[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: Porting Xen in raspberry pi4B



Hi Vipul,

Sorry for the late reply. From the earlier logs that you sent, it looks
like everything should be working correctly. Specifically:

     vfb = ""
      1 = ""
       0 = ""
        frontend = "/local/domain/1/device/vfb/0"
        frontend-id = "1"
        online = "1"
        state = "4"
        vnc = "1"
        vnclisten = "127.0.0.1"
        vncdisplay = "0"
        vncunused = "1"
        sdl = "0"
        opengl = "0"
        feature-resize = "1"
        hotplug-status = "connected"
        request-update = "1"

state "4" means "connected". So I would expect that you should be able
to connect to the vnc server using vncviewer. You might not see anything
(black screen) but you should definitely be able to connect.

I wouldn't try to launch x11 in the guest just yet. fbcon in Linux is
enough to render something on the screen. You should be able to see the
Linux text-based console rendered graphically, connecting to it via vnc.

Sorry for the basic question, but have you tried all the following?

vncviewer 127.0.0.1:0
vncviewer 127.0.0.1:1
vncviewer 127.0.0.1:2
vncviewer 127.0.0.1:5900
vncviewer 127.0.0.1:5901
vncviewer 127.0.0.1:5902

Given that from the xenstore-ls logs everything seems to work correctly
I am not sure what else to suggest. You might have to add printf to QEMU
ui/vnc.c and hw/display/xenfb.c to see what is going wrong.

