This is a note to let you know that I've just added the patch titled tty: serial: 8250: Fix another runtime PM usage counter underflow to the 6.6-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: tty-serial-8250-fix-another-runtime-pm-usage-counter-underflow.patch and it can be found in the queue-6.6 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it.