1 /* $NetBSD: fault.c,v 1.45 2003/11/20 14:44:36 scw Exp $ */
4 * Copyright 2004 Olivier Houchard
5 * Copyright 2003 Wasabi Systems, Inc.
8 * Written by Steve C. Woodford for Wasabi Systems, Inc.
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 * 3. All advertising materials mentioning features or use of this software
19 * must display the following acknowledgement:
20 * This product includes software developed for the NetBSD Project by
21 * Wasabi Systems, Inc.
22 * 4. The name of Wasabi Systems, Inc. may not be used to endorse
23 * or promote products derived from this software without specific prior
26 * THIS SOFTWARE IS PROVIDED BY WASABI SYSTEMS, INC. ``AS IS'' AND
27 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
28 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
29 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL WASABI SYSTEMS, INC
30 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
31 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
32 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
33 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
34 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
35 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
36 * POSSIBILITY OF SUCH DAMAGE.
39 * Copyright (c) 1994-1997 Mark Brinicombe.
40 * Copyright (c) 1994 Brini.
41 * All rights reserved.
43 * This code is derived from software written for Brini by Mark Brinicombe
45 * Redistribution and use in source and binary forms, with or without
46 * modification, are permitted provided that the following conditions
48 * 1. Redistributions of source code must retain the above copyright
49 * notice, this list of conditions and the following disclaimer.
50 * 2. Redistributions in binary form must reproduce the above copyright
51 * notice, this list of conditions and the following disclaimer in the
52 * documentation and/or other materials provided with the distribution.
53 * 3. All advertising materials mentioning features or use of this software
54 * must display the following acknowledgement:
55 * This product includes software developed by Brini.
56 * 4. The name of the company nor the name of the author may be used to
57 * endorse or promote products derived from this software without specific
58 * prior written permission.
60 * THIS SOFTWARE IS PROVIDED BY BRINI ``AS IS'' AND ANY EXPRESS OR IMPLIED
61 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
62 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
63 * IN NO EVENT SHALL BRINI OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
64 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
65 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
66 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
67 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
68 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
69 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
72 * RiscBSD kernel project
82 #include "opt_ktrace.h"
84 #include <sys/cdefs.h>
85 __FBSDID("$FreeBSD$");
87 #include <sys/param.h>
88 #include <sys/systm.h>
90 #include <sys/kernel.h>
92 #include <sys/mutex.h>
93 #include <sys/syscall.h>
94 #include <sys/sysent.h>
95 #include <sys/signalvar.h>
99 #include <sys/ktrace.h>
101 #include <sys/ptrace.h>
102 #include <sys/pioctl.h>
106 #include <vm/vm_kern.h>
107 #include <vm/vm_map.h>
108 #include <vm/vm_extern.h>
110 #include <machine/cpuconf.h>
111 #include <machine/vmparam.h>
112 #include <machine/frame.h>
113 #include <machine/cpu.h>
114 #include <machine/intr.h>
115 #include <machine/pcb.h>
116 #include <machine/proc.h>
117 #include <machine/swi.h>
119 #include <security/audit/audit.h>
126 void swi_handler(trapframe_t *);
127 void undefinedinstruction(trapframe_t *);
129 #include <machine/disassem.h>
130 #include <machine/machdep.h>
132 extern char fusubailout[];
133 extern char *syscallnames[];
136 int last_fault_code; /* For the benefit of pmap_fault_fixup() */
139 #if defined(CPU_ARM7TDMI)
140 /* These CPUs may need data/prefetch abort fixups */
141 #define CPU_ABORT_FIXUP_REQUIRED