Cheers,

Stefano


On Mon, 7 Nov 2022, Vipul Suneja wrote:
> Hi Stefano,
> Thanks!
> 
> Any input further on "xenstore-ls" logs?
> 
> I am trying to run the x0vncserver & x11vnc server manually on guest 
> machine(xen_guest_image_minimal) image but it's failing with the below
> error.
> 
> root@raspberrypi4-64:/usr/bin# x0vncserver
> x0vncserver: unable to open display ""
> root@raspberrypi4-64:/usr/bin#
> root@raspberrypi4-64:/usr/bin# x11vnc
> ###############################################################
> #@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@#
> #@                                                           @#
> #@  **  WARNING  **  WARNING  **  WARNING  **  WARNING  **   @#
> #@                                                           @#
> #@        YOU ARE RUNNING X11VNC WITHOUT A PASSWORD!!        @#
> #@                                                           @#
> #@  This means anyone with network access to this computer   @#
> #@  may be able to view and control your desktop.            @#
> #@                                                           @#
> #@ >>> If you did not mean to do this Press CTRL-C now!! <<< @#
> #@                                                           @#
> #@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@#
> #@                                                           @#
> #@  You can create an x11vnc password file by running:       @#
> #@                                                           @#
> #@       x11vnc -storepasswd password /path/to/passfile      @#
> #@  or   x11vnc -storepasswd /path/to/passfile               @#
> #@  or   x11vnc -storepasswd                                 @#
> #@                                                           @#
> #@  (the last one will use ~/.vnc/passwd)                    @#
> #@                                                           @#
> #@  and then starting x11vnc via:                            @#
> #@                                                           @#
> #@      x11vnc -rfbauth /path/to/passfile                    @#
> #@                                                           @#
> #@  an existing ~/.vnc/passwd file from another VNC          @#
> #@  application will work fine too.                          @#
> #@                                                           @#
> #@  You can also use the -passwdfile or -passwd options.     @#
> #@  (note -passwd is unsafe if local users are not trusted)  @#
> #@                                                           @#
> #@  Make sure any -rfbauth and -passwdfile password files    @#
> #@  cannot be read by untrusted users.                       @#
> #@                                                           @#
> #@  Use x11vnc -usepw to automatically use your              @#
> #@  ~/.vnc/passwd or ~/.vnc/passwdfile password files.       @#
> #@  (and prompt you to create ~/.vnc/passwd if neither       @#
> #@  file exists.)  Under -usepw, x11vnc will exit if it      @#
> #@  cannot find a password to use.                           @#
> #@                                                           @#
> #@                                                           @#
> #@  Even with a password, the subsequent VNC traffic is      @#
> #@  sent in the clear.  Consider tunnelling via ssh(1):      @#
> #@                                                           @#
> #@    http://www.karlrunge.com/x11vnc/#tunnelling            @#
> #@                                                           @#
> #@  Or using the x11vnc SSL options: -ssl and -stunnel       @#
> #@                                                           @#
> #@  Please Read the documentation for more info about        @#
> #@  passwords, security, and encryption.                     @#
> #@                                                           @#
> #@    http://www.karlrunge.com/x11vnc/faq.html#faq-passwd    @#
> #@                                                           @#
> #@  To disable this warning use the -nopw option, or put     @#
> #@  'nopw' on a line in your ~/.x11vncrc file.               @#
> #@                                                           @#
> #@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@#
> ###############################################################
> 09/03/2018 12:58:41 x11vnc version: 0.9.16 lastmod: 2019-01-05  pid: 424
> 09/03/2018 12:58:41 XOpenDisplay("") failed.
> 09/03/2018 12:58:41 Trying again with XAUTHLOCALHOSTNAME=localhost ...
> 09/03/2018 12:58:41
> 09/03/2018 12:58:41 *** XOpenDisplay failed. No -display or DISPLAY.
> 09/03/2018 12:58:41 *** Trying ":0" in 4 seconds.  Press Ctrl-C to abort.
