83e356c3c9
Guest PPC OSs running under a hypervisor may communicate the features they support, in order for the hypervisor to expose a virtualized machine in the way the client (guest OS) expects (see LoPAPR 1.1 - B.6.2.3). This is done by calling the "/ibm,client-architecture-support" (CAS) method, informing supported features in option vectors. Until now, FreeBSD wasn't using CAS, but instead relied on hypervisor/QEMU's defaults. The problem is that, without CAS, it is very inconvenient to run POWER9 VMs on a POWER9 host running with radix enabled. This happens because, in this case, the QEMU default is to present the guest OS a dual MMU (HPT/RPT), instead of presenting a regular HPT MMU, as FreeBSD expects, resulting in an early panic. The known workarounds required either changing the host to disable radix or passing a flag to QEMU to run in a POWER8 compatible mode. With CAS, FreeBSD is now able to communicate that it wants an HPT MMU, independent of the host setup, which now makes FreeBSD work on POWER9/pseries, with KVM enabled and without hugepages (support added in a previous commit). As CAS is invoked through OpenFirmware's call-method interface, it needs to be performed early, when OpenFirmware is still operational. Besides, now that FDT is the default way to inspect the device tree on PPC, OFW call-method feature will be unavailable by default, when control is passed to the kernel. Because of this, the call to CAS is being performed at the loader, instead of at the kernel. To avoid regressions with old platforms, this change uses CAS only on POWER8/POWER9. Reviewed by: jhibbits Differential Revision: https://reviews.freebsd.org/D20827 |
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| bin | ||
| cddl | ||
| contrib | ||
| crypto | ||
| etc | ||
| gnu | ||
| include | ||
| kerberos5 | ||
| lib | ||
| libexec | ||
| release | ||
| rescue | ||
| sbin | ||
| secure | ||
| share | ||
| stand | ||
| sys | ||
| targets | ||
| tests | ||
| tools | ||
| usr.bin | ||
| usr.sbin | ||
| .arcconfig | ||
| .arclint | ||
| .cirrus.yml | ||
| .clang-format | ||
| .gitattributes | ||
| .gitignore | ||
| COPYRIGHT | ||
| LOCKS | ||
| MAINTAINERS | ||
| Makefile | ||
| Makefile.inc1 | ||
| Makefile.libcompat | ||
| Makefile.sys.inc | ||
| ObsoleteFiles.inc | ||
| README | ||
| README.md | ||
| RELNOTES | ||
| UPDATING | ||
FreeBSD Source:
This is the top level of the FreeBSD source directory. This file
was last revised on:
FreeBSD
FreeBSD is an operating system used to power modern servers, desktops, and embedded platforms. A large community has continually developed it for more than thirty years. Its advanced networking, security, and storage features have made FreeBSD the platform of choice for many of the busiest web sites and most pervasive embedded networking and storage devices.
For copyright information, please see the file COPYRIGHT in this directory. Additional copyright information also exists for some sources in this tree - please see the specific source directories for more information.
The Makefile in this directory supports a number of targets for building components (or all) of the FreeBSD source tree. See build(7), config(8), https://www.freebsd.org/doc/en_US.ISO8859-1/books/handbook/makeworld.html, and https://www.freebsd.org/doc/en_US.ISO8859-1/books/handbook/kernelconfig.html for more information, including setting make(1) variables.
Source Roadmap:
bin System/user commands.
cddl Various commands and libraries under the Common Development
and Distribution License.
contrib Packages contributed by 3rd parties.
crypto Cryptography stuff (see crypto/README).
etc Template files for /etc.
gnu Various commands and libraries under the GNU Public License.
Please see gnu/COPYING* for more information.
include System include files.
kerberos5 Kerberos5 (Heimdal) package.
lib System libraries.
libexec System daemons.
release Release building Makefile & associated tools.
rescue Build system for statically linked /rescue utilities.
sbin System commands.
secure Cryptographic libraries and commands.
share Shared resources.
stand Boot loader sources.
sys Kernel sources.
sys/<arch>/conf Kernel configuration files. GENERIC is the configuration
used in release builds. NOTES contains documentation of
all possible entries.
tests Regression tests which can be run by Kyua. See tests/README
for additional information.
tools Utilities for regression testing and miscellaneous tasks.
usr.bin User commands.
usr.sbin System administration commands.
For information on synchronizing your source tree with one or more of the FreeBSD Project's development branches, please see:
https://www.freebsd.org/doc/en_US.ISO8859-1/books/handbook/current-stable.html