182537b71Srtmxv6 is a re-implementation of Dennis Ritchie's and Ken Thompson's Unix 282537b71SrtmVersion 6 (v6). xv6 loosely follows the structure and style of v6, 382537b71Srtmbut is implemented for a modern x86-based multiprocessor using ANSI C. 4b52151e0Skaashoek 5bc54fa39SrtmACKNOWLEDGMENTS 62e898063Skaashoek 7f0400600Srscxv6 is inspired by John Lions's Commentary on UNIX 6th Edition (Peer 882537b71Srtmto Peer Communications; ISBN: 1-57398-013-7; 1st edition (June 14, 9*b818915fSFrans Kaashoek2000)). See also https://pdos.csail.mit.edu/6.828/, which 1082537b71Srtmprovides pointers to on-line resources for v6. 11b52151e0Skaashoek 1282537b71Srtmxv6 borrows code from the following sources: 1382537b71Srtm JOS (asm.h, elf.h, mmu.h, bootasm.S, ide.c, console.c, and others) 1482bb0b56SAustin Clements Plan 9 (entryother.S, mp.h, mp.c, lapic.c) 15801affcdSkaashoek FreeBSD (ioapic.c) 1682537b71Srtm NetBSD (console.c) 17801affcdSkaashoek 185bf3fbeeSFrans KaashoekThe following people have made contributions: Russ Cox (context switching, 195bf3fbeeSFrans Kaashoeklocking), Cliff Frey (MP), Xiao Yu (MP), Nickolai Zeldovich, and Austin 205bf3fbeeSFrans KaashoekClements. 21801affcdSkaashoek 225bf3fbeeSFrans KaashoekWe are also grateful for the bug reports and patches contributed by Silas 23f3048879SFrans KaashoekBoyd-Wickizer, Anton Burtsev, Cody Cutler, Mike CAT, Tej Chajed, eyalz800, 24f3048879SFrans KaashoekNelson Elhage, Saar Ettinger, Alice Ferrazzi, Nathaniel Filardo, Peter 25f3048879SFrans KaashoekFroehlich, Yakir Goaron,Shivam Handa, Bryan Henry, Jim Huang, Alexander 26f3048879SFrans KaashoekKapshuk, Anders Kaseorg, kehao95, Wolfgang Keller, Eddie Kohler, Austin 27*b818915fSFrans KaashoekLiew, Imbar Marinescu, Yandong Mao, Matan Shabtay, Hitoshi Mitake, Carmi 28f3048879SFrans KaashoekMerimovich, Mark Morrissey, mtasm, Joel Nider, Greg Price, Ayan Shafqat, 29f3048879SFrans KaashoekEldar Sehayek, Yongming Shen, Cam Tenny, tyfkda, Rafael Ubal, Warren 30f3048879SFrans KaashoekToomey, Stephen Tu, Pablo Ventura, Xi Wang, Keiichi Watanabe, Nicolas 31f3048879SFrans KaashoekWolovick, wxdao, Grant Wu, Jindong Zhang, Icenowy Zheng, and Zou Chang Wei. 327b814133SAustin Clements 33fa1b3410SrscThe code in the files that constitute xv6 is 34b2ca8e3eSFrans KaashoekCopyright 2006-2018 Frans Kaashoek, Robert Morris, and Russ Cox. 352e898063Skaashoek 362e898063SkaashoekERROR REPORTS 372e898063Skaashoek 384638cabfSRobert MorrisPlease send errors and suggestions to Frans Kaashoek and Robert Morris 394638cabfSRobert Morris(kaashoek,rtm@mit.edu). The main purpose of xv6 is as a teaching 404638cabfSRobert Morrisoperating system for MIT's 6.828, so we are more interested in 414638cabfSRobert Morrissimplifications and clarifications than new features. 42641e29c5Skaashoek 43bc54fa39SrtmBUILDING AND RUNNING XV6 444d33ef86Srsc 454638cabfSRobert MorrisTo build xv6 on an x86 ELF machine (like Linux or FreeBSD), run 464638cabfSRobert Morris"make". On non-x86 or non-ELF machines (like OS X, even on x86), you 474638cabfSRobert Morriswill need to install a cross-compiler gcc suite capable of producing 48*b818915fSFrans Kaashoekx86 ELF binaries (see https://pdos.csail.mit.edu/6.828/). 494638cabfSRobert MorrisThen run "make TOOLPREFIX=i386-jos-elf-". Now install the QEMU PC 504638cabfSRobert Morrissimulator and run "make qemu". 51