Linus Torvalds 249872f53d Merge tag 'tsm-for-6.19' of git://git.kernel.org/pub/scm/linux/kernel/git/devsec/tsm
Pull PCIe Link Encryption and Device Authentication from Dan Williams:
 "New PCI infrastructure and one architecture implementation for PCIe
  link encryption establishment via platform firmware services.

  This work is the result of multiple vendors coming to consensus on
  some core infrastructure (thanks Alexey, Yilun, and Aneesh!), and
  three vendor implementations, although only one is included in this
  pull. The PCI core changes have an ack from Bjorn, the crypto/ccp/
  changes have an ack from Tom, and the iommu/amd/ changes have an ack
  from Joerg.

  PCIe link encryption is made possible by the soup of acronyms
  mentioned in the shortlog below. Link Integrity and Data Encryption
  (IDE) is a protocol for installing keys in the transmitter and
  receiver at each end of a link. That protocol is transported over Data
  Object Exchange (DOE) mailboxes using PCI configuration requests.

  The aspect that makes this a "platform firmware service" is that the
  key provisioning and protocol is coordinated through a Trusted
  Execution Envrionment (TEE) Security Manager (TSM). That is either
  firmware running in a coprocessor (AMD SEV-TIO), or quasi-hypervisor
  software (Intel TDX Connect / ARM CCA) running in a protected CPU
  mode.

  Now, the only reason to ask a TSM to run this protocol and install the
  keys rather than have a Linux driver do the same is so that later, a
  confidential VM can ask the TSM directly "can you certify this
  device?".

  That precludes host Linux from provisioning its own keys, because host
  Linux is outside the trust domain for the VM. It also turns out that
  all architectures, save for one, do not publish a mechanism for an OS
  to establish keys in the root port. So "TSM-established link
  encryption" is the only cross-architecture path for this capability
  for the foreseeable future.

  This unblocks the other arch implementations to follow in v6.20/v7.0,
  once they clear some other dependencies, and it unblocks the next
  phase of work to implement the end-to-end flow of confidential device
  assignment. The PCIe specification calls this end-to-end flow Trusted
  Execution Environment (TEE) Device Interface Security Protocol
  (TDISP).

  In the meantime, Linux gets a link encryption facility which has
  practical benefits along the same lines as memory encryption. It
  authenticates devices via certificates and may protect against
  interposer attacks trying to capture clear-text PCIe traffic.

  Summary:

   - Introduce the PCI/TSM core for the coordination of device
     authentication, link encryption and establishment (IDE), and later
     management of the device security operational states (TDISP).
     Notify the new TSM core layer of PCI device arrival and departure

   - Add a low level TSM driver for the link encryption establishment
     capabilities of the AMD SEV-TIO architecture

   - Add a library of helpers TSM drivers to use for IDE establishment
     and the DOE transport

   - Add skeleton support for 'bind' and 'guest_request' operations in
     support of TDISP"

* tag 'tsm-for-6.19' of git://git.kernel.org/pub/scm/linux/kernel/git/devsec/tsm: (23 commits)
  crypto/ccp: Fix CONFIG_PCI=n build
  virt: Fix Kconfig warning when selecting TSM without VIRT_DRIVERS
  crypto/ccp: Implement SEV-TIO PCIe IDE (phase1)
  iommu/amd: Report SEV-TIO support
  psp-sev: Assign numbers to all status codes and add new
  ccp: Make snp_reclaim_pages and __sev_do_cmd_locked public
  PCI/TSM: Add 'dsm' and 'bound' attributes for dependent functions
  PCI/TSM: Add pci_tsm_guest_req() for managing TDIs
  PCI/TSM: Add pci_tsm_bind() helper for instantiating TDIs
  PCI/IDE: Initialize an ID for all IDE streams
  PCI/IDE: Add Address Association Register setup for downstream MMIO
  resource: Introduce resource_assigned() for discerning active resources
  PCI/TSM: Drop stub for pci_tsm_doe_transfer()
  drivers/virt: Drop VIRT_DRIVERS build dependency
  PCI/TSM: Report active IDE streams
  PCI/IDE: Report available IDE streams
  PCI/IDE: Add IDE establishment helpers
  PCI: Establish document for PCI host bridge sysfs attributes
  PCI: Add PCIe Device 3 Extended Capability enumeration
  PCI/TSM: Establish Secure Sessions and Link Encryption
  ...
2025-12-06 10:15:41 -08:00
2022-09-28 09:02:20 +02:00
2025-02-19 14:53:27 -07:00

Linux kernel
============

The Linux kernel is the core of any Linux operating system. It manages hardware,
system resources, and provides the fundamental services for all other software.