> 09/03/2018 12:58:41 *** 1 2 3 4
> 09/03/2018 12:58:45 XOpenDisplay(":0") failed.
> 09/03/2018 12:58:45 Trying again with XAUTHLOCALHOSTNAME=localhost ...
> 09/03/2018 12:58:45 XOpenDisplay(":0") failed.
> 09/03/2018 12:58:45 Trying again with unset XAUTHLOCALHOSTNAME ...
> 09/03/2018 12:58:45
> 
> 09/03/2018 12:58:45 ***************************************
> 09/03/2018 12:58:45 *** XOpenDisplay failed (:0)
> 
> *** x11vnc was unable to open the X DISPLAY: ":0", it cannot continue.
> *** There may be "Xlib:" error messages above with details about the failure.
> 
> Some tips and guidelines:
> 
> ** An X server (the one you wish to view) must be running before x11vnc is
>    started: x11vnc does not start the X server.  (however, see the -create
>    option if that is what you really want).
> 
> ** You must use -display <disp>, -OR- set and export your $DISPLAY
>    environment variable to refer to the display of the desired X server.
>  - Usually the display is simply ":0" (in fact x11vnc uses this if you forget
>    to specify it), but in some multi-user situations it could be ":1", ":2",
>    or even ":137".  Ask your administrator or a guru if you are having
>    difficulty determining what your X DISPLAY is.
> 
> ** Next, you need to have sufficient permissions (Xauthority)
>    to connect to the X DISPLAY.   Here are some Tips:
> 
>  - Often, you just need to run x11vnc as the user logged into the X session.
>    So make sure to be that user when you type x11vnc.
>  - Being root is usually not enough because the incorrect MIT-MAGIC-COOKIE
>    file may be accessed.  The cookie file contains the secret key that
>    allows x11vnc to connect to the desired X DISPLAY.
>  - You can explicitly indicate which MIT-MAGIC-COOKIE file should be used
>    by the -auth option, e.g.:
>        x11vnc -auth /home/someuser/.Xauthority -display :0
>        x11vnc -auth /tmp/.gdmzndVlR -display :0
>    you must have read permission for the auth file.
>    See also '-auth guess' and '-findauth' discussed below.
> 
> ** If NO ONE is logged into an X session yet, but there is a greeter login
>    program like "gdm", "kdm", "xdm", or "dtlogin" running, you will need
>    to find and use the raw display manager MIT-MAGIC-COOKIE file.
>    Some examples for various display managers:
> 
>      gdm:     -auth /var/gdm/:0.Xauth
>               -auth /var/lib/gdm/:0.Xauth
>      kdm:     -auth /var/lib/kdm/A:0-crWk72
>               -auth /var/run/xauth/A:0-crWk72
>      xdm:     -auth /var/lib/xdm/authdir/authfiles/A:0-XQvaJk
>      dtlogin: -auth /var/dt/A:0-UgaaXa
> 
>    Sometimes the command "ps wwwwaux | grep auth" can reveal the file 
> location.
> 
>    Starting with x11vnc 0.9.9 you can have it try to guess by using:
> 
>               -auth guess
> 
>    (see also the x11vnc -findauth option.)
> 
>    Only root will have read permission for the file, and so x11vnc must be run
>    as root (or copy it).  The random characters in the filenames will of 
> course
>    change and the directory the cookie file resides in is system dependent.
> 
> See also: http://www.karlrunge.com/x11vnc/faq.html
> 
> Regards,
> Vipul Kumar
> 
> On Thu, Nov 3, 2022 at 10:27 PM Vipul Suneja <vsuneja63@xxxxxxxxx> wrote:
>       Hi Stefano,
> Thanks!
> 
> I used xen-guest-image-minimal(simple console based image) as a guest with 
> fbcon & fbdev enabled in kernel configurations but still
> the same error can't open the display.
> below are the outcome of "xenstore-ls":
> 
> root@raspberrypi4-64:~/guest1# xenstore-ls
> tool = ""
>  xenstored = ""
> local = ""
>  domain = ""
>   0 = ""
>    control = ""
>     feature-poweroff = "1"
>     feature-reboot = "1"
>    domid = "0"
>    name = "Domain-0"
>    device-model = ""
>     0 = ""
>      backends = ""
>       console = ""
>       vkbd = ""
>       vfb = ""
>       qnic = ""
>      state = "running"
>     1 = ""
>      backends = ""
>       console = ""
>       vkbd = ""
>       vfb = ""
>       qnic = ""
>      state = "running"
>    backend = ""
>     vbd = ""
>      1 = ""
>       51712 = ""
>        frontend = "/local/domain/1/device/vbd/51712"
>        params = 
> "/home/root/guest2/xen-guest-image-minimal-raspberrypi4-64.ext3"
>        script = "/etc/xen/scripts/block"
>        frontend-id = "1"
>        online = "1"
>        removable = "0"
>        bootable = "1"
>        state = "4"
>        dev = "xvda"
>        type = "phy"
>        mode = "w"
>        device-type = "disk"
>        discard-enable = "1"
>        feature-max-indirect-segments = "256"
>        multi-queue-max-queues = "4"
>        max-ring-page-order = "4"
