dd2f74a820
Change 221534 by rwatson@rwatson_zenith_cl_cam_ac_uk on 2013/01/27 16:05:30
FreeBSD/mips stores page-table entries in a near-identical format
to MIPS TLB entries -- only it overrides certain "reserved" bits
in the MIPS-defined EntryLo register to hold software-defined bits
(swbits) to avoid significantly increasing the page table memory
footprint. On n32 and n64, these bits were (a) colliding with
MIPS64r2 physical memory extensions and (b) being improperly
cleared.
Attempt to fix both of these problems by pushing swbits further
along 64-bit EntryLo registers into the reserved space, and
improving consistency between C-based and assembly-based clearing
of swbits -- in particular, to use the same definition. This
should stop swbits from leaking into TLB entries -- while ignored
by most current MIPS hardware, this would cause a problem with
(much) larger physical memory sizes, and also leads to confusing
hardware-level tracing as physical addresses contain unexpected
(and inconsistent) higher bits.
Discussed with: imp, jmallett
Change 1187301 by brooks@brooks_zenith on 2013/10/23 14:40:10
Loop back the initial commit of 221534 to HEAD. Correct its
implementation for mips32.
MFC after: 3 days
Sponsored by: DARPA/AFRL
This is the top level of the FreeBSD source directory. This file was last revised on: $FreeBSD$ 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, the most commonly used one being ``world'', which rebuilds and installs everything in the FreeBSD system from the source tree except the kernel, the kernel-modules and the contents of /etc. The ``world'' target should only be used in cases where the source tree has not changed from the currently running version. See: http://www.freebsd.org/doc/en_US.ISO8859-1/books/handbook/makeworld.html for more information, including setting make(1) variables. The ``buildkernel'' and ``installkernel'' targets build and install the kernel and the modules (see below). Please see the top of the Makefile in this directory for more information on the standard build targets and compile-time flags. Building a kernel is a somewhat more involved process, documentation for which can be found at: http://www.freebsd.org/doc/en_US.ISO8859-1/books/handbook/kernelconfig.html And in the config(8) man page. Note: If you want to build and install the kernel with the ``buildkernel'' and ``installkernel'' targets, you might need to build world before. More information is available in the handbook. The sample kernel configuration files reside in the sys/<arch>/conf sub-directory (assuming that you've installed the kernel sources), the file named GENERIC being the one used to build your initial installation kernel. The file NOTES contains entries and documentation for all possible devices, not just those commonly used. It is the successor of the ancient LINT file, but in contrast to LINT, it is not buildable as a kernel but a pure reference and documentation file. 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. games Amusements. 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. sys Kernel sources. 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: http://www.freebsd.org/doc/en_US.ISO8859-1/books/handbook/synching.html