Re: [PATCH 1/5] arm64: entry: isb in el1_irq

From: Mark Rutland
Date: Fri Apr 06 2018 - 13:35:03 EST


On Fri, Apr 06, 2018 at 06:30:50PM +0100, James Morse wrote:
> Hi Mark,
>
> On 06/04/18 18:22, Mark Rutland wrote:
> > Digging a bit, I also thing that our ct_user_exit and ct_user_enter
> > usage is on dodgy ground today.
>
> [...]
>
> > I think similar applies to SDEI; we don't negotiate with RCU prior to
> > invoking handlers, which might need RCU.
>
> The arch code's __sdei_handler() calls nmi_enter() -> rcu_nmi_enter(), which
> does a rcu_dynticks_eqs_exit().

Ah, sorry. I missed that!

Thanks,
Mark.