2 * Copyright (c) 2014 Andrew Turner
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28 #include <sys/cdefs.h>
29 __FBSDID("$FreeBSD$");
31 #include <sys/param.h>
32 #include <sys/systm.h>
33 #include <sys/kernel.h>
36 #include <sys/mutex.h>
38 #include <sys/ptrace.h>
39 #include <sys/syscall.h>
40 #include <sys/sysent.h>
47 #include <vm/vm_kern.h>
48 #include <vm/vm_map.h>
49 #include <vm/vm_param.h>
50 #include <vm/vm_extern.h>
52 #include <machine/frame.h>
53 #include <machine/pcb.h>
54 #include <machine/pcpu.h>
55 #include <machine/undefined.h>
58 #include <sys/dtrace_bsd.h>
62 #include <machine/vfp.h>
66 #include <machine/db_machdep.h>
70 #include <ddb/db_output.h>
73 extern register_t fsu_intr_fault;
75 /* Called from exception.S */
76 void do_el1h_sync(struct thread *, struct trapframe *);
77 void do_el0_sync(struct thread *, struct trapframe *);
78 void do_el0_error(struct trapframe *);
79 void do_serror(struct trapframe *);
80 void unhandled_exception(struct trapframe *);
82 static void print_registers(struct trapframe *frame);
84 int (*dtrace_invop_jump_addr)(struct trapframe *);
86 typedef void (abort_handler)(struct thread *, struct trapframe *, uint64_t,
89 static abort_handler align_abort;
90 static abort_handler data_abort;
92 static abort_handler *abort_handlers[] = {
93 [ISS_DATA_DFSC_TF_L0] = data_abort,
94 [ISS_DATA_DFSC_TF_L1] = data_abort,
95 [ISS_DATA_DFSC_TF_L2] = data_abort,
96 [ISS_DATA_DFSC_TF_L3] = data_abort,
97 [ISS_DATA_DFSC_AFF_L1] = data_abort,
98 [ISS_DATA_DFSC_AFF_L2] = data_abort,
99 [ISS_DATA_DFSC_AFF_L3] = data_abort,
100 [ISS_DATA_DFSC_PF_L1] = data_abort,
101 [ISS_DATA_DFSC_PF_L2] = data_abort,
102 [ISS_DATA_DFSC_PF_L3] = data_abort,
103 [ISS_DATA_DFSC_ALIGN] = align_abort,
107 call_trapsignal(struct thread *td, int sig, int code, void *addr, int trapno)
111 ksiginfo_init_trap(&ksi);
115 ksi.ksi_trapno = trapno;
116 trapsignal(td, &ksi);
120 cpu_fetch_syscall_args(struct thread *td)
124 struct syscall_args *sa;
129 ap = td->td_frame->tf_x;
132 sa->code = td->td_frame->tf_x[8];
134 if (sa->code == SYS_syscall || sa->code == SYS___syscall) {
139 if (sa->code >= p->p_sysent->sv_size)
140 sa->callp = &p->p_sysent->sv_table[0];
142 sa->callp = &p->p_sysent->sv_table[sa->code];
144 sa->narg = sa->callp->sy_narg;
145 memcpy(sa->args, ap, nap * sizeof(register_t));
147 panic("ARM64TODO: Could we have more than 8 args?");
149 td->td_retval[0] = 0;
150 td->td_retval[1] = 0;
155 #include "../../kern/subr_syscall.c"
158 svc_handler(struct thread *td, struct trapframe *frame)
161 if ((frame->tf_esr & ESR_ELx_ISS_MASK) == 0) {
165 call_trapsignal(td, SIGILL, ILL_ILLOPN, (void *)frame->tf_elr,
166 ESR_ELx_EXCEPTION(frame->tf_esr));
172 align_abort(struct thread *td, struct trapframe *frame, uint64_t esr,
173 uint64_t far, int lower)
176 print_registers(frame);
177 printf(" far: %16lx\n", far);
178 printf(" esr: %.8lx\n", esr);
179 panic("Misaligned access from kernel space!");
182 call_trapsignal(td, SIGBUS, BUS_ADRALN, (void *)frame->tf_elr,
183 ESR_ELx_EXCEPTION(frame->tf_esr));
188 data_abort(struct thread *td, struct trapframe *frame, uint64_t esr,
189 uint64_t far, int lower)
195 int error, sig, ucode;
201 * According to the ARMv8-A rev. A.g, B2.10.5 "Load-Exclusive
202 * and Store-Exclusive instruction usage restrictions", state
203 * of the exclusive monitors after data abort exception is unknown.
