Re: [RFC][PATCH] x86/cpu/bugs: Consider having old Intel microcode to be a vulnerability

[Dave Hansen <dave.hansen@intel.com>]

On 11/19/24 09:45, Pawan Gupta wrote:
> Sorry for playing the devil's advocate. I am wondering who is the prime
> beneficiary of this change?

At a very high level, it's for folks with new kernels and old microcode.

It's _very_ normal for someone to report a bug and for us upstream folks
to ask them to reproduce on the latest mainline. The moment they do
that, they get the latest microcode list. Folks don't randomly upgrade
to a new kernel for fun in production. But it's hopefully a very normal
activity for folks having problems and launching into debug.

In other words, "new kernel / old microcode" might be relatively rare,
but it still gets used at a *very* critical choke point.

I completely agree with your general sentiment that normal distro users
will get the distro-kernel-provided microcode version list _and_
distro-provided microcode files. This won't help them one bit unless the
distro makes a silly mistake, doesn't do testing, or they somehow
upgrade one package without the other.