[PATCH v3 05/14] ARM: KVM: vgic mmio should hold data as LE bytes array in BE case

Marc Zyngier marc.zyngier at arm.com
Tue May 27 08:07:50 PDT 2014


On 13/05/14 17:13, Victor Kamensky wrote:
> According to recent clarifications of mmio.data array meaning -
> the mmio.data array should hold bytes as they would appear in
> memory. Vgic is little endian device. And in case of BE image
> kernel side that emulates vgic, holds data in BE form. So we
> need to byteswap cpu<->le32 vgic registers when we read/write them
> from mmio.data[].
> 
> Change has no effect in LE case because cpu already runs in le32.
> 
> Signed-off-by: Victor Kamensky <victor.kamensky at linaro.org>
> Reviewed-by: Christoffer Dall <christoffer.dall at linaro.org>
> ---
>  virt/kvm/arm/vgic.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/virt/kvm/arm/vgic.c b/virt/kvm/arm/vgic.c
> index 56ff9be..529c336 100644
> --- a/virt/kvm/arm/vgic.c
> +++ b/virt/kvm/arm/vgic.c
> @@ -241,12 +241,12 @@ static void vgic_cpu_irq_clear(struct kvm_vcpu *vcpu, int irq)
>  
>  static u32 mmio_data_read(struct kvm_exit_mmio *mmio, u32 mask)
>  {
> -	return *((u32 *)mmio->data) & mask;
> +	return le32_to_cpu(*((u32 *)mmio->data)) & mask;
>  }
>  
>  static void mmio_data_write(struct kvm_exit_mmio *mmio, u32 mask, u32 value)
>  {
> -	*((u32 *)mmio->data) = value & mask;
> +	*((u32 *)mmio->data) = cpu_to_le32(value) & mask;
>  }
>  
>  /**
> 

Acked-by: Marc Zyngier <marc.zyngier at arm.com>

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



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