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 (p->p_sysent->sv_mask)
119 sa->code &= p->p_sysent->sv_mask;
120 if (sa->code >= p->p_sysent->sv_size)
121 sa->callp = &p->p_sysent->sv_table[0];
123 sa->callp = &p->p_sysent->sv_table[sa->code];
125 sa->narg = sa->callp->sy_narg;
126 memcpy(sa->args, ap, nap * sizeof(register_t));
128 panic("ARM64TODO: Could we have more than 8 args?");
130 td->td_retval[0] = 0;
131 td->td_retval[1] = 0;
136 #include "../../kern/subr_syscall.c"
139 svc_handler(struct thread *td, struct trapframe *frame)
143 if ((frame->tf_esr & ESR_ELx_ISS_MASK) == 0) {
144 error = syscallenter(td);
145 syscallret(td, error);
147 call_trapsignal(td, SIGILL, ILL_ILLOPN, (void *)frame->tf_elr);
153 data_abort(struct thread *td, struct trapframe *frame, uint64_t esr,
154 uint64_t far, int lower, int exec)
161 int error, sig, ucode;
167 * According to the ARMv8-A rev. A.g, B2.10.5 "Load-Exclusive
168 * and Store-Exclusive instruction usage restrictions", state
169 * of the exclusive monitors after data abort exception is unknown.
183 map = &p->p_vmspace->vm_map;
185 /* The top bit tells us which range to use */
186 if (far >= VM_MAXUSER_ADDRESS) {
189 map = &p->p_vmspace->vm_map;
196 * Try to handle translation, access flag, and permission faults.
197 * Translation faults may occur as a result of the required
198 * break-before-make sequence used when promoting or demoting
199 * superpages. Such faults must not occur while holding the pmap lock,
200 * or pmap_fault() will recurse on that lock.
202 if ((lower || map == kernel_map || pcb->pcb_onfault != 0) &&
203 pmap_fault(map->pmap, esr, far) == KERN_SUCCESS)
206 KASSERT(td->td_md.md_spinlock_count == 0,
207 ("data abort with spinlock held"));
208 if (td->td_critnest != 0 || WITNESS_CHECK(WARN_SLEEPOK |
209 WARN_GIANTOK, NULL, "Kernel page fault") != 0) {
210 print_registers(frame);
211 printf(" far: %16lx\n", far);
212 printf(" esr: %.8lx\n", esr);
213 panic("data abort in critical section or under mutex");
216 va = trunc_page(far);
218 ftype = VM_PROT_EXECUTE;
220 ftype = (esr & ISS_DATA_WnR) == 0 ? VM_PROT_READ :
221 VM_PROT_READ | VM_PROT_WRITE;
223 /* Fault in the page. */
224 error = vm_fault(map, va, ftype, VM_FAULT_NORMAL);
225 if (error != KERN_SUCCESS) {
228 if (error == KERN_PROTECTION_FAILURE)
232 call_trapsignal(td, sig, ucode, (void *)far);
234 if (td->td_intr_nesting_level == 0 &&
235 pcb->pcb_onfault != 0) {
236 frame->tf_x[0] = error;
237 frame->tf_elr = pcb->pcb_onfault;
241 printf("Fatal data abort:\n");
242 print_registers(frame);
243 printf(" far: %16lx\n", far);
244 printf(" esr: %.8lx\n", esr);
247 if (debugger_on_trap) {
248 kdb_why = KDB_WHY_TRAP;
249 handled = kdb_trap(ESR_ELx_EXCEPTION(esr), 0,
251 kdb_why = KDB_WHY_UNSET;
256 panic("vm_fault failed: %lx", frame->tf_elr);
265 print_registers(struct trapframe *frame)
269 for (reg = 0; reg < nitems(frame->tf_x); reg++) {
270 printf(" %sx%d: %16lx\n", (reg < 10) ? " " : "", reg,
273 printf(" sp: %16lx\n", frame->tf_sp);
274 printf(" lr: %16lx\n", frame->tf_lr);
275 printf(" elr: %16lx\n", frame->tf_elr);
276 printf("spsr: %8x\n", frame->tf_spsr);
280 do_el1h_sync(struct thread *td, struct trapframe *frame)
282 struct trapframe *oframe;
286 /* Read the esr register to get the exception details */
288 exception = ESR_ELx_EXCEPTION(esr);
291 if (dtrace_trap_func != NULL && (*dtrace_trap_func)(frame, exception))
296 "do_el1_sync: curthread: %p, esr %lx, elr: %lx, frame: %p", td,
297 esr, frame->tf_elr, frame);
299 oframe = td->td_frame;
