~ [ source navigation ] ~ [ diff markup ] ~ [ identifier search ] ~

TOMOYO Linux Cross Reference
Linux/arch/parisc/kernel/traps.c

Version: ~ [ linux-5.6-rc1 ] ~ [ linux-5.5.2 ] ~ [ linux-5.4.17 ] ~ [ linux-5.3.18 ] ~ [ linux-5.2.21 ] ~ [ linux-5.1.21 ] ~ [ linux-5.0.21 ] ~ [ linux-4.20.17 ] ~ [ linux-4.19.102 ] ~ [ linux-4.18.20 ] ~ [ linux-4.17.19 ] ~ [ linux-4.16.18 ] ~ [ linux-4.15.18 ] ~ [ linux-4.14.170 ] ~ [ linux-4.13.16 ] ~ [ linux-4.12.14 ] ~ [ linux-4.11.12 ] ~ [ linux-4.10.17 ] ~ [ linux-4.9.213 ] ~ [ linux-4.8.17 ] ~ [ linux-4.7.10 ] ~ [ linux-4.6.7 ] ~ [ linux-4.5.7 ] ~ [ linux-4.4.213 ] ~ [ linux-4.3.6 ] ~ [ linux-4.2.8 ] ~ [ linux-4.1.52 ] ~ [ linux-4.0.9 ] ~ [ linux-3.19.8 ] ~ [ linux-3.18.140 ] ~ [ linux-3.17.8 ] ~ [ linux-3.16.81 ] ~ [ linux-3.15.10 ] ~ [ linux-3.14.79 ] ~ [ linux-3.13.11 ] ~ [ linux-3.12.74 ] ~ [ linux-3.11.10 ] ~ [ linux-3.10.108 ] ~ [ linux-3.9.11 ] ~ [ linux-3.8.13 ] ~ [ linux-3.7.10 ] ~ [ linux-3.6.11 ] ~ [ linux-3.5.7 ] ~ [ linux-3.4.113 ] ~ [ linux-3.3.8 ] ~ [ linux-3.2.102 ] ~ [ linux-3.1.10 ] ~ [ linux-3.0.101 ] ~ [ linux-2.6.32.71 ] ~ [ linux-2.6.0 ] ~ [ linux-2.4.37.11 ] ~ [ unix-v6-master ] ~ [ ccs-tools-1.8.5 ] ~ [ policy-sample ] ~
Architecture: ~ [ i386 ] ~ [ alpha ] ~ [ m68k ] ~ [ mips ] ~ [ ppc ] ~ [ sparc ] ~ [ sparc64 ] ~

  1 // SPDX-License-Identifier: GPL-2.0
  2 /*
  3  *  linux/arch/parisc/traps.c
  4  *
  5  *  Copyright (C) 1991, 1992  Linus Torvalds
  6  *  Copyright (C) 1999, 2000  Philipp Rumpf <prumpf@tux.org>
  7  */
  8 
  9 /*
 10  * 'Traps.c' handles hardware traps and faults after we have saved some
 11  * state in 'asm.s'.
