1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD 3 * 4 * Copyright (c) 1994-1996 Søren Schmidt 5 * Copyright (c) 2018 Turing Robotic Industries Inc. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 * SUCH DAMAGE. 27 */ 28 29 #include <sys/cdefs.h> 30 __FBSDID("$FreeBSD$"); 31 32 #include <sys/param.h> 33 #include <sys/systm.h> 34 #include <sys/cdefs.h> 35 #include <sys/elf.h> 36 #include <sys/exec.h> 37 #include <sys/imgact.h> 38 #include <sys/imgact_elf.h> 39 #include <sys/kernel.h> 40 #include <sys/lock.h> 41 #include <sys/module.h> 42 #include <sys/mutex.h> 43 #include <sys/proc.h> 44 #include <sys/signalvar.h> 45 #include <sys/sysctl.h> 46 #include <sys/sysent.h> 47 48 #include <vm/vm_param.h> 49 50 #include <arm64/linux/linux.h> 51 #include <arm64/linux/linux_proto.h> 52 #include <compat/linux/linux_dtrace.h> 53 #include <compat/linux/linux_emul.h> 54 #include <compat/linux/linux_ioctl.h> 55 #include <compat/linux/linux_mib.h> 56 #include <compat/linux/linux_misc.h> 57 #include <compat/linux/linux_util.h> 58 #include <compat/linux/linux_vdso.h> 59 60 #include <machine/md_var.h> 61 62 #ifdef VFP 63 #include <machine/vfp.h> 64 #endif 65 66 MODULE_VERSION(linux64elf, 1); 67 68 const char *linux_kplatform; 69 static int linux_szsigcode; 70 static vm_object_t linux_shared_page_obj; 71 static char *linux_shared_page_mapping; 72 extern char _binary_linux_locore_o_start; 73 extern char _binary_linux_locore_o_end; 74 75 extern struct sysent linux_sysent[LINUX_SYS_MAXSYSCALL]; 76 77 SET_DECLARE(linux_ioctl_handler_set, struct linux_ioctl_handler); 78 79 static int linux_copyout_strings(struct image_params *imgp, 80 uintptr_t *stack_base); 81 static int linux_elf_fixup(uintptr_t *stack_base, 82 struct image_params *iparams); 83 static bool linux_trans_osrel(const Elf_Note *note, int32_t *osrel); 84 static void linux_vdso_install(const void *param); 85 static void linux_vdso_deinstall(const void *param); 86 static void linux_set_syscall_retval(struct thread *td, int error); 87 static int linux_fetch_syscall_args(struct thread *td); 88 static void linux_exec_setregs(struct thread *td, struct image_params *imgp, 89 uintptr_t stack); 90 static int linux_vsyscall(struct thread *td); 91 92 /* DTrace init */ 93 LIN_SDT_PROVIDER_DECLARE(LINUX_DTRACE); 94 95 /* DTrace probes */ 96 LIN_SDT_PROBE_DEFINE2(sysvec, linux_translate_traps, todo, "int", "int"); 97 LIN_SDT_PROBE_DEFINE0(sysvec, linux_exec_setregs, todo); 98 LIN_SDT_PROBE_DEFINE0(sysvec, linux_copyout_auxargs, todo); 99 LIN_SDT_PROBE_DEFINE0(sysvec, linux_elf_fixup, todo); 100 LIN_SDT_PROBE_DEFINE0(sysvec, linux_rt_sigreturn, todo); 101 LIN_SDT_PROBE_DEFINE0(sysvec, linux_rt_sendsig, todo); 102 LIN_SDT_PROBE_DEFINE0(sysvec, linux_vsyscall, todo); 103 LIN_SDT_PROBE_DEFINE0(sysvec, linux_vdso_install, todo); 104 LIN_SDT_PROBE_DEFINE0(sysvec, linux_vdso_deinstall, todo); 