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Subject: Re: [RFC PATCH v2 6/6] x86/entry/pti: don't switch PGD on when
 pti_disable is set
To: Josh Poimboeuf <jpoimboe@redhat.com>,
        Alexei Starovoitov <alexei.starovoitov@gmail.com>
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On 01/11/2018 10:32 AM, Josh Poimboeuf wrote:
>> hmm. Exposing cr3 to user space will make it trivial for user process
>> to know whether kpti is active. Not sure how exploitable such
>> information leak.
> It's already trivial to detect PTI from user space.

Do tell.