Merge branch 'for-linus' of git://git.open-osd.org/linux-open-osd
[pandora-kernel.git] / arch / m68k / kernel / traps.c
index c98add3..89362f2 100644 (file)
-#ifdef CONFIG_MMU
-#include "traps_mm.c"
+/*
+ *  linux/arch/m68k/kernel/traps.c
+ *
+ *  Copyright (C) 1993, 1994 by Hamish Macdonald
+ *
+ *  68040 fixes by Michael Rausch
+ *  68040 fixes by Martin Apel
+ *  68040 fixes and writeback by Richard Zidlicky
+ *  68060 fixes by Roman Hodek
+ *  68060 fixes by Jesper Skov
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file COPYING in the main directory of this archive
+ * for more details.
+ */
+
+/*
+ * Sets up all exception vectors
+ */
+
+#include <linux/sched.h>
+#include <linux/signal.h>
+#include <linux/kernel.h>
+#include <linux/mm.h>
+#include <linux/module.h>
+#include <linux/user.h>
+#include <linux/string.h>
+#include <linux/linkage.h>
+#include <linux/init.h>
+#include <linux/ptrace.h>
+#include <linux/kallsyms.h>
+
+#include <asm/setup.h>
+#include <asm/fpu.h>
+#include <asm/system.h>
+#include <asm/uaccess.h>
+#include <asm/traps.h>
+#include <asm/pgalloc.h>
+#include <asm/machdep.h>
+#include <asm/siginfo.h>
+
+
+static const char *vec_names[] = {
+       [VEC_RESETSP]   = "RESET SP",
+       [VEC_RESETPC]   = "RESET PC",
+       [VEC_BUSERR]    = "BUS ERROR",
+       [VEC_ADDRERR]   = "ADDRESS ERROR",
+       [VEC_ILLEGAL]   = "ILLEGAL INSTRUCTION",
+       [VEC_ZERODIV]   = "ZERO DIVIDE",
+       [VEC_CHK]       = "CHK",
+       [VEC_TRAP]      = "TRAPcc",
+       [VEC_PRIV]      = "PRIVILEGE VIOLATION",
+       [VEC_TRACE]     = "TRACE",
+       [VEC_LINE10]    = "LINE 1010",
+       [VEC_LINE11]    = "LINE 1111",
+       [VEC_RESV12]    = "UNASSIGNED RESERVED 12",
+       [VEC_COPROC]    = "COPROCESSOR PROTOCOL VIOLATION",
+       [VEC_FORMAT]    = "FORMAT ERROR",
+       [VEC_UNINT]     = "UNINITIALIZED INTERRUPT",
+       [VEC_RESV16]    = "UNASSIGNED RESERVED 16",
+       [VEC_RESV17]    = "UNASSIGNED RESERVED 17",
+       [VEC_RESV18]    = "UNASSIGNED RESERVED 18",
+       [VEC_RESV19]    = "UNASSIGNED RESERVED 19",
+       [VEC_RESV20]    = "UNASSIGNED RESERVED 20",
+       [VEC_RESV21]    = "UNASSIGNED RESERVED 21",
+       [VEC_RESV22]    = "UNASSIGNED RESERVED 22",
+       [VEC_RESV23]    = "UNASSIGNED RESERVED 23",
+       [VEC_SPUR]      = "SPURIOUS INTERRUPT",
+       [VEC_INT1]      = "LEVEL 1 INT",
+       [VEC_INT2]      = "LEVEL 2 INT",
+       [VEC_INT3]      = "LEVEL 3 INT",
+       [VEC_INT4]      = "LEVEL 4 INT",
+       [VEC_INT5]      = "LEVEL 5 INT",
+       [VEC_INT6]      = "LEVEL 6 INT",
+       [VEC_INT7]      = "LEVEL 7 INT",
+       [VEC_SYS]       = "SYSCALL",
+       [VEC_TRAP1]     = "TRAP #1",
+       [VEC_TRAP2]     = "TRAP #2",
+       [VEC_TRAP3]     = "TRAP #3",
+       [VEC_TRAP4]     = "TRAP #4",
+       [VEC_TRAP5]     = "TRAP #5",
+       [VEC_TRAP6]     = "TRAP #6",
+       [VEC_TRAP7]     = "TRAP #7",
+       [VEC_TRAP8]     = "TRAP #8",
+       [VEC_TRAP9]     = "TRAP #9",
+       [VEC_TRAP10]    = "TRAP #10",
+       [VEC_TRAP11]    = "TRAP #11",
+       [VEC_TRAP12]    = "TRAP #12",
+       [VEC_TRAP13]    = "TRAP #13",
+       [VEC_TRAP14]    = "TRAP #14",
+       [VEC_TRAP15]    = "TRAP #15",
+       [VEC_FPBRUC]    = "FPCP BSUN",
+       [VEC_FPIR]      = "FPCP INEXACT",
+       [VEC_FPDIVZ]    = "FPCP DIV BY 0",
+       [VEC_FPUNDER]   = "FPCP UNDERFLOW",
+       [VEC_FPOE]      = "FPCP OPERAND ERROR",
+       [VEC_FPOVER]    = "FPCP OVERFLOW",
+       [VEC_FPNAN]     = "FPCP SNAN",
+       [VEC_FPUNSUP]   = "FPCP UNSUPPORTED OPERATION",
+       [VEC_MMUCFG]    = "MMU CONFIGURATION ERROR",
+       [VEC_MMUILL]    = "MMU ILLEGAL OPERATION ERROR",
+       [VEC_MMUACC]    = "MMU ACCESS LEVEL VIOLATION ERROR",
+       [VEC_RESV59]    = "UNASSIGNED RESERVED 59",
+       [VEC_UNIMPEA]   = "UNASSIGNED RESERVED 60",
+       [VEC_UNIMPII]   = "UNASSIGNED RESERVED 61",
+       [VEC_RESV62]    = "UNASSIGNED RESERVED 62",
+       [VEC_RESV63]    = "UNASSIGNED RESERVED 63",
+};
+
+static const char *space_names[] = {
+       [0]             = "Space 0",
+       [USER_DATA]     = "User Data",
+       [USER_PROGRAM]  = "User Program",
+#ifndef CONFIG_SUN3
+       [3]             = "Space 3",
 #else
-#include "traps_no.c"
+       [FC_CONTROL]    = "Control",
+#endif
+       [4]             = "Space 4",
+       [SUPER_DATA]    = "Super Data",
+       [SUPER_PROGRAM] = "Super Program",
