Re: [PATCH RFC 0/5] x86/KVM/svm: get rid of hardcoded instructions lengths

From: Vitaly Kuznetsov
Date: Thu Jun 20 2019 - 08:31:45 EST


Paolo Bonzini <pbonzini@xxxxxxxxxx> writes:

> On 20/06/19 13:02, Vitaly Kuznetsov wrote:
>>
>> P.S. If you'd like to test the series you'll have to have a CPU without
>> NRIP_SAVE feature or forcefully disable it, something like:
>>
>> index 8d4e50428b68..93c7eaad7915 100644
>> --- a/arch/x86/kernel/cpu/amd.c
>> +++ b/arch/x86/kernel/cpu/amd.c
>> @@ -922,6 +922,9 @@ static void init_amd(struct cpuinfo_x86 *c)
>> /* AMD CPUs don't reset SS attributes on SYSRET, Xen does. */
>> if (!cpu_has(c, X86_FEATURE_XENPV))
>> set_cpu_bug(c, X86_BUG_SYSRET_SS_ATTRS);
>> +
>> + /* No nrips */
>> + clear_cpu_cap(c, X86_FEATURE_NRIPS);
>> }
>>
>> #ifdef CONFIG_X86_32
>
> Let's add a module parameter instead. Patch sent (forgot to Cc you).
>

Sure, I thought I'm the only interested person around but if there's
hope for more this definitely sounds like a good idea)

--
Vitaly