elmarco and lersek OvmfPkg/PlatformPei: clear CPU caches
This is for conformance with the TCG "Platform Reset Attack Mitigation
Specification". Because clearing the CPU caches at boot doesn't impact
performance significantly, do it unconditionally, for simplicity's

Flush the cache on all logical processors, thanks to
EFI_PEI_MP_SERVICES_PPI and CacheMaintenanceLib.

Cc: Jordan Justen <jordan.l.justen@intel.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Anthony Perard <anthony.perard@citrix.com>
Cc: Julien Grall <julien.grall@linaro.org>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Tested-by: Anthony PERARD <anthony.perard@citrix.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Regression-tested-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Michael D Kinney <michael.d.kinney@intel.com>
[lersek@redhat.com: remove bogus Message-Id line from commit msg]
Latest commit d20ae95 Oct 2, 2018
Failed to load latest commit information.
AcpiPlatformDxe OvmfPkg/AcpiPlatformDxe: clean up libs and protos in "AcpiPlatformDxe… Jul 19, 2018
AcpiTables OvmfPkg: Removing ipf which is no longer supported from edk2. Jun 29, 2018
AmdSevDxe OvmfPkg/AmdSevDxe: decrypt the pages of the initial SMRAM save state map Mar 6, 2018
Csm OvmfPkg: Removing ipf which is no longer supported from edk2. Jun 29, 2018
EmuVariableFvbRuntimeDxe OvmfPkg: Removing ipf which is no longer supported from edk2. Jun 29, 2018
Include OvmfPkg: add QEMU_RAMFB_GUID Jun 14, 2018
IncompatiblePciDeviceSupportDxe OvmfPkg/IncompatiblePci: Do not use deprecated macros Feb 10, 2017
IoMmuDxe OvmfPkg/IoMmuDxe: list "AmdSevIoMmu.h" in the INF file Mar 13, 2018
Library OvmfPkg/PlatformDebugLibIoPort: fix port detection for use in the DXE… Aug 6, 2018
PciHotPlugInitDxe OvmfPkg/PciHotPlugInitDxe: convert to PciCapLib May 24, 2018
PlatformDxe OvmfPkg/PlatformDxe: list "PlatformConfig.h" in the INF file Mar 13, 2018
PlatformPei OvmfPkg/PlatformPei: clear CPU caches Oct 5, 2018
QemuFlashFvbServicesRuntimeDxe OvmfPkg/QemuFlashFvbServicesRuntimeDxe: Restore C-bit when SEV is active Jul 6, 2018
QemuRamfbDxe OvmfPkg: add QemuRamfbDxe Jun 14, 2018
QemuVideoDxe OvmfPkg: Removing ipf which is no longer supported from edk2. Jun 29, 2018
ResetVector OvmfPkg/ResetVector: Set C-bit when building initial page table Jul 11, 2017
SataControllerDxe OvmfPkg: Removing ipf which is no longer supported from edk2. Jun 29, 2018
Sec OvmfPkg: Removing ipf which is no longer supported from edk2. Jun 29, 2018
SmbiosPlatformDxe OvmfPkg: Removing ipf which is no longer supported from edk2. Jun 29, 2018
SmmAccess OvmfPkg/SmmAccess: support extended TSEG size Jul 5, 2017
SmmControl2Dxe OvmfPkg/SmmControl2Dxe: save fw_cfg boot script with QemuFwCfgS3Lib Mar 14, 2017
Tcg/Tcg2Config OvmfPkg/Tcg2ConfigPei: trivial coding style updates Mar 10, 2018
Virtio10Dxe OvmfPkg/Virtio10Dxe: convert to PciCapLib May 24, 2018
VirtioBlkDxe OvmfPkg:Fix VS2012 build failure Mar 28, 2018
VirtioGpuDxe OvmfPkg/VirtioGpuDxe: don't unmap VRING & BackingStore at ExitBootSer… Sep 8, 2017
VirtioNetDxe OvmfPkg/VirtioNetDxe: list "VirtioNet.h" in the INF file Mar 13, 2018
VirtioPciDeviceDxe OvmfPkg/VirtioPciDeviceDxe: list "VirtioPciDevice.h" in the INF file Mar 13, 2018
VirtioRngDxe OvmfPkg/VirtioRngDxe: list "VirtioRng.h" in the INF file Mar 13, 2018
VirtioScsiDxe OvmfPkg:Fix VS2012 build failure Mar 28, 2018
XenBusDxe OvmfPkg/XenBusDxe: Use EFIAPI for XenStoreVSPrint Feb 23, 2017
XenIoPciDxe OvmfPkg: Fix typos in comments Jul 8, 2016
XenPvBlkDxe OvmfPkg/XenPvBlkDxe: remove gEfiDevicePathProtocolGuid from [Protocols] Jul 20, 2018
DecomprScratchEnd.fdf.inc OvmfPkg: Sec: assert the build-time calculated end of the scratch buffer Nov 30, 2015
License.txt OvmfPkg: Undo removal of License.txt Aug 3, 2017
OvmfPkg.dec OvmfPkg: add QEMU_RAMFB_GUID Jun 14, 2018
OvmfPkg.fdf.inc OvmfPkg: introduce 4MB flash image (mainly) for Windows HCK May 4, 2017
OvmfPkgIa32.dsc OvmfPkg: link Sha384 and Sha512 support into Tcg2Pei and Tcg2Dxe Aug 16, 2018
OvmfPkgIa32.fdf OvmfPkg: add QemuRamfbDxe Jun 14, 2018
OvmfPkgIa32X64.dsc OvmfPkg: link Sha384 and Sha512 support into Tcg2Pei and Tcg2Dxe Aug 16, 2018
OvmfPkgIa32X64.fdf OvmfPkg: add QemuRamfbDxe Jun 14, 2018
OvmfPkgX64.dsc OvmfPkg: link Sha384 and Sha512 support into Tcg2Pei and Tcg2Dxe Aug 16, 2018
OvmfPkgX64.fdf OvmfPkg: add QemuRamfbDxe Jun 14, 2018
README OvmfPkg/README: add HTTPS Boot Apr 24, 2018
VarStore.fdf.inc OvmfPkg: introduce 4MB flash image (mainly) for Windows HCK May 4, 2017
build.sh Revert "OvmfPkg/build.sh: select the GCC49 toolchain settings for gcc… Aug 25, 2017
create-release.py OvmfPkg: Update web page and wiki urls Feb 5, 2015



