2 * SPDX-License-Identifier: BSD-4-Clause
4 * Copyright (c) 2003 Peter Wemm.
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 * Redistribution and use in source and binary forms, with or without
13 * modification, are permitted provided that the following conditions
15 * 1. Redistributions of source code must retain the above copyright
16 * notice, this list of conditions and the following disclaimer.
17 * 2. Redistributions in binary form must reproduce the above copyright
18 * notice, this list of conditions and the following disclaimer in the
19 * documentation and/or other materials provided with the distribution.
20 * 3. All advertising materials mentioning features or use of this software
21 * must display the following acknowledgement:
22 * This product includes software developed by the University of
23 * California, Berkeley and its contributors.
24 * 4. Neither the name of the University nor the names of its contributors
25 * may be used to endorse or promote products derived from this software
26 * without specific prior written permission.
28 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
29 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
30 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
31 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
32 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
33 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
34 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
35 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
36 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
37 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
40 * from: @(#)machdep.c 7.4 (Berkeley) 6/3/91
43 #include <sys/cdefs.h>
44 __FBSDID("$FreeBSD$");
48 #include "opt_kstack_pages.h"
50 #include <sys/param.h>
52 #include <sys/systm.h>
54 #include <sys/imgact.h>
56 #include <sys/kernel.h>
58 #include <sys/linker.h>
60 #include <sys/malloc.h>
61 #include <sys/mutex.h>
64 #include <sys/rwlock.h>
65 #include <sys/signalvar.h>
69 #include <sys/syscallsubr.h>
70 #include <sys/sysctl.h>
71 #include <sys/sysent.h>
72 #include <sys/sysproto.h>
73 #include <sys/ucontext.h>
74 #include <sys/vmmeter.h>
77 #include <vm/vm_param.h>
78 #include <vm/vm_extern.h>
83 #error KDB must be enabled in order for DDB to work!
86 #include <ddb/db_sym.h>
89 #include <machine/vmparam.h>
90 #include <machine/frame.h>
91 #include <machine/md_var.h>
92 #include <machine/pcb.h>
93 #include <machine/proc.h>
94 #include <machine/sigframe.h>
95 #include <machine/specialreg.h>
96 #include <machine/trap.h>
98 static void get_fpcontext(struct thread *td, mcontext_t *mcp,
99 char **xfpusave, size_t *xfpusave_len);
100 static int set_fpcontext(struct thread *td, mcontext_t *mcp,
101 char *xfpustate, size_t xfpustate_len);
104 * Send an interrupt to process.
106 * Stack is set up to allow sigcode stored at top to call routine,
107 * followed by call to sigreturn routine below. After sigreturn
108 * resets the signal mask, the stack, and the frame pointer, it
109 * returns to the user specified pc, psl.
112 sendsig(sig_t catcher, ksiginfo_t *ksi, sigset_t *mask)
114 struct sigframe sf, *sfp;
120 struct trapframe *regs;
129 PROC_LOCK_ASSERT(p, MA_OWNED);
