bug#39671: Something appears to disable linux kernel modules from loading.

[Joshua Branson]

So I just ran guix pull & reconfigure.

joshua@dobby /run/booted-system/kernel/lib/modules$ guix describe
Generation 36   Feb 20 2020 10:11:40    (current)
  jmacs 65b1737
    repository URL: https://notabug.org/jbranso/guix-packages.git
    branch: master
    commit: 65b17377136095935ef6da3a836142d56fecce2b
  guix bf8dfe3
    repository URL: https://git.savannah.gnu.org/git/guix.git
    branch: master
    commit: bf8dfe3df025e4ac80cccb87497b4f072ba10e2a


So I feel like Jack beat me to it,
but the contents of /proc/sys/kernel/modprobe are:

#+BEGIN_SRC sh
$ cat /proc/sys/kernel/modprobe
/gnu/store/daq5zs7ni529zh3xxgyhidna52wa17js-modprobe
#+END_SRC


#+BEGIN_SRC sh
cat /gnu/store/daq5zs7ni529zh3xxgyhidna52wa17js-modprobe
#!/gnu/store/1mkkv2caiqbdbbd256c4dirfi4kwsacv-guile-2.2.6/bin/guile 
--no-auto-compile
!#
(begin (setenv "LINUX_MODULE_DIRECTORY" 
"/run/booted-system/kernel/lib/modules") (apply execl 
"/run/current-system/profile/bin/modprobe" (cons 
"/run/current-system/profile/bin/modprobe" (cdr (command-line)))))~ $
#+END_SRC

Then I was just poking around.

#+BEGIN_SRC sh
~ $ cat /run/booted-system/kernel/lib/modules
Read error: Is a directory, /run/booted-system/kernel/lib/modules
~ $ cd /run/booted-system/kernel/lib/modules
/run/booted-system/kernel/lib/modules $ ls
5.4.21-gnu
/run/booted-system/kernel/lib/modules $ cd 5.4.21-gnu/
/run/booted-system/kernel/lib/modules/5.4.21-gnu $ ls
build   modules.alias      modules.builtin      modules.builtin.modinfo  
modules.dep.bin  modules.order    modules.symbols      source
kernel  modules.alias.bin  modules.builtin.bin  modules.dep              
modules.devname  modules.softdep  modules.symbols.bin
/run/booted-system/kernel/lib/modules/5.4.21-gnu $ cat modules.order
kernel/arch/x86/events/amd/power.ko
kernel/arch/x86/kernel/msr.ko
kernel/arch/x86/kernel/cpuid.ko
kernel/arch/x86/crypto/glue_helper.ko
kernel/arch/x86/crypto/des3_ede-x86_64.ko
kernel/arch/x86/crypto/camellia-x86_64.ko
kernel/arch/x86/crypto/blowfish-x86_64.ko
kernel/arch/x86/crypto/twofish-x86_64.ko
kernel/arch/x86/crypto/twofish-x86_64-3way.ko
... tons more modules...
kernel/drivers/gpu/drm/i915/i915.ko
kernel/drivers/net/ethernet/intel/e1000e/e1000e.ko
#+END_SRC

You'll notice that my i915 graphics and e1000e (ethernet) driver is
listed in that directory.

On my working system, these were the modules that lspci -v showed I was
using:

#+BEGIN_SRC sh :results output :exports both
lspci -v | grep "Kernel driver in"
#+END_SRC

#+RESULTS:
#+begin_example
        Kernel driver in use: i915
        Kernel driver in use: e1000e
        Kernel driver in use: uhci_hcd
        Kernel driver in use: uhci_hcd
        Kernel driver in use: uhci_hcd
        Kernel driver in use: ehci-pci
        Kernel driver in use: snd_hda_intel
        Kernel driver in use: pcieport
        Kernel driver in use: pcieport
        Kernel driver in use: pcieport
        Kernel driver in use: pcieport
        Kernel driver in use: pcieport
        Kernel driver in use: uhci_hcd
        Kernel driver in use: uhci_hcd
        Kernel driver in use: uhci_hcd
        Kernel driver in use: ehci-pci
        Kernel driver in use: lpc_ich
        Kernel driver in use: ata_piix
        Kernel driver in use: i801_smbus
        Kernel driver in use: yenta_cardbus
        Kernel driver in use: firewire_ohci
#+end_example

On the broken system, I am able to load my i915 and e1000e driver, but I
am not able to load yenta_cardbus.

#+BEGIN_SRC sh
$ sudo modprobe yenta_cardbus
modprobe: FATAL: Module yenta_cardbus not found in directory 
/run/booted-system/kernel/lib/modules/5.4.21-gnu
#+END_SRC

Sorry if I'm being repetitive.  I am just wanting to help.  :)

--
Joshua Branson
Sent from Emacs and Gnus