The Open Virtual Machine Firmware (OVMF) project aims
to support firmware for Virtual Machines using the edk2
code base.  More information can be found at:


=== STATUS ===

Current capabilities:
* IA32 and X64 architectures
* QEMU (0.10.0 or later)
  - Video, keyboard, IDE, CD-ROM, serial
  - Runs UEFI shell
  - Optional NIC support.  Requires QEMU (0.12.2 or later)
* UEFI Linux boots
* UEFI Windows 8 boots
* UEFI Windows 7 & Windows 2008 Server boot (see important notes below!)


* Test/Stabilize UEFI Self-Certification Tests (SCT) results


* Build environment capable of build the edk2 MdeModulePkg.
* A properly configured ASL compiler:
  - Intel ASL compiler: Available from http://www.acpica.org
  - Microsoft ASL compiler: Available from http://www.acpi.info
* NASM: http://www.nasm.us/

Update Conf/target.txt ACTIVE_PLATFORM for OVMF:
                             PEI arch   DXE arch   UEFI interfaces
* OvmfPkg/OvmfPkgIa32.dsc      IA32       IA32           IA32
* OvmfPkg/OvmfPkgIa32X64.dsc   IA32       X64            X64
* OvmfPkg/OvmfPkgX64.dsc       X64        X64            X64

Update Conf/target.txt TARGET_ARCH based on the .dsc file:
* OvmfPkg/OvmfPkgIa32.dsc     IA32
* OvmfPkg/OvmfPkgIa32X64.dsc  IA32 X64
* OvmfPkg/OvmfPkgX64.dsc      X64

Following the edk2 build process, you will find the OVMF binaries
under the $WORKSPACE/Build/*/*/FV directory.  The actual path will
depend on how your build is configured.  You can expect to find
these binary outputs:
  - Please note!  This filename has changed.  Older releases used OVMF.Fv.
* OvmfVideo.rom
  - This file is not built separately any longer, starting with svn r13520.

