CVE-2026-80548

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> s390/vfio_ccw: Selectively expand io_mutex<br /> <br /> The io_mutex was defined to serialize the io_regions, but then has<br /> also sort of been associated with the I/O themselves because of<br /> the close relationship they share.<br /> <br /> With the handful of races that are possible, the choices are either to:<br /> A) expand the scope of io_mutex to close these remaining windows, or<br /> B) reduce the scope of io_mutex to just io_region, and introduce a new<br /> lock mechanism for the remaining I/O resources<br /> <br /> This patch implements A, since B brings with it a lot more interactions<br /> that would need to be tracked and kept in a correct hierarchy. It also<br /> takes advantage of the workqueue element for cp_free() that now gets<br /> called out of fsm_notoper(), which could be invoked out of an interrupt<br /> context and thus cannot acquire a mutex itself.