217 map = &p->p_vmspace->vm_map;
221 /* The top bit tells us which range to use */
222 if (far >= VM_MAXUSER_ADDRESS) {
225 map = &p->p_vmspace->vm_map;
232 * Try to handle translation, access flag, and permission faults.
233 * Translation faults may occur as a result of the required
234 * break-before-make sequence used when promoting or demoting
235 * superpages. Such faults must not occur while holding the pmap lock,
236 * or pmap_fault() will recurse on that lock.
238 if ((lower || map == kernel_map || pcb->pcb_onfault != 0) &&
239 pmap_fault(map->pmap, esr, far) == KERN_SUCCESS)
242 KASSERT(td->td_md.md_spinlock_count == 0,
243 ("data abort with spinlock held"));
244 if (td->td_critnest != 0 || WITNESS_CHECK(WARN_SLEEPOK |
245 WARN_GIANTOK, NULL, "Kernel page fault") != 0) {
246 print_registers(frame);
247 printf(" far: %16lx\n", far);
248 printf(" esr: %.8lx\n", esr);
249 panic("data abort in critical section or under mutex");
252 switch (ESR_ELx_EXCEPTION(esr)) {
253 case EXCP_INSN_ABORT:
254 case EXCP_INSN_ABORT_L:
255 ftype = VM_PROT_EXECUTE;
258 ftype = (esr & ISS_DATA_WnR) == 0 ? VM_PROT_READ :
259 VM_PROT_READ | VM_PROT_WRITE;
263 /* Fault in the page. */
264 error = vm_fault_trap(map, far, ftype, VM_FAULT_NORMAL, &sig, &ucode);
265 if (error != KERN_SUCCESS) {
267 call_trapsignal(td, sig, ucode, (void *)far,
268 ESR_ELx_EXCEPTION(esr));
270 if (td->td_intr_nesting_level == 0 &&
271 pcb->pcb_onfault != 0) {
272 frame->tf_x[0] = error;
273 frame->tf_elr = pcb->pcb_onfault;
277 printf("Fatal data abort:\n");
278 print_registers(frame);
279 printf(" far: %16lx\n", far);
280 printf(" esr: %.8lx\n", esr);
283 if (debugger_on_trap) {
284 kdb_why = KDB_WHY_TRAP;
285 handled = kdb_trap(ESR_ELx_EXCEPTION(esr), 0,
287 kdb_why = KDB_WHY_UNSET;
292 panic("vm_fault failed: %lx", frame->tf_elr);
301 print_registers(struct trapframe *frame)
305 for (reg = 0; reg < nitems(frame->tf_x); reg++) {
306 printf(" %sx%d: %16lx\n", (reg < 10) ? " " : "", reg,
309 printf(" sp: %16lx\n", frame->tf_sp);
310 printf(" lr: %16lx\n", frame->tf_lr);
311 printf(" elr: %16lx\n", frame->tf_elr);
312 printf("spsr: %8x\n", frame->tf_spsr);
316 do_el1h_sync(struct thread *td, struct trapframe *frame)
318 struct trapframe *oframe;
323 /* Read the esr register to get the exception details */
325 exception = ESR_ELx_EXCEPTION(esr);
328 if (dtrace_trap_func != NULL && (*dtrace_trap_func)(frame, exception))
333 "do_el1_sync: curthread: %p, esr %lx, elr: %lx, frame: %p", td,
334 esr, frame->tf_elr, frame);
336 oframe = td->td_frame;
340 case EXCP_WATCHPT_EL1:
341 case EXCP_SOFTSTP_EL1:
344 td->td_frame = frame;
352 if ((td->td_pcb->pcb_fpflags & PCB_FP_KERN) != 0) {
357 print_registers(frame);
358 printf(" esr: %.8lx\n", esr);
359 panic("VFP exception in the kernel");
362 case EXCP_INSN_ABORT:
363 case EXCP_DATA_ABORT:
364 far = READ_SPECIALREG(far_el1);
365 dfsc = esr & ISS_DATA_DFSC_MASK;
366 if (dfsc < nitems(abort_handlers) &&
367 abort_handlers[dfsc] != NULL) {
368 abort_handlers[dfsc](td, frame, esr, far, 0);
370 print_registers(frame);
371 printf(" far: %16lx\n", far);
372 printf(" esr: %.8lx\n", esr);
373 panic("Unhandled EL1 %s abort: %x",
374 exception == EXCP_INSN_ABORT ? "instruction" :
380 if ((esr & ESR_ELx_ISS_MASK) == 0x40d && \
381 dtrace_invop_jump_addr != 0) {
382 dtrace_invop_jump_addr(frame);
387 kdb_trap(exception, 0,
388 (td->td_frame != NULL) ? td->td_frame : frame);
390 panic("No debugger in kernel.\n");
394 case EXCP_WATCHPT_EL1:
395 case EXCP_SOFTSTP_EL1:
397 kdb_trap(exception, 0,
398 (td->td_frame != NULL) ? td->td_frame : frame);
400 panic("No debugger in kernel.\n");
404 if (undef_insn(1, frame))
408 print_registers(frame);
409 printf(" far: %16lx\n", READ_SPECIALREG(far_el1));
410 panic("Unknown kernel exception %x esr_el1 %lx\n", exception,
414 td->td_frame = oframe;
418 do_el0_sync(struct thread *td, struct trapframe *frame)
420 pcpu_bp_harden bp_harden;
425 /* Check we have a sane environment when entering from userland */
426 KASSERT((uintptr_t)get_pcpu() >= VM_MIN_KERNEL_ADDRESS,
427 ("Invalid pcpu address from userland: %p (tpidr %lx)",
428 get_pcpu(), READ_SPECIALREG(tpidr_el1)));
431 exception = ESR_ELx_EXCEPTION(esr);
433 case EXCP_INSN_ABORT_L:
434 far = READ_SPECIALREG(far_el1);
437 * Userspace may be trying to train the branch predictor to
438 * attack the kernel. If we are on a CPU affected by this
439 * call the handler to clear the branch predictor state.