149 int (*func)(trapframe_t *, u_int, u_int, struct thread *, struct ksig *);
153 static int dab_fatal(trapframe_t *, u_int, u_int, struct thread *, struct ksig *);
154 static int dab_align(trapframe_t *, u_int, u_int, struct thread *, struct ksig *);
155 static int dab_buserr(trapframe_t *, u_int, u_int, struct thread *, struct ksig *);
157 static const struct data_abort data_aborts[] = {
158 {dab_fatal, "Vector Exception"},
159 {dab_align, "Alignment Fault 1"},
160 {dab_fatal, "Terminal Exception"},
161 {dab_align, "Alignment Fault 3"},
162 {dab_buserr, "External Linefetch Abort (S)"},
163 {NULL, "Translation Fault (S)"},
164 {dab_buserr, "External Linefetch Abort (P)"},
165 {NULL, "Translation Fault (P)"},
166 {dab_buserr, "External Non-Linefetch Abort (S)"},
167 {NULL, "Domain Fault (S)"},
168 {dab_buserr, "External Non-Linefetch Abort (P)"},
169 {NULL, "Domain Fault (P)"},
170 {dab_buserr, "External Translation Abort (L1)"},
171 {NULL, "Permission Fault (S)"},
172 {dab_buserr, "External Translation Abort (L2)"},
173 {NULL, "Permission Fault (P)"}
176 /* Determine if a fault came from user mode */
177 #define TRAP_USERMODE(tf) ((tf->tf_spsr & PSR_MODE) == PSR_USR32_MODE)
179 /* Determine if 'x' is a permission fault */
180 #define IS_PERMISSION_FAULT(x) \
181 (((1 << ((x) & FAULT_TYPE_MASK)) & \
182 ((1 << FAULT_PERM_P) | (1 << FAULT_PERM_S))) != 0)
185 call_trapsignal(struct thread *td, int sig, u_long code)
189 ksiginfo_init_trap(&ksi);
191 ksi.ksi_code = (int)code;
192 trapsignal(td, &ksi);
196 data_abort_fixup(trapframe_t *tf, u_int fsr, u_int far, struct thread *td, struct ksig *ksig)
198 #ifdef CPU_ABORT_FIXUP_REQUIRED
201 /* Call the cpu specific data abort fixup routine */
202 error = cpu_dataabt_fixup(tf);
203 if (__predict_true(error != ABORT_FIXUP_FAILED))
207 * Oops, couldn't fix up the instruction
209 printf("data_abort_fixup: fixup for %s mode data abort failed.\n",
210 TRAP_USERMODE(tf) ? "user" : "kernel");
211 printf("pc = 0x%08x, opcode 0x%08x, insn = ", tf->tf_pc,
212 *((u_int *)tf->tf_pc));
213 disassemble(tf->tf_pc);
215 /* Die now if this happened in kernel mode */
216 if (!TRAP_USERMODE(tf))
217 dab_fatal(tf, fsr, far, td, NULL, ksig);
221 return (ABORT_FIXUP_OK);
222 #endif /* CPU_ABORT_FIXUP_REQUIRED */
226 data_abort_handler(trapframe_t *tf)
231 u_int user, far, fsr;
240 /* Grab FAR/FSR before enabling interrupts */
241 far = cpu_faultaddress();
242 fsr = cpu_faultstatus();
244 printf("data abort: %p (from %p %p)\n", (void*)far, (void*)tf->tf_pc,
245 (void*)tf->tf_svc_lr);
248 /* Update vmmeter statistics */
256 PCPU_INC(cnt.v_trap);
257 /* Data abort came from user mode? */
258 user = TRAP_USERMODE(tf);
263 if (td->td_ucred != td->td_proc->p_ucred)
264 cred_update_thread(td);
267 /* Grab the current pcb */
269 /* Re-enable interrupts if they were enabled previously */
270 if (td->td_md.md_spinlock_count == 0) {
271 if (__predict_true(tf->tf_spsr & I32_bit) == 0)
272 enable_interrupts(I32_bit);
273 if (__predict_true(tf->tf_spsr & F32_bit) == 0)
274 enable_interrupts(F32_bit);
278 /* Invoke the appropriate handler, if necessary */
279 if (__predict_false(data_aborts[fsr & FAULT_TYPE_MASK].func != NULL)) {
280 if ((data_aborts[fsr & FAULT_TYPE_MASK].func)(tf, fsr, far,
288 * At this point, we're dealing with one of the following data aborts:
290 * FAULT_TRANS_S - Translation -- Section
291 * FAULT_TRANS_P - Translation -- Page
292 * FAULT_DOMAIN_S - Domain -- Section
293 * FAULT_DOMAIN_P - Domain -- Page
294 * FAULT_PERM_S - Permission -- Section
295 * FAULT_PERM_P - Permission -- Page
297 * These are the main virtual memory-related faults signalled by
301 /* fusubailout is used by [fs]uswintr to avoid page faulting */
302 if (__predict_false(pcb->pcb_onfault == fusubailout)) {
304 tf->tf_pc = (register_t)(intptr_t) pcb->pcb_onfault;
309 * Make sure the Program Counter is sane. We could fall foul of
310 * someone executing Thumb code, in which case the PC might not
311 * be word-aligned. This would cause a kernel alignment fault
312 * further down if we have to decode the current instruction.