130 sig = ksi->ksi_signo;
132 mtx_assert(&psp->ps_mtx, MA_OWNED);
134 oonstack = sigonstack(regs->tf_rsp);
136 /* Save user context. */
137 bzero(&sf, sizeof(sf));
138 sf.sf_uc.uc_sigmask = *mask;
139 sf.sf_uc.uc_stack = td->td_sigstk;
140 sf.sf_uc.uc_stack.ss_flags = (td->td_pflags & TDP_ALTSTACK)
141 ? ((oonstack) ? SS_ONSTACK : 0) : SS_DISABLE;
142 sf.sf_uc.uc_mcontext.mc_onstack = (oonstack) ? 1 : 0;
143 bcopy(regs, &sf.sf_uc.uc_mcontext.mc_rdi, sizeof(*regs));
144 sf.sf_uc.uc_mcontext.mc_len = sizeof(sf.sf_uc.uc_mcontext); /* magic */
145 get_fpcontext(td, &sf.sf_uc.uc_mcontext, &xfpusave, &xfpusave_len);
146 update_pcb_bases(pcb);
147 sf.sf_uc.uc_mcontext.mc_fsbase = pcb->pcb_fsbase;
148 sf.sf_uc.uc_mcontext.mc_gsbase = pcb->pcb_gsbase;
149 bzero(sf.sf_uc.uc_mcontext.mc_spare,
150 sizeof(sf.sf_uc.uc_mcontext.mc_spare));
152 /* Allocate space for the signal handler context. */
153 if ((td->td_pflags & TDP_ALTSTACK) != 0 && !oonstack &&
154 SIGISMEMBER(psp->ps_sigonstack, sig)) {
155 sp = (char *)td->td_sigstk.ss_sp + td->td_sigstk.ss_size;
156 #if defined(COMPAT_43)
157 td->td_sigstk.ss_flags |= SS_ONSTACK;
160 sp = (char *)regs->tf_rsp - 128;
161 if (xfpusave != NULL) {
163 sp = (char *)((unsigned long)sp & ~0x3Ful);
164 sf.sf_uc.uc_mcontext.mc_xfpustate = (register_t)sp;
166 sp -= sizeof(struct sigframe);
167 /* Align to 16 bytes. */
168 sfp = (struct sigframe *)((unsigned long)sp & ~0xFul);
170 /* Build the argument list for the signal handler. */
171 regs->tf_rdi = sig; /* arg 1 in %rdi */
172 regs->tf_rdx = (register_t)&sfp->sf_uc; /* arg 3 in %rdx */
173 bzero(&sf.sf_si, sizeof(sf.sf_si));
174 if (SIGISMEMBER(psp->ps_siginfo, sig)) {
175 /* Signal handler installed with SA_SIGINFO. */
176 regs->tf_rsi = (register_t)&sfp->sf_si; /* arg 2 in %rsi */
177 sf.sf_ahu.sf_action = (__siginfohandler_t *)catcher;
179 /* Fill in POSIX parts */
180 sf.sf_si = ksi->ksi_info;
181 sf.sf_si.si_signo = sig; /* maybe a translated signal */
182 regs->tf_rcx = (register_t)ksi->ksi_addr; /* arg 4 in %rcx */
184 /* Old FreeBSD-style arguments. */
185 regs->tf_rsi = ksi->ksi_code; /* arg 2 in %rsi */
186 regs->tf_rcx = (register_t)ksi->ksi_addr; /* arg 4 in %rcx */
187 sf.sf_ahu.sf_handler = catcher;
189 mtx_unlock(&psp->ps_mtx);
193 * Copy the sigframe out to the user's stack.
195 if (copyout(&sf, sfp, sizeof(*sfp)) != 0 ||
196 (xfpusave != NULL && copyout(xfpusave,
197 (void *)sf.sf_uc.uc_mcontext.mc_xfpustate, xfpusave_len)
199 uprintf("pid %d comm %s has trashed its stack, killing\n",
200 p->p_pid, p->p_comm);
206 regs->tf_rsp = (long)sfp;
207 regs->tf_rip = p->p_sysent->sv_sigcode_base;
208 regs->tf_rflags &= ~(PSL_T | PSL_D);
209 regs->tf_cs = _ucodesel;
210 regs->tf_ds = _udatasel;
211 regs->tf_ss = _udatasel;
212 regs->tf_es = _udatasel;
213 regs->tf_fs = _ufssel;
214 regs->tf_gs = _ugssel;
215 regs->tf_flags = TF_HASSEGS;
217 mtx_lock(&psp->ps_mtx);
221 * System call to cleanup state after a signal
222 * has been taken. Reset signal mask and
223 * stack state from context left by sendsig (above).
224 * Return to previous pc and psl as specified by
225 * context left by sendsig. Check carefully to
226 * make sure that the user has not modified the
227 * state to gain improper privileges.
