[arch-general] Kernel modules not loaded after Linux update

[Peter Nabbefeld]

Am 22.07.2018 um 17:07 schrieb Ralf Mardorf:
> [...]
> Could you please summarize what exactly doesn't work?
>
> IIUC you can't access the Internet with the computer where you got some
> messages about missing kernel modules. IIUC you successfully downgrade
> the kernel. We clarified that the linux-headers package is irrelevant.
> What happens now, when using the old kernel? Since the issue started
> after an update, what else did you update? See pacman.log.
1. I've run an update including a new Linux kernel (4.17.8).
2. After the update, systemd-modules-load.service refused to execute 
because of the crypto_user problem.
3. As a result of the failing modules load service, I couldn't access 
the internet, and even the mouse didn't work.
4. I then only downgraded the kernel to 4.17.2, and now everything seems 
to work (after first start Xfce4 didn't start correctly, probably some 
session parameters were badly set because of a previously faling start).

So, the situation is:
- After update to 4.17.8 Linux failed to load the needed modules.
- After downgrading *only* the kernel module to 4.17.2 the system is 
working again.

As obviously bluez is referring to "crypto_user" (which caused 
systemd-modules-load.service to fail), it may be some bad linking caused 
the problem (I'm not using DKMS).

I cannot find out, which cryptographic algorithm is used by bluez, but 
found by a diff compare, that my active config (/proc/config.gz) 
contains the following line:
CONFIG_CRYPTO_SALSA20_X86_64=m
This line is not contained in linux-header-4-17.8 - this may or may not 
be relevant, I'd need to make one more diff using linux-headers-4.17.2 
(probably tomorrow).

Kind  regards

Peter