313 * XXX: It would be nice to be able to support Thumb at some point.
315 if (__predict_false((tf->tf_pc & 3) != 0)) {
318 * Give the user an illegal instruction signal.
320 /* Deliver a SIGILL to the process */
327 * The kernel never executes Thumb code.
329 printf("\ndata_abort_fault: Misaligned Kernel-mode "
330 "Program Counter\n");
331 dab_fatal(tf, fsr, far, td, &ksig);
334 /* See if the cpu state needs to be fixed up */
335 switch (data_abort_fixup(tf, fsr, far, td, &ksig)) {
336 case ABORT_FIXUP_RETURN:
338 case ABORT_FIXUP_FAILED:
339 /* Deliver a SIGILL to the process */
347 va = trunc_page((vm_offset_t)far);
350 * It is only a kernel address space fault iff:
352 * 2. pcb_onfault not set or
353 * 3. pcb_onfault set and not LDRT/LDRBT/STRT/STRBT instruction.
355 if (user == 0 && (va >= VM_MIN_KERNEL_ADDRESS ||
356 (va < VM_MIN_ADDRESS && vector_page == ARM_VECTORS_LOW)) &&
357 __predict_true((pcb->pcb_onfault == NULL ||
358 (ReadWord(tf->tf_pc) & 0x05200000) != 0x04200000))) {
361 /* Was the fault due to the FPE/IPKDB ? */
362 if (__predict_false((tf->tf_spsr & PSR_MODE)==PSR_UND32_MODE)) {
365 * Force exit via userret()
366 * This is necessary as the FPE is an extension to
367 * userland that actually runs in a priveledged mode
368 * but uses USR mode permissions for its accesses.
371 ksig.signb = SIGSEGV;
376 map = &td->td_proc->p_vmspace->vm_map;
380 * We need to know whether the page should be mapped
381 * as R or R/W. The MMU does not give us the info as
382 * to whether the fault was caused by a read or a write.
384 * However, we know that a permission fault can only be
385 * the result of a write to a read-only location, so
386 * we can deal with those quickly.
388 * Otherwise we need to disassemble the instruction
389 * responsible to determine if it was a write.
391 if (IS_PERMISSION_FAULT(fsr)) {
392 ftype = VM_PROT_WRITE;
394 u_int insn = ReadWord(tf->tf_pc);
396 if (((insn & 0x0c100000) == 0x04000000) || /* STR/STRB */
397 ((insn & 0x0e1000b0) == 0x000000b0) || /* STRH/STRD */
398 ((insn & 0x0a100000) == 0x08000000)) /* STM/CDT */
400 ftype = VM_PROT_WRITE;
403 if ((insn & 0x0fb00ff0) == 0x01000090) /* SWP */
404 ftype = VM_PROT_READ | VM_PROT_WRITE;
406 ftype = VM_PROT_READ;
410 * See if the fault is as a result of ref/mod emulation,
411 * or domain mismatch.
414 last_fault_code = fsr;
416 if (pmap_fault_fixup(vmspace_pmap(td->td_proc->p_vmspace), va, ftype,
421 onfault = pcb->pcb_onfault;
422 pcb->pcb_onfault = NULL;
423 if (map != kernel_map) {
428 error = vm_fault(map, va, ftype, (ftype & VM_PROT_WRITE) ?
