From patchwork Wed Mar 1 18:54:32 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Rob Clark X-Patchwork-Id: 13156338 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 gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 6CAEDC7EE2D for ; Wed, 1 Mar 2023 18:54:41 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 3E3C810E1E7; Wed, 1 Mar 2023 18:54:40 +0000 (UTC) Received: from mail-pj1-x102a.google.com (mail-pj1-x102a.google.com [IPv6:2607:f8b0:4864:20::102a]) by gabe.freedesktop.org (Postfix) with ESMTPS id 375BF10E1E7 for ; Wed, 1 Mar 2023 18:54:38 +0000 (UTC) Received: by mail-pj1-x102a.google.com with SMTP id qa18-20020a17090b4fd200b0023750b675f5so214157pjb.3 for ; Wed, 01 Mar 2023 10:54:38 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; t=1677696877; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:from:to:cc:subject:date:message-id:reply-to; bh=qIhBybknQqSSCYaaXviqV/xcYtdK0wdqPp4paRUIIu0=; b=pHLFh6/NTQjadjGwr/P+ltAcpWdPLZqgVM9lMSDvqBcLYPNruHqX400/0+7OvKxxyd yAQMukFfkTmQ6rqX91Tt2iIS7TZyzTjor7Tb6V+eXkyDqtGqt1/bwY6PiEaOpPlN8hJL j1kX75ajoyEMSH3BzjnZaDXr//eko5EC5mmkyzSIq21N6ttdhwJaRajFta7XhPJt2n9h s7gLYsD5C5jVHsXJw2EdstgQTa8jOw/ugze68oLP116+agbM1do6xZ0paG6q9BJsizam 3W2NyRi/mFWRRLsMVq6cLDdUNPCsz5qqNVxKuvTaQjfSj7OI+I3gv4+SxXs+pwRiVhkc r7vg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; t=1677696877; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=qIhBybknQqSSCYaaXviqV/xcYtdK0wdqPp4paRUIIu0=; b=ZTpMkFXxZeuAJgANsvyy7SgzHJEXnvkKbVZwGdxE2Ln3l1dYSj5U8ylZWowCQvWK4K gB28tdC4avTM2fNVBzE+P5vRbXHP/hx/Q4SgIJdHrARiqae4KF+44cm4nuUUj1rxCuq1 aVDkRsvHR3abfOWkGv2tYNqISFcM/tLyPyYkK5G0I20S7n7+UNoUxdj9omJqY3azuHm6 ES0lWQNoQhpiRczmDgN+g/9xkGBpQezIbsO3yOBUNbJJM8UJuhHAGNX+r8l4H5DU8Ghc dvrU7fl8s0JjFl5vcqmMQEgelGK73eeedmpYlOVjBmnU7EpjKTQ9e4QpksZCJPGHVN8w N6yw== X-Gm-Message-State: AO0yUKUibYFkIlk9u8t5DVIYMRDaZBMMcbPeCy6nAVmBEnCj+jnJ4GU1 cJGsXIl05qXfKjzOFSSU2hIMBZAStZA= X-Google-Smtp-Source: AK7set+PMn6YNoOuC6/NpsrFMwgq4P7BDo+JBRMQgrh+GPtAgWrragL0O79B+cVbgIzsDzIXyTIlUw== X-Received: by 2002:a05:6a20:6922:b0:ce:33ea:a07c with SMTP id q34-20020a056a20692200b000ce33eaa07cmr2376980pzj.30.1677696877104; Wed, 01 Mar 2023 10:54:37 -0800 (PST) Received: from localhost ([2a00:79e1:abd:4a00:61b:48ed:72ab:435b]) by smtp.gmail.com with ESMTPSA id i21-20020a633c55000000b005034a46fbf7sm5563111pgn.28.2023.03.01.10.54.36 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 01 Mar 2023 10:54:36 -0800 (PST) From: Rob Clark To: dri-devel@lists.freedesktop.org Subject: [PATCH v5] drm/virtio: Add option to disable KMS support Date: Wed, 1 Mar 2023 10:54:32 -0800 Message-Id: <20230301185432.3010939-1-robdclark@gmail.com> X-Mailer: git-send-email 2.39.1 MIME-Version: 1.0 X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Rob Clark , Dmitry Osipenko , Ryan Neph , open list , Javier Martinez Canillas , Gurchetan