+       [CPU_SPACE]     = "CPU"
+};
+
+void die_if_kernel(char *,struct pt_regs *,int);
+asmlinkage int do_page_fault(struct pt_regs *regs, unsigned long address,
+                             unsigned long error_code);
+int send_fault_sig(struct pt_regs *regs);
+
+asmlinkage void trap_c(struct frame *fp);
+
+#if defined (CONFIG_M68060)
+static inline void access_error060 (struct frame *fp)
+{
+       unsigned long fslw = fp->un.fmt4.pc; /* is really FSLW for access error */
+
+#ifdef DEBUG
+       printk("fslw=%#lx, fa=%#lx\n", fslw, fp->un.fmt4.effaddr);
+#endif
+
+       if (fslw & MMU060_BPE) {
+               /* branch prediction error -> clear branch cache */
+               __asm__ __volatile__ ("movec %/cacr,%/d0\n\t"
+                                     "orl   #0x00400000,%/d0\n\t"
+                                     "movec %/d0,%/cacr"
+                                     : : : "d0" );
+               /* return if there's no other error */
+               if (!(fslw & MMU060_ERR_BITS) && !(fslw & MMU060_SEE))
+                       return;
+       }
+
+       if (fslw & (MMU060_DESC_ERR | MMU060_WP | MMU060_SP)) {
+               unsigned long errorcode;
+               unsigned long addr = fp->un.fmt4.effaddr;
+
+               if (fslw & MMU060_MA)
+                       addr = (addr + PAGE_SIZE - 1) & PAGE_MASK;
+
+               errorcode = 1;
+               if (fslw & MMU060_DESC_ERR) {
+                       __flush_tlb040_one(addr);
+                       errorcode = 0;
+               }
+               if (fslw & MMU060_W)
+                       errorcode |= 2;
+#ifdef DEBUG
+               printk("errorcode = %d\n", errorcode );
+#endif
+               do_page_fault(&fp->ptregs, addr, errorcode);
+       } else if (fslw & (MMU060_SEE)){
+               /* Software Emulation Error.
+                * fault during mem_read/mem_write in ifpsp060/os.S
+                */
+               send_fault_sig(&fp->ptregs);
+       } else if (!(fslw & (MMU060_RE|MMU060_WE)) ||
+                  send_fault_sig(&fp->ptregs) > 0) {
+               printk("pc=%#lx, fa=%#lx\n", fp->ptregs.pc, fp->un.fmt4.effaddr);
+               printk( "68060 access error, fslw=%lx\n", fslw );
+               trap_c( fp );
+       }
+}
+#endif /* CONFIG_M68060 */
+
+#if defined (CONFIG_M68040)
+static inline unsigned long probe040(int iswrite, unsigned long addr, int wbs)
+{
+       unsigned long mmusr;
+       mm_segment_t old_fs = get_fs();
+
+       set_fs(MAKE_MM_SEG(wbs));
+
+       if (iswrite)
+               asm volatile (".chip 68040; ptestw (%0); .chip 68k" : : "a" (addr));
+       else
+               asm volatile (".chip 68040; ptestr (%0); .chip 68k" : : "a" (addr));
+
+       asm volatile (".chip 68040; movec %%mmusr,%0; .chip 68k" : "=r" (mmusr));
+
+       set_fs(old_fs);
+
+       return mmusr;
+}
+
+static inline int do_040writeback1(unsigned short wbs, unsigned long wba,
+                                  unsigned long wbd)
+{
+       int res = 0;
+       mm_segment_t old_fs = get_fs();
+
+       /* set_fs can not be moved, otherwise put_user() may oops */
+       set_fs(MAKE_MM_SEG(wbs));
+
+       switch (wbs & WBSIZ_040) {
+       case BA_SIZE_BYTE:
+               res = put_user(wbd & 0xff, (char __user *)wba);
+               break;
+       case BA_SIZE_WORD:
+               res = put_user(wbd & 0xffff, (short __user *)wba);
+               break;
+       case BA_SIZE_LONG:
+               res = put_user(wbd, (int __user *)wba);
+               break;
+       }
+
+       /* set_fs can not be moved, otherwise put_user() may oops */
+       set_fs(old_fs);
+
+
+#ifdef DEBUG
+       printk("do_040writeback1, res=%d\n",res);
+#endif
+
+       return res;
+}
+
+/* after an exception in a writeback the stack frame corresponding
+ * to that exception is discarded, set a few bits in the old frame
+ * to simulate what it should look like
+ */
+static inline void fix_xframe040(struct frame *fp, unsigned long wba, unsigned short wbs)
+{
+       fp->un.fmt7.faddr = wba;
+       fp->un.fmt7.ssw = wbs & 0xff;
+       if (wba != current->thread.faddr)
+           fp->un.fmt7.ssw |= MA_040;
+}
+
+static inline void do_040writebacks(struct frame *fp)
+{
+       int res = 0;
+#if 0
+       if (fp->un.fmt7.wb1s & WBV_040)
+               printk("access_error040: cannot handle 1st writeback. oops.\n");
+#endif
+
+       if ((fp->un.fmt7.wb2s & WBV_040) &&
