arch/m32r/kernel/traps.c

   1 /*
   2  *  linux/arch/m32r/kernel/traps.c
   3  *
   4  *  Copyright (C) 2001, 2002  Hirokazu Takata, Hiroyuki Kondo,
   5  *                            Hitoshi Yamamoto
   6  */
   7
   8 /*
   9  * 'traps.c' handles hardware traps and faults after we have saved some
  10  * state in 'entry.S'.
  11  */
  12 #include <linux/init.h>
  13 #include <linux/kernel.h>
  14 #include <linux/kallsyms.h>
  15 #include <linux/stddef.h>
  16 #include <linux/ptrace.h>
  17 #include <linux/sched/debug.h>
  18 #include <linux/sched/task_stack.h>
  19 #include <linux/mm.h>
  20
  21 #include <asm/page.h>
  22 #include <asm/processor.h>
  23
  24 #include <linux/uaccess.h>
  25 #include <asm/io.h>
  26 #include <linux/atomic.h>
  27
  28 #include <asm/smp.h>
  29
  30 #include <linux/module.h>
  31
  32 asmlinkage void alignment_check(void);
  33 asmlinkage void ei_handler(void);
  34 asmlinkage void rie_handler(void);
  35 asmlinkage void debug_trap(void);
  36 asmlinkage void cache_flushing_handler(void);
  37 asmlinkage void ill_trap(void);
  38
  39 #ifdef CONFIG_SMP
  40 extern void smp_reschedule_interrupt(void);
  41 extern void smp_invalidate_interrupt(void);
  42 extern void smp_call_function_interrupt(void);
  43 extern void smp_ipi_timer_interrupt(void);
  44 extern void smp_flush_cache_all_interrupt(void);
  45 extern void smp_call_function_single_interrupt(void);
  46
  47 /*
  48  * for Boot AP function
  49  */
  50 asm (
  51         "       .section .eit_vector4,\"ax\"    \n"
  52         "       .global _AP_RE                  \n"
  53         "       .global startup_AP              \n"
  54         "_AP_RE:                                \n"
  55         "       .fill 32, 4, 0                  \n"
  56         "_AP_EI: bra    startup_AP              \n"
  57         "       .previous                       \n"
  58 );
  59 #endif  /* CONFIG_SMP */
  60
  61 extern unsigned long    eit_vector[];
  62 #define BRA_INSN(func, entry)   \
  63         ((unsigned long)func - (unsigned long)eit_vector - entry*4)/4 \
  64         + 0xff000000UL
  65
  66 static void set_eit_vector_entries(void)
  67 {
  68         extern void default_eit_handler(void);
  69         extern void system_call(void);
  70         extern void pie_handler(void);
  71         extern void ace_handler(void);
  72         extern void tme_handler(void);
  73         extern void _flush_cache_copyback_all(void);
  74
  75         eit_vector[0] = 0xd0c00001; /* seth r0, 0x01 */
  76         eit_vector[1] = BRA_INSN(default_eit_handler, 1);
  77         eit_vector[4] = 0xd0c00010; /* seth r0, 0x10 */
  78         eit_vector[5] = BRA_INSN(default_eit_handler, 5);
  79         eit_vector[8] = BRA_INSN(rie_handler, 8);
  80         eit_vector[12] = BRA_INSN(alignment_check, 12);
  81         eit_vector[16] = BRA_INSN(ill_trap, 16);
  82         eit_vector[17] = BRA_INSN(debug_trap, 17);
  83         eit_vector[18] = BRA_INSN(system_call, 18);
  84         eit_vector[19] = BRA_INSN(ill_trap, 19);
  85         eit_vector[20] = BRA_INSN(ill_trap, 20);
  86         eit_vector[21] = BRA_INSN(ill_trap, 21);
  87         eit_vector[22] = BRA_INSN(ill_trap, 22);
  88         eit_vector[23] = BRA_INSN(ill_trap, 23);
  89         eit_vector[24] = BRA_INSN(ill_trap, 24);
  90         eit_vector[25] = BRA_INSN(ill_trap, 25);
  91         eit_vector[26] = BRA_INSN(ill_trap, 26);
  92         eit_vector[27] = BRA_INSN(ill_trap, 27);
  93         eit_vector[28] = BRA_INSN(cache_flushing_handler, 28);