Singh , Gerd Hoffmann , David Airlie , "open list:VIRTIO GPU DRIVER" Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" From: Rob Clark Add a build option to disable modesetting support. This is useful in cases where the guest only needs to use the GPU in a headless mode, or (such as in the CrOS usage) window surfaces are proxied to a host compositor. As the modesetting ioctls are a big surface area for potential security bugs to be found (it's happened in the past, we should assume it will again in the future), it makes sense to have a build option to disable those ioctls in cases where they serve no legitimate purpose. v2: Use more if (IS_ENABLED(...)) v3: Also permit the host to advertise no scanouts v4: Spiff out commit msg v5: Make num_scanouts==0 and DRM_VIRTIO_GPU_KMS=n behave the same Signed-off-by: Rob Clark Reviewed-by: Dmitry Osipenko Reviewed-by: Javier Martinez Canillas Acked-by: Gerd Hoffmann --- drivers/gpu/drm/virtio/Kconfig | 11 ++++++++++ drivers/gpu/drm/virtio/Makefile | 5 ++++- drivers/gpu/drm/virtio/virtgpu_drv.c | 4 ++++ drivers/gpu/drm/virtio/virtgpu_drv.h | 10 +++++++++ drivers/gpu/drm/virtio/virtgpu_kms.c | 33 +++++++++++++++++----------- 5 files changed, 49 insertions(+), 14 deletions(-) diff --git a/drivers/gpu/drm/virtio/Kconfig b/drivers/gpu/drm/virtio/Kconfig index 51ec7c3240c9..ea06ff2aa4b4 100644 --- a/drivers/gpu/drm/virtio/Kconfig +++ b/drivers/gpu/drm/virtio/Kconfig @@ -11,3 +11,14 @@ config DRM_VIRTIO_GPU QEMU based VMMs (like KVM or Xen). If unsure say M. + +config DRM_VIRTIO_GPU_KMS + bool "Virtio GPU driver modesetting support" + depends on DRM_VIRTIO_GPU + default y + help + Enable modesetting support for virtio GPU driver. This can be + disabled in cases where only "headless" usage of the GPU is + required. + + If unsure, say Y. diff --git a/drivers/gpu/drm/virtio/Makefile b/drivers/gpu/drm/virtio/Makefile index b99fa4a73b68..24c7ebe87032 100644 --- a/drivers/gpu/drm/virtio/Makefile +++ b/drivers/gpu/drm/virtio/Makefile @@ -4,8 +4,11 @@ # Direct Rendering Infrastructure (DRI) in XFree86 4.1.0 and higher. virtio-gpu-y := virtgpu_drv.o virtgpu_kms.o virtgpu_gem.o virtgpu_vram.o \ - virtgpu_display.o virtgpu_vq.o \ + virtgpu_vq.o \ virtgpu_fence.o virtgpu_object.o virtgpu_debugfs.o virtgpu_plane.o \ virtgpu_ioctl.o virtgpu_prime.o virtgpu_trace_points.o +virtio-gpu-$(CONFIG_DRM_VIRTIO_GPU_KMS) += \ + virtgpu_display.o + obj-$(CONFIG_DRM_VIRTIO_GPU) += virtio-gpu.o diff --git a/drivers/gpu/drm/virtio/virtgpu_drv.c b/drivers/gpu/drm/virtio/virtgpu_drv.c index ae97b98750b6..add075681e18 100644 --- a/drivers/gpu/drm/virtio/virtgpu_drv.c +++ b/drivers/gpu/drm/virtio/virtgpu_drv.c @@ -172,6 +172,10 @@ MODULE_AUTHOR("Alon Levy"); DEFINE_DRM_GEM_FOPS(virtio_gpu_driver_fops); static const struct drm_driver driver = { + /* + * If KMS is disabled DRIVER_MODESET and