43df61878d
With "PcdCpuSmmEnableBspElection" set to FALSE, PiSmmCpuDxeSmm always considers the processor with index 0 to be the SMM Monarch (a.k.a. the SMM BSP). The SMM Monarch handles the SMI for real, while the other CPUs wait in their SMM loops. In a subsequent patch, we want to set "PcdCpuHotPlugSupport" to TRUE. For that, PiCpuSmmEntry() [UefiCpuPkg/PiSmmCpuDxeSmm/PiSmmCpuDxeSmm.c] forces us with an ASSERT() to set "PcdCpuSmmEnableBspElection" to TRUE as well. To satisfy that expectation, we can simply remove our current "PcdCpuSmmEnableBspElection|FALSE" setting, and inherit the default TRUE value from "UefiCpuPkg.dec". This causes "mSmmMpSyncData->BspIndex" in PiSmmCpuDxeSmm to lose its static zero value (standing for CPU#0); instead it becomes (-1) in general, and the SMM Monarch is elected anew on every SMI. The default SMM Monarch Election is basically a race -- whichever CPU can flip "mSmmMpSyncData->BspIndex" from (-1) to its own index, becomes king, for handling that SMI. Refer to SmiRendezvous() [UefiCpuPkg/PiSmmCpuDxeSmm/MpService.c]. I consider this non-determinism less than ideal on QEMU/KVM; it would be nice to stick with a "mostly permanent" SMM Monarch even with the Election enabled. We can do that by implementing the PlatformSmmBspElection() API in the SmmCpuPlatformHookLibQemu instance: The IA32 APIC Base MSR can be read on each CPU concurrently, and it will report the BSP bit as set only on the current Boot Service Processor. QEMU marks CPU#0 as the BSP, by default. Elect the current BSP, as reported by QEMU, for the SMM Monarch role. (Note that the QEMU commit history is not entirely consistent on whether QEMU/KVM may mark a CPU with nonzero index as the BSP: - At tag v4.2.0, "target/i386/cpu.c" has a comment saying "We hard-wire the BSP to the first CPU". This comment goes back to commit 6cb2996cef5e ("x86: Extend validity of bsp_to_cpu", 2010-03-04). - Compare commit 9cb11fd7539b ("target-i386: clear bsp bit when designating bsp", 2015-04-02) though, especially considering KVM. Either way, this OvmfPkg patch is *not* dependent on CPU index 0; it just takes the race on every SMI out of the game.) One benefit of using a "mostly permanent" SMM Monarch / BSP is that we can continue testing the SMM CPU synchronization by deterministically entering the firmware on the BSP, vs. on an AP, from Linux guests: $ time taskset -c 0 efibootmgr $ time taskset -c 1 efibootmgr (See <https://github.com/tianocore/tianocore.github.io/wiki/Testing-SMM-with-QEMU,-KVM-and-libvirt#uefi-variable-access-test>.) Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Igor Mammedov <imammedo@redhat.com> Cc: Jiewen Yao <jiewen.yao@intel.com> Cc: Jordan Justen <jordan.l.justen@intel.com> Cc: Michael Kinney <michael.d.kinney@intel.com> Cc: Philippe Mathieu-Daudé <philmd@redhat.com> Suggested-by: Igor Mammedov <imammedo@redhat.com> Ref: https://bugzilla.tianocore.org/show_bug.cgi?id=1512#c5 Signed-off-by: Laszlo Ersek <lersek@redhat.com> Message-Id: <20200226221156.29589-5-lersek@redhat.com> Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Tested-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> |
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.azurepipelines | ||
.mergify | ||
.pytool | ||
ArmPkg | ||
ArmPlatformPkg | ||
ArmVirtPkg | ||
BaseTools | ||
Conf | ||
CryptoPkg | ||
DynamicTablesPkg | ||
EmbeddedPkg | ||
EmulatorPkg | ||
FatPkg | ||
FmpDevicePkg | ||
IntelFsp2Pkg | ||
IntelFsp2WrapperPkg | ||
MdeModulePkg | ||
MdePkg | ||
NetworkPkg | ||
OvmfPkg | ||
PcAtChipsetPkg | ||
SecurityPkg | ||
ShellPkg | ||
SignedCapsulePkg | ||
SourceLevelDebugPkg | ||
StandaloneMmPkg | ||
UefiCpuPkg | ||
UefiPayloadPkg | ||
UnitTestFrameworkPkg | ||
.gitignore | ||
.gitmodules | ||
.mailmap | ||
License-History.txt | ||
License.txt | ||
Maintainers.txt | ||
Readme.md | ||
edksetup.bat | ||
edksetup.sh | ||
pip-requirements.txt |
Readme.md
EDK II Project
A modern, feature-rich, cross-platform firmware development environment for the UEFI and PI specifications from www.uefi.org.
