hanging at boot for about 30 seconds since upgrade to bionic

[karlsebal]

[SRU Justification]
A regression in initramfs-tools causes it to autogenerate config in the initramfs saying to resume from any available swap devices, even if the swap device is ephemeral (i.e. swap encrypted with a random key). This adds an inappropriate 30-second boot delay to any system with randomly-crypted swap, which includes any system that was installed with encrypted home directories in earlier releases.

[Test case]
1. Install the ecryptfs-utils package.
2. Enable encrypted swap by running 'sudo ecryptfs-setup-swap'.
3. Run 'update-initramfs -u' to regenerate the initramfs.
4. Reboot.
5. Verify that dmesg shows a 30-second delay before mounting the root filesystem.
6. Install initramfs-tools from bionic-proposed.
7. Reboot.
8. Verify that dmesg no longer shows a 30-second delay before mounting the root filesystem.

[Regression potential]
This makes changes to shell scripts, and shell is a perilous language. An unnoticed bug could cause all initramfs generation, and thus all kernel installation, to fail for some users. A regression could also cause a user to lose hiberation support that they currently have.

[Original description]
Since upgrade to Bionic ubuntu is hanging at boot for about 30s. A `dmesg` shows

```
[ 3.407230] clocksource: Switched to clocksource tsc
[ 34.632583] EXT4-fs (sda2): mounted filesystem with ordered data mode. Opts: (null)
```

This is 100% reproducable and is always 30s minimum. I do not know in which package to report this properly – please excuse me.

ProblemType: Bug
DistroRelease: Ubuntu 18.04
Package: ubuntu-release-upgrader-core 1:18.04.17
ProcVersionSignature: Ubuntu 4.15.0-20.21-lowlatency 4.15.17
Uname: Linux 4.15.0-20-lowlatency x86_64
ApportVersion: 2.20.9-0ubuntu7
Architecture: amd64
CrashDB: ubuntu
CurrentDesktop: i3
Date: Fri May 18 09:40:59 2018
EcryptfsInUse: Yes
InstallationDate: Installed on 2014-06-03 (1444 days ago)
InstallationMedia: Ubuntu 14.04 LTS "Trusty Tahr" - Release amd64 (20140417)
PackageArchitecture: all
SourcePackage: ubuntu-release-upgrader
Symptom: release-upgrade
UpgradeStatus: Upgraded to bionic on 2018-05-13 (5 days ago)
VarLogDistupgradeAptclonesystemstate.tar.gz:
 Error: command ['pkexec', 'cat', '/var/log/dist-upgrade/apt-clone_system_state.tar.gz'] failed with exit code 127: polkit-agent-helper-1: error response to PolicyKit daemon: GDBus.Error:org.freedesktop.PolicyKit1.Error.Failed: No session for cookie
 Error executing command as another user: Not authorized

 This incident has been reported.

[karlsebal (karlsebal)]

This is a duplicate of https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1460447 and solution is setting `RESUME=none` in `/etc/initramfs-tools/conf.d` as described in https://askubuntu.com/questions/1029598/xubuntu-18-04-kernel-takes-long-to-boot

No problem with 16.04 though. Never been.

[Steve Langasek (vorlon)]

As I understand, you had an /etc/initramfs-tools/conf.d/resume file on your system that pointed to an invalid location. When was this file created? What were its contents? Do you know why the contents were invalid?

[Steve Langasek (vorlon)]

please also provide full dmesg output from a boot in which the problem has been reproduced.

[karlsebal (karlsebal)]

If I remember correctly resume was set to cryptswap partition. When doing so again (`RESUME=UUID=xxx`) invocation of `update-initramfs -uk all` gives

```
W: initramfs-tools configuration sets RESUME=UUID=9792e199-e275-4547-b9ce-c4e507e8bd5d
W: but no matching swap device is available.
```

The device is available and in use.

[karlsebal (karlsebal)]

If I remember correctly resume was set to cryptswap partition. When doing so again (`RESUME=UUID=xxx`) invocation of `update-initramfs -uk all` gives

```
W: initramfs-tools configuration sets RESUME=UUID=9792e199-e275-4547-b9ce-c4e507e8bd5d
W: but no matching swap device is available.
```

The device is available and in use. Dmesg output is attached

[Steve Langasek (vorlon)]

Thanks. What are the options for /dev/mapper/cryptsetup1 in /etc/crypttab? Is this a randomly-encrypted swap partition?

[karlsebal (karlsebal)]

Yes, it is randomly-encrypted:

cryptswap1 /dev/sda4 /dev/urandom swap,cipher=aes-cbc-essiv:sha256

On 07.06.2018 07:04, Steve Langasek wrote:
> Thanks. What are the options for /dev/mapper/cryptsetup1 in
> /etc/crypttab? Is this a randomly-encrypted swap partition?
>

[Steve Langasek (vorlon)]

Thanks. This will obviously never work for resume, since the encryption key is not saved anywhere across boot, so the scripts need to detect this case and avoid adding a resume setting in this case.

[Brian Murray (brian-murray)]

Hello Zwylicht, or anyone else affected,

Accepted initramfs-tools into bionic-proposed. The package will build now and be available at https://launchpad.net/ubuntu/+source/initramfs-tools/0.130ubuntu3.1 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-bionic to verification-done-bionic. If it does not fix the bug for you, please add a comment stating that, and change the tag to verification-failed-bionic. 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!

[Brian Murray (brian-murray)]

initramfs-tools (0.130ubuntu7) cosmic; urgency=medium

  * hooks/resume: don't generate RESUME config pointing to randomly-crypted
    swap devices. LP: #1771962.

[Steve Langasek (vorlon)]

I have run through the test case as described and confirmed that the updated initramfs-tools in bionic-proposed eliminates this 30-second wait in the initramfs. In my test VM, the rootfs is now mounted at 6.8s (and the swap is activated at 13.0s).

[Launchpad Janitor (janitor)]

This bug was fixed in the package initramfs-tools - 0.130ubuntu3.1

---------------
initramfs-tools (0.130ubuntu3.1) bionic; urgency=medium

  * hooks/resume: don't generate RESUME config pointing to randomly-crypted
    swap devices. LP: #1771962.

 -- Steve Langasek <email address hidden> Fri, 08 Jun 2018 21:29:19 -0700

[Łukasz Zemczak (sil2100)]

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.

[Tais P. Hansen (taisph)]

Note that this also applies if your swap is on ZFS. Ubuntu will attempt to use it automatically and cause a 30 second delay as the swap partition will not be available during early boot. Ie.

I: The initramfs will attempt to resume from /dev/zd0
I: (UUID=a0c4e220-8b9f-447b-b2e2-d2abeb2f6c39)
I: Set the RESUME variable to override this.

and

Aug 2 14:58:00 taisph-enodatio kernel: [ 3.822995] Btrfs loaded, crc32c=crc32c-intel
Aug 2 14:58:00 taisph-enodatio kernel: [ 35.038644] EXT4-fs (sda1): mounted filesystem with ordered data mode. Opts: (null)

Setting RESUME=none is currently necessary to work around this.

Tested with initramfs-tools 0.130ubuntu3.1.

[DiagonalArg (diagonalarg)]

I also applies when you have a swap partition and root is luks.