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Subject: Re: [PATCH 1/5] arm64: entry: isb in el1_irq
To: Mark Rutland <mark.rutland@arm.com>
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From: James Morse <james.morse@arm.com>
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Date: Fri, 6 Apr 2018 18:30:50 +0100
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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().


Thanks,

James