Re: [PATCH] x86/microcode: Be more verbose, especially about loading errors

From: Jann Horn
Date: Wed Dec 06 2023 - 15:24:31 EST


On Wed, Dec 6, 2023 at 8:58 PM Borislav Petkov <bp@xxxxxxxxx> wrote:
> On Wed, Dec 06, 2023 at 06:28:44PM +0100, Jann Horn wrote:
> > The AMD ucode loader contains several checks for corrupted ucode blobs that
> > only log with pr_debug(); make them pr_err(), corrupted ucode blobs are
> > bad.
> >
> > Also make both microcode loaders a bit more verbose about whether they
> > found ucode blobs at all and whether they found ucode for the specific CPU.
>
> So far, so good.
>
> The only thing I'm missing here is the *why*.
>
> There's merit in not complaining about corrupted microcode blobs because
> they won't be loaded anyway: no harm, no foul.

Well, yes, except that if no microcode blob is loaded, you're not
gonna have the errata fixes and/or security mitigations that you might
expect to have.