release/doc/en_US.ISO8859-1/relnotes/article.xml

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   4 <!ENTITY % release PUBLIC "-//FreeBSD//ENTITIES Release Specification//EN" "release.ent">
   5  %release;
   6 <!ENTITY % sponsor PUBLIC "-//FreeBSD//ENTITIES Sponsor Specification//EN" "sponsor.ent">
   7  %sponsor;
   8 <!ENTITY % vendor PUBLIC "-//FreeBSD//ENTITIES Vendor Specification//EN" "vendor.ent">
   9  %vendor;
  10 <!ENTITY security SYSTEM "../../share/xml/security.xml">
  11 <!ENTITY errata SYSTEM "../../share/xml/errata.xml">
  12 ]>
  13 <article xmlns="http://docbook.org/ns/docbook"
  14   xmlns:xlink="http://www.w3.org/1999/xlink" version="5.0">
  15
  16   <info>
  17     <title>&os; &release.current; Release Notes</title>
  18
  19     <author>
  20       <orgname>The &os; Project</orgname>
  21     </author>
  22
  23     <pubdate>$FreeBSD$</pubdate>
  24
  25     <!-- Last rev: 282482 -->
  26
  27     <copyright>
  28       <year>2015</year>
  29       <holder role="mailto:doc@FreeBSD.org">The &os; Documentation
  30         Project</holder>
  31     </copyright>
  32
  33     <legalnotice xml:id="trademarks" role="trademarks">
  34       &tm-attrib.freebsd;
  35       &tm-attrib.ibm;
  36       &tm-attrib.ieee;
  37       &tm-attrib.intel;
  38       &tm-attrib.sparc;
  39       &tm-attrib.general;
  40     </legalnotice>
  41
  42     <abstract>
  43       <para>The release notes for &os; &release.current; contain
  44         a summary of the changes made to the &os; base system on the
  45         &release.branch; development line.  This document lists
  46         applicable security advisories that were issued since the last
  47         release, as well as significant changes to the &os; kernel and
  48         userland.  Some brief remarks on upgrading are also
  49         presented.</para>
  50     </abstract>
  51   </info>
  52
  53   <sect1 xml:id="intro">
  54     <title>Introduction</title>
  55
  56     <para>This document contains the release notes for &os;
  57       &release.current;.  It describes recently added, changed, or
  58       deleted features of &os;.  It also provides some notes on
  59       upgrading from previous versions of &os;.</para>
  60
  61     <para releasetype="current">The &release.type; distribution to
  62       which these release notes apply represents the latest point
  63       along the &release.branch; development branch since
  64       &release.branch; was created.  Information regarding pre-built,
  65       binary &release.type; distributions along this branch can be
  66       found at <uri
  67         xlink:href="&release.url;">&release.url;</uri>.</para>
  68
  69     <para releasetype="snapshot">The &release.type; distribution to
  70       which these release notes apply represents a point along the
  71       &release.branch; development branch between &release.prev; and
  72       the future &release.next;.  Information regarding pre-built,
  73       binary &release.type; distributions along this branch can be
  74       found at <uri
  75         xlink:href="&release.url;">&release.url;</uri>.</para>
  76
  77     <para releasetype="release">This distribution of &os;
  78       &release.current; is a &release.type; distribution.  It can be
  79       found at <uri xlink:href="&release.url;">&release.url;</uri> or
  80       any of its mirrors.  More information on obtaining this (or
  81       other) &release.type; distributions of &os; can be found in the
  82       <link
  83         xlink:href="&url.books.handbook;/mirrors.html"><quote>Obtaining
  84           &os;</quote> appendix</link> to the <link
  85         xlink:href="&url.books.handbook;/">&os;
  86         Handbook</link>.</para>
  87
  88     <para>All users are encouraged to consult the release errata
  89       before installing &os;.  The errata document is updated with
  90       <quote>late-breaking</quote> information discovered late in the
  91       release cycle or after the release.  Typically, it contains
  92       information on known bugs, security advisories, and corrections
  93       to documentation.  An up-to-date copy of the errata for &os;
  94       &release.current; can be found on the &os; Web site.</para>
  95
  96     <para>This document describes the most user-visible new or changed
  97       features in &os; since &release.prev;.  In general, changes
  98       described here are unique to the &release.branch; branch unless
  99       specifically marked as &merged; features.</para>
 100
 101     <para>Typical release note items document recent security
 102       advisories issued after &release.prev;, new drivers or hardware
 103       support, new commands or options, major bug fixes, or
 104       contributed software upgrades.  They may also list changes to
 105       major ports/packages or release engineering practices.  Clearly
 106       the release notes cannot list every single change made to &os;
 107       between releases; this document focuses primarily on security
 108       advisories, user-visible changes, and major architectural
 109       improvements.</para>
 110   </sect1>
 111
 112   <sect1 xml:id="upgrade">
 113     <title>Upgrading from Previous Releases of &os;</title>
 114
 115     <para arch="amd64,i386">Binary upgrades between RELEASE versions
 116       (and snapshots of the various security branches) are supported
 117       using the &man.freebsd-update.8; utility.  The binary upgrade
 118       procedure will update unmodified userland utilities, as well as
 119       unmodified GENERIC kernels distributed as a part of an official
 120       &os; release.  The &man.freebsd-update.8; utility requires that
 121       the host being upgraded have Internet connectivity.</para>
 122
 123     <para>Source-based upgrades (those based on recompiling the &os;
 124       base system from source code) from previous versions are
 125       supported, according to the instructions in
 126       <filename>/usr/src/UPDATING</filename>.</para>
 127
 128     <important>
 129       <para>Upgrading &os; should only be attempted after backing up
 130         <emphasis>all</emphasis> data and configuration files.</para>
 131     </important>
 132   </sect1>
 133
 134   <sect1 xml:id="security-errata">
 135     <title>Security and Errata</title>
 136
 137     <para>This section lists the various Security Advisories and
 138       Errata Notices since &release.prev;.</para>
 139
 140     <sect2 xml:id="security">
 141       <title>Security Advisories</title>
 142
 143       &security;
 144     </sect2>
 145
 146     <sect2 xml:id="errata">
 147       <title>Errata Notices</title>
 148
 149       &errata;
 150     </sect2>
 151   </sect1>
 152
 153   <sect1 xml:id="userland">
 154     <title>Userland</title>
 155
 156     <para>This section covers changes and additions to userland
 157       applications, contributed software, and system utilities.</para>
 158
 159     <sect2 xml:id="userland-config">
 160       <title>Userland Configuration Changes</title>
 161
 162       <para revision="266463">The default &man.newsyslog.conf.5; now
 163         includes files in the
 164         <filename>/etc/newsyslog.conf.d/</filename> and
 165         <filename>/usr/local/etc/newsyslog.conf.d/</filename>
 166         directories by default for &man.newsyslog.8;.</para>
 167
 168       <para revision="270675">The &man.mailwrapper.8; utility has been
