Re: [PATCH] x86/msr: Block writes to certain MSRs unconditionally

[Andy Lutomirski]

> On Apr 11, 2021, at 9:43 AM, Andi Kleen <ak@xxxxxxxxxxxxxxx> wrote:
> 
> 
>> 
>> I have actually seen real user programs poke MSR_SYSCALL_MASK.
> 
> Hmm, what was the use case?
> 
> 

Working around a kernel bug.  The workaround only worked on AMD systems.  The correct solution was to fix the kernel bug, not poke MSRs.