Re: [Bug 221721] New: prom21-xhci does not allow to use USB keyboard in plymouth

With a little more of thinking, I think this happens due to the
initramfs building tool not including xhci-pci-prom21.ko when
xhci-pci.ko is built with the Kconfig where USB_XHCI_PCI_PROM21 was enabled.

Can you check your initramfs file for whether it holds
xhci-pci-prom21.ko correctly, or not?

For example, with dracut, you can do something like:
cat <<'EOF' | sudo tee /etc/dracut.conf.d/10-xhci-pci-prom21.conf
# PROM21 xHCI PCI glue is needed before root/LUKS unlock when xhci-pci
is modular.
force_drivers+=" xhci-pci-prom21 "
EOF


Sincerely,
Jihong Min


On 7/7/26 17:03, Thorsten Leemhuis wrote:
> [Switching to email, hope this will work]
> 
> Jihong Min, it seems a recent change of yours is causing trouble. See
> below for details.
> 
> Side note, but not my area of expertise, so feel free to ignore this, as
> I might be sending people in the wrong direction and it's just a hunch
> anyway: wonder if this is another of those situations where the driver
> needs to be in the initramfs. Tomasz, did you have SENSORS_PROM21_XHCI=m
> when things were broken? And if yes: have you tried if adding it to the
> initramfs or setting SENSORS_PROM21_XHCI=y helps?
> 
> Ciao, Thorsten
> 
> On 7/4/26 17:41, [email protected] wrote:
>> https://bugzilla.kernel.org/show_bug.cgi?id=221721
>>
>>             Bug ID: 221721
>>            Summary: prom21-xhci does not allow to use USB keyboard in
>>                     plymouth
>>            Product: Drivers
>>            Version: 2.5
>>           Hardware: AMD
>>                 OS: Linux
>>             Status: NEW
>>           Severity: low
>>           Priority: P3
>>          Component: USB
>>           Assignee: [email protected]
>>           Reporter: [email protected]
>>         Regression: No
>>
>> Created attachment 310416
>>   --> https://bugzilla.kernel.org/attachment.cgi?id=310416&action=edit
>> output of "sudo lsusb -v"
>>
>> Hi,
>>
>> After update to 7.2-rc1 I was unable to type in LUKS password in plymouth. I
>> tried both of my USB keyboards, but both of them just briefly lit up the LEDs
>> and then seemed to turn off. Bisection pointed to
>>
>> commit 364f4a55c661641c02c86a849f0608d8fc3c0006
>> Merge: e4b4bfaa5090 1c2b66a7d725
>> Author: Linus Torvalds <[email protected]>
>> Date:   Mon Jun 22 12:09:47 2026 -0700
>>
>>     Merge tag 'usb-7.2-rc1' of
>> git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb
>>
>> and then
>>
>> commit 9e896b4a48c4e815956d28961448041c80ad5a19 (HEAD)
>> Author: Jihong Min <[email protected]>
>> Date:   Tue May 19 09:07:31 2026 +0900
>>
>>     usb: xhci-pci: add AMD Promontory 21 PCI glue
>>
>> After setting SENSORS_PROM21_XHCI=n and compiling kernel again, I'm able to use
>> my PC normally.
>>
>> CPU: AMD Ryzen 9 9900X
>> Motherboard: X870I AORUS PRO ICE
>> Output of "lsusb -v" provided in attachment.
>>
>