>        node = "/dev/loop0"
>        physical-device = "7:0"
>        physical-device-path = "/dev/loop0"
>        hotplug-status = "connected"
>        feature-flush-cache = "1"
>        discard-granularity = "4096"
>        discard-alignment = "0"
>        discard-secure = "0"
>        feature-discard = "1"
>        feature-barrier = "1"
>        feature-persistent = "1"
>        sectors = "1794048"
>        info = "0"
>        sector-size = "512"
>        physical-sector-size = "512"
>     vfb = ""
>      1 = ""
>       0 = ""
>        frontend = "/local/domain/1/device/vfb/0"
>        frontend-id = "1"
>        online = "1"
>        state = "4"
>        vnc = "1"
>        vnclisten = "127.0.0.1"
>        vncdisplay = "0"
>        vncunused = "1"
>        sdl = "0"
>        opengl = "0"
>        feature-resize = "1"
>        hotplug-status = "connected"
>        request-update = "1"
>     vkbd = ""
>      1 = ""
>       0 = ""
>        frontend = "/local/domain/1/device/vkbd/0"
>        frontend-id = "1"
>        online = "1"
>        state = "4"
>        feature-abs-pointer = "1"
>        feature-raw-pointer = "1"
>        hotplug-status = "connected"
>     console = ""
>      1 = ""
>       0 = ""
>        frontend = "/local/domain/1/console"
>        frontend-id = "1"
>        online = "1"
>        state = "1"
>        protocol = "vt100"
>     vif = ""
>      1 = ""
>       0 = ""
>        frontend = "/local/domain/1/device/vif/0"
>        frontend-id = "1"
>        online = "1"
>        state = "4"
>        script = "/etc/xen/scripts/vif-bridge"
>        mac = "e4:5f:01:cd:7b:dd"
>        bridge = "xenbr0"
>        handle = "0"
>        type = "vif"
>        hotplug-status = "connected"
>        feature-sg = "1"
>        feature-gso-tcpv4 = "1"
>        feature-gso-tcpv6 = "1"
>        feature-ipv6-csum-offload = "1"
>        feature-rx-copy = "1"
>        feature-xdp-headroom = "1"
>        feature-rx-flip = "0"
>        feature-multicast-control = "1"
>        feature-dynamic-multicast-control = "1"
>        feature-split-event-channels = "1"
>        multi-queue-max-queues = "4"
>        feature-ctrl-ring = "1"
>   1 = ""
>    vm = "/vm/d81ec5a9-5bf9-4f2b-89e8-0f60d6da948f"
>    name = "guest2"
>    cpu = ""
>     0 = ""
>      availability = "online"
>     1 = ""
>      availability = "online"
>    memory = ""
>     static-max = "2097152"
>     target = "2097152"
>     videoram = "0"
>    device = ""
>     suspend = ""
>      event-channel = ""
>     vbd = ""
>      51712 = ""
>       backend = "/local/domain/0/backend/vbd/1/51712"
>       backend-id = "0"
>       state = "4"
>       virtual-device = "51712"
>       device-type = "disk"
>       multi-queue-num-queues = "2"
>       queue-0 = ""
>        ring-ref = "8"
>        event-channel = "4"
>       queue-1 = ""
>        ring-ref = "9"
>        event-channel = "5"
>       protocol = "arm-abi"
>       feature-persistent = "1"
>     vfb = ""
>      0 = ""
>       backend = "/local/domain/0/backend/vfb/1/0"
>       backend-id = "0"
>       state = "4"
>       page-ref = "275022"
>       event-channel = "3"
>       protocol = "arm-abi"
>       feature-update = "1"
>     vkbd = ""
>      0 = ""
>       backend = "/local/domain/0/backend/vkbd/1/0"
>       backend-id = "0"
>       state = "4"
>       request-abs-pointer = "1"
>       page-ref = "275322"
>       page-gref = "1284"
>       event-channel = "10"
>     vif = ""
>      0 = ""
>       backend = "/local/domain/0/backend/vif/1/0"
>       backend-id = "0"
>       state = "4"
>       handle = "0"
>       mac = "e4:5f:01:cd:7b:dd"
>       mtu = "1500"
>       xdp-headroom = "0"
>       multi-queue-num-queues = "2"
>       queue-0 = ""
>        tx-ring-ref = "1280"
>        rx-ring-ref = "1281"
>        event-channel-tx = "6"
>        event-channel-rx = "7"
>       queue-1 = ""
>        tx-ring-ref = "1282"
>        rx-ring-ref = "1283"
>        event-channel-tx = "8"
>        event-channel-rx = "9"
>       request-rx-copy = "1"
>       feature-rx-notify = "1"
>       feature-sg = "1"
>       feature-gso-tcpv4 = "1"
>       feature-gso-tcpv6 = "1"
>       feature-ipv6-csum-offload = "1"
>    control = ""
>     shutdown = ""
>     feature-poweroff = "1"
>     feature-reboot = "1"
>     feature-suspend = ""
>     sysrq = ""
>     platform-feature-multiprocessor-suspend = "1"
>     platform-feature-xs_reset_watches = "1"
>    data = ""
>    drivers = ""
>    feature = ""
>    attr = ""
>    error = ""
>    domid = "1"
>    store = ""
>     port = "1"
>     ring-ref = "233473"
>    console = ""
>     backend = "/local/domain/0/backend/console/1/0"
