08.05.2015 03:44, Bernhard Übelacker wrote: > Package: qemu-system-x86 > Version: 1:2.1+dfsg-11 > Severity: normal > Tags: upstream > > Dear Maintainer, > I quite regularly install some qemu VMs by just doing something like this: > qemu-system-x86_64 --enable-kvm -drive file=disk.img -cdrom cd.iso > > When cd.iso contains a Debian install cd then I encounter this strange > behaviour: > - qemu window openens > - bios screen is shown for half a second > - debian install cd boot screen is shown > - qemu window starts endlessly toggling between 640x480 and 720x400 > > One can then double click the window bar to hide the content, then this > flickering > stops, but now the content is scaled and the window will never change its size > when the guest resolution changes.
Ctrl+Alt+U resizes the window to match guest screen size. I can't reproduce this on a gnome, lxde or xfce system. Note that on all these systems, the guest X window does not have a title to click on, but you mentioned that in kde environment you can click on a title. Maybe this is some non-standard behavour of kde. > Here are some things probably also need to be met: > - Using KDE as DE. > I tried also starting it in an empty X server with just a xterm, there it > does > not flicker. With a instance of twm in this X server it is also not shown. > But by starting an instance of kwin in this empty X server it happens too. kwin, the kde window manager, who is responsible for drawing the title. It looks like the prob is a bug in kde (kwin), not in qemu. it is more,... > - When adding at the command line to boot from network (-boot n) some time > pass > by not finding the network server - then falling back to the CD and then the > flickering is not shown too. > - I observed a movement of the qemu window in the first second, like it is > created > without window borders and aligned to one screen border, and then the border > is added and therefore the window is moved. > Adding "-no-frame" avoids the flickering too, but then there is no frame ... So without a window frame kwin does not try to add a titlebar. > - By default it seems that qemu uses the SDL output (-display sdl) Yes, on debian we build qemu with sdl support and without gtk, because gtk display in qemu brings almost no features compared to sdl, but pulls in a significant lot of extra libraries. Is the problem present when you compile upstream source with gtk instead of sdl and run that? (The difference is the presense of menu bar in gtk varsion). If yes that will sort of confirm my theory. But if I'm right, the problem must be in sdl not qemu, who reacts to resize events from X when kwin is adding titlebar, resizes, but without the title, and kwin is adding the titlebar again. Or something like this. Oh well. (so it is not really "upstream" problem, but more like a prob with interaction between 2 pieces of 3rd-party software :) Thanks, /mjt -- To UNSUBSCRIBE, email to [email protected] with a subject of "unsubscribe". Trouble? Contact [email protected]
