mirror of https://github.com/acidanthera/audk.git
20da7ca42a
BZ: https://bugzilla.tianocore.org/show_bug.cgi?id=2198 Before UEFI transfers control to the OS, it must park the AP. This is done using the AsmRelocateApLoop function to transition into 32-bit non-paging mode. For an SEV-ES guest, a few additional things must be done: - AsmRelocateApLoop must be updated to support SEV-ES. This means performing a VMGEXIT AP Reset Hold instead of an MWAIT or HLT loop. - Since the AP must transition to real mode, a small routine is copied to the WakeupBuffer area. Since the WakeupBuffer will be used by the AP during OS booting, it must be placed in reserved memory. Additionally, the AP stack must be located where it can be accessed in real mode. - Once the AP is in real mode it will transfer control to the destination specified by the OS in the SEV-ES AP Jump Table. The SEV-ES AP Jump Table address is saved by the hypervisor for the OS using the GHCB VMGEXIT AP Jump Table exit code. Cc: Eric Dong <eric.dong@intel.com> Cc: Ray Ni <ray.ni@intel.com> Cc: Laszlo Ersek <lersek@redhat.com> Reviewed-by: Eric Dong <eric.dong@intel.com> Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com> Regression-tested-by: Laszlo Ersek <lersek@redhat.com> |
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MpEqu.inc | ||
MpFuncs.nasm |