+           !(fp->un.fmt7.wb2s & WBTT_040)) {
+               res = do_040writeback1(fp->un.fmt7.wb2s, fp->un.fmt7.wb2a,
+                                      fp->un.fmt7.wb2d);
+               if (res)
+                       fix_xframe040(fp, fp->un.fmt7.wb2a, fp->un.fmt7.wb2s);
+               else
+                       fp->un.fmt7.wb2s = 0;
+       }
+
+       /* do the 2nd wb only if the first one was successful (except for a kernel wb) */
+       if (fp->un.fmt7.wb3s & WBV_040 && (!res || fp->un.fmt7.wb3s & 4)) {
+               res = do_040writeback1(fp->un.fmt7.wb3s, fp->un.fmt7.wb3a,
+                                      fp->un.fmt7.wb3d);
+               if (res)
+                   {
+                       fix_xframe040(fp, fp->un.fmt7.wb3a, fp->un.fmt7.wb3s);
+
+                       fp->un.fmt7.wb2s = fp->un.fmt7.wb3s;
+                       fp->un.fmt7.wb3s &= (~WBV_040);
+                       fp->un.fmt7.wb2a = fp->un.fmt7.wb3a;
+                       fp->un.fmt7.wb2d = fp->un.fmt7.wb3d;
+                   }
+               else
+                       fp->un.fmt7.wb3s = 0;
+       }
+
+       if (res)
+               send_fault_sig(&fp->ptregs);
+}
+
+/*
+ * called from sigreturn(), must ensure userspace code didn't
+ * manipulate exception frame to circumvent protection, then complete
+ * pending writebacks
+ * we just clear TM2 to turn it into a userspace access
+ */
+asmlinkage void berr_040cleanup(struct frame *fp)
+{
+       fp->un.fmt7.wb2s &= ~4;
+       fp->un.fmt7.wb3s &= ~4;
+
+       do_040writebacks(fp);
+}
+
+static inline void access_error040(struct frame *fp)
+{
+       unsigned short ssw = fp->un.fmt7.ssw;
+       unsigned long mmusr;
+
+#ifdef DEBUG
+       printk("ssw=%#x, fa=%#lx\n", ssw, fp->un.fmt7.faddr);
+        printk("wb1s=%#x, wb2s=%#x, wb3s=%#x\n", fp->un.fmt7.wb1s,
+               fp->un.fmt7.wb2s, fp->un.fmt7.wb3s);
+       printk ("wb2a=%lx, wb3a=%lx, wb2d=%lx, wb3d=%lx\n",
+               fp->un.fmt7.wb2a, fp->un.fmt7.wb3a,
+               fp->un.fmt7.wb2d, fp->un.fmt7.wb3d);
+#endif
+
+       if (ssw & ATC_040) {
+               unsigned long addr = fp->un.fmt7.faddr;
+               unsigned long errorcode;
+
+               /*
+                * The MMU status has to be determined AFTER the address
+                * has been corrected if there was a misaligned access (MA).
+                */
+               if (ssw & MA_040)
+                       addr = (addr + 7) & -8;
+
+               /* MMU error, get the MMUSR info for this access */
+               mmusr = probe040(!(ssw & RW_040), addr, ssw);
+#ifdef DEBUG
+               printk("mmusr = %lx\n", mmusr);
+#endif
+               errorcode = 1;
+               if (!(mmusr & MMU_R_040)) {
+                       /* clear the invalid atc entry */
+                       __flush_tlb040_one(addr);
+                       errorcode = 0;
+               }
+
+               /* despite what documentation seems to say, RMW
+                * accesses have always both the LK and RW bits set */
+               if (!(ssw & RW_040) || (ssw & LK_040))
+                       errorcode |= 2;
+
+               if (do_page_fault(&fp->ptregs, addr, errorcode)) {
+#ifdef DEBUG
+                       printk("do_page_fault() !=0\n");
+#endif
+                       if (user_mode(&fp->ptregs)){
+                               /* delay writebacks after signal delivery */
+#ifdef DEBUG
+                               printk(".. was usermode - return\n");
+#endif
+                               return;
+                       }
+                       /* disable writeback into user space from kernel
+                        * (if do_page_fault didn't fix the mapping,
+                         * the writeback won't do good)
+                        */
+disable_wb:
+#ifdef DEBUG
+                       printk(".. disabling wb2\n");
+#endif
+                       if (fp->un.fmt7.wb2a == fp->un.fmt7.faddr)
+                               fp->un.fmt7.wb2s &= ~WBV_040;
+                       if (fp->un.fmt7.wb3a == fp->un.fmt7.faddr)
+                               fp->un.fmt7.wb3s &= ~WBV_040;
+               }
+       } else {
+               /* In case of a bus error we either kill the process or expect
+                * the kernel to catch the fault, which then is also responsible
+                * for cleaning up the mess.
