Acidanthera UEFI Development Kit based on EDK II edk2-stable202311
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Laszlo Ersek 39b9a5ffe6 OvmfPkg/PlatformPei: fix MTRR for low-RAM sizes that have many bits clear
Assume that we boot OVMF in a QEMU guest with 1025 MB of RAM. The
following assertion will fire:

> ASSERT_EFI_ERROR (Status = Out of Resources)
> ASSERT OvmfPkg/PlatformPei/MemDetect.c(696): !EFI_ERROR (Status)

That's because the range [1025 MB, 4 GB) that we try to mark as
uncacheable with MTRRs has size 3071 MB:

   0x1_0000_0000
  -0x0_4010_0000
  --------------
   0x0_BFF0_0000

The integer that stands for the uncacheable area size has 11 (eleven) bits
set to 1. As a result, covering this size requires 11 variable MTRRs (each
MTRR must cover a naturally aligned, power-of-two sized area). But, if we
need more variable MTRRs than the CPU can muster (such as 8), then
MtrrSetMemoryAttribute() fails, and we refuse to continue booting (which
is justified, in itself).

Unfortunately, this is not difficult to trigger, and the error message is
well-hidden from end-users, in the OVMF debug log. The following
mitigation is inspired by SeaBIOS:

Truncate the uncacheable area size to a power-of-two, while keeping the
end fixed at 4 GB. Such an interval can be covered by just one variable
MTRR.

This may leave such an MMIO gap, between the end of low-RAM and the start
of the uncacheable area, that is marked as WB (through the MTRR default).
Raise the base of the 32-bit PCI MMIO aperture accordingly -- the gap will
not be used for anything.

On Q35, the minimal 32-bit PCI MMIO aperture (triggered by RAM size 2815
MB) shrinks from

  0xE000_0000 - 0xAFF0_0000 = 769 MB

to

  0xE000_0000 - 0xC000_0000 = 512 MB

On i440fx, the minimal 32-bit PCI MMIO aperture (triggered by RAM size
3583 MB) shrinks from

