unmkinitramfs fails with lz4 compressed initrds

This bug was fixed in the package initramfs-tools - 0.133ubuntu8

---------------
initramfs-tools (0.133ubuntu8) eoan; urgency=medium

  * Switch back to lz4 by default.
  * Patch unmkinitramfs to cat possible lz4 archives first, as lz4 is
    particular about enforcing .lz4 file extensions when operating on
    files. LP: #1832108

 -- Dimitri John Ledkov <email address hidden> Mon, 10 Jun 2019 00:21:17 +0100

This seems to be working on Bionic:

root@bb-qemu:~# echo asd | lz4 > asd
root@bb-qemu:~# file asd
asd: LZ4 compressed data (v1.4+)
root@bb-qemu:~# lz4cat -t asd
root@bb-qemu:~# echo $?
0

Hello Dimitri, or anyone else affected,

Accepted initramfs-tools into disco-proposed. The package will build now and be available at https://launchpad.net/ubuntu/+source/initramfs-tools/0.131ubuntu19.1 in a few hours, and then in the -proposed repository.

Please help us by testing this new package. See https://wiki.ubuntu.com/Testing/EnableProposed for documentation on how to enable and use -proposed. Your feedback will aid us getting this update out to other Ubuntu users.

If this package fixes the bug for you, please add a comment to this bug, mentioning the version of the package you tested and change the tag from verification-needed-disco to verification-done-disco. If it does not fix the bug for you, please add a comment stating that, and change the tag to verification-failed-disco. In either case, without details of your testing we will not be able to proceed.

Further information regarding the verification process can be found at https://wiki.ubuntu.com/QATeam/PerformingSRUVerification . Thank you in advance for helping!

N.B. The updated package will be released to -updates after the bug(s) fixed by this package have been verified and the package has been in -proposed for a minimum of 7 days.

The cosmic upload is blocked as we are waiting on verification of bug 1778844.

Reproduce the problem:

# dpkg-query -W initramfs-tools lz4
initramfs-tools 0.131ubuntu19
lz4 1.8.3-1ubuntu1

# sed -i 's/gzip/lz4/' /etc/initramfs-tools/initramfs.conf

# update-initramfs -c -k test

# lsinitramfs /boot/initrd.img-test
cpio: premature end of archive

===

# sed 's/-updates/-proposed/' -i /etc/apt/sources.list
# apt update
# dpkg-query -W initramfs-tools lz4
initramfs-tools 0.131ubuntu19.1
lz4 1.8.3-1ubuntu1

# lsinitramfs /boot/initrd.img-test
...
all the files are listed

This bug was fixed in the package initramfs-tools - 0.131ubuntu19.1

---------------
initramfs-tools (0.131ubuntu19.1) disco; urgency=medium

  * Patch unmkinitramfs to cat possible lz4 archives first, as lz4 is
    particular about enforcing .lz4 file extensions when operating on
    files. LP: #1832108

 -- Dimitri John Ledkov <email address hidden> Tue, 11 Jun 2019 16:17:51 +0100

The verification of the Stable Release Update for initramfs-tools has completed successfully and the package has now been released to -updates. Subsequently, the Ubuntu Stable Release Updates Team is being unsubscribed and will not receive messages about this bug report. In the event that you encounter a regression using the package from -updates please report a new bug using ubuntu-bug and tag the bug report regression-update so we can easily find any regressions.

Testing on cm3

switch to partitions #0, OK
mmc0(part 0) is current device
LOADBOOTENV
** Unable to read file uEnv.txt **
Running uenvcmd ...
ENVCMD
6644040 bytes read in 282 ms (22.5 MiB/s) (this is kernel)
2852487 bytes read in 123 ms (22.1 MiB/s) (this is initrd)
FAT: Misaligned buffer address (023b8687)
42049 bytes read in 14 ms (2.9 MiB/s)

2019-07-04T15:35:05.998027+0000 localhost kernel: Unpacking initramfs...
2019-07-04T15:35:05.998089+0000 localhost kernel: Freeing initrd memory: 2828K

(not sure if above is true gzip decompression speed of initramfs or not)

Watching telnet, from reboot until "Press enter to configure" took 41.84s (42.25s 41.50s).

$ file initrd.img
initrd.img: LZMA compressed data, streamed

 ls -latr initrd-lzma.img initrd-uncompressed.img initrd-gzip.img initrd-lz49l.img | sort
-rwxr-xr-x 1 xnox xnox 2852487 Jul 5 00:19 initrd-lzma.img
-rwxr-xr-x 1 xnox xnox 3889013 Jul 5 00:21 initrd-gzip.img
-rwxr-xr-x 1 xnox xnox 4466915 Jul 5 00:22 initrd-lz49l.img
-rwxr-xr-x 1 xnox xnox 7330304 Jul 5 00:20 initrd-uncompressed.img

uncompressed:

7330304 bytes read in 311 ms (22.5 MiB/s)
reboot time 39.39s
2019-07-04T16:54:38.050180+0000 localhost kernel: Unpacking initramfs...
2019-07-04T16:54:38.050253+0000 localhost kernel: Freeing initrd memory: 7200K

lz4

6644040 bytes read in 282 ms (22.5 MiB/s)
4466915 bytes read in 191 ms (22.3 MiB/s)
reboot time 39.49s
2019-07-04T16:54:38.012115+0000 localhost kernel: Unpacking initramfs...
2019-07-04T16:54:38.012178+0000 localhost kernel: Initramfs unpacking failed: Decoding failed
2019-07-04T16:54:38.012246+0000 localhost kernel: Freeing initrd memory: 4404K

gzip

6644040 bytes read in 283 ms (22.4 MiB/s)
3889013 bytes read in 167 ms (22.2 MiB/s)
reboot time 40.31s
2019-07-04T16:54:37.997158+0000 localhost kernel: Unpacking initramfs...
2019-07-04T16:54:37.997230+0000 localhost kernel: Freeing initrd memory: 3840K

@xnox,

Could you SRU this to bionic too? It becomes problematic to try to probe at an initramfs file from eoan when you're in bionic otherwise.