Re: IBM Power S822LC: pci 0021:0d:00.0: xHCI HW did not halt within 32000 usec status = 0x0

[Michal Pecio <michal.pecio@gmail.com>]

On Tue, 12 May 2026 08:17:08 +0200, Paul Menzel wrote:> 
> > I honestly don't know what to do with this. I think I would start with
> > looking whether xhci_shutdown() in the old kernel manages to halt it
> > successfully or if it also fails, and what's the USBSTS there.
> > 
> > It seems that you can get such information by enabling dynamic debug
> > 
> >    echo 'module xhci_hcd +p' >/proc/dynamic_debug/control
> > 
> > and capturing old kernel's log up to kexec() through a serial cable.  
> Unfortunately, nothing is logged over the serial console (BMC SOL) after 
> running `sudo kexec -e` or `sudo systemctl reboot`. I just see:
> 
>      [69530.180531343,5] OPAL: Switch to big-endian OS
>      [69538.407292205,5] OPAL: Switch to little-endian OS
> 
> Which is the OPAL firmware, so it might be involved? No idea, if it 
> touches the xHCI controller.

So some FW involvement is potentially possible.

BTW, another method of doing kexec is to setup a crash kernel and
then trigger panic with /proc/sysrq-trigger.

This probably won't run xhci_shutdown(). Not sure about OPAL FW.
Is the outcome any different?

> But strangely no xHCI messages are there –  also after booting with
> Petitboot and initialized xHCI controller? No idea, if it points to,
> that during kexec or shutdown nothing is power off?
> 
> With `sudo systemctl reboot` only the line below are logged:
>
>      [  121.811384] libvirt-guests.sh[3366]: Running guests on default URI:
>      [  121.811988] libvirt-guests.sh[3376]: no running guests.
>      [ … (systemd service stop notifications)]
>      [  136.254846] systemd-shutdown[1]: Waiting for process: watch_ldconfig
>      [  218.549684] reboot: Restarting system
>      [69760.484679183,5] OPAL: Reboot request...
>        3.55778|Ignoring boot flags, incorrect version 0x0
>        3.59881|ISTEP  6. 3

Only "reboot: Restarting system" looks like it's kernel. Maybe you need
to tweak loglevel before rebooting or kexecing? Try to get more kernel
messages showing over serial during operation, then kexec.

Regards,
Michal