More information on building OVMF can be found at:



* QEMU 0.12.2 or later is required.
* Be sure to use qemu-system-x86_64, if you are using and X64 firmware.
  (qemu-system-x86_64 works for the IA32 firmware as well, of course.)
* Use OVMF for QEMU firmware (3 options available)
  - Option 1: QEMU 1.6 or newer; Use QEMU -pflash parameter
    * QEMU/OVMF will use emulated flash, and fully support UEFI variables
    * Run qemu with: -pflash path/to/OVMF.fd
    * Note that this option is required for running SecureBoot-enabled builds
  - Option 2: Use QEMU -bios parameter
    * Note that UEFI variables will be partially emulated, and non-volatile
      variables may lose their contents after a reboot
    * Run qemu with: -bios path/to/OVMF.fd
  - Option 3: Use QEMU -L parameter
    * Note that UEFI variables will be partially emulated, and non-volatile
      variables may lose their contents after a reboot
    * Either copy, rename or symlink OVMF.fd => bios.bin
    * Use the QEMU -L parameter to specify the directory where the bios.bin
      file is located.
* The EFI shell is built into OVMF builds at this time, so it should
  run automatically if a UEFI boot application is not found on the
  removable media.
* On Linux, newer version of QEMU may enable KVM feature, and this might
  cause OVMF to fail to boot.  The QEMU '-no-kvm' may allow OVMF to boot.
* Capturing OVMF debug messages on qemu:
  - The default OVMF build writes debug messages to IO port 0x402.  The
    following qemu command line options save them in the file called
    debug.log: '-debugcon file:debug.log -global isa-debugcon.iobase=0x402'.
  - It is possible to revert to the original behavior, when debug messages were
    written to the emulated serial port (potentially intermixing OVMF debug
    output with UEFI serial console output).  For this the
    '-D DEBUG_ON_SERIAL_PORT' option has to be passed to the build command (see
    the next section), and in order to capture the serial output qemu needs to
    be started with eg. '-serial file:serial.log'.
  - Debug messages fall into several categories.  Logged vs. suppressed
    categories are controlled at OVMF build time by the
    'gEfiMdePkgTokenSpaceGuid.PcdDebugPrintErrorLevel' bitmask (an UINT32
    value) in the selected .dsc file.  Individual bits of this bitmask are
    defined in <MdePkg/Include/Library/DebugLib.h>.  One non-default bit (with
    some performance impact) that is frequently set for debugging is 0x00400000
  - The RELEASE build target ('-b RELEASE' build option, see below) disables
    all debug messages.  The default build target is DEBUG.

=== Build Scripts ===

On systems with the bash shell you can use OvmfPkg/build.sh to simplify
building and running OVMF.

So, for example, to build + run OVMF X64:
$ OvmfPkg/build.sh -a X64
$ OvmfPkg/build.sh -a X64 qemu

And to run a 64-bit UEFI bootable ISO image:
$ OvmfPkg/build.sh -a X64 qemu -cdrom /path/to/disk-image.iso

To build a 32-bit OVMF without debug messages using GCC 4.5:
$ OvmfPkg/build.sh -a IA32 -b RELEASE -t GCC45

=== SMM support ===

* SMM support requires QEMU 2.5.
* The minimum required QEMU machine type is "pc-q35-2.5".
* SMM with KVM requires Linux 4.4 (host).

OVMF is capable of utilizing SMM if the underlying QEMU or KVM hypervisor
emulates SMM. SMM is put to use in the S3 suspend and resume infrastructure,
and in the UEFI variable driver stack. The purpose is (virtual) hardware
separation between the runtime guest OS and the firmware (OVMF), with the
intent to make Secure Boot actually secure, by preventing the runtime guest OS
from tampering with the variable store and S3 areas.

For SMM support, OVMF must be built with the "-D SMM_REQUIRE" option. The
resultant firmware binary will check if QEMU actually provides SMM emulation;
if it doesn't, then OVMF will log an error and trigger an assertion failure
during boot (even in RELEASE builds). Both the naming of the flag (SMM_REQUIRE,
instead of SMM_ENABLE), and this behavior are consistent with the goal
described above: this is supposed to be a security feature, and fallbacks are
not allowed. Similarly, a pflash-backed variable store is a requirement.

