mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/
synced 2026-10-16 22:39:48 +00:00
No description
- C 96.9%
- Assembly 0.9%
- Rust 0.6%
- Shell 0.6%
- Python 0.5%
- Other 0.3%
7f70c3815a
Protected Execution Facility (PEF) is an architectural change for
POWER 9 that enables Secure Virtual Machines (SVMs). When enabled,
PEF adds a new higher privileged mode, called Ultravisor mode, to
POWER architecture.
The hardware changes include the following:
* There is a new bit in the MSR that determines whether the current
process is running in secure mode, MSR(S) bit 41. MSR(S)=1, process
is in secure mode, MSR(s)=0 process is in normal mode.
* The MSR(S) bit can only be set by the Ultravisor.
* HRFID cannot be used to set the MSR(S) bit. If the hypervisor needs
to return to a SVM it must use an ultracall. It can determine if
the VM it is returning to is secure.
* The privilege of a process is now determined by three MSR bits,
MSR(S, HV, PR). In each of the tables below the modes are listed
from least privilege to highest privilege. The higher privilege
modes can access all the resources of the lower privilege modes.
**Secure Mode MSR Settings**
+---+---+---+---------------+
| S | HV| PR|Privilege |
+===+===+===+===============+
| 1 | 0 | 1 | Problem |
+---+---+---+---------------+
| 1 | 0 | 0 | Privileged(OS)|
+---+---+---+---------------+
| 1 | 1 | 0 | Ultravisor |
+---+---+---+---------------+
| 1 | 1 | 1 | Reserved |
+---+---+---+---------------+
**Normal Mode MSR Settings**
+---+---+---+---------------+
| S | HV| PR|Privilege |
+===+===+===+===============+
| 0 | 0 | 1 | Problem |
+---+---+---+---------------+
| 0 | 0 | 0 | Privileged(OS)|
+---+---+---+---------------+
| 0 | 1 | 0 | Hypervisor |
+---+---+---+---------------+
| 0 | 1 | 1 | Problem (HV) |
+---+---+---+---------------+
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Signed-off-by: Ram Pai <linuxram@us.ibm.com>
[ cclaudio: Update the commit message ]
Signed-off-by: Claudio Carvalho <cclaudio@linux.ibm.com>
Signed-off-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190820021326.6884-7-bauerman@linux.ibm.com
|
History
|
|
|---|---|---|
| arch | ||
| block | ||
| certs | ||
| crypto | ||
| Documentation | ||
| drivers | ||
| fs | ||
| include | ||
| init | ||
| ipc | ||
| kernel | ||
| lib | ||
| LICENSES | ||
| mm | ||
| net | ||
| samples | ||
| scripts | ||
| security | ||
| sound | ||
| tools | ||
| usr | ||
| virt | ||
| .clang-format | ||
| .cocciconfig | ||
| .get_maintainer.ignore | ||
| .gitattributes | ||
| .gitignore | ||
| .mailmap | ||
| COPYING | ||
| CREDITS | ||
| Kbuild | ||
| Kconfig | ||
| MAINTAINERS | ||
| Makefile | ||
| README | ||
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.