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 76C09C04E53 for ; Wed, 15 May 2019 11:38:31 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 342632053B for ; Wed, 15 May 2019 11:38:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1557920311; bh=MIhzsOA6fwEdEx1ikBp/ndqyYoZ40hTNplsc78QFuCU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=EUHEP9bhRedyp+ZlsJnJwo/AvEQ1HiFcKedVscyeHFqhaPkLP2M2HkqGe2bcw62yz JbQP2zwubMmPsdxjepjG5Ll0W9aNnmoztp4XROHvH0o67KOPUR1quj7Soz7oNnv/yJ p6QJeFQCDUksQTpmQk/Eg1Hopdaj+IcDsCURyutY= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732829AbfEOLbG (ORCPT ); Wed, 15 May 2019 07:31:06 -0400 Received: from mail.kernel.org ([198.145.29.99]:42772 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732840AbfEOLbG (ORCPT ); Wed, 15 May 2019 07:31:06 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.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 14C5E206BF; Wed, 15 May 2019 11:31:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1557919865; bh=MIhzsOA6fwEdEx1ikBp/ndqyYoZ40hTNplsc78QFuCU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=DC+AlT5gLvqmW58XL2bJ39yMqrYRv1LqmnnpWArOBJA6fIV81P5DjwpmDjcjmU5Gd 1RezUTSGj0SrbydDAJw/r+y7iG3wx4zGqNdtBBQiXf/YMcqAbBV4g3ucU9BvIAsvME bEhcx0cSpU2pol1Dq6vlCP46gTWbDp5VP3FFrOQs= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Aaro Koskinen , Stefan Wahren , Vinod Koul , Sasha Levin Subject: [PATCH 5.0 079/137] dmaengine: bcm2835: Avoid GFP_KERNEL in device_prep_slave_sg Date: Wed, 15 May 2019 12:56:00 +0200 Message-Id: <20190515090659.195406339@linuxfoundation.org> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190515090651.633556783@linuxfoundation.org> References: <20190515090651.633556783@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org [ Upstream commit f147384774a7b24dda4783a3dcd61af272757ea8 ] The commit af19b7ce76ba ("mmc: bcm2835: Avoid possible races on data requests") introduces a possible circular locking dependency, which is triggered by swapping to the sdhost interface. So instead of reintroduce the race condition again, we could also avoid this situation by using GFP_NOWAIT for the allocation of the DMA buffer descriptors. Reported-by: Aaro Koskinen Signed-off-by: Stefan Wahren Fixes: af19b7ce76ba ("mmc: bcm2835: Avoid possible races on data requests") Link: http://lists.infradead.org/pipermail/linux-rpi-kernel/2019-March/008615.html Signed-off-by: Vinod Koul Signed-off-by: Sasha Levin --- drivers/dma/bcm2835-dma.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/dma/bcm2835-dma.c b/drivers/dma/bcm2835-dma.c index ae10f5614f953..bf51192036378 100644 --- a/drivers/dma/bcm2835-dma.c +++ b/drivers/dma/bcm2835-dma.c @@ -674,7 +674,7 @@ static struct dma_async_tx_descriptor *bcm2835_dma_prep_slave_sg( d = bcm2835_dma_create_cb_chain(chan, direction, false, info, extra, frames, src, dst, 0, 0, - GFP_KERNEL); + GFP_NOWAIT); if (!d) return NULL; -- 2.20.1