2 * SPDX-License-Identifier: BSD-4-Clause
4 * Copyright (c) 2018 The FreeBSD Foundation
5 * Copyright (c) 1992 Terrence R. Lambert.
6 * Copyright (c) 1982, 1987, 1990 The Regents of the University of California.
9 * This code is derived from software contributed to Berkeley by
12 * Portions of this software were developed by A. Joseph Koshy under
13 * sponsorship from the FreeBSD Foundation and Google, Inc.
15 * Redistribution and use in source and binary forms, with or without
16 * modification, are permitted provided that the following conditions
18 * 1. Redistributions of source code must retain the above copyright
19 * notice, this list of conditions and the following disclaimer.
20 * 2. Redistributions in binary form must reproduce the above copyright
21 * notice, this list of conditions and the following disclaimer in the
22 * documentation and/or other materials provided with the distribution.
23 * 3. All advertising materials mentioning features or use of this software
24 * must display the following acknowledgement:
25 * This product includes software developed by the University of
26 * California, Berkeley and its contributors.
27 * 4. Neither the name of the University nor the names of its contributors
28 * may be used to endorse or promote products derived from this software
29 * without specific prior written permission.
31 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
32 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
33 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
34 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
35 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
36 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
37 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
38 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
39 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
40 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
43 * from: @(#)machdep.c 7.4 (Berkeley) 6/3/91
46 #include <sys/cdefs.h>
47 __FBSDID("$FreeBSD$");
51 #include "opt_kstack_pages.h"
53 #include <sys/param.h>
55 #include <sys/systm.h>
57 #include <sys/imgact.h>
59 #include <sys/kernel.h>
61 #include <sys/linker.h>
63 #include <sys/malloc.h>
64 #include <sys/mutex.h>
66 #include <sys/ptrace.h>
68 #include <sys/rwlock.h>
69 #include <sys/signalvar.h>
70 #include <sys/syscallsubr.h>
71 #include <sys/sysctl.h>
72 #include <sys/sysent.h>
73 #include <sys/sysproto.h>
74 #include <sys/ucontext.h>
75 #include <sys/vmmeter.h>
78 #include <vm/vm_param.h>
79 #include <vm/vm_extern.h>
80 #include <vm/vm_kern.h>
81 #include <vm/vm_page.h>
82 #include <vm/vm_map.h>
83 #include <vm/vm_object.h>
87 #error KDB must be enabled in order for DDB to work!
90 #include <ddb/db_sym.h>
93 #include <machine/cpu.h>
94 #include <machine/cputypes.h>
95 #include <machine/md_var.h>
96 #include <machine/pcb.h>
97 #include <machine/pcb_ext.h>
98 #include <machine/proc.h>
99 #include <machine/sigframe.h>
100 #include <machine/specialreg.h>
101 #include <machine/sysarch.h>
102 #include <machine/trap.h>
104 static void fpstate_drop(struct thread *td);
105 static void get_fpcontext(struct thread *td, mcontext_t *mcp,
106 char *xfpusave, size_t xfpusave_len);
107 static int set_fpcontext(struct thread *td, mcontext_t *mcp,
108 char *xfpustate, size_t xfpustate_len);
110 static void osendsig(sig_t catcher, ksiginfo_t *, sigset_t *mask);
112 #ifdef COMPAT_FREEBSD4
113 static void freebsd4_sendsig(sig_t catcher, ksiginfo_t *, sigset_t *mask);
116 extern struct sysentvec elf32_freebsd_sysvec;
118 _Static_assert(sizeof(mcontext_t) == 640, "mcontext_t size incorrect");
119 _Static_assert(sizeof(ucontext_t) == 704, "ucontext_t size incorrect");
120 _Static_assert(sizeof(siginfo_t) == 64, "siginfo_t size incorrect");
123 * Send an interrupt to process.
125 * Stack is set up to allow sigcode stored at top to call routine,
126 * followed by call to sigreturn routine below. After sigreturn
127 * resets the signal mask, the stack, and the frame pointer, it
128 * returns to the user specified pc, psl.
132 osendsig(sig_t catcher, ksiginfo_t *ksi, sigset_t *mask)
134 struct osigframe sf, *fp;
138 struct trapframe *regs;
144 PROC_LOCK_ASSERT(p, MA_OWNED);
145 sig = ksi->ksi_signo;
147 mtx_assert(&psp->ps_mtx, MA_OWNED);
149 oonstack = sigonstack(regs->tf_esp);
151 /* Allocate space for the signal handler context. */
152 if ((td->td_pflags & TDP_ALTSTACK) && !oonstack &&
153 SIGISMEMBER(psp->ps_sigonstack, sig)) {
154 fp = (struct osigframe *)((uintptr_t)td->td_sigstk.ss_sp +
155 td->td_sigstk.ss_size - sizeof(struct osigframe));
156 #if defined(COMPAT_43)
157 td->td_sigstk.ss_flags |= SS_ONSTACK;
160 fp = (struct osigframe *)regs->tf_esp - 1;
162 /* Build the argument list for the signal handler. */
164 sf.sf_scp = (register_t)&fp->sf_siginfo.si_sc;
165 bzero(&sf.sf_siginfo, sizeof(sf.sf_siginfo));
166 if (SIGISMEMBER(psp->ps_siginfo, sig)) {
167 /* Signal handler installed with SA_SIGINFO. */
168 sf.sf_arg2 = (register_t)&fp->sf_siginfo;
169 sf.sf_siginfo.si_signo = sig;
170 sf.sf_siginfo.si_code = ksi->ksi_code;
171 sf.sf_ahu.sf_action = (__osiginfohandler_t *)catcher;
174 /* Old FreeBSD-style arguments. */
175 sf.sf_arg2 = ksi->ksi_code;
176 sf.sf_addr = (register_t)ksi->ksi_addr;
177 sf.sf_ahu.sf_handler = catcher;
179 mtx_unlock(&psp->ps_mtx);
182 /* Save most if not all of trap frame. */
183 sf.sf_siginfo.si_sc.sc_eax = regs->tf_eax;
184 sf.sf_siginfo.si_sc.sc_ebx = regs->tf_ebx;
185 sf.sf_siginfo.si_sc.sc_ecx = regs->tf_ecx;
186 sf.sf_siginfo.si_sc.sc_edx = regs->tf_edx;
187 sf.sf_siginfo.si_sc.sc_esi = regs->tf_esi;
188 sf.sf_siginfo.si_sc.sc_edi = regs->tf_edi;
189 sf.sf_siginfo.si_sc.sc_cs = regs->tf_cs;
190 sf.sf_siginfo.si_sc.sc_ds = regs->tf_ds;
191 sf.sf_siginfo.si_sc.sc_ss = regs->tf_ss;
192 sf.sf_siginfo.si_sc.sc_es = regs->tf_es;
193 sf.sf_siginfo.si_sc.sc_fs = regs->tf_fs;
194 sf.sf_siginfo.si_sc.sc_gs = rgs();
195 sf.sf_siginfo.si_sc.sc_isp = regs->tf_isp;
197 /* Build the signal context to be used by osigreturn(). */
198 sf.sf_siginfo.si_sc.sc_onstack = (oonstack) ? 1 : 0;
199 SIG2OSIG(*mask, sf.sf_siginfo.si_sc.sc_mask);
200 sf.sf_siginfo.si_sc.sc_sp = regs->tf_esp;
201 sf.sf_siginfo.si_sc.sc_fp = regs->tf_ebp;
202 sf.sf_siginfo.si_sc.sc_pc = regs->tf_eip;
203 sf.sf_siginfo.si_sc.sc_ps = regs->tf_eflags;
204 sf.sf_siginfo.si_sc.sc_trapno = regs->tf_trapno;
205 sf.sf_siginfo.si_sc.sc_err = regs->tf_err;
208 * If we're a vm86 process, we want to save the segment registers.
