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We are experiencing the wierd phenomenon that graphics is partially mirrored in our guest Scientific Linux 6 VM running as linux guest of Windox 7x64 host.
Running cadence virtuoso waveform viewer (part of chip design CAD software), we see that the output of the waveform viewer is completely mirrored in x and y.
This started with 4.2.10. Our VB and extensions are all up to date.
Everything else looks OK.
This might be due to some really old rendering code used in Cadence.
Has anyone else seen anything like this? I put the image below
Thanks

I see that none of the other visible windows are affected, so this isn't some kind of mess-up in VBox graphics memory addressing. It looks to me like a bug in whatever guest application rendered that window. As a total guess I would say that that entire window is rendered using vector graphics, including the text, and somehow it ended up using a negative scale factor in the x direction only.

Yes, that's correct, just that one application is affected, but it was never a problem before for us on any VM and only appeared after recent VB update.
We will try to roll back to see if that fixes the problem.
We suspect that the waveform viewer application rendering core was written many years ago using a legacy graphics rendering engine that no one at cadence understands anymore.
Something in that rendering pipeline breaks with some update to the graphics on the VM. Just a guess but we will try to verify now if rolling back fixes it.

Just remember that VirtualBox (the VM hardware simulation) knows nothing about GUI concepts such as windows, captions and fonts. It's just a simulated graphics array and a display. Whatever the guest writes into graphics memory, that's what will appear in the window. If it was any kind of random corruption, or if the entire display was flipped then I could believe a VirtualBox bug. Since it's contained to one window, and only the client area of that window, and since only the guest OS knows anything about windows... it has to be a guest problem IMHO.

Edit:  Actually, on second look it seems to be mirrored in the y direction too doesn't it... I don't know why I thought that wasn't the case before. Also if I scroll down I see little bitmapped toolbar icons which are also flipped. So, my vector graphics idea is wrong. In that case what this looks like to me is that the data (complete with labels and toolbar) is rendered to a bitmap and then blitted onto the client area of the parent window: for some reason the blit function flips the x and y axis. I guess this could be a bug in VBox 2D or 3D overlay support, though I still doubt it - nobody else has reported this.

Thanks for taking the time to think about it. We tried to revert back to earlier Vbox version 4.1.4 but then X11 would not start and when we tried to install guest additions that also failed with error (unfortunately not captured) that X11 was wrong version. (I could be wrong about this).
X11 in our ScientificLinux 6 guest VM is version 1.13. We will try again to revert to earlier VBox and see if possibly it could be something in blitting implementation that only affects this single particular waveform viewer tool.

By the way, one possible clue is that after latest update to VBox to 4.2.10 we could boot SciLinux 6 but X11 would not start (stuck after atd in boot output). Only after terminal installation of the 4.2.10 guest additions were we able to reboot and see X11 starting with login screen. No idea if this might be related, but at least it relates to X11. And after booting with successful X11 launch checking the /var/log/Xorg.0.log we see no errors.

Now I verified on an earlier VBox (4.2.6) that had not been updated the graphics is OK.

I think we will just have to roll back all our VMs to this release for now until we figure out what is going on.

Screen shot below

Or post a ticket at bugtracker before you do and send the guests log file and link to here. Otherwise it will never get fixed.

If you could also check what happens if you upgrade to 4.2.10, but leave the GAs at 4.2.6 - that would be handy to know. Basically, is the problem with the GAs?

Eventually we sorted this out: It was not due to VB, but rather to a bug in some update to the X server or some component of it. The graphics works fine with X version 1.10.6 but break with version 1.13.x. We don't know why the X update (that occurred silently in Scientific Linux) breaks this blitting (or whatever it is).

The fix for us was to use yum to roll back to an earlier version of X and to prevent automatic update by editing /etc/yum.conf as root and putting in a line
exclude=xorg-x11-server*

We have no idea how to sort out the root cause of the bug however.