 169         updated to use &man.mailer.conf.5; from the
 170         <literal>LOCALBASE</literal> environment variable, which
 171         defaults to <filename class="directory">/usr/local</filename>
 172         if unset.</para>
 173
 174       <para revision="272350">The <literal>MK_ARM_EABI</literal>
 175         &man.src.conf.5; option has been removed.</para>
 176     </sect2>
 177
 178     <sect2 xml:id="userland-programs">
 179       <title>Userland Application Changes</title>
 180
 181       <para revision="258838" contrib="sponsor" sponsor="&ff;,
 182         &google;" sponsorurl="">The &man.casperd.8; daemon has been
 183         added, which provides access to functionality that is not
 184         available in the <quote>capability mode</quote>
 185         sandbox.</para>
 186
 187       <para revision="260594">When unable to load a kernel module with
 188         &man.kldload.8;, a message informing to view output of
 189         &man.dmesg.8; is now printed, opposed to the previous output
 190         <quote>Exec format error.</quote>.</para>
 191
 192       <para revision="260910">Allow &man.pciconf.8; to identify PCI
 193         devices that are attached to a driver to be identified by
 194         their device name instead of just the selector.  Additionally,
 195         an optional device argument to the <literal>-l</literal> flag
 196         to restrict the output to only listing details about a single
 197         device.</para>
 198
 199       <para revision="260913">A new flag, <quote>onifconsole</quote>
 200         has been added to <filename>/etc/ttys</filename>.  This allows
 201         the system to provide a login prompt via serial console if the
 202         device is an active kernel console, otherwise it is equivalent
 203         to <literal>off</literal>.</para>
 204
 205       <para revision="260926">Support for displaying VPD for PCI
 206         devices via &man.pciconf.8; has been added.</para>
 207
 208       <para revision="261498">&man.ping.8; protects against malicious
 209         network packets using the Capsicum framework to drop
 210         privileges.</para>
 211
 212       <para revision="265229">The &man.ps.1; utility has been
 213         updated to include the <literal>-J</literal> flag, used to
 214         filter output by matching &man.jail.8; IDs and names.
 215         Additionally, argument <literal>0</literal> can be used to
 216         <literal>-J</literal> to only list processes running on the
 217         host system.</para>
 218
 219       <para revision="265249">The &man.top.1; utility has been updated
 220         to filter by &man.jail.8; ID or name, in followup to the
 221         &man.ps.1; change in <literal>r265229</literal>.</para>
 222
 223       <para revision="265995">The Blowfish &man.crypt.3; default
 224         format has been changed to
 225         <literal>&dollar;2b&dollar;</literal>.</para>
 226
 227       <para revision="266209">The &man.pmcstat.8; utility has been
 228         updated to include a new flag, <literal>-l</literal>, which
 229         ends event collection after the specified number of
 230         seconds.</para>
 231
 232       <para revision="270745">The &man.ps.1; utility has been updated
 233         to include a new keyword, <quote>tracer</quote>, which
 234         displays the <acronym>PID</acronym> of the tracing
 235         process.</para>
 236
 237       <para revision="271482">Support for adding empty partitions has
 238         been added to the &man.mkimg.1; utility.</para>
 239
 240       <para revision="272166">The &man.primes.6; utility has been
 241         updated to correctly enumerate prime numbers between
 242         <literal>4295098369</literal> and
 243         <literal>3825123056546413050</literal>, which prior to this
 244         change, it would be possible for returned values to be
 245         incorrectly identified as prime numbers.</para>
 246
 247       <para revision="272198">The &man.mkimg.1; utility has been
 248         updated to include three options used to print information
 249         about &man.mkimg.1; itself:</para>
 250
 251       <informaltable frame="none" pgwide="0">
 252         <tgroup cols="2">
 253           <colspec colwidth="1*"/>
 254           <colspec colwidth="1*"/>
 255           <thead>
 256             <row>
 257               <entry>Option</entry>
 258               <entry>Output</entry>
 259             </row>
 260           </thead>
 261
 262           <tbody>
 263             <row>
 264               <entry><literal>--version</literal></entry>
 265               <entry>The current version of the &man.mkimg.1;
 266                 utility</entry>
 267             </row>
 268
 269             <row>
 270               <entry><literal>--formats</literal></entry>
 271               <entry>The disk image file formats supported by
 272                 &man.mkimg.1;</entry>
 273             </row>
 274
 275             <row>
 276               <entry><literal>--schemes</literal></entry>
 277               <entry>The partition schemes supported by
 278                 &man.mkimg.1;</entry>
 279             </row>
 280           </tbody>
 281         </tgroup>
 282       </informaltable>
 283
 284       <para revision="272488">Userland &man.ctf.5; support in
 285         &man.dtrace.1; has been added.  With this change,
 286         &man.dtrace.1; is able to resolve type info for function and
 287         <acronym>USDT</acronym> probe arguments, and function return
 288         values.</para>
 289
 290       <para revision="274960">The &man.elfdump.1; utility has been
 291         updated to support capability mode provided by
 292         &man.capsicum.4;.</para>
 293
 294       <para revision="275680" contrib="sponsor" sponsor="&ff;">The
 295         &man.fstyp.8; utility has been added, which is used to
 296         determine the filesystem on a specified device.</para>
 297
 298       <para revision="276881">The <literal>libedit</literal> library
 299         has been updated to support <acronym>UTF</acronym>-8, which
 300         additionally provides unicode support to &man.sh.1;.</para>
 301
 302       <para revision="277166" arch="powerpc">The &man.ptrace.2; system
 303         call has been updated include support for Altivec registers on
 304         &os;/&arch.powerpc;.</para>
 305
 306       <para revision="278320">A new device control utility,
 307         &man.devctl.8; has been added, which allows making
 308         administrative changes to individual devices, such as
 309         attaching and detaching drivers, and enabling and disabling
 310         devices.  The &man.devctl.8; utility uses the new
 311         &man.devctl.3; library.</para>
 312
 313       <para revision="279315" contrib="sponsor" sponsor="&ff;">The
 314         &man.uefisign.8; utility has been added.</para>
 315
 316       <para revision="279571" contrib="sponsor"
 317         sponsor="&scaleengine;">The &man.freebsd-update.8; utility has
 318         been updated to prevent fetching updated binary patches when
 319         a previous upgrade has not been thoroughly completed.</para>
 320
 321       <para revision="279122" contrib="sponsor"
 322         sponsor="&juniper;">The &man.netstat.1; utility has been
 323         updated to link against the &man.libxo.3; shared
 324         library.</para>
 325
 326       <para revision="280870">A regression in the &man.libarchive.3;