209 * We also change eflags to be our emulated eflags, not the actual
212 if (regs->tf_eflags & PSL_VM) {
213 /* XXX confusing names: `tf' isn't a trapframe; `regs' is. */
214 struct trapframe_vm86 *tf = (struct trapframe_vm86 *)regs;
215 struct vm86_kernel *vm86 = &td->td_pcb->pcb_ext->ext_vm86;
217 sf.sf_siginfo.si_sc.sc_gs = tf->tf_vm86_gs;
218 sf.sf_siginfo.si_sc.sc_fs = tf->tf_vm86_fs;
219 sf.sf_siginfo.si_sc.sc_es = tf->tf_vm86_es;
220 sf.sf_siginfo.si_sc.sc_ds = tf->tf_vm86_ds;
222 if (vm86->vm86_has_vme == 0)
223 sf.sf_siginfo.si_sc.sc_ps =
224 (tf->tf_eflags & ~(PSL_VIF | PSL_VIP)) |
225 (vm86->vm86_eflags & (PSL_VIF | PSL_VIP));
227 /* See sendsig() for comments. */
228 tf->tf_eflags &= ~(PSL_VM | PSL_NT | PSL_VIF | PSL_VIP);
232 * Copy the sigframe out to the user's stack.
234 if (copyout(&sf, fp, sizeof(*fp)) != 0) {
239 regs->tf_esp = (int)fp;
240 if (p->p_sysent->sv_sigcode_base != 0) {
241 regs->tf_eip = p->p_sysent->sv_sigcode_base + szsigcode -
244 /* a.out sysentvec does not use shared page */
245 regs->tf_eip = PROC_PS_STRINGS(p) - szosigcode;
247 regs->tf_eflags &= ~(PSL_T | PSL_D);
248 regs->tf_cs = _ucodesel;
249 regs->tf_ds = _udatasel;
250 regs->tf_es = _udatasel;
251 regs->tf_fs = _udatasel;
253 regs->tf_ss = _udatasel;
255 mtx_lock(&psp->ps_mtx);
257 #endif /* COMPAT_43 */
259 #ifdef COMPAT_FREEBSD4
261 freebsd4_sendsig(sig_t catcher, ksiginfo_t *ksi, sigset_t *mask)
263 struct freebsd4_sigframe sf, *sfp;
267 struct trapframe *regs;
273 PROC_LOCK_ASSERT(p, MA_OWNED);
274 sig = ksi->ksi_signo;
276 mtx_assert(&psp->ps_mtx, MA_OWNED);
278 oonstack = sigonstack(regs->tf_esp);
280 /* Save user context. */
281 bzero(&sf, sizeof(sf));
282 sf.sf_uc.uc_sigmask = *mask;
283 sf.sf_uc.uc_stack = td->td_sigstk;
284 sf.sf_uc.uc_stack.ss_flags = (td->td_pflags & TDP_ALTSTACK)
285 ? ((oonstack) ? SS_ONSTACK : 0) : SS_DISABLE;
286 sf.sf_uc.uc_mcontext.mc_onstack = (oonstack) ? 1 : 0;
287 sf.sf_uc.uc_mcontext.mc_gs = rgs();
288 bcopy(regs, &sf.sf_uc.uc_mcontext.mc_fs, sizeof(*regs));
289 bzero(sf.sf_uc.uc_mcontext.mc_fpregs,
290 sizeof(sf.sf_uc.uc_mcontext.mc_fpregs));
291 bzero(sf.sf_uc.uc_mcontext.__spare__,
292 sizeof(sf.sf_uc.uc_mcontext.__spare__));
293 bzero(sf.sf_uc.__spare__, sizeof(sf.sf_uc.__spare__));
295 /* Allocate space for the signal handler context. */
296 if ((td->td_pflags & TDP_ALTSTACK) != 0 && !oonstack &&
297 SIGISMEMBER(psp->ps_sigonstack, sig)) {
298 sfp = (struct freebsd4_sigframe *)((uintptr_t)td->td_sigstk.ss_sp +
299 td->td_sigstk.ss_size - sizeof(struct freebsd4_sigframe));
300 #if defined(COMPAT_43)
301 td->td_sigstk.ss_flags |= SS_ONSTACK;
304 sfp = (struct freebsd4_sigframe *)regs->tf_esp - 1;
306 /* Build the argument list for the signal handler. */
308 sf.sf_ucontext = (register_t)&sfp->sf_uc;
309 bzero(&sf.sf_si, sizeof(sf.sf_si));
310 if (SIGISMEMBER(psp->ps_siginfo, sig)) {
311 /* Signal handler installed with SA_SIGINFO. */
312 sf.sf_siginfo = (register_t)&sfp->sf_si;
313 sf.sf_ahu.sf_action = (__siginfohandler_t *)catcher;
315 /* Fill in POSIX parts */
316 sf.sf_si.si_signo = sig;
317 sf.sf_si.si_code = ksi->ksi_code;
318 sf.sf_si.si_addr = ksi->ksi_addr;
320 /* Old FreeBSD-style arguments. */
321 sf.sf_siginfo = ksi->ksi_code;
322 sf.sf_addr = (register_t)ksi->ksi_addr;
323 sf.sf_ahu.sf_handler = catcher;
325 mtx_unlock(&psp->ps_mtx);
329 * If we're a vm86 process, we want to save the segment registers.
