VirtualBox

Changes between Version 4 and Version 5 of DynamicResizingDebug


Ignore:
Timestamp:
Oct 23, 2017 10:25:41 AM (7 years ago)
Author:
Michael Thayer
Comment:

--

Legend:

Unmodified
Added
Removed
Modified
  • DynamicResizingDebug

    v4 v5  
    77 * The basic mechanisms of dynamic resizing are described on another wiki page<1>.  The short summary is that the host sends "size hints" to the virtual machine (which consist of an interrupt on the virtual graphics card or the "guest" device and a way for the guest to ask for the details) and special "driver" modules from the Guest Additions ask the guest operating system to resize its virtual displays to match the hints.
    88
    9  * Every time the host sends a hint there will be a matching entry in the machine log file on the host ("VMMDev: SetVideoModeHint: Got a video mode hint (...)"  VMMDev is the "guest" device.  A matching hint may be sent to the graphics device).
     9 * The first requirement for dynamic resizing to work is for the Guest Additions to support it.  If you are using the normal user interface, you can check that the menu option to enable dynamic resizing can be enabled (meaning the Additions provide that support) and is enabled.
     10
     11 * Every time the host sends a hint there will be a matching entry in the machine log file on the host ("VMMDev: SetVideoModeHint: Got a video mode hint (...)"  VMMDev is the "guest" device.  A matching hint may be sent to the graphics device).  The next thing to check is whether these entries are appearing when you expect the guest to resize.
    1012
    1113 * If for whatever reason the guest operating system chooses to modify the requested size the host windows will try to follow that.  If the host window manager refuses the usual result is that the guest display will not fit the host window perfectly.  The guest drivers may also (Windows guests only) modify resize requests from the guest operating system to fit the size policy chosen by the user.
    1214
    1315 1. https://www.virtualbox.org/wiki/Guest_resizing
    14 
    15 == The default user interface ==
    16 
    17 The default user interface sends hints for every virtual screen each time one of the machine windows on the host is resized - as long as dynamic resizing is enabled (please check this).
    1816
    1917== Connecting to guests with VRDP ==
     
    2220
    2321== Guests running X.Org or Wayland ==
    24  * Guests running X.Org 1.17 or earlier need a "driver" module written for and loaded by the X server to control the virtual graphics card.  On all but the oldest supported versions of X.Org this module will be loaded automatically if it is put in the right directory on the guest (the Guest Additions do this when they are installed).  Old versions of X.Org (mostly Oracle/RedHat EL 5 and family) and XFree86 need the xorg.conf/XF86Config files to be changed to load the driver (the Additions usually get this right too).
    25  * If X.Org 1.17 or older is not found on a Linux guest system, and the kernel version is 3.11 or newer, a kernel driver for the graphics device will be built and installed.  This should work with X.Org 1.18 and newer as well as with Wayland.  This driver is Linux-only, but is written to be easily portable to other free/open-source guest operating systems which use the "drm" system for graphics.  If you are interested and able, feel free to say so on the development mailing list <1>.
    26  * Looking at the X.Org log file on the guest (usually /var/log/Xorg.0.log) often helps understand what is and is not working.
     22 * See the description of how the drivers work on the Guest Resizing page<1>.  If your guest is running X.Org or XFree86 as its main windowing system (not just XWayland) then the log file Xorg.0.log should show that it is using either the vboxvideo driver or the modesetting driver.  You should see lines starting with "vboxvideo" or "modeset" near the end of the file, not just at the beginning.  If not that is probably where the problem lies.
     23 * If you are running a Wayland compositor, the kernel vboxvideo driver should be running: type "lsmod| grep vboxvideo" into a terminal in the guest.
    2724 * If you are not sure if the kernel driver was set up correctly, see the information page about investigating that<2>.
    2825
    29  1. https://www.virtualbox.org/mailman/listinfo/vbox-dev
     26 1. https://www.virtualbox.org/wiki/Guest_resizing
    3027 2. https://www.virtualbox.org/wiki/LinuxAdditionsDebug

© 2023 Oracle
ContactPrivacy policyTerms of Use