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=-6.0 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE, SPF_PASS,T_DKIMWL_WL_HIGH,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 61C9FC2BCA1 for ; Fri, 7 Jun 2019 15:51:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 322B320840 for ; Fri, 7 Jun 2019 15:51:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1559922677; bh=lBUcbMCukAdxXX+qqRGYcXnacZxroOCWYxvBwQZ+3Jc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=xO04Iyz5GdzKL+dN5CCplRA8zILdGQv1WLI0mSEek/htp7nMAh0rr8ar7aAtaFQ46 br56zXniFubAYEhQB/pHY9WqIiLI4Jn8/Fi9Rw/25gSYYlW9BPtUSPSqTxTiJlpyWa wCPx+4TClKrMd6O09iVGVdT4ZAyEUlKfbMu9005M= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732274AbfFGPvQ (ORCPT ); Fri, 7 Jun 2019 11:51:16 -0400 Received: from mail.kernel.org ([198.145.29.99]:38204 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732249AbfFGPu5 (ORCPT ); Fri, 7 Jun 2019 11:50:57 -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 CFFC221473; Fri, 7 Jun 2019 15:50:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1559922657; bh=lBUcbMCukAdxXX+qqRGYcXnacZxroOCWYxvBwQZ+3Jc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=zkoDxwX1FsT7z38ySEDJZTmkSddImvxlOg45WhrecmSOucqLNM3lGbkP8OHpkIRxX /52Mo8OnrJc69XmzQ6wyuzhfDN4ty0nI86P6dOeDdq7XG5seFY0X1CfIY9lY7GywTF YaZ5CiFfwoIg6jmAN9rzLK9YyrcZmNm3LZM2nIWE= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Dmitry Osipenko , Thierry Reding Subject: [PATCH 5.1 71/85] drm/tegra: gem: Fix CPU-cache maintenance for BOs allocated using get_pages() Date: Fri, 7 Jun 2019 17:39:56 +0200 Message-Id: <20190607153857.031056807@linuxfoundation.org> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190607153849.101321647@linuxfoundation.org> References: <20190607153849.101321647@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Dmitry Osipenko commit 61b51fb51c01a519a249d28ec55c6513a13be5a3 upstream. The allocated pages need to be invalidated in CPU caches. On ARM32 the DMA_BIDIRECTIONAL flag only ensures that data is written-back to DRAM and the data stays in CPU cache lines. While the DMA_FROM_DEVICE flag ensures that the corresponding CPU cache lines are getting invalidated and nothing more, that's exactly what is needed for a newly allocated pages. This fixes randomly failing rendercheck tests on Tegra30 using the Opentegra driver for tests that use small-sized pixmaps (10x10 and less, i.e. 1-2 memory pages) because apparently CPU reads out stale data from caches and/or that data is getting evicted to DRAM at the time of HW job execution. Fixes: bd43c9f0fa1f ("drm/tegra: gem: Map pages via the DMA API") Cc: stable Signed-off-by: Dmitry Osipenko Signed-off-by: Thierry Reding Signed-off-by: Greg Kroah-Hartman --- drivers/gpu/drm/tegra/gem.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/drivers/gpu/drm/tegra/gem.c +++ b/drivers/gpu/drm/tegra/gem.c @@ -204,7 +204,7 @@ static void tegra_bo_free(struct drm_dev { if (bo->pages) { dma_unmap_sg(drm->dev, bo->sgt->sgl, bo->sgt->nents, - DMA_BIDIRECTIONAL); + DMA_FROM_DEVICE); drm_gem_put_pages(&bo->gem, bo->pages, true, true); sg_free_table(bo->sgt); kfree(bo->sgt); @@ -230,7 +230,7 @@ static int tegra_bo_get_pages(struct drm } err = dma_map_sg(drm->dev, bo->sgt->sgl, bo->sgt->nents, - DMA_BIDIRECTIONAL); + DMA_FROM_DEVICE); if (err == 0) { err = -EFAULT; goto free_sgt;