QEMU should be started with the options listed below (in addition to any other
guest-specific flags). The command line should be gradually composed from the
hints below. '\' is used to extend the command line to multiple lines, and '^'
can be used on Windows.

* QEMU binary and options specific to 32-bit guests:

  $ qemu-system-i386 -cpu coreduo,-nx \


  $ qemu-system-x86_64 -cpu <MODEL>,-lm,-nx \

* QEMU binary for running 64-bit guests (no particular options):

  $ qemu-system-x86_64 \

* Flags common to all SMM scenarios (only the Q35 machine type is supported):

  -machine q35,smm=on,accel=(tcg|kvm) \
  -m ... \
  -smp ... \
  -global driver=cfi.pflash01,property=secure,value=on \
  -drive if=pflash,format=raw,unit=0,file=OVMF_CODE.fd,readonly=on \
  -drive if=pflash,format=raw,unit=1,file=copy_of_OVMF_VARS.fd \

* In order to disable S3, add:

  -global ICH9-LPC.disable_s3=1 \

=== Network Support ===

OVMF provides a UEFI network stack by default. Its lowest level driver is the
NIC driver, higher levels are generic. In order to make DHCP, PXE Boot, and eg.
socket test utilities from the StdLib edk2 package work, (1) qemu has to be
configured to emulate a NIC, (2) a matching UEFI NIC driver must be available
when OVMF boots.

(If a NIC is configured for the virtual machine, and -- dependent on boot order
-- PXE booting is attempted, but no DHCP server responds to OVMF's DHCP
DISCOVER message at startup, the boot process may take approx. 3 seconds

* For each NIC emulated by qemu, a GPLv2 licensed UEFI driver is available from
  the iPXE project. The qemu source distribution, starting with version 1.5,
  contains prebuilt binaries of these drivers (and of course allows one to
  rebuild them from source as well). This is the recommended set of drivers.

* Use the qemu -netdev and -device options, or the legacy -net option, to
  enable NIC support: <http://wiki.qemu.org/Documentation/Networking>.

* For a qemu >= 1.5 binary running *without* any "-M machine" option where
  "machine" would identify a < qemu-1.5 configuration (for example: "-M
  pc-i440fx-1.4" or "-M pc-0.13"), the iPXE drivers are automatically available
  to and configured for OVMF in the default qemu installation.

* For a qemu binary in [0.13, 1.5), or a qemu >= 1.5 binary with an "-M
  machine" option where "machine" selects a < qemu-1.5 configuration:

  - download a >= 1.5.0-rc1 source tarball from <http://wiki.qemu.org/Download>,

  - extract the following iPXE driver files from the tarball and install them
    in a location that is accessible to qemu processes (this may depend on your
    SELinux configuration, for example):


  - extend the NIC's -device option on the qemu command line with a matching
    "romfile=" optarg:

    -device e1000,...,romfile=/full/path/to/efi-e1000.rom
    -device ne2k_pci,...,romfile=/full/path/to/efi-ne2k_pci.rom
    -device pcnet,...,romfile=/full/path/to/efi-pcnet.rom
    -device rtl8139,...,romfile=/full/path/to/efi-rtl8139.rom
    -device virtio-net-pci,...,romfile=/full/path/to/efi-virtio.rom

* Independently of the iPXE NIC drivers, the default OVMF build provides a
  basic virtio-net driver, located in OvmfPkg/VirtioNetDxe.

* Also independently of the iPXE NIC drivers, Intel's proprietary E1000 NIC
  driver (from the BootUtil distribution) can be embedded in the OVMF image at
  build time:

  - Download BootUtil:
    - Navigate to
    - Click the download link for "PREBOOT.EXE".
    - Accept the Intel Software License Agreement that appears.
    - Unzip "PREBOOT.EXE" into a separate directory (this works with the
      "unzip" utility on platforms different from Windows as well).
    - Copy the "APPS/EFI/EFIx64/E3522X2.EFI" driver binary to
      "Intel3.5/EFIX64/E3522X2.EFI" in your WORKSPACE.
    - Intel have stopped distributing an IA32 driver binary (which used to
      match the filename pattern "E35??E2.EFI"), thus this method will only
      work for the IA32X64 and X64 builds of OVMF.

