# Linux Compatibility

> "We don't break user space."
>
> --- Linus Torvalds

Asterinas is dedicated to maintaining compatibility with the Linux ABI,
ensuring that applications and administrative tools
designed for Linux can seamlessly operate within Asterinas.
While we prioritize compatibility,
it is important to note that Asterinas does not,
nor will it in the future,
support the loading of Linux kernel modules.

## System Calls

At the time of writing,
Asterinas implements 204 out of the 336 system calls
provided by Linux on x86-64 architecture.

| Numbers | Names            | Is Implemented  |
| ------- | ---------------- | --------------- |
| 0       | read             | ✅              |
| 1       | write            | ✅              |
| 2       | open             | ✅              |
| 3       | close            | ✅              |
| 4       | stat             | ✅              |
| 5       | fstat            | ✅              |
| 6       | lstat            | ✅              |
| 7       | poll             | ✅              |
| 8       | lseek            | ✅              |
| 9       | mmap             | ✅              |
| 10      | mprotect         | ✅              |
| 11      | munmap           | ✅              |
| 12      | brk              | ✅              |
| 13      | rt_sigaction     | ✅              |
| 14      | rt_sigprocmask   | ✅              |
| 15      | rt_sigreturn     | ✅              |
| 16      | ioctl            | ✅              |
| 17      | pread64          | ✅              |
| 18      | pwrite64         | ✅              |
| 19      | readv            | ✅              |
| 20      | writev           | ✅              |
| 21      | access           | ✅              |
| 22      | pipe             | ✅              |
| 23      | select           | ✅              |
| 24      | sched_yield      | ✅              |
| 25      | mremap           | ❌              |
| 26      | msync            | ❌              |
| 27      | mincore          | ❌              |
| 28      | madvise          | ✅              |
| 29      | shmget           | ❌              |
| 30      | shmat            | ❌              |
| 31      | shmctl           | ❌              |
| 32      | dup              | ✅              |
| 33      | dup2             | ✅              |
| 34      | pause            | ✅              |
| 35      | nanosleep        | ✅              |
| 36      | getitimer        | ✅              |
| 37      | alarm            | ✅              |
| 38      | setitimer        | ✅              |
| 39      | getpid           | ✅              |
| 40      | sendfile         | ✅              |
| 41      | socket           | ✅              |
| 42      | connect          | ✅              |
| 43      | accept           | ✅              |
| 44      | sendto           | ✅              |
| 45      | recvfrom         | ✅              |
| 46      | sendmsg          | ✅              |
| 47      | recvmsg          | ✅              |
| 48      | shutdown         | ✅              |
| 49      | bind             | ✅              |
| 50      | listen           | ✅              |
| 51      | getsockname      | ✅              |
| 52      | getpeername      | ✅              |
| 53      | socketpair       | ✅              |
| 54      | setsockopt       | ✅              |
| 55      | getsockopt       | ✅              |
| 56      | clone            | ✅              |
| 57      | fork             | ✅              |
| 58      | vfork            | ❌              |
| 59      | execve           | ✅              |
| 60      | exit             | ✅              |
| 61      | wait4            | ✅              |
| 62      | kill             | ✅              |
| 63      | uname            | ✅              |
| 64      | semget           | ✅              |
| 65      | semop            | ✅              |
| 66      | semctl           | ✅              |
| 67      | shmdt            | ❌              |
| 68      | msgget           | ❌              |
| 69      | msgsnd           | ❌              |
| 70      | msgrcv           | ❌              |
| 71      | msgctl           | ❌              |
| 72      | fcntl            | ✅              |
| 73      | flock            | ✅              |
