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v5.9
   1/*
   2 *  linux/arch/m68k/kernel/traps.c
   3 *
   4 *  Copyright (C) 1993, 1994 by Hamish Macdonald
   5 *
   6 *  68040 fixes by Michael Rausch
   7 *  68040 fixes by Martin Apel
   8 *  68040 fixes and writeback by Richard Zidlicky
   9 *  68060 fixes by Roman Hodek
  10 *  68060 fixes by Jesper Skov
  11 *
  12 * This file is subject to the terms and conditions of the GNU General Public
  13 * License.  See the file COPYING in the main directory of this archive
  14 * for more details.
  15 */
  16
  17/*
  18 * Sets up all exception vectors
  19 */
  20
  21#include <linux/sched.h>
  22#include <linux/sched/debug.h>
  23#include <linux/signal.h>
  24#include <linux/kernel.h>
  25#include <linux/mm.h>
  26#include <linux/module.h>
  27#include <linux/user.h>
  28#include <linux/string.h>
  29#include <linux/linkage.h>
  30#include <linux/init.h>
  31#include <linux/ptrace.h>
  32#include <linux/kallsyms.h>
  33
  34#include <asm/setup.h>
  35#include <asm/fpu.h>
  36#include <linux/uaccess.h>
  37#include <asm/traps.h>
 
  38#include <asm/machdep.h>
  39#include <asm/siginfo.h>
  40#include <asm/tlbflush.h>
  41
  42static const char *vec_names[] = {
  43	[VEC_RESETSP]	= "RESET SP",
  44	[VEC_RESETPC]	= "RESET PC",
  45	[VEC_BUSERR]	= "BUS ERROR",
  46	[VEC_ADDRERR]	= "ADDRESS ERROR",
  47	[VEC_ILLEGAL]	= "ILLEGAL INSTRUCTION",
  48	[VEC_ZERODIV]	= "ZERO DIVIDE",
  49	[VEC_CHK]	= "CHK",
  50	[VEC_TRAP]	= "TRAPcc",
  51	[VEC_PRIV]	= "PRIVILEGE VIOLATION",
  52	[VEC_TRACE]	= "TRACE",
  53	[VEC_LINE10]	= "LINE 1010",
  54	[VEC_LINE11]	= "LINE 1111",
  55	[VEC_RESV12]	= "UNASSIGNED RESERVED 12",
  56	[VEC_COPROC]	= "COPROCESSOR PROTOCOL VIOLATION",
  57	[VEC_FORMAT]	= "FORMAT ERROR",
  58	[VEC_UNINT]	= "UNINITIALIZED INTERRUPT",
  59	[VEC_RESV16]	= "UNASSIGNED RESERVED 16",
  60	[VEC_RESV17]	= "UNASSIGNED RESERVED 17",
  61	[VEC_RESV18]	= "UNASSIGNED RESERVED 18",
  62	[VEC_RESV19]	= "UNASSIGNED RESERVED 19",
  63	[VEC_RESV20]	= "UNASSIGNED RESERVED 20",
  64	[VEC_RESV21]	= "UNASSIGNED RESERVED 21",
  65	[VEC_RESV22]	= "UNASSIGNED RESERVED 22",
  66	[VEC_RESV23]	= "UNASSIGNED RESERVED 23",
  67	[VEC_SPUR]	= "SPURIOUS INTERRUPT",
  68	[VEC_INT1]	= "LEVEL 1 INT",
  69	[VEC_INT2]	= "LEVEL 2 INT",
  70	[VEC_INT3]	= "LEVEL 3 INT",
  71	[VEC_INT4]	= "LEVEL 4 INT",
  72	[VEC_INT5]	= "LEVEL 5 INT",
  73	[VEC_INT6]	= "LEVEL 6 INT",
  74	[VEC_INT7]	= "LEVEL 7 INT",
  75	[VEC_SYS]	= "SYSCALL",
  76	[VEC_TRAP1]	= "TRAP #1",
  77	[VEC_TRAP2]	= "TRAP #2",
  78	[VEC_TRAP3]	= "TRAP #3",
  79	[VEC_TRAP4]	= "TRAP #4",
  80	[VEC_TRAP5]	= "TRAP #5",
  81	[VEC_TRAP6]	= "TRAP #6",
  82	[VEC_TRAP7]	= "TRAP #7",
  83	[VEC_TRAP8]	= "TRAP #8",
  84	[VEC_TRAP9]	= "TRAP #9",
  85	[VEC_TRAP10]	= "TRAP #10",
  86	[VEC_TRAP11]	= "TRAP #11",
  87	[VEC_TRAP12]	= "TRAP #12",
  88	[VEC_TRAP13]	= "TRAP #13",
  89	[VEC_TRAP14]	= "TRAP #14",
  90	[VEC_TRAP15]	= "TRAP #15",
  91	[VEC_FPBRUC]	= "FPCP BSUN",
  92	[VEC_FPIR]	= "FPCP INEXACT",
  93	[VEC_FPDIVZ]	= "FPCP DIV BY 0",
  94	[VEC_FPUNDER]	= "FPCP UNDERFLOW",
  95	[VEC_FPOE]	= "FPCP OPERAND ERROR",
  96	[VEC_FPOVER]	= "FPCP OVERFLOW",
  97	[VEC_FPNAN]	= "FPCP SNAN",
  98	[VEC_FPUNSUP]	= "FPCP UNSUPPORTED OPERATION",
  99	[VEC_MMUCFG]	= "MMU CONFIGURATION ERROR",
 100	[VEC_MMUILL]	= "MMU ILLEGAL OPERATION ERROR",
 101	[VEC_MMUACC]	= "MMU ACCESS LEVEL VIOLATION ERROR",
 102	[VEC_RESV59]	= "UNASSIGNED RESERVED 59",
 103	[VEC_UNIMPEA]	= "UNASSIGNED RESERVED 60",
 104	[VEC_UNIMPII]	= "UNASSIGNED RESERVED 61",
 105	[VEC_RESV62]	= "UNASSIGNED RESERVED 62",
 106	[VEC_RESV63]	= "UNASSIGNED RESERVED 63",
 107};
 108
 109static const char *space_names[] = {
 110	[0]		= "Space 0",
 111	[USER_DATA]	= "User Data",
 112	[USER_PROGRAM]	= "User Program",
 113#ifndef CONFIG_SUN3
 114	[3]		= "Space 3",
 115#else
 116	[FC_CONTROL]	= "Control",
 117#endif
 118	[4]		= "Space 4",
 119	[SUPER_DATA]	= "Super Data",
 120	[SUPER_PROGRAM]	= "Super Program",
 121	[CPU_SPACE]	= "CPU"
 122};
 123
 124void die_if_kernel(char *,struct pt_regs *,int);
 125asmlinkage int do_page_fault(struct pt_regs *regs, unsigned long address,
 126                             unsigned long error_code);
 127int send_fault_sig(struct pt_regs *regs);
 128
 129asmlinkage void trap_c(struct frame *fp);
 130
 131#if defined (CONFIG_M68060)
 132static inline void access_error060 (struct frame *fp)
 133{
 134	unsigned long fslw = fp->un.fmt4.pc; /* is really FSLW for access error */
 135
 136	pr_debug("fslw=%#lx, fa=%#lx\n", fslw, fp->un.fmt4.effaddr);
 137
 138	if (fslw & MMU060_BPE) {
 139		/* branch prediction error -> clear branch cache */
 140		__asm__ __volatile__ ("movec %/cacr,%/d0\n\t"
 141				      "orl   #0x00400000,%/d0\n\t"
 142				      "movec %/d0,%/cacr"
 143				      : : : "d0" );
 144		/* return if there's no other error */
 145		if (!(fslw & MMU060_ERR_BITS) && !(fslw & MMU060_SEE))
 146			return;
 147	}
 148
 149	if (fslw & (MMU060_DESC_ERR | MMU060_WP | MMU060_SP)) {
 150		unsigned long errorcode;
 151		unsigned long addr = fp->un.fmt4.effaddr;
 152
 153		if (fslw & MMU060_MA)
 154			addr = (addr + PAGE_SIZE - 1) & PAGE_MASK;
 155
 156		errorcode = 1;
 157		if (fslw & MMU060_DESC_ERR) {
 158			__flush_tlb040_one(addr);
 159			errorcode = 0;
 160		}
 161		if (fslw & MMU060_W)
 162			errorcode |= 2;
 163		pr_debug("errorcode = %ld\n", errorcode);
 164		do_page_fault(&fp->ptregs, addr, errorcode);
 165	} else if (fslw & (MMU060_SEE)){
 166		/* Software Emulation Error.
 167		 * fault during mem_read/mem_write in ifpsp060/os.S
 168		 */
 169		send_fault_sig(&fp->ptregs);
 170	} else if (!(fslw & (MMU060_RE|MMU060_WE)) ||
 171		   send_fault_sig(&fp->ptregs) > 0) {
 172		pr_err("pc=%#lx, fa=%#lx\n", fp->ptregs.pc,
 173		       fp->un.fmt4.effaddr);
 174		pr_err("68060 access error, fslw=%lx\n", fslw);
 175		trap_c( fp );
 176	}
 177}
 178#endif /* CONFIG_M68060 */
 179
 180#if defined (CONFIG_M68040)
 181static inline unsigned long probe040(int iswrite, unsigned long addr, int wbs)
 182{
 183	unsigned long mmusr;
 184	mm_segment_t old_fs = get_fs();
 185
 186	set_fs(MAKE_MM_SEG(wbs));
 187
 188	if (iswrite)
 189		asm volatile (".chip 68040; ptestw (%0); .chip 68k" : : "a" (addr));
 190	else
 191		asm volatile (".chip 68040; ptestr (%0); .chip 68k" : : "a" (addr));
 192
 193	asm volatile (".chip 68040; movec %%mmusr,%0; .chip 68k" : "=r" (mmusr));
 194
 195	set_fs(old_fs);
 196
 197	return mmusr;
 198}
 199
 200static inline int do_040writeback1(unsigned short wbs, unsigned long wba,
 201				   unsigned long wbd)
 202{
 203	int res = 0;
 204	mm_segment_t old_fs = get_fs();
 205
 206	/* set_fs can not be moved, otherwise put_user() may oops */
 207	set_fs(MAKE_MM_SEG(wbs));
 208
 209	switch (wbs & WBSIZ_040) {
 210	case BA_SIZE_BYTE:
 211		res = put_user(wbd & 0xff, (char __user *)wba);
 212		break;
 213	case BA_SIZE_WORD:
 214		res = put_user(wbd & 0xffff, (short __user *)wba);
 215		break;
 216	case BA_SIZE_LONG:
 217		res = put_user(wbd, (int __user *)wba);
 218		break;
 219	}
 220
 221	/* set_fs can not be moved, otherwise put_user() may oops */
 222	set_fs(old_fs);
 223
 224
 225	pr_debug("do_040writeback1, res=%d\n", res);
 226
 227	return res;
 228}
 229
 230/* after an exception in a writeback the stack frame corresponding
 231 * to that exception is discarded, set a few bits in the old frame
 232 * to simulate what it should look like
 233 */
 234static inline void fix_xframe040(struct frame *fp, unsigned long wba, unsigned short wbs)
 235{
 236	fp->un.fmt7.faddr = wba;
 237	fp->un.fmt7.ssw = wbs & 0xff;
 238	if (wba != current->thread.faddr)
 239	    fp->un.fmt7.ssw |= MA_040;
 240}
 241
 242static inline void do_040writebacks(struct frame *fp)
 243{
 244	int res = 0;
 245#if 0
 246	if (fp->un.fmt7.wb1s & WBV_040)
 247		pr_err("access_error040: cannot handle 1st writeback. oops.\n");
 248#endif
 249
 250	if ((fp->un.fmt7.wb2s & WBV_040) &&
 251	    !(fp->un.fmt7.wb2s & WBTT_040)) {
 252		res = do_040writeback1(fp->un.fmt7.wb2s, fp->un.fmt7.wb2a,
 253				       fp->un.fmt7.wb2d);
 254		if (res)
 255			fix_xframe040(fp, fp->un.fmt7.wb2a, fp->un.fmt7.wb2s);
 256		else
 257			fp->un.fmt7.wb2s = 0;
 258	}
 259
 260	/* do the 2nd wb only if the first one was successful (except for a kernel wb) */
 261	if (fp->un.fmt7.wb3s & WBV_040 && (!res || fp->un.fmt7.wb3s & 4)) {
 262		res = do_040writeback1(fp->un.fmt7.wb3s, fp->un.fmt7.wb3a,
 263				       fp->un.fmt7.wb3d);
 264		if (res)
 265		    {
 266			fix_xframe040(fp, fp->un.fmt7.wb3a, fp->un.fmt7.wb3s);
 267
 268			fp->un.fmt7.wb2s = fp->un.fmt7.wb3s;
 269			fp->un.fmt7.wb3s &= (~WBV_040);
 270			fp->un.fmt7.wb2a = fp->un.fmt7.wb3a;
 271			fp->un.fmt7.wb2d = fp->un.fmt7.wb3d;
 272		    }
 273		else
 274			fp->un.fmt7.wb3s = 0;
 275	}
 276
 277	if (res)
 278		send_fault_sig(&fp->ptregs);
 279}
 280
 281/*
 282 * called from sigreturn(), must ensure userspace code didn't
 283 * manipulate exception frame to circumvent protection, then complete
 284 * pending writebacks
 285 * we just clear TM2 to turn it into a userspace access
 286 */
 287asmlinkage void berr_040cleanup(struct frame *fp)
 288{
 289	fp->un.fmt7.wb2s &= ~4;
 290	fp->un.fmt7.wb3s &= ~4;
 291
 292	do_040writebacks(fp);
 293}
 294
 295static inline void access_error040(struct frame *fp)
 296{
 297	unsigned short ssw = fp->un.fmt7.ssw;
 298	unsigned long mmusr;
 299
 300	pr_debug("ssw=%#x, fa=%#lx\n", ssw, fp->un.fmt7.faddr);
 301	pr_debug("wb1s=%#x, wb2s=%#x, wb3s=%#x\n", fp->un.fmt7.wb1s,
 302		fp->un.fmt7.wb2s, fp->un.fmt7.wb3s);
 303	pr_debug("wb2a=%lx, wb3a=%lx, wb2d=%lx, wb3d=%lx\n",
 304		fp->un.fmt7.wb2a, fp->un.fmt7.wb3a,
 305		fp->un.fmt7.wb2d, fp->un.fmt7.wb3d);
 306
 307	if (ssw & ATC_040) {
 308		unsigned long addr = fp->un.fmt7.faddr;
 309		unsigned long errorcode;
 310
 311		/*
 312		 * The MMU status has to be determined AFTER the address
 313		 * has been corrected if there was a misaligned access (MA).
