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Subject: Re: [PATCH 4/4] x86,module: Detect CRn and DRn manipulation
To:     Andrew Cooper <andrew.cooper3@citrix.com>,
        Nadav Amit <nadav.amit@gmail.com>,
        Peter Zijlstra <peterz@infradead.org>
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        Doug Covelli <dcovelli@vmware.com>, mhiramat@kernel.org
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From:   Paolo Bonzini <pbonzini@redhat.com>
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Date:   Wed, 8 Apr 2020 02:22:45 +0200
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On 08/04/20 01:15, Andrew Cooper wrote:
>> Anyhow, I do not think it is the only use-case which is not covered by your
>> patches (even considering CRs/DRs alone). For example, there is no kernel
>> function to turn on CR4.VMXE, which is required to run hypervisors on x86.
> How about taking this opportunity to see if there is a way to improve on
> the status quo for co-existing hypervisor modules?

Almost serious question: why?  I can understand VMware, but why can't at
least VirtualBox use KVM on Linux?  I am not sure if they are still
running device emulation in ring zero, but if so do you really want to
do that these days?

Paolo