230 sys_sigreturn(struct thread *td, struct sigreturn_args *uap)
235 struct trapframe *regs;
238 size_t xfpustate_len;
246 error = copyin(uap->sigcntxp, &uc, sizeof(uc));
248 uprintf("pid %d (%s): sigreturn copyin failed\n",
249 p->p_pid, td->td_name);
253 if ((ucp->uc_mcontext.mc_flags & ~_MC_FLAG_MASK) != 0) {
254 uprintf("pid %d (%s): sigreturn mc_flags %x\n", p->p_pid,
255 td->td_name, ucp->uc_mcontext.mc_flags);
259 rflags = ucp->uc_mcontext.mc_rflags;
261 * Don't allow users to change privileged or reserved flags.
263 if (!EFL_SECURE(rflags, regs->tf_rflags)) {
264 uprintf("pid %d (%s): sigreturn rflags = 0x%lx\n", p->p_pid,
265 td->td_name, rflags);
270 * Don't allow users to load a valid privileged %cs. Let the
271 * hardware check for invalid selectors, excess privilege in
272 * other selectors, invalid %eip's and invalid %esp's.
274 cs = ucp->uc_mcontext.mc_cs;
275 if (!CS_SECURE(cs)) {
276 uprintf("pid %d (%s): sigreturn cs = 0x%x\n", p->p_pid,
278 ksiginfo_init_trap(&ksi);
279 ksi.ksi_signo = SIGBUS;
280 ksi.ksi_code = BUS_OBJERR;
281 ksi.ksi_trapno = T_PROTFLT;
282 ksi.ksi_addr = (void *)regs->tf_rip;
283 trapsignal(td, &ksi);
287 if ((uc.uc_mcontext.mc_flags & _MC_HASFPXSTATE) != 0) {
288 xfpustate_len = uc.uc_mcontext.mc_xfpustate_len;
289 if (xfpustate_len > cpu_max_ext_state_size -
290 sizeof(struct savefpu)) {
291 uprintf("pid %d (%s): sigreturn xfpusave_len = 0x%zx\n",
292 p->p_pid, td->td_name, xfpustate_len);
295 xfpustate = (char *)fpu_save_area_alloc();
296 error = copyin((const void *)uc.uc_mcontext.mc_xfpustate,
297 xfpustate, xfpustate_len);
299 fpu_save_area_free((struct savefpu *)xfpustate);
301 "pid %d (%s): sigreturn copying xfpustate failed\n",
302 p->p_pid, td->td_name);
309 ret = set_fpcontext(td, &ucp->uc_mcontext, xfpustate, xfpustate_len);
310 fpu_save_area_free((struct savefpu *)xfpustate);
312 uprintf("pid %d (%s): sigreturn set_fpcontext err %d\n",
313 p->p_pid, td->td_name, ret);
316 bcopy(&ucp->uc_mcontext.mc_rdi, regs, sizeof(*regs));
317 update_pcb_bases(pcb);
318 pcb->pcb_fsbase = ucp->uc_mcontext.mc_fsbase;
319 pcb->pcb_gsbase = ucp->uc_mcontext.mc_gsbase;
321 #if defined(COMPAT_43)
322 if (ucp->uc_mcontext.mc_onstack & 1)
323 td->td_sigstk.ss_flags |= SS_ONSTACK;
325 td->td_sigstk.ss_flags &= ~SS_ONSTACK;
328 kern_sigprocmask(td, SIG_SETMASK, &ucp->uc_sigmask, NULL, 0);
329 return (EJUSTRETURN);
332 #ifdef COMPAT_FREEBSD4
334 freebsd4_sigreturn(struct thread *td, struct freebsd4_sigreturn_args *uap)
337 return sys_sigreturn(td, (struct sigreturn_args *)uap);
342 * Reset the hardware debug registers if they were in use.
343 * They won't have any meaning for the newly exec'd process.
346 x86_clear_dbregs(struct pcb *pcb)
348 if ((pcb->pcb_flags & PCB_DBREGS) == 0)
360 * Clear the debug registers on the running CPU,
361 * otherwise they will end up affecting the next
362 * process we switch to.
366 clear_pcb_flags(pcb, PCB_DBREGS);
370 * Reset registers to default values on exec.