 327         library that would prevent a directory from being included in
 328         the archive when <literal>--one-file-system</literal> is used
 329         has been fixed.</para>
 330
 331       <para revision="281311" contrib="sponsor" sponsor="&ff;">The
 332         &man.ar.1; utility has been updated to set
 333         <literal>ARCHIVE_EXTRACT_SECURE_SYMLINKS</literal> and
 334         <literal>ARCHIVE_EXTRACT_SECURE_NODOTDOT</literal> to disallow
 335         directory traversal when extracting an archive, similar to
 336         &man.tar.1;.</para>
 337
 338       <para revision="282208" contrib="sponsor"
 339         sponsor="&multiplay;">The &man.chflags.1;, &man.chgrp.1;,
 340         &man.chmod.1;, and &man.chown.8; utilities now affect symbolic
 341         links when the <literal>-R</literal> flag is specified, as
 342         documented in &man.symlink.7;.</para>
 343
 344       <para revision="281617">A race condition in &man.wc.1; that
 345         would cause final results to be sent to &man.stderr.4; when
 346         receiving the <literal>SIGINFO</literal> signal has been
 347         fixed.</para>
 348     </sect2>
 349
 350     <sect2 xml:id="userland-contrib">
 351       <title>Contributed Software</title>
 352
 353       <para revision="258884" contrib="sponsor"
 354         sponsor="&darpa_afrl;">&man.lldb.1; has been updated to
 355         upstream snapshot version r196259.</para>
 356
 357       <para revision="259626">Timezone data files have been updated to
 358         version 2013i.</para>
 359
 360       <para revision="260445">&man.byacc.1; has been updated to
 361         version 20140101.</para>
 362
 363       <para revision="261071">&man.jemalloc.3; has been updated to
 364         version 3.5.0.</para>
 365
 366       <para revision="261283"><application>libc++</application> has
 367         been updated to version 3.4.</para>
 368
 369       <para revision="261320"><application>OpenSSH</application> has
 370         been updated to 6.5p1.</para>
 371
 372       <para revision="261344"><application>mdocml</application> has
 373         been updated to version 1.12.3.</para>
 374
 375       <para revision="261991"><application>LLVM</application> and
 376         <application>Clang</application> have been updated to
 377         version 3.4.</para>
 378
 379       <para revision="266527"
 380         role="merged"><application>Sendmail</application> has been
 381         updated from 8.14.7 to 8.14.9.</para>
 382
 383       <para revision="276577"><application>file</application> has been
 384         updated to version 5.22.</para>
 385
 386       <para revision="275718">The <application>binutils</application>
 387         suite of utilities has been updated to include upstream
 388         patches that add new relocations for &arch.powerpc;
 389         support.</para>
 390
 391       <para revision="276398" contrib="sponsor" sponsor="&ff;">The
 392         <application>ELF Tool Chain</application> has been updated to
 393         upstream revision r3136.</para>
 394
 395       <para revision="276551">The <application>texinfo</application>
 396         utility and <literal>info</literal> pages were removed from
 397         the base system.  The <filename
 398           role="package">print/texinfo</filename> port should be
 399         installed on systems where <literal>info</literal> pages are
 400         needed.</para>
 401
 402       <para revision="276796" contrib="sponsor" sponsor="&ff;">The ELF
 403         object manipulation tools
 404         <application>addr2line</application>,
 405         <application>elfcopy (strip)</application>,
 406         <application>nm</application>,
 407         <application>readelf</application>,
 408         <application>size</application>, and
 409         <application>strings</application> were switched to the
 410         versions from the ELF Tool Chain project.</para>
 411
 412       <para revision="276881">The <literal>libedit</literal> library
 413         has been updated to include <acronym>UTF-8</acronym> support,
 414         adding <acronym>UTF-8</acronym> support to the &man.sh.1;
 415         shell.</para>
 416
 417       <para revision="278433">The &man.xz.1; utility has been updated
 418         to support multi-threaded compression.</para>
 419
 420       <para revision="280297"><application>OpenSSL</application> has
 421         been updated to version 1.0.1m.</para>
 422
 423       <para revision="280932" contrib="sponsor" sponsor="&ff;">The
 424         <application>elftoolchain</application> utilities have been
 425         updated to version 3179.</para>
 426
 427       <para revision="281316">The &man.xz.1; utility has been updated
 428         to version 5.2.1.</para>
 429
 430       <para revision="281373">The &man.nvi.1; utility has been updated
 431         to version 2.1.3.</para>
 432
 433       <para revision="281396">The &man.acpi.4; subsystem has been
 434         updated to version 20150410.</para>
 435
 436       <para revision="281806">The &man.wpa.supplicant.8; and
 437         &man.hostapd.8; utilities have been updated to version
 438         2.4.</para>
 439
 440       <para revision="281812"><application>bmake</application> has
 441         been updated to version 20150418.</para>
 442
 443       <para revision="282089">The &man.unbound.8; utility has been
 444         updated to version 1.5.3.</para>
 445
 446       <para revision="282434" contrib="sponsor" sponsor="&ff;">The
 447         &man.resolvconf.8; utility has been updated to version
 448         3.7.0.</para>
 449     </sect2>
 450
 451     <sect2 xml:id="userland-installer">
 452       <title>Installation and Configuration Tools</title>
 453
 454       <para revision="271539">The &man.bsdinstall.8; partition editor
 455         and &man.sade.8; utility have been updated to include native
 456         <acronym>ZFS</acronym> support.</para>
 457
 458       <para revision="272274">The &os; installation utility,
 459         &man.bsdinstall.8;, has been updated to set the
 460         <literal>canmount</literal> &man.zfs.8; property to
 461         <literal>off</literal> for the <filename
 462           class="directory">/var</filename> dataset, preventing the
 463         contents of directories within <filename
 464           class="directory">/var</filename> from conflicting when
 465         using multiple boot environments, such as that provided by
 466         <filename role="package">sysutils/beadm</filename>.</para>
 467
 468       <para revision="274394">The &man.bsdconfig.8; utility has been
 469         updated to skip the initial &man.tzsetup.8;
 470         <acronym>UTC</acronym> versus wall-clock time prompt when run
 471         in a virtual machine, determined when the
 472         <literal>kern.vm_guest</literal> &man.sysctl.8; is set to
 473         <literal>1</literal>.</para>
 474
 475       <para revision="275874">The &man.bsdinstall.8; utility has been
 476         updated to use the new &man.dpv.3; library to display progress
 477         when extracting the &os; distributions.</para>
 478     </sect2>
 479
 480     <sect2 xml:id="userland-rc">
 481       <title><filename class="directory">/etc/rc.d</filename>
 482         Scripts</title>
 483
 484       <para revision="270676">The &man.rc.8; subsystem has been
 485         updated to allow configuring services in <filename
 486           class="directory">&dollar;{LOCALBASE}/etc/rc.conf.d/</filename>.
