Re: [PATCH 0/2] KVM: x86: Propagate AMD-specific IBRS bits to guests

From: Borislav Petkov
Date: Tue Feb 28 2023 - 15:46:06 EST


On Tue, Feb 28, 2023 at 07:41:53PM +0000, Takahiro Itazuri wrote:
> It is true that the kernel does not use those bits at all, but any
> codes could be run inside guests.

So you mean we should stick *all* CPUID leafs in there just because
anything can run in guests?

What is the hypervisor then for?

> One of examples is the following spectre/meltdown checker scipt used as
> de facto standard.

Really? Says who?

$ grep -r . /sys/devices/system/cpu/vulnerabilities/

gives you all you need to know.

And if something's missing, then I'm listening.

Thx.

--
Regards/Gruss,
Boris.

https://people.kernel.org/tglx/notes-about-netiquette