Ahead of today's beta release of the Linux 6.6-rc6 kernel, a rather embarrassing bug surfaced this week as part of a fix for the HID subsystem: for the past few months, unplugging a Logitech USB receiver would cause the Linux kernel to crash.
There have been numerous bug reports surrounding this issue, ranging from unplugging Logitech keyboard/mouse receivers to simply turning off the USB switch to which the device is connected, and the Linux 6.6-rc6 kernel has been fixed and marked as a backport to the existing stable Linux kernel series.
Red Hat's Hans de Goede continues to work wonders fixing and improving Linux desktop/laptop hardware support. He was responsible for fixing a bug where Logitech USB receivers were disconnecting. This follows a series of different bug reports released by Red Hat over the summer: USB disconnect causing kernel crash, power_supply_uevent on USB causing page_fault_oops, kernel module hid_logitech_dj causing crash and USB corruption, Logitech unify receiver not working properly, and more.
As explained in the patch to fix a kernel crash when the receiver USB is disconnected, there are four check-time vs. usage time races that need to be resolved.
The fix has been merged as part of this week's Linux6.6-rc6HID fixes and will be backported to the Linux stable series in the coming days. During this period, if you are using the latest Linux kernel version, please do not unplug the Logitech USB receiver in the boot environment to avoid kernel crashes.