Re: [Bug 219906] New: Kernel Oops in pcie_update_link_speed when hotplugging TB4 dock on x870e / kernel 6.14.0-rc7

[Bjorn Helgaas <helgaas@kernel.org>]

On Fri, Mar 21, 2025 at 06:30:40PM +0000, bugzilla-daemon@kernel.org wrote:
> https://bugzilla.kernel.org/show_bug.cgi?id=219906
> 
>             Bug ID: 219906
>            Summary: Kernel Oops in pcie_update_link_speed when hotplugging
>                     TB4 dock on x870e / kernel 6.14.0-rc7

> Created attachment 307878
>   --> https://bugzilla.kernel.org/attachment.cgi?id=307878&action=edit
> dmesg output hotplugging dock
> 
> When connecting a Lenovo TB4 dock (40B0) using the USB4 port of an ASRock x870E
> Nova motherboard, Linux kernel 6.14.0-rc7 will Oops with a NULL pointer
> dereference. 
> 
> This is 100% reproducible on my system and happens immediately when plugging
> the USB4 cable into the docking station. Interestingly, USB devices connected
> to the docking station still work, but displays connected to it will not. Also,
> after the kernel Oops the system is in some corrupted state, as things like
> mkinitcpio will hang at the autodetect hook when enumerating udev devices, and
> when shutting down the system will get stuck indefinitely on hanging
> udev_worker processes.
> 
> When booting the machine while the dock is already attached, the kernel boots
> without any apparent problems, but displays connected to the dock will still
> not show any image. 
> 
> This dock has been working without any issue in combination with a different
> Linux laptop with USB4 and an AMD780M, a MacBook Pro, and a Windows 11 laptop.
> 
> Attached is the dmesg output after hot-plugging the dock.

Do you know whether this is a regression?  Does any kernel work
correctly on the system in question?