 314		 */
 315		if (ssw & MA_040)
 316			addr = (addr + 7) & -8;
 317
 318		/* MMU error, get the MMUSR info for this access */
 319		mmusr = probe040(!(ssw & RW_040), addr, ssw);
 320		pr_debug("mmusr = %lx\n", mmusr);
 321		errorcode = 1;
 322		if (!(mmusr & MMU_R_040)) {
 323			/* clear the invalid atc entry */
 324			__flush_tlb040_one(addr);
 325			errorcode = 0;
 326		}
 327
 328		/* despite what documentation seems to say, RMW
 329		 * accesses have always both the LK and RW bits set */
 330		if (!(ssw & RW_040) || (ssw & LK_040))
 331			errorcode |= 2;
 332
 333		if (do_page_fault(&fp->ptregs, addr, errorcode)) {
 334			pr_debug("do_page_fault() !=0\n");
 335			if (user_mode(&fp->ptregs)){
 336				/* delay writebacks after signal delivery */
 337				pr_debug(".. was usermode - return\n");
 338				return;
 339			}
 340			/* disable writeback into user space from kernel
 341			 * (if do_page_fault didn't fix the mapping,
 342                         * the writeback won't do good)
 343			 */
 344disable_wb:
 345			pr_debug(".. disabling wb2\n");
 346			if (fp->un.fmt7.wb2a == fp->un.fmt7.faddr)
 347				fp->un.fmt7.wb2s &= ~WBV_040;
 348			if (fp->un.fmt7.wb3a == fp->un.fmt7.faddr)
 349				fp->un.fmt7.wb3s &= ~WBV_040;
 350		}
 351	} else {
 352		/* In case of a bus error we either kill the process or expect
 353		 * the kernel to catch the fault, which then is also responsible
 354		 * for cleaning up the mess.
 355		 */
 356		current->thread.signo = SIGBUS;
 357		current->thread.faddr = fp->un.fmt7.faddr;
 358		if (send_fault_sig(&fp->ptregs) >= 0)
 359			pr_err("68040 bus error (ssw=%x, faddr=%lx)\n", ssw,
 360			       fp->un.fmt7.faddr);
 361		goto disable_wb;
 362	}
 363
 364	do_040writebacks(fp);
 365}
 366#endif /* CONFIG_M68040 */
 367
 368#if defined(CONFIG_SUN3)
 369#include <asm/sun3mmu.h>
 370
 371extern int mmu_emu_handle_fault (unsigned long, int, int);
 372
 373/* sun3 version of bus_error030 */
 374
 375static inline void bus_error030 (struct frame *fp)
 376{
 377	unsigned char buserr_type = sun3_get_buserr ();
 378	unsigned long addr, errorcode;
 379	unsigned short ssw = fp->un.fmtb.ssw;
 380	extern unsigned long _sun3_map_test_start, _sun3_map_test_end;
 381
 382	if (ssw & (FC | FB))
 383		pr_debug("Instruction fault at %#010lx\n",
 384			ssw & FC ?
 385			fp->ptregs.format == 0xa ? fp->ptregs.pc + 2 : fp->un.fmtb.baddr - 2
 386			:
 387			fp->ptregs.format == 0xa ? fp->ptregs.pc + 4 : fp->un.fmtb.baddr);
 388	if (ssw & DF)
 389		pr_debug("Data %s fault at %#010lx in %s (pc=%#lx)\n",
 390			ssw & RW ? "read" : "write",
 391			fp->un.fmtb.daddr,
 392			space_names[ssw & DFC], fp->ptregs.pc);
 393
 394	/*
 395	 * Check if this page should be demand-mapped. This needs to go before
 396	 * the testing for a bad kernel-space access (demand-mapping applies
 397	 * to kernel accesses too).
 398	 */
 399
 400	if ((ssw & DF)
 401	    && (buserr_type & (SUN3_BUSERR_PROTERR | SUN3_BUSERR_INVALID))) {
 402		if (mmu_emu_handle_fault (fp->un.fmtb.daddr, ssw & RW, 0))
 403			return;
 404	}
 405
 406	/* Check for kernel-space pagefault (BAD). */
 407	if (fp->ptregs.sr & PS_S) {
 408		/* kernel fault must be a data fault to user space */
 409		if (! ((ssw & DF) && ((ssw & DFC) == USER_DATA))) {
 410		     // try checking the kernel mappings before surrender
 411		     if (mmu_emu_handle_fault (fp->un.fmtb.daddr, ssw & RW, 1))
 412			  return;
 413			/* instruction fault or kernel data fault! */
 414			if (ssw & (FC | FB))
 415				pr_err("Instruction fault at %#010lx\n",
 416					fp->ptregs.pc);
 417			if (ssw & DF) {
 418				/* was this fault incurred testing bus mappings? */
 419				if((fp->ptregs.pc >= (unsigned long)&_sun3_map_test_start) &&
 420				   (fp->ptregs.pc <= (unsigned long)&_sun3_map_test_end)) {
 421					send_fault_sig(&fp->ptregs);
 422					return;
 423				}
 424
 425				pr_err("Data %s fault at %#010lx in %s (pc=%#lx)\n",
 426					ssw & RW ? "read" : "write",
 427					fp->un.fmtb.daddr,
 428					space_names[ssw & DFC], fp->ptregs.pc);
 429			}
 430			pr_err("BAD KERNEL BUSERR\n");
 431
 432			die_if_kernel("Oops", &fp->ptregs,0);
 433			force_sig(SIGKILL);
 434			return;
 435		}
 436	} else {
 437		/* user fault */
 438		if (!(ssw & (FC | FB)) && !(ssw & DF))
 439			/* not an instruction fault or data fault! BAD */
 440			panic ("USER BUSERR w/o instruction or data fault");
 441	}
 442
 443
 444	/* First handle the data fault, if any.  */
 445	if (ssw & DF) {
 446		addr = fp->un.fmtb.daddr;
 447
 448// errorcode bit 0:	0 -> no page		1 -> protection fault
 449// errorcode bit 1:	0 -> read fault		1 -> write fault
 450
 451// (buserr_type & SUN3_BUSERR_PROTERR)	-> protection fault
 452// (buserr_type & SUN3_BUSERR_INVALID)	-> invalid page fault
 453
 454		if (buserr_type & SUN3_BUSERR_PROTERR)
 455			errorcode = 0x01;
 456		else if (buserr_type & SUN3_BUSERR_INVALID)
 457			errorcode = 0x00;
 458		else {
 459			pr_debug("*** unexpected busfault type=%#04x\n",
 460				 buserr_type);
 461			pr_debug("invalid %s access at %#lx from pc %#lx\n",
 462				 !(ssw & RW) ? "write" : "read", addr,
 463				 fp->ptregs.pc);
 464			die_if_kernel ("Oops", &fp->ptregs, buserr_type);
 465			force_sig (SIGBUS);
 466			return;
 467		}
 468
 469//todo: wtf is RM bit? --m
 470		if (!(ssw & RW) || ssw & RM)
 471			errorcode |= 0x02;
 472
 473		/* Handle page fault. */
 474		do_page_fault (&fp->ptregs, addr, errorcode);
 475
 476		/* Retry the data fault now. */
 477		return;
 478	}
 479
 480	/* Now handle the instruction fault. */
 481
 482	/* Get the fault address. */
 483	if (fp->ptregs.format == 0xA)
 484		addr = fp->ptregs.pc + 4;
 485	else
 486		addr = fp->un.fmtb.baddr;
 487	if (ssw & FC)
 488		addr -= 2;
 489
 490	if (buserr_type & SUN3_BUSERR_INVALID) {
 491		if (!mmu_emu_handle_fault(addr, 1, 0))
 492			do_page_fault (&fp->ptregs, addr, 0);
 493       } else {
 494		pr_debug("protection fault on insn access (segv).\n");
 495		force_sig (SIGSEGV);
 496       }
 497}
 498#else
 499#if defined(CPU_M68020_OR_M68030)
 500static inline void bus_error030 (struct frame *fp)
 501{
 502	volatile unsigned short temp;
 503	unsigned short mmusr;
 504	unsigned long addr, errorcode;
 505	unsigned short ssw = fp->un.fmtb.ssw;
 506#ifdef DEBUG
 507	unsigned long desc;
 508#endif
 509
 510	pr_debug("pid = %x  ", current->pid);
 511	pr_debug("SSW=%#06x  ", ssw);
 512
 513	if (ssw & (FC | FB))
 514		pr_debug("Instruction fault at %#010lx\n",
 515			ssw & FC ?