| 74      | fsync            | ✅              |
| 75      | fdatasync        | ✅              |
| 76      | truncate         | ✅              |
| 77      | ftruncate        | ✅              |
| 78      | getdents         | ✅              |
| 79      | getcwd           | ✅              |
| 80      | chdir            | ✅              |
| 81      | fchdir           | ✅              |
| 82      | rename           | ✅              |
| 83      | mkdir            | ✅              |
| 84      | rmdir            | ✅              |
| 85      | creat            | ✅              |
| 86      | link             | ✅              |
| 87      | unlink           | ✅              |
| 88      | symlink          | ✅              |
| 89      | readlink         | ✅              |
| 90      | chmod            | ✅              |
| 91      | fchmod           | ✅              |
| 92      | chown            | ✅              |
| 93      | fchown           | ✅              |
| 94      | lchown           | ✅              |
| 95      | umask            | ✅              |
| 96      | gettimeofday     | ✅              |
| 97      | getrlimit        | ✅              |
| 98      | getrusage        | ✅              |
| 99      | sysinfo          | ✅              |
| 100     | times            | ❌              |
| 101     | ptrace           | ❌              |
| 102     | getuid           | ✅              |
| 103     | syslog           | ❌              |
| 104     | getgid           | ✅              |
| 105     | setuid           | ✅              |
| 106     | setgid           | ✅              |
| 107     | geteuid          | ✅              |
| 108     | getegid          | ✅              |
| 109     | setpgid          | ✅              |
| 110     | getppid          | ✅              |
| 111     | getpgrp          | ✅              |
| 112     | setsid           | ✅              |
| 113     | setreuid         | ✅              |
| 114     | setregid         | ✅              |
| 115     | getgroups        | ✅              |
| 116     | setgroups        | ✅              |
| 117     | setresuid        | ✅              |
| 118     | getresuid        | ✅              |
| 119     | setresgid        | ✅              |
| 120     | getresgid        | ✅              |
| 121     | getpgid          | ✅              |
| 122     | setfsuid         | ✅              |
| 123     | setfsgid         | ✅              |
| 124     | getsid           | ✅              |
| 125     | capget           | ✅              |
| 126     | capset           | ✅              |
| 127     | rt_sigpending    | ✅              |
| 128     | rt_sigtimedwait  | ❌              |
| 129     | rt_sigqueueinfo  | ❌              |
| 130     | rt_sigsuspend    | ✅              |
| 131     | sigaltstack      | ✅              |
| 132     | utime            | ✅              |
| 133     | mknod            | ✅              |
| 134     | uselib           | ❌              |
| 135     | personality      | ❌              |
| 136     | ustat            | ❌              |
| 137     | statfs           | ✅              |
| 138     | fstatfs          | ✅              |
| 139     | sysfs            | ❌              |
| 140     | getpriority      | ✅              |
| 141     | setpriority      | ✅              |
| 142     | sched_setparam   | ✅              |
| 143     | sched_getparam   | ✅              |
| 144     | sched_setscheduler | ✅            |
| 145     | sched_getscheduler | ✅            |
| 146     | sched_get_priority_max | ✅        |
| 147     | sched_get_priority_min | ✅        |
| 148     | sched_rr_get_interval | ❌         |
| 149     | mlock            | ❌              |
| 150     | munlock          | ❌              |
| 151     | mlockall         | ❌              |
| 152     | munlockall       | ❌              |
| 153     | vhangup          | ❌              |
| 154     | modify_ldt       | ❌              |
| 155     | pivot_root       | ❌              |
| 156     | _sysctl          | ❌              |
| 157     | prctl            | ✅              |
| 158     | arch_prctl       | ✅              |
| 159     | adjtimex         | ❌              |
| 160     | setrlimit        | ✅              |
| 161     | chroot           | ✅              |