373 exec_setregs(struct thread *td, struct image_params *imgp, uintptr_t stack)
375 struct trapframe *regs;
377 register_t saved_rflags;
382 if (td->td_proc->p_md.md_ldt != NULL)
385 update_pcb_bases(pcb);
388 clear_pcb_flags(pcb, PCB_32BIT);
389 pcb->pcb_initial_fpucw = __INITIAL_FPUCW__;
391 saved_rflags = regs->tf_rflags & PSL_T;
392 bzero((char *)regs, sizeof(struct trapframe));
393 regs->tf_rip = imgp->entry_addr;
394 regs->tf_rsp = ((stack - 8) & ~0xFul) + 8;
395 regs->tf_rdi = stack; /* argv */
396 regs->tf_rflags = PSL_USER | saved_rflags;
397 regs->tf_ss = _udatasel;
398 regs->tf_cs = _ucodesel;
399 regs->tf_ds = _udatasel;
400 regs->tf_es = _udatasel;
401 regs->tf_fs = _ufssel;
402 regs->tf_gs = _ugssel;
403 regs->tf_flags = TF_HASSEGS;
405 x86_clear_dbregs(pcb);
408 * Drop the FP state if we hold it, so that the process gets a
409 * clean FP state if it uses the FPU again.
415 fill_regs(struct thread *td, struct reg *regs)
417 struct trapframe *tp;
420 return (fill_frame_regs(tp, regs));
424 fill_frame_regs(struct trapframe *tp, struct reg *regs)
427 regs->r_r15 = tp->tf_r15;
428 regs->r_r14 = tp->tf_r14;
429 regs->r_r13 = tp->tf_r13;
430 regs->r_r12 = tp->tf_r12;
431 regs->r_r11 = tp->tf_r11;
432 regs->r_r10 = tp->tf_r10;
433 regs->r_r9 = tp->tf_r9;
434 regs->r_r8 = tp->tf_r8;
435 regs->r_rdi = tp->tf_rdi;
436 regs->r_rsi = tp->tf_rsi;
437 regs->r_rbp = tp->tf_rbp;
438 regs->r_rbx = tp->tf_rbx;
439 regs->r_rdx = tp->tf_rdx;
440 regs->r_rcx = tp->tf_rcx;
441 regs->r_rax = tp->tf_rax;
442 regs->r_rip = tp->tf_rip;
443 regs->r_cs = tp->tf_cs;
444 regs->r_rflags = tp->tf_rflags;
445 regs->r_rsp = tp->tf_rsp;
446 regs->r_ss = tp->tf_ss;
447 if (tp->tf_flags & TF_HASSEGS) {
448 regs->r_ds = tp->tf_ds;
449 regs->r_es = tp->tf_es;
450 regs->r_fs = tp->tf_fs;
451 regs->r_gs = tp->tf_gs;
464 set_regs(struct thread *td, struct reg *regs)
466 struct trapframe *tp;
470 rflags = regs->r_rflags & 0xffffffff;
471 if (!EFL_SECURE(rflags, tp->tf_rflags) || !CS_SECURE(regs->r_cs))
473 tp->tf_r15 = regs->r_r15;
474 tp->tf_r14 = regs->r_r14;
475 tp->tf_r13 = regs->r_r13;
476 tp->tf_r12 = regs->r_r12;
477 tp->tf_r11 = regs->r_r11;
478 tp->tf_r10 = regs->r_r10;
479 tp->tf_r9 = regs->r_r9;
480 tp->tf_r8 = regs->r_r8;
481 tp->tf_rdi = regs->r_rdi;
482 tp->tf_rsi = regs->r_rsi;
483 tp->tf_rbp = regs->r_rbp;
484 tp->tf_rbx = regs->r_rbx;
485 tp->tf_rdx = regs->r_rdx;
486 tp->tf_rcx = regs->r_rcx;
487 tp->tf_rax = regs->r_rax;
488 tp->tf_rip = regs->r_rip;