 12  */
 13 
 14 #include <linux/sched.h>
 15 #include <linux/sched/debug.h>
 16 #include <linux/kernel.h>
 17 #include <linux/string.h>
 18 #include <linux/errno.h>
 19 #include <linux/ptrace.h>
 20 #include <linux/timer.h>
 21 #include <linux/delay.h>
 22 #include <linux/mm.h>
 23 #include <linux/module.h>
 24 #include <linux/smp.h>
 25 #include <linux/spinlock.h>
 26 #include <linux/init.h>
 27 #include <linux/interrupt.h>
 28 #include <linux/console.h>
 29 #include <linux/bug.h>
 30 #include <linux/ratelimit.h>
 31 #include <linux/uaccess.h>
 32 
 33 #include <asm/assembly.h>
 34 #include <asm/io.h>
 35 #include <asm/irq.h>
 36 #include <asm/traps.h>
 37 #include <asm/unaligned.h>
 38 #include <linux/atomic.h>
 39 #include <asm/smp.h>
 40 #include <asm/pdc.h>
 41 #include <asm/pdc_chassis.h>
 42 #include <asm/unwind.h>
 43 #include <asm/tlbflush.h>
 44 #include <asm/cacheflush.h>
 45 
 46 #include "../math-emu/math-emu.h"       /* for handle_fpe() */
 47 
 48 static void parisc_show_stack(struct task_struct *task, unsigned long *sp,
 49         struct pt_regs *regs);
 50 
 51 static int printbinary(char *buf, unsigned long x, int nbits)
 52 {
 53         unsigned long mask = 1UL << (nbits - 1);
 54         while (mask != 0) {
 55                 *buf++ = (mask & x ? '1' : '');
 56                 mask >>= 1;
 57         }
 58         *buf = '\0';
 59 
 60         return nbits;
 61 }
 62 
 63 #ifdef CONFIG_64BIT
 64 #define RFMT "%016lx"
 65 #else
 66 #define RFMT "%08lx"
 67 #endif
 68 #define FFMT "%016llx"  /* fpregs are 64-bit always */
 69 
 70 #define PRINTREGS(lvl,r,f,fmt,x)        \
 71         printk("%s%s%02d-%02d  " fmt " " fmt " " fmt " " fmt "\n",      \
 72                 lvl, f, (x), (x+3), (r)[(x)+0], (r)[(x)+1],             \
 73                 (r)[(x)+2], (r)[(x)+3])
 74 
 75 static void print_gr(char *level, struct pt_regs *regs)
 76 {
 77         int i;
 78         char buf[64];
 79 
 80         printk("%s\n", level);
 81         printk("%s     YZrvWESTHLNXBCVMcbcbcbcbOGFRQPDI\n", level);
 82         printbinary(buf, regs->gr[0], 32);
 83         printk("%sPSW: %s %s\n", level, buf, print_tainted());
 84 
 85         for (i = 0; i < 32; i += 4)
 86                 PRINTREGS(level, regs->gr, "r", RFMT, i);
 87 }
 88 
 89 static void print_fr(char *level, struct pt_regs *regs)
 90 {
 91         int i;
 92         char buf[64];
 93         struct { u32 sw[2]; } s;
 94 
 95         /* FR are 64bit everywhere. Need to use asm to get the content
 96          * of fpsr/fper1, and we assume that we won't have a FP Identify
 97          * in our way, otherwise we're screwed.
 98          * The fldd is used to restore the T-bit if there was one, as the
 99          * store clears it anyway.
100          * PA2.0 book says "thou shall not use fstw on FPSR/FPERs" - T-Bone */
101         asm volatile ("fstd %%fr0,0(%1) \n\t"
102                       "fldd 0(%1),%%fr0 \n\t"
103                       : "=m" (s) : "r" (&s) : "r0");
104 
105         printk("%s\n", level);
106         printk("%s      VZOUICununcqcqcqcqcqcrmunTDVZOUI\n", level);
107         printbinary(buf, s.sw[0], 32);
108         printk("%sFPSR: %s\n", level, buf);
109         printk("%sFPER1: %08x\n", level, s.sw[1]);
110 
111         /* here we'll print fr0 again, tho it'll be meaningless */
112         for (i = 0; i < 32; i += 4)
113                 PRINTREGS(level, regs->fr, "fr", FFMT, i);
114 }
115 
116 void show_regs(struct pt_regs *regs)
117 {
118         int i, user;
119         char *level;
120         unsigned long cr30, cr31;
121 
122         user = user_mode(regs);
123         level = user ? KERN_DEBUG : KERN_CRIT;
124 
125         show_regs_print_info(level);
126 
127         print_gr(level, regs);
128 
129         for (i = 0; i < 8; i += 4)
130                 PRINTREGS(level, regs->sr, "sr", RFMT, i);
131 
132         if (user)
133                 print_fr(level, regs);
134 
135         cr30 = mfctl(30);
136         cr31 = mfctl(31);
137         printk("%s\n", level);
138         printk("%sIASQ: " RFMT " " RFMT " IAOQ: " RFMT " " RFMT "\n",
139                level, regs->iasq[0], regs->iasq[1], regs->iaoq[0], regs->iaoq[1]);
