From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:52478 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752479AbdGCL2d (ORCPT ); Mon, 3 Jul 2017 07:28:33 -0400 Subject: Patch "drm/etnaviv: trick drm_mm into giving out a low IOVA" has been added to the 4.9-stable tree To: l.stach@pengutronix.de, alexander.levin@verizon.com, gregkh@linuxfoundation.org, laanwj@gmail.com Cc: , From: Date: Mon, 03 Jul 2017 13:28:26 +0200 Message-ID: <149908130618521@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org List-ID: This is a note to let you know that I've just added the patch titled drm/etnaviv: trick drm_mm into giving out a low IOVA to the 4.9-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: drm-etnaviv-trick-drm_mm-into-giving-out-a-low-iova.patch and it can be found in the queue-4.9 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let know about it. >>From foo@baz Mon Jul 3 13:22:04 CEST 2017 From: Lucas Stach Date: Mon, 12 Dec 2016 16:15:17 +0100 Subject: drm/etnaviv: trick drm_mm into giving out a low IOVA From: Lucas Stach [ Upstream commit 3546fb0cdac25a79c89d87020566fab52b92867d ] After rollover of the IOVA space, we want to get a low IOVA address, otherwise the the games we play by remembering the last IOVA are pointless. When we search for a free hole with DRM_MM_SEARCH_DEFAULT, drm_mm will pop the next entry from the free holes stack, which will likely be a high IOVA. By using DRM_MM_SEARCH_BELOW we can trick drm_mm into reversing the search and provide us with a low IOVA. Signed-off-by: Lucas Stach Reviewed-by: Wladimir van der Laan Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- drivers/gpu/drm/etnaviv/etnaviv_mmu.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) --- a/drivers/gpu/drm/etnaviv/etnaviv_mmu.c +++ b/drivers/gpu/drm/etnaviv/etnaviv_mmu.c @@ -116,9 +116,14 @@ static int etnaviv_iommu_find_iova(struc struct list_head list; bool found; + /* + * XXX: The DRM_MM_SEARCH_BELOW is really a hack to trick + * drm_mm into giving out a low IOVA after address space + * rollover. This needs a proper fix. + */ ret = drm_mm_insert_node_in_range(&mmu->mm, node, size, 0, mmu->last_iova, ~0UL, - DRM_MM_SEARCH_DEFAULT); + mmu->last_iova ? DRM_MM_SEARCH_DEFAULT : DRM_MM_SEARCH_BELOW); if (ret != -ENOSPC) break; Patches currently in stable-queue which might be from l.stach@pengutronix.de are queue-4.9/drm-etnaviv-trick-drm_mm-into-giving-out-a-low-iova.patch