 516			fp->ptregs.format == 0xa ? fp->ptregs.pc + 2 : fp->un.fmtb.baddr - 2
 517			:
 518			fp->ptregs.format == 0xa ? fp->ptregs.pc + 4 : fp->un.fmtb.baddr);
 519	if (ssw & DF)
 520		pr_debug("Data %s fault at %#010lx in %s (pc=%#lx)\n",
 521			ssw & RW ? "read" : "write",
 522			fp->un.fmtb.daddr,
 523			space_names[ssw & DFC], fp->ptregs.pc);
 524
 525	/* ++andreas: If a data fault and an instruction fault happen
 526	   at the same time map in both pages.  */
 527
 528	/* First handle the data fault, if any.  */
 529	if (ssw & DF) {
 530		addr = fp->un.fmtb.daddr;
 531
 532#ifdef DEBUG
 533		asm volatile ("ptestr %3,%2@,#7,%0\n\t"
 534			      "pmove %%psr,%1"
 535			      : "=a&" (desc), "=m" (temp)
 536			      : "a" (addr), "d" (ssw));
 537		pr_debug("mmusr is %#x for addr %#lx in task %p\n",
 538			 temp, addr, current);
 539		pr_debug("descriptor address is 0x%p, contents %#lx\n",
 540			 __va(desc), *(unsigned long *)__va(desc));
 541#else
 542		asm volatile ("ptestr %2,%1@,#7\n\t"
 543			      "pmove %%psr,%0"
 544			      : "=m" (temp) : "a" (addr), "d" (ssw));
 545#endif
 546		mmusr = temp;
 547		errorcode = (mmusr & MMU_I) ? 0 : 1;
 548		if (!(ssw & RW) || (ssw & RM))
 549			errorcode |= 2;
 550
 551		if (mmusr & (MMU_I | MMU_WP)) {
 552			if (ssw & 4) {
 553				pr_err("Data %s fault at %#010lx in %s (pc=%#lx)\n",
 554				       ssw & RW ? "read" : "write",
 555				       fp->un.fmtb.daddr,
 556				       space_names[ssw & DFC], fp->ptregs.pc);
 557				goto buserr;
 558			}
 559			/* Don't try to do anything further if an exception was
 560			   handled. */
 561			if (do_page_fault (&fp->ptregs, addr, errorcode) < 0)
 562				return;
 563		} else if (!(mmusr & MMU_I)) {
 564			/* probably a 020 cas fault */
 565			if (!(ssw & RM) && send_fault_sig(&fp->ptregs) > 0)
 566				pr_err("unexpected bus error (%#x,%#x)\n", ssw,
 567				       mmusr);
 568		} else if (mmusr & (MMU_B|MMU_L|MMU_S)) {
 569			pr_err("invalid %s access at %#lx from pc %#lx\n",
 570			       !(ssw & RW) ? "write" : "read", addr,
 571			       fp->ptregs.pc);
 572			die_if_kernel("Oops",&fp->ptregs,mmusr);
 573			force_sig(SIGSEGV);
 574			return;
 575		} else {
 576#if 0
 577			static volatile long tlong;
 578#endif
 579
 580			pr_err("weird %s access at %#lx from pc %#lx (ssw is %#x)\n",
 581			       !(ssw & RW) ? "write" : "read", addr,
 582			       fp->ptregs.pc, ssw);
 583			asm volatile ("ptestr #1,%1@,#0\n\t"
 584				      "pmove %%psr,%0"
 585				      : "=m" (temp)
 586				      : "a" (addr));
 587			mmusr = temp;
 588
 589			pr_err("level 0 mmusr is %#x\n", mmusr);
 590#if 0
 591			asm volatile ("pmove %%tt0,%0"
 592				      : "=m" (tlong));
 593			pr_debug("tt0 is %#lx, ", tlong);
 594			asm volatile ("pmove %%tt1,%0"
 595				      : "=m" (tlong));
 596			pr_debug("tt1 is %#lx\n", tlong);
 597#endif
 598			pr_debug("Unknown SIGSEGV - 1\n");
 599			die_if_kernel("Oops",&fp->ptregs,mmusr);
 600			force_sig(SIGSEGV);
 601			return;
 602		}
 603
 604		/* setup an ATC entry for the access about to be retried */
 605		if (!(ssw & RW) || (ssw & RM))
 606			asm volatile ("ploadw %1,%0@" : /* no outputs */
 607				      : "a" (addr), "d" (ssw));
 608		else
 609			asm volatile ("ploadr %1,%0@" : /* no outputs */
 610				      : "a" (addr), "d" (ssw));
 611	}
 612
 613	/* Now handle the instruction fault. */
 614
 615	if (!(ssw & (FC|FB)))
 616		return;
 617
 618	if (fp->ptregs.sr & PS_S) {
 619		pr_err("Instruction fault at %#010lx\n", fp->ptregs.pc);
 620	buserr:
 621		pr_err("BAD KERNEL BUSERR\n");
 622		die_if_kernel("Oops",&fp->ptregs,0);
 623		force_sig(SIGKILL);
 624		return;
 625	}
 626
 627	/* get the fault address */
 628	if (fp->ptregs.format == 10)
 629		addr = fp->ptregs.pc + 4;
 630	else
 631		addr = fp->un.fmtb.baddr;
 632	if (ssw & FC)
 633		addr -= 2;
 634
 635	if ((ssw & DF) && ((addr ^ fp->un.fmtb.daddr) & PAGE_MASK) == 0)
 636		/* Insn fault on same page as data fault.  But we
 637		   should still create the ATC entry.  */
 638		goto create_atc_entry;
 639
 640#ifdef DEBUG
 641	asm volatile ("ptestr #1,%2@,#7,%0\n\t"
 642		      "pmove %%psr,%1"
 643		      : "=a&" (desc), "=m" (temp)
 644		      : "a" (addr));
 645	pr_debug("mmusr is %#x for addr %#lx in task %p\n",
 646		temp, addr, current);
 647	pr_debug("descriptor address is 0x%p, contents %#lx\n",
 648		__va(desc), *(unsigned long *)__va(desc));
 649#else
 650	asm volatile ("ptestr #1,%1@,#7\n\t"
 651		      "pmove %%psr,%0"
 652		      : "=m" (temp) : "a" (addr));
 653#endif
 654	mmusr = temp;
 655	if (mmusr & MMU_I)
 656		do_page_fault (&fp->ptregs, addr, 0);
 657	else if (mmusr & (MMU_B|MMU_L|MMU_S)) {
 658		pr_err("invalid insn access at %#lx from pc %#lx\n",
 659			addr, fp->ptregs.pc);
 660		pr_debug("Unknown SIGSEGV - 2\n");
 661		die_if_kernel("Oops",&fp->ptregs,mmusr);
 662		force_sig(SIGSEGV);
 663		return;
 664	}
 665
 666create_atc_entry:
 667	/* setup an ATC entry for the access about to be retried */
 668	asm volatile ("ploadr #2,%0@" : /* no outputs */
 669		      : "a" (addr));
 670}
 671#endif /* CPU_M68020_OR_M68030 */
 672#endif /* !CONFIG_SUN3 */
 673
 674#if defined(CONFIG_COLDFIRE) && defined(CONFIG_MMU)
 675#include <asm/mcfmmu.h>
 676
 677/*
 678 *	The following table converts the FS encoding of a ColdFire
 679 *	exception stack frame into the error_code value needed by
 680 *	do_fault.
 681*/
 682static const unsigned char fs_err_code[] = {
 683	0,  /* 0000 */
 684	0,  /* 0001 */
 685	0,  /* 0010 */
 686	0,  /* 0011 */
 687	1,  /* 0100 */
 688	0,  /* 0101 */
 689	0,  /* 0110 */
 690	0,  /* 0111 */
 691	2,  /* 1000 */
 692	3,  /* 1001 */
 693	2,  /* 1010 */
 694	0,  /* 1011 */
 695	1,  /* 1100 */
 696	1,  /* 1101 */
 697	0,  /* 1110 */
 698	0   /* 1111 */
 699};
 700
 701static inline void access_errorcf(unsigned int fs, struct frame *fp)
 702{
 703	unsigned long mmusr, addr;
 704	unsigned int err_code;
 705	int need_page_fault;
 706
 707	mmusr = mmu_read(MMUSR);
 708	addr = mmu_read(MMUAR);
 709
 710	/*
 711	 * error_code:
 712	 *	bit 0 == 0 means no page found, 1 means protection fault
 713	 *	bit 1 == 0 means read, 1 means write
 714	 */
 715	switch (fs) {
 716	case  5:  /* 0101 TLB opword X miss */
 717		need_page_fault = cf_tlb_miss(&fp->ptregs, 0, 0, 0);
 718		addr = fp->ptregs.pc;
 719		break;
 720	case  6:  /* 0110 TLB extension word X miss */
 721		need_page_fault = cf_tlb_miss(&fp->ptregs, 0, 0, 1);
 722		addr = fp->ptregs.pc + sizeof(long);
 723		break;
 724	case 10:  /* 1010 TLB W miss */
 725		need_page_fault = cf_tlb_miss(&fp->ptregs, 1, 1, 0);
 726		break;
 727	case 14: /* 1110 TLB R miss */
 728		need_page_fault = cf_tlb_miss(&fp->ptregs, 0, 1, 0);
 729		break;
 730	default:
 731		/* 0000 Normal  */
 732		/* 0001 Reserved */
 733		/* 0010 Interrupt during debug service routine */
 734		/* 0011 Reserved */
 735		/* 0100 X Protection */
 736		/* 0111 IFP in emulator mode */
 737		/* 1000 W Protection*/
 738		/* 1001 Write error*/
 739		/* 1011 Reserved*/
 740		/* 1100 R Protection*/
 741		/* 1101 R Protection*/
 742		/* 1111 OEP in emulator mode*/
 743		need_page_fault = 1;
 744		break;
 745	}
 746
 747	if (need_page_fault) {
 748		err_code = fs_err_code[fs];
 749		if ((fs == 13) && (mmusr & MMUSR_WF)) /* rd-mod-wr access */
 750			err_code |= 2; /* bit1 - write, bit0 - protection */
 751		do_page_fault(&fp->ptregs, addr, err_code);
 752	}
 753}
 754#endif /* CONFIG_COLDFIRE CONFIG_MMU */
 755
 756asmlinkage void buserr_c(struct frame *fp)
 757{
 758	/* Only set esp0 if coming from user mode */
 759	if (user_mode(&fp->ptregs))
 760		current->thread.esp0 = (unsigned long) fp;
 761
 762	pr_debug("*** Bus Error *** Format is %x\n", fp->ptregs.format);
 763
 764#if defined(CONFIG_COLDFIRE) && defined(CONFIG_MMU)
 765	if (CPU_IS_COLDFIRE) {
 766		unsigned int fs;
 767		fs = (fp->ptregs.vector & 0x3) |
 768			((fp->ptregs.vector & 0xc00) >> 8);
 769		switch (fs) {
 770		case 0x5:
 771		case 0x6:
 772		case 0x7:
 773		case 0x9:
 774		case 0xa:
 775		case 0xd:
 776		case 0xe:
 777		case 0xf:
 778			access_errorcf(fs, fp);
 779			return;
 780		default:
 781			break;
 782		}
 783	}
 784#endif /* CONFIG_COLDFIRE && CONFIG_MMU */
 785
 786	switch (fp->ptregs.format) {
 787#if defined (CONFIG_M68060)
 788	case 4:				/* 68060 access error */
 789	  access_error060 (fp);
 790	  break;
 791#endif
 792#if defined (CONFIG_M68040)
 793	case 0x7:			/* 68040 access error */
 794	  access_error040 (fp);
 795	  break;
 796#endif
 797#if defined (CPU_M68020_OR_M68030)
 798	case 0xa:
 799	case 0xb:
 800	  bus_error030 (fp);
 801	  break;
 802#endif
 803	default:
 804	  die_if_kernel("bad frame format",&fp->ptregs,0);
 805	  pr_debug("Unknown SIGSEGV - 4\n");
 806	  force_sig(SIGSEGV);
 807	}
 808}
 809
 810
 811static int kstack_depth_to_print = 48;
 812
 813static void show_trace(unsigned long *stack, const char *loglvl)
 814{
 815	unsigned long *endstack;
 816	unsigned long addr;
 817	int i;
 818
 819	printk("%sCall Trace:", loglvl);
 820	addr = (unsigned long)stack + THREAD_SIZE - 1;
 821	endstack = (unsigned long *)(addr & -THREAD_SIZE);
 822	i = 0;
 823	while (stack + 1 <= endstack) {
 824		addr = *stack++;
 825		/*
 826		 * If the address is either in the text segment of the
 827		 * kernel, or in the region which contains vmalloc'ed
 828		 * memory, it *may* be the address of a calling
 829		 * routine; if so, print it so that someone tracing
 830		 * down the cause of the crash will be able to figure
 831		 * out the call path that was taken.