| 162     | sync             | ✅              |
| 163     | acct             | ❌              |
| 164     | settimeofday     | ❌              |
| 165     | mount            | ✅              |
| 166     | umount2          | ✅              |
| 167     | swapon           | ❌              |
| 168     | swapoff          | ❌              |
| 169     | reboot           | ❌              |
| 170     | sethostname      | ❌              |
| 171     | setdomainname    | ❌              |
| 172     | iopl             | ❌              |
| 173     | ioperm           | ❌              |
| 174     | create_module    | ❌              |
| 175     | init_module      | ❌              |
| 176     | delete_module    | ❌              |
| 177     | get_kernel_syms  | ❌              |
| 178     | query_module     | ❌              |
| 179     | quotactl         | ❌              |
| 180     | nfsservctl       | ❌              |
| 181     | getpmsg          | ❌              |
| 182     | putpmsg          | ❌              |
| 183     | afs_syscall      | ❌              |
| 184     | tuxcall          | ❌              |
| 185     | security         | ❌              |
| 186     | gettid           | ✅              |
| 187     | readahead        | ❌              |
| 188     | setxattr         | ✅              |
| 189     | lsetxattr        | ✅              |
| 190     | fsetxattr        | ✅              |
| 191     | getxattr         | ✅              |
| 192     | lgetxattr        | ✅              |
| 193     | fgetxattr        | ✅              |
| 194     | listxattr        | ✅              |
| 195     | llistxattr       | ✅              |
| 196     | flistxattr       | ✅              |
| 197     | removexattr      | ✅              |
| 198     | lremovexattr     | ✅              |
| 199     | fremovexattr     | ✅              |
| 200     | tkill            | ❌              |
| 201     | time             | ✅              |
| 202     | futex            | ✅              |
| 203     | sched_setaffinity | ✅             |
| 204     | sched_getaffinity | ✅             |
| 205     | set_thread_area  | ❌              |
| 206     | io_setup         | ❌              |
| 207     | io_destroy       | ❌              |
| 208     | io_getevents     | ❌              |
| 209     | io_submit        | ❌              |
| 210     | io_cancel        | ❌              |
| 211     | get_thread_area  | ❌              |
| 212     | lookup_dcookie   | ❌              |
| 213     | epoll_create     | ✅              |
| 214     | epoll_ctl_old    | ❌              |
| 215     | epoll_wait_old   | ❌              |
| 216     | remap_file_pages | ❌              |
| 217     | getdents64       | ✅              |
| 218     | set_tid_address  | ✅              |
| 219     | restart_syscall  | ❌              |
| 220     | semtimedop       | ✅              |
| 221     | fadvise64        | ❌              |
| 222     | timer_create     | ✅              |
| 223     | timer_settime    | ✅              |
| 224     | timer_gettime    | ✅              |
| 225     | timer_getoverrun | ❌              |
| 226     | timer_delete     | ✅              |
| 227     | clock_settime    | ❌              |
| 228     | clock_gettime    | ✅              |
| 229     | clock_getres     | ❌              |
| 230     | clock_nanosleep  | ✅              |
| 231     | exit_group       | ✅              |
| 232     | epoll_wait       | ✅              |
| 233     | epoll_ctl        | ✅              |
| 234     | tgkill           | ✅              |
| 235     | utimes           | ✅              |
| 236     | vserver          | ❌              |
| 237     | mbind            | ❌              |
| 238     | set_mempolicy    | ❌              |
| 239     | get_mempolicy    | ❌              |
| 240     | mq_open          | ❌              |
| 241     | mq_unlink        | ❌              |
| 242     | mq_timedsend     | ❌              |
| 243     | mq_timedreceive  | ❌              |
| 244     | mq_notify        | ❌              |
| 245     | mq_getsetattr    | ❌              |
| 246     | kexec_load       | ❌              |
| 247     | waitid           | ✅              |
| 248     | add_key          | ❌              |
| 249     | request_key      | ❌              |