303 case EXCP_WATCHPT_EL1:
304 case EXCP_SOFTSTP_EL1:
307 td->td_frame = frame;
315 if ((td->td_pcb->pcb_fpflags & PCB_FP_KERN) != 0) {
320 print_registers(frame);
321 printf(" esr: %.8lx\n", esr);
322 panic("VFP exception in the kernel");
325 case EXCP_INSN_ABORT:
326 case EXCP_DATA_ABORT:
327 far = READ_SPECIALREG(far_el1);
329 data_abort(td, frame, esr, far, 0,
330 exception == EXCP_INSN_ABORT);
334 if ((esr & ESR_ELx_ISS_MASK) == 0x40d && \
335 dtrace_invop_jump_addr != 0) {
336 dtrace_invop_jump_addr(frame);
341 kdb_trap(exception, 0,
342 (td->td_frame != NULL) ? td->td_frame : frame);
344 panic("No debugger in kernel.\n");
348 case EXCP_WATCHPT_EL1:
349 case EXCP_SOFTSTP_EL1:
351 kdb_trap(exception, 0,
352 (td->td_frame != NULL) ? td->td_frame : frame);
354 panic("No debugger in kernel.\n");
358 if (undef_insn(1, frame))
362 print_registers(frame);
363 panic("Unknown kernel exception %x esr_el1 %lx\n", exception,
367 td->td_frame = oframe;
371 do_el0_sync(struct thread *td, struct trapframe *frame)
373 pcpu_bp_harden bp_harden;
377 /* Check we have a sane environment when entering from userland */
378 KASSERT((uintptr_t)get_pcpu() >= VM_MIN_KERNEL_ADDRESS,
379 ("Invalid pcpu address from userland: %p (tpidr %lx)",
380 get_pcpu(), READ_SPECIALREG(tpidr_el1)));
383 exception = ESR_ELx_EXCEPTION(esr);
385 case EXCP_INSN_ABORT_L:
386 far = READ_SPECIALREG(far_el1);
389 * Userspace may be trying to train the branch predictor to
390 * attack the kernel. If we are on a CPU affected by this
391 * call the handler to clear the branch predictor state.
393 if (far > VM_MAXUSER_ADDRESS) {
394 bp_harden = PCPU_GET(bp_harden);
395 if (bp_harden != NULL)
400 case EXCP_DATA_ABORT_L:
401 case EXCP_DATA_ABORT:
402 far = READ_SPECIALREG(far_el1);
408 "do_el0_sync: curthread: %p, esr %lx, elr: %lx, frame: %p", td, esr,
409 frame->tf_elr, frame);
417 panic("VFP exception in userland");
422 svc_handler(td, frame);
424 case EXCP_INSN_ABORT_L:
425 case EXCP_DATA_ABORT_L:
426 case EXCP_DATA_ABORT:
427 data_abort(td, frame, esr, far, 1,
428 exception == EXCP_INSN_ABORT_L);
431 if (!undef_insn(0, frame))
432 call_trapsignal(td, SIGILL, ILL_ILLTRP, (void *)far);
436 call_trapsignal(td, SIGBUS, BUS_ADRALN, (void *)frame->tf_sp);
440 call_trapsignal(td, SIGBUS, BUS_ADRALN, (void *)frame->tf_elr);
444 call_trapsignal(td, SIGTRAP, TRAP_BRKPT, (void *)frame->tf_elr);
448 call_trapsignal(td, SIGILL, ILL_PRVOPC, (void *)frame->tf_elr);
451 case EXCP_SOFTSTP_EL0:
452 td->td_frame->tf_spsr &= ~PSR_SS;
453 td->td_pcb->pcb_flags &= ~PCB_SINGLE_STEP;
454 WRITE_SPECIALREG(MDSCR_EL1,
455 READ_SPECIALREG(MDSCR_EL1) & ~DBG_MDSCR_SS);
456 call_trapsignal(td, SIGTRAP, TRAP_TRACE,
457 (void *)frame->tf_elr);
461 call_trapsignal(td, SIGBUS, BUS_OBJERR, (void *)frame->tf_elr);
466 KASSERT((td->td_pcb->pcb_fpflags & ~PCB_FP_USERMASK) == 0,
467 ("Kernel VFP flags set while entering userspace"));
469 td->td_pcb->pcb_fpusaved == &td->td_pcb->pcb_fpustate,
470 ("Kernel VFP state in use when entering userspace"));
474 * TODO: We will need to handle these later when we support ARMv8.2 RAS.
477 do_serror(struct trapframe *frame)
481 far = READ_SPECIALREG(far_el1);
484 print_registers(frame);
485 printf(" far: %16lx\n", far);
486 printf(" esr: %.8lx\n", esr);
487 panic("Unhandled System Error");
491 unhandled_exception(struct trapframe *frame)
495 far = READ_SPECIALREG(far_el1);
498 print_registers(frame);
499 printf(" far: %16lx\n", far);
500 printf(" esr: %.8lx\n", esr);
501 panic("Unhandled exception");