429 VM_FAULT_DIRTY : VM_FAULT_NORMAL);
430 pcb->pcb_onfault = onfault;
432 if (map != kernel_map) {
437 if (__predict_true(error == 0))
440 if (pcb->pcb_onfault) {
442 tf->tf_pc = (register_t)(intptr_t) pcb->pcb_onfault;
446 printf("\nvm_fault(%p, %x, %x, 0) -> %x\n", map, va, ftype,
448 dab_fatal(tf, fsr, far, td, &ksig);
452 if (error == ENOMEM) {
453 printf("VM: pid %d (%s), uid %d killed: "
454 "out of swap\n", td->td_proc->p_pid, td->td_name,
455 (td->td_proc->p_ucred) ?
456 td->td_proc->p_ucred->cr_uid : -1);
457 ksig.signb = SIGKILL;
459 ksig.signb = SIGSEGV;
463 call_trapsignal(td, ksig.signb, ksig.code);
465 /* If returning to user mode, make sure to invoke userret() */
471 * dab_fatal() handles the following data aborts:
473 * FAULT_WRTBUF_0 - Vector Exception
474 * FAULT_WRTBUF_1 - Terminal Exception
476 * We should never see these on a properly functioning system.
478 * This function is also called by the other handlers if they
479 * detect a fatal problem.
481 * Note: If 'l' is NULL, we assume we're dealing with a prefetch abort.
484 dab_fatal(trapframe_t *tf, u_int fsr, u_int far, struct thread *td, struct ksig *ksig)
488 mode = TRAP_USERMODE(tf) ? "user" : "kernel";
490 disable_interrupts(I32_bit|F32_bit);
492 printf("Fatal %s mode data abort: '%s'\n", mode,
493 data_aborts[fsr & FAULT_TYPE_MASK].desc);
494 printf("trapframe: %p\nFSR=%08x, FAR=", tf, fsr);
495 if ((fsr & FAULT_IMPRECISE) == 0)
496 printf("%08x, ", far);
499 printf("spsr=%08x\n", tf->tf_spsr);
501 printf("Fatal %s mode prefetch abort at 0x%08x\n",
503 printf("trapframe: %p, spsr=%08x\n", tf, tf->tf_spsr);
506 printf("r0 =%08x, r1 =%08x, r2 =%08x, r3 =%08x\n",
507 tf->tf_r0, tf->tf_r1, tf->tf_r2, tf->tf_r3);
508 printf("r4 =%08x, r5 =%08x, r6 =%08x, r7 =%08x\n",
509 tf->tf_r4, tf->tf_r5, tf->tf_r6, tf->tf_r7);
510 printf("r8 =%08x, r9 =%08x, r10=%08x, r11=%08x\n",
511 tf->tf_r8, tf->tf_r9, tf->tf_r10, tf->tf_r11);
512 printf("r12=%08x, ", tf->tf_r12);
514 if (TRAP_USERMODE(tf))
515 printf("usp=%08x, ulr=%08x",
516 tf->tf_usr_sp, tf->tf_usr_lr);
518 printf("ssp=%08x, slr=%08x",
519 tf->tf_svc_sp, tf->tf_svc_lr);
520 printf(", pc =%08x\n\n", tf->tf_pc);
523 if (debugger_on_panic || kdb_active)
524 kdb_trap(fsr, 0, tf);
526 panic("Fatal abort");
531 * dab_align() handles the following data aborts:
533 * FAULT_ALIGN_0 - Alignment fault
534 * FAULT_ALIGN_1 - Alignment fault
536 * These faults are fatal if they happen in kernel mode. Otherwise, we
537 * deliver a bus error to the process.
540 dab_align(trapframe_t *tf, u_int fsr, u_int far, struct thread *td, struct ksig *ksig)
543 /* Alignment faults are always fatal if they occur in kernel mode */
544 if (!TRAP_USERMODE(tf)) {
545 if (!td || !td->td_pcb->pcb_onfault)
546 dab_fatal(tf, fsr, far, td, ksig);
548 tf->tf_pc = (int)td->td_pcb->pcb_onfault;
552 /* pcb_onfault *must* be NULL at this point */
554 /* See if the cpu state needs to be fixed up */
555 (void) data_abort_fixup(tf, fsr, far, td, ksig);
557 /* Deliver a bus error signal to the process */
559 ksig->signb = SIGBUS;
566 * dab_buserr() handles the following data aborts:
568 * FAULT_BUSERR_0 - External Abort on Linefetch -- Section
569 * FAULT_BUSERR_1 - External Abort on Linefetch -- Page
570 * FAULT_BUSERR_2 - External Abort on Non-linefetch -- Section
571 * FAULT_BUSERR_3 - External Abort on Non-linefetch -- Page
572 * FAULT_BUSTRNL1 - External abort on Translation -- Level 1
573 * FAULT_BUSTRNL2 - External abort on Translation -- Level 2
575 * If pcb_onfault is set, flag the fault and return to the handler.
