP Server id 15.1.2176.14 via Frontend Transport; Tue, 16 Nov 2021 04:21:11 -0700 From: Tudor Ambarus To: , , , , CC: , , , , , , , Tudor Ambarus Subject: [PATCH 09/13] dmaengine: at_xdmac: Fix concurrency over xfers_list Date: Tue, 16 Nov 2021 13:20:32 +0200 Message-ID: <20211116112036.96349-10-tudor.ambarus@microchip.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20211116112036.96349-1-tudor.ambarus@microchip.com> References: <20211116112036.96349-1-tudor.ambarus@microchip.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: dmaengine@vger.kernel.org Since tx_submit can be called from a hard irq, xfers_list must be protected with a lock to avoid concurency on the list's elements. Fixes: e1f7c9eee707 ("dmaengine: at_xdmac: creation of the atmel eXtended DMA Controller driver") Signed-off-by: Tudor Ambarus --- drivers/dma/at_xdmac.c | 17 ++++++++++------- 1 file changed, 10 insertions(+), 7 deletions(-) diff --git a/drivers/dma/at_xdmac.c b/drivers/dma/at_xdmac.c index 8804a86a9bcc..81f6f1357dcb 100644 --- a/drivers/dma/at_xdmac.c +++ b/drivers/dma/at_xdmac.c @@ -1608,14 +1608,17 @@ static void at_xdmac_handle_cyclic(struct at_xdmac_chan *atchan) struct at_xdmac_desc *desc; struct dma_async_tx_descriptor *txd; - if (!list_empty(&atchan->xfers_list)) { - desc = list_first_entry(&atchan->xfers_list, - struct at_xdmac_desc, xfer_node); - txd = &desc->tx_dma_desc; - - if (txd->flags & DMA_PREP_INTERRUPT) - dmaengine_desc_get_callback_invoke(txd, NULL); + spin_lock_irq(&atchan->lock); + if (list_empty(&atchan->xfers_list)) { + spin_unlock_irq(&atchan->lock); + return; } + desc = list_first_entry(&atchan->xfers_list, struct at_xdmac_desc, + xfer_node); + spin_unlock_irq(&atchan->lock); + txd = &desc->tx_dma_desc; + if (txd->flags & DMA_PREP_INTERRUPT) + dmaengine_desc_get_callback_invoke(txd, NULL); } static void at_xdmac_handle_error(struct at_xdmac_chan *atchan)