On 25.07.2023 08:40, Jan Beulich wrote:
> On 24.07.2023 18:52, Alejandro Vallejo wrote:
>> --- a/xen/arch/x86/cpu/microcode/core.c
>> +++ b/xen/arch/x86/cpu/microcode/core.c
>> @@ -867,10 +867,23 @@ int __init early_microcode_init(unsigned long
>> *module_map,
>> return -ENODEV;
>> }
>>
>> - microcode_grab_module(module_map, mbi);
>> -
>> ucode_ops.collect_cpu_info();
>>
>> + /*
>> + * Some hypervisors deliberately report a microcode revision of -1 to
>> + * mean that they will not accept microcode updates. We take the hint
>> + * and ignore the microcode interface in that case.
>> + */
>> + if ( this_cpu(cpu_sig).rev == ~0 )
>> + {
>> + printk(XENLOG_INFO "Microcode loading disabled due to: %s",
>
> While we have tentatively agreed to adjust what _will_ be emitted by
> default (subject to suitable justification in that change's
> description), such a patch is yet to be sent. As it stands this message
> will be invisible by default.
>
>> + "HW toggle");
>
> With the comment talking about hypervisors, what is this string supposed
> to tell an observer of the message in a log file?
Looking at patch 3 I get the impression that you put here the wrong of the
two messages there.
Jan
