[PATCH 2/8] KVM: arm64: Remove leftover kern_hyp_va() in nVHE TLB invalidation

[Alexandru Elisei]

Hi Marc,

On 10/26/20 9:51 AM, Marc Zyngier wrote:
> The new calling convention says that pointers coming from the SMCCC
> interface are turned into their HYP version in the host HVC handler.
> However, there is still a stray kern_hyp_va() in the TLB invalidation
> code, which could result in a corrupted pointer.
>
> Drop the spurious conversion.
>
> Fixes: a071261d9318 ("KVM: arm64: nVHE: Fix pointers during SMCCC convertion")
> Signed-off-by: Marc Zyngier <maz at kernel.org>
> ---
>  arch/arm64/kvm/hyp/nvhe/tlb.c | 1 -
>  1 file changed, 1 deletion(-)
>
> diff --git a/arch/arm64/kvm/hyp/nvhe/tlb.c b/arch/arm64/kvm/hyp/nvhe/tlb.c
> index 39ca71ab8866..fbde89a2c6e8 100644
> --- a/arch/arm64/kvm/hyp/nvhe/tlb.c
> +++ b/arch/arm64/kvm/hyp/nvhe/tlb.c
> @@ -128,7 +128,6 @@ void __kvm_tlb_flush_local_vmid(struct kvm_s2_mmu *mmu)
>  	struct tlb_inv_context cxt;
>  
>  	/* Switch to requested VMID */
> -	mmu = kern_hyp_va(mmu);
>  	__tlb_switch_to_guest(mmu, &cxt);
>  
>  	__tlbi(vmalle1);

Looks fine to me, the function handle_host_hcall() already does the required
transformation when handling the __kvm_tlb_flush_local_vmid function id:

case KVM_HOST_SMCCC_FUNC(__kvm_tlb_flush_local_vmid): { unsigned long r1 =
host_ctxt->regs.regs[1]; struct kvm_s2_mmu *mmu = (struct kvm_s2_mmu *)r1;
__kvm_tlb_flush_local_vmid(kern_hyp_va(mmu)); break; }

Reviewed-by: Alexandru Elisei <alexandru.elisei at arm.com>