  - Include the driver in OVMF during the build:
    - Add "-D E1000_ENABLE" to your build command (only when building
      "OvmfPkg/OvmfPkgIa32X64.dsc" or "OvmfPkg/OvmfPkgX64.dsc").
    - For example: "build -D E1000_ENABLE".

* When a matching iPXE driver is configured for a NIC as described above, it
  takes priority over other drivers that could possibly drive the card too:

                         | e1000  ne2k_pci  pcnet  rtl8139  virtio-net-pci
    iPXE                 |   x       x        x       x           x
    VirtioNetDxe         |                                        x
    Intel BootUtil (X64) |   x

=== HTTPS Boot ===

HTTPS Boot is an alternative solution to PXE. It replaces the tftp server
with a HTTPS server so the firmware can download the images through a trusted
and encrypted connection.

* To enable HTTPS Boot, you have to build OVMF with -D HTTP_BOOT_ENABLE and
  -D TLS_ENABLE. The former brings in the HTTP stack from NetworkPkg while
  the latter enables TLS support in both NetworkPkg and CryptoPkg.

* By default, there is no trusted certificate. The user has to import the
  certificates either manually with "Tls Auth Configuration" utility in the
  firmware UI or through the fw_cfg entry, etc/edk2/https/cacerts.

  -fw_cfg name=etc/edk2/https/cacerts,file=<certdb>

  The blob for etc/edk2/https/cacerts has to be in the format of Signature
  Database(*1). You can use p11-kit(*2) or efisiglit(*3) to create the
  certificate list.

  If you want to create the certificate list based on the CA certificates
  in your local host, p11-kit will be a good choice. Here is the command to
  create the list:

  p11-kit extract --format=edk2-cacerts --filter=ca-anchors \
    --overwrite --purpose=server-auth <certdb>

  If you only want to import one certificate, efisiglist is the tool for you:

  efisiglist -a <cert file> -o <certdb>

  Please note that the certificate has to be in the DER format.

  You can also append a certificate to the existing list with the following

  efisiglist -i <old certdb> -a <cert file> -o <new certdb>

  NOTE: You may need the patch to make efisiglist generate the correct header.

* Besides the trusted certificates, it's also possible to configure the trusted
  cipher suites for HTTPS through another fw_cfg entry: etc/edk2/https/ciphers.

  -fw_cfg name=etc/edk2/https/ciphers,file=<cipher suites>

  OVMF expects a binary UINT16 array which comprises the cipher suites HEX
  IDs(*4). If the cipher suite list is given, OVMF will choose the cipher
  suite from the intersection of the given list and the built-in cipher
  suites. Otherwise, OVMF just chooses whatever proper cipher suites from the
  built-in ones.

  While the tool(*5) to create the cipher suite array is still under
  development, the array can be generated with the following script:

  export LC_ALL=C
  openssl ciphers -V \
  | sed -r -n \
     -e 's/^ *0x([0-9A-F]{2}),0x([0-9A-F]{2}) - .*$/\\\\x\1 \\\\x\2/p' \
  | xargs -r -- printf -- '%b' > ciphers.bin

  This script creates ciphers.bin that contains all the cipher suite IDs
  supported by openssl according to the local host configuration.

  You may want to enable only a limited set of cipher suites. Then, you
  should check the validity of your list first:

  openssl ciphers -V <cipher list>

  If all the cipher suites in your list map to the proper HEX IDs, go ahead
  to modify the script and execute it:

  export LC_ALL=C
  openssl ciphers -V <cipher list> \
  | sed -r -n \
     -e 's/^ *0x([0-9A-F]{2}),0x([0-9A-F]{2}) - .*$/\\\\x\1 \\\\x\2/p' \
  | xargs -r -- printf -- '%b' > ciphers.bin

* In the future (after release 2.12), QEMU should populate both above fw_cfg
  files automatically from the local host configuration, and enable the user
  to override either with dedicated options or properties.