105 106 /* LINUXTODO: do we have traps to translate? */ 107 static int 108 linux_translate_traps(int signal, int trap_code) 109 { 110 111 LIN_SDT_PROBE2(sysvec, linux_translate_traps, todo, signal, trap_code); 112 return (signal); 113 } 114 115 LINUX_VDSO_SYM_CHAR(linux_platform); 116 117 static int 118 linux_fetch_syscall_args(struct thread *td) 119 { 120 struct proc *p; 121 struct syscall_args *sa; 122 register_t *ap; 123 124 p = td->td_proc; 125 ap = td->td_frame->tf_x; 126 sa = &td->td_sa; 127 128 sa->code = td->td_frame->tf_x[8]; 129 /* LINUXTODO: generic syscall? */ 130 if (sa->code >= p->p_sysent->sv_size) 131 sa->callp = &p->p_sysent->sv_table[0]; 132 else 133 sa->callp = &p->p_sysent->sv_table[sa->code]; 134 135 if (sa->callp->sy_narg > MAXARGS) 136 panic("ARM64TODO: Could we have more than %d args?", MAXARGS); 137 memcpy(sa->args, ap, MAXARGS * sizeof(register_t)); 138 139 td->td_retval[0] = 0; 140 return (0); 141 } 142 143 static void 144 linux_set_syscall_retval(struct thread *td, int error) 145 { 146 147 td->td_retval[1] = td->td_frame->tf_x[1]; 148 cpu_set_syscall_retval(td, error); 149 150 if (__predict_false(error != 0)) { 151 if (error != ERESTART && error != EJUSTRETURN) 152 td->td_frame->tf_x[0] = bsd_to_linux_errno(error); 153 } 154 } 155 156 static int 157 linux_copyout_auxargs(struct image_params *imgp, uintptr_t base) 158 { 159 Elf_Auxargs *args; 160 Elf_Auxinfo *argarray, *pos; 161 struct proc *p; 162 int error, issetugid; 163 164 LIN_SDT_PROBE0(sysvec, linux_copyout_auxargs, todo); 165 p = imgp->proc; 166 167 args = (Elf64_Auxargs *)imgp->auxargs; 168 argarray = pos = malloc(LINUX_AT_COUNT * sizeof(*pos), M_TEMP, 169 M_WAITOK | M_ZERO); 170 171 issetugid = p->p_flag & P_SUGID ? 1 : 0; 172 AUXARGS_ENTRY(pos, LINUX_AT_SYSINFO_EHDR, 173 imgp->proc->p_sysent->sv_shared_page_base); 174 AUXARGS_ENTRY(pos, LINUX_AT_HWCAP, *imgp->sysent->sv_hwcap); 175 AUXARGS_ENTRY(pos, AT_PAGESZ, args->pagesz); 176 AUXARGS_ENTRY(pos, LINUX_AT_CLKTCK, stclohz); 177 AUXARGS_ENTRY(pos, AT_PHDR, args->phdr); 178 AUXARGS_ENTRY(pos, AT_PHENT, args->phent); 179 AUXARGS_ENTRY(pos, AT_PHNUM, args->phnum); 180 AUXARGS_ENTRY(pos, AT_BASE, args->base); 181 AUXARGS_ENTRY(pos, AT_FLAGS, args->flags); 182 AUXARGS_ENTRY(pos, AT_ENTRY, args->entry); 183 AUXARGS_ENTRY(pos, AT_UID, imgp->proc->p_ucred->cr_ruid); 184 AUXARGS_ENTRY(pos, AT_EUID, imgp->proc->p_ucred->cr_svuid); 185 AUXARGS_ENTRY(pos, AT_GID, imgp->proc->p_ucred->cr_rgid); 186 AUXARGS_ENTRY(pos, AT_EGID, imgp->proc->p_ucred->cr_svgid); 187 AUXARGS_ENTRY(pos, LINUX_AT_SECURE, issetugid); 188 AUXARGS_ENTRY_PTR(pos, LINUX_AT_RANDOM, imgp->canary); 189 AUXARGS_ENTRY(pos, LINUX_AT_HWCAP2, *imgp->sysent->sv_hwcap2); 190 if (imgp->execpathp != 0) 191 AUXARGS_ENTRY_PTR(pos, LINUX_AT_EXECFN, imgp->execpathp); 192 if (args->execfd != -1) 193 AUXARGS_ENTRY(pos, AT_EXECFD, args->execfd); 194 AUXARGS_ENTRY(pos, LINUX_AT_PLATFORM, PTROUT(linux_platform)); 195 AUXARGS_ENTRY(pos, AT_NULL, 0); 196 197 free(imgp->auxargs, M_TEMP); 198 imgp->auxargs = NULL; 199 KASSERT(pos - argarray <= LINUX_AT_COUNT, ("Too many auxargs")); 200 201 error = copyout(argarray, (void *)base, 202 sizeof(*argarray) * LINUX_AT_COUNT); 203 free(argarray, M_TEMP); 204 return (error); 205 } 206 207 static int 208 linux_elf_fixup(uintptr_t *stack_base, struct image_params *imgp) 209 { 210 211 LIN_SDT_PROBE0(sysvec, linux_elf_fixup, todo); 212 213 return (0); 214 } 215 216 /* 217 * Copy strings out to the new process address space, constructing new arg 218 * and env vector tables. Return a pointer to the base so that it can be used 219 * as the initial stack pointer. 220 * LINUXTODO: deduplicate against other linuxulator archs 221 */ 222 static int 223 linux_copyout_strings(struct image_params *imgp, uintptr_t *stack_base) 224 { 225 char **vectp; 226 char *stringp; 227 uintptr_t destp, ustringp; 228 struct ps_strings *arginfo; 229 char canary[LINUX_AT_RANDOM_LEN]; 230 size_t execpath_len; 231 struct proc *p; 232 int argc, envc, error; 233 234 /* Calculate string base and vector table pointers. */ 235 if (imgp->execpath != NULL && imgp->auxargs != NULL) 236 execpath_len = strlen(imgp->execpath) + 1; 237 else 238 execpath_len = 0; 239 240 p = imgp->proc; 241 arginfo = (struct ps_strings *)p->p_sysent->sv_psstrings; 242 destp = (uintptr_t)arginfo; 243 244 if (execpath_len != 0) { 245 destp -= execpath_len; 246 destp = rounddown2(destp, sizeof(void *)); 247 imgp->execpathp = (void *)destp; 248 error = copyout(imgp->execpath, imgp->execpathp, execpath_len); 249 if (error != 0) 250 return (error); 251 } 252 253 /* Prepare the canary for SSP. */ 254 arc4rand(canary, sizeof(canary), 0); 255 destp -= roundup(sizeof(canary), sizeof(void *)); 256 imgp->canary = (void *)destp; 257 error = copyout(canary, imgp->canary, sizeof(canary)); 258 if (error != 0) 259 return (error); 260 261 /* Allocate room for the argument and environment strings. */ 262 destp -= ARG_MAX - imgp->args->stringspace; 263 destp = rounddown2(destp, sizeof(void *)); 264 ustringp = destp; 265 266 if (imgp->auxargs) { 267 /* 268 * Allocate room on the stack for the ELF auxargs 269 * array. It has up to LINUX_AT_COUNT entries. 270 */ 271 destp -= LINUX_AT_COUNT * sizeof(Elf64_Auxinfo); 272 destp = rounddown2(destp, sizeof(void *)); 273 } 274 275 vectp = (char **)destp; 276 277 /* 278 * Allocate room for argc and the argv[] and env vectors including the 279 * terminating NULL pointers. 