| 250     | keyctl           | ❌              |
| 251     | ioprio_set       | ❌              |
| 252     | ioprio_get       | ❌              |
| 253     | inotify_init     | ❌              |
| 254     | inotify_add_watch | ❌             |
| 255     | inotify_rm_watch | ❌              |
| 256     | migrate_pages    | ❌              |
| 257     | openat           | ✅              |
| 258     | mkdirat          | ✅              |
| 259     | mknodat          | ✅              |
| 260     | fchownat         | ✅              |
| 261     | futimesat        | ✅              |
| 262     | newfstatat       | ✅              |
| 263     | unlinkat         | ✅              |
| 264     | renameat         | ✅              |
| 265     | linkat           | ✅              |
| 266     | symlinkat        | ✅              |
| 267     | readlinkat       | ✅              |
| 268     | fchmodat         | ✅              |
| 269     | faccessat        | ✅              |
| 270     | pselect6         | ✅              |
| 271     | ppoll            | ✅              |
| 272     | unshare          | ❌              |
| 273     | set_robust_list  | ✅              |
| 274     | get_robust_list  | ❌              |
| 275     | splice           | ❌              |
| 276     | tee              | ❌              |
| 277     | sync_file_range  | ❌              |
| 278     | vmsplice         | ❌              |
| 279     | move_pages       | ❌              |
| 280     | utimensat        | ✅              |
| 281     | epoll_pwait      | ✅              |
| 282     | signalfd         | ✅              |
| 283     | timerfd_create   | ✅              |
| 284     | eventfd          | ✅              |
| 285     | fallocate        | ✅              |
| 286     | timerfd_settime  | ✅              |
| 287     | timerfd_gettime  | ✅              |
| 288     | accept4          | ✅              |
| 289     | signalfd4        | ✅              |
| 290     | eventfd2         | ✅              |
| 291     | epoll_create1    | ✅              |
| 292     | dup3             | ✅              |
| 293     | pipe2            | ✅              |
| 294     | inotify_init1    | ❌              |
| 295     | preadv           | ✅              |
| 296     | pwritev          | ✅              |
| 297     | rt_tgsigqueueinfo | ❌             |
| 298     | perf_event_open  | ❌              |
| 299     | recvmmsg         | ❌              |
| 300     | fanotify_init    | ❌              |
| 301     | fanotify_mark    | ❌              | 
| 302	  | prlimit64        | ✅              |
| 303	  | name_to_handle_at | ❌              |
| 304	  | open_by_handle_at | ❌              |	
| 305	  | clock_adjtime    | ❌              |
| 306	  | syncfs           | ❌              |
| 307	  | sendmmsg         | ❌              |
| 308	  | setns            | ❌              |
| 309	  | getcpu	         | ✅              |
| 310	  | process_vm_readv | ❌              |
| 311	  | process_vm_writev | ❌              |
| 312	  | kcmp             | ❌              |
| 313	  | finit_module     | ❌              |
| 314	  | sched_setattr    | ✅              |
| 315	  | sched_getattr    | ✅              |
| 318	  | getrandom        | ✅              |
| 322	  | execveat         | ✅              |
| 327	  | preadv2          | ✅              |
| 328	  | pwritev2         | ✅              |
| 332     | statx            | ✅              |
| 435	  | clone3           | ✅              |
| 439     | faccessat2       | ✅              |

## File Systems

Here is the list of supported file systems:
* Devfs
* Devpts
* Ext2
* Procfs
* Ramfs

## Sockets

Here is the list of supported socket types:
* TCP sockets over IPv4
* UDP sockets over IPv4
* Unix sockets

## vDSO

Here is the list of supported symbols in vDSO:
* `__vdso_clock_gettime`
* `__vdso_gettimeofday`
* `__vdso_time`

## Boot Protocols

Here is the list of supported boot protocols:
* [Multiboot](https://www.gnu.org/software/grub/manual/multiboot/multiboot.html)
* [Multiboot2](https://www.gnu.org/software/grub/manual/multiboot2/multiboot.html)
* [Linux 32-bit boot protocol](https://www.kernel.org/doc/html/v5.4/x86/boot.html#bit-boot-protocol)
* [Linux EFI handover](https://www.kernel.org/doc/html/v5.4/x86/boot.html#efi-handover-protocol)
