Acidanthera UEFI Development Kit based on EDK II edk2-stable202311
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Laszlo Ersek 43df61878d OvmfPkg: enable SMM Monarch Election in PiSmmCpuDxeSmm
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>
2020-03-04 12:22:07 +00:00
.azurepipelines .azurepipelines: Enable CI for UnitTestFrameworkPkg and host tests 2020-02-07 19:18:53 +00:00
.mergify .mergify: Add Mergify YML pull request rules configuration file 2019-11-11 13:02:51 -08:00
.pytool .pytool: Add CI support for host based unit tests with results 2020-02-07 19:18:53 +00:00
ArmPkg ArmPkg/ArmSmcPsciResetSystemLib: remove EnterS3WithImmediateWake () 2020-01-14 22:12:17 +00:00
ArmPlatformPkg ArmPlatformPkg/Ds5: Increase path length to 400 2020-02-08 11:51:41 +00:00
ArmVirtPkg ArmVirtPkg: add the 'initrd' dynamic shell command 2020-03-04 09:26:45 +00:00
BaseTools BaseTools: Remove invalid leading space before !INCLUDE in Makefile 2020-03-02 02:36:25 +00:00
Conf BaseTools:Delete FrameworkDatabase from BaseTools/Conf 2019-05-09 15:03:30 +08:00
CryptoPkg CryptoPkg/BaseHashApiLib: Change PcdHashApiLibPolicy type to FixedAtBuild 2020-02-19 16:38:22 +00:00
DynamicTablesPkg DynamicTablesPkg: Arm SRAT Table Generator 2019-10-21 16:16:50 +01:00
EmbeddedPkg EmbeddedPkg/VirtualKeyboard: Fix few typos 2020-02-10 22:30:07 +00:00
EmulatorPkg EmulatorPkg/Win: Fix various typos 2020-02-10 22:30:07 +00:00
FatPkg FatPkg/FatPei: Fix few typos 2020-02-10 22:30:07 +00:00
FmpDevicePkg FmpDevicePkg/FmpDxe: Issues reported by ECC in EDK2. 2020-02-14 07:27:28 +00:00
IntelFsp2Pkg IntelFsp2Pkg/SplitFspBin.py: Coverity scan flags issues. 2020-02-13 09:21:22 +00:00
IntelFsp2WrapperPkg IntelFsp2WrapperPkg: Fix various typos 2019-12-11 01:42:31 +00:00
MdeModulePkg MdeModulePkg/PiSmmCore: log SMM image start failure 2020-03-04 12:22:07 +00:00
MdePkg MdePkg: Remove FIT table industry standard header file. 2020-02-14 04:31:18 +00:00
NetworkPkg NetworkPkg/ArpDxe: Recycle invalid ARP packets (CVE-2019-14559) 2020-02-21 03:01:57 +00:00
OvmfPkg OvmfPkg: enable SMM Monarch Election in PiSmmCpuDxeSmm 2020-03-04 12:22:07 +00:00
PcAtChipsetPkg PcAtChipsetPkg: Fix few typos 2020-02-10 22:30:07 +00:00
SecurityPkg SecurityPkg/DxeImageVerificationLib: change IsCertHashFoundInDatabase name (CVE-2019-14575) 2020-02-19 14:08:23 +00:00
ShellPkg ShellPkg: acpiview: Prevent infinite loop if structure length is 0 2020-02-20 09:27:00 +00:00
SignedCapsulePkg SignedCapsulePkg/Universal: Fix various typos 2020-02-10 22:30:07 +00:00
SourceLevelDebugPkg SourceLevelDebugPkg: Fix few typos 2020-02-10 22:30:07 +00:00
StandaloneMmPkg StandaloneMmPkg: Fix few typos 2020-02-10 22:30:07 +00:00
UefiCpuPkg UefiCpuPkg/PiSmmCpuDxeSmm: fix S3 Resume for CPU hotplug 2020-03-04 12:22:07 +00:00
UefiPayloadPkg UefiPayloadPkg: remove EnterS3WithImmediateWake () from ResetSystemLib 2020-01-10 07:00:51 +00:00
UnitTestFrameworkPkg UnitTestFrameworkPkg: Disable EBC in DSC file 2020-02-11 23:57:44 +00:00
.gitignore .gitignore: Ignore python compiled files, extdeps, and vscode 2019-11-11 13:01:25 -08:00
.gitmodules UnitTestFrameworkPkg/Library: Add library instances 2020-02-07 19:18:53 +00:00
.mailmap .mailmap: Add an entry for Yu-Chen Lin 2020-01-06 18:01:30 +00:00
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 Maintainers.txt: Change NetworkPkg maintainer role. 2020-02-18 13:22:07 +00:00
Readme.md Readme.md: Update EDK II CI build branch name 2019-11-12 03:53:00 +00:00
edksetup.bat edksetup.bat: Simplify the step to use CLANGPDB 2020-01-07 00:44:04 +00:00
edksetup.sh edksetup.sh: remove redundant -?, -h and --help in options parsing 2019-07-23 10:41:55 +02:00
pip-requirements.txt pip-requirements.txt: Add python pip requirements file 2019-11-11 13:01:31 -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.

Build Status

Host Type Toolchain Branch Build Status Test Status Code Coverage
Windows VS2019 master
Ubuntu GCC master

More CI Build information

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:

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.

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.