DRIVER_ATOMIC are masked + * out via drm_device::driver_features: + */ .driver_features = DRIVER_MODESET | DRIVER_GEM | DRIVER_RENDER | DRIVER_ATOMIC, .open = virtio_gpu_driver_open, .postclose = virtio_gpu_driver_postclose, diff --git a/drivers/gpu/drm/virtio/virtgpu_drv.h b/drivers/gpu/drm/virtio/virtgpu_drv.h index af6ffb696086..ffe8faf67247 100644 --- a/drivers/gpu/drm/virtio/virtgpu_drv.h +++ b/drivers/gpu/drm/virtio/virtgpu_drv.h @@ -426,8 +426,18 @@ virtio_gpu_cmd_set_scanout_blob(struct virtio_gpu_device *vgdev, uint32_t x, uint32_t y); /* virtgpu_display.c */ +#if defined(CONFIG_DRM_VIRTIO_GPU_KMS) int virtio_gpu_modeset_init(struct virtio_gpu_device *vgdev); void virtio_gpu_modeset_fini(struct virtio_gpu_device *vgdev); +#else +static inline int virtio_gpu_modeset_init(struct virtio_gpu_device *vgdev) +{ + return 0; +} +static inline void virtio_gpu_modeset_fini(struct virtio_gpu_device *vgdev) +{ +} +#endif /* virtgpu_plane.c */ uint32_t virtio_gpu_translate_format(uint32_t drm_fourcc); diff --git a/drivers/gpu/drm/virtio/virtgpu_kms.c b/drivers/gpu/drm/virtio/virtgpu_kms.c index 27b7f14dae89..61a1afe2c8c8 100644 --- a/drivers/gpu/drm/virtio/virtgpu_kms.c +++ b/drivers/gpu/drm/virtio/virtgpu_kms.c @@ -223,21 +223,26 @@ int virtio_gpu_init(struct virtio_device *vdev, struct drm_device *dev) num_scanouts, &num_scanouts); vgdev->num_scanouts = min_t(uint32_t, num_scanouts, VIRTIO_GPU_MAX_SCANOUTS); - if (!vgdev->num_scanouts) { - DRM_ERROR("num_scanouts is zero\n"); - ret = -EINVAL; - goto err_scanouts; + + if (IS_ENABLED(CONFIG_DRM_VIRTIO_GPU_KMS) || !vgdev->num_scanouts) { + DRM_INFO("KMS disabled\n"); + vgdev->num_scanouts = 0; + vgdev->has_edid = false; + dev->driver_features &= ~(DRIVER_MODESET | DRIVER_ATOMIC); + } else { + DRM_INFO("number of scanouts: %d\n", num_scanouts); } - DRM_INFO("number of scanouts: %d\n", num_scanouts); virtio_cread_le(vgdev->vdev, struct virtio_gpu_config, num_capsets, &num_capsets); DRM_INFO("number of cap sets: %d\n", num_capsets); - ret = virtio_gpu_modeset_init(vgdev); - if (ret) { - DRM_ERROR("modeset init failed\n"); - goto err_scanouts; + if (vgdev->num_scanouts) { + ret = virtio_gpu_modeset_init(vgdev); + if (ret) { + DRM_ERROR("modeset init failed\n"); + goto err_scanouts; + } } virtio_device_ready(vgdev->vdev); @@ -246,10 +251,12 @@ int virtio_gpu_init(struct virtio_device *vdev, struct drm_device *dev) virtio_gpu_get_capsets(vgdev, num_capsets); if (vgdev->has_edid) virtio_gpu_cmd_get_edids(vgdev); - virtio_gpu_cmd_get_display_info(vgdev); - virtio_gpu_notify(vgdev); - wait_event_timeout(vgdev->resp_wq, !vgdev->display_info_pending, - 5 * HZ); + if (vgdev->num_scanouts) { + virtio_gpu_cmd_get_display_info(vgdev); + virtio_gpu_notify(vgdev); + wait_event_timeout(vgdev->resp_wq, !vgdev->display_info_pending, + 5 * HZ); + } return 0; err_scanouts: