On Mon, Nov 30, 2020 at 01:00:03PM -0800, Guenter Roeck wrote: > On Fri, Nov 20, 2020 at 12:41:46PM +0100, Peter Zijlstra wrote: > > We call arch_cpu_idle() with RCU disabled, but then use > > local_irq_{en,dis}able(), which invokes tracing, which relies on RCU. > > > > Switch all arch_cpu_idle() implementations to use > > raw_local_irq_{en,dis}able() and carefully manage the > > lockdep,rcu,tracing state like we do in entry. > > > > (XXX: we really should change arch_cpu_idle() to not return with > > interrupts enabled) > > > > Has this patch been tested on s390 ? Reason for asking is that it causes > all my s390 emulations to crash. Reverting it fixes the problem. My understanding is that it changes the error on s390. Previously it would complain about the local_irq_enable() in arch_cpu_idle(), now it complains when taking an interrupt during idle.