BZ: https://bugzilla.tianocore.org/show_bug.cgi?id=3863
The intention of PlatformInitLib is to extract the common function used
in OvmfPkg/PlatformPei. This lib will be used not only in PEI phase but
also in SEC phase. SEC phase cannot use global variables between
different functions. So PlatformInfoHob is created to hold the
informations shared between functions. For example, HostBridgeDevId
corespond to mHostBridgeDevId in PlatformPei.
In this patch we will first move below global variables to
PlatformInfoHob.
- mBootMode
- mS3Supported
- mPhysMemAddressWidth
- mMaxCpuCount
- mHostBridgeDevId
- mQ35SmramAtDefaultSmbase
- mQemuUc32Base
- mS3AcpiReservedMemorySize
- mS3AcpiReservedMemoryBase
PlatformInfoHob also holds other information, for example,
PciIoBase / PciIoSize. This is because in SEC phase, PcdSetxxx
doesn't work. So we will restruct the functions which set PCDs
into two, one for PlatformInfoLib, one for PlatformPei.
So in this patch we first move global variables and PCDs to
PlatformInfoHob. All the changes are in OvmfPkg/PlatformPei.
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>
Cc: Sebastien Boeuf <sebastien.boeuf@intel.com>
Acked-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Jiewen Yao <jiewen.yao@intel.com>
Signed-off-by: Min Xu <min.m.xu@intel.com>
BZ: https://bugzilla.tianocore.org/show_bug.cgi?id=3863
There are 3 variants of PlatformPei in OvmfPkg:
- OvmfPkg/PlatformPei
- OvmfPkg/XenPlatformPei
- OvmfPkg/Bhyve/PlatformPei/PlatformPei.inf
These PlatformPeis can share many common codes, such as
Cmos / Hob / Memory / Platform related functions. This commit
(and its following several patches) are to create a PlatformInitLib
which wraps the common code called in above PlatformPeis.
In this initial version of PlatformInitLib, below Cmos related functions
are introduced:
- PlatformCmosRead8
- PlatformCmosWrite8
- PlatformDebugDumpCmos
They correspond to the functions in OvmfPkg/PlatformPei:
- CmosRead8
- CmosWrite8
- DebugDumpCmos
Considering this PlatformInitLib will be used in SEC phase, global
variables and dynamic PCDs are avoided. We use PlatformInfoHob
to exchange information between functions.
EFI_HOB_PLATFORM_INFO is the data struct which contains the platform
information, such as HostBridgeDevId, BootMode, S3Supported,
SmmSmramRequire, etc.
After PlatformInitLib is created, OvmfPkg/PlatformPei is refactored
with this library.
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>
Acked-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Jiewen Yao <jiewen.yao@intel.com>
Signed-off-by: Min Xu <min.m.xu@intel.com>
Instead of using the CMOS, the CloudHv platform relies on the list of
memmap entries provided through the PVH boot protocol to determine the
last RAM address below 4G.
Acked-by: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
Reviewed-by: Jiewen Yao <jiewen.yao@intel.com>
Prefer the e820 map provided via qemu firmware config interface
for memory detection. Use rtc cmos only as fallback, which should
be rarely needed these days as qemu supports etc/e820 since 2013.
Ref: https://bugzilla.tianocore.org/show_bug.cgi?id=3593
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Philippe Mathieu-Daude <philmd@redhat.com>
Add a bool parameter to ScanOrAdd64BitE820Ram to explicitly specify
whenever ScanOrAdd64BitE820Ram should add HOBs for high memory (above
4G) or scan only.
Also add a lowmem parameter so ScanOrAdd64BitE820Ram
can report the memory size below 4G.
This allows a more flexible usage of ScanOrAdd64BitE820Ram,
a followup patch will use it for all memory detection.
No functional change.
Ref: https://bugzilla.tianocore.org/show_bug.cgi?id=3593
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Philippe Mathieu-Daude <philmd@redhat.com>
FdtClient is unhappy without a device tree, so add an empty fdt
which we can use in case etc/fdt is not present in fw_cfg.
On ARM machines a device tree is mandatory for hardware detection,
that's why FdtClient fails hard.