280 */ 281 vectp -= 1 + imgp->args->argc + 1 + imgp->args->envc + 1; 282 vectp = (char **)STACKALIGN(vectp); 283 284 /* vectp also becomes our initial stack base. */ 285 *stack_base = (uintptr_t)vectp; 286 287 stringp = imgp->args->begin_argv; 288 argc = imgp->args->argc; 289 envc = imgp->args->envc; 290 291 /* Copy out strings - arguments and environment. */ 292 error = copyout(stringp, (void *)ustringp, 293 ARG_MAX - imgp->args->stringspace); 294 if (error != 0) 295 return (error); 296 297 /* Fill in "ps_strings" struct for ps, w, etc. */ 298 if (suword(&arginfo->ps_argvstr, (long)(intptr_t)vectp) != 0 || 299 suword(&arginfo->ps_nargvstr, argc) != 0) 300 return (EFAULT); 301 302 if (suword(vectp++, argc) != 0) 303 return (EFAULT); 304 305 /* Fill in argument portion of vector table. */ 306 for (; argc > 0; --argc) { 307 if (suword(vectp++, ustringp) != 0) 308 return (EFAULT); 309 while (*stringp++ != 0) 310 ustringp++; 311 ustringp++; 312 } 313 314 /* A null vector table pointer separates the argp's from the envp's. */ 315 if (suword(vectp++, 0) != 0) 316 return (EFAULT); 317 318 if (suword(&arginfo->ps_envstr, (long)(intptr_t)vectp) != 0 || 319 suword(&arginfo->ps_nenvstr, envc) != 0) 320 return (EFAULT); 321 322 /* Fill in environment portion of vector table. */ 323 for (; envc > 0; --envc) { 324 if (suword(vectp++, ustringp) != 0) 325 return (EFAULT); 326 while (*stringp++ != 0) 327 ustringp++; 328 ustringp++; 329 } 330 331 /* The end of the vector table is a null pointer. */ 332 if (suword(vectp, 0) != 0) 333 return (EFAULT); 334 335 if (imgp->auxargs) { 336 vectp++; 337 error = imgp->sysent->sv_copyout_auxargs(imgp, 338 (uintptr_t)vectp); 339 if (error != 0) 340 return (error); 341 } 342 343 return (0); 344 } 345 346 /* 347 * Reset registers to default values on exec. 348 */ 349 static void 350 linux_exec_setregs(struct thread *td, struct image_params *imgp, 351 uintptr_t stack) 352 { 353 struct trapframe *regs = td->td_frame; 354 struct pcb *pcb = td->td_pcb; 355 356 /* LINUXTODO: validate */ 357 LIN_SDT_PROBE0(sysvec, linux_exec_setregs, todo); 358 359 memset(regs, 0, sizeof(*regs)); 360 /* glibc start.S registers function pointer in x0 with atexit. */ 361 regs->tf_sp = stack; 362 #if 0 /* LINUXTODO: See if this is used. */ 363 regs->tf_lr = imgp->entry_addr; 364 #else 365 regs->tf_lr = 0xffffffffffffffff; 366 #endif 367 regs->tf_elr = imgp->entry_addr; 368 369 pcb->pcb_tpidr_el0 = 0; 370 pcb->pcb_tpidrro_el0 = 0; 371 WRITE_SPECIALREG(tpidrro_el0, 0); 372 WRITE_SPECIALREG(tpidr_el0, 0); 373 374 #ifdef VFP 375 vfp_reset_state(td, pcb); 376 #endif 377 378 /* 379 * Clear debug register state. It is not applicable to the new process. 