330 * We also change eflags to be our emulated eflags, not the actual
333 if (regs->tf_eflags & PSL_VM) {
334 struct trapframe_vm86 *tf = (struct trapframe_vm86 *)regs;
335 struct vm86_kernel *vm86 = &td->td_pcb->pcb_ext->ext_vm86;
337 sf.sf_uc.uc_mcontext.mc_gs = tf->tf_vm86_gs;
338 sf.sf_uc.uc_mcontext.mc_fs = tf->tf_vm86_fs;
339 sf.sf_uc.uc_mcontext.mc_es = tf->tf_vm86_es;
340 sf.sf_uc.uc_mcontext.mc_ds = tf->tf_vm86_ds;
342 if (vm86->vm86_has_vme == 0)
343 sf.sf_uc.uc_mcontext.mc_eflags =
344 (tf->tf_eflags & ~(PSL_VIF | PSL_VIP)) |
345 (vm86->vm86_eflags & (PSL_VIF | PSL_VIP));
348 * Clear PSL_NT to inhibit T_TSSFLT faults on return from
349 * syscalls made by the signal handler. This just avoids
350 * wasting time for our lazy fixup of such faults. PSL_NT
351 * does nothing in vm86 mode, but vm86 programs can set it
352 * almost legitimately in probes for old cpu types.
354 tf->tf_eflags &= ~(PSL_VM | PSL_NT | PSL_VIF | PSL_VIP);
358 * Copy the sigframe out to the user's stack.
360 if (copyout(&sf, sfp, sizeof(*sfp)) != 0) {
365 regs->tf_esp = (int)sfp;
366 regs->tf_eip = p->p_sysent->sv_sigcode_base + szsigcode -
368 regs->tf_eflags &= ~(PSL_T | PSL_D);
369 regs->tf_cs = _ucodesel;
370 regs->tf_ds = _udatasel;
371 regs->tf_es = _udatasel;
372 regs->tf_fs = _udatasel;
373 regs->tf_ss = _udatasel;
375 mtx_lock(&psp->ps_mtx);
377 #endif /* COMPAT_FREEBSD4 */
380 sendsig(sig_t catcher, ksiginfo_t *ksi, sigset_t *mask)
382 struct sigframe sf, *sfp;
387 struct trapframe *regs;
388 struct segment_descriptor *sdp;
396 PROC_LOCK_ASSERT(p, MA_OWNED);
397 sig = ksi->ksi_signo;
399 mtx_assert(&psp->ps_mtx, MA_OWNED);
400 #ifdef COMPAT_FREEBSD4
401 if (SIGISMEMBER(psp->ps_freebsd4, sig)) {
402 freebsd4_sendsig(catcher, ksi, mask);
407 if (SIGISMEMBER(psp->ps_osigset, sig)) {
408 osendsig(catcher, ksi, mask);
413 oonstack = sigonstack(regs->tf_esp);
415 if (cpu_max_ext_state_size > sizeof(union savefpu) && use_xsave) {
416 xfpusave_len = cpu_max_ext_state_size - sizeof(union savefpu);
417 xfpusave = __builtin_alloca(xfpusave_len);
423 /* Save user context. */
424 bzero(&sf, sizeof(sf));
425 sf.sf_uc.uc_sigmask = *mask;
426 sf.sf_uc.uc_stack = td->td_sigstk;
427 sf.sf_uc.uc_stack.ss_flags = (td->td_pflags & TDP_ALTSTACK)
428 ? ((oonstack) ? SS_ONSTACK : 0) : SS_DISABLE;
429 sf.sf_uc.uc_mcontext.mc_onstack = (oonstack) ? 1 : 0;
430 sf.sf_uc.uc_mcontext.mc_gs = rgs();
431 bcopy(regs, &sf.sf_uc.uc_mcontext.mc_fs, sizeof(*regs));
432 sf.sf_uc.uc_mcontext.mc_len = sizeof(sf.sf_uc.uc_mcontext); /* magic */
433 get_fpcontext(td, &sf.sf_uc.uc_mcontext, xfpusave, xfpusave_len);
436 * Unconditionally fill the fsbase and gsbase into the mcontext.
438 sdp = &td->td_pcb->pcb_fsd;
439 sf.sf_uc.uc_mcontext.mc_fsbase = sdp->sd_hibase << 24 |
441 sdp = &td->td_pcb->pcb_gsd;
442 sf.sf_uc.uc_mcontext.mc_gsbase = sdp->sd_hibase << 24 |
444 bzero(sf.sf_uc.uc_mcontext.mc_spare2,
445 sizeof(sf.sf_uc.uc_mcontext.mc_spare2));
447 /* Allocate space for the signal handler context. */
448 if ((td->td_pflags & TDP_ALTSTACK) != 0 && !oonstack &&
449 SIGISMEMBER(psp->ps_sigonstack, sig)) {
450 sp = (char *)td->td_sigstk.ss_sp + td->td_sigstk.ss_size;
451 #if defined(COMPAT_43)
452 td->td_sigstk.ss_flags |= SS_ONSTACK;
455 sp = (char *)regs->tf_esp - 128;
456 if (xfpusave != NULL) {
458 sp = (char *)((unsigned int)sp & ~0x3F);
459 sf.sf_uc.uc_mcontext.mc_xfpustate = (register_t)sp;
461 sp -= sizeof(struct sigframe);
463 /* Align to 16 bytes. */
464 sfp = (struct sigframe *)((unsigned int)sp & ~0xF);
466 /* Build the argument list for the signal handler. */
468 sf.sf_ucontext = (register_t)&sfp->sf_uc;
469 bzero(&sf.sf_si, sizeof(sf.sf_si));
470 if (SIGISMEMBER(psp->ps_siginfo, sig)) {
471 /* Signal handler installed with SA_SIGINFO. */
472 sf.sf_siginfo = (register_t)&sfp->sf_si;
473 sf.sf_ahu.sf_action = (__siginfohandler_t *)catcher;
475 /* Fill in POSIX parts */
476 sf.sf_si = ksi->ksi_info;
477 sf.sf_si.si_signo = sig; /* maybe a translated signal */
479 /* Old FreeBSD-style arguments. */
480 sf.sf_siginfo = ksi->ksi_code;
481 sf.sf_addr = (register_t)ksi->ksi_addr;
482 sf.sf_ahu.sf_handler = catcher;
484 mtx_unlock(&psp->ps_mtx);
488 * If we're a vm86 process, we want to save the segment registers.