489 tp->tf_cs = regs->r_cs;
490 tp->tf_rflags = rflags;
491 tp->tf_rsp = regs->r_rsp;
492 tp->tf_ss = regs->r_ss;
493 if (0) { /* XXXKIB */
494 tp->tf_ds = regs->r_ds;
495 tp->tf_es = regs->r_es;
496 tp->tf_fs = regs->r_fs;
497 tp->tf_gs = regs->r_gs;
498 tp->tf_flags = TF_HASSEGS;
500 set_pcb_flags(td->td_pcb, PCB_FULL_IRET);
504 /* XXX check all this stuff! */
505 /* externalize from sv_xmm */
507 fill_fpregs_xmm(struct savefpu *sv_xmm, struct fpreg *fpregs)
509 struct envxmm *penv_fpreg = (struct envxmm *)&fpregs->fpr_env;
510 struct envxmm *penv_xmm = &sv_xmm->sv_env;
514 bzero(fpregs, sizeof(*fpregs));
516 /* FPU control/status */
517 penv_fpreg->en_cw = penv_xmm->en_cw;
518 penv_fpreg->en_sw = penv_xmm->en_sw;
519 penv_fpreg->en_tw = penv_xmm->en_tw;
520 penv_fpreg->en_opcode = penv_xmm->en_opcode;
521 penv_fpreg->en_rip = penv_xmm->en_rip;
522 penv_fpreg->en_rdp = penv_xmm->en_rdp;
523 penv_fpreg->en_mxcsr = penv_xmm->en_mxcsr;
524 penv_fpreg->en_mxcsr_mask = penv_xmm->en_mxcsr_mask;
527 for (i = 0; i < 8; ++i)
528 bcopy(sv_xmm->sv_fp[i].fp_acc.fp_bytes, fpregs->fpr_acc[i], 10);
531 for (i = 0; i < 16; ++i)
532 bcopy(sv_xmm->sv_xmm[i].xmm_bytes, fpregs->fpr_xacc[i], 16);
535 /* internalize from fpregs into sv_xmm */
537 set_fpregs_xmm(struct fpreg *fpregs, struct savefpu *sv_xmm)
539 struct envxmm *penv_xmm = &sv_xmm->sv_env;
540 struct envxmm *penv_fpreg = (struct envxmm *)&fpregs->fpr_env;
544 /* FPU control/status */
545 penv_xmm->en_cw = penv_fpreg->en_cw;
546 penv_xmm->en_sw = penv_fpreg->en_sw;
547 penv_xmm->en_tw = penv_fpreg->en_tw;
548 penv_xmm->en_opcode = penv_fpreg->en_opcode;
549 penv_xmm->en_rip = penv_fpreg->en_rip;
550 penv_xmm->en_rdp = penv_fpreg->en_rdp;
551 penv_xmm->en_mxcsr = penv_fpreg->en_mxcsr;
552 penv_xmm->en_mxcsr_mask = penv_fpreg->en_mxcsr_mask & cpu_mxcsr_mask;
555 for (i = 0; i < 8; ++i)
556 bcopy(fpregs->fpr_acc[i], sv_xmm->sv_fp[i].fp_acc.fp_bytes, 10);
559 for (i = 0; i < 16; ++i)
560 bcopy(fpregs->fpr_xacc[i], sv_xmm->sv_xmm[i].xmm_bytes, 16);
563 /* externalize from td->pcb */
565 fill_fpregs(struct thread *td, struct fpreg *fpregs)
568 KASSERT(td == curthread || TD_IS_SUSPENDED(td) ||
569 P_SHOULDSTOP(td->td_proc),
570 ("not suspended thread %p", td));
572 fill_fpregs_xmm(get_pcb_user_save_td(td), fpregs);
576 /* internalize to td->pcb */
578 set_fpregs(struct thread *td, struct fpreg *fpregs)
582 set_fpregs_xmm(fpregs, get_pcb_user_save_td(td));
589 * Get machine context.
