232d0b87e0
- Explicitly load an empty initial state into FP registers when taking the fault on the first FP instruction in a thread. Setting SSTATE.FS to INITIAL is just a marker to let context switch restore code know that it can load FP registers with zeroes instead of memory loads. It does not imply that the hardware will reset all registers to zero on first access. In addition, set the state to CLEAN instead of INITIAL after the first FP instruction. cpu_switch() doesn't do anything for INITIAL and only restores from the pcb if the state is CLEAN. We could perhaps change cpu_switch to call fpe_state_clear if the state was INITIAL and leave SSTATE.FS set to INITIAL instead of CLEAN after the first FP instruction. However, adding this complexity to cpu_switch() doesn't seem worth the supposed gain. - Only save the current FPU registers in fill_fpregs() if the request is made to save the current thread's registers. Previously if a debugger requested FP registers via ptrace() it was getting a copy of the debugger's FP registers rather than the debugee's. - Zero the entire FP register set structure returned for ptrace() if a thread hasn't used FP registers rather than leaking garbage in the fp_fcsr field. - If a debugger writes FP registers via ptrace(), always mark the pcb as having valid FP registers and set SSTATUS.FS_MASK to CLEAN so that the registers will be restored when the debugged thread resumes. - Be more explicit about clearing the SSTATUS.FS field before setting it to CLEAN on the first FP instruction trap. Submitted by: br, markj Approved by: re (rgrimes) Sponsored by: DARPA Differential Revision: https://reviews.freebsd.org/D17141 |
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| 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 | ||
| .gitattributes | ||
| .gitignore | ||
| COPYRIGHT | ||
| LOCKS | ||
| MAINTAINERS | ||
| Makefile | ||
| Makefile.inc1 | ||
| Makefile.libcompat | ||
| Makefile.sys.inc | ||
| ObsoleteFiles.inc | ||
| README | ||
| README.md | ||
| 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