489 * We also change eflags to be our emulated eflags, not the actual
492 if (regs->tf_eflags & PSL_VM) {
493 struct trapframe_vm86 *tf = (struct trapframe_vm86 *)regs;
494 struct vm86_kernel *vm86 = &td->td_pcb->pcb_ext->ext_vm86;
496 sf.sf_uc.uc_mcontext.mc_gs = tf->tf_vm86_gs;
497 sf.sf_uc.uc_mcontext.mc_fs = tf->tf_vm86_fs;
498 sf.sf_uc.uc_mcontext.mc_es = tf->tf_vm86_es;
499 sf.sf_uc.uc_mcontext.mc_ds = tf->tf_vm86_ds;
501 if (vm86->vm86_has_vme == 0)
502 sf.sf_uc.uc_mcontext.mc_eflags =
503 (tf->tf_eflags & ~(PSL_VIF | PSL_VIP)) |
504 (vm86->vm86_eflags & (PSL_VIF | PSL_VIP));
507 * Clear PSL_NT to inhibit T_TSSFLT faults on return from
508 * syscalls made by the signal handler. This just avoids
509 * wasting time for our lazy fixup of such faults. PSL_NT
510 * does nothing in vm86 mode, but vm86 programs can set it
511 * almost legitimately in probes for old cpu types.
513 tf->tf_eflags &= ~(PSL_VM | PSL_NT | PSL_VIF | PSL_VIP);
517 * Copy the sigframe out to the user's stack.
519 if (copyout(&sf, sfp, sizeof(*sfp)) != 0 ||
520 (xfpusave != NULL && copyout(xfpusave,
521 (void *)sf.sf_uc.uc_mcontext.mc_xfpustate, xfpusave_len)
527 regs->tf_esp = (int)sfp;
528 regs->tf_eip = p->p_sysent->sv_sigcode_base;
529 if (regs->tf_eip == 0)
530 regs->tf_eip = PROC_PS_STRINGS(p) - szsigcode;
531 regs->tf_eflags &= ~(PSL_T | PSL_D);
532 regs->tf_cs = _ucodesel;
533 regs->tf_ds = _udatasel;
534 regs->tf_es = _udatasel;
535 regs->tf_fs = _udatasel;
536 regs->tf_ss = _udatasel;
538 mtx_lock(&psp->ps_mtx);
542 * System call to cleanup state after a signal has been taken. Reset
543 * signal mask and stack state from context left by sendsig (above).
544 * Return to previous pc and psl as specified by context left by
545 * sendsig. Check carefully to make sure that the user has not
546 * modified the state to gain improper privileges.
550 osigreturn(struct thread *td, struct osigreturn_args *uap)
552 struct osigcontext sc;
553 struct trapframe *regs;
554 struct osigcontext *scp;
559 error = copyin(uap->sigcntxp, &sc, sizeof(sc));
564 if (eflags & PSL_VM) {
565 struct trapframe_vm86 *tf = (struct trapframe_vm86 *)regs;
566 struct vm86_kernel *vm86;
569 * if pcb_ext == 0 or vm86_inited == 0, the user hasn't
570 * set up the vm86 area, and we can't enter vm86 mode.
572 if (td->td_pcb->pcb_ext == 0)
574 vm86 = &td->td_pcb->pcb_ext->ext_vm86;
575 if (vm86->vm86_inited == 0)
578 /* Go back to user mode if both flags are set. */
579 if ((eflags & PSL_VIP) && (eflags & PSL_VIF)) {
580 ksiginfo_init_trap(&ksi);
581 ksi.ksi_signo = SIGBUS;
582 ksi.ksi_code = BUS_OBJERR;
583 ksi.ksi_addr = (void *)regs->tf_eip;
584 trapsignal(td, &ksi);
587 if (vm86->vm86_has_vme) {
588 eflags = (tf->tf_eflags & ~VME_USERCHANGE) |
589 (eflags & VME_USERCHANGE) | PSL_VM;
591 vm86->vm86_eflags = eflags; /* save VIF, VIP */
592 eflags = (tf->tf_eflags & ~VM_USERCHANGE) |
593 (eflags & VM_USERCHANGE) | PSL_VM;
595 tf->tf_vm86_ds = scp->sc_ds;
596 tf->tf_vm86_es = scp->sc_es;
597 tf->tf_vm86_fs = scp->sc_fs;
598 tf->tf_vm86_gs = scp->sc_gs;
599 tf->tf_ds = _udatasel;
600 tf->tf_es = _udatasel;
601 tf->tf_fs = _udatasel;
604 * Don't allow users to change privileged or reserved flags.
606 if (!EFL_SECURE(eflags, regs->tf_eflags)) {
611 * Don't allow users to load a valid privileged %cs. Let the
612 * hardware check for invalid selectors, excess privilege in
613 * other selectors, invalid %eip's and invalid %esp's.
615 if (!CS_SECURE(scp->sc_cs)) {
616 ksiginfo_init_trap(&ksi);
617 ksi.ksi_signo = SIGBUS;
618 ksi.ksi_code = BUS_OBJERR;
619 ksi.ksi_trapno = T_PROTFLT;
620 ksi.ksi_addr = (void *)regs->tf_eip;
621 trapsignal(td, &ksi);
624 regs->tf_ds = scp->sc_ds;
625 regs->tf_es = scp->sc_es;
626 regs->tf_fs = scp->sc_fs;
629 /* Restore remaining registers. */
630 regs->tf_eax = scp->sc_eax;
631 regs->tf_ebx = scp->sc_ebx;
632 regs->tf_ecx = scp->sc_ecx;
633 regs->tf_edx = scp->sc_edx;
634 regs->tf_esi = scp->sc_esi;
635 regs->tf_edi = scp->sc_edi;
636 regs->tf_cs = scp->sc_cs;
637 regs->tf_ss = scp->sc_ss;
638 regs->tf_isp = scp->sc_isp;
639 regs->tf_ebp = scp->sc_fp;
640 regs->tf_esp = scp->sc_sp;
641 regs->tf_eip = scp->sc_pc;
642 regs->tf_eflags = eflags;
644 #if defined(COMPAT_43)
645 if (scp->sc_onstack & 1)
646 td->td_sigstk.ss_flags |= SS_ONSTACK;
648 td->td_sigstk.ss_flags &= ~SS_ONSTACK;
650 kern_sigprocmask(td, SIG_SETMASK, (sigset_t *)&scp->sc_mask, NULL,
652 return (EJUSTRETURN);
654 #endif /* COMPAT_43 */
656 #ifdef COMPAT_FREEBSD4
658 freebsd4_sigreturn(struct thread *td, struct freebsd4_sigreturn_args *uap)
660 struct freebsd4_ucontext uc;
661 struct trapframe *regs;
662 struct freebsd4_ucontext *ucp;
663 int cs, eflags, error;
666 error = copyin(uap->sigcntxp, &uc, sizeof(uc));
671 eflags = ucp->uc_mcontext.mc_eflags;
672 if (eflags & PSL_VM) {
673 struct trapframe_vm86 *tf = (struct trapframe_vm86 *)regs;
674 struct vm86_kernel *vm86;
677 * if pcb_ext == 0 or vm86_inited == 0, the user hasn't
678 * set up the vm86 area, and we can't enter vm86 mode.
