Ubuntu
linux package

lunar/linux 6.2 fails to boot on arm64

Bug #2011748 reported by Andrea Righi
6
This bug affects 1 person
Affects Status Importance Assigned to Milestone
linux (Ubuntu)
Fix Released
Undecided
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Lunar
Fix Released
Undecided
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Bug Description

[Impact]

On certain bare metal arm64 boards the latest lunar/linux 6.2.0-17-generic fails to boot, the kernel gets stuck reporting the following oops:

[ 72.043484] rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
[ 72.049571] rcu: 22-...0: (30 GPs behind) idle=b10c/1/0x4000000000000000 softirq=164/164 fqs=6443
[ 72.058520] (detected by 28, t=15005 jiffies, g=449, q=174 ncpus=32)
[ 72.064949] Task dump for CPU 22:
[ 72.068251] task:kworker/u64:5 state:R running task stack:0 pid:447 ppid:2 flags:0x0000000a
[ 72.078156] Workqueue: efi_rts_wq efi_call_rts
[ 72.082595] Call trace:
[ 72.085029] __switch_to+0xbc/0x100

The bug doesn't seem to happen on arm64 virtual machines, it happens only on physical arm64 systems.

This regression has been introduced by:

e7b813b32a42 ("efi: random: refresh non-volatile random seed when RNG is initialized")

[Test case]

Boot the kernel on a physical arm64 board (i.e., kuzzle in our lab).

[Fix]

Revert commit e7b813b32a42 for now, at the same time address this issue upstream in order to find a proper fix.

[Regression potential]

We may want to address this upstream to find a proper fix. Reverting the commit restores the previous behavior, but we also lose the capability of having a better RNG on the affected arm64 hardware.

See original description
Revision history for this message
Ubuntu Kernel Bot (ubuntu-kernel-bot) wrote : Missing required logs.

This bug is missing log files that will aid in diagnosing the problem. While running an Ubuntu kernel (not a mainline or third-party kernel) please enter the following command in a terminal window:

apport-collect 2011748

and then change the status of the bug to 'Confirmed'.

If, due to the nature of the issue you have encountered, you are unable to run this command, please add a comment stating that fact and change the bug status to 'Confirmed'.

This change has been made by an automated script, maintained by the Ubuntu Kernel Team.

Changed in linux (Ubuntu):
status: New → Incomplete
Andrea Righi (arighi)
description: updated
Andrea Righi (arighi)
Changed in linux (Ubuntu Lunar):
status: Incomplete → Fix Committed
Revision history for this message
Launchpad Janitor (janitor) wrote :

This bug was fixed in the package linux - 6.2.0-18.18

---------------
linux (6.2.0-18.18) lunar; urgency=medium

  * lunar/linux: 6.2.0-18.18 -proposed tracker (LP: #2011750)

  * lunar/linux 6.2 fails to boot on arm64 (LP: #2011748)
    - SAUCE: Revert "efi: random: fix NULL-deref when refreshing seed"
    - SAUCE: Revert "efi: random: refresh non-volatile random seed when RNG is
      initialized"

 -- Andrea Righi <email address hidden> Wed, 15 Mar 2023 23:54:18 +0100

Changed in linux (Ubuntu Lunar):
status: Fix Committed → Fix Released
Revision history for this message
Ubuntu Kernel Bot (ubuntu-kernel-bot) wrote :

This bug is awaiting verification that the linux-azure/6.2.0-1009.9 kernel in -proposed solves the problem. Please test the kernel and update this bug with the results. If the problem is solved, change the tag 'verification-needed-lunar' to 'verification-done-lunar'. If the problem still exists, change the tag 'verification-needed-lunar' to 'verification-failed-lunar'.

If verification is not done by 5 working days from today, this fix will be dropped from the source code, and this bug will be closed.

See https://wiki.ubuntu.com/Testing/EnableProposed for documentation how to enable and use -proposed. Thank you!

tags: added: kernel-spammed-lunar-linux-azure verification-needed-lunar
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