>     backend-id = "0"
>     limit = "1048576"
>     type = "xenconsoled"
>     output = "pty"
>     tty = "/dev/pts/1"
>     port = "2"
>     ring-ref = "233472"
>     vnc-listen = "127.0.0.1"
>     vnc-port = "5900"
>    image = ""
>     device-model-pid = "788"
> vm = ""
>  d81ec5a9-5bf9-4f2b-89e8-0f60d6da948f = ""
>   name = "guest2"
>   uuid = "d81ec5a9-5bf9-4f2b-89e8-0f60d6da948f"
>   start_time = "1520600274.27"
> libxl = ""
>  1 = ""
>   device = ""
>    vbd = ""
>     51712 = ""
>      frontend = "/local/domain/1/device/vbd/51712"
>      backend = "/local/domain/0/backend/vbd/1/51712"
>      params = "/home/root/guest2/xen-guest-image-minimal-raspberrypi4-64.ext3"
>      script = "/etc/xen/scripts/block"
>      frontend-id = "1"
>      online = "1"
>      removable = "0"
>      bootable = "1"
>      state = "1"
>      dev = "xvda"
>      type = "phy"
>      mode = "w"
>      device-type = "disk"
>      discard-enable = "1"
>    vfb = ""
>     0 = ""
>      frontend = "/local/domain/1/device/vfb/0"
>      backend = "/local/domain/0/backend/vfb/1/0"
>      frontend-id = "1"
>      online = "1"
>      state = "1"
>      vnc = "1"
>      vnclisten = "127.0.0.1"
>      vncdisplay = "0"
>      vncunused = "1"
>      sdl = "0"
>      opengl = "0"
>    vkbd = ""
>     0 = ""
>      frontend = "/local/domain/1/device/vkbd/0"
>      backend = "/local/domain/0/backend/vkbd/1/0"
>      frontend-id = "1"
>      online = "1"
>      state = "1"
>    console = ""
>     0 = ""
>      frontend = "/local/domain/1/console"
>      backend = "/local/domain/0/backend/console/1/0"
>      frontend-id = "1"
>      online = "1"
>      state = "1"
>      protocol = "vt100"
>    vif = ""
>     0 = ""
>      frontend = "/local/domain/1/device/vif/0"
>      backend = "/local/domain/0/backend/vif/1/0"
>      frontend-id = "1"
>      online = "1"
>      state = "1"
>      script = "/etc/xen/scripts/vif-bridge"
>      mac = "e4:5f:01:cd:7b:dd"
>      bridge = "xenbr0"
>      handle = "0"
>      type = "vif"
>      hotplug-status = ""
>   type = "pvh"
>   dm-version = "qemu_xen"
> root@raspberrypi4-64:~/guest1#
> 
> Any input as per above? Looking forward to hearing from you.
> 
> Regards,
> Vipul Kumar
> 
> On Wed, Oct 26, 2022 at 5:21 AM Stefano Stabellini <sstabellini@xxxxxxxxxx> 
> wrote:
>       Hi Vipul,
> 
>       If you look at the QEMU logs, it says:
> 
>       VNC server running on 127.0.0.1:5900
> 
>       That is the VNC server you need to connect to. So in theory:
> 
>         vncviewer 127.0.0.1:5900
> 
>       should work correctly.
> 
> 
>       If you have:
> 
>         vfb = ["type=vnc"]
> 
>       in your xl config file and you have "fbdev" in your Linux guest, it
>       should work.
> 
>       If you connect to the VNC server but you get a black screen, it might be
>       a guest configuration issue. I would try with a simpler guest, text only
>       (no X11, no Wayland) and enable the fbdev console (fbcon). See
>       Documentation/fb/fbcon.rst in Linux. You should be able to see a
>       graphical console over VNC.
> 
>       If that works, then you know that the fbdev kernel driver (xen-fbfront)
>       works correctly.
> 
>       If it doesn't work, the output of "xenstore-ls" would be interesting.
> 
>       Cheers,
> 
>       Stefano
> 
> 
>       On Wed, 19 Oct 2022, Vipul Suneja wrote:
>       > Hi Stefano,
>       >
>       > Thanks for the response!
>       >
>       > I am following the same link you shared from the beginning. Tried the 
> command "vncviewer localhost:0" in DOM0 but same
>       issue "Can't open
>       > display", below are the logs:
>       >
>       > root@raspberrypi4-64:~# vncviewer localhost:0
>       >
>       > TigerVNC Viewer 64-bit v1.11.0
>       > Built on: 2020-09-08 12:16
>       > Copyright (C) 1999-2020 TigerVNC Team and many others (see README.rst)
>       > See https://www.tigervnc.org for information on TigerVNC.
>       > Can't open display:
>       >
>       > Below are the netstat logs, i couldn't see anything running at port 
> 5900 or 5901:
>       >
>       > root@raspberrypi4-64:~# netstat -tuwx
>       > Active Internet connections (w/o servers)
>       > Proto Recv-Q Send-Q Local Address           Foreign Address         
> State      
>       > tcp        0    164 192.168.1.39:ssh        192.168.1.38:37472      
> ESTABLISHED
>       > Active UNIX domain sockets (w/o servers)
>       > Proto RefCnt Flags       Type       State         I-Node Path
>       > unix  8      [ ]         DGRAM      CONNECTED      10565 /dev/log
>       > unix  3      [ ]         STREAM     CONNECTED      10891 
> /var/run/xenstored/socket
