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>
37 #include <sys/pioctl.h>
39 #include <sys/ptrace.h>
40 #include <sys/syscall.h>
41 #include <sys/sysent.h>
48 #include <vm/vm_kern.h>
49 #include <vm/vm_map.h>
50 #include <vm/vm_param.h>
51 #include <vm/vm_extern.h>
53 #include <machine/frame.h>
54 #include <machine/pcb.h>
55 #include <machine/pcpu.h>
56 #include <machine/undefined.h>
59 #include <sys/dtrace_bsd.h>
63 #include <machine/vfp.h>
67 #include <machine/db_machdep.h>
71 #include <ddb/db_output.h>
74 extern register_t fsu_intr_fault;
76 /* Called from exception.S */
77 void do_el1h_sync(struct thread *, struct trapframe *);
78 void do_el0_sync(struct thread *, struct trapframe *);
79 void do_el0_error(struct trapframe *);
80 void do_serror(struct trapframe *);
81 void unhandled_exception(struct trapframe *);
83 static void print_registers(struct trapframe *frame);
85 int (*dtrace_invop_jump_addr)(struct trapframe *);
87 typedef void (abort_handler)(struct thread *, struct trapframe *, uint64_t,
90 static abort_handler align_abort;
91 static abort_handler data_abort;
93 static abort_handler *abort_handlers[] = {
94 [ISS_DATA_DFSC_TF_L0] = data_abort,
95 [ISS_DATA_DFSC_TF_L1] = data_abort,
96 [ISS_DATA_DFSC_TF_L2] = data_abort,
97 [ISS_DATA_DFSC_TF_L3] = data_abort,
98 [ISS_DATA_DFSC_AFF_L1] = data_abort,
99 [ISS_DATA_DFSC_AFF_L2] = data_abort,
100 [ISS_DATA_DFSC_AFF_L3] = data_abort,
101 [ISS_DATA_DFSC_PF_L1] = data_abort,
102 [ISS_DATA_DFSC_PF_L2] = data_abort,
103 [ISS_DATA_DFSC_PF_L3] = data_abort,
104 [ISS_DATA_DFSC_ALIGN] = align_abort,
108 call_trapsignal(struct thread *td, int sig, int code, void *addr)
112 ksiginfo_init_trap(&ksi);
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);
171 align_abort(struct thread *td, struct trapframe *frame, uint64_t esr,
172 uint64_t far, int lower)
175 panic("Misaligned access from kernel space!");
177 call_trapsignal(td, SIGBUS, BUS_ADRALN, (void *)frame->tf_elr);
182 data_abort(struct thread *td, struct trapframe *frame, uint64_t esr,
183 uint64_t far, int lower)
189 int error, sig, ucode;
195 * According to the ARMv8-A rev. A.g, B2.10.5 "Load-Exclusive
196 * and Store-Exclusive instruction usage restrictions", state
197 * of the exclusive monitors after data abort exception is unknown.
211 map = &p->p_vmspace->vm_map;
215 /* The top bit tells us which range to use */
216 if (far >= VM_MAXUSER_ADDRESS) {
219 map = &p->p_vmspace->vm_map;
226 * Try to handle translation, access flag, and permission faults.
227 * Translation faults may occur as a result of the required
228 * break-before-make sequence used when promoting or demoting
229 * superpages. Such faults must not occur while holding the pmap lock,
230 * or pmap_fault() will recurse on that lock.