On microvm the device tree is only used to detect virtio-mmio devices
(this patch series) and the pcie host (future series). So edk2 can
continue with limited functionality in case no device tree is present:
no storage, no network, but serial console and direct kernel boot
works.
qemu release 6.2 & newer will provide a device tree for microvm.
Ref: https://bugzilla.tianocore.org/show_bug.cgi?id=3689
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Philippe Mathieu-Daude <philmd@redhat.com>
BZ: https://bugzilla.tianocore.org/show_bug.cgi?id=3275
When SEV-SNP is active, a memory region mapped encrypted in the page
table must be validated before access. There are two approaches that
can be taken to validate the system RAM detected during the PEI phase:
1) Validate on-demand
OR
2) Validate before access
On-demand
=========
If memory is not validated before access, it will cause a #VC
exception with the page-not-validated error code. The VC exception
handler can perform the validation steps.
The pages that have been validated will need to be tracked to avoid
the double validation scenarios. The range of memory that has not
been validated will need to be communicated to the OS through the
recently introduced unaccepted memory type
https://github.com/microsoft/mu_basecore/pull/66, so that OS can
validate those ranges before using them.
Validate before access
======================
Since the PEI phase detects all the available system RAM, use the
MemEncryptSevSnpValidateSystemRam() function to pre-validate the
system RAM in the PEI phase.
For now, choose option 2 due to the dependency and the complexity
of the on-demand validation.
Cc: Michael Roth <michael.roth@amd.com>
Cc: James Bottomley <jejb@linux.ibm.com>
Cc: Min Xu <min.m.xu@intel.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Jordan Justen <jordan.l.justen@intel.com>
Cc: Ard Biesheuvel <ardb+tianocore@kernel.org>
Cc: Erdem Aktas <erdemaktas@google.com>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Acked-by: Jiewen Yao <Jiewen.yao@intel.com>
Acked-by: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
BZ: https://bugzilla.tianocore.org/show_bug.cgi?id=3108
Protect the GHCB backup pages used by an SEV-ES guest when S3 is
supported.
Regarding the lifecycle of the GHCB backup pages:
PcdOvmfSecGhcbBackupBase
(a) when and how it is initialized after first boot of the VM
If SEV-ES is enabled, the GHCB backup pages are initialized when a
nested #VC is received during the SEC phase
[OvmfPkg/Library/VmgExitLib/SecVmgExitVcHandler.c].
(b) how it is protected from memory allocations during DXE
If S3 and SEV-ES are enabled, then InitializeRamRegions()
[OvmfPkg/PlatformPei/MemDetect.c] protects the ranges with an AcpiNVS
memory allocation HOB, in PEI.
If S3 is disabled, then these ranges are not protected. PEI switches to
the GHCB backup pages in permanent PEI memory and DXE will use these
PEI GHCB backup pages, so we don't have to preserve
PcdOvmfSecGhcbBackupBase.
(c) how it is protected from the OS
If S3 is enabled, then (b) reserves it from the OS too.
If S3 is disabled, then the range needs no protection.
(d) how it is accessed on the S3 resume path
It is rewritten same as in (a), which is fine because (b) reserved it.
(e) how it is accessed on the warm reset path
It is rewritten same as in (a).
Cc: Jordan Justen <jordan.l.justen@intel.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Cc: Ard Biesheuvel <ard.biesheuvel@arm.com>
Cc: Anthony Perard <anthony.perard@citrix.com>
Cc: Julien Grall <julien@xen.org>
Cc: Brijesh Singh <brijesh.singh@amd.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Message-Id: <119102a3d14caa70d81aee334a2e0f3f925e1a60.1610045305.git.thomas.lendacky@amd.com>
BZ: https://bugzilla.tianocore.org/show_bug.cgi?id=3108
In order to be able to issue messages or make interface calls that cause
another #VC (e.g. GetLocalApicBaseAddress () issues RDMSR), add support
for nested #VCs.
In order to support nested #VCs, GHCB backup pages are required. If a #VC
is received while currently processing a #VC, a backup of the current GHCB
content is made. This allows the #VC handler to continue processing the
new #VC. Upon completion of the new #VC, the GHCB is restored from the
backup page. The #VC recursion level is tracked in the per-vCPU variable
area.
Support is added to handle up to one nested #VC (or two #VCs total). If
a second nested #VC is encountered, an ASSERT will be issued and the vCPU
will enter CpuDeadLoop ().