(*1) See "31.4.1 Signature Database" in UEFI specification 2.7 errata A.
(*2) p11-kit: https://github.com/p11-glue/p11-kit/
(*3) efisiglist: https://github.com/rhboot/pesign/blob/master/src/efisiglist.c
(*4) https://wiki.mozilla.org/Security/Server_Side_TLS#Cipher_names_correspondence_table
(*5) update-crypto-policies: https://gitlab.com/redhat-crypto/fedora-crypto-policies

=== OVMF Flash Layout ===

Like all current IA32/X64 system designs, OVMF's firmware device (rom/flash)
appears in QEMU's physical address space just below 4GB (0x100000000).

OVMF supports building a 1MB, 2MB or 4MB flash image (see the DSC files for the
FD_SIZE_1MB, FD_SIZE_2MB, FD_SIZE_4MB build defines). The base address for the
1MB image in QEMU physical memory is 0xfff00000. The base address for the 2MB
image is 0xffe00000. The base address for the 4MB image is 0xffc00000.

Using the 1MB or 2MB image, the layout of the firmware device in memory looks

+--------------------------------------- 4GB (0x100000000)
| VTF0 (16-bit reset code) and OVMF SEC
| (SECFV, 208KB/0x34000)
+--------------------------------------- varies based on flash size
| Compressed main firmware image
+--------------------------------------- base + 0x20000
| Fault-tolerant write (FTW)
| Spare blocks (64KB/0x10000)
+--------------------------------------- base + 0x10000
| FTW Work block (4KB/0x1000)
+--------------------------------------- base + 0x0f000
| Event log area (4KB/0x1000)
+--------------------------------------- base + 0x0e000
| Non-volatile variable storage
| area (56KB/0xe000)
+--------------------------------------- base address

Using the 4MB image, the layout of the firmware device in memory looks like:

+--------------------------------------- base + 0x400000 (4GB/0x100000000)
| VTF0 (16-bit reset code) and OVMF SEC
| (SECFV, 208KB/0x34000)
+--------------------------------------- base + 0x3cc000
| Compressed main firmware image
| (FVMAIN_COMPACT, 3360KB/0x348000)
+--------------------------------------- base + 0x84000
| Fault-tolerant write (FTW)
| Spare blocks (264KB/0x42000)
+--------------------------------------- base + 0x42000
| FTW Work block (4KB/0x1000)
+--------------------------------------- base + 0x41000
| Event log area (4KB/0x1000)
+--------------------------------------- base + 0x40000
| Non-volatile variable storage
| area (256KB/0x40000)
+--------------------------------------- base address (0xffc00000)

The code in SECFV locates FVMAIN_COMPACT, and decompresses the
main firmware (MAINFV) into RAM memory at address 0x800000. The
remaining OVMF firmware then uses this decompressed firmware
volume image.

=== UNIXGCC Debug ===

If you build with the UNIXGCC toolchain, then debugging will be disabled
due to larger image sizes being produced by the UNIXGCC toolchain. The
first choice recommendation is to use GCC44 or newer instead.

If you must use UNIXGCC, then you can override the build options for
particular libraries and modules in the .dsc to re-enable debugging
selectively. For example:
  OvmfPkg/Library/PlatformBootManagerLib/PlatformBootManagerLib.inf {
      GCC:*_*_*_CC_FLAGS             = -UMDEPKG_NDEBUG
  MdeModulePkg/Universal/BdsDxe/BdsDxe.inf {
      GCC:*_*_*_CC_FLAGS             = -UMDEPKG_NDEBUG

=== UEFI Windows 7 & Windows 2008 Server ===

* One of the '-vga std' and '-vga qxl' QEMU options should be used.
* Only one video mode, 1024x768x32, is supported at OS runtime.
* The '-vga qxl' QEMU option is recommended. After booting the installed
  guest OS, select the video card in Device Manager, and upgrade its driver
  to the QXL XDDM one. Download location:
  <http://www.spice-space.org/download.html>, Guest | Windows binaries.
  This enables further resolutions at OS runtime, and provides S3
  (suspend/resume) capability.