 487         If <literal>LOCALBASE</literal> is unset, it defaults to
 488         <filename class="directory">/usr/local</filename>.</para>
 489
 490       <para revision="275299">The <filename>mrouted</filename>
 491         &man.rc.8; script has been removed from the base system.  An
 492         equivalent script is available from the <filename
 493           role="package">net/mrouted</filename> port.</para>
 494
 495       <para revision="279463" contrib="sponsor"
 496         sponsor="&sandvine;">A new &man.rc.8; script,
 497         <filename>iovctl</filename>, has been added, which allows
 498         automatically starting the &man.iovctl.8; utility at
 499         boot.</para>
 500     </sect2>
 501
 502     <sect2 xml:id="userland-periodic">
 503       <title><filename class="directory">/etc/periodic</filename>
 504         Scripts</title>
 505
 506       <para revision="271321">The daily &man.periodic.8; script
 507         <filename>110.clean-tmps</filename> has been updated to avoid
 508         crossing filesystem mount boundaries when cleaning files in
 509         <filename class="directory">/tmp</filename>.</para>
 510     </sect2>
 511
 512     <sect2 xml:id="userland-libraries">
 513       <title>Runtime Libraries and API</title>
 514
 515       <para revision="268461">The &man.readline.3; library is now
 516         statically linked in software within the base system, and the
 517         shared library is no longer installed, allowing the Ports
 518         Collection to use a modern version of the library.</para>
 519
 520       <para revision="272273">The &man.strptime.3; library has been
 521         updated to add support for <acronym>POSIX</acronym>-2001
 522         features <literal>%U</literal> and
 523         <literal>%W</literal>.</para>
 524
 525       <para revision="272842,272848" contrib="sponsor"
 526         sponsor="&ff;">The &man.dl.iterate.phdr.3; library has been
 527         changed to always return the path name of the
 528         <acronym>ELF</acronym> object in the
 529         <literal>dlpi_name</literal> structure member.</para>
 530
 531       <para revision="273562" contrib="sponsor"
 532         sponsor="&juniper;">The &man.libxo.3; library has been
 533         imported to the base system.</para>
 534
 535       <para revision="273806" contrib="sponsor" sponsor="&chelsio;">A
 536         userland library for Chelsio Terminator 5 based iWARP cards
 537         has been added, allowing userland <acronym>RDMA</acronym>
 538         applications to work over compatible
 539         <acronym>NIC</acronym>s.</para>
 540
 541       <para revision="274987">The &man.gpio.3; library has been added,
 542         providing a wrapper around the &man.gpio.4; kernel
 543         interface.</para>
 544
 545       <para revision="277610">The <literal>futimens()</literal> and
 546         <literal>utimensat()</literal> system calls have been
 547         added.  See &man.utimensat.2; for more information.</para>
 548
 549       <para revision="278934">The &man.elf.3; compile-time dependency
 550         has been removed from <filename>dtri.o</filename>, which
 551         allows adding <application>DTrace</application> probes to
 552         userland applications and libraries without also linking
 553         against &man.elf.3;.</para>
 554
 555       <para revision="279186">The &man.setmode.3; function has been
 556         updated to consistently set <literal>errno</literal> on
 557         failure.</para>
 558
 559       <para revision="279663">The &man.qsort.3; functions have been
 560         updated to be able to handle 32-bit aligned data on 64-bit
 561         platforms, also providing a significant improvement in 32-bit
 562         workloads.</para>
 563
 564       <para revision="281130">Several standard include headers have
 565         been updated to use of <application>gcc</application>
 566         attributes, such as <literal>__result_use_check()</literal>,
 567         <literal>__alloc_size()</literal>, and
 568         <literal>__nonnull()</literal>.</para>
 569
 570       <para revision="281845">Support for file verification in
 571         <acronym>MAC</acronym> has been added.</para>
 572
 573       <para revision="282973" contrib="sponsor" sponsor="&ff;">The
 574         <literal>libgomp</literal> library is now only built when
 575         building <acronym>GCC</acronym> from the base system.  An
 576         up-to-date version is available in the Ports Collection as
 577         <filename
 578           role="package">devel/libiomp5-devel</filename>.</para>
 579
 580       <para revision="282988">The <filename>stdlib.h</filename> and
 581         <filename>malloc.h</filename> headers have been updated to
 582         make use of the <application>gcc</application>
 583         <literal>alloc_align()</literal> attribute.</para>
 584     </sect2>
 585
 586     <sect2 xml:id="userland-abi">
 587       <title>ABI Compatibility</title>
 588
 589       <para revision="271982">The &linux; compatibility version has
 590         been updated to <literal>2.6.18</literal>.  The
 591         <literal>compat.linux.osrelease</literal> &man.sysctl.8; is
 592         evaluated when building the <filename
 593           role="package">emulators/linux-c6</filename> and related
 594         ports.</para>
 595     </sect2>
 596   </sect1>
 597
 598   <sect1 xml:id="kernel">
 599     <title>Kernel</title>
 600
 601     <para>This section covers changes to kernel configurations, system
 602       tuning, and system control parameters that are not otherwise
 603       categorized.</para>
 604
 605     <sect2 xml:id="kernel-bugfix">
 606       <title>Kernel Bug Fixes</title>
 607
 608       <para revision="265876">A kernel bug that inhibited proper
 609         functionality of the <literal>dev.cpu.0.freq</literal>
 610         &man.sysctl.8; on &intel; processors with Turbo
 611         Boost&nbsp;&trade; enabled has been fixed.</para>
 612
 613       <para revision="271697" arch="powerpc">Support for
 614         &man.dtrace.1; stack tracing has been fixed for
 615         &os;/&arch.powerpc;, using the <literal>trapexit()</literal>
 616         and <literal>asttrapexit()</literal> functions instead of
 617         checking within addressed kernel space.</para>
 618
 619       <para revision="272089">A bug in &man.ipfw.4; that could
 620         potentially lead to a kernel panic when using &man.dummynet.4;
 621         at layer 2 has been fixed.</para>
 622
 623       <para revision="280930" contrib="sponsor" sponsor="&mitail;">The
 624         kernel <acronym>RPC</acronym> has been updated to include
 625         several enhancements:</para>
 626
 627       <itemizedlist>
 628         <listitem>
 629           <para>The 45 MiB limit on requests queued for
 630             &man.nfsd.8; threads has been removed.</para>
 631         </listitem>
 632
 633         <listitem>
 634           <para>Avoids unnecessary throttling by not deferring
 635             accounting for completed requests.</para>
 636         </listitem>
 637
 638         <listitem>
 639           <para>Fixes an integer overflow and signedness bugs.</para>
 640         </listitem>
 641       </itemizedlist>
 642
 643       <para revision="281261" arch="powerpc">Support for
 644         &man.dtrace.1; has been added for the
 645         Book-E&nbsp;&trade;.</para>
 646     </sect2>
 647
 648     <sect2 xml:id="kernel-config">
 649       <title>Kernel Configuration</title>
 650
 651       <para revision="266531">The <literal>IMAGACT_BINMISC</literal>
 652         kernel configuration option has been enabled by default,
 653         which enables application execution through emulators, such
 654         as <application>Qemu</application>.</para>
 655
 656       <para revision="268045">The <literal>VT</literal> kernel
 657         configuration file has been removed, and the &man.vt.4;
 658         driver is included in the <literal>GENERIC</literal> kernel.