441 if (far > VM_MAXUSER_ADDRESS) {
442 bp_harden = PCPU_GET(bp_harden);
443 if (bp_harden != NULL)
448 case EXCP_DATA_ABORT_L:
449 case EXCP_DATA_ABORT:
450 far = READ_SPECIALREG(far_el1);
456 "do_el0_sync: curthread: %p, esr %lx, elr: %lx, frame: %p", td, esr,
457 frame->tf_elr, frame);
465 panic("VFP exception in userland");
470 svc_handler(td, frame);
472 case EXCP_INSN_ABORT_L:
473 case EXCP_DATA_ABORT_L:
474 case EXCP_DATA_ABORT:
475 dfsc = esr & ISS_DATA_DFSC_MASK;
476 if (dfsc < nitems(abort_handlers) &&
477 abort_handlers[dfsc] != NULL)
478 abort_handlers[dfsc](td, frame, esr, far, 1);
480 print_registers(frame);
481 printf(" far: %16lx\n", far);
482 printf(" esr: %.8lx\n", esr);
483 panic("Unhandled EL0 %s abort: %x",
484 exception == EXCP_INSN_ABORT_L ? "instruction" :
489 if (!undef_insn(0, frame))
490 call_trapsignal(td, SIGILL, ILL_ILLTRP, (void *)far,
495 call_trapsignal(td, SIGBUS, BUS_ADRALN, (void *)frame->tf_sp,
500 call_trapsignal(td, SIGBUS, BUS_ADRALN, (void *)frame->tf_elr,
506 call_trapsignal(td, SIGTRAP, TRAP_BRKPT, (void *)frame->tf_elr,
511 call_trapsignal(td, SIGILL, ILL_PRVOPC, (void *)frame->tf_elr,
515 case EXCP_SOFTSTP_EL0:
516 td->td_frame->tf_spsr &= ~PSR_SS;
517 td->td_pcb->pcb_flags &= ~PCB_SINGLE_STEP;
518 WRITE_SPECIALREG(mdscr_el1,
519 READ_SPECIALREG(mdscr_el1) & ~DBG_MDSCR_SS);
520 call_trapsignal(td, SIGTRAP, TRAP_TRACE,
521 (void *)frame->tf_elr, exception);
525 call_trapsignal(td, SIGBUS, BUS_OBJERR, (void *)frame->tf_elr,
531 KASSERT((td->td_pcb->pcb_fpflags & ~PCB_FP_USERMASK) == 0,
532 ("Kernel VFP flags set while entering userspace"));
534 td->td_pcb->pcb_fpusaved == &td->td_pcb->pcb_fpustate,
535 ("Kernel VFP state in use when entering userspace"));
539 * TODO: We will need to handle these later when we support ARMv8.2 RAS.
542 do_serror(struct trapframe *frame)
546 far = READ_SPECIALREG(far_el1);
549 print_registers(frame);
550 printf(" far: %16lx\n", far);
551 printf(" esr: %.8lx\n", esr);
552 panic("Unhandled System Error");
556 unhandled_exception(struct trapframe *frame)
560 far = READ_SPECIALREG(far_el1);
563 print_registers(frame);
564 printf(" far: %16lx\n", far);
565 printf(" esr: %.8lx\n", esr);
566 panic("Unhandled exception");