On 02/05/20 00:01, Lendacky, Thomas wrote: > BZ: https://bugzilla.tianocore.org/show_bug.cgi?id=2198 > > Reserve a fixed area of memory for SEV-ES use and set a fixed PCD, > PcdSevEsWorkAreaBase, to this value. > > This area will be used by SEV-ES support for two purposes: > 1. Communicating the SEV-ES status during BSP boot to SEC: > Using a byte of memory from the page, the BSP reset vector code can > communicate the SEV-ES status to SEC for use before exception > handling can be enabled in SEC. After SEC, this field is no longer > valid and the standard way of determine if SEV-ES is active should > be used. > > 2. Establishing an area of memory for AP boot support: > A hypervisor is not allowed to update an SEV-ES guest's register > state, so when booting an SEV-ES guest AP, the hypervisor is not > allowed to set the RIP to the guest requested value. Instead an > SEV-ES AP must be re-directed from within the guest to the actual > requested staring location as specified in the INIT-SIPI-SIPI > sequence. > > Use this memory for reset vector code that can be programmed to have > the AP jump to the desired RIP location after starting the AP. This > is required for only the very first AP reset. > > Cc: Jordan Justen <jordan.l.jus...@intel.com> > Cc: Laszlo Ersek <ler...@redhat.com> > Cc: Ard Biesheuvel <ard.biesheu...@linaro.org> > Signed-off-by: Tom Lendacky <thomas.lenda...@amd.com> > --- > OvmfPkg/OvmfPkgX64.fdf | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/OvmfPkg/OvmfPkgX64.fdf b/OvmfPkg/OvmfPkgX64.fdf > index f541481dc95c..3504aa35dc37 100644 > --- a/OvmfPkg/OvmfPkgX64.fdf > +++ b/OvmfPkg/OvmfPkgX64.fdf > @@ -82,6 +82,9 @@ [FD.MEMFD] > 0x009000|0x002000 > > gUefiCpuPkgTokenSpaceGuid.PcdSecGhcbBase|gUefiCpuPkgTokenSpaceGuid.PcdSecGhcbSize > > +0x00B000|0x001000 > +gUefiCpuPkgTokenSpaceGuid.PcdSevEsWorkAreaBase|gUefiCpuPkgTokenSpaceGuid.PcdSevEsWorkAreaSize > + > 0x010000|0x010000 > > gUefiOvmfPkgTokenSpaceGuid.PcdOvmfSecPeiTempRamBase|gUefiOvmfPkgTokenSpaceGuid.PcdOvmfSecPeiTempRamSize > >
Reviewed-by: Laszlo Ersek <ler...@redhat.com> -=-=-=-=-=-=-=-=-=-=-=- Groups.io Links: You receive all messages sent to this group. View/Reply Online (#53847): https://edk2.groups.io/g/devel/message/53847 Mute This Topic: https://groups.io/mt/70984999/21656 Group Owner: devel+ow...@edk2.groups.io Unsubscribe: https://edk2.groups.io/g/devel/unsub [arch...@mail-archive.com] -=-=-=-=-=-=-=-=-=-=-=-
