Bug#790561: After upgrading udev from 215-18 to 220-7 or 221-1, the system is unbootable afterwards

[Ansgar Burchardt]

Axel Beckert <abe at debian.org> writes:
> Michael Biebl wrote:
>> Am 30.06.2015 um 17:52 schrieb Klaus Ethgen:
>> > # CONFIG_FHANDLE is not set
>> 
>> E.g. that one is missing.
>> If you compile your own kernel, you should make sure all requirements
>> listed at [1] are met. I didn't check all other options, but your
>> problem is most likely related to that.
>
> In the past the udev package IIRC checked for such issues in preinst
> and refused to upgrade if it found newly required configurations not
> being present.
>
> Any reason why this hasn't been done in this case?

udev.preinst looks like it tries to do so (check_kernel_features), but
it depends on several factors:

 - /proc/kallsyms needs to be present for the symbols check. This might
   not be enabled on custom kernels.
 - udev must be active

There is even a check for CONFIG_FHANDLE:

    - open_by_handle_at(2)  (CONFIG_FHANDLE)

But I wouldn't trust it too much; after all this check is probably not
the most tested part of the package...

Ansgar