For SEC, the GHCB backup pages are reserved in the OvmfPkgX64.fdf memory
layout, with two new fixed PCDs to provide the address and size of the
backup area.
For PEI/DXE, the GHCB backup pages are allocated as boot services pages
using the memory allocation library.
Cc: Jordan Justen <jordan.l.justen@intel.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Cc: Ard Biesheuvel <ard.biesheuvel@arm.com>
Cc: Brijesh Singh <brijesh.singh@amd.com>
Acked-by: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Message-Id: <ac2e8203fc41a351b43f60d68bdad6b57c4fb106.1610045305.git.thomas.lendacky@amd.com>
BZ: https://bugzilla.tianocore.org/show_bug.cgi?id=2198
After having transitioned from UEFI to the OS, the OS will need to boot
the APs. For an SEV-ES guest, the APs will have been parked by UEFI using
GHCB pages allocated by UEFI. The hypervisor will write to the GHCB
SW_EXITINFO2 field of the GHCB when the AP is booted. As a result, the
GHCB pages must be marked reserved so that the OS does not attempt to use
them and experience memory corruption because of the hypervisor write.
Change the GHCB allocation from the default boot services memory to
reserved memory.
Cc: Jordan Justen <jordan.l.justen@intel.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Cc: Ard Biesheuvel <ard.biesheuvel@arm.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Regression-tested-by: Laszlo Ersek <lersek@redhat.com>
BZ: https://bugzilla.tianocore.org/show_bug.cgi?id=2198
Protect the SEV-ES work area memory used by an SEV-ES guest.
Regarding the lifecycle of the SEV-ES memory area:
PcdSevEsWorkArea
(a) when and how it is initialized after first boot of the VM
If SEV-ES is enabled, the SEV-ES area is initialized during
the SEC phase [OvmfPkg/ResetVector/Ia32/PageTables64.asm].
(b) how it is protected from memory allocations during DXE
If SEV-ES is enabled, then InitializeRamRegions()
[OvmfPkg/PlatformPei/MemDetect.c] protects the ranges with either
an AcpiNVS (S3 enabled) or BootServicesData (S3 disabled) memory
allocation HOB, in PEI.
(c) how it is protected from the OS
If S3 is enabled, then (b) reserves it from the OS too.
If S3 is disabled, then the range needs no protection.
(d) how it is accessed on the S3 resume path
It is rewritten same as in (a), which is fine because (b) reserved it.
(e) how it is accessed on the warm reset path
It is rewritten same as in (a).
Cc: Jordan Justen <jordan.l.justen@intel.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Cc: Ard Biesheuvel <ard.biesheuvel@arm.com>
Cc: Anthony Perard <anthony.perard@citrix.com>
Cc: Julien Grall <julien@xen.org>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Regression-tested-by: Laszlo Ersek <lersek@redhat.com>
BZ: https://bugzilla.tianocore.org/show_bug.cgi?id=2198
The SEV support will clear the C-bit from non-RAM areas. The early GDT
lives in a non-RAM area, so when an exception occurs (like a #VC) the GDT
will be read as un-encrypted even though it is encrypted. This will result
in a failure to be able to handle the exception.
Move the GDT into RAM so it can be accessed without error when running as
an SEV-ES guest.
Cc: Jordan Justen <jordan.l.justen@intel.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Cc: Ard Biesheuvel <ard.biesheuvel@arm.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Regression-tested-by: Laszlo Ersek <lersek@redhat.com>
BZ: https://bugzilla.tianocore.org/show_bug.cgi?id=2198
Allocate memory for the GHCB pages and the per-CPU variable pages during
SEV initialization for use during Pei and Dxe phases. The GHCB page(s)
must be shared pages, so clear the encryption mask from the current page
table entries. Upon successful allocation, set the GHCB PCDs (PcdGhcbBase
and PcdGhcbSize).
The per-CPU variable page needs to be unique per AP. Using the page after
the GHCB ensures that it is unique per AP. Only the GHCB page is marked as
shared, keeping the per-CPU variable page encyrpted. The same logic is
used in DXE using CreateIdentityMappingPageTables() before switching to
the DXE pagetables.