  0xFC00_0000 - 0xDFF0_0000 = 449 MB

to

  0xFC00_0000 - 0xE000_0000 = 448 MB

Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Cc: Jordan Justen <jordan.l.justen@intel.com>
Ref: https://bugzilla.tianocore.org/show_bug.cgi?id=1814
Ref: https://bugzilla.redhat.com/show_bug.cgi?id=1666941
Ref: https://bugzilla.redhat.com/show_bug.cgi?id=1701710
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Philippe Mathieu-Daude <philmd@redhat.com>
Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
2019-05-16 21:18:58 +02:00
ArmPkg ArmPkg/CompilerIntrinsicsLib: Add uread, uwrite GCC assembly sources 2019-05-13 16:54:38 +01:00
ArmPlatformPkg ArmPlatformPkg: Replace BSD License with BSD+Patent License 2019-04-09 09:10:21 -07:00
ArmVirtPkg ArmVirtPkg: Update DSC/FDF to use NetworkPkg's include fragment file. 2019-05-16 16:45:37 +02:00
BaseTools BaseTools/VfrCompile: clean Framework Vfr support 2019-05-13 09:18:16 +08:00
Conf BaseTools:Delete FrameworkDatabase from BaseTools/Conf 2019-05-09 15:03:30 +08:00
CryptoPkg CryptoPkg/BaseCryptLib: Remove the blank line in the comments 2019-04-29 17:07:12 +08:00
DynamicTablesPkg DynamicTablesPkg: Replace BSD License with BSD+Patent License 2019-04-09 10:57:57 -07:00
EmbeddedPkg EmbeddedPkg/PrePiLib: Drop dependency on IntelFramework[Module]Pkg 2019-05-15 16:31:26 +08:00
EmulatorPkg EmulatorPkg: Update DSC/FDF to use NetworkPkg's include fragment file. 2019-05-16 16:45:38 +02:00
FatPkg FatPkg/FatPei: Remove BootInRecoveryMode PPI DEPEX. 2019-05-09 20:52:40 +08:00
FmpDevicePkg FmpDevicePkg: Replace BSD License with BSD+Patent License 2019-04-09 10:58:00 -07:00
IntelFrameworkModulePkg IntelFrameworkModulePkg: Remove PcdFrameworkCompatibilitySupport usage 2019-05-09 09:42:54 +08:00
IntelFrameworkPkg IntelFrameworkPkg: Replace BSD License with BSD+Patent License 2019-04-09 10:58:02 -07:00
IntelFsp2Pkg IntelFsp2Pkg: Replace BSD License with BSD+Patent License 2019-04-09 10:58:03 -07:00
IntelFsp2WrapperPkg IntelFsp2WrapperPkg/FspWrapperNotifyDxe: make global variable static 2019-04-28 10:54:27 +08:00
IntelFspPkg IntelFspPkg: Replace BSD License with BSD+Patent License 2019-04-09 10:58:04 -07:00
IntelFspWrapperPkg IntelFspWrapperPkg: Replace BSD License with BSD+Patent License 2019-04-09 10:58:05 -07:00
IntelSiliconPkg IntelSiliconPkg/IntelVTdDxe: Do global invalidation before boot 2019-05-10 08:34:45 +08:00
MdeModulePkg MdeModulePkg/Library: Remove BaseUefiTianoCustomDecompressLib 2019-05-15 21:02:59 +08:00
MdePkg MdePkg: Merge TianoCustomDecompress algorithm into 2019-05-15 20:48:26 +08:00
NetworkPkg NetworkPkg: Add package level include DSC file 2019-05-08 16:10:39 +08:00
Nt32Pkg Nt32Pkg: Update DSC/FDF to use NetworkPkg's include fragment file. 2019-05-16 16:29:17 +02:00
OvmfPkg OvmfPkg/PlatformPei: fix MTRR for low-RAM sizes that have many bits clear 2019-05-16 21:18:58 +02:00
PcAtChipsetPkg PcAtChipsetPkg/ResetSystemLib: Add new API ResetSystem 2019-04-28 09:40:18 +08:00
SecurityPkg SecurityPkg/AuthSeriableLib: Always delete variable in certdb 2019-05-15 13:00:37 +08:00
ShellPkg ShellPkg/UefiHandleParsingLib: Remove some unused Guids 2019-04-28 09:50:14 +08:00
SignedCapsulePkg SignedCapsulePkg: Remove PcdFrameworkCompatibilitySupport usage 2019-05-09 09:42:55 +08:00
SourceLevelDebugPkg SourceLevelDebugPkg: Replace BSD License with BSD+Patent License 2019-04-09 10:58:27 -07:00
StandaloneMmPkg StandaloneMmPkg: Replace BSD License with BSD+Patent License 2019-04-09 10:58:27 -07:00
UefiCpuPkg UefiCpuPkg PiSmmCpuDxeSmm: Only support IN/OUT IO save state read (CVE-2018-12182) 2019-05-14 15:54:57 +08:00
UefiPayloadPkg UefiPayloadPkg: Enhance UEFI payload for coreboot and Slim Bootloader 2019-04-15 12:30:05 -07:00
.gitignore edk2: Add .DS_Store to .gitignore for macOS 2017-05-19 15:14:34 -07:00
.gitmodules CryptoPkg: Adding OpenSSL as one submodule of EDKII repo 2018-01-18 14:06:15 +08:00
BuildNotes2.txt BaseTools: Various typo 2019-02-14 10:02:28 +08:00
License-History.txt edk2: Add License-History.txt 2019-04-09 09:10:18 -07:00
License.txt edk2: Change License.txt from 2-Clause BSD to BSD+Patent 2019-04-09 09:10:18 -07:00
Maintainers.txt edk2: Update Maintainers.txt for packages moved to edk2-platforms 2019-05-13 15:58:52 -07:00
Readme.md edk2: Update ReadMe.md and Maintainer.txt for edk2-libc repo 2019-04-29 13:06:59 -07:00
edksetup.bat edk2: Replace BSD License with BSD+Patent License 2019-04-09 09:10:18 -07:00
edksetup.sh Revert "BaseTools:code of test python module is moved to edksetup" 2019-05-09 19:02:35 +08:00

Readme.md

EDK II Project

A modern, feature-rich, cross-platform firmware development environment for the UEFI and PI specifications from www.uefi.org.