140         printk("%s IIR: %08lx    ISR: " RFMT "  IOR: " RFMT "\n",
141                level, regs->iir, regs->isr, regs->ior);
142         printk("%s CPU: %8d   CR30: " RFMT " CR31: " RFMT "\n",
143                level, current_thread_info()->cpu, cr30, cr31);
144         printk("%s ORIG_R28: " RFMT "\n", level, regs->orig_r28);
145 
146         if (user) {
147                 printk("%s IAOQ[0]: " RFMT "\n", level, regs->iaoq[0]);
148                 printk("%s IAOQ[1]: " RFMT "\n", level, regs->iaoq[1]);
149                 printk("%s RP(r2): " RFMT "\n", level, regs->gr[2]);
150         } else {
151                 printk("%s IAOQ[0]: %pS\n", level, (void *) regs->iaoq[0]);
152                 printk("%s IAOQ[1]: %pS\n", level, (void *) regs->iaoq[1]);
153                 printk("%s RP(r2): %pS\n", level, (void *) regs->gr[2]);
154 
155                 parisc_show_stack(current, NULL, regs);
156         }
157 }
158 
159 static DEFINE_RATELIMIT_STATE(_hppa_rs,
160         DEFAULT_RATELIMIT_INTERVAL, DEFAULT_RATELIMIT_BURST);
161 
162 #define parisc_printk_ratelimited(critical, regs, fmt, ...)     {             \
163         if ((critical || show_unhandled_signals) && __ratelimit(&_hppa_rs)) { \
164                 printk(fmt, ##__VA_ARGS__);                                   \
165                 show_regs(regs);                                              \
166         }                                                                     \
167 }
168 
169 
170 static void do_show_stack(struct unwind_frame_info *info)
171 {
172         int i = 1;
173 
174         printk(KERN_CRIT "Backtrace:\n");
175         while (i <= 16) {
176                 if (unwind_once(info) < 0 || info->ip == 0)
177                         break;
178 
179                 if (__kernel_text_address(info->ip)) {
180                         printk(KERN_CRIT " [<" RFMT ">] %pS\n",
181                                 info->ip, (void *) info->ip);
182                         i++;
183                 }
184         }
185         printk(KERN_CRIT "\n");
186 }
187 
188 static void parisc_show_stack(struct task_struct *task, unsigned long *sp,
189         struct pt_regs *regs)
190 {
191         struct unwind_frame_info info;
192         struct task_struct *t;
193 
194         t = task ? task : current;
195         if (regs) {
196                 unwind_frame_init(&info, t, regs);
197                 goto show_stack;
198         }
199 
200         if (t == current) {
201                 unsigned long sp;
202 
203 HERE:
204                 asm volatile ("copy %%r30, %0" : "=r"(sp));
205                 {
206                         struct pt_regs r;
207 
208                         memset(&r, 0, sizeof(struct pt_regs));
209                         r.iaoq[0] = (unsigned long)&&HERE;
210                         r.gr[2] = (unsigned long)__builtin_return_address(0);
211                         r.gr[30] = sp;
212 
213                         unwind_frame_init(&info, current, &r);
214                 }
215         } else {
216                 unwind_frame_init_from_blocked_task(&info, t);
217         }
218 
219 show_stack:
220         do_show_stack(&info);
221 }
222 
223 void show_stack(struct task_struct *t, unsigned long *sp)
224 {
225         return parisc_show_stack(t, sp, NULL);
226 }
227 
228 int is_valid_bugaddr(unsigned long iaoq)
229 {
230         return 1;
231 }
232 
233 void die_if_kernel(char *str, struct pt_regs *regs, long err)
234 {
235         if (user_mode(regs)) {
236                 if (err == 0)
237                         return; /* STFU */
238 
239                 parisc_printk_ratelimited(1, regs,
240                         KERN_CRIT "%s (pid %d): %s (code %ld) at " RFMT "\n",
241                         current->comm, task_pid_nr(current), str, err, regs->iaoq[0]);
242 
243                 return;
244         }
245 
246         oops_in_progress = 1;
247 
248         oops_enter();
249 
250         /* Amuse the user in a SPARC fashion */
251         if (err) printk(KERN_CRIT
252                         "      _______________________________ \n"
