linux_machdep.c revision 1.9
1 /* $NetBSD: linux_machdep.c,v 1.9 2005/06/24 22:57:05 manu Exp $ */ 2 3 /*- 4 * Copyright (c) 2005 Emmanuel Dreyfus, all rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 3. All advertising materials mentioning features or use of this software 15 * must display the following acknowledgement: 16 * This product includes software developed by Emmanuel Dreyfus 17 * 4. The name of the author may not be used to endorse or promote 18 * products derived from this software without specific prior written 19 * permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE THE AUTHOR AND CONTRIBUTORS ``AS IS'' 22 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, 23 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 24 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS 25 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 26 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 27 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 28 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 29 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 30 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 31 * POSSIBILITY OF SUCH DAMAGE. 32 */ 33 34 #include <sys/cdefs.h> 35 36 __KERNEL_RCSID(0, "$NetBSD: linux_machdep.c,v 1.9 2005/06/24 22:57:05 manu Exp $"); 37 38 #include <sys/param.h> 39 #include <sys/types.h> 40 #include <sys/systm.h> 41 #include <sys/signal.h> 42 #include <sys/exec.h> 43 #include <sys/proc.h> 44 #include <sys/ptrace.h> /* for process_read_fpregs() */ 45 #include <sys/user.h> 46 #include <sys/ucontext.h> 47 48 #include <machine/reg.h> 49 #include <machine/pcb.h> 50 #include <machine/fpu.h> 51 #include <machine/mcontext.h> 52 #include <machine/specialreg.h> 53 #include <machine/vmparam.h> 54 55 #include <compat/linux/common/linux_signal.h> 56 #include <compat/linux/common/linux_errno.h> 57 #include <compat/linux/common/linux_exec.h> 58 #include <compat/linux/common/linux_ioctl.h> 59 #include <compat/linux/common/linux_prctl.h> 60 #include <compat/linux/common/linux_machdep.h> 61 #include <compat/linux/linux_syscall.h> 62 #include <compat/linux/linux_syscallargs.h> 63 64 static void linux_buildcontext(struct lwp *, void *, void *); 65 66 void 67 linux_setregs(l, epp, stack) 68 struct lwp *l; 69 struct exec_package *epp; 70 u_long stack; 71 { 72 struct pcb *pcb = &l->l_addr->u_pcb; 73 struct trapframe *tf; 74 75 /* If we were using the FPU, forget about it. */ 76 if (l->l_addr->u_pcb.pcb_fpcpu != NULL) 77 fpusave_lwp(l, 0); 78 79 l->l_md.md_flags &= ~MDP_USEDFPU; 80 pcb->pcb_flags = 0; 81 pcb->pcb_savefpu.fp_fxsave.fx_fcw = __NetBSD_NPXCW__; 82 pcb->pcb_savefpu.fp_fxsave.fx_mxcsr = __INITIAL_MXCSR__; 83 pcb->pcb_savefpu.fp_fxsave.fx_mxcsr_mask = __INITIAL_MXCSR_MASK__; 84 pcb->pcb_fs = 0; 85 pcb->pcb_gs = 0; 86 87 l->l_proc->p_flag &= ~P_32; 88 89 tf = l->l_md.md_regs; 90 tf->tf_rax = 0; 91 tf->tf_rbx = 0; 92 tf->tf_rcx = epp->ep_entry; 93 tf->tf_rdx = 0; 94 tf->tf_rsi = 0; 95 tf->tf_rdi = 0; 96 tf->tf_rbp = 0; 97 tf->tf_rsp = stack; 98 tf->tf_r8 = 0; 99 tf->tf_r9 = 0; 100 tf->tf_r10 = 0; 101 tf->tf_r11 = 0; 102 tf->tf_r12 = 0; 103 tf->tf_r13 = 0; 104 tf->tf_r14 = 0; 105 tf->tf_r15 = 0; 106 tf->tf_rip = epp->ep_entry; 107 tf->tf_rflags = PSL_USERSET; 108 tf->tf_cs = GSEL(GUCODE_SEL, SEL_UPL); 109 tf->tf_ss = GSEL(GUDATA_SEL, SEL_UPL); 110 tf->tf_ds = 0; 111 tf->tf_es = 0; 112 tf->tf_fs = 0; 113 tf->tf_gs = 0; 114 115 return; 116 } 117 118 void 119 linux_sendsig(ksi, mask) 120 const ksiginfo_t *ksi; 121 const sigset_t *mask; 122 { 123 struct lwp *l = curlwp; 124 struct proc *p = l->l_proc; 125 struct sigacts *ps = p->p_sigacts; 126 int onstack; 127 int sig = ksi->ksi_signo; 128 struct linux_rt_sigframe *sfp, sigframe; 129 struct linux__fpstate *fpsp, fpstate; 130 struct fpreg fpregs; 131 struct trapframe *tf = l->l_md.md_regs; 132 sig_t catcher = SIGACTION(p, sig).sa_handler; 133 linux_sigset_t lmask; 134 char *sp; 135 int error; 136 137 /* Do we need to jump onto the signal stack? */ 138 onstack = 139 (p->p_sigctx.ps_sigstk.ss_flags & (SS_DISABLE | SS_ONSTACK)) == 0 && 140 (SIGACTION(p, sig).sa_flags & SA_ONSTACK) != 0; 141 142 /* Allocate space for the signal handler context. */ 143 if (onstack) 144 sp = ((caddr_t)p->p_sigctx.ps_sigstk.ss_sp + 145 p->p_sigctx.ps_sigstk.ss_size); 146 else 147 sp = (caddr_t)tf->tf_rsp - 128; 148 149 150 /* 151 * Save FPU state, if any 152 */ 153 if (l->l_md.md_flags & MDP_USEDFPU) { 154 sp = (char *) 155 (((long)sp - sizeof(struct linux__fpstate)) & ~0xfUL); 156 fpsp = (struct linux__fpstate *)sp; 157 158 (void)process_read_fpregs(l, &fpregs); 159 bzero(&fpstate, sizeof(fpstate)); 160 161 fpstate.cwd = fpregs.fp_fcw; 162 fpstate.swd = fpregs.fp_fsw; 163 fpstate.twd = fpregs.fp_ftw; 164 fpstate.fop = fpregs.fp_fop; 165 fpstate.rip = fpregs.fp_rip; 166 fpstate.rdp = fpregs.fp_rdp; 167 fpstate.mxcsr = fpregs.fp_mxcsr; 168 fpstate.mxcsr_mask = fpregs.fp_mxcsr_mask; 169 memcpy(&fpstate.st_space, &fpregs.fp_st, 170 sizeof(fpstate.st_space)); 171 memcpy(&fpstate.xmm_space, &fpregs.fp_xmm, 172 sizeof(fpstate.xmm_space)); 173 174 if ((error = copyout(&fpstate, fpsp, sizeof(fpstate))) != 0) { 175 sigexit(l, SIGILL); 176 return; 177 } 178 } else { 179 fpsp = NULL; 180 } 181 182 /* 183 * Populate the rt_sigframe 184 */ 185 sp = (char *) 186 ((((long)sp - sizeof(struct linux_rt_sigframe)) & ~0xfUL) - 8); 187 sfp = (struct linux_rt_sigframe *)sp; 188 189 bzero(&sigframe, sizeof(sigframe)); 190 if (ps->sa_sigdesc[sig].sd_vers != 0) 191 sigframe.pretcode = 192 (char *)(u_long)ps->sa_sigdesc[sig].sd_tramp; 193 else 194 sigframe.pretcode = NULL; 195 196 /* 197 * The user context 198 */ 199 sigframe.uc.luc_flags = 0; 200 sigframe.uc.luc_link = NULL; 201 202 /* This is used regardless of SA_ONSTACK in Linux */ 203 