1 2GNU General Public License 3-------------------------- 4 5Most files in this repository are licensed under the terms of the GNU 6General Public License (GPL), a copy of which is attached at the end 7of this notice. Note that the only valid version of the GPL as far as 8the files in this repository are concerned is _this_ particular 9version of the license (i.e., *only* v2, not v2.2 or v3.x or 10whatever), unless explicitly otherwise stated. 11 12Some code fragments in the hypervisor and associated subsystems 13include other license stanzas: the most common ones are listed in 14the *License Exceptions* section of this file. 15 16When these code sections are compiled as part of a 17GPLv2-licensed program, such as Xen, the result is licensed under 18GPLv2. See the FSF's definition of GPL compatibility: 19 http://www.gnu.org/licenses/gpl-faq.html#WhatDoesCompatMean 20And how this applies to a range of open source licenses: 21 http://www.gnu.org/licenses/license-list.html 22 23A number of files will also specify GPL exceptions, such as 24 - Autoconf exception 25 - Bison exception 26 - GCC exception 27 28In addition the xen directory also contains a XEN NOTICE clarifying 29what constitutes a derived work, which applies to the xen directory 30and its subdirectories (see xen/COPYING). 31 32Licensing Exceptions 33-------------------- 34 35For the convenience of users and those who are porting OSes to run as 36Xen guests, certain files in this repository are not subject to the 37GPL when distributed separately or included in software packages 38outside this repository. 39 40Instead we specify more relaxed licenses, depending on need, such as 41 - BSD style license (BSD Original, BSD Modified, Intel BSD) 42 - MIT license 43 - LGPL 2.1 44 45Affected files include the Xen interface headers (xen/include/public), 46various drivers, support functions and header files within Xen-aware 47Linux source trees. In all such cases, license terms are stated at the 48top of the file or in a COPYING file in the same directory. 49 50In some cases, compatible 3rd party code has been imported into the 51Xen tree, retaining the original license, such as 52 - AES-128 3.0 53 - FSF Unlimited License 54 - Laurikari License 55 - Public Domain 56 - ZLIB License 57 - ZPL 2.0 58 59Significant code imports are highlighted in a README.source file 60in the directory into which the file or code snippet was imported. 61 62Note that *any* file that is modified and then distributed within a 63Linux kernel is still subject to the GNU GPL. 64 65Contributions 66------------- 67 68Contributions are governed by the license that applies to the relevant 69specific file or by the license specified in the COPYING file, that 70governs the license of its containing directory and its subdirectories. 71 72For more information, see the CONTRIBUTING file. 73 74===================================================================== 75 76 GNU GENERAL PUBLIC LICENSE 77 Version 2, June 1991 78 79 Copyright (C) 1989, 1991 Free Software Foundation, Inc. 80 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 81 Everyone is permitted to copy and distribute verbatim copies 82 of this license document, but changing it is not allowed. 83 84 Preamble 85 86 The licenses for most software are designed to take away your 87freedom to share and change it. By contrast, the GNU General Public 88License is intended to guarantee your freedom to share and change free 89software--to make sure the software is free for all its users. This 90General Public License applies to most of the Free Software 91Foundation's software and to any other program whose authors commit to 92using it. (Some other Free Software Foundation software is covered by 93the GNU Library General Public License instead.) You can apply it to 94your programs, too. 95 96 When we speak of free software, we are referring to freedom, not 97price. Our General Public Licenses are designed to make sure that you 98have the freedom to distribute copies of free software (and charge for 99this service if you wish), that you receive source code or can get it 100if you want it, that you can change the software or use pieces of it 101in new free programs; and that you know you can do these things. 102 103 To protect your rights, we need to make restrictions that forbid 104anyone to deny you these rights or to ask you to surrender the rights. 105These restrictions translate to certain responsibilities for you if you 106distribute copies of the software, or if you modify it. 107 108 For example, if you distribute copies of such a program, whether 109gratis or for a fee, you must give the recipients all the rights that 110you have. You must make sure that they, too, receive or can get the 111source code. And you must show them these terms so they know their 112rights. 113 114 We protect your rights with two steps: (1) copyright the software, and 115(2) offer you this license which gives you legal permission to copy, 116distribute and/or modify the software. 117 118 Also, for each author's protection and ours, we want to make certain 119that everyone understands that there is no warranty for this free 120software. If the software is modified by someone else and passed on, we 121want its recipients to know that what they have is not the original, so 122that any problems introduced by others will not reflect on the original 123authors' reputations. 