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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id BCC71C433FE for ; Wed, 19 Oct 2022 09:25:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233156AbiJSJZk (ORCPT ); Wed, 19 Oct 2022 05:25:40 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43634 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233675AbiJSJYZ (ORCPT ); Wed, 19 Oct 2022 05:24:25 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id EDFE2C4D9A; Wed, 19 Oct 2022 02:11:07 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id C597B61750; Wed, 19 Oct 2022 09:07:29 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id DD321C433D7; Wed, 19 Oct 2022 09:07:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1666170449; bh=CDFKxDXed4seug1ukSk9Zm+SmC8qh5flXF0DuqIbwBM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=FeNp7U5kpEwGIQSux/oUB7J9rZ1sgOgQJ+3A/cQqS7aS4e13GoNXxTYzfK3Qmz5uT c7G2ThgjRlE1UoZxg3o570gtgCgtXdAW4TsMx6lDTTf31b+K+5hRUp1ezG3uNs+21v 6T73J3U44xhRWO4EX8OHrC/fTOHLsdWGKuDGf8tk= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, =?UTF-8?q?Marek=20Beh=C3=BAn?= , Christoph Hellwig , "Russell King (Oracle)" , Sasha Levin Subject: =?UTF-8?q?=5BPATCH=206=2E0=20659/862=5D=20=3D=3FUTF-8=3Fq=3FARM/dma-mapp=3DD1=3D96ng=3A=3D20dont=3D20override=3D20-=3Edma=3D5Fcohe=3F=3D=20=3D=3FUTF-8=3Fq=3Frent=3D20when=3D20set=3D20from=3D20a=3D20bus=3D20notifier=3F=3D?= Date: Wed, 19 Oct 2022 10:32:26 +0200 Message-Id: <20221019083319.087440003@linuxfoundation.org> X-Mailer: git-send-email 2.38.0 In-Reply-To: <20221019083249.951566199@linuxfoundation.org> References: <20221019083249.951566199@linuxfoundation.org> User-Agent: quilt/0.67 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Christoph Hellwig [ Upstream commit 49bc8bebae79c8516cb12f91818f3a7907e3ebce ] Commit ae626eb97376 ("ARM/dma-mapping: use dma-direct unconditionally") caused a regression on the mvebu platform, wherein devices that are dma-coherent are marked as dma-noncoherent, because although mvebu_hwcc_notifier() after that commit still marks then as coherent, the arm_coherent_dma_ops() function, which is called later, overwrites this setting, since it is being called from drivers/of/device.c with coherency parameter determined by of_dma_is_coherent(), and the device-trees do not declare the 'dma-coherent' property. Fix this by defaulting never clearing the dma_coherent flag in arm_coherent_dma_ops(). Fixes: ae626eb97376 ("ARM/dma-mapping: use dma-direct unconditionally") Reported-by: Marek Behún Signed-off-by: Christoph Hellwig Reviewed-by: Russell King (Oracle) Tested-by: Marek Behún Signed-off-by: Sasha Levin --- arch/arm/mm/dma-mapping.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c index 089c9c644cce..bfc7476f1411 100644 --- a/arch/arm/mm/dma-mapping.c +++ b/arch/arm/mm/dma-mapping.c @@ -1769,8 +1769,16 @@ static void arm_teardown_iommu_dma_ops(struct device *dev) { } void arch_setup_dma_ops(struct device *dev, u64 dma_base, u64 size, const struct iommu_ops *iommu, bool coherent) { - dev->archdata.dma_coherent = coherent; - dev->dma_coherent = coherent; + /* + * Due to legacy code that sets the ->dma_coherent flag from a bus + * notifier we can't just assign coherent to the ->dma_coherent flag + * here, but instead have to make sure we only set but never clear it + * for now. + */ + if (coherent) { + dev->archdata.dma_coherent = true; + dev->dma_coherent = true; + } /* * Don't override the dma_ops if they have already been set. Ideally -- 2.35.1