On Wed, Feb 12, 2020 at 10:32:10AM +0100, Peter Zijlstra wrote: > Hi all, > > These here patches are the result of Mathieu and Steve trying to get commit > 865e63b04e9b2 ("tracing: Add back in rcu_irq_enter/exit_irqson() for rcuidle > tracepoints") reverted again. > > One of the things discovered is that tracing MUST NOT happen before nmi_enter() > or after nmi_exit(). I've only fixed x86, but quickly gone through other > architectures and there is definitely more stuff to be fixed (simply grep for > nmi_enter in your arch). For ARM64: - apei_claim_sea() - __sdei_handler() - do_serror() - debug_exception_enter() / do_debug_exception() all look dodgy.