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Subject: Re: [patch RFC 5/5] x86/speculation: Add basic speculation control
 code
To: "Van De Ven, Arjan" <arjan.van.de.ven@intel.com>,
        Andrea Arcangeli <aarcange@redhat.com>
Cc: David Woodhouse <dwmw2@infradead.org>,
        Jiri Kosina <jikos@kernel.org>,
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From: Tim Chen <tim.c.chen@linux.intel.com>
Message-ID: <f8990c30-3e50-852c-81e3-1be2ae8e7d07@linux.intel.com>
Date: Wed, 10 Jan 2018 13:35:45 -0800
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On 01/10/2018 05:53 AM, Van De Ven, Arjan wrote:
>> ibrs_enabled 2:
>>
>> sets IBRS always in host
> 
> this is not secure
> 
>> This matches the semantics described here by Tim patchset on lkml:
>>
>> https://marc.info/?l=linux-kernel&m=151520606320646
> 
> I will talk to Tim, it's not right.
> 
> 

Yes, there's a misunderstanding on my part.  Leaving IBRS=1 all the
time may not provide full protection on all cpu models.

Tim