Re: [PATCH v5 3/3] arm64/fpsimd: Don't disable softirq when touching FPSIMD/SVE state

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On Tue, May 21, 2019 at 06:21:39PM +0100, Julien Grall wrote:
> Since a softirq is supposed to check may_use_simd() anyway before
> attempting to use FPSIMD/SVE, there is limited reason to keep softirq
> disabled when touching the FPSIMD/SVE context. Instead, we can simply
> disable preemption and mark the FPSIMD/SVE context as in use by setting
> CPU's fpsimd_context_busy flag.
[...]
> +static void get_cpu_fpsimd_context(void)
> +{
> +	preempt_disable();
> +	__get_cpu_fpsimd_context();
> +}

Is there anything that prevents a softirq being invoked between
preempt_disable() and __get_cpu_fpsimd_context()?

-- 
Catalin
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