253                         "     < Your System ate a SPARC! Gah! >\n"
254                         "      ------------------------------- \n"
255                         "             \\   ^__^\n"
256                         "                 (__)\\       )\\/\\\n"
257                         "                  U  ||----w |\n"
258                         "                     ||     ||\n");
259         
260         /* unlock the pdc lock if necessary */
261         pdc_emergency_unlock();
262 
263         /* maybe the kernel hasn't booted very far yet and hasn't been able 
264          * to initialize the serial or STI console. In that case we should 
265          * re-enable the pdc console, so that the user will be able to 
266          * identify the problem. */
267         if (!console_drivers)
268                 pdc_console_restart();
269         
270         if (err)
271                 printk(KERN_CRIT "%s (pid %d): %s (code %ld)\n",
272                         current->comm, task_pid_nr(current), str, err);
273 
274         /* Wot's wrong wif bein' racy? */
275         if (current->thread.flags & PARISC_KERNEL_DEATH) {
276                 printk(KERN_CRIT "%s() recursion detected.\n", __func__);
277                 local_irq_enable();
278                 while (1);
279         }
280         current->thread.flags |= PARISC_KERNEL_DEATH;
281 
282         show_regs(regs);
283         dump_stack();
284         add_taint(TAINT_DIE, LOCKDEP_NOW_UNRELIABLE);
285 
286         if (in_interrupt())
287                 panic("Fatal exception in interrupt");
288 
289         if (panic_on_oops)
290                 panic("Fatal exception");
291 
292         oops_exit();
293         do_exit(SIGSEGV);
294 }
295 
296 /* gdb uses break 4,8 */
297 #define GDB_BREAK_INSN 0x10004
298 static void handle_gdb_break(struct pt_regs *regs, int wot)
299 {
300         struct siginfo si;
301 
302         si.si_signo = SIGTRAP;
303         si.si_errno = 0;
304         si.si_code = wot;
305         si.si_addr = (void __user *) (regs->iaoq[0] & ~3);
306         force_sig_info(SIGTRAP, &si, current);
307 }
308 
309 static void handle_break(struct pt_regs *regs)
310 {
311         unsigned iir = regs->iir;
312 
313         if (unlikely(iir == PARISC_BUG_BREAK_INSN && !user_mode(regs))) {
314                 /* check if a BUG() or WARN() trapped here.  */
315                 enum bug_trap_type tt;
316                 tt = report_bug(regs->iaoq[0] & ~3, regs);
317                 if (tt == BUG_TRAP_TYPE_WARN) {
318                         regs->iaoq[0] += 4;
319                         regs->iaoq[1] += 4;
320                         return; /* return to next instruction when WARN_ON().  */
321                 }
322                 die_if_kernel("Unknown kernel breakpoint", regs,
323                         (tt == BUG_TRAP_TYPE_NONE) ? 9 : 0);
324         }
325 
326         if (unlikely(iir != GDB_BREAK_INSN))
327                 parisc_printk_ratelimited(0, regs,
328                         KERN_DEBUG "break %d,%d: pid=%d command='%s'\n",
329                         iir & 31, (iir>>13) & ((1<<13)-1),
330                         task_pid_nr(current), current->comm);
331 
332         /* send standard GDB signal */
333         handle_gdb_break(regs, TRAP_BRKPT);
334 }
335 
336 static void default_trap(int code, struct pt_regs *regs)
337 {
338         printk(KERN_ERR "Trap %d on CPU %d\n", code, smp_processor_id());
339         show_regs(regs);
340 }
341 
342 void (*cpu_lpmc) (int code, struct pt_regs *regs) __read_mostly = default_trap;
343 
344 
345 void transfer_pim_to_trap_frame(struct pt_regs *regs)
346 {
347     register int i;
348     extern unsigned int hpmc_pim_data[];
349     struct pdc_hpmc_pim_11 *pim_narrow;
350     struct pdc_hpmc_pim_20 *pim_wide;
351 
352     if (boot_cpu_data.cpu_type >= pcxu) {
353 
354         pim_wide = (struct pdc_hpmc_pim_20 *)hpmc_pim_data;
355 
356         /*
357          * Note: The following code will probably generate a
358          * bunch of truncation error warnings from the compiler.
359          * Could be handled with an ifdef, but perhaps there
360          * is a better way.