 659         To enable &man.vt.4;, enter <literal>set kern.vty=vt</literal>
 660         at the &man.loader.8; prompt during boot, or add
 661         <literal>kern.vty=vt</literal> to &man.loader.conf.5; and
 662         reboot the system.</para>
 663
 664       <para revision="277904">The &man.config.8; utility has been
 665         updated to allow using a non-standard <filename
 666           class="directory">src/</filename> tree, specified as an
 667         argument to the <literal>-s</literal> flag.</para>
 668
 669       <para revision="277990" arch="powerpc64">The
 670         &os;/&arch.powerpc64; kernel now builds as
 671         a position-independent executable, allowing the kernel to be
 672         loaded into and run from any physical or virtual
 673         address.</para>
 674
 675       <important>
 676         <para>This change requires an update to &man.loader.8;.
 677           The userland and kernel must be updated before rebooting the
 678           system.</para>
 679       </important>
 680
 681       <para revision="279189" contrib="sponsor" sponsor="&ff;"
 682         arch="powerpc">Kernel support for Vector-Scalar eXtension
 683         (<acronym>VSX</acronym>) found on POWER7 and POWER8 hardware
 684         has been added.</para>
 685
 686       <para revision="279252" contrib="sponsor" sponsor="&ff;"
 687         arch="powerpc">The &man.pmap.9; implementation for 64-bit
 688         &powerpc; processors has been overhaulded to improve
 689         concurrency.</para>
 690     </sect2>
 691
 692     <sect2 xml:id="kernel-sysctl">
 693       <title>System Tuning and Controls</title>
 694
 695       <para revision="275140" contrib="sponsor" sponsor="&ff;">The
 696         &man.hwpmc.4; default and maximum callchain depths have been
 697         increased.  The default has been increased from 16 to 32, and
 698         the maximum increased from 32 to 128.</para>
 699
 700       <para revision="279361">The <literal>kern.osrelease</literal>
 701         and <literal>kern.osreldate</literal> are now configurable
 702         &man.jail.8; parameters.</para>
 703
 704       <para revision="280308,280949" contrib="sponsor"
 705         sponsor="&ix;, &ff;">The &man.devfs.5; device filesystem has
 706         been changed to update timestamps for read/write operations
 707         using seconds precision.  A new &man.sysctl.8;,
 708         <literal>vfs.devfs.dotimes</literal> has been added, which
 709         when set to a non-zero value, enables default precision
 710         timestamps for these operations.</para>
 711
 712       <para revision="282213" contrib="sponsor" sponsor="&ff;">A new
 713         &man.sysctl.8;, <literal>kern.racct.enable</literal>, has been
 714         added, which when set to a non-zero value allows using
 715         &man.rctl.8; with the <literal>GENERIC</literal> kernel.
 716         A new kernel configuration option,
 717         <literal>RACCT_DISABLED</literal> has also been added.</para>
 718
 719       <para revision="282901" contrib="sponsor" sponsor="&ff;">The
 720         <literal>GENERIC</literal> kernel configuration now includes
 721         <literal>RACCT</literal> and <literal>RCTL</literal> by
 722         default.</para>
 723
 724       <note>
 725         <para>To enable <literal>RACCT</literal> and
 726           <literal>RCTL</literal> on a system using the
 727           <literal>GENERIC</literal> kernel configuration, add
 728           <literal>kern.racct.enable=1</literal> to
 729           &man.loader.conf.5;, and reboot the system.</para>
 730       </note>
 731
 732       <para revision="283136" contrib="sponsor"
 733         sponsor="&limelight;">A new &man.sysctl.8;,
 734         <literal>net.inet.tcp.hostcache.purgenow</literal>, has
 735         been added, which when set to <literal>1</literal> during
 736         runtime will flush all
 737         <literal>net.inet.tcp.hostcache</literal> entries.</para>
 738     </sect2>
 739   </sect1>
 740
 741   <sect1 xml:id="drivers">
 742     <title>Devices and Drivers</title>
 743
 744     <para>This section covers changes and additions to devices and
 745       device drivers since &release.prev;.</para>
 746
 747     <sect2 xml:id="drivers-device">
 748       <title>Device Drivers</title>
 749
 750       <para revision="260903">Support for GPS ports has been added to
 751         &man.uhso.4;.</para>
 752
 753       <para revision="265132">The &man.full.4; device has been added,
 754         and the <literal>lindev(4)</literal> device has been removed.
 755         Prior to this change, <literal>lindev(4)</literal> provided
 756         only the <filename>/dev/full</filename> character device,
 757         returning <literal>ENOSPC</literal> on write attempts.  As
 758         this device is not specific to &linux;, a native &os; version
 759         has been added.</para>
 760
 761       <para revision="271705">Hardware context support has been
 762         added to the <literal>drm/i915</literal> driver, adding
 763         support for <application>Mesa</application> 9.2 and
 764         later.</para>
 765
 766       <para revision="273178">The &man.vt.4; driver has been updated,
 767         replacing the bitmapped <literal>kern.vt.spclkeys</literal>
 768         &man.sysctl.8; with individual
 769         <literal>kern.vt.kbd_*</literal> variants.</para>
 770
 771       <para revision="273598">The &man.hpet.4; driver has been updated
 772         to create a
 773         <filename>/dev/hpet<replaceable>N</replaceable></filename>
 774         device, providing access to <acronym>HPET</acronym> from
 775         userspace.</para>
 776
 777       <para revision="280183">The <literal>drm</literal> code has
 778         been updated to match &linux; version 3.8.13.</para>
 779
 780       <para revision="282783" arch="powerpc">Support for the Freescale
 781         <acronym>PCI</acronym> Root Complex device has been
 782         added.</para>
 783     </sect2>
 784
 785     <sect2 xml:id="drivers-storage">
 786       <title>Storage Drivers</title>
 787
 788       <para revision="265236" contrib="sponsor"
 789         sponsor="&lsi;, &spectralogic;" sponsorurl="">The &man.mpr.4;
 790         device has been added, providing support for LSI Fusion-MPT
 791         3 12Gb SCSI/SATA controllers.</para>
 792
 793       <para revision="265555" contrib="sponsor"
 794           sponsor="&lsi;">The &man.mrsas.4; driver has been added,
 795         providing support for LSI MegaRAID SAS controllers.  The
 796         &man.mfi.4; driver will attach to the controller, by default.
