| |
| multiseat howto (with some multihead coverage) |
| ============================================== |
| |
| host side |
| --------- |
| |
| First you must compile qemu with a user interface supporting |
| multihead/multiseat and input event routing. Right now this |
| list includes sdl2 and gtk (both 2+3): |
| |
| ./configure --enable-sdl --with-sdlabi=2.0 |
| |
| or |
| |
| ./configure --enable-gtk |
| |
| |
| Next put together the qemu command line: |
| |
| qemu -enable-kvm -usb $memory $disk $whatever \ |
| -display [ sdl | gtk ] \ |
| -vga std \ |
| -device usb-tablet |
| |
| That is it for the first head, which will use the standard vga, the |
| standard ps/2 keyboard (implicitly there) and the usb-tablet. Now the |
| additional switches for the second head: |
| |
| -device pci-bridge,addr=12.0,chassis_nr=2,id=head.2 \ |
| -device secondary-vga,bus=head.2,addr=02.0,id=video.2 \ |
| -device nec-usb-xhci,bus=head.2,addr=0f.0,id=usb.2 \ |
| -device usb-kbd,bus=usb.2.0,port=1,display=video.2 \ |
| -device usb-tablet,bus=usb.2.0,port=2,display=video.2 |
| |
| This places a pci bridge in slot 12, connects a display adapter and |
| xhci (usb) controller to the bridge. Then it adds a usb keyboard and |
| usb mouse, both connected to the xhci and linked to the display. |
| |
| The "display=video2" sets up the input routing. Any input coming from |
| the window which belongs to the video.2 display adapter will be routed |
| to these input devices. |
| |
| The sdl2 ui will start up with two windows, one for each display |
| device. The gtk ui will start with a single window and each display |
| in a separate tab. You can either simply switch tabs to switch heads, |
| or use the "View / Detach tab" menu item to move one of the displays |
| to its own window so you can see both display devices side-by-side. |
| |
| Note on spice: Spice handles multihead just fine. But it can't do |
| multiseat. For tablet events the event source is sent to the spice |
| agent. But qemu can't figure it, so it can't do input routing. |
| Fixing this needs a new or extended input interface between |
| libspice-server and qemu. For keyboard events it is even worse: The |
| event source isn't included in the spice protocol, so the wire |
| protocol must be extended to support this. |
| |
| |
| guest side |
| ---------- |
| |
| You need a pretty recent linux guest. systemd with loginctl. kernel |
| 3.14+ with CONFIG_DRM_BOCHS enabled. Fedora 20 will do. Must be |
| fully updated for the new kernel though, i.e. the live iso doesn't cut |
| it. |
| |
| Now we'll have to configure the guest. Boot and login. "lspci -vt" |
| should list the pci bridge with the display adapter and usb controller: |
| |
| [root@fedora ~]# lspci -vt |
| -[0000:00]-+-00.0 Intel Corporation 440FX - 82441FX PMC [Natoma] |
| [ ... ] |
| \-12.0-[01]--+-02.0 Device 1234:1111 |
| \-0f.0 NEC Corporation USB 3.0 Host Controller |
| |
| Good. Now lets tell the system that the pci bridge and all devices |
| below it belong to a separate seat by dropping a file into |
| /etc/udev/rules.d: |
| |
| [root@fedora ~]# cat /etc/udev/rules.d/70-qemu-autoseat.rules |
| SUBSYSTEMS=="pci", DEVPATH=="*/0000:00:12.0", TAG+="seat", ENV{ID_AUTOSEAT}="1" |
| |
| Reboot. System should come up with two seats. With loginctl you can |
| check the configuration: |
| |
| [root@fedora ~]# loginctl list-seats |
| SEAT |
| seat0 |
| seat-pci-pci-0000_00_12_0 |
| |
| 2 seats listed. |
| |
| You can use "loginctl seat-status seat-pci-pci-0000_00_12_0" to list |
| the devices attached to the seat. |
| |
| Background info is here: |
| http://www.freedesktop.org/wiki/Software/systemd/multiseat/ |
| |
| Enjoy! |
| |
| -- |
| Gerd Hoffmann <kraxel@redhat.com> |