The majority of the content in the EDK II open source project uses a BSD-2-Clause Plus Patent License. The EDK II open source project contains the following components that are covered by additional licenses:

The EDK II Project is composed of packages. The maintainers for each package are listed in Maintainers.txt.

Resources

Code Contributions

To make a contribution to a TianoCore project, follow these steps.

  1. Create a change description in the format specified below to use in the source control commit log.

  2. Your commit message must include your Signed-off-by signature

  3. Submit your code to the TianoCore project using the process that the project documents on its web page. If the process is not documented, then submit the code on development email list for the project.

  4. It is preferred that contributions are submitted using the same copyright license as the base project. When that is not possible, then contributions using the following licenses can be accepted:

    For documentation:

    Contributions of code put into the public domain can also be accepted.

    Contributions using other licenses might be accepted, but further review will be required.

Developer Certificate of Origin

Your change description should use the standard format for a commit message, and must include your Signed-off-by signature.

In order to keep track of who did what, all patches contributed must include a statement that to the best of the contributor's knowledge they have the right to contribute it under the specified license.

The test for this is as specified in the Developer's Certificate of Origin (DCO) 1.1. The contributor certifies compliance by adding a line saying

Signed-off-by: Developer Name developer@example.org

where Developer Name is the contributor's real name, and the email address is one the developer is reachable through at the time of contributing.

Developer's Certificate of Origin 1.1

By making a contribution to this project, I certify that:

(a) The contribution was created in whole or in part by me and I
    have the right to submit it under the open source license
    indicated in the file; or

(b) The contribution is based upon previous work that, to the best
    of my knowledge, is covered under an appropriate open source
    license and I have the right under that license to submit that
    work with modifications, whether created in whole or in part
    by me, under the same open source license (unless I am
    permitted to submit under a different license), as indicated
    in the file; or

(c) The contribution was provided directly to me by some other
    person who certified (a), (b) or (c) and I have not modified
    it.

(d) I understand and agree that this project and the contribution
    are public and that a record of the contribution (including all
    personal information I submit with it, including my sign-off) is
    maintained indefinitely and may be redistributed consistent with
    this project or the open source license(s) involved.

Sample Change Description / Commit Message

From: Contributor Name <contributor@example.com>
Subject: [Repository/Branch PATCH] Pkg-Module: Brief-single-line-summary

Full-commit-message

Signed-off-by: Contributor Name <contributor@example.com>

Notes for sample patch email

  • The first line of commit message is taken from the email's subject line following [Repository/Branch PATCH]. The remaining portion of the commit message is the email's content.
  • git format-patch is one way to create this format

Definitions for sample patch email

  • Repository is the identifier of the repository the patch applies. This identifier should only be provided for repositories other than edk2. For example edk2-BuildSpecification or staging.
  • Branch is the identifier of the branch the patch applies. This identifier should only be provided for branches other than edk2/master. For example edk2/UDK2015, edk2-BuildSpecification/release/1.27, or staging/edk2-test.
  • Module is a short identifier for the affected code or documentation. For example MdePkg, MdeModulePkg/UsbBusDxe, Introduction, or EDK II INF File Format.
  • Brief-single-line-summary is a short summary of the change.
  • The entire first line should be less than ~70 characters.
  • Full-commit-message a verbose multiple line comment describing the change. Each line should be less than ~70 characters.
  • Signed-off-by is the contributor's signature identifying them by their real/legal name and their email address.