On Mon, Mar 22, 2021 at 12:12:49PM +0100, Johan Hovold wrote: > Force-threaded interrupt handlers used to run with interrupts enabled, > something which could lead to deadlocks in case a threaded handler > shared a lock with code running in hard interrupt context (e.g. timer > callbacks) and did not explicitly disable interrupts. > > Since commit 81e2073c175b ("genirq: Disable interrupts for force > threaded handlers") interrupt handlers always run with interrupts > disabled on non-RT so that drivers no longer need to do handle forced > threading ("threadirqs"). What happens on RT systems? Are they smart enough to avoid the whole problem by enabling interrupts during _all_ callbacks? Alan Stern