 832		 */
 833		if (__kernel_text_address(addr)) {
 834#ifndef CONFIG_KALLSYMS
 835			if (i % 5 == 0)
 836				pr_cont("\n       ");
 837#endif
 838			pr_cont(" [<%08lx>] %pS\n", addr, (void *)addr);
 839			i++;
 840		}
 841	}
 842	pr_cont("\n");
 843}
 844
 845void show_registers(struct pt_regs *regs)
 846{
 847	struct frame *fp = (struct frame *)regs;
 848	mm_segment_t old_fs = get_fs();
 849	u16 c, *cp;
 850	unsigned long addr;
 851	int i;
 852
 853	print_modules();
 854	pr_info("PC: [<%08lx>] %pS\n", regs->pc, (void *)regs->pc);
 855	pr_info("SR: %04x  SP: %p  a2: %08lx\n", regs->sr, regs, regs->a2);
 856	pr_info("d0: %08lx    d1: %08lx    d2: %08lx    d3: %08lx\n",
 857	       regs->d0, regs->d1, regs->d2, regs->d3);
 858	pr_info("d4: %08lx    d5: %08lx    a0: %08lx    a1: %08lx\n",
 859	       regs->d4, regs->d5, regs->a0, regs->a1);
 860
 861	pr_info("Process %s (pid: %d, task=%p)\n",
 862		current->comm, task_pid_nr(current), current);
 863	addr = (unsigned long)&fp->un;
 864	pr_info("Frame format=%X ", regs->format);
 865	switch (regs->format) {
 866	case 0x2:
 867		pr_cont("instr addr=%08lx\n", fp->un.fmt2.iaddr);
 868		addr += sizeof(fp->un.fmt2);
 869		break;
 870	case 0x3:
 871		pr_cont("eff addr=%08lx\n", fp->un.fmt3.effaddr);
 872		addr += sizeof(fp->un.fmt3);
 873		break;
 874	case 0x4:
 875		if (CPU_IS_060)
 876			pr_cont("fault addr=%08lx fslw=%08lx\n",
 877				fp->un.fmt4.effaddr, fp->un.fmt4.pc);
 878		else
 879			pr_cont("eff addr=%08lx pc=%08lx\n",
 880				fp->un.fmt4.effaddr, fp->un.fmt4.pc);
 881		addr += sizeof(fp->un.fmt4);
 882		break;
 883	case 0x7:
 884		pr_cont("eff addr=%08lx ssw=%04x faddr=%08lx\n",
 885			fp->un.fmt7.effaddr, fp->un.fmt7.ssw, fp->un.fmt7.faddr);
 886		pr_info("wb 1 stat/addr/data: %04x %08lx %08lx\n",
 887			fp->un.fmt7.wb1s, fp->un.fmt7.wb1a, fp->un.fmt7.wb1dpd0);
 888		pr_info("wb 2 stat/addr/data: %04x %08lx %08lx\n",
 889			fp->un.fmt7.wb2s, fp->un.fmt7.wb2a, fp->un.fmt7.wb2d);
 890		pr_info("wb 3 stat/addr/data: %04x %08lx %08lx\n",
 891			fp->un.fmt7.wb3s, fp->un.fmt7.wb3a, fp->un.fmt7.wb3d);
 892		pr_info("push data: %08lx %08lx %08lx %08lx\n",
 893			fp->un.fmt7.wb1dpd0, fp->un.fmt7.pd1, fp->un.fmt7.pd2,
 894			fp->un.fmt7.pd3);
 895		addr += sizeof(fp->un.fmt7);
 896		break;
 897	case 0x9:
 898		pr_cont("instr addr=%08lx\n", fp->un.fmt9.iaddr);
 899		addr += sizeof(fp->un.fmt9);
 900		break;
 901	case 0xa:
 902		pr_cont("ssw=%04x isc=%04x isb=%04x daddr=%08lx dobuf=%08lx\n",
 903			fp->un.fmta.ssw, fp->un.fmta.isc, fp->un.fmta.isb,
 904			fp->un.fmta.daddr, fp->un.fmta.dobuf);
 905		addr += sizeof(fp->un.fmta);
 906		break;
 907	case 0xb:
 908		pr_cont("ssw=%04x isc=%04x isb=%04x daddr=%08lx dobuf=%08lx\n",
 909			fp->un.fmtb.ssw, fp->un.fmtb.isc, fp->un.fmtb.isb,
 910			fp->un.fmtb.daddr, fp->un.fmtb.dobuf);
 911		pr_info("baddr=%08lx dibuf=%08lx ver=%x\n",
 912			fp->un.fmtb.baddr, fp->un.fmtb.dibuf, fp->un.fmtb.ver);
 913		addr += sizeof(fp->un.fmtb);
 914		break;
 915	default:
 916		pr_cont("\n");
 917	}
 918	show_stack(NULL, (unsigned long *)addr, KERN_INFO);
 919
 920	pr_info("Code:");
 921	set_fs(KERNEL_DS);
 922	cp = (u16 *)regs->pc;
 923	for (i = -8; i < 16; i++) {
 924		if (get_user(c, cp + i) && i >= 0) {
 925			pr_cont(" Bad PC value.");
 926			break;
 927		}
 928		if (i)
 929			pr_cont(" %04x", c);
 930		else
 931			pr_cont(" <%04x>", c);
 932	}
 933	set_fs(old_fs);
 934	pr_cont("\n");
 935}
 936
 937void show_stack(struct task_struct *task, unsigned long *stack,
 938		const char *loglvl)
 939{
 940	unsigned long *p;
 941	unsigned long *endstack;
 942	int i;
 943
 944	if (!stack) {
 945		if (task)
 946			stack = (unsigned long *)task->thread.esp0;
 947		else
 948			stack = (unsigned long *)&stack;
 949	}
 950	endstack = (unsigned long *)(((unsigned long)stack + THREAD_SIZE - 1) & -THREAD_SIZE);
 951
 952	printk("%sStack from %08lx:", loglvl, (unsigned long)stack);
 953	p = stack;
 954	for (i = 0; i < kstack_depth_to_print; i++) {
 955		if (p + 1 > endstack)
 956			break;
 957		if (i % 8 == 0)
 958			pr_cont("\n       ");
 959		pr_cont(" %08lx", *p++);
 960	}
 961	pr_cont("\n");
 962	show_trace(stack, loglvl);
 963}
 964
 965/*
 966 * The vector number returned in the frame pointer may also contain
 967 * the "fs" (Fault Status) bits on ColdFire. These are in the bottom
 968 * 2 bits, and upper 2 bits. So we need to mask out the real vector
 969 * number before using it in comparisons. You don't need to do this on
 970 * real 68k parts, but it won't hurt either.
 971 */
 972
 973void bad_super_trap (struct frame *fp)
 974{
 975	int vector = (fp->ptregs.vector >> 2) & 0xff;
 976
 977	console_verbose();
 978	if (vector < ARRAY_SIZE(vec_names))
 979		pr_err("*** %s ***   FORMAT=%X\n",
 980			vec_names[vector],
 981			fp->ptregs.format);
 982	else
 983		pr_err("*** Exception %d ***   FORMAT=%X\n",
 984			vector, fp->ptregs.format);
 985	if (vector == VEC_ADDRERR && CPU_IS_020_OR_030) {
 986		unsigned short ssw = fp->un.fmtb.ssw;
 987
 988		pr_err("SSW=%#06x  ", ssw);
 989
 990		if (ssw & RC)
 991			pr_err("Pipe stage C instruction fault at %#010lx\n",
 992				(fp->ptregs.format) == 0xA ?
 993				fp->ptregs.pc + 2 : fp->un.fmtb.baddr - 2);
 994		if (ssw & RB)
 995			pr_err("Pipe stage B instruction fault at %#010lx\n",
 996				(fp->ptregs.format) == 0xA ?
 997				fp->ptregs.pc + 4 : fp->un.fmtb.baddr);
 998		if (ssw & DF)
 999			pr_err("Data %s fault at %#010lx in %s (pc=%#lx)\n",
1000				ssw & RW ? "read" : "write",
1001				fp->un.fmtb.daddr, space_names[ssw & DFC],
1002				fp->ptregs.pc);
1003	}
1004	pr_err("Current process id is %d\n", task_pid_nr(current));
1005	die_if_kernel("BAD KERNEL TRAP", &fp->ptregs, 0);
1006}
1007
1008asmlinkage void trap_c(struct frame *fp)
1009{
1010	int sig, si_code;
1011	void __user *addr;
1012	int vector = (fp->ptregs.vector >> 2) & 0xff;
1013
1014	if (fp->ptregs.sr & PS_S) {
1015		if (vector == VEC_TRACE) {
1016			/* traced a trapping instruction on a 68020/30,
1017			 * real exception will be executed afterwards.
1018			 */
1019			return;
1020		}
1021#ifdef CONFIG_MMU
1022		if (fixup_exception(&fp->ptregs))
1023			return;
1024#endif
1025		bad_super_trap(fp);
1026		return;
1027	}
1028
1029	/* send the appropriate signal to the user program */
1030	switch (vector) {
1031	    case VEC_ADDRERR:
1032		si_code = BUS_ADRALN;
1033		sig = SIGBUS;
1034		break;
1035	    case VEC_ILLEGAL:
1036	    case VEC_LINE10:
1037	    case VEC_LINE11:
1038		si_code = ILL_ILLOPC;
1039		sig = SIGILL;
1040		break;
1041	    case VEC_PRIV:
1042		si_code = ILL_PRVOPC;
1043		sig = SIGILL;
1044		break;
1045	    case VEC_COPROC:
1046		si_code = ILL_COPROC;
1047		sig = SIGILL;
1048		break;
1049	    case VEC_TRAP1:
1050	    case VEC_TRAP2:
1051	    case VEC_TRAP3:
1052	    case VEC_TRAP4:
1053	    case VEC_TRAP5:
1054	    case VEC_TRAP6:
1055	    case VEC_TRAP7:
1056	    case VEC_TRAP8:
1057	    case VEC_TRAP9:
1058	    case VEC_TRAP10:
1059	    case VEC_TRAP11:
1060	    case VEC_TRAP12:
1061	    case VEC_TRAP13:
1062	    case VEC_TRAP14:
1063		si_code = ILL_ILLTRP;
1064		sig = SIGILL;
1065		break;
1066	    case VEC_FPBRUC:
1067	    case VEC_FPOE:
1068	    case VEC_FPNAN:
1069		si_code = FPE_FLTINV;
1070		sig = SIGFPE;
1071		break;
1072	    case VEC_FPIR:
1073		si_code = FPE_FLTRES;
1074		sig = SIGFPE;
1075		break;
1076	    case VEC_FPDIVZ:
1077		si_code = FPE_FLTDIV;
1078		sig = SIGFPE;
1079		break;
1080	    case VEC_FPUNDER:
1081		si_code = FPE_FLTUND;
1082		sig = SIGFPE;
1083		break;
1084	    case VEC_FPOVER:
1085		si_code = FPE_FLTOVF;
1086		sig = SIGFPE;
1087		break;
1088	    case VEC_ZERODIV:
1089		si_code = FPE_INTDIV;
1090		sig = SIGFPE;
1091		break;
1092	    case VEC_CHK:
1093	    case VEC_TRAP:
1094		si_code = FPE_INTOVF;
1095		sig = SIGFPE;
1096		break;
1097	    case VEC_TRACE:		/* ptrace single step */
1098		si_code = TRAP_TRACE;
1099		sig = SIGTRAP;
1100		break;
1101	    case VEC_TRAP15:		/* breakpoint */
1102		si_code = TRAP_BRKPT;
1103		sig = SIGTRAP;
1104		break;
1105	    default:
1106		si_code = ILL_ILLOPC;
1107		sig = SIGILL;
1108		break;
1109	}
1110	switch (fp->ptregs.format) {
1111	    default:
1112		addr = (void __user *) fp->ptregs.pc;
1113		break;
1114	    case 2:
1115		addr = (void __user *) fp->un.fmt2.iaddr;
1116		break;
1117	    case 7:
1118		addr = (void __user *) fp->un.fmt7.effaddr;
1119		break;
1120	    case 9:
1121		addr = (void __user *) fp->un.fmt9.iaddr;
1122		break;
1123	    case 10:
1124		addr = (void __user *) fp->un.fmta.daddr;
1125		break;
1126	    case 11:
1127		addr = (void __user*) fp->un.fmtb.daddr;
1128		break;
1129	}
1130	force_sig_fault(sig, si_code, addr);
1131}
1132
1133void die_if_kernel (char *str, struct pt_regs *fp, int nr)
1134{
1135	if (!(fp->sr & PS_S))
1136		return;
1137
1138	console_verbose();
1139	pr_crit("%s: %08x\n", str, nr);
1140	show_registers(fp);
1141	add_taint(TAINT_DIE, LOCKDEP_NOW_UNRELIABLE);
1142	do_exit(SIGSEGV);
1143}
1144
1145asmlinkage void set_esp0(unsigned long ssp)
1146{
1147	current->thread.esp0 = ssp;
1148}
1149
1150/*
1151 * This function is called if an error occur while accessing
1152 * user-space from the fpsp040 code.
