Re: [PATCH] x86/microcode: Add an option to reload microcode even if revision is unchanged

[Borislav Petkov]

On Tue, Sep 17, 2019 at 08:37:10AM +0200, Thomas Gleixner wrote:
> So what happens if the ucode update "fixes" one of the executed
> instructions on the fly? Is that guaranteed to be safe? There is nothing
> which says so.

You'd expect that when you load microcode on the core, the one thread
does the loading and the other SMT thread is in a holding pattern. That
would be optimal.

Considering the dancing through hoops we're doing to keep all threads
quiesced, I'd be sceptical that is the case...

-- 
Regards/Gruss,
    Boris.

ECO tip #101: Trim your mails when you reply.
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