 797         To enable &man.mrsas.4; add
 798         <literal>hw.mfi.mrsas_enable=1</literal> to
 799         <filename>/boot/loader.conf</filename>, which turns off
 800         &man.mfi.4; device probing.</para>
 801
 802       <note>
 803         <para>At this time, the &man.mfiutil.8; utility and the &os;
 804           version of <application>MegaCLI</application> and
 805           <application>StorCli</application> do not work with
 806           &man.mrsas.4;.</para>
 807       </note>
 808
 809       <para revision="275461" contrib="sponsor" sponsor="&ix;">The
 810         &man.ctl.4; subsystem has been updated, increasing the ports
 811         limit from <literal>128</literal> to <literal>256</literal>,
 812         and <acronym>LUN</acronym> limit from <literal>256</literal>
 813         to <literal>1024</literal>.</para>
 814
 815       <para revision="276526">The <literal>asr(4)</literal> driver has
 816         been removed, and is no longer supported.</para>
 817
 818       <para revision="281387">The &man.hptnr.4; driver has been
 819         updated to version 1.1.1.</para>
 820     </sect2>
 821
 822     <sect2 xml:id="drivers-network">
 823       <title>Network Drivers</title>
 824
 825       <para revision="258830">Support for Broadcom chipsets BCM57764,
 826         BCM57767, BCM57782, BCM57786 and BCM57787 has been added to
 827         &man.bge.4;.</para>
 828
 829       <para revision="260448">Support for the &intel; Centrino&trade;
 830         Wireless-N 135 chipset has been added.</para>
 831
 832       <para revision="260552">Firmware for &intel; Centrino&trade;
 833         Wireless-N 105 devices has been added to the base
 834         system.</para>
 835
 836       <para revision="261975">The deprecated nve(4) driver has been
 837         removed.  Users of NVIDIA nForce MCP network adapters are
 838         advised to use the &man.nfe.4; driver instead, which has been
 839         the default driver for this hardware since
 840         &os;&nbsp;7.0.</para>
 841
 842       <para revision="264601" contrib="sponsor"
 843         sponsor="&darpa_afrl;">The <literal>if_nf10bmac(4)</literal>
 844         device has been added, providing support for NetFPGA-10G
 845         Embedded CPU Ethernet Core.</para>
 846
 847       <note>
 848         <para>The <literal>if_nf10bmac(4)</literal> driver operates on
 849           the FPGA, and is not suited for the PCI host
 850           interface.</para>
 851       </note>
 852
 853       <para revision="265348" contrib="sponsor"
 854         sponsor="&netgate;">The &man.ath.hal.4; driver has been
 855         updated to support the Atheros AR1111 chipset.</para>
 856
 857       <para revision="266770">Support for the &intel; Centrino&trade;
 858         Wireless-N 105 chipset has been added.</para>
 859
 860       <para revision="266757" contrib="sponsor"
 861         sponsor="&chelsio;">Support for the &man.cxgbe.4; Terminator
 862         5 (T5) 10G/40G cards has been added to &man.netmap.4;.</para>
 863
 864       <para revision="272730">The &man.alc.4; driver has been updated
 865         to support AR816x and AR817x ethernet controllers.</para>
 866
 867       <para revision="273331">The &man.vxlan.4; driver has been added,
 868         which creates a virtual Layer 2 (Ethernet) network overlaid in
 869         a Layer 3 (IP/UDP) network.  The &man.vxlan.4; driver is
 870         analogous to &man.vlan.4;, but is designed to be better suited
 871         for large, multiple-tenant datacenter environments.</para>
 872
 873       <para revision="274246" contrib="sponsor" sponsor="&yandex;">The
 874         &man.gre.4; driver has been significantly overhauled, and has
 875         been split into two separate modules, &man.gre.4; and
 876         &man.me.4;.</para>
 877
 878       <para revision="283766" contrib="sponsor"
 879         sponsor="&limelight;">The &man.em.4; driver has been updated
 880         with improved transmission queue hang detection.</para>
 881     </sect2>
 882   </sect1>
 883
 884   <sect1 xml:id="hardware">
 885     <title>Hardware Support</title>
 886
 887     <para>This section covers general hardware support for physical
 888       machines, hypervisors, and virtualization environments, as well
 889       as hardware changes and updates that do not otherwise fit in
 890       other sections of this document.</para>
 891
 892     <sect2 xml:id="hardware-support">
 893       <title>Hardware Support</title>
 894
 895       <para revision="268303">The &man.asmc.4; driver has been
 896         updated to support the &apple;&nbsp;MacMini 3,1.</para>
 897
 898       <para revision="268351">Support for &os;/ia64 has been dropped
 899         as of &os;&nbsp;11.</para>
 900
 901       <para revision="274386">An issue that could cause a system to
 902         hang when entering <acronym>ACPI</acronym>
 903         <literal>S3</literal> state (suspend to
 904         <acronym>RAM</acronym>) has been corrected in the &man.acpi.4;
 905         and &man.pci.4; drivers.</para>
 906
 907       <para revision="274733" arch="powerpc">The power management unit
 908         subsystem has been updated to support power button events on
 909         certain &arch.powerpc; hardware, such as aluminum
 910         PowerBook&nbsp;&reg;.</para>
 911
 912       <para revision="275171,275190" arch="powerpc">The &man.hwpmc.4;
 913         driver has been updated to correct performance counter
 914         sampling on G4 (MPC74xxx) and G5 class processors.</para>
 915
 916       <para revision="281713" arch="powerpc">The &man.hwpmc.4;
 917         driver has been updated to support the Freescale e500
 918         core.</para>
 919
 920       <para revision="275732" contrib="sponsor"
 921         sponsor="&ff;,&netgate;">The
 922         <application>OpenCrypto</application> framework has been
 923         updated to include <literal>AES-ICM</literal> and
 924         <literal>AES-GCM</literal> modes, both of which have also been
 925         added to the &man.aesni.4; driver.</para>
 926
 927       <para revision="283766">The &man.ig4.4; driver has been added,
 928         providing support for the fourth generation &intel;
 929         <acronym>I2C</acronym> SMBus.</para>
 930     </sect2>
 931
 932     <sect2 xml:id="hardware-virtualization">
 933       <title>Virtualization Support</title>
 934
 935       <para revision="260410">Support for the <quote>Virtual Interrupt
 936           Delivery</quote> feature of &intel;&nbsp;VT-x is enabled if
 937         supported by the CPU.  This feature can be disabled by running
 938         <literal>sysctl hw.vmm.vmx.use_apic_vid=0</literal>.
