1QEMU User space emulator 2======================== 3 4Supported Operating Systems 5--------------------------- 6 7The following OS are supported in user space emulation: 8 9- Linux (referred as qemu-linux-user) 10 11- BSD (referred as qemu-bsd-user) 12 13Features 14-------- 15 16QEMU user space emulation has the following notable features: 17 18**System call translation:** 19 QEMU includes a generic system call translator. This means that the 20 parameters of the system calls can be converted to fix endianness and 21 32/64-bit mismatches between hosts and targets. IOCTLs can be 22 converted too. 23 24**POSIX signal handling:** 25 QEMU can redirect to the running program all signals coming from the 26 host (such as ``SIGALRM``), as well as synthesize signals from 27 virtual CPU exceptions (for example ``SIGFPE`` when the program 28 executes a division by zero). 29 30 QEMU relies on the host kernel to emulate most signal system calls, 31 for example to emulate the signal mask. On Linux, QEMU supports both 32 normal and real-time signals. 33 34**Threading:** 35 On Linux, QEMU can emulate the ``clone`` syscall and create a real 36 host thread (with a separate virtual CPU) for each emulated thread. 37 Note that not all targets currently emulate atomic operations 38 correctly. x86 and Arm use a global lock in order to preserve their 39 semantics. 40 41QEMU was conceived so that ultimately it can emulate itself. Although it 42is not very useful, it is an important test to show the power of the 43emulator. 44 45Linux User space emulator 46------------------------- 47 48Quick Start 49~~~~~~~~~~~ 50 51In order to launch a Linux process, QEMU needs the process executable 52itself and all the target (x86) dynamic libraries used by it. 53 54- On x86, you can just try to launch any process by using the native 55 libraries:: 56 57 qemu-i386 -L / /bin/ls 58 59 ``-L /`` tells that the x86 dynamic linker must be searched with a 60 ``/`` prefix. 61 62- Since QEMU is also a linux process, you can launch QEMU with QEMU 63 (NOTE: you can only do that if you compiled QEMU from the sources):: 64 65 qemu-i386 -L / qemu-i386 -L / /bin/ls 66 67- On non x86 CPUs, you need first to download at least an x86 glibc 68 (``qemu-runtime-i386-XXX-.tar.gz`` on the QEMU web page). Ensure that 69 ``LD_LIBRARY_PATH`` is not set:: 70 71 unset LD_LIBRARY_PATH 72 73 Then you can launch the precompiled ``ls`` x86 executable:: 74 75 qemu-i386 tests/i386/ls 76 77 You can look at ``scripts/qemu-binfmt-conf.sh`` so that QEMU is 78 automatically launched by the Linux kernel when you try to launch x86 79 executables. It requires the ``binfmt_misc`` module in the Linux 80 kernel. 81 82- The x86 version of QEMU is also included. You can try weird things 83 such as:: 84 85 qemu-i386 /usr/local/qemu-i386/bin/qemu-i386 \ 86 /usr/local/qemu-i386/bin/ls-i386 87 88Wine launch 89~~~~~~~~~~~ 90 91- Ensure that you have a working QEMU with the x86 glibc distribution 92 (see previous section). In order to verify it, you must be able to 93 do:: 94 95 qemu-i386 /usr/local/qemu-i386/bin/ls-i386 96 97- Download the binary x86 Wine install (``qemu-XXX-i386-wine.tar.gz`` 98 on the QEMU web page). 99 100- Configure Wine on your account. Look at the provided script 101 ``/usr/local/qemu-i386/bin/wine-conf.sh``. Your previous 102 ``${HOME}/.wine`` directory is saved to ``${HOME}/.wine.org``. 103 104- Then you can try the example ``putty.exe``:: 105 106 qemu-i386 /usr/local/qemu-i386/wine/bin/wine \ 107 /usr/local/qemu-i386/wine/c/Program\ Files/putty.exe 108 109Command line options 110~~~~~~~~~~~~~~~~~~~~ 111 112:: 113 114 qemu-i386 [-h] [-d] [-L path] [-s size] [-cpu model] [-g port] [-B offset] [-R size] program [arguments...] 115 116``-h`` 117 Print the help 118 119``-L path`` 120 Set the x86 elf interpreter prefix (default=/usr/local/qemu-i386) 121 122``-s size`` 123 Set the x86 stack size in bytes (default=524288) 124 125``-cpu model`` 126 Select CPU model (-cpu help for list and additional feature 127 selection) 128 129``-E var=value`` 130 Set environment var to value. 131 132``-U var`` 133 Remove var from the environment. 134 135``-B offset`` 136 Offset guest address by the specified number of bytes. This is useful 137 when the address region required by guest applications is reserved on 138 the host. This option is currently only supported on some hosts. 