The recent commits to add the parent device path broke Debian's kvm based QA 
workers for testing installer ISOs after a kernel upgrade from v6.8.12 to 
v6.9.7. For the details:

https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1075713

It took some time to  track it down since the superficial symptom appeared to 
involve the QXL driver. It turned out however to be the fbdev driver; 
specifically the change in the parent device path in sysfs reported between the 
two kernels:

6.8.12: 

/sys/class/graphics/fb0 -> 
../../devices/platform/vesa-framebuffer.0/graphics/fb0

6.9.7:

/sys/class/graphics/fb0 -> 
../../devices/pci0000:00/0000:00:01.0/vesa-framebuffer.0/graphics/fb0

This breaks xserver-xorg-core's libfbdevhw.so because it differentiates 
code-paths based on whether "devices/pci" is matched in the symlink.

See hw/xfree86/fbdevhw/fbdevhw.c::fbdev_open()

https://gitlab.freedesktop.org/xorg/xserver/-/blob/master/hw/xfree86/fbdevhw/fbdevhw.c?ref_type=heads#L381

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