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 *);
88 call_trapsignal(struct thread *td, int sig, int code, void *addr)
92 ksiginfo_init_trap(&ksi);
100 cpu_fetch_syscall_args(struct thread *td)
104 struct syscall_args *sa;
109 ap = td->td_frame->tf_x;
112 sa->code = td->td_frame->tf_x[8];
114 if (sa->code == SYS_syscall || sa->code == SYS___syscall) {
119 if (sa->code >= p->p_sysent->sv_size)
120 sa->callp = &p->p_sysent->sv_table[0];
122 sa->callp = &p->p_sysent->sv_table[sa->code];
124 sa->narg = sa->callp->sy_narg;
125 memcpy(sa->args, ap, nap * sizeof(register_t));
127 panic("ARM64TODO: Could we have more than 8 args?");
129 td->td_retval[0] = 0;
130 td->td_retval[1] = 0;
135 #include "../../kern/subr_syscall.c"
138 svc_handler(struct thread *td, struct trapframe *frame)
141 if ((frame->tf_esr & ESR_ELx_ISS_MASK) == 0) {
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, int exec)
158 int error, sig, ucode;
164 * According to the ARMv8-A rev. A.g, B2.10.5 "Load-Exclusive
165 * and Store-Exclusive instruction usage restrictions", state
166 * of the exclusive monitors after data abort exception is unknown.
180 map = &p->p_vmspace->vm_map;
182 /* The top bit tells us which range to use */
183 if (far >= VM_MAXUSER_ADDRESS) {
186 map = &p->p_vmspace->vm_map;
193 * Try to handle translation, access flag, and permission faults.
194 * Translation faults may occur as a result of the required
195 * break-before-make sequence used when promoting or demoting
196 * superpages. Such faults must not occur while holding the pmap lock,
197 * or pmap_fault() will recurse on that lock.
199 if ((lower || map == kernel_map || pcb->pcb_onfault != 0) &&
200 pmap_fault(map->pmap, esr, far) == KERN_SUCCESS)
203 KASSERT(td->td_md.md_spinlock_count == 0,
204 ("data abort with spinlock held"));
205 if (td->td_critnest != 0 || WITNESS_CHECK(WARN_SLEEPOK |
206 WARN_GIANTOK, NULL, "Kernel page fault") != 0) {
207 print_registers(frame);
208 printf(" far: %16lx\n", far);
209 printf(" esr: %.8lx\n", esr);
210 panic("data abort in critical section or under mutex");
214 ftype = VM_PROT_EXECUTE;
216 ftype = (esr & ISS_DATA_WnR) == 0 ? VM_PROT_READ :
217 VM_PROT_READ | VM_PROT_WRITE;
219 /* Fault in the page. */
220 error = vm_fault_trap(map, far, ftype, VM_FAULT_NORMAL, &sig, &ucode);
221 if (error != KERN_SUCCESS) {
223 call_trapsignal(td, sig, ucode, (void *)far);
225 if (td->td_intr_nesting_level == 0 &&
226 pcb->pcb_onfault != 0) {
227 frame->tf_x[0] = error;
228 frame->tf_elr = pcb->pcb_onfault;
232 printf("Fatal data abort:\n");
233 print_registers(frame);
234 printf(" far: %16lx\n", far);
235 printf(" esr: %.8lx\n", esr);
238 if (debugger_on_trap) {
239 kdb_why = KDB_WHY_TRAP;
240 handled = kdb_trap(ESR_ELx_EXCEPTION(esr), 0,
242 kdb_why = KDB_WHY_UNSET;
247 panic("vm_fault failed: %lx", frame->tf_elr);
256 print_registers(struct trapframe *frame)
260 for (reg = 0; reg < nitems(frame->tf_x); reg++) {
261 printf(" %sx%d: %16lx\n", (reg < 10) ? " " : "", reg,
264 printf(" sp: %16lx\n", frame->tf_sp);
265 printf(" lr: %16lx\n", frame->tf_lr);
266 printf(" elr: %16lx\n", frame->tf_elr);
267 printf("spsr: %8x\n", frame->tf_spsr);
271 do_el1h_sync(struct thread *td, struct trapframe *frame)
273 struct trapframe *oframe;
277 /* Read the esr register to get the exception details */
279 exception = ESR_ELx_EXCEPTION(esr);
282 if (dtrace_trap_func != NULL && (*dtrace_trap_func)(frame, exception))
287 "do_el1_sync: curthread: %p, esr %lx, elr: %lx, frame: %p", td,
288 esr, frame->tf_elr, frame);
