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>
35 #include <sys/mutex.h>
36 #include <sys/pioctl.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 *);
87 call_trapsignal(struct thread *td, int sig, int code, void *addr)
91 ksiginfo_init_trap(&ksi);
99 cpu_fetch_syscall_args(struct thread *td)
103 struct syscall_args *sa;
108 ap = td->td_frame->tf_x;
111 sa->code = td->td_frame->tf_x[8];
113 if (sa->code == SYS_syscall || sa->code == SYS___syscall) {
118 if (sa->code >= p->p_sysent->sv_size)
119 sa->callp = &p->p_sysent->sv_table[0];
121 sa->callp = &p->p_sysent->sv_table[sa->code];
123 sa->narg = sa->callp->sy_narg;
124 memcpy(sa->args, ap, nap * sizeof(register_t));
126 panic("ARM64TODO: Could we have more than 8 args?");
128 td->td_retval[0] = 0;
129 td->td_retval[1] = 0;
134 #include "../../kern/subr_syscall.c"
137 svc_handler(struct thread *td, struct trapframe *frame)
141 if ((frame->tf_esr & ESR_ELx_ISS_MASK) == 0) {
142 error = syscallenter(td);
143 syscallret(td, error);
145 call_trapsignal(td, SIGILL, ILL_ILLOPN, (void *)frame->tf_elr);
151 data_abort(struct thread *td, struct trapframe *frame, uint64_t esr,
152 uint64_t far, int lower)
159 int error, sig, ucode;
165 * According to the ARMv8-A rev. A.g, B2.10.5 "Load-Exclusive
166 * and Store-Exclusive instruction usage restrictions", state
167 * of the exclusive monitors after data abort exception is unknown.
181 map = &p->p_vmspace->vm_map;
183 /* The top bit tells us which range to use */
184 if (far >= VM_MAXUSER_ADDRESS) {
187 map = &p->p_vmspace->vm_map;
194 * The call to pmap_fault can be dangerous when coming from the
195 * kernel as it may be not be able to lock the pmap to check if
196 * the address is now valid. Because of this we filter the cases
197 * when we are not going to see superpage activity.
201 * We may fault in a DMAP region due to a superpage being
202 * unmapped when the access took place.
204 if (map == kernel_map && !VIRT_IN_DMAP(far))
207 * We can also fault in the userspace handling functions,
208 * e.g. copyin. In these cases we will have set a fault
209 * handler so we can check if this is set before calling
212 if (map != kernel_map && pcb->pcb_onfault == 0)
216 if (pmap_fault(map->pmap, esr, far) == KERN_SUCCESS)
220 KASSERT(td->td_md.md_spinlock_count == 0,
221 ("data abort with spinlock held"));
222 if (td->td_critnest != 0 || WITNESS_CHECK(WARN_SLEEPOK |
223 WARN_GIANTOK, NULL, "Kernel page fault") != 0) {
224 print_registers(frame);
225 printf(" far: %16lx\n", far);
226 printf(" esr: %.8lx\n", esr);
227 panic("data abort in critical section or under mutex");
230 va = trunc_page(far);
231 ftype = ((esr >> 6) & 1) ? VM_PROT_READ | VM_PROT_WRITE : VM_PROT_READ;
233 /* Fault in the page. */
234 error = vm_fault(map, va, ftype, VM_FAULT_NORMAL);
235 if (error != KERN_SUCCESS) {
238 if (error == KERN_PROTECTION_FAILURE)
242 call_trapsignal(td, sig, ucode, (void *)far);
244 if (td->td_intr_nesting_level == 0 &&
245 pcb->pcb_onfault != 0) {
246 frame->tf_x[0] = error;
247 frame->tf_elr = pcb->pcb_onfault;
251 printf("Fatal data abort:\n");
252 print_registers(frame);
253 printf(" far: %16lx\n", far);
254 printf(" esr: %.8lx\n", esr);
257 if (debugger_on_trap) {
258 kdb_why = KDB_WHY_TRAP;
259 handled = kdb_trap(ESR_ELx_EXCEPTION(esr), 0,
261 kdb_why = KDB_WHY_UNSET;
266 panic("vm_fault failed: %lx", frame->tf_elr);
275 print_registers(struct trapframe *frame)
279 for (reg = 0; reg < nitems(frame->tf_x); reg++) {
280 printf(" %sx%d: %16lx\n", (reg < 10) ? " " : "", reg,
283 printf(" sp: %16lx\n", frame->tf_sp);
284 printf(" lr: %16lx\n", frame->tf_lr);
285 printf(" elr: %16lx\n", frame->tf_elr);
286 printf("spsr: %8x\n", frame->tf_spsr);
290 do_el1h_sync(struct thread *td, struct trapframe *frame)