+                */
+               current->thread.signo = SIGBUS;
+               current->thread.faddr = fp->un.fmt7.faddr;
+               if (send_fault_sig(&fp->ptregs) >= 0)
+                       printk("68040 bus error (ssw=%x, faddr=%lx)\n", ssw,
+                              fp->un.fmt7.faddr);
+               goto disable_wb;
+       }
+
+       do_040writebacks(fp);
+}
+#endif /* CONFIG_M68040 */
+
+#if defined(CONFIG_SUN3)
+#include <asm/sun3mmu.h>
+
+extern int mmu_emu_handle_fault (unsigned long, int, int);
+
+/* sun3 version of bus_error030 */
+
+static inline void bus_error030 (struct frame *fp)
+{
+       unsigned char buserr_type = sun3_get_buserr ();
+       unsigned long addr, errorcode;
+       unsigned short ssw = fp->un.fmtb.ssw;
+       extern unsigned long _sun3_map_test_start, _sun3_map_test_end;
+
+#ifdef DEBUG
+       if (ssw & (FC | FB))
+               printk ("Instruction fault at %#010lx\n",
+                       ssw & FC ?
+                       fp->ptregs.format == 0xa ? fp->ptregs.pc + 2 : fp->un.fmtb.baddr - 2
+                       :
+                       fp->ptregs.format == 0xa ? fp->ptregs.pc + 4 : fp->un.fmtb.baddr);
+       if (ssw & DF)
+               printk ("Data %s fault at %#010lx in %s (pc=%#lx)\n",
+                       ssw & RW ? "read" : "write",
+                       fp->un.fmtb.daddr,
+                       space_names[ssw & DFC], fp->ptregs.pc);
+#endif
+
+       /*
+        * Check if this page should be demand-mapped. This needs to go before
+        * the testing for a bad kernel-space access (demand-mapping applies
+        * to kernel accesses too).
+        */
+
+       if ((ssw & DF)
+           && (buserr_type & (SUN3_BUSERR_PROTERR | SUN3_BUSERR_INVALID))) {
+               if (mmu_emu_handle_fault (fp->un.fmtb.daddr, ssw & RW, 0))
+                       return;
+       }
+
+       /* Check for kernel-space pagefault (BAD). */
+       if (fp->ptregs.sr & PS_S) {
+               /* kernel fault must be a data fault to user space */
+               if (! ((ssw & DF) && ((ssw & DFC) == USER_DATA))) {
+                    // try checking the kernel mappings before surrender
+                    if (mmu_emu_handle_fault (fp->un.fmtb.daddr, ssw & RW, 1))
+                         return;
+                       /* instruction fault or kernel data fault! */
+                       if (ssw & (FC | FB))
+                               printk ("Instruction fault at %#010lx\n",
+                                       fp->ptregs.pc);
+                       if (ssw & DF) {
+                               /* was this fault incurred testing bus mappings? */
+                               if((fp->ptregs.pc >= (unsigned long)&_sun3_map_test_start) &&
+                                  (fp->ptregs.pc <= (unsigned long)&_sun3_map_test_end)) {
+                                       send_fault_sig(&fp->ptregs);
+                                       return;
+                               }
+
+                               printk ("Data %s fault at %#010lx in %s (pc=%#lx)\n",
+                                       ssw & RW ? "read" : "write",
+                                       fp->un.fmtb.daddr,
+                                       space_names[ssw & DFC], fp->ptregs.pc);
+                       }
+                       printk ("BAD KERNEL BUSERR\n");
+
+                       die_if_kernel("Oops", &fp->ptregs,0);
+                       force_sig(SIGKILL, current);
+                       return;
+               }
+       } else {
+               /* user fault */
+               if (!(ssw & (FC | FB)) && !(ssw & DF))
+                       /* not an instruction fault or data fault! BAD */
+                       panic ("USER BUSERR w/o instruction or data fault");
+       }
+
+
+       /* First handle the data fault, if any.  */
+       if (ssw & DF) {
+               addr = fp->un.fmtb.daddr;
+
+// errorcode bit 0:    0 -> no page            1 -> protection fault
+// errorcode bit 1:    0 -> read fault         1 -> write fault
+
+// (buserr_type & SUN3_BUSERR_PROTERR) -> protection fault
+// (buserr_type & SUN3_BUSERR_INVALID) -> invalid page fault
+
+               if (buserr_type & SUN3_BUSERR_PROTERR)
+                       errorcode = 0x01;
+               else if (buserr_type & SUN3_BUSERR_INVALID)
+                       errorcode = 0x00;
+               else {
+#ifdef DEBUG
+                       printk ("*** unexpected busfault type=%#04x\n", buserr_type);
+                       printk ("invalid %s access at %#lx from pc %#lx\n",
+                               !(ssw & RW) ? "write" : "read", addr,
+                               fp->ptregs.pc);
+#endif
+                       die_if_kernel ("Oops", &fp->ptregs, buserr_type);
+                       force_sig (SIGBUS, current);
+                       return;
+               }
+
+//todo: wtf is RM bit? --m
+               if (!(ssw & RW) || ssw & RM)
+                       errorcode |= 0x02;
+
+               /* Handle page fault. */
+               do_page_fault (&fp->ptregs, addr, errorcode);
+
+               /* Retry the data fault now. */
+               return;
+       }
+
+       /* Now handle the instruction fault. */
+
+       /* Get the fault address. */
+       if (fp->ptregs.format == 0xA)
+               addr = fp->ptregs.pc + 4;
+       else
+               addr = fp->un.fmtb.baddr;
+       if (ssw & FC)
+               addr -= 2;
+
+       if (buserr_type & SUN3_BUSERR_INVALID) {
+               if (!mmu_emu_handle_fault (fp->un.fmtb.daddr, 1, 0))
+                       do_page_fault (&fp->ptregs, addr, 0);
+       } else {
+#ifdef DEBUG
+               printk ("protection fault on insn access (segv).\n");
+#endif
+               force_sig (SIGSEGV, current);
+       }
+}
+#else
+#if defined(CPU_M68020_OR_M68030)
+static inline void bus_error030 (struct frame *fp)
+{
+       volatile unsigned short temp;
+       unsigned short mmusr;
+       unsigned long addr, errorcode;
+       unsigned short ssw = fp->un.fmtb.ssw;
+#ifdef DEBUG
+       unsigned long desc;
+
+       printk ("pid = %x  ", current->pid);
+       printk ("SSW=%#06x  ", ssw);
+
+       if (ssw & (FC | FB))
+               printk ("Instruction fault at %#010lx\n",
+                       ssw & FC ?