380 */ 381 bzero(&pcb->pcb_dbg_regs, sizeof(pcb->pcb_dbg_regs)); 382 } 383 384 int 385 linux_rt_sigreturn(struct thread *td, struct linux_rt_sigreturn_args *args) 386 { 387 388 /* LINUXTODO: implement */ 389 LIN_SDT_PROBE0(sysvec, linux_rt_sigreturn, todo); 390 return (EDOOFUS); 391 } 392 393 static void 394 linux_rt_sendsig(sig_t catcher, ksiginfo_t *ksi, sigset_t *mask) 395 { 396 397 /* LINUXTODO: implement */ 398 LIN_SDT_PROBE0(sysvec, linux_rt_sendsig, todo); 399 } 400 401 static int 402 linux_vsyscall(struct thread *td) 403 { 404 405 /* LINUXTODO: implement */ 406 LIN_SDT_PROBE0(sysvec, linux_vsyscall, todo); 407 return (EDOOFUS); 408 } 409 410 struct sysentvec elf_linux_sysvec = { 411 .sv_size = LINUX_SYS_MAXSYSCALL, 412 .sv_table = linux_sysent, 413 .sv_transtrap = linux_translate_traps, 414 .sv_fixup = linux_elf_fixup, 415 .sv_sendsig = linux_rt_sendsig, 416 .sv_sigcode = &_binary_linux_locore_o_start, 417 .sv_szsigcode = &linux_szsigcode, 418 .sv_name = "Linux ELF64", 419 .sv_coredump = elf64_coredump, 420 .sv_imgact_try = linux_exec_imgact_try, 421 .sv_minsigstksz = LINUX_MINSIGSTKSZ, 422 .sv_minuser = VM_MIN_ADDRESS, 423 .sv_maxuser = VM_MAXUSER_ADDRESS, 424 .sv_usrstack = USRSTACK, 425 .sv_psstrings = PS_STRINGS, /* XXX */ 426 .sv_stackprot = VM_PROT_READ | VM_PROT_WRITE, 427 .sv_copyout_auxargs = linux_copyout_auxargs, 428 .sv_copyout_strings = linux_copyout_strings, 429 .sv_setregs = linux_exec_setregs, 430 .sv_fixlimit = NULL, 431 .sv_maxssiz = NULL, 432 .sv_flags = SV_ABI_LINUX | SV_LP64 | SV_SHP, 433 .sv_set_syscall_retval = linux_set_syscall_retval, 434 .sv_fetch_syscall_args = linux_fetch_syscall_args, 435 .sv_syscallnames = NULL, 436 .sv_shared_page_base = SHAREDPAGE, 437 .sv_shared_page_len = PAGE_SIZE, 438 .sv_schedtail = linux_schedtail, 439 .sv_thread_detach = linux_thread_detach, 440 .sv_trap = linux_vsyscall, 441 .sv_hwcap = &elf_hwcap, 442 .sv_hwcap2 = &elf_hwcap2, 443 .sv_onexec = linux_on_exec, 444 .sv_onexit = linux_on_exit, 445 .sv_ontdexit = linux_thread_dtor, 446 .sv_setid_allowed = &linux_setid_allowed_query, 447 }; 448 449 static void 450 linux_vdso_install(const void *param) 451 { 452 453 linux_szsigcode = (&_binary_linux_locore_o_end - 454 &_binary_linux_locore_o_start); 455 456 if (linux_szsigcode > elf_linux_sysvec.sv_shared_page_len) 457 panic("invalid Linux VDSO size\n"); 458 459 __elfN(linux_vdso_fixup)(&elf_linux_sysvec); 460 461 linux_shared_page_obj = __elfN(linux_shared_page_init) 462 (&linux_shared_page_mapping); 463 464 __elfN(linux_vdso_reloc)(&elf_linux_sysvec); 465 466 memcpy(linux_shared_page_mapping, elf_linux_sysvec.sv_sigcode, 467 linux_szsigcode); 468 elf_linux_sysvec.sv_shared_page_obj = linux_shared_page_obj; 469 470 linux_kplatform = linux_shared_page_mapping + 471 (linux_platform - (caddr_t)elf_linux_sysvec.sv_shared_page_base); 472 } 473 SYSINIT(elf_linux_vdso_init, SI_SUB_EXEC, SI_ORDER_ANY, 474 linux_vdso_install, NULL); 475 476 static void 477 linux_vdso_deinstall(const void *param) 478 { 479 480 LIN_SDT_PROBE0(sysvec, linux_vdso_deinstall, todo); 481 __elfN(linux_shared_page_fini)(linux_shared_page_obj, 482 linux_shared_page_mapping); 483 } 484 SYSUNINIT(elf_linux_vdso_uninit, SI_SUB_EXEC, SI_ORDER_FIRST, 