361          */
362 
363         regs->gr[0] = pim_wide->cr[22];
364 
365         for (i = 1; i < 32; i++)
366             regs->gr[i] = pim_wide->gr[i];
367 
368         for (i = 0; i < 32; i++)
369             regs->fr[i] = pim_wide->fr[i];
370 
371         for (i = 0; i < 8; i++)
372             regs->sr[i] = pim_wide->sr[i];
373 
374         regs->iasq[0] = pim_wide->cr[17];
375         regs->iasq[1] = pim_wide->iasq_back;
376         regs->iaoq[0] = pim_wide->cr[18];
377         regs->iaoq[1] = pim_wide->iaoq_back;
378 
379         regs->sar  = pim_wide->cr[11];
380         regs->iir  = pim_wide->cr[19];
381         regs->isr  = pim_wide->cr[20];
382         regs->ior  = pim_wide->cr[21];
383     }
384     else {
385         pim_narrow = (struct pdc_hpmc_pim_11 *)hpmc_pim_data;
386 
387         regs->gr[0] = pim_narrow->cr[22];
388 
389         for (i = 1; i < 32; i++)
390             regs->gr[i] = pim_narrow->gr[i];
391 
392         for (i = 0; i < 32; i++)
393             regs->fr[i] = pim_narrow->fr[i];
394 
395         for (i = 0; i < 8; i++)
396             regs->sr[i] = pim_narrow->sr[i];
397 
398         regs->iasq[0] = pim_narrow->cr[17];
399         regs->iasq[1] = pim_narrow->iasq_back;
400         regs->iaoq[0] = pim_narrow->cr[18];
401         regs->iaoq[1] = pim_narrow->iaoq_back;
402 
403         regs->sar  = pim_narrow->cr[11];
404         regs->iir  = pim_narrow->cr[19];
405         regs->isr  = pim_narrow->cr[20];
406         regs->ior  = pim_narrow->cr[21];
407     }
408 
409     /*
410      * The following fields only have meaning if we came through
411      * another path. So just zero them here.
412      */
413 
414     regs->ksp = 0;
415     regs->kpc = 0;
416     regs->orig_r28 = 0;
417 }
418 
419 
420 /*
421  * This routine is called as a last resort when everything else
422  * has gone clearly wrong. We get called for faults in kernel space,
423  * and HPMC's.
424  */
425 void parisc_terminate(char *msg, struct pt_regs *regs, int code, unsigned long offset)
426 {
427         static DEFINE_SPINLOCK(terminate_lock);
428 
429         oops_in_progress = 1;
430 
431         set_eiem(0);
432         local_irq_disable();
433         spin_lock(&terminate_lock);
434 
435         /* unlock the pdc lock if necessary */
436         pdc_emergency_unlock();
437 
438         /* restart pdc console if necessary */
439         if (!console_drivers)
440                 pdc_console_restart();
441 
442         /* Not all paths will gutter the processor... */
443         switch(code){
444 
445         case 1:
446                 transfer_pim_to_trap_frame(regs);
447                 break;
448 
449         default:
450                 /* Fall through */
451                 break;
452 
453         }
454             
455         {
456                 /* show_stack(NULL, (unsigned long *)regs->gr[30]); */
457                 struct unwind_frame_info info;
458                 unwind_frame_init(&info, current, regs);
459                 do_show_stack(&info);
460         }
461 
462         printk("\n");
463         pr_crit("%s: Code=%d (%s) regs=%p (Addr=" RFMT ")\n",
464                 msg, code, trap_name(code), regs, offset);
465         show_regs(regs);
466 
467         spin_unlock(&terminate_lock);
468 
469         /* put soft power button back under hardware control;
470          * if the user had pressed it once at any time, the 
471          * system will shut down immediately right here. */
472         pdc_soft_power_button(0);
473         
474         /* Call kernel panic() so reboot timeouts work properly 
475          * FIXME: This function should be on the list of
476          * panic notifiers, and we should call panic
477          * directly from the location that we wish. 
478          * e.g. We should not call panic from
479          * parisc_terminate, but rather the oter way around.
480          * This hack works, prints the panic message twice,
481          * and it enables reboot timers!
482          */
483         panic(msg);
484 }
485 
486 void notrace handle_interruption(int code, struct pt_regs *regs)
487 {
488         unsigned long fault_address = 0;
489         unsigned long fault_space = 0;
490         struct siginfo si;
491 
492         if (code == 1)
493             pdc_console_restart();  /* switch back to pdc if HPMC */
494         else
495             local_irq_enable();
496 
497         /* Security check:
498          * If the priority level is still user, and the
499          * faulting space is not equal to the active space
500          * then the user is attempting something in a space
501          * that does not belong to them. Kill the process.
502          *
503          * This is normally the situation when the user
504          * attempts to jump into the kernel space at the
505          * wrong offset, be it at the gateway page or a
506          * random location.
