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 0F3C1C43334 for ; Fri, 1 Jul 2022 09:04:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232788AbiGAJED (ORCPT ); Fri, 1 Jul 2022 05:04:03 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47408 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232975AbiGAJD6 (ORCPT ); Fri, 1 Jul 2022 05:03:58 -0400 Received: from madras.collabora.co.uk (madras.collabora.co.uk [46.235.227.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4FF452F005; Fri, 1 Jul 2022 02:03:57 -0700 (PDT) Received: from dimapc.. (109-252-118-164.nat.spd-mgts.ru [109.252.118.164]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) (Authenticated sender: dmitry.osipenko) by madras.collabora.co.uk (Postfix) with ESMTPSA id 085B26601995; Fri, 1 Jul 2022 10:03:54 +0100 (BST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=collabora.com; s=mail; t=1656666236; bh=RmdslR01N1MBAgH0PuAGwuMu+yy8zq6PlP6HQWG4wYg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=nHrfgsTuoRx8kOzlzVaWvklMsHeGG13lF79SxJNVQbDTriU/ELNxzpwemsXd/HJ6N tCgqYRHlBxMlkuqLP3wsvalsaUDzYtkehIk70F1HgELnpzz4FiOPyAtyY4y5UswUDN yAfyeqq7GMAYr/O9HKsoT/o1xbyv232TpRHF5nPetXV/bIdrNp6Q3ggZZvtcXuVttG Eg8Ad61hn6u3fNaXzZdHbQACed/6jgtaBhm55qJoAveWbHXi0f717HOAgAlTlD2G75 U7x206lJR1eFRFcfFdZcuxuWhuc+VzhdBI/8dKCJrNzOZ7u51CzPwOWOBQgagOvI9I rrmFFUrwntThg== From: Dmitry Osipenko To: David Airlie , Gerd Hoffmann , Gurchetan Singh , Chia-I Wu , Daniel Vetter , Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , Emil Velikov , =?UTF-8?q?Christian=20K=C3=B6nig?= , =?UTF-8?q?Thomas=20Hellstr=C3=B6m?= Cc: dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, Dmitry Osipenko , linux-tegra@vger.kernel.org, kernel@collabora.com, virtualization@lists.linux-foundation.org Subject: [PATCH v8 2/2] drm/gem: Don't map imported GEMs Date: Fri, 1 Jul 2022 12:02:40 +0300 Message-Id: <20220701090240.1896131-3-dmitry.osipenko@collabora.com> X-Mailer: git-send-email 2.36.1 In-Reply-To: <20220701090240.1896131-1-dmitry.osipenko@collabora.com> References: <20220701090240.1896131-1-dmitry.osipenko@collabora.com> 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 Drivers that use drm_gem_mmap() and drm_gem_mmap_obj() helpers don't handle imported dma-bufs properly, which results in mapping of something else than the imported dma-buf. On NVIDIA Tegra we get a hard lockup when userspace writes to the memory mapping of a dma-buf that was imported into Tegra's DRM GEM. Majority of DRM drivers prohibit mapping of the imported GEM objects. Mapping of imported GEMs require special care from userspace since it should sync dma-buf because mapping coherency of the exporter device may not match the DRM device. Let's prohibit the mapping for all DRM drivers for consistency. Suggested-by: Thomas Hellström Signed-off-by: Dmitry Osipenko --- drivers/gpu/drm/drm_gem.c | 4 ++++ drivers/gpu/drm/drm_gem_shmem_helper.c | 9 --------- 2 files changed, 4 insertions(+), 9 deletions(-) diff --git a/drivers/gpu/drm/drm_gem.c b/drivers/gpu/drm/drm_gem.c index 86d670c71286..fc9ec42fa0ab 100644 --- a/drivers/gpu/drm/drm_gem.c +++ b/drivers/gpu/drm/drm_gem.c @@ -1034,6 +1034,10 @@ int drm_gem_mmap_obj(struct drm_gem_object *obj, unsigned long obj_size, { int ret; + /* Don't allow imported objects to be mapped */ + if (obj->import_attach) + return -EINVAL; + /* Check for valid size. */ if (obj_size < vma->vm_end - vma->vm_start) return -EINVAL; diff --git a/drivers/gpu/drm/drm_gem_shmem_helper.c b/drivers/gpu/drm/drm_gem_shmem_helper.c index 8ad0e02991ca..6190f5018986 100644 --- a/drivers/gpu/drm/drm_gem_shmem_helper.c +++ b/drivers/gpu/drm/drm_gem_shmem_helper.c @@ -609,17 +609,8 @@ EXPORT_SYMBOL_GPL(drm_gem_shmem_vm_ops); */ int drm_gem_shmem_mmap(struct drm_gem_shmem_object *shmem, struct vm_area_struct *vma) { - struct drm_gem_object *obj = &shmem->base; int ret; - if (obj->import_attach) { - /* Drop the reference drm_gem_mmap_obj() acquired.*/ - drm_gem_object_put(obj); - vma->vm_private_data = NULL; - - return dma_buf_mmap(obj->dma_buf, vma, 0); - } - ret = drm_gem_shmem_get_pages(shmem); if (ret) { drm_gem_vm_close(vma); -- 2.36.1