485 linux_vdso_deinstall, NULL); 486 487 static char GNU_ABI_VENDOR[] = "GNU"; 488 static int GNU_ABI_LINUX = 0; 489 490 /* LINUXTODO: deduplicate */ 491 static bool 492 linux_trans_osrel(const Elf_Note *note, int32_t *osrel) 493 { 494 const Elf32_Word *desc; 495 uintptr_t p; 496 497 p = (uintptr_t)(note + 1); 498 p += roundup2(note->n_namesz, sizeof(Elf32_Addr)); 499 500 desc = (const Elf32_Word *)p; 501 if (desc[0] != GNU_ABI_LINUX) 502 return (false); 503 504 *osrel = LINUX_KERNVER(desc[1], desc[2], desc[3]); 505 return (true); 506 } 507 508 static Elf_Brandnote linux64_brandnote = { 509 .hdr.n_namesz = sizeof(GNU_ABI_VENDOR), 510 .hdr.n_descsz = 16, 511 .hdr.n_type = 1, 512 .vendor = GNU_ABI_VENDOR, 513 .flags = BN_TRANSLATE_OSREL, 514 .trans_osrel = linux_trans_osrel 515 }; 516 517 static Elf64_Brandinfo linux_glibc2brand = { 518 .brand = ELFOSABI_LINUX, 519 .machine = EM_AARCH64, 520 .compat_3_brand = "Linux", 521 .emul_path = linux_emul_path, 522 .interp_path = "/lib64/ld-linux-x86-64.so.2", 523 .sysvec = &elf_linux_sysvec, 524 .interp_newpath = NULL, 525 .brand_note = &linux64_brandnote, 526 .flags = BI_CAN_EXEC_DYN | BI_BRAND_NOTE 527 }; 528 529 Elf64_Brandinfo *linux_brandlist[] = { 530 &linux_glibc2brand, 531 NULL 532 }; 533 534 static int 535 linux64_elf_modevent(module_t mod, int type, void *data) 536 { 537 Elf64_Brandinfo **brandinfo; 538 struct linux_ioctl_handler**lihp; 539 int error; 540 541 error = 0; 542 switch(type) { 543 case MOD_LOAD: 544 for (brandinfo = &linux_brandlist[0]; *brandinfo != NULL; 545 ++brandinfo) 546 if (elf64_insert_brand_entry(*brandinfo) < 0) 547 error = EINVAL; 548 if (error == 0) { 549 SET_FOREACH(lihp, linux_ioctl_handler_set) 550 linux_ioctl_register_handler(*lihp); 551 stclohz = (stathz ? stathz : hz); 552 if (bootverbose) 553 printf("Linux arm64 ELF exec handler installed\n"); 554 } 555 break; 556 case MOD_UNLOAD: 557 for (brandinfo = &linux_brandlist[0]; *brandinfo != NULL; 558 ++brandinfo) 559 if (elf64_brand_inuse(*brandinfo)) 560 error = EBUSY; 561 if (error == 0) { 562 for (brandinfo = &linux_brandlist[0]; 563 *brandinfo != NULL; ++brandinfo) 564 if (elf64_remove_brand_entry(*brandinfo) < 0) 565 error = EINVAL; 566 } 567 if (error == 0) { 568 SET_FOREACH(lihp, linux_ioctl_handler_set) 569 linux_ioctl_unregister_handler(*lihp); 570 if (bootverbose) 571 printf("Linux ELF exec handler removed\n"); 572 } else 573 printf("Could not deinstall ELF interpreter entry\n"); 574 break; 575 default: 576 return (EOPNOTSUPP); 577 } 578 return (error); 579 } 580 581 static moduledata_t linux64_elf_mod = { 582 "linux64elf", 583 linux64_elf_modevent, 584 0 585 }; 586 587 DECLARE_MODULE_TIED(linux64elf, linux64_elf_mod, SI_SUB_EXEC, SI_ORDER_ANY); 588 MODULE_DEPEND(linux64elf, linux_common, 1, 1, 1); 589 FEATURE(linux64, "AArch64 Linux 64bit support"); 590