292 struct trapframe *oframe;
296 /* Read the esr register to get the exception details */
298 exception = ESR_ELx_EXCEPTION(esr);
301 if (dtrace_trap_func != NULL && (*dtrace_trap_func)(frame, exception))
306 "do_el1_sync: curthread: %p, esr %lx, elr: %lx, frame: %p", td,
307 esr, frame->tf_elr, frame);
309 oframe = td->td_frame;
313 case EXCP_WATCHPT_EL1:
314 case EXCP_SOFTSTP_EL1:
317 td->td_frame = frame;
325 if ((td->td_pcb->pcb_fpflags & PCB_FP_KERN) != 0) {
330 print_registers(frame);
331 printf(" esr: %.8lx\n", esr);
332 panic("VFP exception in the kernel");
335 case EXCP_INSN_ABORT:
336 case EXCP_DATA_ABORT:
337 far = READ_SPECIALREG(far_el1);
339 data_abort(td, frame, esr, far, 0);
343 if ((esr & ESR_ELx_ISS_MASK) == 0x40d && \
344 dtrace_invop_jump_addr != 0) {
345 dtrace_invop_jump_addr(frame);
350 kdb_trap(exception, 0,
351 (td->td_frame != NULL) ? td->td_frame : frame);
353 panic("No debugger in kernel.\n");
357 case EXCP_WATCHPT_EL1:
358 case EXCP_SOFTSTP_EL1:
360 kdb_trap(exception, 0,
361 (td->td_frame != NULL) ? td->td_frame : frame);
363 panic("No debugger in kernel.\n");
367 if (undef_insn(1, frame))
371 print_registers(frame);
372 panic("Unknown kernel exception %x esr_el1 %lx\n", exception,
376 td->td_frame = oframe;
380 do_el0_sync(struct thread *td, struct trapframe *frame)
382 pcpu_bp_harden bp_harden;
386 /* Check we have a sane environment when entering from userland */
387 KASSERT((uintptr_t)get_pcpu() >= VM_MIN_KERNEL_ADDRESS,
388 ("Invalid pcpu address from userland: %p (tpidr %lx)",
389 get_pcpu(), READ_SPECIALREG(tpidr_el1)));
392 exception = ESR_ELx_EXCEPTION(esr);
394 case EXCP_INSN_ABORT_L:
395 far = READ_SPECIALREG(far_el1);
398 * Userspace may be trying to train the branch predictor to
399 * attack the kernel. If we are on a CPU affected by this
400 * call the handler to clear the branch predictor state.
402 if (far > VM_MAXUSER_ADDRESS) {
403 bp_harden = PCPU_GET(bp_harden);
404 if (bp_harden != NULL)
409 case EXCP_DATA_ABORT_L:
410 case EXCP_DATA_ABORT:
411 far = READ_SPECIALREG(far_el1);
417 "do_el0_sync: curthread: %p, esr %lx, elr: %lx, frame: %p", td, esr,
418 frame->tf_elr, frame);
426 panic("VFP exception in userland");
431 svc_handler(td, frame);
433 case EXCP_INSN_ABORT_L:
434 case EXCP_DATA_ABORT_L:
435 case EXCP_DATA_ABORT:
436 data_abort(td, frame, esr, far, 1);
439 if (!undef_insn(0, frame))
440 call_trapsignal(td, SIGILL, ILL_ILLTRP, (void *)far);
444 call_trapsignal(td, SIGBUS, BUS_ADRALN, (void *)frame->tf_sp);
448 call_trapsignal(td, SIGBUS, BUS_ADRALN, (void *)frame->tf_elr);
452 call_trapsignal(td, SIGTRAP, TRAP_BRKPT, (void *)frame->tf_elr);
456 call_trapsignal(td, SIGILL, ILL_PRVOPC, (void *)frame->tf_elr);
459 case EXCP_SOFTSTP_EL0:
460 td->td_frame->tf_spsr &= ~PSR_SS;
461 td->td_pcb->pcb_flags &= ~PCB_SINGLE_STEP;
462 WRITE_SPECIALREG(MDSCR_EL1,
463 READ_SPECIALREG(MDSCR_EL1) & ~DBG_MDSCR_SS);
464 call_trapsignal(td, SIGTRAP, TRAP_TRACE,
465 (void *)frame->tf_elr);
469 call_trapsignal(td, SIGBUS, BUS_OBJERR, (void *)frame->tf_elr);
474 KASSERT((td->td_pcb->pcb_fpflags & ~PCB_FP_USERMASK) == 0,
475 ("Kernel VFP flags set while entering userspace"));
477 td->td_pcb->pcb_fpusaved == &td->td_pcb->pcb_fpustate,
478 ("Kernel VFP state in use when entering userspace"));
482 * TODO: We will need to handle these later when we support ARMv8.2 RAS.
485 do_serror(struct trapframe *frame)
489 far = READ_SPECIALREG(far_el1);
492 print_registers(frame);
493 printf(" far: %16lx\n", far);
494 printf(" esr: %.8lx\n", esr);
495 panic("Unhandled System Error");
499 unhandled_exception(struct trapframe *frame)
503 far = READ_SPECIALREG(far_el1);
506 print_registers(frame);
507 printf(" far: %16lx\n", far);
508 printf(" esr: %.8lx\n", esr);
509 panic("Unhandled exception");