Re: [PATCH V7 23/37] OvmfPkg: Update Sec to support Tdx

["Gerd Hoffmann" <kraxel@redhat.com>]

On Mon, Feb 28, 2022 at 03:20:55PM +0800, Min Xu wrote:
> RFC: https://bugzilla.tianocore.org/show_bug.cgi?id=3429
> 
> There are below major changes in this commit.
> 
> 1. SecEntry.nasm
> In TDX BSP and APs goes to the same entry point in SecEntry.nasm.
> 
> BSP initialize the temporary stack and then jumps to SecMain, just as
> legacy Ovmf does.
> 
> APs spin in a modified mailbox loop using initial mailbox structure.
> Its structure defition is in OvmfPkg/Include/IndustryStandard/IntelTdx.h.
> APs wait for command to see if the command is for me. If so execute the
> command.
> 
> 2. Sec/SecMain.c
> When host VMM create the Td guest, the system memory informations are
> stored in TdHob, which is a memory region described in Tdx metadata.
> The system memory region in TdHob should be accepted before it can be
> accessed. So the major task of this patch is to process the TdHobList
> to accept the memory. After that TDVF follow the standard OVMF flow
> and jump to PEI phase.
> 
> PcdUse1GPageTable is set to FALSE by default in OvmfPkgX64.dsc. It gives
> no chance for Intel TDX to support 1G page table. To support 1G page
> table this PCD is set to TRUE in OvmfPkgX64.dsc.
> 
> TDX_GUEST_SUPPORTED is defined in OvmfPkgX64.dsc. This macro wraps the
> Tdx specific code.
> 
> TDX only works on X64, so the code is only valid in X64 arch.
> 
> Cc: Ard Biesheuvel <ardb+tianocore@kernel.org>
> Cc: Jordan Justen <jordan.l.justen@intel.com>
> Cc: Brijesh Singh <brijesh.singh@amd.com>
> Cc: Erdem Aktas <erdemaktas@google.com>
> Cc: James Bottomley <jejb@linux.ibm.com>
> Cc: Jiewen Yao <jiewen.yao@intel.com>
> Cc: Tom Lendacky <thomas.lendacky@amd.com>
> Cc: Gerd Hoffmann <kraxel@redhat.com>
> Signed-off-by: Min Xu <min.m.xu@intel.com>

Acked-by: Gerd Hoffmann <kraxel@redhat.com>