The GHCB pages (one per vCPU) will be used by the PEI and DXE #VC
exception handlers. The #VC exception handler will fill in the necessary
fields of the GHCB and exit to the hypervisor using the VMGEXIT
instruction. The hypervisor then accesses the GHCB associated with the
vCPU in order to perform the requested function.
Cc: Jordan Justen <jordan.l.justen@intel.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Cc: Ard Biesheuvel <ard.biesheuvel@arm.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Regression-tested-by: Laszlo Ersek <lersek@redhat.com>
BZ: https://bugzilla.tianocore.org/show_bug.cgi?id=2198
Protect the memory used by an SEV-ES guest when S3 is supported. This
includes the page table used to break down the 2MB page that contains
the GHCB so that it can be marked un-encrypted, as well as the GHCB
area.
Regarding the lifecycle of the GHCB-related memory areas:
PcdOvmfSecGhcbPageTableBase
PcdOvmfSecGhcbBase
(a) when and how it is initialized after first boot of the VM
If SEV-ES is enabled, the GHCB-related areas are initialized during
the SEC phase [OvmfPkg/ResetVector/Ia32/PageTables64.asm].
(b) how it is protected from memory allocations during DXE
If S3 and SEV-ES are enabled, then InitializeRamRegions()
[OvmfPkg/PlatformPei/MemDetect.c] protects the ranges with an AcpiNVS
memory allocation HOB, in PEI.
If S3 is disabled, then these ranges are not protected. DXE's own page
tables are first built while still in PEI (see HandOffToDxeCore()
[MdeModulePkg/Core/DxeIplPeim/X64/DxeLoadFunc.c]). Those tables are
located in permanent PEI memory. After CR3 is switched over to them
(which occurs before jumping to the DXE core entry point), we don't have
to preserve PcdOvmfSecGhcbPageTableBase. PEI switches to GHCB pages in
permanent PEI memory and DXE will use these PEI GHCB pages, so we don't
have to preserve PcdOvmfSecGhcbBase.
(c) how it is protected from the OS
If S3 is enabled, then (b) reserves it from the OS too.
If S3 is disabled, then the range needs no protection.
(d) how it is accessed on the S3 resume path
It is rewritten same as in (a), which is fine because (b) reserved it.
(e) how it is accessed on the warm reset path
It is rewritten same as in (a).
Cc: Jordan Justen <jordan.l.justen@intel.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Cc: Ard Biesheuvel <ard.biesheuvel@arm.com>
Cc: Anthony Perard <anthony.perard@citrix.com>
Cc: Julien Grall <julien@xen.org>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Regression-tested-by: Laszlo Ersek <lersek@redhat.com>
The previous patch has no effect -- i.e., it cannot stop the tracking of
BS Code/Data in MemTypeInfo -- if the virtual machine already has a
MemoryTypeInformation UEFI variable.
In that case, our current logic allows the DXE IPL PEIM to translate the
UEFI variable to the HOB, and that translation is verbatim. If the
variable already contains records for BS Code/Data, the issues listed in
the previous patch persist for the virtual machine.
For this reason, *always* install PlatformPei's own MemTypeInfo HOB. This
prevents the DXE IPL PEIM's variable-to-HOB translation.
In PlatformPei, consume the records in the MemoryTypeInformation UEFI
variable as hints:
- Ignore all memory types for which we wouldn't by default install records
in the HOB. This hides BS Code/Data from any existent
MemoryTypeInformation variable.
- For the memory types that our defaults cover, enable the records in the
UEFI variable to increase (and *only* to increase) the page counts.
This lets the MemoryTypeInformation UEFI variable function as designed,
but it eliminates a reboot when such a new OVMF binary is deployed (a)
that has higher memory consumption than tracked by the virtual machine's
UEFI variable previously, *but* (b) whose defaults also reflect those
higher page counts.
Cc: Ard Biesheuvel <ard.biesheuvel@arm.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Jordan Justen <jordan.l.justen@intel.com>
Cc: Philippe Mathieu-Daudé <philmd@redhat.com>
Ref: https://bugzilla.tianocore.org/show_bug.cgi?id=2706
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Message-Id: <20200508121651.16045-3-lersek@redhat.com>
Reviewed-by: Ard Biesheuvel <ard.biesheuvel@arm.com>