1153 */
1154asmlinkage void fpsp040_die(void)
1155{
1156	do_exit(SIGSEGV);
1157}
1158
1159#ifdef CONFIG_M68KFPU_EMU
1160asmlinkage void fpemu_signal(int signal, int code, void *addr)
1161{
1162	force_sig_fault(signal, code, addr);
1163}
1164#endif
v5.4
   1/*
   2 *  linux/arch/m68k/kernel/traps.c
   3 *
   4 *  Copyright (C) 1993, 1994 by Hamish Macdonald
   5 *
   6 *  68040 fixes by Michael Rausch
   7 *  68040 fixes by Martin Apel
   8 *  68040 fixes and writeback by Richard Zidlicky
   9 *  68060 fixes by Roman Hodek
  10 *  68060 fixes by Jesper Skov
  11 *
  12 * This file is subject to the terms and conditions of the GNU General Public
  13 * License.  See the file COPYING in the main directory of this archive
  14 * for more details.
  15 */
  16
  17/*
  18 * Sets up all exception vectors
  19 */
  20
  21#include <linux/sched.h>
  22#include <linux/sched/debug.h>
  23#include <linux/signal.h>
  24#include <linux/kernel.h>
  25#include <linux/mm.h>
  26#include <linux/module.h>
  27#include <linux/user.h>
  28#include <linux/string.h>
  29#include <linux/linkage.h>
  30#include <linux/init.h>
  31#include <linux/ptrace.h>
  32#include <linux/kallsyms.h>
  33
  34#include <asm/setup.h>
  35#include <asm/fpu.h>
  36#include <linux/uaccess.h>
  37#include <asm/traps.h>
  38#include <asm/pgalloc.h>
  39#include <asm/machdep.h>
  40#include <asm/siginfo.h>
  41
  42
  43static const char *vec_names[] = {
  44	[VEC_RESETSP]	= "RESET SP",
  45	[VEC_RESETPC]	= "RESET PC",
  46	[VEC_BUSERR]	= "BUS ERROR",
  47	[VEC_ADDRERR]	= "ADDRESS ERROR",
  48	[VEC_ILLEGAL]	= "ILLEGAL INSTRUCTION",
  49	[VEC_ZERODIV]	= "ZERO DIVIDE",
  50	[VEC_CHK]	= "CHK",
  51	[VEC_TRAP]	= "TRAPcc",
  52	[VEC_PRIV]	= "PRIVILEGE VIOLATION",
  53	[VEC_TRACE]	= "TRACE",
  54	[VEC_LINE10]	= "LINE 1010",
  55	[VEC_LINE11]	= "LINE 1111",
  56	[VEC_RESV12]	= "UNASSIGNED RESERVED 12",
  57	[VEC_COPROC]	= "COPROCESSOR PROTOCOL VIOLATION",
  58	[VEC_FORMAT]	= "FORMAT ERROR",
  59	[VEC_UNINT]	= "UNINITIALIZED INTERRUPT",
  60	[VEC_RESV16]	= "UNASSIGNED RESERVED 16",
  61	[VEC_RESV17]	= "UNASSIGNED RESERVED 17",
  62	[VEC_RESV18]	= "UNASSIGNED RESERVED 18",
  63	[VEC_RESV19]	= "UNASSIGNED RESERVED 19",
  64	[VEC_RESV20]	= "UNASSIGNED RESERVED 20",
  65	[VEC_RESV21]	= "UNASSIGNED RESERVED 21",
  66	[VEC_RESV22]	= "UNASSIGNED RESERVED 22",
  67	[VEC_RESV23]	= "UNASSIGNED RESERVED 23",
  68	[VEC_SPUR]	= "SPURIOUS INTERRUPT",
  69	[VEC_INT1]	= "LEVEL 1 INT",
  70	[VEC_INT2]	= "LEVEL 2 INT",
  71	[VEC_INT3]	= "LEVEL 3 INT",
  72	[VEC_INT4]	= "LEVEL 4 INT",
  73	[VEC_INT5]	= "LEVEL 5 INT",
  74	[VEC_INT6]	= "LEVEL 6 INT",
  75	[VEC_INT7]	= "LEVEL 7 INT",
  76	[VEC_SYS]	= "SYSCALL",
  77	[VEC_TRAP1]	= "TRAP #1",
  78	[VEC_TRAP2]	= "TRAP #2",
  79	[VEC_TRAP3]	= "TRAP #3",
  80	[VEC_TRAP4]	= "TRAP #4",
  81	[VEC_TRAP5]	= "TRAP #5",
  82	[VEC_TRAP6]	= "TRAP #6",
  83	[VEC_TRAP7]	= "TRAP #7",
  84	[VEC_TRAP8]	= "TRAP #8",
  85	[VEC_TRAP9]	= "TRAP #9",
  86	[VEC_TRAP10]	= "TRAP #10",
  87	[VEC_TRAP11]	= "TRAP #11",
  88	[VEC_TRAP12]	= "TRAP #12",
  89	[VEC_TRAP13]	= "TRAP #13",
  90	[VEC_TRAP14]	= "TRAP #14",
  91	[VEC_TRAP15]	= "TRAP #15",
  92	[VEC_FPBRUC]	= "FPCP BSUN",
  93	[VEC_FPIR]	= "FPCP INEXACT",
  94	[VEC_FPDIVZ]	= "FPCP DIV BY 0",
  95	[VEC_FPUNDER]	= "FPCP UNDERFLOW",
  96	[VEC_FPOE]	= "FPCP OPERAND ERROR",
  97	[VEC_FPOVER]	= "FPCP OVERFLOW",
  98	[VEC_FPNAN]	= "FPCP SNAN",
  99	[VEC_FPUNSUP]	= "FPCP UNSUPPORTED OPERATION",
 100	[VEC_MMUCFG]	= "MMU CONFIGURATION ERROR",
 101	[VEC_MMUILL]	= "MMU ILLEGAL OPERATION ERROR",
 102	[VEC_MMUACC]	= "MMU ACCESS LEVEL VIOLATION ERROR",
 103	[VEC_RESV59]	= "UNASSIGNED RESERVED 59",
 104	[VEC_UNIMPEA]	= "UNASSIGNED RESERVED 60",
 105	[VEC_UNIMPII]	= "UNASSIGNED RESERVED 61",
 106	[VEC_RESV62]	= "UNASSIGNED RESERVED 62",
 107	[VEC_RESV63]	= "UNASSIGNED RESERVED 63",
 108};
 109
 110static const char *space_names[] = {
 111	[0]		= "Space 0",
 112	[USER_DATA]	= "User Data",
 113	[USER_PROGRAM]	= "User Program",
 114#ifndef CONFIG_SUN3
 115	[3]		= "Space 3",
 116#else
 117	[FC_CONTROL]	= "Control",
 118#endif
 119	[4]		= "Space 4",
 120	[SUPER_DATA]	= "Super Data",
 121	[SUPER_PROGRAM]	= "Super Program",
 122	[CPU_SPACE]	= "CPU"
 123};
 124
 125void die_if_kernel(char *,struct pt_regs *,int);
 126asmlinkage int do_page_fault(struct pt_regs *regs, unsigned long address,
 127                             unsigned long error_code);
 128int send_fault_sig(struct pt_regs *regs);
 129
 130asmlinkage void trap_c(struct frame *fp);
 131
 132#if defined (CONFIG_M68060)
 133static inline void access_error060 (struct frame *fp)
 134{
 135	unsigned long fslw = fp->un.fmt4.pc; /* is really FSLW for access error */
 136
 137	pr_debug("fslw=%#lx, fa=%#lx\n", fslw, fp->un.fmt4.effaddr);
 138
 139	if (fslw & MMU060_BPE) {
 140		/* branch prediction error -> clear branch cache */
 141		__asm__ __volatile__ ("movec %/cacr,%/d0\n\t"
 142				      "orl   #0x00400000,%/d0\n\t"
 143				      "movec %/d0,%/cacr"
 144				      : : : "d0" );
 145		/* return if there's no other error */
 146		if (!(fslw & MMU060_ERR_BITS) && !(fslw & MMU060_SEE))
 147			return;
 148	}
 149
 150	if (fslw & (MMU060_DESC_ERR | MMU060_WP | MMU060_SP)) {
 151		unsigned long errorcode;
 152		unsigned long addr = fp->un.fmt4.effaddr;
 153
 154		if (fslw & MMU060_MA)
 155			addr = (addr + PAGE_SIZE - 1) & PAGE_MASK;
 156
 157		errorcode = 1;
 158		if (fslw & MMU060_DESC_ERR) {
 159			__flush_tlb040_one(addr);
 160			errorcode = 0;
 161		}
 162		if (fslw & MMU060_W)
 163			errorcode |= 2;
 164		pr_debug("errorcode = %ld\n", errorcode);
 165		do_page_fault(&fp->ptregs, addr, errorcode);
 166	} else if (fslw & (MMU060_SEE)){
 167		/* Software Emulation Error.
 168		 * fault during mem_read/mem_write in ifpsp060/os.S
 169		 */
 170		send_fault_sig(&fp->ptregs);
 171	} else if (!(fslw & (MMU060_RE|MMU060_WE)) ||
 172		   send_fault_sig(&fp->ptregs) > 0) {
 173		pr_err("pc=%#lx, fa=%#lx\n", fp->ptregs.pc,
 174		       fp->un.fmt4.effaddr);
 175		pr_err("68060 access error, fslw=%lx\n", fslw);
 176		trap_c( fp );
 177	}
 178}
 179#endif /* CONFIG_M68060 */
 180
 181#if defined (CONFIG_M68040)
 182static inline unsigned long probe040(int iswrite, unsigned long addr, int wbs)
 183{
 184	unsigned long mmusr;
 185	mm_segment_t old_fs = get_fs();
 186
 187	set_fs(MAKE_MM_SEG(wbs));
 188
 189	if (iswrite)
 190		asm volatile (".chip 68040; ptestw (%0); .chip 68k" : : "a" (addr));
 191	else
 192		asm volatile (".chip 68040; ptestr (%0); .chip 68k" : : "a" (addr));
 193
 194	asm volatile (".chip 68040; movec %%mmusr,%0; .chip 68k" : "=r" (mmusr));
 195
 196	set_fs(old_fs);
 197
 198	return mmusr;
 199}
 200
 201static inline int do_040writeback1(unsigned short wbs, unsigned long wba,
 202				   unsigned long wbd)
 203{
 204	int res = 0;
 205	mm_segment_t old_fs = get_fs();
 206
 207	/* set_fs can not be moved, otherwise put_user() may oops */
 208	set_fs(MAKE_MM_SEG(wbs));
 209
 210	switch (wbs & WBSIZ_040) {
 211	case BA_SIZE_BYTE:
 212		res = put_user(wbd & 0xff, (char __user *)wba);
 213		break;
 214	case BA_SIZE_WORD:
 215		res = put_user(wbd & 0xffff, (short __user *)wba);
 216		break;
 217	case BA_SIZE_LONG:
 218		res = put_user(wbd, (int __user *)wba);
 219		break;
 220	}
 221
 222	/* set_fs can not be moved, otherwise put_user() may oops */
 223	set_fs(old_fs);
 224
 225
 226	pr_debug("do_040writeback1, res=%d\n", res);
 227
 228	return res;
 229}
 230
 231/* after an exception in a writeback the stack frame corresponding
 232 * to that exception is discarded, set a few bits in the old frame
 233 * to simulate what it should look like
 234 */
 235static inline void fix_xframe040(struct frame *fp, unsigned long wba, unsigned short wbs)
 236{
 237	fp->un.fmt7.faddr = wba;
 238	fp->un.fmt7.ssw = wbs & 0xff;
 239	if (wba != current->thread.faddr)
 240	    fp->un.fmt7.ssw |= MA_040;
 241}
 242
 243static inline void do_040writebacks(struct frame *fp)
 244{
 245	int res = 0;
 246#if 0
 247	if (fp->un.fmt7.wb1s & WBV_040)
 248		pr_err("access_error040: cannot handle 1st writeback. oops.\n");
 249#endif
 250
 251	if ((fp->un.fmt7.wb2s & WBV_040) &&
 252	    !(fp->un.fmt7.wb2s & WBTT_040)) {
 253		res = do_040writeback1(fp->un.fmt7.wb2s, fp->un.fmt7.wb2a,
 254				       fp->un.fmt7.wb2d);
 255		if (res)
 256			fix_xframe040(fp, fp->un.fmt7.wb2a, fp->un.fmt7.wb2s);
 257		else
 258			fp->un.fmt7.wb2s = 0;
 259	}
 260
 261	/* do the 2nd wb only if the first one was successful (except for a kernel wb) */
 262	if (fp->un.fmt7.wb3s & WBV_040 && (!res || fp->un.fmt7.wb3s & 4)) {
 263		res = do_040writeback1(fp->un.fmt7.wb3s, fp->un.fmt7.wb3a,
 264				       fp->un.fmt7.wb3d);
 265		if (res)
 266		    {
 267			fix_xframe040(fp, fp->un.fmt7.wb3a, fp->un.fmt7.wb3s);
 268
 269			fp->un.fmt7.wb2s = fp->un.fmt7.wb3s;
 270			fp->un.fmt7.wb3s &= (~WBV_040);
 271			fp->un.fmt7.wb2a = fp->un.fmt7.wb3a;
 272			fp->un.fmt7.wb2d = fp->un.fmt7.wb3d;
 273		    }
 274		else
 275			fp->un.fmt7.wb3s = 0;
 276	}
 277
 278	if (res)
 279		send_fault_sig(&fp->ptregs);
 280}
 281
 282/*
 283 * called from sigreturn(), must ensure userspace code didn't
 284 * manipulate exception frame to circumvent protection, then complete
 285 * pending writebacks
 286 * we just clear TM2 to turn it into a userspace access
 287 */
 288asmlinkage void berr_040cleanup(struct frame *fp)
 289{
 290	fp->un.fmt7.wb2s &= ~4;
 291	fp->un.fmt7.wb3s &= ~4;
 292
 293	do_040writebacks(fp);
 294}
 295
 296static inline void access_error040(struct frame *fp)
 297{
 298	unsigned short ssw = fp->un.fmt7.ssw;
 299	unsigned long mmusr;
 300
 301	pr_debug("ssw=%#x, fa=%#lx\n", ssw, fp->un.fmt7.faddr);
 302	pr_debug("wb1s=%#x, wb2s=%#x, wb3s=%#x\n", fp->un.fmt7.wb1s,
 303		fp->un.fmt7.wb2s, fp->un.fmt7.wb3s);
 304	pr_debug("wb2a=%lx, wb3a=%lx, wb2d=%lx, wb3d=%lx\n",
 305		fp->un.fmt7.wb2a, fp->un.fmt7.wb3a,
 306		fp->un.fmt7.wb2d, fp->un.fmt7.wb3d);
 307
 308	if (ssw & ATC_040) {
 309		unsigned long addr = fp->un.fmt7.faddr;
 310		unsigned long errorcode;
 311
 312		/*
 313		 * The MMU status has to be determined AFTER the address
 314		 * has been corrected if there was a misaligned access (MA).
