Re: [tip: x86/bugs] x86/retpoline: Ensure default return thunk isn't used at runtime

From: Borislav Petkov
Date: Wed Oct 18 2023 - 11:13:08 EST


On Wed, Oct 18, 2023 at 03:38:56PM +0200, Ingo Molnar wrote:
> If then WARN_ONCE().

WARN_ONCE() is not enough considering that if this fires, it means we're
not really properly protected against one of those RET-speculation
things.

It needs to be warning constantly but then still allow booting. I.e,
a ratelimited warn of sorts but I don't think we have that... yet.

--
Regards/Gruss,
Boris.

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