From mboxrd@z Thu Jan  1 00:00:00 1970
From: Marc Zyngier <marc.zyngier@arm.com>
Subject: Re: [PATCH 26/31] KVM: arm64: vgic-v3: Add ICV_DIR_EL1 handler
Date: Tue, 30 May 2017 15:45:07 +0100
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References: <20170503104606.19342-1-marc.zyngier@arm.com>
 <20170503104606.19342-27-marc.zyngier@arm.com>
 <6c34b576-a0d2-6e7d-b363-349a5319dcf6@redhat.com>
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Cc: Mark Rutland <mark.rutland@arm.com>, kvm@vger.kernel.org,
        David Daney <david.daney@cavium.com>,
        Catalin Marinas <catalin.marinas@arm.com>,
        Robert Richter <rrichter@cavium.com>,
        kvmarm@lists.cs.columbia.edu, linux-arm-kernel@lists.infradead.org
To: Auger Eric <eric.auger@redhat.com>,
        Christoffer Dall <christoffer.dall@linaro.org>
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On 30/05/17 11:15, Auger Eric wrote:
> Marc,
> 
> On 03/05/2017 12:46, Marc Zyngier wrote:
>> Add a handler for writing the guest's view of the ICC_DIR_EL1
>> register, performing the deactivation of an interrupt if EOImode
>> is set ot 1.
>>
>> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
>> ---
>>  virt/kvm/arm/hyp/vgic-v3-sr.c | 23 +++++++++++++++++++++++
>>  1 file changed, 23 insertions(+)
>>
>> diff --git a/virt/kvm/arm/hyp/vgic-v3-sr.c b/virt/kvm/arm/hyp/vgic-v3-sr.c
>> index 9c639f57268b..563dd2d16c59 100644
>> --- a/virt/kvm/arm/hyp/vgic-v3-sr.c
>> +++ b/virt/kvm/arm/hyp/vgic-v3-sr.c
>> @@ -612,6 +612,26 @@ static void __hyp_text __vgic_v3_bump_eoicount(void)
>>  	write_gicreg(hcr, ICH_HCR_EL2);
>>  }
>>  
>> +static void __hyp_text __vgic_v3_write_dir(struct kvm_vcpu *vcpu,
>> +					   u32 vmcr, int rt)
>> +{
>> +	u32 vid = vcpu_get_reg(vcpu, rt);
>> +	u64 lr_val;
>> +	int lr;
>> +
>> +	/* No deactivate to be performed on an LPI */
>> +	if (vid >= VGIC_MIN_LPI)
>> +		return;
> 
> don't you need to test the EOImode first? Spec says:
> "
> When EOImode == ‘0’. GICv3 implementations must ignore such writes. In
> systems supporting system error generation, an implementation might
> generate an SEI.
> "

Ah, very good point! Thanks for the heads up!

	M.
-- 
Jazz is not dead. It just smells funny...