Build Status
Host Type | Toolchain | Branch | Build Status | Test Status | Code Coverage |
---|---|---|---|---|---|
Windows | VS2019 | master | |||
Ubuntu | GCC | master |
License Details
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:
- BaseTools/Source/C/BrotliCompress
- MdeModulePkg/Library/BrotliCustomDecompressLib
- BaseTools/Source/C/LzmaCompress
- MdeModulePkg/Library/LzmaCustomDecompressLib
- IntelFrameworkModulePkg/Library/LzmaCustomDecompressLib/Sdk
- BaseTools/Source/C/VfrCompile/Pccts
- MdeModulePkg/Universal/RegularExpressionDxe/Oniguruma
- OvmfPkg
- CryptoPkg/Library/OpensslLib/openssl
- ArmPkg/Library/ArmSoftFloatLib/berkeley-softfloat-3
The EDK II Project is composed of packages. The maintainers for each package are listed in Maintainers.txt.
Resources
- TianoCore
- EDK II
- Getting Started with EDK II
- Mailing Lists
- TianoCore Bugzilla
- How To Contribute
- Release Planning
Code Contributions
To make a contribution to a TianoCore project, follow these steps.
-
Create a change description in the format specified below to use in the source control commit log.
-
Your commit message must include your
Signed-off-by
signature -
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.
-
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:
- BSD (2-clause): http://opensource.org/licenses/BSD-2-Clause
- BSD (3-clause): http://opensource.org/licenses/BSD-3-Clause
- MIT: http://opensource.org/licenses/MIT
- Python-2.0: http://opensource.org/licenses/Python-2.0
- Zlib: http://opensource.org/licenses/Zlib
For documentation:
- FreeBSD Documentation License https://www.freebsd.org/copyright/freebsd-doc-license.html
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 thanedk2
. For exampleedk2-BuildSpecification
orstaging
.Branch
is the identifier of the branch the patch applies. This identifier should only be provided for branches other thanedk2/master
. For exampleedk2/UDK2015
,edk2-BuildSpecification/release/1.27
, orstaging/edk2-test
.Module
is a short identifier for the affected code or documentation. For exampleMdePkg
,MdeModulePkg/UsbBusDxe
,Introduction
, orEDK 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.
Submodules
Submodule in EDK II is allowed but submodule chain should be avoided as possible as we can. Currently EDK II contains the following submodules
- CryptoPkg/Library/OpensslLib/openssl
- ArmPkg/Library/ArmSoftFloatLib/berkeley-softfloat-3
ArmSoftFloatLib is actually required by OpensslLib. It's inevitable in openssl-1.1.1 (since stable201905) for floating point parameter conversion, but should be dropped once there's no such need in future release of openssl.
To get a full, buildable EDK II repository, use following steps of git command
$ git clone https://github.com/tianocore/edk2.git
$ cd edk2
$ git submodule update --init
$ cd ..
If there's update for submodules, use following git commands to get the latest submodules code.
$ cd edk2
$ git pull
$ git submodule update
Note: When cloning submodule repos, '--recursive' option is not recommended. EDK II itself will not use any code/feature from submodules in above submodules. So using '--recursive' adds a dependency on being able to reach servers we do not actually want any code from, as well as needlessly downloading code we will not use.