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Subject: Re: [RFC PATCH v3 6/8] x86/pti: don't mark the user PGD with
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To: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>,
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From: Dave Hansen <dave.hansen@linux.intel.com>
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On 02/23/2018 09:58 AM, Konrad Rzeszutek Wilk wrote:
>> We also need to clear the RSB on vmexit, as documented. And if we
>> really want 100% support for retpoline on SKL+ instead of saying "use
>> IBRS if you're paranoid", then there are a few more cases where we need
>> to stuff it to avoid underflow (which is the same operation, but Arjan
>> insists we should differentiate the two, which is reasonable enough).
> Are these cases documented somewhere along with what approaches are taken?

Some of them are documented here: https://goo.gl/pXbvBE