 939         Additionally, to persist this setting across reboots, add
 940         <literal>hw.vmm.vmx.use_apic_vid=0</literal> to
 941         <filename>/etc/sysctl.conf</filename>.</para>
 942
 943       <para revision="260532">Support for <quote>Posted Interrupt
 944           Processing</quote> is enabled if supported by the CPU.  This
 945         feature can be disabled by running <literal>sysctl
 946           hw.vmm.vmx.use_apic_pir=0</literal>.  Additionally, to
 947         persist this setting across reboots, add
 948         <literal>hw.vmm.vmx.use_apic_pir=0</literal> to
 949         <filename>/etc/sysctl.conf</filename>.</para>
 950
 951       <para revision="260582">Unmapped IO support has been added to
 952         &man.virtio_blk.4;.</para>
 953
 954       <para revision="260583">Unmapped IO support has been added to
 955         &man.virtio_scsi.4;.</para>
 956
 957       <para revision="260847">The &man.virtio_random.4; driver has
 958         been added to harvest entropy from the host system.</para>
 959
 960       <para revision="261504">&os;/&arch.i386; guests can be run under
 961         bhyve.</para>
 962
 963       <para revision="267536" contrib="sponsor"
 964         sponsor="&citrix.rd;">Support for running a &os;/&arch.amd64;
 965         <application>Xen</application> guest instance as
 966         <acronym>PVH</acronym> guest has been added.
 967         <acronym>PVH</acronym> mode, short for <quote>Para-Virtualized
 968           Hardware</quote>, uses para-virtualized drivers for boot and
 969         I/O, and uses hardware virtualization extensions for all other
 970         tasks, without the need for emulation.</para>
 971
 972       <para revision="273515">The &man.virtio.console.4; driver has
 973         been added, which provides an interface to VirtIO console
 974         devices through a &man.tty.4; device.</para>
 975
 976       <para revision="279957">The &man.bhyve.8; hypervisor has been
 977         updated to support <literal>DSM TRIM</literal> commands for
 978         virtual <acronym>AHCI</acronym> disks.</para>
 979
 980       <para revision="281439" arch="arm">Support for the
 981         <application>QEMU</application> <literal>virt</literal> system
 982         has been added.</para>
 983
 984       <para revision="282212" contrib="sponsor" sponsor="&msostc;">The
 985         HyperV&trade; drivers have been updated with several
 986         enhancements:</para>
 987
 988       <itemizedlist>
 989         <listitem>
 990           <para>The &man.hv.vmbus.4; driver now has multi-channel
 991             support.</para>
 992         </listitem>
 993
 994         <listitem>
 995           <para>The &man.hv.storvsc.4; driver now has scatter/gather
 996             support, in addition to performance improvements.</para>
 997         </listitem>
 998
 999         <listitem>
1000           <para>The &man.hv.kvp.4; driver has received several bug
1001             fixes.</para>
1002         </listitem>
1003       </itemizedlist>
1004
1005       <para revision="282274">Support for &man.xen.4; para-virtualized
1006         <literal>domU</literal> kernels has been removed.</para>
1007     </sect2>
1008
1009     <sect2 xml:id="hardware-arm">
1010       <title>ARM Support</title>
1011
1012       <para revision="260921">The &man.nand.4; device is enabled for
1013         ARM devices by default.</para>
1014
1015       <para revision="273264" arch="armv6">An issue that could cause
1016         instability when detecting <acronym>SD</acronym> cards on the
1017         Raspberry Pi <acronym>SOC</acronym> has been fixed.</para>
1018
1019       <para revision="275963">The <literal>bcm2835_cpufreq</literal>
1020         driver has been added, which supports <acronym>CPU</acronym>
1021         frequency and voltage control on the Raspberry Pi
1022         <acronym>SOC</acronym>.</para>
1023
1024       <para revision="280259" contrib="sponsor" sponsor="&ff;">Initial
1025         support for the ARM AArch64 architecture has been
1026         added.</para>
1027
1028       <para revision="282779" arch="arm">Kernel support for Thumb-2
1029         has been added.</para>
1030
1031       <para revision="282827">Support for the hardware power button
1032         on the BeagleBone Black system has been added.</para>
1033     </sect2>
1034   </sect1>
1035
1036   <sect1 xml:id="storage">
1037     <title>Storage</title>
1038
1039     <para>This section covers changes and additions to file systems
1040       and other storage subsystems, both local and networked.</para>
1041
1042     <sect2 xml:id="storage-general">
1043       <title>General Storage</title>
1044
1045       <para revision="278037" contrib="sponsor" sponsor="&ix;">The
1046         &man.ctl.4; <acronym>LUN</acronym> mapping has been rewritten,
1047         replacing <acronym>iSCSI</acronym>-specific mapping mechanisms
1048         with a new mechanism that works for any port.</para>
1049
1050       <para revision="278354" contrib="sponsor" sponsor="&ix;">The
1051         &man.ctld.8; utility has been updated to allow controlling
1052         non-<acronym>iSCSI</acronym> &man.ctl.4; ports.</para>
1053     </sect2>
1054
1055     <sect2 xml:id="storage-net">
1056       <title>Networked Storage</title>
1057
1058       <para revision="270096" contrib="sponsor" sponsor="&ff;">The new
1059         filesystem automount facility, &man.autofs.5;, has been added.
1060         The new &man.autofs.5; facility is similar to that found in
1061         other &unix;-like operating systems, such as OS&nbsp;X&trade;
1062         and Solaris&trade;.  The &man.autofs.5; facility uses
1063         a &sun;-compatible &man.auto.master.5; configuration file, and
1064         is administered with the &man.automount.8; userland utility,
1065         and the &man.automountd.8; and &man.autounmountd.8;
1066         daemons.</para>
1067     </sect2>
1068
1069     <sect2 xml:id="storage-zfs">
1070       <title>ZFS</title>
1071
1072       <para revision="275748">The <literal>arc_meta_limit</literal>
1073         statistics are now visible through the
1074         <literal>kstat</literal> &man.sysctl.8;.  As a result of this
1075         change, the <literal>vfs.zfs.arc_meta_used</literal>
1076         &man.sysctl.8; has been removed, and replaced with the
1077         <literal>kstat.zfs.misc.arcstats.arc_meta_used</literal>
1078         &man.sysctl.8;.</para>
1079     </sect2>
1080
1081     <sect2 xml:id="storage-geom">
1082       <title>&man.geom.4;</title>
1083
1084       <para revision="267359">Support for the
1085         <literal>disklabel64</literal> partitioning scheme has been
1086         added to &man.gpart.8;.</para>
1087     </sect2>
1088   </sect1>
1089
1090   <sect1 xml:id="boot">
1091     <title>Boot Loader Changes</title>
1092
1093     <para>This section covers the boot loader, boot menu, and other
1094       boot-related changes.</para>
1095
1096     <sect2 xml:id="boot-loader">
1097       <title>Boot Loader Changes</title>
1098
1099       <para revision="274085">The &man.vt.4; driver has been made the
1100         default system console driver.  The &man.syscons.4; driver is
1101         still available, and can be enabled by adding
1102         <literal>kern.vty=sc</literal> in &man.loader.conf.5;.
