After an upgrade of libgl1-mesa-glx to version 17.2.2-1 and a
reboot, the system hangs during startup and has become
inaccessible. lightdm's x-0.log and Xorg.0.log logfiles mention an
error: undefined symbol: _glapi_tls_Current.
The problem is described in several bug reports:
The solution seems simple:
The following packages will be REMOVED:
But how do you do that with an inaccessible system? The system can be booted in recovery mode, and the change can be made there. But the network is not yet up and running.
I solved the problem as follows.
If everything went well, the prompt of lightdm appears. The first upgrade problem in years in testing that made the system unusable, has been solved. Thanks are due to the people who analyzed the problem and described their solution in the bug reports.
Note: The syslog of the inaccessible system suggests that the
system is up and running: Oct 18 10:07:07 vuurvlinder systemd:
Startup finished in 5.917s (kernel) + 20.713s (userspace) =
26.630s. Then it may be possible to log into the system from
another computer and perform the package change, instead of the