[PATCH 2/5] ARM: KVM: add missing dsb before invalidating Stage-2 TLBs

[Will Deacon]

On Wed, Jun 19, 2013 at 02:20:03PM +0100, Marc Zyngier wrote:
> When performing a Stage-2 TLB invalidation, it is necessary to
> make sure the write to the page tables is observable by all CPUs.
> 
> For this purpose, add a dsb instruction to __kvm_tlb_flush_vmid_ipa
> before doing the TLB invalidation itself.
> 
> Signed-off-by: Marc Zyngier <marc.zyngier at arm.com>
> ---
>  arch/arm/kvm/interrupts.S | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/arch/arm/kvm/interrupts.S b/arch/arm/kvm/interrupts.S
> index d0a8fa3..afa6c04 100644
> --- a/arch/arm/kvm/interrupts.S
> +++ b/arch/arm/kvm/interrupts.S
> @@ -49,6 +49,7 @@ __kvm_hyp_code_start:
>  ENTRY(__kvm_tlb_flush_vmid_ipa)
>  	push	{r2, r3}
>  
> +	dsb

This can be dsb	ish.

Will