Niri fails to init display in QEMU, smithay error message

[jeancf]

Niri fails to init display in QEMU, smithay error message

[Drakulix]

Could you run drm_info in the VM and paste the output here? That would help debugging this.

[jeancf]

Here it is

sudo drm_info
Node: /dev/dri/card1
├───Driver: virtio_gpu (virtio GPU) version 0.1.0 (0)
│   ├───DRM_CLIENT_CAP_STEREO_3D supported
│   ├───DRM_CLIENT_CAP_UNIVERSAL_PLANES supported
│   ├───DRM_CLIENT_CAP_ATOMIC supported
│   ├───DRM_CLIENT_CAP_ASPECT_RATIO supported
│   ├───DRM_CLIENT_CAP_WRITEBACK_CONNECTORS supported
│   ├───DRM_CAP_DUMB_BUFFER = 1
│   ├───DRM_CAP_VBLANK_HIGH_CRTC = 1
│   ├───DRM_CAP_DUMB_PREFERRED_DEPTH = 0
│   ├───DRM_CAP_DUMB_PREFER_SHADOW = 0
│   ├───DRM_CAP_PRIME = 3
│   ├───DRM_CAP_TIMESTAMP_MONOTONIC = 1
│   ├───DRM_CAP_ASYNC_PAGE_FLIP = 0
│   ├───DRM_CAP_CURSOR_WIDTH = 64
│   ├───DRM_CAP_CURSOR_HEIGHT = 64
│   ├───DRM_CAP_ADDFB2_MODIFIERS = 0
│   ├───DRM_CAP_PAGE_FLIP_TARGET = 0
│   ├───DRM_CAP_CRTC_IN_VBLANK_EVENT = 1
│   ├───DRM_CAP_SYNCOBJ = 1
│   └───DRM_CAP_SYNCOBJ_TIMELINE = 1
├───Device: PCI 1af4:1050 Red Hat, Inc. Virtio 1.0 GPU
│   └───Available nodes: primary, render
├───Framebuffer size
│   ├───Width: [32, 8192]
│   └───Height: [32, 8192]
├───Connectors
│   └───Connector 0
│       ├───Object ID: 36
│       ├───Type: virtual
│       ├───Status: connected
│       ├───Physical size: 320x200 mm
│       ├───Subpixel: unknown
│       ├───Encoders: {0}
│       ├───Modes
│       │   ├───[email protected] preferred driver nhsync nvsync 
│       │   ├───[email protected] driver phsync pvsync 64:27 
│       │   ├───[email protected] driver phsync pvsync 256:135 
│       │   ├───[email protected] driver phsync pvsync 16:9 
│       │   ├───[email protected] driver phsync pvsync 16:9 
│       │   ├───[email protected] driver phsync pvsync 16:9 
│       │   ├───[email protected] driver nhsync pvsync 
│       │   ├───[email protected] driver phsync pvsync 64:27 
│       │   ├───[email protected] driver nhsync pvsync 
│       │   ├───[email protected] driver nhsync pvsync 
│       │   ├───[email protected] driver phsync pvsync 
│       │   ├───[email protected] driver nhsync pvsync 
│       │   ├───[email protected] driver nhsync nvsync 
│       │   ├───[email protected] driver phsync pvsync 16:9 
│       │   ├───[email protected] driver phsync pvsync 
│       │   ├───[email protected] driver nhsync pvsync 
│       │   ├───[email protected] driver nhsync pvsync 
│       │   ├───[email protected] driver phsync pvsync 
│       │   ├───[email protected] driver nhsync pvsync 
│       │   ├───[email protected] driver phsync pvsync 
│       │   ├───[email protected] driver phsync pvsync 
│       │   ├───[email protected] driver nhsync pvsync 
│       │   ├───[email protected] driver nhsync nvsync 
│       │   ├───[email protected] driver phsync pvsync 
│       │   ├───[email protected] driver nhsync nvsync 4:3 
│       │   └───[email protected] driver nhsync nvsync 
│       └───Properties
│           ├───"DPMS": enum {On, Standby, Suspend, Off} = On
│           ├───"link-status": enum {Good, Bad} = Good
│           ├───"non-desktop" (immutable): range [0, 1] = 0
│           ├───"TILE" (immutable): blob = 0
│           ├───"CRTC_ID" (atomic): object CRTC = 35
│           └───"EDID" (immutable): blob = 38
├───Encoders
│   └───Encoder 0
│       ├───Object ID: 37
│       ├───Type: virtual
│       ├───CRTCS: {0}
│       └───Clones: {0}
├───CRTCs
│   └───CRTC 0
│       ├───Object ID: 35
│       ├───Legacy info
│       │   ├───Mode: [email protected] preferred driver nhsync nvsync 
│       │   └───Gamma size: 0
│       └───Properties
│           ├───"ACTIVE" (atomic): range [0, 1] = 1
│           ├───"MODE_ID" (atomic): blob = 40
│           │   └───[email protected] preferred driver nhsync nvsync 
│           ├───"OUT_FENCE_PTR" (atomic): range [0, UINT64_MAX] = 0
│           └───"VRR_ENABLED": range [0, 1] = 0
└───Planes
    └───Plane 0
        ├───Object ID: 31
        ├───CRTCs: {0}
        ├───Legacy info
        │   ├───FB ID: 39
        │   │   ├───Object ID: 39
        │   │   ├───Size: 1280x800
        │   │   ├───Format: XRGB8888 (0x34325258)
        │   │   └───Planes:
        │   │       └───Plane 0: offset = 0, pitch = 5120 bytes
        │   └───Formats:
        │       └───XRGB8888 (0x34325258)
        └───Properties
            ├───"type" (immutable): enum {Overlay, Primary, Cursor} = Primary
            ├───"FB_ID" (atomic): object framebuffer = 39
            │   ├───Object ID: 39
            │   ├───Size: 1280x800
            │   ├───Format: XRGB8888 (0x34325258)
            │   └───Planes:
            │       └───Plane 0: offset = 0, pitch = 5120 bytes
            ├───"IN_FENCE_FD" (atomic): srange [-1, INT32_MAX] = -1
            ├───"CRTC_ID" (atomic): object CRTC = 35
            ├───"CRTC_X" (atomic): srange [INT32_MIN, INT32_MAX] = 0
            ├───"CRTC_Y" (atomic): srange [INT32_MIN, INT32_MAX] = 0
            ├───"CRTC_W" (atomic): range [0, INT32_MAX] = 1280
            ├───"CRTC_H" (atomic): range [0, INT32_MAX] = 800
            ├───"SRC_X" (atomic): range [0, UINT32_MAX] = 0
            ├───"SRC_Y" (atomic): range [0, UINT32_MAX] = 0
            ├───"SRC_W" (atomic): range [0, UINT32_MAX] = 1280
            ├───"SRC_H" (atomic): range [0, UINT32_MAX] = 800
            └───"FB_DAMAGE_CLIPS" (atomic): blob = 42

[jeancf]

Is there an obvious error in the plane buffer that smithay cannot use?

[Drakulix]

The current theory is, that it doesn't work, because the driver supports atomic but not DRM_CAP_ADDFB2_MODIFIERS (as stated by your log). It might very well be, that we have that as an implicit assumption layed out somewhere in smithays code, but so far I had no time to dig deeper into it.

[jeancf]

I see. Thanks for the feedback.

It would be nice for Niri to be usable in a QEMU VM to let people (like me) tinker with it and contribute. I will wait, thanks.

[jeancf]

I rebuilt Niri with the latest smithay git commits and it is working now. Thanks.

[Drakulix]

Great!

Glad to know this fixed niri in qemu as well: #1432