139 140``-R size`` 141 Pre-allocate a guest virtual address space of the given size (in 142 bytes). \"G\", \"M\", and \"k\" suffixes may be used when specifying 143 the size. 144 145Debug options: 146 147``-d item1,...`` 148 Activate logging of the specified items (use '-d help' for a list of 149 log items) 150 151``-p pagesize`` 152 Act as if the host page size was 'pagesize' bytes 153 154``-g port`` 155 Wait gdb connection to port 156 157``-singlestep`` 158 Run the emulation in single step mode. 159 160Environment variables: 161 162QEMU_STRACE 163 Print system calls and arguments similar to the 'strace' program 164 (NOTE: the actual 'strace' program will not work because the user 165 space emulator hasn't implemented ptrace). At the moment this is 166 incomplete. All system calls that don't have a specific argument 167 format are printed with information for six arguments. Many 168 flag-style arguments don't have decoders and will show up as numbers. 169 170Other binaries 171~~~~~~~~~~~~~~ 172 173user mode (Alpha) 174``qemu-alpha`` TODO. 175 176user mode (Arm) 177``qemu-armeb`` TODO. 178 179user mode (Arm) 180``qemu-arm`` is also capable of running Arm \"Angel\" semihosted ELF 181binaries (as implemented by the arm-elf and arm-eabi Newlib/GDB 182configurations), and arm-uclinux bFLT format binaries. 183 184user mode (ColdFire) 185user mode (M68K) 186``qemu-m68k`` is capable of running semihosted binaries using the BDM 187(m5xxx-ram-hosted.ld) or m68k-sim (sim.ld) syscall interfaces, and 188coldfire uClinux bFLT format binaries. 189 190The binary format is detected automatically. 191 192user mode (Cris) 193``qemu-cris`` TODO. 194 195user mode (i386) 196``qemu-i386`` TODO. ``qemu-x86_64`` TODO. 197 198user mode (Microblaze) 199``qemu-microblaze`` TODO. 200 201user mode (MIPS) 202``qemu-mips`` executes 32-bit big endian MIPS binaries (MIPS O32 ABI). 203 204``qemu-mipsel`` executes 32-bit little endian MIPS binaries (MIPS O32 205ABI). 206 207``qemu-mips64`` executes 64-bit big endian MIPS binaries (MIPS N64 ABI). 208 209``qemu-mips64el`` executes 64-bit little endian MIPS binaries (MIPS N64 210ABI). 211 212``qemu-mipsn32`` executes 32-bit big endian MIPS binaries (MIPS N32 213ABI). 214 215``qemu-mipsn32el`` executes 32-bit little endian MIPS binaries (MIPS N32 216ABI). 217 218user mode (NiosII) 219``qemu-nios2`` TODO. 220 221user mode (PowerPC) 222``qemu-ppc64abi32`` TODO. ``qemu-ppc64`` TODO. ``qemu-ppc`` TODO. 223 224user mode (SH4) 225``qemu-sh4eb`` TODO. ``qemu-sh4`` TODO. 226 227user mode (SPARC) 228``qemu-sparc`` can execute Sparc32 binaries (Sparc32 CPU, 32 bit ABI). 229 230``qemu-sparc32plus`` can execute Sparc32 and SPARC32PLUS binaries 231(Sparc64 CPU, 32 bit ABI). 232 233``qemu-sparc64`` can execute some Sparc64 (Sparc64 CPU, 64 bit ABI) and 234SPARC32PLUS binaries (Sparc64 CPU, 32 bit ABI). 235 236BSD User space emulator 237----------------------- 238 239BSD Status 240~~~~~~~~~~ 241 242- target Sparc64 on Sparc64: Some trivial programs work. 243 244Quick Start 245~~~~~~~~~~~ 246 247In order to launch a BSD process, QEMU needs the process executable 248itself and all the target dynamic libraries used by it. 249 250- On Sparc64, you can just try to launch any process by using the 251 native libraries:: 252 253 qemu-sparc64 /bin/ls 254 255Command line options 256~~~~~~~~~~~~~~~~~~~~ 257 258:: 259 260 qemu-sparc64 [-h] [-d] [-L path] [-s size] [-bsd type] program [arguments...] 261 262``-h`` 263 Print the help 264 265``-L path`` 266 Set the library root path (default=/) 267 268``-s size`` 269 Set the stack size in bytes (default=524288) 270 271``-ignore-environment`` 272 Start with an empty environment. Without this option, the initial 273 environment is a copy of the caller's environment. 274 275``-E var=value`` 276 Set environment var to value. 277 278``-U var`` 279 Remove var from the environment. 280 281``-bsd type`` 282 Set the type of the emulated BSD Operating system. Valid values are 283 FreeBSD, NetBSD and OpenBSD (default). 284 285Debug options: 286 287``-d item1,...`` 288 Activate logging of the specified items (use '-d help' for a list of 289 log items) 290 291``-p pagesize`` 292 Act as if the host page size was 'pagesize' bytes 293 294``-singlestep`` 295 Run the emulation in single step mode. 296