+                       fp->ptregs.format == 0xa ? fp->ptregs.pc + 2 : fp->un.fmtb.baddr - 2
+                       :
+                       fp->ptregs.format == 0xa ? fp->ptregs.pc + 4 : fp->un.fmtb.baddr);
+       if (ssw & DF)
+               printk ("Data %s fault at %#010lx in %s (pc=%#lx)\n",
+                       ssw & RW ? "read" : "write",
+                       fp->un.fmtb.daddr,
+                       space_names[ssw & DFC], fp->ptregs.pc);
+#endif
+
+       /* ++andreas: If a data fault and an instruction fault happen
+          at the same time map in both pages.  */
+
+       /* First handle the data fault, if any.  */
+       if (ssw & DF) {
+               addr = fp->un.fmtb.daddr;
+
+#ifdef DEBUG
+               asm volatile ("ptestr %3,%2@,#7,%0\n\t"
+                             "pmove %%psr,%1@"
+                             : "=a&" (desc)
+                             : "a" (&temp), "a" (addr), "d" (ssw));
+#else
+               asm volatile ("ptestr %2,%1@,#7\n\t"
+                             "pmove %%psr,%0@"
+                             : : "a" (&temp), "a" (addr), "d" (ssw));
+#endif
+               mmusr = temp;
+
+#ifdef DEBUG
+               printk("mmusr is %#x for addr %#lx in task %p\n",
+                      mmusr, addr, current);
+               printk("descriptor address is %#lx, contents %#lx\n",
+                      __va(desc), *(unsigned long *)__va(desc));
+#endif
+
+               errorcode = (mmusr & MMU_I) ? 0 : 1;
+               if (!(ssw & RW) || (ssw & RM))
+                       errorcode |= 2;
+
+               if (mmusr & (MMU_I | MMU_WP)) {
+                       if (ssw & 4) {
+                               printk("Data %s fault at %#010lx in %s (pc=%#lx)\n",
+                                      ssw & RW ? "read" : "write",
+                                      fp->un.fmtb.daddr,
+                                      space_names[ssw & DFC], fp->ptregs.pc);
+                               goto buserr;
+                       }
+                       /* Don't try to do anything further if an exception was
+                          handled. */
+                       if (do_page_fault (&fp->ptregs, addr, errorcode) < 0)
+                               return;
+               } else if (!(mmusr & MMU_I)) {
+                       /* probably a 020 cas fault */
+                       if (!(ssw & RM) && send_fault_sig(&fp->ptregs) > 0)
+                               printk("unexpected bus error (%#x,%#x)\n", ssw, mmusr);
+               } else if (mmusr & (MMU_B|MMU_L|MMU_S)) {
+                       printk("invalid %s access at %#lx from pc %#lx\n",
+                              !(ssw & RW) ? "write" : "read", addr,
+                              fp->ptregs.pc);
+                       die_if_kernel("Oops",&fp->ptregs,mmusr);
+                       force_sig(SIGSEGV, current);
+                       return;
+               } else {
+#if 0
+                       static volatile long tlong;
+#endif
+
+                       printk("weird %s access at %#lx from pc %#lx (ssw is %#x)\n",
+                              !(ssw & RW) ? "write" : "read", addr,
+                              fp->ptregs.pc, ssw);
+                       asm volatile ("ptestr #1,%1@,#0\n\t"
+                                     "pmove %%psr,%0@"
+                                     : /* no outputs */
+                                     : "a" (&temp), "a" (addr));
+                       mmusr = temp;
+
+                       printk ("level 0 mmusr is %#x\n", mmusr);
+#if 0
+                       asm volatile ("pmove %%tt0,%0@"
+                                     : /* no outputs */
+                                     : "a" (&tlong));
+                       printk("tt0 is %#lx, ", tlong);
+                       asm volatile ("pmove %%tt1,%0@"
+                                     : /* no outputs */
+                                     : "a" (&tlong));
+                       printk("tt1 is %#lx\n", tlong);
+#endif
+#ifdef DEBUG
+                       printk("Unknown SIGSEGV - 1\n");
+#endif
+                       die_if_kernel("Oops",&fp->ptregs,mmusr);
+                       force_sig(SIGSEGV, current);
+                       return;
+               }
+
+               /* setup an ATC entry for the access about to be retried */
