undefined.c revision 157616
153451Speter/* $NetBSD: undefined.c,v 1.22 2003/11/29 22:21:29 bjh21 Exp $ */ 253475Sobrien 353451Speter/*- 453451Speter * Copyright (c) 2001 Ben Harris. 553451Speter * Copyright (c) 1995 Mark Brinicombe. 653475Sobrien * Copyright (c) 1995 Brini. 753451Speter * All rights reserved. 853451Speter * 953451Speter * This code is derived from software written for Brini by Mark Brinicombe 1053451Speter * 1153451Speter * Redistribution and use in source and binary forms, with or without 1253451Speter * modification, are permitted provided that the following conditions 1353451Speter * are met: 1453451Speter * 1. Redistributions of source code must retain the above copyright 1553451Speter * notice, this list of conditions and the following disclaimer. 1653475Sobrien * 2. Redistributions in binary form must reproduce the above copyright 1753475Sobrien * notice, this list of conditions and the following disclaimer in the 1853451Speter * documentation and/or other materials provided with the distribution. 1953475Sobrien * 3. All advertising materials mentioning features or use of this software 2053451Speter * must display the following acknowledgement: 2153451Speter * This product includes software developed by Brini. 2253451Speter * 4. The name of the company nor the name of the author may be used to 2353475Sobrien * endorse or promote products derived from this software without specific 2453475Sobrien * prior written permission. 2553451Speter * 2653451Speter * THIS SOFTWARE IS PROVIDED BY BRINI ``AS IS'' AND ANY EXPRESS OR IMPLIED 2753451Speter * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 28131557Stjr * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 2953451Speter * IN NO EVENT SHALL BRINI OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, 3053451Speter * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES 3153451Speter * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR 3253475Sobrien * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 3353451Speter * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 3453451Speter * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 3553451Speter * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 3653451Speter * SUCH DAMAGE. 3753451Speter * 38131557Stjr * RiscBSD kernel project 3953451Speter * 4053451Speter * undefined.c 4153451Speter * 4253451Speter * Fault handler 43131557Stjr * 4453451Speter * Created : 06/01/95 4553451Speter */ 4653451Speter 4753475Sobrien 4853451Speter#include "opt_ddb.h" 4953451Speter 5053451Speter#include <sys/cdefs.h> 5153451Speter__FBSDID("$FreeBSD: head/sys/arm/arm/undefined.c 157616 2006-04-09 20:16:47Z cognet $"); 5253451Speter 5353451Speter#include <sys/param.h> 5453451Speter#include <sys/malloc.h> 55131557Stjr#include <sys/queue.h> 5653451Speter#include <sys/signal.h> 5753451Speter#include <sys/systm.h> 5853475Sobrien#include <sys/proc.h> 5953451Speter#include <sys/syslog.h> 60#include <sys/vmmeter.h> 61#include <sys/types.h> 62#include <sys/lock.h> 63#include <sys/mutex.h> 64#include <sys/signalvar.h> 65#include <sys/ptrace.h> 66#ifdef KDB 67#include <sys/kdb.h> 68#endif 69#ifdef FAST_FPE 70#include <sys/acct.h> 71#endif 72 73#include <vm/vm.h> 74#include <vm/vm_extern.h> 75 76#include <machine/asm.h> 77#include <machine/cpu.h> 78#include <machine/frame.h> 79#include <machine/undefined.h> 80#include <machine/trap.h> 81 82#include <machine/disassem.h> 83 84#ifdef DDB 85#include <ddb/db_output.h> 86#include <machine/db_machdep.h> 87#endif 88 89#ifdef acorn26 90#include <machine/machdep.h> 91#endif 92 93static int gdb_trapper(u_int, u_int, struct trapframe *, int); 94#ifdef FAST_FPE 95extern int want_resched; 96#endif 97 98LIST_HEAD(, undefined_handler) undefined_handlers[MAX_COPROCS]; 99 100 101void * 102install_coproc_handler(int coproc, undef_handler_t handler) 103{ 104 struct undefined_handler *uh; 105 106 KASSERT(coproc >= 0 && coproc < MAX_COPROCS, ("bad coproc")); 107 KASSERT(handler != NULL, ("handler is NULL")); /* Used to be legal. */ 108 109 /* XXX: M_TEMP??? */ 110 MALLOC(uh, struct undefined_handler *, sizeof(*uh), M_TEMP, M_WAITOK); 111 uh->uh_handler = handler; 112 install_coproc_handler_static(coproc, uh); 113 return uh; 114} 115 116void 117install_coproc_handler_static(int coproc, struct undefined_handler *uh) 118{ 119 120 LIST_INSERT_HEAD(&undefined_handlers[coproc], uh, uh_link); 121} 122 123void 124remove_coproc_handler(void *cookie) 125{ 126 struct undefined_handler *uh = cookie; 127 128 LIST_REMOVE(uh, uh_link); 129 FREE(uh, M_TEMP); 130} 131 132 133static int 134gdb_trapper(u_int addr, u_int insn, struct trapframe *frame, int code) 135{ 136 struct thread *td; 137 ksiginfo_t ksi; 138 139 td = (curthread == NULL) ? &thread0 : curthread; 140 141 if (insn == GDB_BREAKPOINT || insn == GDB5_BREAKPOINT) { 142 if (code == FAULT_USER) { 143 ksiginfo_init_trap(&ksi); 144 ksi.ksi_signo = SIGTRAP; 145 ksi.ksi_code = TRAP_BRKPT; 146 ksi.ksi_addr = (u_int32_t *)addr; 147 trapsignal(td, &ksi); 148 return 0; 149 } 150#if 0 151#ifdef KGDB 152 return !kgdb_trap(T_BREAKPOINT, frame); 153#endif 154#endif 155 } 156 return 1; 157} 158 159static struct undefined_handler gdb_uh; 160 161void 162undefined_init() 163{ 164 int loop; 165 166 /* Not actually necessary -- the initialiser is just NULL */ 167 for (loop = 0; loop < MAX_COPROCS; ++loop) 168 LIST_INIT(&undefined_handlers[loop]); 169 170 /* Install handler for GDB breakpoints */ 171 gdb_uh.uh_handler = gdb_trapper; 172 install_coproc_handler_static(0, &gdb_uh); 173} 174 175 176void 177undefinedinstruction(trapframe_t *frame) 178{ 179 struct thread *td; 180 u_int fault_pc; 181 int fault_instruction; 182 int fault_code; 183 int coprocessor; 184 struct undefined_handler *uh; 185#ifdef VERBOSE_ARM32 186 int s; 187#endif 188 ksiginfo_t ksi; 189 190 /* Enable interrupts if they were enabled before the exception. */ 191 if (!(frame->tf_spsr & I32_bit)) 192 enable_interrupts(I32_bit|F32_bit); 193 194 frame->tf_pc -= INSN_SIZE; 195 PCPU_LAZY_INC(cnt.v_trap); 196 197 fault_pc = frame->tf_pc; 198 199 /* 200 * Get the current thread/proc structure or thread0/proc0 if there is 201 * none. 202 */ 203 td = curthread == NULL ? &thread0 : curthread; 204 205 /* 206 * Make sure the program counter is correctly aligned so we 207 * don't take an alignment fault trying to read the opcode. 208 */ 209 if (__predict_false((fault_pc & 3) != 0)) { 210 ksiginfo_init_trap(&ksi); 211 ksi.ksi_signo = SIGILL; 212 ksi.ksi_code = ILL_ILLADR; 213 ksi.ksi_addr = (u_int32_t *)(intptr_t) fault_pc; 214 trapsignal(td, &ksi); 215 userret(td, frame); 216 return; 217 } 218 219 /* 220 * Should use fuword() here .. but in the interests of squeezing every 221 * bit of speed we will just use ReadWord(). We know the instruction 222 * can be read as was just executed so this will never fail unless the 223 * kernel is screwed up in which case it does not really matter does 224 * it ? 225 */ 226 227 fault_instruction = *(u_int32_t *)fault_pc; 228 229 /* Update vmmeter statistics */ 230#if 0 231 uvmexp.traps++; 232#endif 233 /* Check for coprocessor instruction */ 234 235 /* 236 * According to the datasheets you only need to look at bit 27 of the 237 * instruction to tell the difference between and undefined 238 * instruction and a coprocessor instruction following an undefined 239 * instruction trap. 240 */ 241 242 if ((fault_instruction & (1 << 27)) != 0) 243 coprocessor = (fault_instruction >> 8) & 0x0f; 244 else 245 coprocessor = 0; 246 247 if ((frame->tf_spsr & PSR_MODE) == PSR_USR32_MODE) { 248 /* 249 * Modify the fault_code to reflect the USR/SVC state at 250 * time of fault. 251 */ 252 fault_code = FAULT_USER; 253 td->td_frame = frame; 254 } else 255 fault_code = 0; 256 257 /* OK this is were we do something about the instruction. */ 258 LIST_FOREACH(uh, &undefined_handlers[coprocessor], uh_link) 259 if (uh->uh_handler(fault_pc, fault_instruction, frame, 260 fault_code) == 0) 261 break; 262 263 if (fault_code & FAULT_USER && fault_instruction == PTRACE_BREAKPOINT) { 264 PROC_LOCK(td->td_proc); 265 _PHOLD(td->td_proc); 266 ptrace_clear_single_step(td); 267 _PRELE(td->td_proc); 268 PROC_UNLOCK(td->td_proc); 269 return; 270 } 271 272 if (uh == NULL && (fault_code & FAULT_USER)) { 273 /* Fault has not been handled */ 274 ksiginfo_init_trap(&ksi); 275 ksi.ksi_signo = SIGILL; 276 ksi.ksi_code = ILL_ILLOPC; 277 ksi.ksi_addr = (u_int32_t *)(intptr_t) fault_pc; 278 trapsignal(td, &ksi); 279 } 280 281 if ((fault_code & FAULT_USER) == 0) { 282 if (fault_instruction == KERNEL_BREAKPOINT) { 283#ifdef KDB 284 kdb_trap(T_BREAKPOINT, 0, frame); 285#else 286 printf("No debugger in kernel.\n"); 287#endif 288 return; 289 } else 290 panic("Undefined instruction in kernel.\n"); 291 } 292 293#ifdef FAST_FPE 294 /* Optimised exit code */ 295 { 296 297 /* 298 * Check for reschedule request, at the moment there is only 299 * 1 ast so this code should always be run 300 */ 301 302 if (want_resched) { 303 /* 304 * We are being preempted. 305 */ 306 preempt(0); 307 } 308 309 /* Invoke MI userret code */ 310 mi_userret(td); 311 312#if 0 313 l->l_priority = l->l_usrpri; 314 315 curcpu()->ci_schedstate.spc_curpriority = l->l_priority; 316#endif 317 } 318 319#else 320 userret(td, frame); 321#endif 322} 323