>       > unix  3      [ ]         STREAM     CONNECTED      13791
>       > unix  3      [ ]         STREAM     CONNECTED      10843 
> /var/run/xenstored/socket
>       > unix  3      [ ]         STREAM     CONNECTED      10573 
> /var/run/xenstored/socket
>       > unix  2      [ ]         DGRAM      CONNECTED      14510
>       > unix  3      [ ]         STREAM     CONNECTED      13249
>       > unix  2      [ ]         DGRAM      CONNECTED      13887
>       > unix  2      [ ]         DGRAM      CONNECTED      10599
>       > unix  3      [ ]         STREAM     CONNECTED      14005
>       > unix  3      [ ]         STREAM     CONNECTED      13258
>       > unix  3      [ ]         STREAM     CONNECTED      13248
>       > unix  3      [ ]         STREAM     CONNECTED      14003
>       > unix  3      [ ]         STREAM     CONNECTED      10572 
> /var/run/xenstored/socket
>       > unix  3      [ ]         STREAM     CONNECTED      10786 
> /var/run/xenstored/socket
>       > unix  3      [ ]         DGRAM      CONNECTED      13186
>       > unix  3      [ ]         STREAM     CONNECTED      10864 
> /var/run/xenstored/socket
>       > unix  3      [ ]         STREAM     CONNECTED      10812 
> /var/run/xenstored/socket
>       > unix  2      [ ]         DGRAM      CONNECTED      14083
>       > unix  3      [ ]         STREAM     CONNECTED      10813 
> /var/run/xenstored/socket
>       > unix  3      [ ]         STREAM     CONNECTED      14068
>       > unix  3      [ ]         STREAM     CONNECTED      13256
>       > unix  3      [ ]         STREAM     CONNECTED      10571 
> /var/run/xenstored/socket
>       > unix  3      [ ]         STREAM     CONNECTED      10842
>       > unix  3      [ ]         STREAM     CONNECTED      13985
>       > unix  3      [ ]         DGRAM      CONNECTED      13185
>       > unix  2      [ ]         STREAM     CONNECTED      13884
>       > unix  2      [ ]         DGRAM      CONNECTED      14528
>       > unix  2      [ ]         DGRAM      CONNECTED      13785
>       > unix  3      [ ]         STREAM     CONNECTED      14034
>       >
>       > Attaching xen log files of /var/log/xen.
>       > I didn't get the role of QEMU here because as mentioned earlier, I am 
> porting in raspberrypi 4B.
>       >
>       > Regards,
>       > Vipul Kumar
>       >
>       > On Wed, Oct 19, 2022 at 12:43 AM Stefano Stabellini 
> <sstabellini@xxxxxxxxxx> wrote:
>       >       It usually works the way it is described in the guide:
>       >
>       >     
>        
> https://www.virtuatopia.com/index.php?title=Configuring_a_VNC_based_Graphical_Console_for_a_Xen_Paravirtualized_domainU_Guest
>       >
>       >       You don't need to install any VNC-related server software 
> because it is
>       >       already provided by Xen (to be precise it is provided by QEMU 
> working
>       >       together with Xen.)
>       >
>       >       You only need the vnc client in dom0 so that you can connect, 
> but you
>       >       could also run the vnc client outside from another host. So 
> basically
>       >       the following should work when executed in Dom0 after creating 
> DomU:
>       >
>       >         vncviewer localhost:0
>       >
>       >       Can you attach the Xen and QEMU logs (/var/log/xen/*)? And also 
> use
>       >       netstat -taunp to check if there is anything running at port 
> 5900 or
>       >       5901?
>       >
>       >       Cheers,
>       >
>       >       Stefano
>       >
>       >
>       >       On Tue, 18 Oct 2022, Vipul Suneja wrote:
>       >       > Hi Stefano,
>       >       >
>       >       > Thanks for the response!
>       >       >
>       >       > I could install tigerVNC, x11vnc & libvncserver in Dom0 
> xen-image-minimal but only manage to install
>       libvncserver(couldn't
>       >       install tigervnc
>       >       > & x11vnc because of x11
>       >       > support missing, it's wayland) in DOMU custom graphical 
> image. I tried running vncviewer with IP address & port
>       in dom0 to
>       >       access the domu
>       >       > graphical image display as per below commands.
>       >       >  
>       >       >  vncviewer 192.168.1.42:5901
>       >       >  
>       >       >  But it showing can't open display, below are the logs:
>       >       >  
>       >       > root@raspberrypi4-64:~/guest1# vncviewer 192.168.1.42:5901
>       >       >
>       >       > TigerVNC Viewer 64-bit v1.11.0
>       >       > Built on: 2020-09-08 12:16
>       >       > Copyright (C) 1999-2020 TigerVNC Team and many others (see 
> README.rst)