+               if (!(ssw & RW) || (ssw & RM))
+                       asm volatile ("ploadw %1,%0@" : /* no outputs */
+                                     : "a" (addr), "d" (ssw));
+               else
+                       asm volatile ("ploadr %1,%0@" : /* no outputs */
+                                     : "a" (addr), "d" (ssw));
+       }
+
+       /* Now handle the instruction fault. */
+
+       if (!(ssw & (FC|FB)))
+               return;
+
+       if (fp->ptregs.sr & PS_S) {
+               printk("Instruction fault at %#010lx\n",
+                       fp->ptregs.pc);
+       buserr:
+               printk ("BAD KERNEL BUSERR\n");
+               die_if_kernel("Oops",&fp->ptregs,0);
+               force_sig(SIGKILL, current);
+               return;
+       }
+
+       /* get the fault address */
+       if (fp->ptregs.format == 10)
+               addr = fp->ptregs.pc + 4;
+       else
+               addr = fp->un.fmtb.baddr;
+       if (ssw & FC)
+               addr -= 2;
+
+       if ((ssw & DF) && ((addr ^ fp->un.fmtb.daddr) & PAGE_MASK) == 0)
+               /* Insn fault on same page as data fault.  But we
+                  should still create the ATC entry.  */
+               goto create_atc_entry;
+
+#ifdef DEBUG
+       asm volatile ("ptestr #1,%2@,#7,%0\n\t"
+                     "pmove %%psr,%1@"
+                     : "=a&" (desc)
+                     : "a" (&temp), "a" (addr));
+#else
+       asm volatile ("ptestr #1,%1@,#7\n\t"
+                     "pmove %%psr,%0@"
+                     : : "a" (&temp), "a" (addr));
+#endif
+       mmusr = temp;
+
+#ifdef DEBUG
+       printk ("mmusr is %#x for addr %#lx in task %p\n",
+               mmusr, addr, current);
+       printk ("descriptor address is %#lx, contents %#lx\n",
+               __va(desc), *(unsigned long *)__va(desc));
+#endif
+
+       if (mmusr & MMU_I)
+               do_page_fault (&fp->ptregs, addr, 0);
+       else if (mmusr & (MMU_B|MMU_L|MMU_S)) {
+               printk ("invalid insn access at %#lx from pc %#lx\n",
+                       addr, fp->ptregs.pc);
+#ifdef DEBUG
+               printk("Unknown SIGSEGV - 2\n");
+#endif
+               die_if_kernel("Oops",&fp->ptregs,mmusr);
+               force_sig(SIGSEGV, current);
+               return;
+       }
+
+create_atc_entry:
+       /* setup an ATC entry for the access about to be retried */
+       asm volatile ("ploadr #2,%0@" : /* no outputs */
+                     : "a" (addr));
+}
+#endif /* CPU_M68020_OR_M68030 */
+#endif /* !CONFIG_SUN3 */
+
+asmlinkage void buserr_c(struct frame *fp)
+{
+       /* Only set esp0 if coming from user mode */
+       if (user_mode(&fp->ptregs))
+               current->thread.esp0 = (unsigned long) fp;
+
+#ifdef DEBUG
+       printk ("*** Bus Error *** Format is %x\n", fp->ptregs.format);
+#endif
+
+       switch (fp->ptregs.format) {
+#if defined (CONFIG_M68060)
+       case 4:                         /* 68060 access error */
+         access_error060 (fp);
+         break;
+#endif
+#if defined (CONFIG_M68040)
+       case 0x7:                       /* 68040 access error */
+         access_error040 (fp);
+         break;
+#endif
+#if defined (CPU_M68020_OR_M68030)
+       case 0xa:
+       case 0xb:
+         bus_error030 (fp);
+         break;
+#endif
+       default:
+         die_if_kernel("bad frame format",&fp->ptregs,0);
+#ifdef DEBUG
+         printk("Unknown SIGSEGV - 4\n");
+#endif
+         force_sig(SIGSEGV, current);
+       }
+}
+
+
+static int kstack_depth_to_print = 48;
+
+void show_trace(unsigned long *stack)
+{
+       unsigned long *endstack;
+       unsigned long addr;
+       int i;
+
+       printk("Call Trace:");
+       addr = (unsigned long)stack + THREAD_SIZE - 1;
+       endstack = (unsigned long *)(addr & -THREAD_SIZE);
+       i = 0;
+       while (stack + 1 <= endstack) {
+               addr = *stack++;
+               /*
+                * If the address is either in the text segment of the
+                * kernel, or in the region which contains vmalloc'ed
+                * memory, it *may* be the address of a calling
+                * routine; if so, print it so that someone tracing
+                * down the cause of the crash will be able to figure
+                * out the call path that was taken.
