Re: [PATCH v2 3/4] x86/cpuid: Introduce dom0-cpuid command line option

[Andrew Cooper <amc96@srcf.net>]

On 15/12/2021 22:21, Andrew Cooper wrote:
> diff --git a/xen/arch/x86/cpuid.c b/xen/arch/x86/cpuid.c
> index e11f5a3c9a6b..83a80ba6de70 100644
> --- a/xen/arch/x86/cpuid.c
> +++ b/xen/arch/x86/cpuid.c
> @@ -116,6 +116,23 @@ static int __init parse_xen_cpuid(const char *s)
>  }
>  custom_param("cpuid", parse_xen_cpuid);
>  
> +static bool __initdata dom0_cpuid_cmdline;
> +static uint32_t __initdata dom0_enable_feat[FSCAPINTS];
> +static uint32_t __initdata dom0_disable_feat[FSCAPINTS];
> +
> +static void __init _parse_dom0_cpuid(unsigned int feat, bool val)
> +{
> +    __set_bit(feat, val ? dom0_enable_feat : dom0_disable_feat);

Based on Jan's observation in v1, I've folded this delta in:

diff --git a/xen/arch/x86/cpuid.c b/xen/arch/x86/cpuid.c
index 83a80ba6de70..39baeae9a6cd 100644
--- a/xen/arch/x86/cpuid.c
+++ b/xen/arch/x86/cpuid.c
@@ -122,7 +122,8 @@ static uint32_t __initdata dom0_disable_feat[FSCAPINTS];
 
 static void __init _parse_dom0_cpuid(unsigned int feat, bool val)
 {
-    __set_bit(feat, val ? dom0_enable_feat : dom0_disable_feat);
+    __set_bit  (feat, val ? dom0_enable_feat  : dom0_disable_feat);
+    __clear_bit(feat, val ? dom0_disable_feat : dom0_enable_feat );
 }
 
 static int __init parse_dom0_cpuid(const char *s)

~Andrew