[OS-BUILD PATCHv2 0/2] uki-virt: add virtiofs dracut module

[Gerd Hoffmann (via Email Bridge)]

From: Gerd Hoffmann on gitlab.com
Merge Request: https://gitlab.com/cki-project/kernel-ark/-/merge_requests/2817

Need to support root filesystem on virtiofs.

Signed-off-by: Gerd Hoffmann <kraxel(a)redhat.com&gt;

---
 redhat/dracut-virt.conf |  6 ++++++
 1 files changed, 6 insertions(+), 0 deletions(-)

[OS-BUILD PATCHv2 1/2] uki-virt: add virtiofs dracut module

[Gerd Hoffmann (via Email Bridge)]

From: Gerd Hoffmann <kraxel(a)redhat.com&gt;

uki-virt: add virtiofs dracut module

Need to support root filesystem on virtiofs.

Signed-off-by: Gerd Hoffmann <kraxel(a)redhat.com&gt;

diff --git a/redhat/dracut-virt.conf b/redhat/dracut-virt.conf
index blahblah..blahblah 100644
--- a/redhat/dracut-virt.conf
+++ b/redhat/dracut-virt.conf
@@ -14,6 +14,9 @@ dracutmodules+=" dm lvm rootfs-block fs-lib "
 # modules: tpm and crypto
 dracutmodules+=" crypt crypt-loop tpm2-tss "
 
+# modules: support root on virtiofs
+dracutmodules+=" virtiofs "
+
 # drivers: virtual buses, pci
 drivers+=" virtio-pci virtio-mmio "      # qemu-kvm
 drivers+=" hv-vmbus pci-hyperv "         # hyperv

--
https://gitlab.com/cki-project/kernel-ark/-/merge_requests/2817

[OS-BUILD PATCHv2 2/2] uki-virt: add systemd-sysext dracut module

[Gerd Hoffmann (via Email Bridge)]

From: Gerd Hoffmann <kraxel(a)redhat.com&gt;

uki-virt: add systemd-sysext dracut module

Allows the initrd being extended using sysext.

Signed-off-by: Gerd Hoffmann <kraxel(a)redhat.com&gt;

diff --git a/redhat/dracut-virt.conf b/redhat/dracut-virt.conf
index blahblah..blahblah 100644
--- a/redhat/dracut-virt.conf
+++ b/redhat/dracut-virt.conf
@@ -17,6 +17,9 @@ dracutmodules+=" crypt crypt-loop tpm2-tss "
 # modules: support root on virtiofs
 dracutmodules+=" virtiofs "
 
+# modules: use sysext images (see 'man systemd-sysext')
+dracutmodules+=" systemd-sysext "
+
 # drivers: virtual buses, pci
 drivers+=" virtio-pci virtio-mmio "      # qemu-kvm
 drivers+=" hv-vmbus pci-hyperv "         # hyperv

--
https://gitlab.com/cki-project/kernel-ark/-/merge_requests/2817

[DaanDeMeyer (via Email Bridge)]

From: DaanDeMeyer on gitlab.com
https://gitlab.com/cki-project/kernel-ark/-/merge_requests/2817#note_1694...

@kraxel.rh Any chance we could make virtiofs a builtin module? In that case we
don't need an initramfs at all and you can just make the kernel boot straight
off virtiofs.

[Gerd Hoffmann (via Email Bridge)]

From: Gerd Hoffmann on gitlab.com
https://gitlab.com/cki-project/kernel-ark/-/merge_requests/2817#note_1694...

We need the dracut module included nevertheless, to make root=virtiofs:<name>
work when booting with an initrd.

Independent from that we can consider switching virtiofs.ko to built-in, to
also allow booting without initrd.  No objections from my side, but it should
IMHO be an independent MR.

[DaanDeMeyer (via Email Bridge)]

From: DaanDeMeyer on gitlab.com
https://gitlab.com/cki-project/kernel-ark/-/merge_requests/2817#note_1695...

Note that with a systemd based initrd without dracut it's sufficient to add
"root=<tag> rootfstype=virtiofs rw" to boot from virtiofs (with or
without
initrd if virtiofs is builtin). I haven't had to add anything from dracut to
the initrd to get this working in mkosi. But I guess in this case the virtiofs
module is at least required to pull in the kernel module. Not sure what else
it does.

[Gerd Hoffmann (via Email Bridge)]

From: Gerd Hoffmann on gitlab.com
https://gitlab.com/cki-project/kernel-ark/-/merge_requests/2817#note_1696...

If you boot with an initrd it will be the initrd not the kernel which handles
the root= command line.  So maybe mkosi has built-in support for virtiofs, or
it passes control back to the kernel for cases it can't handle.  dracut
initrd's will error out without the virtiofs module.