576 * If the fault occurred in user mode, give the process a SIGBUS.
578 * Note: On XScale, FAULT_BUSERR_0, FAULT_BUSERR_1, and FAULT_BUSERR_2
579 * can be flagged as imprecise in the FSR. This causes a real headache
580 * since some of the machine state is lost. In this case, tf->tf_pc
581 * may not actually point to the offending instruction. In fact, if
582 * we've taken a double abort fault, it generally points somewhere near
583 * the top of "data_abort_entry" in exception.S.
585 * In all other cases, these data aborts are considered fatal.
588 dab_buserr(trapframe_t *tf, u_int fsr, u_int far, struct thread *td, struct ksig *ksig)
590 struct pcb *pcb = td->td_pcb;
593 if ((fsr & FAULT_IMPRECISE) != 0 &&
594 (tf->tf_spsr & PSR_MODE) == PSR_ABT32_MODE) {
596 * Oops, an imprecise, double abort fault. We've lost the
597 * r14_abt/spsr_abt values corresponding to the original
598 * abort, and the spsr saved in the trapframe indicates
601 tf->tf_spsr &= ~PSR_MODE;
604 * We use a simple heuristic to determine if the double abort
605 * happened as a result of a kernel or user mode access.
606 * If the current trapframe is at the top of the kernel stack,
607 * the fault _must_ have come from user mode.
609 if (tf != ((trapframe_t *)pcb->un_32.pcb32_sp) - 1) {
611 * Kernel mode. We're either about to die a
612 * spectacular death, or pcb_onfault will come
613 * to our rescue. Either way, the current value
614 * of tf->tf_pc is irrelevant.
616 tf->tf_spsr |= PSR_SVC32_MODE;
617 if (pcb->pcb_onfault == NULL)
618 printf("\nKernel mode double abort!\n");
621 * User mode. We've lost the program counter at the
622 * time of the fault (not that it was accurate anyway;
623 * it's not called an imprecise fault for nothing).
624 * About all we can do is copy r14_usr to tf_pc and
625 * hope for the best. The process is about to get a
626 * SIGBUS, so it's probably history anyway.
628 tf->tf_spsr |= PSR_USR32_MODE;
629 tf->tf_pc = tf->tf_usr_lr;
633 /* FAR is invalid for imprecise exceptions */
634 if ((fsr & FAULT_IMPRECISE) != 0)
636 #endif /* __XSCALE__ */
638 if (pcb->pcb_onfault) {
640 tf->tf_pc = (register_t)(intptr_t) pcb->pcb_onfault;
644 /* See if the cpu state needs to be fixed up */
645 (void) data_abort_fixup(tf, fsr, far, td, ksig);
648 * At this point, if the fault happened in kernel mode, we're toast
650 if (!TRAP_USERMODE(tf))
651 dab_fatal(tf, fsr, far, td, ksig);
653 /* Deliver a bus error signal to the process */
654 ksig->signb = SIGBUS;
662 prefetch_abort_fixup(trapframe_t *tf, struct ksig *ksig)
664 #ifdef CPU_ABORT_FIXUP_REQUIRED
667 /* Call the cpu specific prefetch abort fixup routine */
668 error = cpu_prefetchabt_fixup(tf);
669 if (__predict_true(error != ABORT_FIXUP_FAILED))
673 * Oops, couldn't fix up the instruction
676 "prefetch_abort_fixup: fixup for %s mode prefetch abort failed.\n",
677 TRAP_USERMODE(tf) ? "user" : "kernel");
678 printf("pc = 0x%08x, opcode 0x%08x, insn = ", tf->tf_pc,
679 *((u_int *)tf->tf_pc));
680 disassemble(tf->tf_pc);
682 /* Die now if this happened in kernel mode */
683 if (!TRAP_USERMODE(tf))
684 dab_fatal(tf, 0, tf->tf_pc, NULL, ksig);
688 return (ABORT_FIXUP_OK);
689 #endif /* CPU_ABORT_FIXUP_REQUIRED */
693 * void prefetch_abort_handler(trapframe_t *tf)
695 * Abort handler called when instruction execution occurs at
696 * a non existent or restricted (access permissions) memory page.