592 get_mcontext(struct thread *td, mcontext_t *mcp, int flags)
595 struct trapframe *tp;
599 PROC_LOCK(curthread->td_proc);
600 mcp->mc_onstack = sigonstack(tp->tf_rsp);
601 PROC_UNLOCK(curthread->td_proc);
602 mcp->mc_r15 = tp->tf_r15;
603 mcp->mc_r14 = tp->tf_r14;
604 mcp->mc_r13 = tp->tf_r13;
605 mcp->mc_r12 = tp->tf_r12;
606 mcp->mc_r11 = tp->tf_r11;
607 mcp->mc_r10 = tp->tf_r10;
608 mcp->mc_r9 = tp->tf_r9;
609 mcp->mc_r8 = tp->tf_r8;
610 mcp->mc_rdi = tp->tf_rdi;
611 mcp->mc_rsi = tp->tf_rsi;
612 mcp->mc_rbp = tp->tf_rbp;
613 mcp->mc_rbx = tp->tf_rbx;
614 mcp->mc_rcx = tp->tf_rcx;
615 mcp->mc_rflags = tp->tf_rflags;
616 if (flags & GET_MC_CLEAR_RET) {
619 mcp->mc_rflags &= ~PSL_C;
621 mcp->mc_rax = tp->tf_rax;
622 mcp->mc_rdx = tp->tf_rdx;
624 mcp->mc_rip = tp->tf_rip;
625 mcp->mc_cs = tp->tf_cs;
626 mcp->mc_rsp = tp->tf_rsp;
627 mcp->mc_ss = tp->tf_ss;
628 mcp->mc_ds = tp->tf_ds;
629 mcp->mc_es = tp->tf_es;
630 mcp->mc_fs = tp->tf_fs;
631 mcp->mc_gs = tp->tf_gs;
632 mcp->mc_flags = tp->tf_flags;
633 mcp->mc_len = sizeof(*mcp);
634 get_fpcontext(td, mcp, NULL, NULL);
635 update_pcb_bases(pcb);
636 mcp->mc_fsbase = pcb->pcb_fsbase;
637 mcp->mc_gsbase = pcb->pcb_gsbase;
638 mcp->mc_xfpustate = 0;
639 mcp->mc_xfpustate_len = 0;
640 bzero(mcp->mc_spare, sizeof(mcp->mc_spare));
645 * Set machine context.
647 * However, we don't set any but the user modifiable flags, and we won't
648 * touch the cs selector.
651 set_mcontext(struct thread *td, mcontext_t *mcp)
654 struct trapframe *tp;
661 if (mcp->mc_len != sizeof(*mcp) ||
662 (mcp->mc_flags & ~_MC_FLAG_MASK) != 0)
664 rflags = (mcp->mc_rflags & PSL_USERCHANGE) |
665 (tp->tf_rflags & ~PSL_USERCHANGE);
666 if (mcp->mc_flags & _MC_HASFPXSTATE) {
667 if (mcp->mc_xfpustate_len > cpu_max_ext_state_size -
668 sizeof(struct savefpu))
670 xfpustate = (char *)fpu_save_area_alloc();
671 ret = copyin((void *)mcp->mc_xfpustate, xfpustate,
672 mcp->mc_xfpustate_len);
674 fpu_save_area_free((struct savefpu *)xfpustate);
679 ret = set_fpcontext(td, mcp, xfpustate, mcp->mc_xfpustate_len);
680 fpu_save_area_free((struct savefpu *)xfpustate);
683 tp->tf_r15 = mcp->mc_r15;
684 tp->tf_r14 = mcp->mc_r14;
685 tp->tf_r13 = mcp->mc_r13;
686 tp->tf_r12 = mcp->mc_r12;
687 tp->tf_r11 = mcp->mc_r11;
688 tp->tf_r10 = mcp->mc_r10;
689 tp->tf_r9 = mcp->mc_r9;
690 tp->tf_r8 = mcp->mc_r8;
691 tp->tf_rdi = mcp->mc_rdi;
692 tp->tf_rsi = mcp->mc_rsi;
693 tp->tf_rbp = mcp->mc_rbp;
694 tp->tf_rbx = mcp->mc_rbx;
695 tp->tf_rdx = mcp->mc_rdx;
696 tp->tf_rcx = mcp->mc_rcx;
697 tp->tf_rax = mcp->mc_rax;
698 tp->tf_rip = mcp->mc_rip;
699 tp->tf_rflags = rflags;
700 tp->tf_rsp = mcp->mc_rsp;
701 tp->tf_ss = mcp->mc_ss;
702 tp->tf_flags = mcp->mc_flags;
703 if (tp->tf_flags & TF_HASSEGS) {
704 tp->tf_ds = mcp->mc_ds;
