UEFI -l com1, stdio floods console/Windows Server SAC with "rdmsr to register 0x198 on vcpu..."

[Michael Dexter]

On 1/17/21 1:21 AM, Peter Grehan wrote:
>> Can the "rdmsr to register 0x198 on vcpu..." and similar messages on a 
>> -l com1,stdio console when using UEFI firmware be redirected or 
>> suppressed? The -w flag does not silence them, assuming, perhaps 
>> incorrectly, they are unsupported MSRs.
>>
>> If redirected, should these be logged?
> 
>   Please file a PR (https://www.freebsd.org/support/bugreports.html)
> 
>   A simple workaround is to use an nmdm or pty device for com1 output.

PR filed and indeed!

https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=252768

All the best,

Michael