Source: debian-installer Followup-For: Bug #1075713 X-Debbugs-Cc: tj.iam...@proton.me
To be explicit this issue is not related to the QXL driver; that is a red herring. The problem is the fbdev driver is failing to handle the kernel's /dev/fb0. Digging further I compared the kernel configs and see nothing incriminating. I then started both ISOs using libvirt and the video QXL driver to easily enable network so I can transfer files in. Then using fetch-url I copied in fbset and captured info using: # fbset -i Both are identical. Then I started Xorg on both; although it runs on 20240628 it results in a black screen on VT2 since there is no window manager or anything else. However, on the console it reported a warning: (WW) FBDEV(0): The fbdev driver didn't call xf86SetGamma() to initialise the gamma values. (WW) FBDEV(0): PLEASE FIX THE `fbdev' DRIVER! But this is a long-standing issue, e.g. bug #747042 from 2014. The clue (from the GOOD image) I am following is: (II) FBDEV(2): using default device This message is only emitted by FBDevProbe() in src/fbdev.c ( from xserver-xorg-video-fbdev-0.5.0 ) There is another occurance but it is preceded by another message which we do not see, emitted by FBDevPciProbe(): ... "claimed PCI slot %d@%d:%d:%d\n" So now I'm working back through function FBDevProbe() to identify why variable pScreen is NULL at this point and causing the failure and hence not writing these messages. Build logs indicate the fbdev module is built with libpciaccess so that helps figure which preprocessor conditional code is compiled in and therefore executed. I intend to put gdbserver in the guest (if possible) and debug remotely. Once we know how it is failing that should lead to the cause.