 315		 */
 316		if (ssw & MA_040)
 317			addr = (addr + 7) & -8;
 318
 319		/* MMU error, get the MMUSR info for this access */
 320		mmusr = probe040(!(ssw & RW_040), addr, ssw);
 321		pr_debug("mmusr = %lx\n", mmusr);
 322		errorcode = 1;
 323		if (!(mmusr & MMU_R_040)) {
 324			/* clear the invalid atc entry */
 325			__flush_tlb040_one(addr);
 326			errorcode = 0;
 327		}
 328
 329		/* despite what documentation seems to say, RMW
 330		 * accesses have always both the LK and RW bits set */
 331		if (!(ssw & RW_040) || (ssw & LK_040))
 332			errorcode |= 2;
 333
 334		if (do_page_fault(&fp->ptregs, addr, errorcode)) {
 335			pr_debug("do_page_fault() !=0\n");
 336			if (user_mode(&fp->ptregs)){
 337				/* delay writebacks after signal delivery */
 338				pr_debug(".. was usermode - return\n");
 339				return;
 340			}
 341			/* disable writeback into user space from kernel
 342			 * (if do_page_fault didn't fix the mapping,
 343                         * the writeback won't do good)
 344			 */
 345disable_wb:
 346			pr_debug(".. disabling wb2\n");
 347			if (fp->un.fmt7.wb2a == fp->un.fmt7.faddr)
 348				fp->un.fmt7.wb2s &= ~WBV_040;
 349			if (fp->un.fmt7.wb3a == fp->un.fmt7.faddr)
 350				fp->un.fmt7.wb3s &= ~WBV_040;
 351		}
 352	} else {
 353		/* In case of a bus error we either kill the process or expect
 354		 * the kernel to catch the fault, which then is also responsible
 355		 * for cleaning up the mess.
 356		 */
 357		current->thread.signo = SIGBUS;
 358		current->thread.faddr = fp->un.fmt7.faddr;
 359		if (send_fault_sig(&fp->ptregs) >= 0)
 360			pr_err("68040 bus error (ssw=%x, faddr=%lx)\n", ssw,
 361			       fp->un.fmt7.faddr);
 362		goto disable_wb;
 363	}
 364
 365	do_040writebacks(fp);
 366}
 367#endif /* CONFIG_M68040 */
 368
 369#if defined(CONFIG_SUN3)
 370#include <asm/sun3mmu.h>
 371
 372extern int mmu_emu_handle_fault (unsigned long, int, int);
 373
 374/* sun3 version of bus_error030 */
 375
 376static inline void bus_error030 (struct frame *fp)
 377{
 378	unsigned char buserr_type = sun3_get_buserr ();
 379	unsigned long addr, errorcode;
 380	unsigned short ssw = fp->un.fmtb.ssw;
 381	extern unsigned long _sun3_map_test_start, _sun3_map_test_end;
 382
 383	if (ssw & (FC | FB))
 384		pr_debug("Instruction fault at %#010lx\n",
 385			ssw & FC ?
 386			fp->ptregs.format == 0xa ? fp->ptregs.pc + 2 : fp->un.fmtb.baddr - 2
 387			:
 388			fp->ptregs.format == 0xa ? fp->ptregs.pc + 4 : fp->un.fmtb.baddr);
 389	if (ssw & DF)
 390		pr_debug("Data %s fault at %#010lx in %s (pc=%#lx)\n",
 391			ssw & RW ? "read" : "write",
 392			fp->un.fmtb.daddr,
 393			space_names[ssw & DFC], fp->ptregs.pc);
 394
 395	/*
 396	 * Check if this page should be demand-mapped. This needs to go before
 397	 * the testing for a bad kernel-space access (demand-mapping applies
 398	 * to kernel accesses too).
 399	 */
 400
 401	if ((ssw & DF)
 402	    && (buserr_type & (SUN3_BUSERR_PROTERR | SUN3_BUSERR_INVALID))) {
 403		if (mmu_emu_handle_fault (fp->un.fmtb.daddr, ssw & RW, 0))
 404			return;
 405	}
 406
 407	/* Check for kernel-space pagefault (BAD). */
 408	if (fp->ptregs.sr & PS_S) {
 409		/* kernel fault must be a data fault to user space */
 410		if (! ((ssw & DF) && ((ssw & DFC) == USER_DATA))) {
 411		     // try checking the kernel mappings before surrender
 412		     if (mmu_emu_handle_fault (fp->un.fmtb.daddr, ssw & RW, 1))
 413			  return;
 414			/* instruction fault or kernel data fault! */
 415			if (ssw & (FC | FB))
 416				pr_err("Instruction fault at %#010lx\n",
 417					fp->ptregs.pc);
 418			if (ssw & DF) {
 419				/* was this fault incurred testing bus mappings? */
 420				if((fp->ptregs.pc >= (unsigned long)&_sun3_map_test_start) &&
 421				   (fp->ptregs.pc <= (unsigned long)&_sun3_map_test_end)) {
 422					send_fault_sig(&fp->ptregs);
 423					return;
 424				}
 425
 426				pr_err("Data %s fault at %#010lx in %s (pc=%#lx)\n",
 427					ssw & RW ? "read" : "write",
 428					fp->un.fmtb.daddr,
 429					space_names[ssw & DFC], fp->ptregs.pc);
 430			}
 431			pr_err("BAD KERNEL BUSERR\n");
 432
 433			die_if_kernel("Oops", &fp->ptregs,0);
 434			force_sig(SIGKILL);
 435			return;
 436		}
 437	} else {
 438		/* user fault */
 439		if (!(ssw & (FC | FB)) && !(ssw & DF))
 440			/* not an instruction fault or data fault! BAD */
 441			panic ("USER BUSERR w/o instruction or data fault");
 442	}
 443
 444
 445	/* First handle the data fault, if any.  */
 446	if (ssw & DF) {
 447		addr = fp->un.fmtb.daddr;
 448
 449// errorcode bit 0:	0 -> no page		1 -> protection fault
 450// errorcode bit 1:	0 -> read fault		1 -> write fault
 451
 452// (buserr_type & SUN3_BUSERR_PROTERR)	-> protection fault
 453// (buserr_type & SUN3_BUSERR_INVALID)	-> invalid page fault
 454
 455		if (buserr_type & SUN3_BUSERR_PROTERR)
 456			errorcode = 0x01;
 457		else if (buserr_type & SUN3_BUSERR_INVALID)
 458			errorcode = 0x00;
 459		else {
 460			pr_debug("*** unexpected busfault type=%#04x\n",
 461				 buserr_type);
 462			pr_debug("invalid %s access at %#lx from pc %#lx\n",
 463				 !(ssw & RW) ? "write" : "read", addr,
 464				 fp->ptregs.pc);
 465			die_if_kernel ("Oops", &fp->ptregs, buserr_type);
 466			force_sig (SIGBUS);
 467			return;
 468		}
 469
 470//todo: wtf is RM bit? --m
 471		if (!(ssw & RW) || ssw & RM)
 472			errorcode |= 0x02;
 473
 474		/* Handle page fault. */
 475		do_page_fault (&fp->ptregs, addr, errorcode);
 476
 477		/* Retry the data fault now. */
 478		return;
 479	}
 480
 481	/* Now handle the instruction fault. */
 482
 483	/* Get the fault address. */
 484	if (fp->ptregs.format == 0xA)
 485		addr = fp->ptregs.pc + 4;
 486	else
 487		addr = fp->un.fmtb.baddr;
 488	if (ssw & FC)
 489		addr -= 2;
 490
 491	if (buserr_type & SUN3_BUSERR_INVALID) {
 492		if (!mmu_emu_handle_fault(addr, 1, 0))
 493			do_page_fault (&fp->ptregs, addr, 0);
 494       } else {
 495		pr_debug("protection fault on insn access (segv).\n");
 496		force_sig (SIGSEGV);
 497       }
 498}
 499#else
 500#if defined(CPU_M68020_OR_M68030)
 501static inline void bus_error030 (struct frame *fp)
 502{
 503	volatile unsigned short temp;
 504	unsigned short mmusr;
 505	unsigned long addr, errorcode;
 506	unsigned short ssw = fp->un.fmtb.ssw;
 507#ifdef DEBUG
 508	unsigned long desc;
 509#endif
 510
 511	pr_debug("pid = %x  ", current->pid);
 512	pr_debug("SSW=%#06x  ", ssw);
 513
 514	if (ssw & (FC | FB))
 515		pr_debug("Instruction fault at %#010lx\n",
 516			ssw & FC ?