Quick Start
-----------

* Report a bug: See Documentation/admin-guide/reporting-issues.rst
* Get the latest kernel: https://kernel.org
* Build the kernel: See Documentation/admin-guide/quickly-build-trimmed-linux.rst
* Join the community: https://lore.kernel.org/

Essential Documentation
-----------------------

All users should be familiar with:

* Building requirements: Documentation/process/changes.rst
* Code of Conduct: Documentation/process/code-of-conduct.rst
* License: See COPYING

Documentation can be built with make htmldocs or viewed online at:
https://www.kernel.org/doc/html/latest/


Who Are You?
============

Find your role below:

* New Kernel Developer - Getting started with kernel development
* Academic Researcher - Studying kernel internals and architecture
* Security Expert - Hardening and vulnerability analysis
* Backport/Maintenance Engineer - Maintaining stable kernels
* System Administrator - Configuring and troubleshooting
* Maintainer - Leading subsystems and reviewing patches
* Hardware Vendor - Writing drivers for new hardware
* Distribution Maintainer - Packaging kernels for distros


For Specific Users
==================

New Kernel Developer
--------------------

Welcome! Start your kernel development journey here:

* Getting Started: Documentation/process/development-process.rst
* Your First Patch: Documentation/process/submitting-patches.rst
* Coding Style: Documentation/process/coding-style.rst
* Build System: Documentation/kbuild/index.rst
* Development Tools: Documentation/dev-tools/index.rst
* Kernel Hacking Guide: Documentation/kernel-hacking/hacking.rst
* Core APIs: Documentation/core-api/index.rst

Academic Researcher
-------------------

Explore the kernel's architecture and internals:

* Researcher Guidelines: Documentation/process/researcher-guidelines.rst
* Memory Management: Documentation/mm/index.rst
* Scheduler: Documentation/scheduler/index.rst
* Networking Stack: Documentation/networking/index.rst
* Filesystems: Documentation/filesystems/index.rst
* RCU (Read-Copy Update): Documentation/RCU/index.rst
* Locking Primitives: Documentation/locking/index.rst
* Power Management: Documentation/power/index.rst

Security Expert
---------------

Security documentation and hardening guides:

* Security Documentation: Documentation/security/index.rst
* LSM Development: Documentation/security/lsm-development.rst
* Self Protection: Documentation/security/self-protection.rst
* Reporting Vulnerabilities: Documentation/process/security-bugs.rst
* CVE Procedures: Documentation/process/cve.rst
* Embargoed Hardware Issues: Documentation/process/embargoed-hardware-issues.rst
* Security Features: Documentation/userspace-api/seccomp_filter.rst

Backport/Maintenance Engineer
-----------------------------

Maintain and stabilize kernel versions:

* Stable Kernel Rules: Documentation/process/stable-kernel-rules.rst
* Backporting Guide: Documentation/process/backporting.rst
* Applying Patches: Documentation/process/applying-patches.rst
* Subsystem Profile: Documentation/maintainer/maintainer-entry-profile.rst
* Git for Maintainers: Documentation/maintainer/configure-git.rst

System Administrator
--------------------

Configure, tune, and troubleshoot Linux systems:

* Admin Guide: Documentation/admin-guide/index.rst
* Kernel Parameters: Documentation/admin-guide/kernel-parameters.rst
* Sysctl Tuning: Documentation/admin-guide/sysctl/index.rst
* Tracing/Debugging: Documentation/trace/index.rst
* Performance Security: Documentation/admin-guide/perf-security.rst
* Hardware Monitoring: Documentation/hwmon/index.rst

Maintainer
----------

Lead kernel subsystems and manage contributions:

* Maintainer Handbook: Documentation/maintainer/index.rst
* Pull Requests: Documentation/maintainer/pull-requests.rst
* Managing Patches: Documentation/maintainer/modifying-patches.rst
* Rebasing and Merging: Documentation/maintainer/rebasing-and-merging.rst
* Development Process: Documentation/process/maintainer-handbooks.rst
* Maintainer Entry Profile: Documentation/maintainer/maintainer-entry-profile.rst
* Git Configuration: Documentation/maintainer/configure-git.rst

Hardware Vendor
---------------

Write drivers and support new hardware:

* Driver API Guide: Documentation/driver-api/index.rst
* Driver Model: Documentation/driver-api/driver-model/driver.rst
* Device Drivers: Documentation/driver-api/infrastructure.rst
* Bus Types: Documentation/driver-api/driver-model/bus.rst
* Device Tree Bindings: Documentation/devicetree/bindings/
* Power Management: Documentation/driver-api/pm/index.rst
* DMA API: Documentation/core-api/dma-api.rst

Distribution Maintainer
-----------------------

Package and distribute the kernel:

* Stable Kernel Rules: Documentation/process/stable-kernel-rules.rst
* ABI Documentation: Documentation/ABI/README
* Kernel Configuration: Documentation/kbuild/kconfig.rst
* Module Signing: Documentation/admin-guide/module-signing.rst
* Kernel Parameters: Documentation/admin-guide/kernel-parameters.rst
* Tainted Kernels: Documentation/admin-guide/tainted-kernels.rst



Communication and Support
=========================

* Mailing Lists: https://lore.kernel.org/
* IRC: #kernelnewbies on irc.oftc.net
* Bugzilla: https://bugzilla.kernel.org/
* MAINTAINERS file: Lists subsystem maintainers and mailing lists
* Email Clients: Documentation/process/email-clients.rst
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