680 if (td->td_pcb->pcb_ext == 0)
682 vm86 = &td->td_pcb->pcb_ext->ext_vm86;
683 if (vm86->vm86_inited == 0)
686 /* Go back to user mode if both flags are set. */
687 if ((eflags & PSL_VIP) && (eflags & PSL_VIF)) {
688 ksiginfo_init_trap(&ksi);
689 ksi.ksi_signo = SIGBUS;
690 ksi.ksi_code = BUS_OBJERR;
691 ksi.ksi_addr = (void *)regs->tf_eip;
692 trapsignal(td, &ksi);
694 if (vm86->vm86_has_vme) {
695 eflags = (tf->tf_eflags & ~VME_USERCHANGE) |
696 (eflags & VME_USERCHANGE) | PSL_VM;
698 vm86->vm86_eflags = eflags; /* save VIF, VIP */
699 eflags = (tf->tf_eflags & ~VM_USERCHANGE) |
700 (eflags & VM_USERCHANGE) | PSL_VM;
702 bcopy(&ucp->uc_mcontext.mc_fs, tf, sizeof(struct trapframe));
703 tf->tf_eflags = eflags;
704 tf->tf_vm86_ds = tf->tf_ds;
705 tf->tf_vm86_es = tf->tf_es;
706 tf->tf_vm86_fs = tf->tf_fs;
707 tf->tf_vm86_gs = ucp->uc_mcontext.mc_gs;
708 tf->tf_ds = _udatasel;
709 tf->tf_es = _udatasel;
710 tf->tf_fs = _udatasel;
713 * Don't allow users to change privileged or reserved flags.
715 if (!EFL_SECURE(eflags, regs->tf_eflags)) {
717 "pid %d (%s): freebsd4_sigreturn eflags = 0x%x\n",
718 td->td_proc->p_pid, td->td_name, eflags);
723 * Don't allow users to load a valid privileged %cs. Let the
724 * hardware check for invalid selectors, excess privilege in
725 * other selectors, invalid %eip's and invalid %esp's.
727 cs = ucp->uc_mcontext.mc_cs;
728 if (!CS_SECURE(cs)) {
729 uprintf("pid %d (%s): freebsd4_sigreturn cs = 0x%x\n",
730 td->td_proc->p_pid, td->td_name, cs);
731 ksiginfo_init_trap(&ksi);
732 ksi.ksi_signo = SIGBUS;
733 ksi.ksi_code = BUS_OBJERR;
734 ksi.ksi_trapno = T_PROTFLT;
735 ksi.ksi_addr = (void *)regs->tf_eip;
736 trapsignal(td, &ksi);
740 bcopy(&ucp->uc_mcontext.mc_fs, regs, sizeof(*regs));
743 #if defined(COMPAT_43)
744 if (ucp->uc_mcontext.mc_onstack & 1)
745 td->td_sigstk.ss_flags |= SS_ONSTACK;
747 td->td_sigstk.ss_flags &= ~SS_ONSTACK;
749 kern_sigprocmask(td, SIG_SETMASK, &ucp->uc_sigmask, NULL, 0);
750 return (EJUSTRETURN);
752 #endif /* COMPAT_FREEBSD4 */
755 sys_sigreturn(struct thread *td, struct sigreturn_args *uap)
759 struct trapframe *regs;
762 size_t xfpustate_len;
763 int cs, eflags, error, ret;
768 error = copyin(uap->sigcntxp, &uc, sizeof(uc));
772 if ((ucp->uc_mcontext.mc_flags & ~_MC_FLAG_MASK) != 0) {
773 uprintf("pid %d (%s): sigreturn mc_flags %x\n", p->p_pid,
774 td->td_name, ucp->uc_mcontext.mc_flags);
778 eflags = ucp->uc_mcontext.mc_eflags;
779 if (eflags & PSL_VM) {
780 struct trapframe_vm86 *tf = (struct trapframe_vm86 *)regs;
781 struct vm86_kernel *vm86;
784 * if pcb_ext == 0 or vm86_inited == 0, the user hasn't
785 * set up the vm86 area, and we can't enter vm86 mode.
787 if (td->td_pcb->pcb_ext == 0)
789 vm86 = &td->td_pcb->pcb_ext->ext_vm86;
790 if (vm86->vm86_inited == 0)
793 /* Go back to user mode if both flags are set. */
794 if ((eflags & PSL_VIP) && (eflags & PSL_VIF)) {
795 ksiginfo_init_trap(&ksi);
796 ksi.ksi_signo = SIGBUS;
797 ksi.ksi_code = BUS_OBJERR;
798 ksi.ksi_addr = (void *)regs->tf_eip;
799 trapsignal(td, &ksi);
802 if (vm86->vm86_has_vme) {
803 eflags = (tf->tf_eflags & ~VME_USERCHANGE) |
804 (eflags & VME_USERCHANGE) | PSL_VM;
806 vm86->vm86_eflags = eflags; /* save VIF, VIP */
807 eflags = (tf->tf_eflags & ~VM_USERCHANGE) |
808 (eflags & VM_USERCHANGE) | PSL_VM;
810 bcopy(&ucp->uc_mcontext.mc_fs, tf, sizeof(struct trapframe));
811 tf->tf_eflags = eflags;
812 tf->tf_vm86_ds = tf->tf_ds;
813 tf->tf_vm86_es = tf->tf_es;
814 tf->tf_vm86_fs = tf->tf_fs;
815 tf->tf_vm86_gs = ucp->uc_mcontext.mc_gs;
816 tf->tf_ds = _udatasel;
817 tf->tf_es = _udatasel;
818 tf->tf_fs = _udatasel;
821 * Don't allow users to change privileged or reserved flags.