290 oframe = td->td_frame;
294 case EXCP_WATCHPT_EL1:
295 case EXCP_SOFTSTP_EL1:
298 td->td_frame = frame;
306 if ((td->td_pcb->pcb_fpflags & PCB_FP_KERN) != 0) {
311 print_registers(frame);
312 printf(" esr: %.8lx\n", esr);
313 panic("VFP exception in the kernel");
316 case EXCP_INSN_ABORT:
317 case EXCP_DATA_ABORT:
318 far = READ_SPECIALREG(far_el1);
320 data_abort(td, frame, esr, far, 0,
321 exception == EXCP_INSN_ABORT);
325 if ((esr & ESR_ELx_ISS_MASK) == 0x40d && \
326 dtrace_invop_jump_addr != 0) {
327 dtrace_invop_jump_addr(frame);
332 kdb_trap(exception, 0,
333 (td->td_frame != NULL) ? td->td_frame : frame);
335 panic("No debugger in kernel.\n");
339 case EXCP_WATCHPT_EL1:
340 case EXCP_SOFTSTP_EL1:
342 kdb_trap(exception, 0,
343 (td->td_frame != NULL) ? td->td_frame : frame);
345 panic("No debugger in kernel.\n");
349 if (undef_insn(1, frame))
353 print_registers(frame);
354 panic("Unknown kernel exception %x esr_el1 %lx\n", exception,
358 td->td_frame = oframe;
362 do_el0_sync(struct thread *td, struct trapframe *frame)
364 pcpu_bp_harden bp_harden;
368 /* Check we have a sane environment when entering from userland */
369 KASSERT((uintptr_t)get_pcpu() >= VM_MIN_KERNEL_ADDRESS,
370 ("Invalid pcpu address from userland: %p (tpidr %lx)",
371 get_pcpu(), READ_SPECIALREG(tpidr_el1)));
374 exception = ESR_ELx_EXCEPTION(esr);
376 case EXCP_INSN_ABORT_L:
377 far = READ_SPECIALREG(far_el1);
380 * Userspace may be trying to train the branch predictor to
381 * attack the kernel. If we are on a CPU affected by this
382 * call the handler to clear the branch predictor state.
384 if (far > VM_MAXUSER_ADDRESS) {
385 bp_harden = PCPU_GET(bp_harden);
386 if (bp_harden != NULL)
391 case EXCP_DATA_ABORT_L:
392 case EXCP_DATA_ABORT:
393 far = READ_SPECIALREG(far_el1);
399 "do_el0_sync: curthread: %p, esr %lx, elr: %lx, frame: %p", td, esr,
400 frame->tf_elr, frame);
408 panic("VFP exception in userland");
413 svc_handler(td, frame);
415 case EXCP_INSN_ABORT_L:
416 case EXCP_DATA_ABORT_L:
417 case EXCP_DATA_ABORT:
418 data_abort(td, frame, esr, far, 1,
419 exception == EXCP_INSN_ABORT_L);
422 if (!undef_insn(0, frame))
423 call_trapsignal(td, SIGILL, ILL_ILLTRP, (void *)far);
427 call_trapsignal(td, SIGBUS, BUS_ADRALN, (void *)frame->tf_sp);
431 call_trapsignal(td, SIGBUS, BUS_ADRALN, (void *)frame->tf_elr);
435 call_trapsignal(td, SIGTRAP, TRAP_BRKPT, (void *)frame->tf_elr);
439 call_trapsignal(td, SIGILL, ILL_PRVOPC, (void *)frame->tf_elr);
442 case EXCP_SOFTSTP_EL0:
443 td->td_frame->tf_spsr &= ~PSR_SS;
444 td->td_pcb->pcb_flags &= ~PCB_SINGLE_STEP;
445 WRITE_SPECIALREG(MDSCR_EL1,
446 READ_SPECIALREG(MDSCR_EL1) & ~DBG_MDSCR_SS);
447 call_trapsignal(td, SIGTRAP, TRAP_TRACE,
448 (void *)frame->tf_elr);
452 call_trapsignal(td, SIGBUS, BUS_OBJERR, (void *)frame->tf_elr);
457 KASSERT((td->td_pcb->pcb_fpflags & ~PCB_FP_USERMASK) == 0,
458 ("Kernel VFP flags set while entering userspace"));
460 td->td_pcb->pcb_fpusaved == &td->td_pcb->pcb_fpustate,
461 ("Kernel VFP state in use when entering userspace"));
465 * TODO: We will need to handle these later when we support ARMv8.2 RAS.
468 do_serror(struct trapframe *frame)
472 far = READ_SPECIALREG(far_el1);
475 print_registers(frame);
476 printf(" far: %16lx\n", far);
477 printf(" esr: %.8lx\n", esr);
478 panic("Unhandled System Error");
482 unhandled_exception(struct trapframe *frame)
486 far = READ_SPECIALREG(far_el1);
489 print_registers(frame);
490 printf(" far: %16lx\n", far);
491 printf(" esr: %.8lx\n", esr);
492 panic("Unhandled exception");