705 tp->tf_es = mcp->mc_es;
706 tp->tf_fs = mcp->mc_fs;
707 tp->tf_gs = mcp->mc_gs;
709 set_pcb_flags(pcb, PCB_FULL_IRET);
710 if (mcp->mc_flags & _MC_HASBASES) {
711 pcb->pcb_fsbase = mcp->mc_fsbase;
712 pcb->pcb_gsbase = mcp->mc_gsbase;
718 get_fpcontext(struct thread *td, mcontext_t *mcp, char **xfpusave,
719 size_t *xfpusave_len)
721 mcp->mc_ownedfp = fpugetregs(td);
722 bcopy(get_pcb_user_save_td(td), &mcp->mc_fpstate[0],
723 sizeof(mcp->mc_fpstate));
724 mcp->mc_fpformat = fpuformat();
725 if (xfpusave == NULL)
727 if (!use_xsave || cpu_max_ext_state_size <= sizeof(struct savefpu)) {
731 mcp->mc_flags |= _MC_HASFPXSTATE;
732 *xfpusave_len = mcp->mc_xfpustate_len =
733 cpu_max_ext_state_size - sizeof(struct savefpu);
734 *xfpusave = (char *)(get_pcb_user_save_td(td) + 1);
739 set_fpcontext(struct thread *td, mcontext_t *mcp, char *xfpustate,
740 size_t xfpustate_len)
744 if (mcp->mc_fpformat == _MC_FPFMT_NODEV)
746 else if (mcp->mc_fpformat != _MC_FPFMT_XMM)
748 else if (mcp->mc_ownedfp == _MC_FPOWNED_NONE) {
749 /* We don't care what state is left in the FPU or PCB. */
752 } else if (mcp->mc_ownedfp == _MC_FPOWNED_FPU ||
753 mcp->mc_ownedfp == _MC_FPOWNED_PCB) {
754 error = fpusetregs(td, (struct savefpu *)&mcp->mc_fpstate,
755 xfpustate, xfpustate_len);
762 fpstate_drop(struct thread *td)
765 KASSERT(PCB_USER_FPU(td->td_pcb), ("fpstate_drop: kernel-owned fpu"));
767 if (PCPU_GET(fpcurthread) == td)
770 * XXX force a full drop of the fpu. The above only drops it if we
773 * XXX I don't much like fpugetuserregs()'s semantics of doing a full
774 * drop. Dropping only to the pcb matches fnsave's behaviour.
775 * We only need to drop to !PCB_INITDONE in sendsig(). But
776 * sendsig() is the only caller of fpugetuserregs()... perhaps we just
777 * have too many layers.
779 clear_pcb_flags(curthread->td_pcb,
780 PCB_FPUINITDONE | PCB_USERFPUINITDONE);
785 fill_dbregs(struct thread *td, struct dbreg *dbregs)
790 dbregs->dr[0] = rdr0();
791 dbregs->dr[1] = rdr1();
792 dbregs->dr[2] = rdr2();
793 dbregs->dr[3] = rdr3();
794 dbregs->dr[6] = rdr6();
795 dbregs->dr[7] = rdr7();
798 dbregs->dr[0] = pcb->pcb_dr0;
799 dbregs->dr[1] = pcb->pcb_dr1;
800 dbregs->dr[2] = pcb->pcb_dr2;
801 dbregs->dr[3] = pcb->pcb_dr3;
802 dbregs->dr[6] = pcb->pcb_dr6;
803 dbregs->dr[7] = pcb->pcb_dr7;
819 set_dbregs(struct thread *td, struct dbreg *dbregs)
825 load_dr0(dbregs->dr[0]);
826 load_dr1(dbregs->dr[1]);
827 load_dr2(dbregs->dr[2]);
828 load_dr3(dbregs->dr[3]);
829 load_dr6(dbregs->dr[6]);
830 load_dr7(dbregs->dr[7]);
833 * Don't let an illegal value for dr7 get set. Specifically,
834 * check for undefined settings. Setting these bit patterns
835 * result in undefined behaviour and can lead to an unexpected
836 * TRCTRAP or a general protection fault right here.
