Arch Linux

pdenapo

Member

Registered: 2024-07-23

Posts: 2

[SOLVED] Problems with modprobe dm_crypt

I'm using the kernel linux 6.9.10.arch1-1

I'm tryng to load the dm-crypt module for creating an encrypted partition as described at

https://wiki.archlinux.org/title/Dm-cry … encryption

The dm-crypt module seems not to be loaded in the kernel (at boot time) since lsmod reports this:

#lsmod | grep  crypt
crypto_simd            16384  1 aesni_intel
cryptd                 28672  2 crypto_simd,ghash_clmulni_intel
crypto_user            20480  0

Now, if I run as root

# modprobe dm-crypt
modprobe: FATAL: Module dm-crypt not found in directory /lib/modules/6.9.9-arch1-1

But the module is there, as I could check by running

# ls /lib/modules/6.9.10-arch1-1/kernel/drivers/md/*
/lib/modules/6.9.10-arch1-1/kernel/drivers/md/dm-bio-prison.ko.zst
/lib/modules/6.9.10-arch1-1/kernel/drivers/md/dm-bufio.ko.zst
/lib/modules/6.9.10-arch1-1/kernel/drivers/md/dm-cache.ko.zst
/lib/modules/6.9.10-arch1-1/kernel/drivers/md/dm-cache-smq.ko.zst
/lib/modules/6.9.10-arch1-1/kernel/drivers/md/dm-clone.ko.zst
/lib/modules/6.9.10-arch1-1/kernel/drivers/md/dm-crypt.ko.zst
/lib/modules/6.9.10-arch1-1/kernel/drivers/md/dm-delay.ko.zst
/lib/modules/6.9.10-arch1-1/kernel/drivers/md/dm-dust.ko.zst
/lib/modules/6.9.10-arch1-1/kernel/drivers/md/dm-ebs.ko.zst
/lib/modules/6.9.10-arch1-1/kernel/drivers/md/dm-era.ko.zst
/lib/modules/6.9.10-arch1-1/kernel/drivers/md/dm-flakey.ko.zst
/lib/modules/6.9.10-arch1-1/kernel/drivers/md/dm-historical-service-time.ko.zst
/lib/modules/6.9.10-arch1-1/kernel/drivers/md/dm-integrity.ko.zst
/lib/modules/6.9.10-arch1-1/kernel/drivers/md/dm-io-affinity.ko.zst
/lib/modules/6.9.10-arch1-1/kernel/drivers/md/dm-log.ko.zst
/lib/modules/6.9.10-arch1-1/kernel/drivers/md/dm-log-userspace.ko.zst
/lib/modules/6.9.10-arch1-1/kernel/drivers/md/dm-log-writes.ko.zst
/lib/modules/6.9.10-arch1-1/kernel/drivers/md/dm-mirror.ko.zst
/lib/modules/6.9.10-arch1-1/kernel/drivers/md/dm-mod.ko.zst
/lib/modules/6.9.10-arch1-1/kernel/drivers/md/dm-multipath.ko.zst
/lib/modules/6.9.10-arch1-1/kernel/drivers/md/dm-queue-length.ko.zst
/lib/modules/6.9.10-arch1-1/kernel/drivers/md/dm-raid.ko.zst
/lib/modules/6.9.10-arch1-1/kernel/drivers/md/dm-region-hash.ko.zst
/lib/modules/6.9.10-arch1-1/kernel/drivers/md/dm-round-robin.ko.zst
/lib/modules/6.9.10-arch1-1/kernel/drivers/md/dm-service-time.ko.zst
/lib/modules/6.9.10-arch1-1/kernel/drivers/md/dm-snapshot.ko.zst
/lib/modules/6.9.10-arch1-1/kernel/drivers/md/dm-switch.ko.zst
/lib/modules/6.9.10-arch1-1/kernel/drivers/md/dm-thin-pool.ko.zst
/lib/modules/6.9.10-arch1-1/kernel/drivers/md/dm-unstripe.ko.zst
/lib/modules/6.9.10-arch1-1/kernel/drivers/md/dm-verity.ko.zst
/lib/modules/6.9.10-arch1-1/kernel/drivers/md/dm-writecache.ko.zst
/lib/modules/6.9.10-arch1-1/kernel/drivers/md/dm-zero.ko.zst
/lib/modules/6.9.10-arch1-1/kernel/drivers/md/dm-zoned.ko.zst
/lib/modules/6.9.10-arch1-1/kernel/drivers/md/md-cluster.ko.zst
/lib/modules/6.9.10-arch1-1/kernel/drivers/md/md-mod.ko.zst
/lib/modules/6.9.10-arch1-1/kernel/drivers/md/raid0.ko.zst
/lib/modules/6.9.10-arch1-1/kernel/drivers/md/raid10.ko.zst
/lib/modules/6.9.10-arch1-1/kernel/drivers/md/raid1.ko.zst
/lib/modules/6.9.10-arch1-1/kernel/drivers/md/raid456.ko.zst

/lib/modules/6.9.10-arch1-1/kernel/drivers/md/bcache:
bcache.ko.zst

/lib/modules/6.9.10-arch1-1/kernel/drivers/md/dm-vdo:
dm-vdo.ko.zst

/lib/modules/6.9.10-arch1-1/kernel/drivers/md/persistent-data:
dm-persistent-data.ko.zst

So what is going on? How may I load that module into the kernel? modprobe supports .zst compressed modules?

Many thanks in advance for any help!

(I am somewhat new to Arch, but I've been using GNU/Linux since 1997...)

Last edited by pdenapo (2024-07-23 00:59:39)

loqs

Member

Registered: 2014-03-06

Posts: 17,916

Re: [SOLVED] Problems with modprobe dm_crypt

# modprobe dm-crypt
modprobe: FATAL: Module dm-crypt not found in directory /lib/modules/6.9.9-arch1-1

indicates the running kernel is 6.9.9-arch1-1.  You can confirm this by checking the output of `uname -a`.
Edit:
Was /boot mounted when you performed the last kernel update?

Last edited by loqs (2024-07-23 00:54:43)

pdenapo

Member

Registered: 2024-07-23

Posts: 2

Re: [SOLVED] Problems with modprobe dm_crypt

I see. It seems that I forgot to reboot after a kernel upgrade, so that the modules in that directory correspond to a different kernel. Many thanks! (I haven't noticed that!).

In many distributions, when you upgrade the kernel the old one is kept, just in case something fails when booting. I see this is not the case in Arch... (at least not the default).
Can I replicate this behavior in Arch?

loqs

Member

Registered: 2014-03-06

Posts: 17,916

Re: [SOLVED] Problems with modprobe dm_crypt

In many distributions, when you upgrade the kernel the old one is kept, just in case something fails when booting. I see this is not the case in Arch... (at least not the default).
Can I replicate this behavior in Arch?

See https://archlinux.org/packages/extra/an … ules-hook/ or https://aur.archlinux.org/packages/linux-versioned-bin