232 if ((lower || map == kernel_map || pcb->pcb_onfault != 0) &&
233 pmap_fault(map->pmap, esr, far) == KERN_SUCCESS)
236 KASSERT(td->td_md.md_spinlock_count == 0,
237 ("data abort with spinlock held"));
238 if (td->td_critnest != 0 || WITNESS_CHECK(WARN_SLEEPOK |
239 WARN_GIANTOK, NULL, "Kernel page fault") != 0) {
240 print_registers(frame);
241 printf(" far: %16lx\n", far);
242 printf(" esr: %.8lx\n", esr);
243 panic("data abort in critical section or under mutex");
246 switch (ESR_ELx_EXCEPTION(esr)) {
247 case EXCP_INSN_ABORT:
248 case EXCP_INSN_ABORT_L:
249 ftype = VM_PROT_EXECUTE;
252 ftype = (esr & ISS_DATA_WnR) == 0 ? VM_PROT_READ :
253 VM_PROT_READ | VM_PROT_WRITE;
257 /* Fault in the page. */
258 error = vm_fault_trap(map, far, ftype, VM_FAULT_NORMAL, &sig, &ucode);
259 if (error != KERN_SUCCESS) {
261 call_trapsignal(td, sig, ucode, (void *)far);
263 if (td->td_intr_nesting_level == 0 &&
264 pcb->pcb_onfault != 0) {
265 frame->tf_x[0] = error;
266 frame->tf_elr = pcb->pcb_onfault;
270 printf("Fatal data abort:\n");
271 print_registers(frame);
272 printf(" far: %16lx\n", far);
273 printf(" esr: %.8lx\n", esr);
276 if (debugger_on_trap) {
277 kdb_why = KDB_WHY_TRAP;
278 handled = kdb_trap(ESR_ELx_EXCEPTION(esr), 0,
280 kdb_why = KDB_WHY_UNSET;
285 panic("vm_fault failed: %lx", frame->tf_elr);
294 print_registers(struct trapframe *frame)
298 for (reg = 0; reg < nitems(frame->tf_x); reg++) {
299 printf(" %sx%d: %16lx\n", (reg < 10) ? " " : "", reg,
302 printf(" sp: %16lx\n", frame->tf_sp);
303 printf(" lr: %16lx\n", frame->tf_lr);
304 printf(" elr: %16lx\n", frame->tf_elr);
305 printf("spsr: %8x\n", frame->tf_spsr);
309 do_el1h_sync(struct thread *td, struct trapframe *frame)
311 struct trapframe *oframe;
316 /* Read the esr register to get the exception details */
318 exception = ESR_ELx_EXCEPTION(esr);
321 if (dtrace_trap_func != NULL && (*dtrace_trap_func)(frame, exception))
326 "do_el1_sync: curthread: %p, esr %lx, elr: %lx, frame: %p", td,
327 esr, frame->tf_elr, frame);
329 oframe = td->td_frame;
333 case EXCP_WATCHPT_EL1:
334 case EXCP_SOFTSTP_EL1:
337 td->td_frame = frame;
345 if ((td->td_pcb->pcb_fpflags & PCB_FP_KERN) != 0) {
350 print_registers(frame);
351 printf(" esr: %.8lx\n", esr);
352 panic("VFP exception in the kernel");
355 case EXCP_INSN_ABORT:
356 case EXCP_DATA_ABORT:
357 far = READ_SPECIALREG(far_el1);
358 dfsc = esr & ISS_DATA_DFSC_MASK;
359 if (dfsc < nitems(abort_handlers) &&
360 abort_handlers[dfsc] != NULL) {
361 abort_handlers[dfsc](td, frame, esr, far, 0);
363 print_registers(frame);
364 printf(" far: %16lx\n", far);
365 panic("Unhandled EL1 %s abort: %x",
366 exception == EXCP_INSN_ABORT ? "instruction" :
372 if ((esr & ESR_ELx_ISS_MASK) == 0x40d && \
373 dtrace_invop_jump_addr != 0) {
374 dtrace_invop_jump_addr(frame);
379 kdb_trap(exception, 0,
380 (td->td_frame != NULL) ? td->td_frame : frame);
382 panic("No debugger in kernel.\n");
386 case EXCP_WATCHPT_EL1:
387 case EXCP_SOFTSTP_EL1:
389 kdb_trap(exception, 0,
390 (td->td_frame != NULL) ? td->td_frame : frame);
392 panic("No debugger in kernel.\n");
396 if (undef_insn(1, frame))
400 print_registers(frame);
401 panic("Unknown kernel exception %x esr_el1 %lx\n", exception,
405 td->td_frame = oframe;
409 do_el0_sync(struct thread *td, struct trapframe *frame)
411 pcpu_bp_harden bp_harden;
416 /* Check we have a sane environment when entering from userland */
417 KASSERT((uintptr_t)get_pcpu() >= VM_MIN_KERNEL_ADDRESS,
418 ("Invalid pcpu address from userland: %p (tpidr %lx)",
419 get_pcpu(), READ_SPECIALREG(tpidr_el1)));
422 exception = ESR_ELx_EXCEPTION(esr);
424 case EXCP_INSN_ABORT_L:
425 far = READ_SPECIALREG(far_el1);
428 * Userspace may be trying to train the branch predictor to
429 * attack the kernel. If we are on a CPU affected by this
430 * call the handler to clear the branch predictor state.