  94         eit_vector[29] = BRA_INSN(ill_trap, 29);
  95         eit_vector[30] = BRA_INSN(ill_trap, 30);
  96         eit_vector[31] = BRA_INSN(ill_trap, 31);
  97         eit_vector[32] = BRA_INSN(ei_handler, 32);
  98         eit_vector[64] = BRA_INSN(pie_handler, 64);
  99 #ifdef CONFIG_MMU
 100         eit_vector[68] = BRA_INSN(ace_handler, 68);
 101         eit_vector[72] = BRA_INSN(tme_handler, 72);
 102 #endif /* CONFIG_MMU */
 103 #ifdef CONFIG_SMP
 104         eit_vector[184] = (unsigned long)smp_reschedule_interrupt;
 105         eit_vector[185] = (unsigned long)smp_invalidate_interrupt;
 106         eit_vector[186] = (unsigned long)smp_call_function_interrupt;
 107         eit_vector[187] = (unsigned long)smp_ipi_timer_interrupt;
 108         eit_vector[188] = (unsigned long)smp_flush_cache_all_interrupt;
 109         eit_vector[189] = 0;    /* CPU_BOOT_IPI */
 110         eit_vector[190] = (unsigned long)smp_call_function_single_interrupt;
 111         eit_vector[191] = 0;
 112 #endif
 113         _flush_cache_copyback_all();
 114 }
 115
 116 void __init trap_init(void)
 117 {
 118         set_eit_vector_entries();
 119
 120         /*
 121          * Should be a barrier for any external CPU state.
 122          */
 123         cpu_init();
 124 }
 125
 126 static int kstack_depth_to_print = 24;
 127
 128 static void show_trace(struct task_struct *task, unsigned long *stack)
 129 {
 130         unsigned long addr;
 131
 132         if (!stack)
 133                 stack = (unsigned long*)&stack;
 134
 135         printk("Call Trace: ");
 136         while (!kstack_end(stack)) {
 137                 addr = *stack++;
 138                 if (__kernel_text_address(addr))
 139                         printk("[<%08lx>] %pSR\n", addr, (void *)addr);
 140         }
 141         printk("\n");
 142 }
 143
 144 void show_stack(struct task_struct *task, unsigned long *sp)
 145 {
 146         unsigned long  *stack;
 147         int  i;
 148
 149         /*
 150          * debugging aid: "show_stack(NULL);" prints the
 151          * back trace for this cpu.
 152          */
 153
 154         if(sp==NULL) {
 155                 if (task)
 156                         sp = (unsigned long *)task->thread.sp;
 157                 else
 158                         sp=(unsigned long*)&sp;
 159         }
 160
 161         stack = sp;
 162         for(i=0; i < kstack_depth_to_print; i++) {
 163                 if (kstack_end(stack))
 164                         break;
 165                 if (i && ((i % 4) == 0))
 166                         printk("\n       ");
 167                 printk("%08lx ", *stack++);
 168         }
 169         printk("\n");
 170         show_trace(task, sp);
 171 }
 172
 173 static void show_registers(struct pt_regs *regs)
 174 {
 175         int i = 0;
 176         int in_kernel = 1;
 177         unsigned long sp;
 178
 179         printk("CPU:    %d\n", smp_processor_id());
 180         show_regs(regs);
 181
 182         sp = (unsigned long) (1+regs);
 183         if (user_mode(regs)) {
 184                 in_kernel = 0;
 185                 sp = regs->spu;
 186                 printk("SPU: %08lx\n", sp);
 187         } else {
 188                 printk("SPI: %08lx\n", sp);
 189         }
 190         printk("Process %s (pid: %d, process nr: %d, stackpage=%08lx)",
 191                 current->comm, task_pid_nr(current), 0xffff & i, 4096+(unsigned long)current);
 192
 193         /*
 194          * When in-kernel, we also print out the stack and code at the
 195          * time of the fault..