+                */
+               if (__kernel_text_address(addr)) {
+#ifndef CONFIG_KALLSYMS
+                       if (i % 5 == 0)
+                               printk("\n       ");
+#endif
+                       printk(" [<%08lx>] %pS\n", addr, (void *)addr);
+                       i++;
+               }
+       }
+       printk("\n");
+}
+
+void show_registers(struct pt_regs *regs)
+{
+       struct frame *fp = (struct frame *)regs;
+       mm_segment_t old_fs = get_fs();
+       u16 c, *cp;
+       unsigned long addr;
+       int i;
+
+       print_modules();
+       printk("PC: [<%08lx>] %pS\n", regs->pc, (void *)regs->pc);
+       printk("SR: %04x  SP: %p  a2: %08lx\n", regs->sr, regs, regs->a2);
+       printk("d0: %08lx    d1: %08lx    d2: %08lx    d3: %08lx\n",
+              regs->d0, regs->d1, regs->d2, regs->d3);
+       printk("d4: %08lx    d5: %08lx    a0: %08lx    a1: %08lx\n",
+              regs->d4, regs->d5, regs->a0, regs->a1);
+
+       printk("Process %s (pid: %d, task=%p)\n",
+               current->comm, task_pid_nr(current), current);
+       addr = (unsigned long)&fp->un;
+       printk("Frame format=%X ", regs->format);
+       switch (regs->format) {
+       case 0x2:
+               printk("instr addr=%08lx\n", fp->un.fmt2.iaddr);
+               addr += sizeof(fp->un.fmt2);
+               break;
+       case 0x3:
+               printk("eff addr=%08lx\n", fp->un.fmt3.effaddr);
+               addr += sizeof(fp->un.fmt3);
+               break;
+       case 0x4:
+               printk((CPU_IS_060 ? "fault addr=%08lx fslw=%08lx\n"
+                       : "eff addr=%08lx pc=%08lx\n"),
+                       fp->un.fmt4.effaddr, fp->un.fmt4.pc);
+               addr += sizeof(fp->un.fmt4);
+               break;
+       case 0x7:
+               printk("eff addr=%08lx ssw=%04x faddr=%08lx\n",
+                       fp->un.fmt7.effaddr, fp->un.fmt7.ssw, fp->un.fmt7.faddr);
+               printk("wb 1 stat/addr/data: %04x %08lx %08lx\n",
+                       fp->un.fmt7.wb1s, fp->un.fmt7.wb1a, fp->un.fmt7.wb1dpd0);
+               printk("wb 2 stat/addr/data: %04x %08lx %08lx\n",
+                       fp->un.fmt7.wb2s, fp->un.fmt7.wb2a, fp->un.fmt7.wb2d);
+               printk("wb 3 stat/addr/data: %04x %08lx %08lx\n",
+                       fp->un.fmt7.wb3s, fp->un.fmt7.wb3a, fp->un.fmt7.wb3d);
+               printk("push data: %08lx %08lx %08lx %08lx\n",
+                       fp->un.fmt7.wb1dpd0, fp->un.fmt7.pd1, fp->un.fmt7.pd2,
+                       fp->un.fmt7.pd3);
+               addr += sizeof(fp->un.fmt7);
+               break;
+       case 0x9:
+               printk("instr addr=%08lx\n", fp->un.fmt9.iaddr);
+               addr += sizeof(fp->un.fmt9);
+               break;
+       case 0xa:
+               printk("ssw=%04x isc=%04x isb=%04x daddr=%08lx dobuf=%08lx\n",
+                       fp->un.fmta.ssw, fp->un.fmta.isc, fp->un.fmta.isb,
+                       fp->un.fmta.daddr, fp->un.fmta.dobuf);
+               addr += sizeof(fp->un.fmta);
+               break;
+       case 0xb:
+               printk("ssw=%04x isc=%04x isb=%04x daddr=%08lx dobuf=%08lx\n",
+                       fp->un.fmtb.ssw, fp->un.fmtb.isc, fp->un.fmtb.isb,
+                       fp->un.fmtb.daddr, fp->un.fmtb.dobuf);
+               printk("baddr=%08lx dibuf=%08lx ver=%x\n",
+                       fp->un.fmtb.baddr, fp->un.fmtb.dibuf, fp->un.fmtb.ver);
+               addr += sizeof(fp->un.fmtb);
+               break;
+       default:
+               printk("\n");
+       }
+       show_stack(NULL, (unsigned long *)addr);
+
+       printk("Code:");
+       set_fs(KERNEL_DS);
+       cp = (u16 *)regs->pc;
+       for (i = -8; i < 16; i++) {
+               if (get_user(c, cp + i) && i >= 0) {
+                       printk(" Bad PC value.");
+                       break;
+               }
+               printk(i ? " %04x" : " <%04x>", c);
+       }
+       set_fs(old_fs);
+       printk ("\n");
+}
+
+void show_stack(struct task_struct *task, unsigned long *stack)
+{
+       unsigned long *p;
+       unsigned long *endstack;
+       int i;
+
+       if (!stack) {
+               if (task)
+                       stack = (unsigned long *)task->thread.esp0;
+               else
+                       stack = (unsigned long *)&stack;
+       }
+       endstack = (unsigned long *)(((unsigned long)stack + THREAD_SIZE - 1) & -THREAD_SIZE);
+
+       printk("Stack from %08lx:", (unsigned long)stack);
+       p = stack;
+       for (i = 0; i < kstack_depth_to_print; i++) {
+               if (p + 1 > endstack)
+                       break;
+               if (i % 8 == 0)
+                       printk("\n       ");
+               printk(" %08lx", *p++);
+       }
+       printk("\n");
+       show_trace(stack);
+}
+
+/*
+ * The architecture-independent backtrace generator
+ */
+void dump_stack(void)
+{
+       unsigned long stack;
+
+       show_trace(&stack);
+}
+
+EXPORT_SYMBOL(dump_stack);
+
+/*
+ * The vector number returned in the frame pointer may also contain
+ * the "fs" (Fault Status) bits on ColdFire. These are in the bottom
+ * 2 bits, and upper 2 bits. So we need to mask out the real vector
+ * number before using it in comparisons. You don't need to do this on
+ * real 68k parts, but it won't hurt either.
+ */
+
+void bad_super_trap (struct frame *fp)
+{
+       int vector = (fp->ptregs.vector >> 2) & 0xff;
+
+       console_verbose();
+       if (vector < ARRAY_SIZE(vec_names))
+               printk ("*** %s ***   FORMAT=%X\n",
+                       vec_names[vector],
+                       fp->ptregs.format);
+       else
+               printk ("*** Exception %d ***   FORMAT=%X\n",
+                       vector, fp->ptregs.format);
+       if (vector == VEC_ADDRERR && CPU_IS_020_OR_030) {
+               unsigned short ssw = fp->un.fmtb.ssw;
+
+               printk ("SSW=%#06x  ", ssw);
+
+               if (ssw & RC)
+                       printk ("Pipe stage C instruction fault at %#010lx\n",
+                               (fp->ptregs.format) == 0xA ?
+                               fp->ptregs.pc + 2 : fp->un.fmtb.baddr - 2);
+               if (ssw & RB)
+                       printk ("Pipe stage B instruction fault at %#010lx\n",
+                               (fp->ptregs.format) == 0xA ?