124 125 Finally, any free program is threatened constantly by software 126patents. We wish to avoid the danger that redistributors of a free 127program will individually obtain patent licenses, in effect making the 128program proprietary. To prevent this, we have made it clear that any 129patent must be licensed for everyone's free use or not licensed at all. 130 131 The precise terms and conditions for copying, distribution and 132modification follow. 133 134 GNU GENERAL PUBLIC LICENSE 135 TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION 136 137 0. This License applies to any program or other work which contains 138a notice placed by the copyright holder saying it may be distributed 139under the terms of this General Public License. The "Program", below, 140refers to any such program or work, and a "work based on the Program" 141means either the Program or any derivative work under copyright law: 142that is to say, a work containing the Program or a portion of it, 143either verbatim or with modifications and/or translated into another 144language. (Hereinafter, translation is included without limitation in 145the term "modification".) Each licensee is addressed as "you". 146 147Activities other than copying, distribution and modification are not 148covered by this License; they are outside its scope. The act of 149running the Program is not restricted, and the output from the Program 150is covered only if its contents constitute a work based on the 151Program (independent of having been made by running the Program). 152Whether that is true depends on what the Program does. 153 154 1. You may copy and distribute verbatim copies of the Program's 155source code as you receive it, in any medium, provided that you 156conspicuously and appropriately publish on each copy an appropriate 157copyright notice and disclaimer of warranty; keep intact all the 158notices that refer to this License and to the absence of any warranty; 159and give any other recipients of the Program a copy of this License 160along with the Program. 161 162You may charge a fee for the physical act of transferring a copy, and 163you may at your option offer warranty protection in exchange for a fee. 164 165 2. You may modify your copy or copies of the Program or any portion 166of it, thus forming a work based on the Program, and copy and 167distribute such modifications or work under the terms of Section 1 168above, provided that you also meet all of these conditions: 169 170 a) You must cause the modified files to carry prominent notices 171 stating that you changed the files and the date of any change. 172 173 b) You must cause any work that you distribute or publish, that in 174 whole or in part contains or is derived from the Program or any 175 part thereof, to be licensed as a whole at no charge to all third 176 parties under the terms of this License. 177 178 c) If the modified program normally reads commands interactively 179 when run, you must cause it, when started running for such 180 interactive use in the most ordinary way, to print or display an 181 announcement including an appropriate copyright notice and a 182 notice that there is no warranty (or else, saying that you provide 183 a warranty) and that users may redistribute the program under 184 these conditions, and telling the user how to view a copy of this 185 License. (Exception: if the Program itself is interactive but 186 does not normally print such an announcement, your work based on 187 the Program is not required to print an announcement.) 188 189These requirements apply to the modified work as a whole. If 190identifiable sections of that work are not derived from the Program, 191and can be reasonably considered independent and separate works in 192themselves, then this License, and its terms, do not apply to those 193sections when you distribute them as separate works. But when you 194distribute the same sections as part of a whole which is a work based 195on the Program, the distribution of the whole must be on the terms of 196this License, whose permissions for other licensees extend to the 197entire whole, and thus to each and every part regardless of who wrote it. 198 199Thus, it is not the intent of this section to claim rights or contest 200your rights to work written entirely by you; rather, the intent is to 201exercise the right to control the distribution of derivative or 202collective works based on the Program. 203 204In addition, mere aggregation of another work not based on the Program 205with the Program (or with a work based on the Program) on a volume of 206a storage or distribution medium does not bring the other work under 207the scope of this License. 208 209 3. You may copy and distribute the Program (or a work based on it, 210under Section 2) in object code or executable form under the terms of 211Sections 1 and 2 above provided that you also do one of the following: 212 213 a) Accompany it with the complete corresponding machine-readable 214 source code, which must be distributed under the terms of Sections 215 1 and 2 above on a medium customarily used for software interchange; or, 216 217 b) Accompany it with a written offer, valid for at least three 218 years, to give any third party, for a charge no more than your 219 cost of physically performing source distribution, a complete 220 machine-readable copy of the corresponding source code, to be 221 distributed under the terms of Sections 1 and 2 above on a medium 222 customarily used for software interchange; or, 223 224 c) Accompany it with the information you received as to the offer 225 to distribute corresponding source code. (This alternative is 226 allowed only for noncommercial distribution and only if you 227 received the program in object code or executable form with such 228 an offer, in accord with Subsection b above.) 