Re: [PATCH v7 01/12] xen/vmx: let opt_ept_ad always reflect the current setting

[Jan Beulich <jbeulich@xxxxxxxx>]

On 02.04.2020 17:46, Juergen Gross wrote:
> In case opt_ept_ad has not been set explicitly by the user via command
> line or runtime parameter, it is treated as "no" on Avoton cpus.
> 
> Change that handling by setting opt_ept_ad to 0 for this cpu type
> explicitly if no user value has been set.
> 
> By putting this into the (renamed) boot time initialization of vmcs.c
> _vmx_cpu_up() can be made static.
> 
> Signed-off-by: Juergen Gross <jgross@xxxxxxxx>

Reviewed-by: Jan Beulich <jbeulich@xxxxxxxx>
albeit preferably with ...

> @@ -2108,9 +2104,21 @@ static void vmcs_dump(unsigned char ch)
>      printk("**************************************\n");
>  }
>  
> -void __init setup_vmcs_dump(void)
> +int __init vmx_vmcs_init(void)
>  {
> -    register_keyhandler('v', vmcs_dump, "dump VT-x VMCSs", 1);
> +    int ret;
> +
> +    if ( opt_ept_ad < 0 )
> +        /* Work around Erratum AVR41 on Avoton processors. */
> +        opt_ept_ad = (boot_cpu_data.x86 == 6 &&
> +                      boot_cpu_data.x86_model == 0x4d) ? 0 : 1;

... no use of the conditional operator here - the result of the
&& (or its logical inversion to be precise) would be quite fine
to use directly here.

Jan