837 * Upper bits of dr6 and dr7 must not be set
839 for (i = 0; i < 4; i++) {
840 if (DBREG_DR7_ACCESS(dbregs->dr[7], i) == 0x02)
842 if (td->td_frame->tf_cs == _ucode32sel &&
843 DBREG_DR7_LEN(dbregs->dr[7], i) == DBREG_DR7_LEN_8)
846 if ((dbregs->dr[6] & 0xffffffff00000000ul) != 0 ||
847 (dbregs->dr[7] & 0xffffffff00000000ul) != 0)
853 * Don't let a process set a breakpoint that is not within the
854 * process's address space. If a process could do this, it
855 * could halt the system by setting a breakpoint in the kernel
856 * (if ddb was enabled). Thus, we need to check to make sure
857 * that no breakpoints are being enabled for addresses outside
858 * process's address space.
860 * XXX - what about when the watched area of the user's
861 * address space is written into from within the kernel
862 * ... wouldn't that still cause a breakpoint to be generated
863 * from within kernel mode?
866 if (DBREG_DR7_ENABLED(dbregs->dr[7], 0)) {
868 if (dbregs->dr[0] >= VM_MAXUSER_ADDRESS)
871 if (DBREG_DR7_ENABLED(dbregs->dr[7], 1)) {
873 if (dbregs->dr[1] >= VM_MAXUSER_ADDRESS)
876 if (DBREG_DR7_ENABLED(dbregs->dr[7], 2)) {
878 if (dbregs->dr[2] >= VM_MAXUSER_ADDRESS)
881 if (DBREG_DR7_ENABLED(dbregs->dr[7], 3)) {
883 if (dbregs->dr[3] >= VM_MAXUSER_ADDRESS)
887 pcb->pcb_dr0 = dbregs->dr[0];
888 pcb->pcb_dr1 = dbregs->dr[1];
889 pcb->pcb_dr2 = dbregs->dr[2];
890 pcb->pcb_dr3 = dbregs->dr[3];
891 pcb->pcb_dr6 = dbregs->dr[6];
892 pcb->pcb_dr7 = dbregs->dr[7];
894 set_pcb_flags(pcb, PCB_DBREGS);
904 load_dr7(0); /* Turn off the control bits first */
913 * Return > 0 if a hardware breakpoint has been hit, and the
914 * breakpoint was in user space. Return 0, otherwise.
917 user_dbreg_trap(register_t dr6)
920 u_int64_t bp; /* breakpoint bits extracted from dr6 */
921 int nbp; /* number of breakpoints that triggered */
922 caddr_t addr[4]; /* breakpoint addresses */
925 bp = dr6 & DBREG_DR6_BMASK;
928 * None of the breakpoint bits are set meaning this
929 * trap was not caused by any of the debug registers
935 if ((dr7 & 0x000000ff) == 0) {
937 * all GE and LE bits in the dr7 register are zero,
938 * thus the trap couldn't have been caused by the
939 * hardware debug registers
947 * at least one of the breakpoints were hit, check to see
948 * which ones and if any of them are user space addresses
952 addr[nbp++] = (caddr_t)rdr0();
955 addr[nbp++] = (caddr_t)rdr1();
958 addr[nbp++] = (caddr_t)rdr2();
961 addr[nbp++] = (caddr_t)rdr3();
964 for (i = 0; i < nbp; i++) {
965 if (addr[i] < (caddr_t)VM_MAXUSER_ADDRESS) {
967 * addr[i] is in user space
974 * None of the breakpoints are in user space.