229 230The source code for a work means the preferred form of the work for 231making modifications to it. For an executable work, complete source 232code means all the source code for all modules it contains, plus any 233associated interface definition files, plus the scripts used to 234control compilation and installation of the executable. However, as a 235special exception, the source code distributed need not include 236anything that is normally distributed (in either source or binary 237form) with the major components (compiler, kernel, and so on) of the 238operating system on which the executable runs, unless that component 239itself accompanies the executable. 240 241If distribution of executable or object code is made by offering 242access to copy from a designated place, then offering equivalent 243access to copy the source code from the same place counts as 244distribution of the source code, even though third parties are not 245compelled to copy the source along with the object code. 246 247 4. You may not copy, modify, sublicense, or distribute the Program 248except as expressly provided under this License. Any attempt 249otherwise to copy, modify, sublicense or distribute the Program is 250void, and will automatically terminate your rights under this License. 251However, parties who have received copies, or rights, from you under 252this License will not have their licenses terminated so long as such 253parties remain in full compliance. 254 255 5. You are not required to accept this License, since you have not 256signed it. However, nothing else grants you permission to modify or 257distribute the Program or its derivative works. These actions are 258prohibited by law if you do not accept this License. Therefore, by 259modifying or distributing the Program (or any work based on the 260Program), you indicate your acceptance of this License to do so, and 261all its terms and conditions for copying, distributing or modifying 262the Program or works based on it. 263 264 6. Each time you redistribute the Program (or any work based on the 265Program), the recipient automatically receives a license from the 266original licensor to copy, distribute or modify the Program subject to 267these terms and conditions. You may not impose any further 268restrictions on the recipients' exercise of the rights granted herein. 269You are not responsible for enforcing compliance by third parties to 270this License. 271 272 7. If, as a consequence of a court judgment or allegation of patent 273infringement or for any other reason (not limited to patent issues), 274conditions are imposed on you (whether by court order, agreement or 275otherwise) that contradict the conditions of this License, they do not 276excuse you from the conditions of this License. If you cannot 277distribute so as to satisfy simultaneously your obligations under this 278License and any other pertinent obligations, then as a consequence you 279may not distribute the Program at all. For example, if a patent 280license would not permit royalty-free redistribution of the Program by 281all those who receive copies directly or indirectly through you, then 282the only way you could satisfy both it and this License would be to 283refrain entirely from distribution of the Program. 284 285If any portion of this section is held invalid or unenforceable under 286any particular circumstance, the balance of the section is intended to 287apply and the section as a whole is intended to apply in other 288circumstances. 289 290It is not the purpose of this section to induce you to infringe any 291patents or other property right claims or to contest validity of any 292such claims; this section has the sole purpose of protecting the 293integrity of the free software distribution system, which is 294implemented by public license practices. Many people have made 295generous contributions to the wide range of software distributed 296through that system in reliance on consistent application of that 297system; it is up to the author/donor to decide if he or she is willing 298to distribute software through any other system and a licensee cannot 299impose that choice. 300 301This section is intended to make thoroughly clear what is believed to 302be a consequence of the rest of this License. 303 304 8. If the distribution and/or use of the Program is restricted in 305certain countries either by patents or by copyrighted interfaces, the 306original copyright holder who places the Program under this License 307may add an explicit geographical distribution limitation excluding 308those countries, so that distribution is permitted only in or among 309countries not thus excluded. In such case, this License incorporates 310the limitation as if written in the body of this License. 