This bug is missing log files that will aid in diagnosing the problem.
From a terminal window please run:

apport-collect 2099935

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 and change the
bug status to 'Confirmed'.

-- 
You received this bug notification because you are a member of Kernel
Packages, which is subscribed to linux in Ubuntu.
https://bugs.launchpad.net/bugs/2099935

Title:
  PCI initialization failure following kernel panic reboot on Raspberry
  Pi CM4

Status in linux package in Ubuntu:
  New

Bug description:
  Ubuntu Server 24.10 
  Linux ubuntu 6.11.0-1004-raspi #4-Ubuntu SMP PREEMPT_DYNAMIC Fri Sep 27 
22:25:34 UTC 2024 aarch64 aarch64 aarch64 GNU/Linux

  We're seeing that following a kernel panic and reboot, the PCI fails
  to initialize correctly and associated  devices (such as Wi-Fi card)
  are not available.

  Issue Description:
  •     On the first boot, everything works correctly.
  •     However, after a Kernel Panic, the device reboots, but PCIe does not 
reset or re-initialize properly.
  •     When this happens:
  o     The Wi-Fi card is not recognized.
  o     The lspci command shows no PCI devices.
  o     The dmesg log includes the message:

  [    0.591441] brcm-pcie fd500000.pcie: link down

  •     A soft reboot does not fix the issue.
  •     The only way to recover is to completely remove and reconnect power 
(hard reboot).

  
  We have tried modifying /boot/firmware/config.txt and 
/boot/firmware/cmdline.txt, which has reduced but not fully resolved the issue.

  How to Reproduce The Problem:
  1.    Power up the hardware
  2.    Run ‘lspci’ – observe the result includes the PCI Bridge and Wi-Fi card
  3.    Trigger a kernel panic with the command ‘echo c | sudo tee 
/proc/sysrq-trigger’, causing a reboot
  4.    Run ‘lspci’ – observer the output is now empty

  
  The same issue does not occur on Raspberry Pi OS - it seems to be specific to 
Ubuntu.

  Any assistance/guidance on how to troubleshoot this would be much
  appreciated!

To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu/+source/linux/+bug/2099935/+subscriptions


-- 
Mailing list: https://launchpad.net/~kernel-packages
Post to     : kernel-packages@lists.launchpad.net
Unsubscribe : https://launchpad.net/~kernel-packages
More help   : https://help.launchpad.net/ListHelp

Reply via email to