 86fdcf23f4
			
		
	
	
		86fdcf23f4
		
	
	
	
	
		
			
			vnc joins the party ;) Also some s/head/seat/ to clarify. Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
		
			
				
	
	
		
			113 lines
		
	
	
		
			3.8 KiB
		
	
	
	
		
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			113 lines
		
	
	
		
			3.8 KiB
		
	
	
	
		
			Plaintext
		
	
	
	
	
	
| 
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| multiseat howto (with some multihead coverage)
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| ==============================================
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| 
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| host side
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| ---------
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| 
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| First you must compile qemu with a user interface supporting
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| multihead/multiseat and input event routing.  Right now this
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| list includes sdl2, gtk (both 2+3) and vnc:
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| 
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|   ./configure --enable-sdl --with-sdlabi=2.0
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| 
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| or
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| 
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|   ./configure --enable-gtk
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| 
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| 
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| Next put together the qemu command line (sdk/gtk):
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| 
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| qemu	-enable-kvm -usb $memory $disk $whatever \
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| 	-display [ sdl | gtk ] \
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| 	-vga std \
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| 	-device usb-tablet
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| 
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| That is it for the first seat, which will use the standard vga, the
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| standard ps/2 keyboard (implicitly there) and the usb-tablet.  Now the
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| additional switches for the second seat:
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| 
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| 	-device pci-bridge,addr=12.0,chassis_nr=2,id=head.2 \
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| 	-device secondary-vga,bus=head.2,addr=02.0,id=video.2 \
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| 	-device nec-usb-xhci,bus=head.2,addr=0f.0,id=usb.2 \
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| 	-device usb-kbd,bus=usb.2.0,port=1,display=video.2 \
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| 	-device usb-tablet,bus=usb.2.0,port=2,display=video.2
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| 
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| This places a pci bridge in slot 12, connects a display adapter and
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| xhci (usb) controller to the bridge.  Then it adds a usb keyboard and
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| usb mouse, both connected to the xhci and linked to the display.
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| 
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| The "display=video2" sets up the input routing.  Any input coming from
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| the window which belongs to the video.2 display adapter will be routed
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| to these input devices.
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| 
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| The sdl2 ui will start up with two windows, one for each display
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| device.  The gtk ui will start with a single window and each display
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| in a separate tab.  You can either simply switch tabs to switch heads,
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| or use the "View / Detach tab" menu item to move one of the displays
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| to its own window so you can see both display devices side-by-side.
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| 
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| For vnc some additional configuration on the command line is needed.
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| We'll create two vnc server instances, and bind the second one to the
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| second seat, simliar to input devices:
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| 
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| 	-display vnc=:1,id=primary \
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| 	-display vnc=:2,id=secondary,display=video.2
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| 
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| Connecting to vnc display :1 gives you access to the first seat, and
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| likewise connecting to vnc display :2 shows the second seat.
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| 
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| Note on spice: Spice handles multihead just fine.  But it can't do
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| multiseat.  For tablet events the event source is sent to the spice
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| agent.  But qemu can't figure it, so it can't do input routing.
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| Fixing this needs a new or extended input interface between
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| libspice-server and qemu.  For keyboard events it is even worse:  The
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| event source isn't included in the spice protocol, so the wire
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| protocol must be extended to support this.
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| 
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| 
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| guest side
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| ----------
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| 
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| You need a pretty recent linux guest.  systemd with loginctl.  kernel
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| 3.14+ with CONFIG_DRM_BOCHS enabled.  Fedora 20 will do.  Must be
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| fully updated for the new kernel though, i.e. the live iso doesn't cut
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| it.
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| 
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| Now we'll have to configure the guest.  Boot and login.  "lspci -vt"
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| should list the pci bridge with the display adapter and usb controller:
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| 
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|     [root@fedora ~]# lspci -vt
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|     -[0000:00]-+-00.0  Intel Corporation 440FX - 82441FX PMC [Natoma]
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|                [ ... ]
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|                \-12.0-[01]--+-02.0  Device 1234:1111
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|                             \-0f.0  NEC Corporation USB 3.0 Host Controller
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| 
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| Good.  Now lets tell the system that the pci bridge and all devices
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| below it belong to a separate seat by dropping a file into
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| /etc/udev/rules.d:
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| 
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|     [root@fedora ~]# cat /etc/udev/rules.d/70-qemu-autoseat.rules
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|     SUBSYSTEMS=="pci", DEVPATH=="*/0000:00:12.0", TAG+="seat", ENV{ID_AUTOSEAT}="1"
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| 
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| Reboot.  System should come up with two seats.  With loginctl you can
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| check the configuration:
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| 
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|     [root@fedora ~]# loginctl list-seats
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|     SEAT
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|     seat0
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|     seat-pci-pci-0000_00_12_0
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| 
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|     2 seats listed.
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| 
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| You can use "loginctl seat-status seat-pci-pci-0000_00_12_0" to list
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| the devices attached to the seat.
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| 
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| Background info is here:
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|   http://www.freedesktop.org/wiki/Software/systemd/multiseat/
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| 
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| Enjoy!
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| 
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| --
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| Gerd Hoffmann <kraxel@redhat.com>
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