697 * If the address is invalid and we were in SVC mode then panic as
698 * the kernel should never prefetch abort.
699 * If the address is invalid and the page is mapped then the user process
700 * does no have read permission so send it a signal.
701 * Otherwise fault the page in and try again.
704 prefetch_abort_handler(trapframe_t *tf)
709 vm_offset_t fault_pc, va;
715 /* Update vmmeter statistics */
719 printf("prefetch abort handler: %p %p\n", (void*)tf->tf_pc,
720 (void*)tf->tf_usr_lr);
725 PCPU_INC(cnt.v_trap);
727 if (TRAP_USERMODE(tf)) {
729 if (td->td_ucred != td->td_proc->p_ucred)
730 cred_update_thread(td);
732 fault_pc = tf->tf_pc;
733 if (td->td_md.md_spinlock_count == 0) {
734 if (__predict_true(tf->tf_spsr & I32_bit) == 0)
735 enable_interrupts(I32_bit);
736 if (__predict_true(tf->tf_spsr & F32_bit) == 0)
737 enable_interrupts(F32_bit);
742 /* See if the cpu state needs to be fixed up */
743 switch (prefetch_abort_fixup(tf, &ksig)) {
744 case ABORT_FIXUP_RETURN:
746 case ABORT_FIXUP_FAILED:
747 /* Deliver a SIGILL to the process */
756 /* Prefetch aborts cannot happen in kernel mode */
757 if (__predict_false(!TRAP_USERMODE(tf)))
758 dab_fatal(tf, 0, tf->tf_pc, NULL, &ksig);
762 /* Ok validate the address, can only execute in USER space */
763 if (__predict_false(fault_pc >= VM_MAXUSER_ADDRESS ||
764 (fault_pc < VM_MIN_ADDRESS && vector_page == ARM_VECTORS_LOW))) {
765 ksig.signb = SIGSEGV;
770 map = &td->td_proc->p_vmspace->vm_map;
771 va = trunc_page(fault_pc);
774 * See if the pmap can handle this fault on its own...
777 last_fault_code = -1;
779 if (pmap_fault_fixup(map->pmap, va, VM_PROT_READ, 1))
782 if (map != kernel_map) {
788 error = vm_fault(map, va, VM_PROT_READ | VM_PROT_EXECUTE,
790 if (map != kernel_map) {
796 if (__predict_true(error == 0))
799 if (error == ENOMEM) {
800 printf("VM: pid %d (%s), uid %d killed: "
801 "out of swap\n", td->td_proc->p_pid, td->td_name,
802 (td->td_proc->p_ucred) ?
803 td->td_proc->p_ucred->cr_uid : -1);
804 ksig.signb = SIGKILL;
806 ksig.signb = SIGSEGV;
811 call_trapsignal(td, ksig.signb, ksig.code);
818 extern int badaddr_read_1(const uint8_t *, uint8_t *);
819 extern int badaddr_read_2(const uint16_t *, uint16_t *);
820 extern int badaddr_read_4(const uint32_t *, uint32_t *);
822 * Tentatively read an 8, 16, or 32-bit value from 'addr'.
823 * If the read succeeds, the value is written to 'rptr' and zero is returned.
824 * Else, return EFAULT.
