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Re: [PATCH v2] x86/PVH: restore VMX APIC assist for Dom0


  • To: Jan Beulich <jbeulich@xxxxxxxx>, Roger Pau Monne <roger.pau@xxxxxxxxxx>
  • From: Andrew Cooper <Andrew.Cooper3@xxxxxxxxxx>
  • Date: Tue, 27 Sep 2022 15:29:48 +0000
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  • Thread-topic: [PATCH v2] x86/PVH: restore VMX APIC assist for Dom0

On 27/09/2022 15:38, Jan Beulich wrote:
> On 27.09.2022 16:32, Roger Pau Monné wrote:
>> On Mon, Sep 26, 2022 at 11:58:34AM +0200, Jan Beulich wrote:
>>> I don't expect it was intended to default PVH Dom0 to "no assist" mode.
>>> Introduce command line (sub-)options allowing to suppress enabling of
>>> the assists, paralleling the guest config settings for DomU, but restore
>>> the defaulting to "enabled".
>>>
>>> Fixes: 2ce11ce249a3 ("x86/HVM: allow per-domain usage of hardware 
>>> virtualized APIC")
>>> Signed-off-by: Jan Beulich <jbeulich@xxxxxxxx>
>> Reviewed-by: Roger Pau Monné <roger.pau@xxxxxxxxxx>

NACK.

You're both on the security team - stop churning code you know perfectly
well is in flux.

This patch goes nowhere until the issues are resolved, and the ABI is
unbroken.  Then and only then *might* there need to be an adjustment for
dom0.

~Andrew

 


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