1103         Alternatively, &man.syscons.4; can be enabled at boot time by
1104         entering <literal>set kern.vty=sc</literal> at the
1105         &man.loader.8; prompt.</para>
1106
1107       <para revision="281616">The boot loader has been updated to
1108         support entering the <acronym>GELI</acronym> passphrase before
1109         loading the kernel.  To enable this behavior, add
1110         <literal>geom_eli_passphrase_prompt="YES"</literal> to
1111         &man.loader.conf.5;.</para>
1112     </sect2>
1113
1114     <sect2 xml:id="boot-menu">
1115       <title>Boot Menu Changes</title>
1116
1117       <para>&nbsp;</para>
1118     </sect2>
1119   </sect1>
1120
1121   <sect1 xml:id="network">
1122     <title>Networking</title>
1123
1124     <para>This section describes changes that affect networking in
1125       &os;.</para>
1126
1127     <sect2 xml:id="network-protocols">
1128       <title>Network Procols</title>
1129
1130       <para revision="263140">Support for the IPX network transport
1131         protocol has been removed, and will not be supported in
1132         &os;&nbsp;11 and later releases.</para>
1133
1134       <para revision="272720" contrib="sponsor"
1135         sponsor="&limelight;">Support for <acronym>PLPMTUD</acronym>
1136         blackhole detection (<acronym>RFC</acronym> 4821) has been
1137         added to the &man.tcp.4; stack, disabled by default.  New
1138         control tunables have been added:</para>
1139
1140       <informaltable frame="none" pgwide="0">
1141         <tgroup cols="2">
1142           <colspec colwidth="1*"/>
1143           <colspec colwidth="1*"/>
1144           <thead>
1145             <row>
1146               <entry>Tunable</entry>
1147               <entry>Description</entry>
1148             </row>
1149           </thead>
1150
1151           <tbody>
1152             <row>
1153               <entry><literal>net.inet.tcp.pmtud_blackhole_detection</literal></entry>
1154               <entry>Enables or disables <acronym>PLPMTUD</acronym>
1155                 blackhole detection</entry>
1156             </row>
1157
1158             <row>
1159               <entry><literal>net.inet.tcp.pmtud_blackhole_mss</literal></entry>
1160               <entry><acronym>MSS</acronym> to try for IPv4</entry>
1161             </row>
1162
1163             <row>
1164               <entry><literal>net.inet.tcp.v6pmtud_blackhole_mss</literal></entry>
1165               <entry><acronym>MSS to try for IPv6</acronym></entry>
1166             </row>
1167           </tbody>
1168         </tgroup>
1169       </informaltable>
1170
1171       <para>New monitoring &man.sysctl.8;s haven been added:</para>
1172
1173       <informaltable frame="none" pgwide="0">
1174         <tgroup cols="2">
1175           <colspec colwidth="1*"/>
1176           <colspec colwidth="1*"/>
1177           <thead>
1178             <row>
1179               <entry>Tunable</entry>
1180               <entry>Description</entry>
1181             </row>
1182           </thead>
1183
1184           <tbody>
1185             <row>
1186               <entry><literal>net.inet.tcp.pmtud_blackhole_activated</literal></entry>
1187               <entry>Number of times the code was activated to attempt
1188                 downshifting the <acronym>MSS</acronym></entry>
1189             </row>
1190
1191             <row>
1192               <entry><literal>net.inet.tcp.pmtud_blackhole_min_activated</literal></entry>
1193               <entry>Number of times the blackhole
1194                 <acronym>MSS</acronym> was used in an attempt to
1195                 downshift</entry>
1196             </row>
1197
1198             <row>
1199               <entry><literal>net.inet.tcp.pmtud_blackhole_failed</literal></entry>
1200               <entry>Number of times that the blackhole failed to
1201                 connect after downshifting the
1202                 <acronym>MSS</acronym></entry>
1203             </row>
1204           </tbody>
1205         </tgroup>
1206       </informaltable>
1207
1208       <para revision="280971" contrib="sponsor"
1209         sponsor="&netflix;, &nginx;">Support for <acronym>IP</acronym>
1210         identification for atomic datagrams (<acronym>RFC</acronym>
1211         6864) has been added.  Support for this feature can be toggled
1212         with the <literal>net.inet.ip.rfc6864</literal>
1213         &man.sysctl.8;, which is enabled by default.</para>
1214     </sect2>
1215   </sect1>
1216
1217   <sect1 xml:id="ports">
1218     <title>Ports Collection and Package Infrastructure</title>
1219
1220     <para>This section covers changes to the &os;&nbsp;Ports
1221       Collection, package infrastructure, and package maintenance and
1222       installation tools.</para>
1223
1224     <sect2 xml:id="ports-infrastructure">
1225       <title>Infrastructure Changes</title>
1226
1227       <para>&nbsp;</para>
1228     </sect2>
1229
1230     <sect2 xml:id="ports-packages ">
1231       <title>Packaging Changes</title>
1232
1233       <para>&nbsp;</para>
1234     </sect2>
1235   </sect1>
1236
1237   <sect1 xml:id="doc">
1238     <title>Documentation</title>
1239
1240     <para>This section covers changes to the &os;&nbsp;Documentation
1241       Project sources and toolchain.</para>
1242
1243     <sect2 xml:id="doc-sources">
1244       <title>Documentation Source Changes</title>
1245
1246       <para>&nbsp;</para>
1247     </sect2>
1248
1249     <sect2 xml:id="doc-toolchain">
1250       <title>Documentation Toolchain Changes</title>
1251
1252       <para>&nbsp;</para>
1253     </sect2>
1254   </sect1>
1255
1256   <sect1 xml:id="releng">
1257     <title>Release Engineering and Integration</title>
1258
1259     <para>This section convers changes that are specific to the
1260       &os;&nbsp;Release Engineering processes.</para>
1261
1262     <sect2 xml:id="releng-changes">
1263       <title>Integration Changes</title>
1264
1265       <para revision="277458" contrib="sponsor" sponsor="&ff;">The
1266         Release Engineering build tools have been updated to include
1267         support for producing virtual machine disk images for various
1268         cloud hosting providers.</para>
1269
1270       <para revision="278926">The Release Engineering build tools have
1271         been updated to use multi-threaded &man.xz.1;.  By default,
1272         the number of &man.xz.1; threads is set to the number of cores
1273         available.</para>
1274
1275       <para revision="281802" contrib="sponsor" sponsor="&ff;">The
1276         Release Engineering build tools have been updated to include
1277         support for building &os;/&arch.arm64; virtual machine and
1278         memory stick installation images.</para>
1279     </sect2>
1280   </sect1>
1281 </article>