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Date:   Mon, 23 Nov 2020 14:32:20 +0000
Message-ID: <87k0uc5ekr.wl-maz@kernel.org>
From:   Marc Zyngier <maz@kernel.org>
To:     David Brazdil <dbrazdil@google.com>
Cc:     kvmarm@lists.cs.columbia.edu, linux-arm-kernel@lists.infradead.org,
        linux-kernel@vger.kernel.org, James Morse <james.morse@arm.com>,
        Julien Thierry <julien.thierry.kdev@gmail.com>,
        Suzuki K Poulose <suzuki.poulose@arm.com>,
        Catalin Marinas <catalin.marinas@arm.com>,
        Will Deacon <will@kernel.org>, Dennis Zhou <dennis@kernel.org>,
        Tejun Heo <tj@kernel.org>, Christoph Lameter <cl@linux.com>,
        Mark Rutland <mark.rutland@arm.com>,
        Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>,
        Quentin Perret <qperret@google.com>,
        Andrew Scull <ascull@google.com>,
        Andrew Walbran <qwandor@google.com>, kernel-team@android.com
Subject: Re: [PATCH v2 07/24] kvm: arm64: Refactor handle_trap to use a switch
In-Reply-To: <20201116204318.63987-8-dbrazdil@google.com>
References: <20201116204318.63987-1-dbrazdil@google.com>
        <20201116204318.63987-8-dbrazdil@google.com>
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On Mon, 16 Nov 2020 20:43:01 +0000,
David Brazdil <dbrazdil@google.com> wrote:
> 
> Small refactor so that nVHE's handle_trap uses a switch on the Exception
> Class value of ESR_EL2 in preparation for adding a handler of SMC32/64.

nit: SMC32 seems to be a leftover from the previous version.

>
> Signed-off-by: David Brazdil <dbrazdil@google.com>
> ---
>  arch/arm64/kvm/hyp/nvhe/hyp-main.c | 15 ++++++++-------
>  1 file changed, 8 insertions(+), 7 deletions(-)
> 
> diff --git a/arch/arm64/kvm/hyp/nvhe/hyp-main.c b/arch/arm64/kvm/hyp/nvhe/hyp-main.c
> index 411b0f652417..19332c20fcde 100644
> --- a/arch/arm64/kvm/hyp/nvhe/hyp-main.c
> +++ b/arch/arm64/kvm/hyp/nvhe/hyp-main.c
> @@ -16,9 +16,9 @@
>  
>  DEFINE_PER_CPU(struct kvm_nvhe_init_params, kvm_init_params);
>  
> -static void handle_host_hcall(unsigned long func_id,
> -			      struct kvm_cpu_context *host_ctxt)
> +static void handle_host_hcall(struct kvm_cpu_context *host_ctxt)
>  {
> +	unsigned long func_id = host_ctxt->regs.regs[0];
>  	unsigned long ret = 0;
>  
>  	switch (func_id) {
> @@ -109,11 +109,12 @@ static void handle_host_hcall(unsigned long func_id,
>  void handle_trap(struct kvm_cpu_context *host_ctxt)
>  {
>  	u64 esr = read_sysreg_el2(SYS_ESR);
> -	unsigned long func_id;
>  
> -	if (ESR_ELx_EC(esr) != ESR_ELx_EC_HVC64)
> +	switch (ESR_ELx_EC(esr)) {
> +	case ESR_ELx_EC_HVC64:
> +		handle_host_hcall(host_ctxt);
> +		break;
> +	default:
>  		hyp_panic();
> -
> -	func_id = host_ctxt->regs.regs[0];
> -	handle_host_hcall(func_id, host_ctxt);
> +	}
>  }
> -- 
> 2.29.2.299.gdc1121823c-goog
> 
> 

Thanks,

	M.

-- 
Without deviation from the norm, progress is not possible.