 196          */
 197         if (in_kernel) {
 198                 printk("\nStack: ");
 199                 show_stack(current, (unsigned long*) sp);
 200
 201                 printk("\nCode: ");
 202                 if (regs->bpc < PAGE_OFFSET)
 203                         goto bad;
 204
 205                 for(i=0;i<20;i++) {
 206                         unsigned char c;
 207                         if (__get_user(c, &((unsigned char*)regs->bpc)[i])) {
 208 bad:
 209                                 printk(" Bad PC value.");
 210                                 break;
 211                         }
 212                         printk("%02x ", c);
 213                 }
 214         }
 215         printk("\n");
 216 }
 217
 218 static DEFINE_SPINLOCK(die_lock);
 219
 220 void die(const char * str, struct pt_regs * regs, long err)
 221 {
 222         console_verbose();
 223         spin_lock_irq(&die_lock);
 224         bust_spinlocks(1);
 225         printk("%s: %04lx\n", str, err & 0xffff);
 226         show_registers(regs);
 227         bust_spinlocks(0);
 228         spin_unlock_irq(&die_lock);
 229         do_exit(SIGSEGV);
 230 }
 231
 232 static __inline__ void die_if_kernel(const char * str,
 233         struct pt_regs * regs, long err)
 234 {
 235         if (!user_mode(regs))
 236                 die(str, regs, err);
 237 }
 238
 239 static __inline__ void do_trap(int trapnr, int signr, const char * str,
 240         struct pt_regs * regs, long error_code, siginfo_t *info)
 241 {
 242         if (user_mode(regs)) {
 243                 /* trap_signal */
 244                 struct task_struct *tsk = current;
 245                 tsk->thread.error_code = error_code;
 246                 tsk->thread.trap_no = trapnr;
 247                 if (info)
 248                         force_sig_info(signr, info, tsk);
 249                 else
 250                         force_sig(signr, tsk);
 251                 return;
 252         } else {
 253                 /* kernel_trap */
 254                 if (!fixup_exception(regs))
 255                         die(str, regs, error_code);
 256                 return;
 257         }
 258 }
 259
 260 #define DO_ERROR(trapnr, signr, str, name) \
 261 asmlinkage void do_##name(struct pt_regs * regs, long error_code) \
 262 { \
 263         do_trap(trapnr, signr, NULL, regs, error_code, NULL); \
 264 }
 265
 266 #define DO_ERROR_INFO(trapnr, signr, str, name, sicode, siaddr) \
 267 asmlinkage void do_##name(struct pt_regs * regs, long error_code) \
 268 { \
 269         siginfo_t info; \
 270         info.si_signo = signr; \
 271         info.si_errno = 0; \
 272         info.si_code = sicode; \
 273         info.si_addr = (void __user *)siaddr; \
 274         do_trap(trapnr, signr, str, regs, error_code, &info); \
 275 }
 276
 277 DO_ERROR( 1, SIGTRAP, "debug trap", debug_trap)
 278 DO_ERROR_INFO(0x20, SIGILL,  "reserved instruction ", rie_handler, ILL_ILLOPC, regs->bpc)
 279 DO_ERROR_INFO(0x100, SIGILL,  "privileged instruction", pie_handler, ILL_PRVOPC, regs->bpc)
 280 DO_ERROR_INFO(-1, SIGILL,  "illegal trap", ill_trap, ILL_ILLTRP, regs->bpc)
 281
 282 extern int handle_unaligned_access(unsigned long, struct pt_regs *);
 283
 284 /* This code taken from arch/sh/kernel/traps.c */
 285 asmlinkage void do_alignment_check(struct pt_regs *regs, long error_code)
 286 {
 287         mm_segment_t oldfs;
 288         unsigned long insn;
 289         int tmp;
 290
 291         oldfs = get_fs();
 292
 293         if (user_mode(regs)) {
 294                 local_irq_enable();
 295                 current->thread.error_code = error_code;
 296                 current->thread.trap_no = 0x17;
 297
 298                 set_fs(USER_DS);
 299                 if (copy_from_user(&insn, (void *)regs->bpc, 4)) {
 300                         set_fs(oldfs);
 301                         goto uspace_segv;
 302                 }
 303                 tmp = handle_unaligned_access(insn, regs);
 304                 set_fs(oldfs);
 305
 306                 if (!tmp)
 307                         return;
 308
 309         uspace_segv:
 310                 printk(KERN_NOTICE "Killing process \"%s\" due to unaligned "
 311                         "access\n", current->comm);
 312                 force_sig(SIGSEGV, current);
 313         } else {
 314                 set_fs(KERNEL_DS);
 315                 if (copy_from_user(&insn, (void *)regs->bpc, 4)) {
 316                         set_fs(oldfs);
 317                         die("insn faulting in do_address_error", regs, 0);
 318                 }
 319                 handle_unaligned_access(insn, regs);
 320                 set_fs(oldfs);
 321         }
 322 }