823 if (!EFL_SECURE(eflags, regs->tf_eflags)) {
824 uprintf("pid %d (%s): sigreturn eflags = 0x%x\n",
825 td->td_proc->p_pid, td->td_name, eflags);
830 * Don't allow users to load a valid privileged %cs. Let the
831 * hardware check for invalid selectors, excess privilege in
832 * other selectors, invalid %eip's and invalid %esp's.
834 cs = ucp->uc_mcontext.mc_cs;
835 if (!CS_SECURE(cs)) {
836 uprintf("pid %d (%s): sigreturn cs = 0x%x\n",
837 td->td_proc->p_pid, td->td_name, cs);
838 ksiginfo_init_trap(&ksi);
839 ksi.ksi_signo = SIGBUS;
840 ksi.ksi_code = BUS_OBJERR;
841 ksi.ksi_trapno = T_PROTFLT;
842 ksi.ksi_addr = (void *)regs->tf_eip;
843 trapsignal(td, &ksi);
847 if ((uc.uc_mcontext.mc_flags & _MC_HASFPXSTATE) != 0) {
848 xfpustate_len = uc.uc_mcontext.mc_xfpustate_len;
849 if (xfpustate_len > cpu_max_ext_state_size -
850 sizeof(union savefpu)) {
852 "pid %d (%s): sigreturn xfpusave_len = 0x%zx\n",
853 p->p_pid, td->td_name, xfpustate_len);
856 xfpustate = __builtin_alloca(xfpustate_len);
858 (const void *)uc.uc_mcontext.mc_xfpustate,
859 xfpustate, xfpustate_len);
862 "pid %d (%s): sigreturn copying xfpustate failed\n",
863 p->p_pid, td->td_name);
870 ret = set_fpcontext(td, &ucp->uc_mcontext, xfpustate,
874 bcopy(&ucp->uc_mcontext.mc_fs, regs, sizeof(*regs));
877 #if defined(COMPAT_43)
878 if (ucp->uc_mcontext.mc_onstack & 1)
879 td->td_sigstk.ss_flags |= SS_ONSTACK;
881 td->td_sigstk.ss_flags &= ~SS_ONSTACK;
884 kern_sigprocmask(td, SIG_SETMASK, &ucp->uc_sigmask, NULL, 0);
885 return (EJUSTRETURN);
889 * Reset the hardware debug registers if they were in use.
890 * They won't have any meaning for the newly exec'd process.
893 x86_clear_dbregs(struct pcb *pcb)
895 if ((pcb->pcb_flags & PCB_DBREGS) == 0)
907 * Clear the debug registers on the running CPU,
908 * otherwise they will end up affecting the next
909 * process we switch to.
913 pcb->pcb_flags &= ~PCB_DBREGS;
918 setup_priv_lcall_gate(struct proc *p)
920 struct i386_ldt_args uap;
921 union descriptor desc;
924 bzero(&uap, sizeof(uap));
927 lcall_addr = p->p_sysent->sv_psstrings - sz_lcall_tramp;
928 bzero(&desc, sizeof(desc));
929 desc.sd.sd_type = SDT_MEMERA;
930 desc.sd.sd_dpl = SEL_UPL;
932 desc.sd.sd_def32 = 1;
934 desc.sd.sd_lolimit = 0xffff;
935 desc.sd.sd_hilimit = 0xf;
936 desc.sd.sd_lobase = lcall_addr;
937 desc.sd.sd_hibase = lcall_addr >> 24;
938 i386_set_ldt(curthread, &uap, &desc);
943 * Reset registers to default values on exec.
946 exec_setregs(struct thread *td, struct image_params *imgp, uintptr_t stack)
948 struct trapframe *regs;
950 register_t saved_eflags;
955 /* Reset pc->pcb_gs and %gs before possibly invalidating it. */
956 pcb->pcb_gs = _udatasel;
959 mtx_lock_spin(&dt_lock);
960 if (td->td_proc->p_md.md_ldt != NULL)
963 mtx_unlock_spin(&dt_lock);
966 if (td->td_proc->p_sysent->sv_psstrings !=
967 elf32_freebsd_sysvec.sv_psstrings)
968 setup_priv_lcall_gate(td->td_proc);
972 * Reset the fs and gs bases. The values from the old address
973 * space do not make sense for the new program. In particular,
974 * gsbase might be the TLS base for the old program but the new
975 * program has no TLS now.
980 /* Make sure edx is 0x0 on entry. Linux binaries depend on it. */
981 saved_eflags = regs->tf_eflags & PSL_T;
982 bzero((char *)regs, sizeof(struct trapframe));
983 regs->tf_eip = imgp->entry_addr;
984 regs->tf_esp = stack;
985 regs->tf_eflags = PSL_USER | saved_eflags;
986 regs->tf_ss = _udatasel;
987 regs->tf_ds = _udatasel;
988 regs->tf_es = _udatasel;
989 regs->tf_fs = _udatasel;
990 regs->tf_cs = _ucodesel;
992 /* PS_STRINGS value for BSD/OS binaries. It is 0 for non-BSD/OS. */
993 regs->tf_ebx = (register_t)imgp->ps_strings;
995 x86_clear_dbregs(pcb);
997 pcb->pcb_initial_npxcw = __INITIAL_NPXCW__;
1000 * Drop the FP state if we hold it, so that the process gets a
1001 * clean FP state if it uses the FPU again.