>       >       > See https://www.tigervnc.org for information on TigerVNC.
>       >       > Can't open display:
>       >       > root@raspberrypi4-64:~/guest1#
>       >       >
>       >       > I am not exactly sure what the issue is but I thought only 
> libvncserver in DOMU could work to get access but it
>       did not
>       >       work. 
>       >       > If TigerVNC is the issue here then is there any other VNC 
> source which could be installed for both x11 &
>       wayland supported
>       >       images?
>       >       >
>       >       > Regards,
>       >       > Vipul Kumar
>       >       >
>       >       > On Tue, Oct 18, 2022 at 2:40 AM Stefano Stabellini 
> <sstabellini@xxxxxxxxxx> wrote:
>       >       >       VNC is typically easier to setup, because SDL needs 
> extra libraries at
>       >       >       build time and runtime. If QEMU is built without SDL 
> support it won't
>       >       >       start when you ask for SDL.
>       >       >
>       >       >       VNC should work with both x11 and wayland in your domU. 
> It doesn't work
>       >       >       at the x11 level, it exposes a special fbdev device in 
> your domU that
>       >       >       should work with:
>       >       >       - a graphical console in Linux domU
>       >       >       - x11
>       >       >       - wayland (but I haven't tested this so I am not 100% 
> sure about it)
>       >       >
>       >       >       When you say "it doesn't work", what do you mean? Do 
> you get a black
>       >       >       window?
>       >       >
>       >       >       You need CONFIG_XEN_FBDEV_FRONTEND in Linux domU
>       >       >       (drivers/video/fbdev/xen-fbfront.c). I would try to get 
> a graphical text
>       >       >       console up and running in your domU before attempting 
> x11/wayland.
>       >       >
>       >       >       Cheers,
>       >       >
>       >       >       Stefano
>       >       >
>       >       >       On Mon, 17 Oct 2022, Vipul Suneja wrote:
>       >       >       > Hi,
>       >       >       > Thanks!
>       >       >       >
>       >       >       > I have ported xen minimal image as DOM0 & custom 
> wayland GUI based image as DOMU in raspberry pi4B. I
>       am trying to
>       >       make GUI
>       >       >       display up
>       >       >       > for guest machine. I tried using sdl, included below 
> line in guest.conf file
>       >       >       > vfb= [ 'sdl=1' ]
>       >       >       >
>       >       >       > But it is throwing below error:
>       >       >       >
>       >       >       > root@raspberrypi4-64:~/guest1# xl create -c guest1.cfg
>       >       >       > Parsing config from guest1.cfg
>       >       >       > libxl: error: libxl_qmp.c:1400:qmp_ev_fd_callback: 
> Domain 3:error on QMP socket: Connection reset by
>       peer
>       >       >       > libxl: error: libxl_qmp.c:1439:qmp_ev_fd_callback: 
> Domain 3:Error happened with the QMP connection to
>       QEMU
>       >       >       > libxl: error: 
> libxl_dm.c:3351:device_model_postconfig_done: Domain 3:Post DM startup 
> configs failed,
>       rc=-26
>       >       >       > libxl: error: 
> libxl_create.c:1867:domcreate_devmodel_started: Domain 3:device model did not 
> start: -26
>       >       >       > libxl: error: 
> libxl_aoutils.c:646:libxl__kill_xs_path: Device Model already exited
>       >       >       > libxl: error: 
> libxl_domain.c:1183:libxl__destroy_domid: Domain 3:Non-existant domain
>       >       >       > libxl: error: 
> libxl_domain.c:1137:domain_destroy_callback: Domain 3:Unable to destroy guest
>       >       >       > libxl: error: libxl_domain.c:1064:domain_destroy_cb: 
> Domain 3:Destruction of domain failed
>       >       >       >
>       >       >       > Another way is VNC, i could install tigervnc in DOM0 
> but same i couldn't in guest machine because it
>       doesn't support
>       >       >       x11(supports wayland
>       >       >       > only). I am completely blocked here, Need your 
> support to enable the display up.
>       >       >       > Any alternative of VNC which could work in both x11 & 
> wayland supported images?
>       >       >       >
>       >       >       > Any input on VNC, SDL or any other way to proceed on 
> this? Looking forward to hearing from you.
>       >       >       >
>       >       >       > Regards,
>       >       >       > Vipul Kumar
>       >       >
>       >       >
>       >       >
>       >
>       >
>       >
> 
> 
> 

 


Rackspace

Lists.xenproject.org is hosted with RackSpace, monitoring our
servers 24x7x365 and backed by RackSpace's Fanatical Support®.