 517			fp->ptregs.format == 0xa ? fp->ptregs.pc + 2 : fp->un.fmtb.baddr - 2
 518			:
 519			fp->ptregs.format == 0xa ? fp->ptregs.pc + 4 : fp->un.fmtb.baddr);
 520	if (ssw & DF)
 521		pr_debug("Data %s fault at %#010lx in %s (pc=%#lx)\n",
 522			ssw & RW ? "read" : "write",
 523			fp->un.fmtb.daddr,
 524			space_names[ssw & DFC], fp->ptregs.pc);
 525
 526	/* ++andreas: If a data fault and an instruction fault happen
 527	   at the same time map in both pages.  */
 528
 529	/* First handle the data fault, if any.  */
 530	if (ssw & DF) {
 531		addr = fp->un.fmtb.daddr;
 532
 533#ifdef DEBUG
 534		asm volatile ("ptestr %3,%2@,#7,%0\n\t"
 535			      "pmove %%psr,%1"
 536			      : "=a&" (desc), "=m" (temp)
 537			      : "a" (addr), "d" (ssw));
 538		pr_debug("mmusr is %#x for addr %#lx in task %p\n",
 539			 temp, addr, current);
 540		pr_debug("descriptor address is 0x%p, contents %#lx\n",
 541			 __va(desc), *(unsigned long *)__va(desc));
 542#else
 543		asm volatile ("ptestr %2,%1@,#7\n\t"
 544			      "pmove %%psr,%0"
 545			      : "=m" (temp) : "a" (addr), "d" (ssw));
 546#endif
 547		mmusr = temp;
 548		errorcode = (mmusr & MMU_I) ? 0 : 1;
 549		if (!(ssw & RW) || (ssw & RM))
 550			errorcode |= 2;
 551
 552		if (mmusr & (MMU_I | MMU_WP)) {
 553			if (ssw & 4) {
 554				pr_err("Data %s fault at %#010lx in %s (pc=%#lx)\n",
 555				       ssw & RW ? "read" : "write",
 556				       fp->un.fmtb.daddr,
 557				       space_names[ssw & DFC], fp->ptregs.pc);
 558				goto buserr;
 559			}
 560			/* Don't try to do anything further if an exception was
 561			   handled. */
 562			if (do_page_fault (&fp->ptregs, addr, errorcode) < 0)
 563				return;
 564		} else if (!(mmusr & MMU_I)) {
 565			/* probably a 020 cas fault */
 566			if (!(ssw & RM) && send_fault_sig(&fp->ptregs) > 0)
 567				pr_err("unexpected bus error (%#x,%#x)\n", ssw,
 568				       mmusr);
 569		} else if (mmusr & (MMU_B|MMU_L|MMU_S)) {
 570			pr_err("invalid %s access at %#lx from pc %#lx\n",
 571			       !(ssw & RW) ? "write" : "read", addr,
 572			       fp->ptregs.pc);
 573			die_if_kernel("Oops",&fp->ptregs,mmusr);
 574			force_sig(SIGSEGV);
 575			return;
 576		} else {
 577#if 0
 578			static volatile long tlong;
 579#endif
 580
 581			pr_err("weird %s access at %#lx from pc %#lx (ssw is %#x)\n",
 582			       !(ssw & RW) ? "write" : "read", addr,
 583			       fp->ptregs.pc, ssw);
 584			asm volatile ("ptestr #1,%1@,#0\n\t"
 585				      "pmove %%psr,%0"
 586				      : "=m" (temp)
 587				      : "a" (addr));
 588			mmusr = temp;
 589
 590			pr_err("level 0 mmusr is %#x\n", mmusr);
 591#if 0
 592			asm volatile ("pmove %%tt0,%0"
 593				      : "=m" (tlong));
 594			pr_debug("tt0 is %#lx, ", tlong);
 595			asm volatile ("pmove %%tt1,%0"
 596				      : "=m" (tlong));
 597			pr_debug("tt1 is %#lx\n", tlong);
 598#endif
 599			pr_debug("Unknown SIGSEGV - 1\n");
 600			die_if_kernel("Oops",&fp->ptregs,mmusr);
 601			force_sig(SIGSEGV);
 602			return;
 603		}
 604
 605		/* setup an ATC entry for the access about to be retried */
 606		if (!(ssw & RW) || (ssw & RM))
 607			asm volatile ("ploadw %1,%0@" : /* no outputs */
 608				      : "a" (addr), "d" (ssw));
 609		else
 610			asm volatile ("ploadr %1,%0@" : /* no outputs */
 611				      : "a" (addr), "d" (ssw));
 612	}
 613
 614	/* Now handle the instruction fault. */
 615
 616	if (!(ssw & (FC|FB)))
 617		return;
 618
 619	if (fp->ptregs.sr & PS_S) {
 620		pr_err("Instruction fault at %#010lx\n", fp->ptregs.pc);
 621	buserr:
 622		pr_err("BAD KERNEL BUSERR\n");
 623		die_if_kernel("Oops",&fp->ptregs,0);
 624		force_sig(SIGKILL);
 625		return;
 626	}
 627
 628	/* get the fault address */
 629	if (fp->ptregs.format == 10)
 630		addr = fp->ptregs.pc + 4;
 631	else
 632		addr = fp->un.fmtb.baddr;
 633	if (ssw & FC)
 634		addr -= 2;
 635
 636	if ((ssw & DF) && ((addr ^ fp->un.fmtb.daddr) & PAGE_MASK) == 0)
 637		/* Insn fault on same page as data fault.  But we
 638		   should still create the ATC entry.  */
 639		goto create_atc_entry;
 640
 641#ifdef DEBUG
 642	asm volatile ("ptestr #1,%2@,#7,%0\n\t"
 643		      "pmove %%psr,%1"
 644		      : "=a&" (desc), "=m" (temp)
 645		      : "a" (addr));
 646	pr_debug("mmusr is %#x for addr %#lx in task %p\n",
 647		temp, addr, current);
 648	pr_debug("descriptor address is 0x%p, contents %#lx\n",
 649		__va(desc), *(unsigned long *)__va(desc));
 650#else
 651	asm volatile ("ptestr #1,%1@,#7\n\t"
 652		      "pmove %%psr,%0"
 653		      : "=m" (temp) : "a" (addr));
 654#endif
 655	mmusr = temp;
 656	if (mmusr & MMU_I)
 657		do_page_fault (&fp->ptregs, addr, 0);
 658	else if (mmusr & (MMU_B|MMU_L|MMU_S)) {
 659		pr_err("invalid insn access at %#lx from pc %#lx\n",
 660			addr, fp->ptregs.pc);
 661		pr_debug("Unknown SIGSEGV - 2\n");
 662		die_if_kernel("Oops",&fp->ptregs,mmusr);
 663		force_sig(SIGSEGV);
 664		return;
 665	}
 666
 667create_atc_entry:
 668	/* setup an ATC entry for the access about to be retried */
 669	asm volatile ("ploadr #2,%0@" : /* no outputs */
 670		      : "a" (addr));
 671}
 672#endif /* CPU_M68020_OR_M68030 */
 673#endif /* !CONFIG_SUN3 */
 674
 675#if defined(CONFIG_COLDFIRE) && defined(CONFIG_MMU)
 676#include <asm/mcfmmu.h>
 677
 678/*
 679 *	The following table converts the FS encoding of a ColdFire
 680 *	exception stack frame into the error_code value needed by
 681 *	do_fault.
 682*/
 683static const unsigned char fs_err_code[] = {
 684	0,  /* 0000 */
 685	0,  /* 0001 */
 686	0,  /* 0010 */
 687	0,  /* 0011 */
 688	1,  /* 0100 */
 689	0,  /* 0101 */
 690	0,  /* 0110 */
 691	0,  /* 0111 */
 692	2,  /* 1000 */
 693	3,  /* 1001 */
 694	2,  /* 1010 */
 695	0,  /* 1011 */
 696	1,  /* 1100 */
 697	1,  /* 1101 */
 698	0,  /* 1110 */
 699	0   /* 1111 */
 700};
 701
 702static inline void access_errorcf(unsigned int fs, struct frame *fp)
 703{
 704	unsigned long mmusr, addr;
 705	unsigned int err_code;
 706	int need_page_fault;
 707
 708	mmusr = mmu_read(MMUSR);
 709	addr = mmu_read(MMUAR);
 710
 711	/*
 712	 * error_code:
 713	 *	bit 0 == 0 means no page found, 1 means protection fault
 714	 *	bit 1 == 0 means read, 1 means write
 715	 */
 716	switch (fs) {
 717	case  5:  /* 0101 TLB opword X miss */
 718		need_page_fault = cf_tlb_miss(&fp->ptregs, 0, 0, 0);
 719		addr = fp->ptregs.pc;
 720		break;
 721	case  6:  /* 0110 TLB extension word X miss */
 722		need_page_fault = cf_tlb_miss(&fp->ptregs, 0, 0, 1);
 723		addr = fp->ptregs.pc + sizeof(long);
 724		break;
 725	case 10:  /* 1010 TLB W miss */
 726		need_page_fault = cf_tlb_miss(&fp->ptregs, 1, 1, 0);
 727		break;
 728	case 14: /* 1110 TLB R miss */
 729		need_page_fault = cf_tlb_miss(&fp->ptregs, 0, 1, 0);
 730		break;
 731	default:
 732		/* 0000 Normal  */
 733		/* 0001 Reserved */
 734		/* 0010 Interrupt during debug service routine */
 735		/* 0011 Reserved */
 736		/* 0100 X Protection */
 737		/* 0111 IFP in emulator mode */
 738		/* 1000 W Protection*/
 739		/* 1001 Write error*/
 740		/* 1011 Reserved*/
 741		/* 1100 R Protection*/
 742		/* 1101 R Protection*/
 743		/* 1111 OEP in emulator mode*/
 744		need_page_fault = 1;
 745		break;
 746	}
 747
 748	if (need_page_fault) {
 749		err_code = fs_err_code[fs];
 750		if ((fs == 13) && (mmusr & MMUSR_WF)) /* rd-mod-wr access */
 751			err_code |= 2; /* bit1 - write, bit0 - protection */
 752		do_page_fault(&fp->ptregs, addr, err_code);
 753	}
 754}
 755#endif /* CONFIG_COLDFIRE CONFIG_MMU */
 756
 757asmlinkage void buserr_c(struct frame *fp)
 758{
 759	/* Only set esp0 if coming from user mode */
 760	if (user_mode(&fp->ptregs))
 761		current->thread.esp0 = (unsigned long) fp;
 762
 763	pr_debug("*** Bus Error *** Format is %x\n", fp->ptregs.format);
 764
 765#if defined(CONFIG_COLDFIRE) && defined(CONFIG_MMU)
 766	if (CPU_IS_COLDFIRE) {
 767		unsigned int fs;
 768		fs = (fp->ptregs.vector & 0x3) |
 769			((fp->ptregs.vector & 0xc00) >> 8);
 770		switch (fs) {
 771		case 0x5:
 772		case 0x6:
 773		case 0x7:
 774		case 0x9:
 775		case 0xa:
 776		case 0xd:
 777		case 0xe:
 778		case 0xf:
 779			access_errorcf(fs, fp);
 780			return;
 781		default:
 782			break;
 783		}
 784	}
 785#endif /* CONFIG_COLDFIRE && CONFIG_MMU */
 786
 787	switch (fp->ptregs.format) {
 788#if defined (CONFIG_M68060)
 789	case 4:				/* 68060 access error */
 790	  access_error060 (fp);
 791	  break;
 792#endif
 793#if defined (CONFIG_M68040)
 794	case 0x7:			/* 68040 access error */
 795	  access_error040 (fp);
 796	  break;
 797#endif
 798#if defined (CPU_M68020_OR_M68030)
 799	case 0xa:
 800	case 0xb:
 801	  bus_error030 (fp);
 802	  break;
 803#endif
 804	default:
 805	  die_if_kernel("bad frame format",&fp->ptregs,0);
 806	  pr_debug("Unknown SIGSEGV - 4\n");
 807	  force_sig(SIGSEGV);
 808	}
 809}
 810
 811
 812static int kstack_depth_to_print = 48;
 813
 814void show_trace(unsigned long *stack)
 815{
 816	unsigned long *endstack;
 817	unsigned long addr;
 818	int i;
 819
 820	pr_info("Call Trace:");
 821	addr = (unsigned long)stack + THREAD_SIZE - 1;
 822	endstack = (unsigned long *)(addr & -THREAD_SIZE);
 823	i = 0;
 824	while (stack + 1 <= endstack) {
 825		addr = *stack++;
 826		/*
 827		 * If the address is either in the text segment of the
 828		 * kernel, or in the region which contains vmalloc'ed
 829		 * memory, it *may* be the address of a calling
 830		 * routine; if so, print it so that someone tracing
 831		 * down the cause of the crash will be able to figure
 832		 * out the call path that was taken.