+                               fp->ptregs.pc + 4 : fp->un.fmtb.baddr);
+               if (ssw & DF)
+                       printk ("Data %s fault at %#010lx in %s (pc=%#lx)\n",
+                               ssw & RW ? "read" : "write",
+                               fp->un.fmtb.daddr, space_names[ssw & DFC],
+                               fp->ptregs.pc);
+       }
+       printk ("Current process id is %d\n", task_pid_nr(current));
+       die_if_kernel("BAD KERNEL TRAP", &fp->ptregs, 0);
+}
+
+asmlinkage void trap_c(struct frame *fp)
+{
+       int sig;
+       int vector = (fp->ptregs.vector >> 2) & 0xff;
+       siginfo_t info;
+
+       if (fp->ptregs.sr & PS_S) {
+               if (vector == VEC_TRACE) {
+                       /* traced a trapping instruction on a 68020/30,
+                        * real exception will be executed afterwards.
+                        */
+               } else if (!handle_kernel_fault(&fp->ptregs))
+                       bad_super_trap(fp);
+               return;
+       }
+
+       /* send the appropriate signal to the user program */
+       switch (vector) {
+           case VEC_ADDRERR:
+               info.si_code = BUS_ADRALN;
+               sig = SIGBUS;
+               break;
+           case VEC_ILLEGAL:
+           case VEC_LINE10:
+           case VEC_LINE11:
+               info.si_code = ILL_ILLOPC;
+               sig = SIGILL;
+               break;
+           case VEC_PRIV:
+               info.si_code = ILL_PRVOPC;
+               sig = SIGILL;
+               break;
+           case VEC_COPROC:
+               info.si_code = ILL_COPROC;
+               sig = SIGILL;
+               break;
+           case VEC_TRAP1:
+           case VEC_TRAP2:
+           case VEC_TRAP3:
+           case VEC_TRAP4:
+           case VEC_TRAP5:
+           case VEC_TRAP6:
+           case VEC_TRAP7:
+           case VEC_TRAP8:
+           case VEC_TRAP9:
+           case VEC_TRAP10:
+           case VEC_TRAP11:
+           case VEC_TRAP12:
+           case VEC_TRAP13:
+           case VEC_TRAP14:
+               info.si_code = ILL_ILLTRP;
+               sig = SIGILL;
+               break;
+           case VEC_FPBRUC:
+           case VEC_FPOE:
+           case VEC_FPNAN:
+               info.si_code = FPE_FLTINV;
+               sig = SIGFPE;
+               break;
+           case VEC_FPIR:
+               info.si_code = FPE_FLTRES;
+               sig = SIGFPE;
+               break;
+           case VEC_FPDIVZ:
+               info.si_code = FPE_FLTDIV;
+               sig = SIGFPE;
+               break;
+           case VEC_FPUNDER:
+               info.si_code = FPE_FLTUND;
+               sig = SIGFPE;
+               break;
+           case VEC_FPOVER:
+               info.si_code = FPE_FLTOVF;
+               sig = SIGFPE;
+               break;
+           case VEC_ZERODIV:
+               info.si_code = FPE_INTDIV;
+               sig = SIGFPE;
+               break;
+           case VEC_CHK:
+           case VEC_TRAP:
+               info.si_code = FPE_INTOVF;
+               sig = SIGFPE;
+               break;
+           case VEC_TRACE:             /* ptrace single step */
+               info.si_code = TRAP_TRACE;
+               sig = SIGTRAP;
+               break;
+           case VEC_TRAP15:            /* breakpoint */
+               info.si_code = TRAP_BRKPT;
+               sig = SIGTRAP;
+               break;
+           default:
+               info.si_code = ILL_ILLOPC;
+               sig = SIGILL;
+               break;
+       }
+       info.si_signo = sig;
+       info.si_errno = 0;
+       switch (fp->ptregs.format) {
+           default:
+               info.si_addr = (void *) fp->ptregs.pc;
+               break;
+           case 2:
+               info.si_addr = (void *) fp->un.fmt2.iaddr;
+               break;
+           case 7:
+               info.si_addr = (void *) fp->un.fmt7.effaddr;
+               break;
+           case 9:
+               info.si_addr = (void *) fp->un.fmt9.iaddr;
+               break;
+           case 10:
+               info.si_addr = (void *) fp->un.fmta.daddr;
+               break;
+           case 11:
+               info.si_addr = (void *) fp->un.fmtb.daddr;
+               break;
+       }
+       force_sig_info (sig, &info, current);
+}
+
+void die_if_kernel (char *str, struct pt_regs *fp, int nr)
+{
+       if (!(fp->sr & PS_S))
+               return;
+
+       console_verbose();
+       printk("%s: %08x\n",str,nr);
+       show_registers(fp);
+       add_taint(TAINT_DIE);
+       do_exit(SIGSEGV);
+}
+
+asmlinkage void set_esp0(unsigned long ssp)
+{
+       current->thread.esp0 = ssp;
+}
+
+/*
+ * This function is called if an error occur while accessing
+ * user-space from the fpsp040 code.
+ */
+asmlinkage void fpsp040_die(void)
+{
+       do_exit(SIGSEGV);
+}
+
+#ifdef CONFIG_M68KFPU_EMU
+asmlinkage void fpemu_signal(int signal, int code, void *addr)
+{
+       siginfo_t info;
+
+       info.si_signo = signal;
+       info.si_errno = 0;
+       info.si_code = code;
+       info.si_addr = addr;
+       force_sig_info(signal, &info, current);
+}
 #endif