Bug#1151916: linux: xhci AMD Renoir [1022:1639] USB hotplug detection broken after boot on 6.12.113

[Salvatore Bonaccorso]

Control: tags -1 + moreinfo upstream

Hi,

On Sat, Oct 24, 2026 at 02:47:14PM +0200, youl wrote:
> Source: linux
> Version: 6.12.113-1
> Severity: important
> X-Debbugs-Cc: y...@murena.io
> 
> Dear Maintainer,
> 
> --- Details ---
> A regression has been introduced in kernel version 6.12.113
> affecting the AMD Renoir xHCI USB controllers [1022:1639]. USB
> hotplug detection completely breaks after boot, though all devices
> connected at boot enumerate successfully.

As you are experiencing the regression from 6.12.107-1 can you please
bisect the changes upstream and report back what is the causing
change.

    git clone --single-branch -b linux-6.12.y 
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable.git
    cd linux-stable
    git checkout v6.12.107
    cp /boot/config-$(uname -r) .config
    yes '' | make localmodconfig
    make savedefconfig
    mv defconfig arch/x86/configs/my_defconfig

    # test 6.12.107 to ensure this is "good"
    make my_defconfig
    make -j $(nproc) bindeb-pkg
    ... install the resulting .deb package and confirm problem does not exist

    # test 6.12.113 to ensure this is "bad"
    git checkout v6.12.113
    make my_defconfig
    make -j $(nproc) bindeb-pkg
    ... install the resulting .deb package and confirm problem exists

With that confirmed, the bisection can start:

    git bisect start --first-parent
    git bisect good v6.12.107
    git bisect bad v6.12.113

In each bisection step git checks out a state between the oldest
known-bad and the newest known-good commit. In each step test using:

    make my_defconfig
    make -j $(nproc) bindeb-pkg
    ... install, verify if problem exists

and if the problem is hit run:

    git bisect bad

and if the problem doesn't trigger run:

    git bisect good

. Please pay attention to always select the just built kernel for
booting, it won't always be the default kernel picked up by grub.

Iterate until git announces to have identified the first bad commit.

Then provide the output of

    git bisect log

In the course of the bisection you might have to uninstall previous
kernels again to not exhaust the disk space in /boot. Also in the end
uninstall all self-built kernels again.

Regards,
Salvatore