sigframe.uc.luc_stack.ss_sp = p->p_sigctx.ps_sigstk.ss_sp; 204 sigframe.uc.luc_stack.ss_size = p->p_sigctx.ps_sigstk.ss_size; 205 sigframe.uc.luc_stack.ss_flags = 0; 206 if (p->p_sigctx.ps_sigstk.ss_flags & SS_ONSTACK) 207 sigframe.uc.luc_stack.ss_flags |= LINUX_SS_ONSTACK; 208 if (p->p_sigctx.ps_sigstk.ss_flags & SS_DISABLE) 209 sigframe.uc.luc_stack.ss_flags |= LINUX_SS_DISABLE; 210 211 sigframe.uc.luc_mcontext.r8 = tf->tf_r8; 212 sigframe.uc.luc_mcontext.r9 = tf->tf_r9; 213 sigframe.uc.luc_mcontext.r10 = tf->tf_r10; 214 sigframe.uc.luc_mcontext.r11 = tf->tf_r11; 215 sigframe.uc.luc_mcontext.r12 = tf->tf_r12; 216 sigframe.uc.luc_mcontext.r13 = tf->tf_r13; 217 sigframe.uc.luc_mcontext.r14 = tf->tf_r14; 218 sigframe.uc.luc_mcontext.r15 = tf->tf_r15; 219 sigframe.uc.luc_mcontext.rdi = tf->tf_rdi; 220 sigframe.uc.luc_mcontext.rsi = tf->tf_rsi; 221 sigframe.uc.luc_mcontext.rbp = tf->tf_rbp; 222 sigframe.uc.luc_mcontext.rbx = tf->tf_rbx; 223 sigframe.uc.luc_mcontext.rdx = tf->tf_rdx; 224 sigframe.uc.luc_mcontext.rcx = tf->tf_rcx; 225 sigframe.uc.luc_mcontext.rsp = tf->tf_rsp; 226 sigframe.uc.luc_mcontext.rip = tf->tf_rip; 227 sigframe.uc.luc_mcontext.eflags = tf->tf_rflags; 228 sigframe.uc.luc_mcontext.cs = tf->tf_cs; 229 sigframe.uc.luc_mcontext.gs = tf->tf_gs; 230 sigframe.uc.luc_mcontext.fs = tf->tf_fs; 231 sigframe.uc.luc_mcontext.err = tf->tf_err; 232 sigframe.uc.luc_mcontext.trapno = tf->tf_trapno; 233 native_to_linux_sigset(&lmask, mask); 234 sigframe.uc.luc_mcontext.oldmask = lmask.sig[0]; 235 sigframe.uc.luc_mcontext.cr2 = (long)l->l_addr->u_pcb.pcb_onfault; 236 sigframe.uc.luc_mcontext.fpstate = fpsp; 237 native_to_linux_sigset(&sigframe.uc.luc_sigmask, mask); 238 239 /* 240 * the siginfo structure 241 */ 242 sigframe.info.lsi_signo = native_to_linux_signo[sig]; 243 sigframe.info.lsi_errno = native_to_linux_errno[ksi->ksi_errno]; 244 sigframe.info.lsi_code = ksi->ksi_code; 245 246 /* XXX This is a rought conversion, taken from i386 code */ 247 switch (sigframe.info.lsi_signo) { 248 case LINUX_SIGILL: 249 case LINUX_SIGFPE: 250 case LINUX_SIGSEGV: 251 case LINUX_SIGBUS: 252 case LINUX_SIGTRAP: 253 sigframe.info._sifields._sigfault._addr = ksi->ksi_addr; 254 break; 255 case LINUX_SIGCHLD: 256 sigframe.info._sifields._sigchld._pid = ksi->ksi_pid; 257 sigframe.info._sifields._sigchld._uid = ksi->ksi_uid; 258 sigframe.info._sifields._sigchld._utime = ksi->ksi_utime; 259 sigframe.info._sifields._sigchld._stime = ksi->ksi_stime; 260 261 if (WCOREDUMP(ksi->ksi_status)) { 262 sigframe.info.lsi_code = LINUX_CLD_DUMPED; 263 sigframe.info._sifields._sigchld._status = 264 _WSTATUS(ksi->ksi_status); 265 } else if (_WSTATUS(ksi->ksi_status)) { 266 sigframe.info.lsi_code = LINUX_CLD_KILLED; 267 sigframe.info._sifields._sigchld._status = 268 _WSTATUS(ksi->ksi_status); 269 } else { 270 sigframe.info.lsi_code = LINUX_CLD_EXITED; 271 sigframe.info._sifields._sigchld._status = 272 ((ksi->ksi_status & 0xff00U) >> 8); 273 } 274 break; 275 case LINUX_SIGIO: 276 sigframe.info._sifields._sigpoll._band = ksi->ksi_band; 277 sigframe.info._sifields._sigpoll._fd = ksi->ksi_fd; 278 break; 279 default: 280 sigframe.info._sifields._sigchld._pid = ksi->ksi_pid; 281 sigframe.info._sifields._sigchld._uid = ksi->ksi_uid; 282 if ((sigframe.info.lsi_signo == LINUX_SIGALRM) || 283 (sigframe.info.lsi_signo >= LINUX_SIGRTMIN)) 284 sigframe.info._sifields._timer._sigval.sival_ptr = 285 ksi->ksi_sigval.sival_ptr; 286 break; 287 } 288 289 if ((error = copyout(&sigframe, sp, sizeof(sigframe))) != 0) { 290 sigexit(l, SIGILL); 291 return; 292 } 293 294 linux_buildcontext(l, catcher, sp); 295 tf->tf_rdi = sigframe.info.lsi_signo; 296 tf->tf_rax = 0; 297 tf->tf_rsi = (long)&sfp->info; 298 tf->tf_rdx = (long)&sfp->uc; 299 300 /* 301 * Remember we use signal stack 302 */ 303 if (onstack) 304 p->p_sigctx.ps_sigstk.ss_flags |= SS_ONSTACK; 305 return; 306 } 307 308 int 309 linux_sys_modify_ldt(l, v, retval) 310 struct lwp *l; 311 void *v; 312 register_t *retval; 313 { 314 return 0; 315 } 316 317 int 318 linux_sys_iopl(l, v, retval) 319 struct lwp *l; 320 void *v; 321 register_t *retval; 322 { 323 return 0; 324 } 325 326 int 327 linux_sys_ioperm(l, v, retval) 328 struct lwp *l; 329 void *v; 330 register_t *retval; 331 { 332 return 0; 333 } 334 335 dev_t 336 linux_fakedev(dev, raw) 337 dev_t dev; 338 int raw; 339 { 340 return 0; 341 } 342 343 int 344 linux_machdepioctl(p, v, retval) 345 struct proc *p; 346 void *v; 347 register_t *retval; 348 { 349 return 0; 350 } 351 352 int 353 linux_sys_rt_sigreturn(l, v, retval) 354 struct lwp *l; 355 void *v; 356 register_t *retval; 357 { 358 struct linux_ucontext *luctx; 359 struct trapframe *tf = l->l_md.md_regs; 360 struct linux_sigcontext *lsigctx; 361 struct linux__fpstate fpstate; 362 struct linux_rt_sigframe frame, *fp; 363 ucontext_t uctx; 364 mcontext_t *mctx; 365 struct fxsave64 *fxsave; 366 int error; 367 368 fp = (struct linux_rt_sigframe *)(tf->tf_rsp - 8); 369 if ((error = copyin(fp, &frame, sizeof(frame))) != 0) { 370 sigexit(l, SIGILL); 371 return error; 372 } 373 luctx = &frame.uc; 374 lsigctx = &luctx->luc_mcontext; 375 376 bzero(&uctx, sizeof(uctx)); 377 mctx = (mcontext_t *)&uctx.uc_mcontext; 378 fxsave = (struct fxsave64 *)&mctx->__fpregs; 379 380 /* 381 * Set the flags. Linux always have CPU, stack and signal state, 382 * FPU is optional. uc_flags is not used to tell what we have. 383 */ 384 uctx.uc_flags = (_UC_SIGMASK|_UC_CPU|_UC_STACK|_UC_CLRSTACK); 385 if (lsigctx->fpstate != NULL) 386 uctx.uc_flags |= _UC_FPU; 387 uctx.uc_link = NULL; 388 389 /* 390 * Signal set 391 */ 392 linux_to_native_sigset(&uctx.uc_sigmask, &luctx->luc_sigmask); 393 394 /* 395 * CPU state 396 */ 397 mctx->__gregs[_REG_R8] = lsigctx->r8; 398 mctx->__gregs[_REG_R9] = lsigctx->r9; 399 mctx->__gregs[_REG_R10] = lsigctx->r10; 