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    SubjectRe: [PATCH v7 04/20] x86/virt/tdx: Add skeleton to initialize TDX on demand
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    On Wed, 2022-11-23 at 08:58 -0800, Dave Hansen wrote:
    > On 11/23/22 02:18, Huang, Kai wrote:
    > > > Again, there are a lot of words in that comment, but I'm not sure why
    > > > it's here. Despite all the whinging about ACPI, doesn't it boil down to:
    > > >
    > > > The TDX module itself establishes its own concept of how many
    > > > logical CPUs there are in the system when it is loaded.
    > > >
    > > This isn't accurate. TDX MCHECK records the total number of logical CPUs when
    > > the BIOS enables TDX. This happens before the TDX module is loaded. In fact
    > > the TDX module only gets this information from a secret location.
    >
    > Kai, this is the point where I lose patience with the conversation
    > around this series. I'll you paste you the line of code where the TDX
    > module literally "establishes its own concept of how many logical CPUs
    > there are in the system":
    >
    > > //NUM_LPS
    > > tdx_global_data_ptr->num_of_lps = sysinfo_table_ptr->mcheck_fields.tot_num_lps;
    >
    > Yes, this is derived directly from MCHECK. But, this concept is
    > separate from MCHECK. We have seen zero actual facts from you or other
    > folks at Intel that this is anything other than an arbitrary choice made
    > for the convenience of the TDX module. It _might_ not be this way. I'm
    > open to hearing those facts and changing my position on this.
    >
    > But, please bring facts, not random references to "secret locations"
    > that aren't that secret.

    Agreed. Thanks for providing the comment and will use it.
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