311 312 9. The Free Software Foundation may publish revised and/or new versions 313of the General Public License from time to time. Such new versions will 314be similar in spirit to the present version, but may differ in detail to 315address new problems or concerns. 316 317Each version is given a distinguishing version number. If the Program 318specifies a version number of this License which applies to it and "any 319later version", you have the option of following the terms and conditions 320either of that version or of any later version published by the Free 321Software Foundation. If the Program does not specify a version number of 322this License, you may choose any version ever published by the Free Software 323Foundation. 324 325 10. If you wish to incorporate parts of the Program into other free 326programs whose distribution conditions are different, write to the author 327to ask for permission. For software which is copyrighted by the Free 328Software Foundation, write to the Free Software Foundation; we sometimes 329make exceptions for this. Our decision will be guided by the two goals 330of preserving the free status of all derivatives of our free software and 331of promoting the sharing and reuse of software generally. 332 333 NO WARRANTY 334 335 11. BECAUSE THE PROGRAM IS LICENSED FREE OF CHARGE, THERE IS NO WARRANTY 336FOR THE PROGRAM, TO THE EXTENT PERMITTED BY APPLICABLE LAW. EXCEPT WHEN 337OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES 338PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED 339OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 340MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE ENTIRE RISK AS 341TO THE QUALITY AND PERFORMANCE OF THE PROGRAM IS WITH YOU. SHOULD THE 342PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING, 343REPAIR OR CORRECTION. 344 345 12. IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING 346WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY AND/OR 347REDISTRIBUTE THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, 348INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING 349OUT OF THE USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED 350TO LOSS OF DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY 351YOU OR THIRD PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER 352PROGRAMS), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE 353POSSIBILITY OF SUCH DAMAGES. 354 355 END OF TERMS AND CONDITIONS 356 357 How to Apply These Terms to Your New Programs 358 359 If you develop a new program, and you want it to be of the greatest 360possible use to the public, the best way to achieve this is to make it 361free software which everyone can redistribute and change under these terms. 362 363 To do so, attach the following notices to the program. It is safest 364to attach them to the start of each source file to most effectively 365convey the exclusion of warranty; and each file should have at least 366the "copyright" line and a pointer to where the full notice is found. 367 368 <one line to give the program's name and a brief idea of what it does.> 369 Copyright (C) <year> <name of author> 370 371 This program is free software; you can redistribute it and/or modify 372 it under the terms of the GNU General Public License as published by 373 the Free Software Foundation; either version 2 of the License, or 374 (at your option) any later version. 375 376 This program is distributed in the hope that it will be useful, 377 but WITHOUT ANY WARRANTY; without even the implied warranty of 378 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 379 GNU General Public License for more details. 380 381 You should have received a copy of the GNU General Public License 382 along with this program; If not, see <http://www.gnu.org/licenses/>. 383 384 385Also add information on how to contact you by electronic and paper mail. 386 387If the program is interactive, make it output a short notice like this 388when it starts in an interactive mode: 389 390 Gnomovision version 69, Copyright (C) year name of author 391 Gnomovision comes with ABSOLUTELY NO WARRANTY; for details type `show w'. 392 This is free software, and you are welcome to redistribute it 393 under certain conditions; type `show c' for details. 394 395The hypothetical commands `show w' and `show c' should show the appropriate 396parts of the General Public License. Of course, the commands you use may 397be called something other than `show w' and `show c'; they could even be 398mouse-clicks or menu items--whatever suits your program. 399 400You should also get your employer (if you work as a programmer) or your 401school, if any, to sign a "copyright disclaimer" for the program, if 402necessary. Here is a sample; alter the names: 403 404 Yoyodyne, Inc., hereby disclaims all copyright interest in the program 405 `Gnomovision' (which makes passes at compilers) written by James Hacker. 406 407 <signature of Ty Coon>, 1 April 1989 408 Ty Coon, President of Vice 409 410This General Public License does not permit incorporating your program into 411proprietary programs. If your program is a subroutine library, you may 412consider it more useful to permit linking proprietary applications with the 413library. If this is what you want to do, use the GNU Library General 414Public License instead of this License. 415