Re: [PATCH v2 3/7] KVM: PPC: Fix mmio length message

On 07/01/2022 07:03, Fabiano Rosas wrote:
> We check against 'bytes' but print 'run->mmio.len' which at that point
> has an old value.
> 
> e.g. 16-byte load:
> 
> before:
> __kvmppc_handle_load: bad MMIO length: 8
> 
> now:
> __kvmppc_handle_load: bad MMIO length: 16
> 
> Signed-off-by: Fabiano Rosas <[email protected]>
> ---
>   arch/powerpc/kvm/powerpc.c | 4 ++--
>   1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/arch/powerpc/kvm/powerpc.c b/arch/powerpc/kvm/powerpc.c
> index 92e552ab5a77..0b0818d032e1 100644
> --- a/arch/powerpc/kvm/powerpc.c
> +++ b/arch/powerpc/kvm/powerpc.c
> @@ -1246,7 +1246,7 @@ static int __kvmppc_handle_load(struct kvm_vcpu *vcpu,
>   
>   	if (bytes > sizeof(run->mmio.data)) {
>   		printk(KERN_ERR "%s: bad MMIO length: %d\n", __func__,
> -		       run->mmio.len);
> +		       bytes);


"return EMULATE_FAIL;" here and below as there is really no point in 
trashing kvm_run::mmio (not much harm too but still) and this code does 
not handle more than 8 bytes anyway.



>   	}
>   
>   	run->mmio.phys_addr = vcpu->arch.paddr_accessed;
> @@ -1335,7 +1335,7 @@ int kvmppc_handle_store(struct kvm_vcpu *vcpu,
>   
>   	if (bytes > sizeof(run->mmio.data)) {
>   		printk(KERN_ERR "%s: bad MMIO length: %d\n", __func__,
> -		       run->mmio.len);
> +		       bytes);
>   	}
>   
>   	run->mmio.phys_addr = vcpu->arch.paddr_accessed;

-- 
Alexey