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Date:   Fri, 30 Apr 2021 21:56:57 +0200
From:   Borislav Petkov <bp@alien8.de>
To:     Reiji Watanabe <reijiw@google.com>
Cc:     Ramakrishna Saripalli <rsaripal@amd.com>,
        linux-kernel@vger.kernel.org, x86@kernel.org, tglx@linutronix.de,
        mingo@redhat.com, hpa@zytor.com, Jonathan Corbet <corbet@lwn.net>,
        bsd@redhat.com
Subject: Re: [PATCH v4 1/1] x86/cpufeatures: Implement Predictive Store
 Forwarding control.
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On Fri, Apr 30, 2021 at 12:42:46PM -0700, Reiji Watanabe wrote:
> Then, it would be a problem if its guests want to use PSFD looking at
> x86_virt_spec_ctrl().

Well, will they want to do that? If so, why? Use case?

We decided to do this lite version to give people the opportunity to
evaluate whether there's a need to make full-blown mitigation-like,
per-thread thing like the rest of the mitigations in bugs.c or leave it
to be a chicken-bit thing.

So do you have any particular use case in mind or are you simply poking
holes in this?

-- 
Regards/Gruss,
    Boris.

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