400 mctx->__gregs[_REG_R11] = lsigctx->r11; 401 mctx->__gregs[_REG_R12] = lsigctx->r12; 402 mctx->__gregs[_REG_R13] = lsigctx->r13; 403 mctx->__gregs[_REG_R14] = lsigctx->r14; 404 mctx->__gregs[_REG_R15] = lsigctx->r15; 405 mctx->__gregs[_REG_RDI] = lsigctx->rdi; 406 mctx->__gregs[_REG_RSI] = lsigctx->rsi; 407 mctx->__gregs[_REG_RBP] = lsigctx->rbp; 408 mctx->__gregs[_REG_RBX] = lsigctx->rbx; 409 mctx->__gregs[_REG_RAX] = tf->tf_rax; 410 mctx->__gregs[_REG_RDX] = lsigctx->rdx; 411 mctx->__gregs[_REG_RCX] = lsigctx->rcx; 412 mctx->__gregs[_REG_RIP] = lsigctx->rip; 413 mctx->__gregs[_REG_RFL] = lsigctx->eflags; 414 mctx->__gregs[_REG_CS] = lsigctx->cs; 415 mctx->__gregs[_REG_GS] = lsigctx->gs; 416 mctx->__gregs[_REG_FS] = lsigctx->fs; 417 mctx->__gregs[_REG_ERR] = lsigctx->err; 418 mctx->__gregs[_REG_TRAPNO] = lsigctx->trapno; 419 mctx->__gregs[_REG_ES] = tf->tf_es; 420 mctx->__gregs[_REG_DS] = tf->tf_ds; 421 mctx->__gregs[_REG_URSP] = lsigctx->rsp; /* XXX */ 422 mctx->__gregs[_REG_SS] = tf->tf_ss; 423 424 /* 425 * FPU state 426 */ 427 if (lsigctx->fpstate != NULL) { 428 error = copyin(lsigctx->fpstate, &fpstate, sizeof(fpstate)); 429 if (error != 0) { 430 sigexit(l, SIGILL); 431 return error; 432 } 433 434 fxsave->fx_fcw = fpstate.cwd; 435 fxsave->fx_fsw = fpstate.swd; 436 fxsave->fx_ftw = fpstate.twd; 437 fxsave->fx_fop = fpstate.fop; 438 fxsave->fx_rip = fpstate.rip; 439 fxsave->fx_rdp = fpstate.rdp; 440 fxsave->fx_mxcsr = fpstate.mxcsr; 441 fxsave->fx_mxcsr_mask = fpstate.mxcsr_mask; 442 memcpy(&fxsave->fx_st, &fpstate.st_space, 443 sizeof(fxsave->fx_st)); 444 memcpy(&fxsave->fx_xmm, &fpstate.xmm_space, 445 sizeof(fxsave->fx_xmm)); 446 } 447 448 /* 449 * And the stack 450 */ 451 uctx.uc_stack.ss_flags = 0; 452 if (luctx->luc_stack.ss_flags & LINUX_SS_ONSTACK); 453 uctx.uc_stack.ss_flags = SS_ONSTACK; 454 455 if (luctx->luc_stack.ss_flags & LINUX_SS_DISABLE); 456 uctx.uc_stack.ss_flags = SS_DISABLE; 457 458 uctx.uc_stack.ss_sp = luctx->luc_stack.ss_sp; 459 uctx.uc_stack.ss_size = luctx->luc_stack.ss_size; 460 461 /* 462 * And let setucontext deal with that. 463 */ 464 return setucontext(l, &uctx); 465 } 466 467 int 468 linux_sys_arch_prctl(l, v, retval) 469 struct lwp *l; 470 void *v; 471 register_t *retval; 472 { 473 struct linux_sys_arch_prctl_args /* { 474 syscallarg(int) code; 475 syscallarg(unsigned long) addr; 476 } */ *uap = v; 477 struct pcb *pcb = &l->l_addr->u_pcb; 478 struct trapframe *tf = l->l_md.md_regs; 479 int error; 480 uint64_t taddr; 481 482 switch(SCARG(uap, code)) { 483 case LINUX_ARCH_SET_GS: 484 taddr = SCARG(uap, addr); 485 if (taddr >= VM_MAXUSER_ADDRESS) 486 return EINVAL; 487 pcb->pcb_gs = taddr; 488 pcb->pcb_flags |= PCB_GS64; 489 if (l == curlwp) 490 wrmsr(MSR_KERNELGSBASE, taddr); 491 break; 492 493 case LINUX_ARCH_GET_GS: 494 if (pcb->pcb_flags & PCB_GS64) 495 taddr = pcb->pcb_gs; 496 else { 497 error = memseg_baseaddr(l, tf->tf_fs, NULL, 0, &taddr); 498 if (error != 0) 499 return error; 500 } 501 error = copyout(&taddr, (char *)SCARG(uap, addr), 8); 502 if (error != 0) 503 return error; 504 break; 505 506 case LINUX_ARCH_SET_FS: 507 taddr = SCARG(uap, addr); 508 if (taddr >= VM_MAXUSER_ADDRESS) 509 return EINVAL; 510 pcb->pcb_fs = taddr; 511 pcb->pcb_flags |= PCB_FS64; 512 if (l == curlwp) 513 wrmsr(MSR_FSBASE, taddr); 514 break; 515 516 case LINUX_ARCH_GET_FS: 517 if (pcb->pcb_flags & PCB_FS64) 518 taddr = pcb->pcb_fs; 519 else { 520 error = memseg_baseaddr(l, tf->tf_fs, NULL, 0, &taddr); 521 if (error != 0) 522 return error; 523 } 524 error = copyout(&taddr, (char *)SCARG(uap, addr), 8); 525 if (error != 0) 526 return error; 527 break; 528 529 default: 530 #ifdef DEBUG_LINUX 531 printf("linux_sys_arch_prctl: unexpected code %d\n", 532 SCARG(uap, code)); 533 #endif 534 return EINVAL; 535 } 536 537 return 0; 538 } 539 540 const int linux_vsyscall_to_syscall[] = { 541 LINUX_SYS_gettimeofday, 542 LINUX_SYS_time, 543 LINUX_SYS_nosys, 544 LINUX_SYS_nosys, 545 }; 546 547 int 548 linux_usertrap(struct lwp *l, vaddr_t trapaddr, void *arg) 549 { 550 struct trapframe *tf = arg; 551 uint64_t retaddr; 552 int vsyscallnr; 553 554 /* 555 * Check for a vsyscall. %rip must be the fault address, 556 * and the address must be in the Linux vsyscall area. 557 * Also, vsyscalls are only done at 1024-byte boundaries. 558 */ 559 560 if (__predict_true(trapaddr < LINUX_VSYSCALL_START)) 561 return 0; 562 563 if (trapaddr != tf->tf_rip) 564 return 0; 565 566 if ((tf->tf_rip & (LINUX_VSYSCALL_SIZE - 1)) != 0) 567 return 0; 568 569 vsyscallnr = (tf->tf_rip - LINUX_VSYSCALL_START) / LINUX_VSYSCALL_SIZE; 570 571 if (vsyscallnr > LINUX_VSYSCALL_MAXNR) 572 return 0; 573 574 /* 575 * Get the return address from the top of the stack, 576 * and fix up the return address. 577 * This assumes the faulting instruction was callq *reg, 578 * which is the only way that vsyscalls are ever entered. 579 */ 580 if (copyin((void *)tf->tf_rsp, &retaddr, sizeof retaddr) != 0) 581 return 0; 582 tf->tf_rip = retaddr; 583 tf->tf_rax = linux_vsyscall_to_syscall[vsyscallnr]; 584 tf->tf_rsp += 8; /* "pop" the return address */ 585 586 #if 0 587 printf("usertrap: rip %p rsp %p retaddr %p vsys %d sys %d\n", 588 (void *)tf->tf_rip, (void *)tf->tf_rsp, (void *)retaddr, 589 vsyscallnr, (int)tf->tf_rax); 590 #endif 591 592 (*l->l_proc->p_md.md_syscall)(tf); 593 594 return 1; 595 } 596 597 static void 598 linux_buildcontext(struct lwp *l, void *catcher, void *f) 599 { 600 struct trapframe *tf = l->l_md.md_regs; 601 602 tf->tf_ds = GSEL(GUDATA_SEL, SEL_UPL); 603 tf->tf_rip = (u_int64_t)catcher; 604 tf->tf_cs = GSEL(GUCODE_SEL, SEL_UPL); 605 tf->tf_rflags &= ~(PSL_T|PSL_VM|PSL_AC); 606 tf->tf_rsp = (u_int64_t)f; 607 tf->tf_ss = GSEL(GUDATA_SEL, SEL_UPL); 608 } 609
Indexes created Tue Sep 30 20:09:53 GMT 2025