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X Session shows blank screen when switching TTYs

Posted: 17. May 2010, 12:16
by ddave1
Hi,

Having just updated VBox to 3.1.8, when I switch TTYs from 7 (XWin) to 1 and then back again, the virtual screen does not resize and the desktop does not re-appear. This leaves me with a blank screen which has the same resolution as the console, although I can see the mouse pointer which seems to change into its different modes depending on where it is on the screen.

Is anyone else seeing this behaviour?

BTW I'm running CentOS 5.4 (64 bit) with guest additions on a 32bit Windows XP host.

Apologies for the lack of info, I'm not sure what is required as this is my first post.

Thanks.

Re: X Session shows blank screen when swittching TTYs

Posted: 17. May 2010, 20:15
by Sasquatch
Welcome to the forums. If you don't know how to make a proper post (not much is wrong with it though), you could've checked the warning you got when creating the post. I.e. see Forum Posting Guide.

What happens if you swap to a TTY again and back? What happens if you leave the GUI while you have a terminal open and focussed, then when you return, type 'xrandr --auto'?

Re: X Session shows blank screen when swittching TTYs

Posted: 18. May 2010, 10:59
by ddave1
I can go to any of the console TTYs succesfully, but I can't go back to the X Session. The screen doesn't resize and I end up with a small black box the size of a console TTY with no graphics.

I have my virtual machine configured with an extra resolution through the custom VESA BIOS (1600x1200x32) as a default, and I also have it set to allow resolutions bigger than the virtual display:

**Global**

Code: Select all

Key: GUI/MaxGuestResolution, Value: any
**Machine**

Code: Select all

Key: CustomVideoMode1, Value: 1600x1200x32
Key: GUI/AutoresizeGuest, Value: off
My xrandr does not have an "--auto" argument, but running it gives the following:

Code: Select all

[dseares@localhost ~]$ xrandr
 SZ:    Pixels          Physical       Refresh
*0   1600 x 1200   ( 423mm x 318mm )  *60  
 1   1440 x 1050   ( 423mm x 318mm )   60  
 2   1280 x 960    ( 423mm x 318mm )   60  
 3   1024 x 768    ( 423mm x 318mm )   60  
 4    800 x 600    ( 423mm x 318mm )   60  
 5    640 x 480    ( 423mm x 318mm )   60  
Current rotation - normal
Current reflection - none
Rotations possible - normal 
Reflections possible - none

Re: X Session shows blank screen when swittching TTYs

Posted: 19. May 2010, 00:03
by Sasquatch
What happens if you remove the custom modes?

Re: X Session shows blank screen when switching TTYs

Posted: 19. May 2010, 10:44
by ddave1
No change.

When I look at the logs I find that on bootup, when the xsession starts I get:

Code: Select all

00:02:26.568 Guest Additions capability report: (0x4) seamless: no, hostWindowMapping: no, graphics: yes
00:02:26.571 Display::handleDisplayResize(): uScreenId = 0, pvVRAM=0a050000 w=1440 h=1050 bpp=32 cbLine=0x1680
00:02:26.571 VBVA: Enabled.
00:02:26.571 Guest Additions capability report: (0x4) seamless: no, hostWindowMapping: no, graphics: yes
When I switch to a console (TTY 1):

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00:03:37.148 Display::handleDisplayResize(): uScreenId = 0, pvVRAM=00000000 w=720 h=400 bpp=0 cbLine=0x0
00:03:37.148 VBVA: Disabled.
00:03:37.584 Display::handleDisplayResize(): uScreenId = 0, pvVRAM=0a050000 w=640 h=400 bpp=0 cbLine=0x280
00:03:37.810 Guest Additions capability report: (0x0) seamless: no, hostWindowMapping: no, graphics: no
00:03:37.819 Display::handleDisplayResize(): uScreenId = 0, pvVRAM=00000000 w=720 h=400 bpp=0 cbLine=0x0
When I switch back to the xsession (TTY 7):

Code: Select all

00:04:08.211 VBVA: Enabled.
And at this point all I get is a small blank screen, the only way to get my X display back is to restart X. I don't know what VBVA is but clearly there is no handleDisplayResize call, any ideas? What next??

Re: X Session shows blank screen when switching TTYs

Posted: 19. May 2010, 11:21
by ddave1
Ok, I can confirm that installing VBox 3.2 has fixed this issue.

Thanks.