Re: [EXTERNAL] Re: [PATCH v3] x86/hyperv: add noop functions to x86_init mpparse functions

From: Dave Hansen
Date: Tue Aug 01 2023 - 17:52:46 EST

On 7/21/23 05:58, Saurabh Singh Sengar wrote:
>> On Fri, Jun 23, 2023 at 09:28:08AM -0700, Saurabh Sengar wrote:
>>> Hyper-V can run VMs at different privilege "levels" known as Virtual
>>> Trust Levels (VTL). Sometimes, it chooses to run two different VMs at
>>> different levels but they share some of their address space. In such
>>> setups VTL2 (higher level VM) has visibility of all of the
>>> VTL0 (level 0) memory space.
>>> When the CONFIG_X86_MPPARSE is enabled for VTL2, the VTL2 kernel
>>> performs a search within the low memory to locate MP tables. However,
>>> in systems where VTL0 manages the low memory and may contain valid
>>> tables, this scanning can result in incorrect MP table information
>>> being provided to the VTL2 kernel, mistakenly considering VTL0's MP
>>> table as its own
>>> Add noop functions to avoid MP parse scan by VTL2.
>>> Signed-off-by: Saurabh Sengar <ssengar@xxxxxxxxxxxxxxxxxxx>
>> Hi Dave, are you happy with the commit message?
> HI Dave,
> If there is no concern, can I get your ack

Looks sane:

Acked-by: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>

Although, if you muck with this any more having actual facts on what the
"incorrect MP table information" causes would be nice too.