1007 fill_regs(struct thread *td, struct reg *regs)
1010 struct trapframe *tp;
1014 regs->r_gs = pcb->pcb_gs;
1015 return (fill_frame_regs(tp, regs));
1019 fill_frame_regs(struct trapframe *tp, struct reg *regs)
1022 regs->r_fs = tp->tf_fs;
1023 regs->r_es = tp->tf_es;
1024 regs->r_ds = tp->tf_ds;
1025 regs->r_edi = tp->tf_edi;
1026 regs->r_esi = tp->tf_esi;
1027 regs->r_ebp = tp->tf_ebp;
1028 regs->r_ebx = tp->tf_ebx;
1029 regs->r_edx = tp->tf_edx;
1030 regs->r_ecx = tp->tf_ecx;
1031 regs->r_eax = tp->tf_eax;
1032 regs->r_eip = tp->tf_eip;
1033 regs->r_cs = tp->tf_cs;
1034 regs->r_eflags = tp->tf_eflags;
1035 regs->r_esp = tp->tf_esp;
1036 regs->r_ss = tp->tf_ss;
1043 set_regs(struct thread *td, struct reg *regs)
1046 struct trapframe *tp;
1049 if (!EFL_SECURE(regs->r_eflags, tp->tf_eflags) ||
1050 !CS_SECURE(regs->r_cs))
1053 tp->tf_fs = regs->r_fs;
1054 tp->tf_es = regs->r_es;
1055 tp->tf_ds = regs->r_ds;
1056 tp->tf_edi = regs->r_edi;
1057 tp->tf_esi = regs->r_esi;
1058 tp->tf_ebp = regs->r_ebp;
1059 tp->tf_ebx = regs->r_ebx;
1060 tp->tf_edx = regs->r_edx;
1061 tp->tf_ecx = regs->r_ecx;
1062 tp->tf_eax = regs->r_eax;
1063 tp->tf_eip = regs->r_eip;
1064 tp->tf_cs = regs->r_cs;
1065 tp->tf_eflags = regs->r_eflags;
1066 tp->tf_esp = regs->r_esp;
1067 tp->tf_ss = regs->r_ss;
1068 pcb->pcb_gs = regs->r_gs;
1073 fill_fpregs(struct thread *td, struct fpreg *fpregs)
1076 KASSERT(td == curthread || TD_IS_SUSPENDED(td) ||
1077 P_SHOULDSTOP(td->td_proc),
1078 ("not suspended thread %p", td));
1081 npx_fill_fpregs_xmm(&get_pcb_user_save_td(td)->sv_xmm,
1082 (struct save87 *)fpregs);
1084 bcopy(&get_pcb_user_save_td(td)->sv_87, fpregs,
1090 set_fpregs(struct thread *td, struct fpreg *fpregs)
1095 npx_set_fpregs_xmm((struct save87 *)fpregs,
1096 &get_pcb_user_save_td(td)->sv_xmm);
1098 bcopy(fpregs, &get_pcb_user_save_td(td)->sv_87,
1106 * Get machine context.
1109 get_mcontext(struct thread *td, mcontext_t *mcp, int flags)
1111 struct trapframe *tp;
1112 struct segment_descriptor *sdp;
1116 PROC_LOCK(curthread->td_proc);
1117 mcp->mc_onstack = sigonstack(tp->tf_esp);
1118 PROC_UNLOCK(curthread->td_proc);
1119 mcp->mc_gs = td->td_pcb->pcb_gs;
1120 mcp->mc_fs = tp->tf_fs;
1121 mcp->mc_es = tp->tf_es;
1122 mcp->mc_ds = tp->tf_ds;
1123 mcp->mc_edi = tp->tf_edi;
1124 mcp->mc_esi = tp->tf_esi;
1125 mcp->mc_ebp = tp->tf_ebp;
1126 mcp->mc_isp = tp->tf_isp;
1127 mcp->mc_eflags = tp->tf_eflags;
1128 if (flags & GET_MC_CLEAR_RET) {
1131 mcp->mc_eflags &= ~PSL_C;
1133 mcp->mc_eax = tp->tf_eax;
1134 mcp->mc_edx = tp->tf_edx;
1136 mcp->mc_ebx = tp->tf_ebx;
1137 mcp->mc_ecx = tp->tf_ecx;
1138 mcp->mc_eip = tp->tf_eip;
1139 mcp->mc_cs = tp->tf_cs;
1140 mcp->mc_esp = tp->tf_esp;
1141 mcp->mc_ss = tp->tf_ss;
1142 mcp->mc_len = sizeof(*mcp);
1143 get_fpcontext(td, mcp, NULL, 0);
1144 sdp = &td->td_pcb->pcb_fsd;
1145 mcp->mc_fsbase = sdp->sd_hibase << 24 | sdp->sd_lobase;
1146 sdp = &td->td_pcb->pcb_gsd;
1147 mcp->mc_gsbase = sdp->sd_hibase << 24 | sdp->sd_lobase;
1149 mcp->mc_xfpustate = 0;
1150 mcp->mc_xfpustate_len = 0;
1151 bzero(mcp->mc_spare2, sizeof(mcp->mc_spare2));
1156 * Set machine context.
1158 * However, we don't set any but the user modifiable flags, and we won't
1159 * touch the cs selector.
1162 set_mcontext(struct thread *td, mcontext_t *mcp)
1164 struct trapframe *tp;
1169 if (mcp->mc_len != sizeof(*mcp) ||
1170 (mcp->mc_flags & ~_MC_FLAG_MASK) != 0)
1172 eflags = (mcp->mc_eflags & PSL_USERCHANGE) |
1173 (tp->tf_eflags & ~PSL_USERCHANGE);
1174 if (mcp->mc_flags & _MC_HASFPXSTATE) {
1175 if (mcp->mc_xfpustate_len > cpu_max_ext_state_size -
1176 sizeof(union savefpu))
1178 xfpustate = __builtin_alloca(mcp->mc_xfpustate_len);
1179 ret = copyin((void *)mcp->mc_xfpustate, xfpustate,
1180 mcp->mc_xfpustate_len);
1185 ret = set_fpcontext(td, mcp, xfpustate, mcp->mc_xfpustate_len);
1188 tp->tf_fs = mcp->mc_fs;
1189 tp->tf_es = mcp->mc_es;
1190 tp->tf_ds = mcp->mc_ds;
1191 tp->tf_edi = mcp->mc_edi;
1192 tp->tf_esi = mcp->mc_esi;
1193 tp->tf_ebp = mcp->mc_ebp;
1194 tp->tf_ebx = mcp->mc_ebx;
1195 tp->tf_edx = mcp->mc_edx;
1196 tp->tf_ecx = mcp->mc_ecx;
1197 tp->tf_eax = mcp->mc_eax;
1198 tp->tf_eip = mcp->mc_eip;
1199 tp->tf_eflags = eflags;
1200 tp->tf_esp = mcp->mc_esp;
1201 tp->tf_ss = mcp->mc_ss;
1202 td->td_pcb->pcb_gs = mcp->mc_gs;
1207 get_fpcontext(struct thread *td, mcontext_t *mcp, char *xfpusave,
1208 size_t xfpusave_len)
1210 size_t max_len, len;
1212 mcp->mc_ownedfp = npxgetregs(td);
1213 bcopy(get_pcb_user_save_td(td), &mcp->mc_fpstate[0],
1214 sizeof(mcp->mc_fpstate));
1215 mcp->mc_fpformat = npxformat();
1216 if (!use_xsave || xfpusave_len == 0)
1218 max_len = cpu_max_ext_state_size - sizeof(union savefpu);
1220 if (len > max_len) {
1222 bzero(xfpusave + max_len, len - max_len);
1224 mcp->mc_flags |= _MC_HASFPXSTATE;
1225 mcp->mc_xfpustate_len = len;
1226 bcopy(get_pcb_user_save_td(td) + 1, xfpusave, len);
1230 set_fpcontext(struct thread *td, mcontext_t *mcp, char *xfpustate,
1231 size_t xfpustate_len)
1235 if (mcp->mc_fpformat == _MC_FPFMT_NODEV)
1237 else if (mcp->mc_fpformat != _MC_FPFMT_387 &&
1238 mcp->mc_fpformat != _MC_FPFMT_XMM)
1240 else if (mcp->mc_ownedfp == _MC_FPOWNED_NONE) {
1241 /* We don't care what state is left in the FPU or PCB. */
1244 } else if (mcp->mc_ownedfp == _MC_FPOWNED_FPU ||
1245 mcp->mc_ownedfp == _MC_FPOWNED_PCB) {
1246 error = npxsetregs(td, (union savefpu *)&mcp->mc_fpstate,
1247 xfpustate, xfpustate_len);
1254 fpstate_drop(struct thread *td)
1257 KASSERT(PCB_USER_FPU(td->td_pcb), ("fpstate_drop: kernel-owned fpu"));
1259 if (PCPU_GET(fpcurthread) == td)
1262 * XXX force a full drop of the npx. The above only drops it if we
1263 * owned it. npxgetregs() has the same bug in the !cpu_fxsr case.