 833		 */
 834		if (__kernel_text_address(addr)) {
 835#ifndef CONFIG_KALLSYMS
 836			if (i % 5 == 0)
 837				pr_cont("\n       ");
 838#endif
 839			pr_cont(" [<%08lx>] %pS\n", addr, (void *)addr);
 840			i++;
 841		}
 842	}
 843	pr_cont("\n");
 844}
 845
 846void show_registers(struct pt_regs *regs)
 847{
 848	struct frame *fp = (struct frame *)regs;
 849	mm_segment_t old_fs = get_fs();
 850	u16 c, *cp;
 851	unsigned long addr;
 852	int i;
 853
 854	print_modules();
 855	pr_info("PC: [<%08lx>] %pS\n", regs->pc, (void *)regs->pc);
 856	pr_info("SR: %04x  SP: %p  a2: %08lx\n", regs->sr, regs, regs->a2);
 857	pr_info("d0: %08lx    d1: %08lx    d2: %08lx    d3: %08lx\n",
 858	       regs->d0, regs->d1, regs->d2, regs->d3);
 859	pr_info("d4: %08lx    d5: %08lx    a0: %08lx    a1: %08lx\n",
 860	       regs->d4, regs->d5, regs->a0, regs->a1);
 861
 862	pr_info("Process %s (pid: %d, task=%p)\n",
 863		current->comm, task_pid_nr(current), current);
 864	addr = (unsigned long)&fp->un;
 865	pr_info("Frame format=%X ", regs->format);
 866	switch (regs->format) {
 867	case 0x2:
 868		pr_cont("instr addr=%08lx\n", fp->un.fmt2.iaddr);
 869		addr += sizeof(fp->un.fmt2);
 870		break;
 871	case 0x3:
 872		pr_cont("eff addr=%08lx\n", fp->un.fmt3.effaddr);
 873		addr += sizeof(fp->un.fmt3);
 874		break;
 875	case 0x4:
 876		if (CPU_IS_060)
 877			pr_cont("fault addr=%08lx fslw=%08lx\n",
 878				fp->un.fmt4.effaddr, fp->un.fmt4.pc);
 879		else
 880			pr_cont("eff addr=%08lx pc=%08lx\n",
 881				fp->un.fmt4.effaddr, fp->un.fmt4.pc);
 882		addr += sizeof(fp->un.fmt4);
 883		break;
 884	case 0x7:
 885		pr_cont("eff addr=%08lx ssw=%04x faddr=%08lx\n",
 886			fp->un.fmt7.effaddr, fp->un.fmt7.ssw, fp->un.fmt7.faddr);
 887		pr_info("wb 1 stat/addr/data: %04x %08lx %08lx\n",
 888			fp->un.fmt7.wb1s, fp->un.fmt7.wb1a, fp->un.fmt7.wb1dpd0);
 889		pr_info("wb 2 stat/addr/data: %04x %08lx %08lx\n",
 890			fp->un.fmt7.wb2s, fp->un.fmt7.wb2a, fp->un.fmt7.wb2d);
 891		pr_info("wb 3 stat/addr/data: %04x %08lx %08lx\n",
 892			fp->un.fmt7.wb3s, fp->un.fmt7.wb3a, fp->un.fmt7.wb3d);
 893		pr_info("push data: %08lx %08lx %08lx %08lx\n",
 894			fp->un.fmt7.wb1dpd0, fp->un.fmt7.pd1, fp->un.fmt7.pd2,
 895			fp->un.fmt7.pd3);
 896		addr += sizeof(fp->un.fmt7);
 897		break;
 898	case 0x9:
 899		pr_cont("instr addr=%08lx\n", fp->un.fmt9.iaddr);
 900		addr += sizeof(fp->un.fmt9);
 901		break;
 902	case 0xa:
 903		pr_cont("ssw=%04x isc=%04x isb=%04x daddr=%08lx dobuf=%08lx\n",
 904			fp->un.fmta.ssw, fp->un.fmta.isc, fp->un.fmta.isb,
 905			fp->un.fmta.daddr, fp->un.fmta.dobuf);
 906		addr += sizeof(fp->un.fmta);
 907		break;
 908	case 0xb:
 909		pr_cont("ssw=%04x isc=%04x isb=%04x daddr=%08lx dobuf=%08lx\n",
 910			fp->un.fmtb.ssw, fp->un.fmtb.isc, fp->un.fmtb.isb,
 911			fp->un.fmtb.daddr, fp->un.fmtb.dobuf);
 912		pr_info("baddr=%08lx dibuf=%08lx ver=%x\n",
 913			fp->un.fmtb.baddr, fp->un.fmtb.dibuf, fp->un.fmtb.ver);
 914		addr += sizeof(fp->un.fmtb);
 915		break;
 916	default:
 917		pr_cont("\n");
 918	}
 919	show_stack(NULL, (unsigned long *)addr);
 920
 921	pr_info("Code:");
 922	set_fs(KERNEL_DS);
 923	cp = (u16 *)regs->pc;
 924	for (i = -8; i < 16; i++) {
 925		if (get_user(c, cp + i) && i >= 0) {
 926			pr_cont(" Bad PC value.");
 927			break;
 928		}
 929		if (i)
 930			pr_cont(" %04x", c);
 931		else
 932			pr_cont(" <%04x>", c);
 933	}
 934	set_fs(old_fs);
 935	pr_cont("\n");
 936}
 937
 938void show_stack(struct task_struct *task, unsigned long *stack)
 
 939{
 940	unsigned long *p;
 941	unsigned long *endstack;
 942	int i;
 943
 944	if (!stack) {
 945		if (task)
 946			stack = (unsigned long *)task->thread.esp0;
 947		else
 948			stack = (unsigned long *)&stack;
 949	}
 950	endstack = (unsigned long *)(((unsigned long)stack + THREAD_SIZE - 1) & -THREAD_SIZE);
 951
 952	pr_info("Stack from %08lx:", (unsigned long)stack);
 953	p = stack;
 954	for (i = 0; i < kstack_depth_to_print; i++) {
 955		if (p + 1 > endstack)
 956			break;
 957		if (i % 8 == 0)
 958			pr_cont("\n       ");
 959		pr_cont(" %08lx", *p++);
 960	}
 961	pr_cont("\n");
 962	show_trace(stack);
 963}
 964
 965/*
 966 * The vector number returned in the frame pointer may also contain
 967 * the "fs" (Fault Status) bits on ColdFire. These are in the bottom
 968 * 2 bits, and upper 2 bits. So we need to mask out the real vector
 969 * number before using it in comparisons. You don't need to do this on
 970 * real 68k parts, but it won't hurt either.
 971 */
 972
 973void bad_super_trap (struct frame *fp)
 974{
 975	int vector = (fp->ptregs.vector >> 2) & 0xff;
 976
 977	console_verbose();
 978	if (vector < ARRAY_SIZE(vec_names))
 979		pr_err("*** %s ***   FORMAT=%X\n",
 980			vec_names[vector],
 981			fp->ptregs.format);
 982	else
 983		pr_err("*** Exception %d ***   FORMAT=%X\n",
 984			vector, fp->ptregs.format);
 985	if (vector == VEC_ADDRERR && CPU_IS_020_OR_030) {
 986		unsigned short ssw = fp->un.fmtb.ssw;
 987
 988		pr_err("SSW=%#06x  ", ssw);
 989
 990		if (ssw & RC)
 991			pr_err("Pipe stage C instruction fault at %#010lx\n",
 992				(fp->ptregs.format) == 0xA ?
 993				fp->ptregs.pc + 2 : fp->un.fmtb.baddr - 2);
 994		if (ssw & RB)
 995			pr_err("Pipe stage B instruction fault at %#010lx\n",
 996				(fp->ptregs.format) == 0xA ?
 997				fp->ptregs.pc + 4 : fp->un.fmtb.baddr);
 998		if (ssw & DF)
 999			pr_err("Data %s fault at %#010lx in %s (pc=%#lx)\n",
1000				ssw & RW ? "read" : "write",
1001				fp->un.fmtb.daddr, space_names[ssw & DFC],
1002				fp->ptregs.pc);
1003	}
1004	pr_err("Current process id is %d\n", task_pid_nr(current));
1005	die_if_kernel("BAD KERNEL TRAP", &fp->ptregs, 0);
1006}
1007
1008asmlinkage void trap_c(struct frame *fp)
1009{
1010	int sig, si_code;
1011	void __user *addr;
1012	int vector = (fp->ptregs.vector >> 2) & 0xff;
1013
1014	if (fp->ptregs.sr & PS_S) {
1015		if (vector == VEC_TRACE) {
1016			/* traced a trapping instruction on a 68020/30,
1017			 * real exception will be executed afterwards.
1018			 */
1019			return;
1020		}
1021#ifdef CONFIG_MMU
1022		if (fixup_exception(&fp->ptregs))
1023			return;
1024#endif
1025		bad_super_trap(fp);
1026		return;
1027	}
1028
1029	/* send the appropriate signal to the user program */
1030	switch (vector) {
1031	    case VEC_ADDRERR:
1032		si_code = BUS_ADRALN;
1033		sig = SIGBUS;
1034		break;
1035	    case VEC_ILLEGAL:
1036	    case VEC_LINE10:
1037	    case VEC_LINE11:
1038		si_code = ILL_ILLOPC;
1039		sig = SIGILL;
1040		break;
1041	    case VEC_PRIV:
1042		si_code = ILL_PRVOPC;
1043		sig = SIGILL;
1044		break;
1045	    case VEC_COPROC:
1046		si_code = ILL_COPROC;
1047		sig = SIGILL;
1048		break;
1049	    case VEC_TRAP1:
1050	    case VEC_TRAP2:
1051	    case VEC_TRAP3:
1052	    case VEC_TRAP4:
1053	    case VEC_TRAP5:
1054	    case VEC_TRAP6:
1055	    case VEC_TRAP7:
1056	    case VEC_TRAP8:
1057	    case VEC_TRAP9:
1058	    case VEC_TRAP10:
1059	    case VEC_TRAP11:
1060	    case VEC_TRAP12:
1061	    case VEC_TRAP13:
1062	    case VEC_TRAP14:
1063		si_code = ILL_ILLTRP;
1064		sig = SIGILL;
1065		break;
1066	    case VEC_FPBRUC:
1067	    case VEC_FPOE:
1068	    case VEC_FPNAN:
1069		si_code = FPE_FLTINV;
1070		sig = SIGFPE;
1071		break;
1072	    case VEC_FPIR:
1073		si_code = FPE_FLTRES;
1074		sig = SIGFPE;
1075		break;
1076	    case VEC_FPDIVZ:
1077		si_code = FPE_FLTDIV;
1078		sig = SIGFPE;
1079		break;
1080	    case VEC_FPUNDER:
1081		si_code = FPE_FLTUND;
1082		sig = SIGFPE;
1083		break;
1084	    case VEC_FPOVER:
1085		si_code = FPE_FLTOVF;
1086		sig = SIGFPE;
1087		break;
1088	    case VEC_ZERODIV:
1089		si_code = FPE_INTDIV;
1090		sig = SIGFPE;
1091		break;
1092	    case VEC_CHK:
1093	    case VEC_TRAP:
1094		si_code = FPE_INTOVF;
1095		sig = SIGFPE;
1096		break;
1097	    case VEC_TRACE:		/* ptrace single step */
1098		si_code = TRAP_TRACE;
1099		sig = SIGTRAP;
1100		break;
1101	    case VEC_TRAP15:		/* breakpoint */
1102		si_code = TRAP_BRKPT;
1103		sig = SIGTRAP;
1104		break;
1105	    default:
1106		si_code = ILL_ILLOPC;
1107		sig = SIGILL;
1108		break;
1109	}
1110	switch (fp->ptregs.format) {
1111	    default:
1112		addr = (void __user *) fp->ptregs.pc;
1113		break;
1114	    case 2:
1115		addr = (void __user *) fp->un.fmt2.iaddr;
1116		break;
1117	    case 7:
1118		addr = (void __user *) fp->un.fmt7.effaddr;
1119		break;
1120	    case 9:
1121		addr = (void __user *) fp->un.fmt9.iaddr;
1122		break;
1123	    case 10:
1124		addr = (void __user *) fp->un.fmta.daddr;
1125		break;
1126	    case 11:
1127		addr = (void __user*) fp->un.fmtb.daddr;
1128		break;
1129	}
1130	force_sig_fault(sig, si_code, addr);
1131}
1132
1133void die_if_kernel (char *str, struct pt_regs *fp, int nr)
1134{
1135	if (!(fp->sr & PS_S))
1136		return;
1137
1138	console_verbose();
1139	pr_crit("%s: %08x\n", str, nr);
1140	show_registers(fp);
1141	add_taint(TAINT_DIE, LOCKDEP_NOW_UNRELIABLE);
1142	do_exit(SIGSEGV);
1143}
1144
1145asmlinkage void set_esp0(unsigned long ssp)
1146{
1147	current->thread.esp0 = ssp;
1148}
1149
1150/*
1151 * This function is called if an error occur while accessing
1152 * user-space from the fpsp040 code.
1153 */
1154asmlinkage void fpsp040_die(void)
1155{
1156	do_exit(SIGSEGV);
1157}
1158
1159#ifdef CONFIG_M68KFPU_EMU
1160asmlinkage void fpemu_signal(int signal, int code, void *addr)
1161{
1162	force_sig_fault(signal, code, addr);
1163}
1164#endif