[Qemu-devel] [BUG] Multiple graphical consoles are broken (black screen)

[Hervé Poussineau]

Hi,

MIPS Magnum machine emulation is quite specific because it instanciates
two graphical consoles.

This has worked for a while, up to following commit which breaks it
badly (qemu crashes):

commit 3023f3329d87a6203d03a0e9ccb948772940da96
Author: aliguori <address@hidden>
Date:   Fri Jan 16 19:04:14 2009 +0000

    graphical_console_init change (Stefano Stabellini)
    
    Patch 5/7
    
    This patch changes the graphical_console_init function to return an
    allocated DisplayState instead of a QEMUConsole.
    
    This patch contains just the graphical_console_init change and few other
    modifications mainly in console.c and vl.c.
    It was necessary to move the display frontends (e.g. sdl and vnc)
    initialization after machine->init in vl.c.
    
    This patch does *not* include any required changes to any device, these
    changes come with the following patches.
    
    Patch 6/7
    
    This patch changes the QEMUMachine init functions not to take a
    DisplayState as an argument because is not needed any more;
    
    In few places the graphic hardware initialization function was called
    only if DisplayState was not NULL, now they are always called.
    Apart from these cases, the rest are all mechanical substitutions.
    
    Patch 7/7
    
    This patch updates the graphic device code to use the new
    graphical_console_init function.
    
    As for the previous patch, in few places graphical_console_init was called
    only if DisplayState was not NULL, now it is always called.
    Apart from these cases, the rest are all mechanical substitutions.
    
    Signed-off-by: Stefano Stabellini <address@hidden>
    Signed-off-by: Anthony Liguori <address@hidden>


Few commits later, the following commit fixed the crash, but still kept the
second graphical console unusable: it stays blacks and the window size is not 
right.

commit 42aa98e8843aa8e3e1f35991f4be63eab2417e94
Author: aliguori <address@hidden>
Date:   Fri Jan 16 21:01:48 2009 +0000

    Remove assumption about a single graphic console.
    
    This fixes a fault with the jazz_led since it has two graphic consoles.
    
    Signed-off-by: Anthony Liguori <address@hidden>



Following patch is an attempt to work-around the problem, at least
for SDL display.

I hope someone will be able to pin point the problem, and find the right 
solution.
To reproduce the problem, run:

    mips64el-softmmu -M magnum -bios /path/to/NTPROM.raw

and try to switch to second console with Ctrl-Alt-2. You should see a small
console with some lines on it.

Hervé Poussineau (1):
  sdl: initialize all graphic consoles

 console.c |    3 +++
 vl.c      |   30 +++++++++++++++++++++---------
 2 files changed, 24 insertions(+), 9 deletions(-)

-- 
1.7.9