1265 * XXX I don't much like npxgetregs()'s semantics of doing a full
1266 * drop. Dropping only to the pcb matches fnsave's behaviour.
1267 * We only need to drop to !PCB_INITDONE in sendsig(). But
1268 * sendsig() is the only caller of npxgetregs()... perhaps we just
1269 * have too many layers.
1271 curthread->td_pcb->pcb_flags &= ~(PCB_NPXINITDONE |
1272 PCB_NPXUSERINITDONE);
1277 fill_dbregs(struct thread *td, struct dbreg *dbregs)
1282 dbregs->dr[0] = rdr0();
1283 dbregs->dr[1] = rdr1();
1284 dbregs->dr[2] = rdr2();
1285 dbregs->dr[3] = rdr3();
1286 dbregs->dr[6] = rdr6();
1287 dbregs->dr[7] = rdr7();
1290 dbregs->dr[0] = pcb->pcb_dr0;
1291 dbregs->dr[1] = pcb->pcb_dr1;
1292 dbregs->dr[2] = pcb->pcb_dr2;
1293 dbregs->dr[3] = pcb->pcb_dr3;
1294 dbregs->dr[6] = pcb->pcb_dr6;
1295 dbregs->dr[7] = pcb->pcb_dr7;
1303 set_dbregs(struct thread *td, struct dbreg *dbregs)
1309 load_dr0(dbregs->dr[0]);
1310 load_dr1(dbregs->dr[1]);
1311 load_dr2(dbregs->dr[2]);
1312 load_dr3(dbregs->dr[3]);
1313 load_dr6(dbregs->dr[6]);
1314 load_dr7(dbregs->dr[7]);
1317 * Don't let an illegal value for dr7 get set. Specifically,
1318 * check for undefined settings. Setting these bit patterns
1319 * result in undefined behaviour and can lead to an unexpected
1322 for (i = 0; i < 4; i++) {
1323 if (DBREG_DR7_ACCESS(dbregs->dr[7], i) == 0x02)
1325 if (DBREG_DR7_LEN(dbregs->dr[7], i) == 0x02)
1332 * Don't let a process set a breakpoint that is not within the
1333 * process's address space. If a process could do this, it
1334 * could halt the system by setting a breakpoint in the kernel
1335 * (if ddb was enabled). Thus, we need to check to make sure
1336 * that no breakpoints are being enabled for addresses outside
1337 * process's address space.
1339 * XXX - what about when the watched area of the user's
1340 * address space is written into from within the kernel
1341 * ... wouldn't that still cause a breakpoint to be generated
1342 * from within kernel mode?
1345 if (DBREG_DR7_ENABLED(dbregs->dr[7], 0)) {
1346 /* dr0 is enabled */
1347 if (dbregs->dr[0] >= VM_MAXUSER_ADDRESS)
1351 if (DBREG_DR7_ENABLED(dbregs->dr[7], 1)) {
1352 /* dr1 is enabled */
1353 if (dbregs->dr[1] >= VM_MAXUSER_ADDRESS)
1357 if (DBREG_DR7_ENABLED(dbregs->dr[7], 2)) {
1358 /* dr2 is enabled */
1359 if (dbregs->dr[2] >= VM_MAXUSER_ADDRESS)
1363 if (DBREG_DR7_ENABLED(dbregs->dr[7], 3)) {
1364 /* dr3 is enabled */
1365 if (dbregs->dr[3] >= VM_MAXUSER_ADDRESS)
1369 pcb->pcb_dr0 = dbregs->dr[0];
1370 pcb->pcb_dr1 = dbregs->dr[1];
1371 pcb->pcb_dr2 = dbregs->dr[2];
1372 pcb->pcb_dr3 = dbregs->dr[3];
1373 pcb->pcb_dr6 = dbregs->dr[6];
1374 pcb->pcb_dr7 = dbregs->dr[7];
1376 pcb->pcb_flags |= PCB_DBREGS;
1383 * Return > 0 if a hardware breakpoint has been hit, and the
1384 * breakpoint was in user space. Return 0, otherwise.
1387 user_dbreg_trap(register_t dr6)
1390 u_int32_t bp; /* breakpoint bits extracted from dr6 */
1391 int nbp; /* number of breakpoints that triggered */
1392 caddr_t addr[4]; /* breakpoint addresses */
1395 bp = dr6 & DBREG_DR6_BMASK;
1398 * None of the breakpoint bits are set meaning this
1399 * trap was not caused by any of the debug registers
1405 if ((dr7 & 0x000000ff) == 0) {
1407 * all GE and LE bits in the dr7 register are zero,
1408 * thus the trap couldn't have been caused by the
1409 * hardware debug registers
1417 * at least one of the breakpoints were hit, check to see
1418 * which ones and if any of them are user space addresses
1422 addr[nbp++] = (caddr_t)rdr0();
1425 addr[nbp++] = (caddr_t)rdr1();
1428 addr[nbp++] = (caddr_t)rdr2();
1431 addr[nbp++] = (caddr_t)rdr3();
1434 for (i = 0; i < nbp; i++) {
1435 if (addr[i] < (caddr_t)VM_MAXUSER_ADDRESS) {
1437 * addr[i] is in user space
1444 * None of the breakpoints are in user space.