827 badaddr_read(void *addr, size_t size, void *rptr)
836 cpu_drain_writebuf();
838 /* Read from the test address. */
840 case sizeof(uint8_t):
841 rv = badaddr_read_1(addr, &u.v1);
843 *(uint8_t *) rptr = u.v1;
846 case sizeof(uint16_t):
847 rv = badaddr_read_2(addr, &u.v2);
849 *(uint16_t *) rptr = u.v2;
852 case sizeof(uint32_t):
853 rv = badaddr_read_4(addr, &u.v4);
855 *(uint32_t *) rptr = u.v4;
859 panic("badaddr: invalid size (%lu)", (u_long) size);
862 /* Return EFAULT if the address was invalid, else zero */
868 syscall(struct thread *td, trapframe_t *frame, u_int32_t insn)
870 struct proc *p = td->td_proc;
873 register_t *ap, *args, copyargs[MAXARGS];
874 struct sysent *callp;
876 PCPU_INC(cnt.v_syscall);
878 if (td->td_ucred != td->td_proc->p_ucred)
879 cred_update_thread(td);
880 switch (insn & SWI_OS_MASK) {
881 case 0: /* XXX: we need our own one. */
885 call_trapsignal(td, SIGILL, 0);
889 code = insn & 0x000fffff;
892 if (code == SYS_syscall) {
896 } else if (code == SYS___syscall) {
897 code = ap[_QUAD_LOWWORD];
901 if (p->p_sysent->sv_mask)
902 code &= p->p_sysent->sv_mask;
903 if (code >= p->p_sysent->sv_size)
904 callp = &p->p_sysent->sv_table[0];
906 callp = &p->p_sysent->sv_table[code];
907 nargs = callp->sy_narg;
908 memcpy(copyargs, ap, nap * sizeof(register_t));
910 error = copyin((void *)frame->tf_usr_sp, copyargs + nap,
911 (nargs - nap) * sizeof(register_t));
918 if (KTRPOINT(td, KTR_SYSCALL))
919 ktrsyscall(code, nargs, args);
922 CTR4(KTR_SYSC, "syscall enter thread %p pid %d proc %s code %d", td,
923 td->td_proc->p_pid, td->td_name, code);
925 td->td_retval[0] = 0;
926 td->td_retval[1] = 0;
927 STOPEVENT(p, S_SCE, callp->sy_narg);
928 PTRACESTOP_SC(p, td, S_PT_SCE);
929 AUDIT_SYSCALL_ENTER(code, td);
930 error = (*callp->sy_call)(td, args);
931 AUDIT_SYSCALL_EXIT(error, td);
932 KASSERT(td->td_ar == NULL,
933 ("returning from syscall with td_ar set!"));
936 cpu_set_syscall_retval(td, error);
938 WITNESS_WARN(WARN_PANIC, NULL, "System call %s returning",
939 (code >= 0 && code < SYS_MAXSYSCALL) ? syscallnames[code] : "???");
940 KASSERT(td->td_critnest == 0,
941 ("System call %s returning in a critical section",
942 (code >= 0 && code < SYS_MAXSYSCALL) ? syscallnames[code] : "???"));
943 KASSERT(td->td_locks == 0,
944 ("System call %s returning with %d locks held",
945 (code >= 0 && code < SYS_MAXSYSCALL) ? syscallnames[code] : "???",
949 CTR4(KTR_SYSC, "syscall exit thread %p pid %d proc %s code %d", td,
950 td->td_proc->p_pid, td->td_name, code);
952 STOPEVENT(p, S_SCX, code);
953 PTRACESTOP_SC(p, td, S_PT_SCX);
955 if (KTRPOINT(td, KTR_SYSRET))
956 ktrsysret(code, error, td->td_retval[0]);
961 swi_handler(trapframe_t *frame)
963 struct thread *td = curthread;
966 td->td_frame = frame;
970 * Make sure the program counter is correctly aligned so we
971 * don't take an alignment fault trying to read the opcode.
973 if (__predict_false(((frame->tf_pc - INSN_SIZE) & 3) != 0)) {
974 call_trapsignal(td, SIGILL, 0);
978 insn = *(u_int32_t *)(frame->tf_pc - INSN_SIZE);
980 * Enable interrupts if they were enabled before the exception.
981 * Since all syscalls *should* come from user mode it will always
982 * be safe to enable them, but check anyway.
984 if (td->td_md.md_spinlock_count == 0) {
985 if (__predict_true(frame->tf_spsr & I32_bit) == 0)
986 enable_interrupts(I32_bit);
987 if (__predict_true(frame->tf_spsr & F32_bit) == 0)
988 enable_interrupts(F32_bit);
991 syscall(td, frame, insn);