For supporting VCPU hotplug with SMM enabled/required, QEMU offers the (dynamically detectable) feature called "SMRAM at default SMBASE". When the feature is enabled, the firmware can lock down the 128 KB range starting at the default SMBASE; that is, the [0x3_0000, 0x4_FFFF] interval. The goal is to shield the very first SMI handler of the hotplugged VCPU from OS influence.
Multiple modules in OVMF will have to inter-operate for locking down this range. Introduce a dynamic PCD that will reflect the feature (to be negotiated by PlatformPei), for coordination between drivers. Cc: Ard Biesheuvel <ard.biesheu...@linaro.org> Cc: Boris Ostrovsky <boris.ostrov...@oracle.com> Cc: Brijesh Singh <brijesh.si...@amd.com> Cc: Igor Mammedov <imamm...@redhat.com> Cc: Jiewen Yao <jiewen....@intel.com> Cc: Joao M Martins <joao.m.mart...@oracle.com> Cc: Jordan Justen <jordan.l.jus...@intel.com> Cc: Jun Nakajima <jun.nakaj...@intel.com> Cc: Michael Kinney <michael.d.kin...@intel.com> Cc: Paolo Bonzini <pbonz...@redhat.com> Cc: Phillip Goerl <phillip.go...@oracle.com> Cc: Yingwen Chen <yingwen.c...@intel.com> Ref: https://bugzilla.tianocore.org/show_bug.cgi?id=1512 Signed-off-by: Laszlo Ersek <ler...@redhat.com> --- OvmfPkg/OvmfPkg.dec | 6 ++++++ OvmfPkg/OvmfPkgIa32.dsc | 1 + OvmfPkg/OvmfPkgIa32X64.dsc | 1 + OvmfPkg/OvmfPkgX64.dsc | 1 + 4 files changed, 9 insertions(+) diff --git a/OvmfPkg/OvmfPkg.dec b/OvmfPkg/OvmfPkg.dec index d5fee805ef4a..57034c784f88 100644 --- a/OvmfPkg/OvmfPkg.dec +++ b/OvmfPkg/OvmfPkg.dec @@ -257,6 +257,12 @@ [PcdsDynamic, PcdsDynamicEx] # This PCD is only accessed if PcdSmmSmramRequire is TRUE (see below). gUefiOvmfPkgTokenSpaceGuid.PcdQ35TsegMbytes|8|UINT16|0x20 + ## Set to TRUE by PlatformPei if the Q35 board supports the "SMRAM at default + # SMBASE" feature. + # + # This PCD is only accessed if PcdSmmSmramRequire is TRUE (see below). + gUefiOvmfPkgTokenSpaceGuid.PcdQ35SmramAtDefaultSmbase|FALSE|BOOLEAN|0x34 + [PcdsFeatureFlag] gUefiOvmfPkgTokenSpaceGuid.PcdQemuBootOrderPciTranslation|TRUE|BOOLEAN|0x1c gUefiOvmfPkgTokenSpaceGuid.PcdQemuBootOrderMmioTranslation|FALSE|BOOLEAN|0x1d diff --git a/OvmfPkg/OvmfPkgIa32.dsc b/OvmfPkg/OvmfPkgIa32.dsc index 66e944436a69..8a970a40cc62 100644 --- a/OvmfPkg/OvmfPkgIa32.dsc +++ b/OvmfPkg/OvmfPkgIa32.dsc @@ -561,6 +561,7 @@ [PcdsDynamicDefault] !if $(SMM_REQUIRE) == TRUE gUefiOvmfPkgTokenSpaceGuid.PcdQ35TsegMbytes|8 + gUefiOvmfPkgTokenSpaceGuid.PcdQ35SmramAtDefaultSmbase|FALSE gUefiCpuPkgTokenSpaceGuid.PcdCpuSmmSyncMode|0x01 gUefiCpuPkgTokenSpaceGuid.PcdCpuSmmApSyncTimeout|100000 !endif diff --git a/OvmfPkg/OvmfPkgIa32X64.dsc b/OvmfPkg/OvmfPkgIa32X64.dsc index 51c2bfb44f14..2a3ba9ec2ca1 100644 --- a/OvmfPkg/OvmfPkgIa32X64.dsc +++ b/OvmfPkg/OvmfPkgIa32X64.dsc @@ -573,6 +573,7 @@ [PcdsDynamicDefault] !if $(SMM_REQUIRE) == TRUE gUefiOvmfPkgTokenSpaceGuid.PcdQ35TsegMbytes|8 + gUefiOvmfPkgTokenSpaceGuid.PcdQ35SmramAtDefaultSmbase|FALSE gUefiCpuPkgTokenSpaceGuid.PcdCpuSmmSyncMode|0x01 gUefiCpuPkgTokenSpaceGuid.PcdCpuSmmApSyncTimeout|100000 !endif diff --git a/OvmfPkg/OvmfPkgX64.dsc b/OvmfPkg/OvmfPkgX64.dsc index ba7a75884490..17a135a8edfe 100644 --- a/OvmfPkg/OvmfPkgX64.dsc +++ b/OvmfPkg/OvmfPkgX64.dsc @@ -572,6 +572,7 @@ [PcdsDynamicDefault] !if $(SMM_REQUIRE) == TRUE gUefiOvmfPkgTokenSpaceGuid.PcdQ35TsegMbytes|8 + gUefiOvmfPkgTokenSpaceGuid.PcdQ35SmramAtDefaultSmbase|FALSE gUefiCpuPkgTokenSpaceGuid.PcdCpuSmmSyncMode|0x01 gUefiCpuPkgTokenSpaceGuid.PcdCpuSmmApSyncTimeout|100000 !endif -- 2.19.1.3.g30247aa5d201 -=-=-=-=-=-=-=-=-=-=-=- Groups.io Links: You receive all messages sent to this group. View/Reply Online (#47925): https://edk2.groups.io/g/devel/message/47925 Mute This Topic: https://groups.io/mt/34274936/21656 Group Owner: devel+ow...@edk2.groups.io Unsubscribe: https://edk2.groups.io/g/devel/unsub [arch...@mail-archive.com] -=-=-=-=-=-=-=-=-=-=-=-