432 if (far > VM_MAXUSER_ADDRESS) {
433 bp_harden = PCPU_GET(bp_harden);
434 if (bp_harden != NULL)
439 case EXCP_DATA_ABORT_L:
440 case EXCP_DATA_ABORT:
441 far = READ_SPECIALREG(far_el1);
447 "do_el0_sync: curthread: %p, esr %lx, elr: %lx, frame: %p", td, esr,
448 frame->tf_elr, frame);
456 panic("VFP exception in userland");
461 svc_handler(td, frame);
463 case EXCP_INSN_ABORT_L:
464 case EXCP_DATA_ABORT_L:
465 case EXCP_DATA_ABORT:
466 dfsc = esr & ISS_DATA_DFSC_MASK;
467 if (dfsc < nitems(abort_handlers) &&
468 abort_handlers[dfsc] != NULL)
469 abort_handlers[dfsc](td, frame, esr, far, 1);
471 panic("Unhandled EL0 %s abort: %x",
472 exception == EXCP_INSN_ABORT_L ? "instruction" :
476 if (!undef_insn(0, frame))
477 call_trapsignal(td, SIGILL, ILL_ILLTRP, (void *)far);
481 call_trapsignal(td, SIGBUS, BUS_ADRALN, (void *)frame->tf_sp);
485 call_trapsignal(td, SIGBUS, BUS_ADRALN, (void *)frame->tf_elr);
490 call_trapsignal(td, SIGTRAP, TRAP_BRKPT, (void *)frame->tf_elr);
494 call_trapsignal(td, SIGILL, ILL_PRVOPC, (void *)frame->tf_elr);
497 case EXCP_SOFTSTP_EL0:
498 td->td_frame->tf_spsr &= ~PSR_SS;
499 td->td_pcb->pcb_flags &= ~PCB_SINGLE_STEP;
500 WRITE_SPECIALREG(mdscr_el1,
501 READ_SPECIALREG(mdscr_el1) & ~DBG_MDSCR_SS);
502 call_trapsignal(td, SIGTRAP, TRAP_TRACE,
503 (void *)frame->tf_elr);
507 call_trapsignal(td, SIGBUS, BUS_OBJERR, (void *)frame->tf_elr);
512 KASSERT((td->td_pcb->pcb_fpflags & ~PCB_FP_USERMASK) == 0,
513 ("Kernel VFP flags set while entering userspace"));
515 td->td_pcb->pcb_fpusaved == &td->td_pcb->pcb_fpustate,
516 ("Kernel VFP state in use when entering userspace"));
520 * TODO: We will need to handle these later when we support ARMv8.2 RAS.
523 do_serror(struct trapframe *frame)
527 far = READ_SPECIALREG(far_el1);
530 print_registers(frame);
531 printf(" far: %16lx\n", far);
532 printf(" esr: %.8lx\n", esr);
533 panic("Unhandled System Error");
537 unhandled_exception(struct trapframe *frame)
541 far = READ_SPECIALREG(far_el1);
544 print_registers(frame);
545 printf(" far: %16lx\n", far);
546 printf(" esr: %.8lx\n", esr);
547 panic("Unhandled exception");