initrd lacks modules to mount boot image from http boot
Affects | Status | Importance | Assigned to | Milestone | |
---|---|---|---|---|---|
initramfs-tools (Ubuntu) |
Fix Released
|
Undecided
|
Unassigned | ||
Jammy |
Fix Released
|
Medium
|
Unassigned |
Bug Description
[ Impact ]
* If you use UEFI http boot to boot an image (rather than an EFI
executable) and get all the way to a normal userspace, you can
access the boot image as /dev/pmem0. But this is not accessible in
the initrd; presumably some modules are missing.
* This is desirable because then you can just feed an installer ISO to
a machine via http boot and the installer just works as normal
* Add support for physical pmem devices, and simulation thereof with
the memmap kernel command line parameter
* The initrd is larger
[ Test Plan ]
* unpack an initrd on a Jammy system with the generic kernel
metapackage with unmkinitramfs
* observe that the directories kernel/
are not present
* install the updated initramfs-tools packages from proposed
* again unpack an initrd on a Jammy system with the generic kernel
metapackage with unmkinitramfs
* observe that the directories kernel/
are present now
* reboot to confirm that the system still boots
* modify /etc/default/grub GRUB_CMDLINE_
memmap entry - memmap=1G!4G seems to work on many systems over 4G of
RAM, or do `dmesg | grep BIOS-e820` to observe the memory regions
and select a usable one.
* update-grub and reboot again
* a /dev/pmem device should now be present on the system
[ Where problems could occur ]
* The growth of the files in /boot will accelerate issues for users
who have a dedicated boot partition that is not large enough
[ Other Info ]
* Details on the memmap kernel command line parameter:
https:/
* PMEM simulation with memmap:
https:/
[ Original Bug Description ]
If you use UEFI http boot to boot an image (rather than an EFI executable) and get all the way to a normal userspace, you can access the boot image as /dev/pmem0. But this is not accessible in the initrd; presumably some modules are missing. Dimitri added some modules that are clearly going to be necessary (kernel/
This is desirable because then you can just feed an installer ISO to a machine via http boot and the installer just works as normal (the speed and, uh, quality, of the implementation of HTTP in a given machine's firmware may mean this isn't always the best option but it would be nice if it worked in case someone's machine actually does this well).
tags: | added: foundations-triage-discuss |
tags: |
added: foundations-todo removed: foundations-triage-discuss |
Changed in initramfs-tools (Ubuntu Jammy): | |
status: | New → Triaged |
importance: | Undecided → Medium |
Changed in initramfs-tools (Ubuntu Jammy): | |
assignee: | nobody → Dan Bungert (dbungert) |
description: | updated |
Changed in initramfs-tools (Ubuntu Jammy): | |
status: | Triaged → In Progress |
assignee: | Dan Bungert (dbungert) → nobody |
tags: |
added: verification-done verification-done-jammy removed: verification-needed verification-needed-jammy |
tags: | removed: foundations-todo |
You may need "nfit" module in the initrd too.