507          *
508          * We cannot normally signal the process because it
509          * could *be* on the gateway page, and processes
510          * executing on the gateway page can't have signals
511          * delivered.
512          * 
513          * We merely readjust the address into the users
514          * space, at a destination address of zero, and
515          * allow processing to continue.
516          */
517         if (((unsigned long)regs->iaoq[0] & 3) &&
518             ((unsigned long)regs->iasq[0] != (unsigned long)regs->sr[7])) { 
519                 /* Kill the user process later */
520                 regs->iaoq[0] = 0 | 3;
521                 regs->iaoq[1] = regs->iaoq[0] + 4;
522                 regs->iasq[0] = regs->iasq[1] = regs->sr[7];
523                 regs->gr[0] &= ~PSW_B;
524                 return;
525         }
526         
527 #if 0
528         printk(KERN_CRIT "Interruption # %d\n", code);
529 #endif
530 
531         switch(code) {
532 
533         case  1:
534                 /* High-priority machine check (HPMC) */
535                 
536                 /* set up a new led state on systems shipped with a LED State panel */
537                 pdc_chassis_send_status(PDC_CHASSIS_DIRECT_HPMC);
538 
539                 parisc_terminate("High Priority Machine Check (HPMC)",
540                                 regs, code, 0);
541                 /* NOT REACHED */
542                 
543         case  2:
544                 /* Power failure interrupt */
545                 printk(KERN_CRIT "Power failure interrupt !\n");
546                 return;
547 
548         case  3:
549                 /* Recovery counter trap */
550                 regs->gr[0] &= ~PSW_R;
551                 if (user_space(regs))
552                         handle_gdb_break(regs, TRAP_TRACE);
553                 /* else this must be the start of a syscall - just let it run */
554                 return;
555 
556         case  5:
557                 /* Low-priority machine check */
558                 pdc_chassis_send_status(PDC_CHASSIS_DIRECT_LPMC);
559                 
560                 flush_cache_all();
561                 flush_tlb_all();
562                 cpu_lpmc(5, regs);
563                 return;
564 
565         case  6:
566                 /* Instruction TLB miss fault/Instruction page fault */
567                 fault_address = regs->iaoq[0];
568                 fault_space   = regs->iasq[0];
569                 break;
570 
571         case  8:
572                 /* Illegal instruction trap */
573                 die_if_kernel("Illegal instruction", regs, code);
574                 si.si_code = ILL_ILLOPC;
575                 goto give_sigill;
576 
577         case  9:
578                 /* Break instruction trap */
579                 handle_break(regs);
580                 return;
581 
582         case 10:
583                 /* Privileged operation trap */
584                 die_if_kernel("Privileged operation", regs, code);
585                 si.si_code = ILL_PRVOPC;
586                 goto give_sigill;
587 
588         case 11:
589                 /* Privileged register trap */
590                 if ((regs->iir & 0xffdfffe0) == 0x034008a0) {
591 
592                         /* This is a MFCTL cr26/cr27 to gr instruction.
593                          * PCXS traps on this, so we need to emulate it.
594                          */
595 
596                         if (regs->iir & 0x00200000)
597                                 regs->gr[regs->iir & 0x1f] = mfctl(27);
598                         else
599                                 regs->gr[regs->iir & 0x1f] = mfctl(26);
600 
601                         regs->iaoq[0] = regs->iaoq[1];
602                         regs->iaoq[1] += 4;
603                         regs->iasq[0] = regs->iasq[1];
604                         return;
605                 }
606 
607                 die_if_kernel("Privileged register usage", regs, code);
608                 si.si_code = ILL_PRVREG;
609         give_sigill:
610                 si.si_signo = SIGILL;
611                 si.si_errno = 0;
612                 si.si_addr = (void __user *) regs->iaoq[0];
613                 force_sig_info(SIGILL, &si, current);
614                 return;
615 
616         case 12:
617                 /* Overflow Trap, let the userland signal handler do the cleanup */
618                 si.si_signo = SIGFPE;
619                 si.si_code = FPE_INTOVF;
620                 si.si_addr = (void __user *) regs->iaoq[0];
621                 force_sig_info(SIGFPE, &si, current);
622                 return;
623                 
624         case 13:
625                 /* Conditional Trap
626                    The condition succeeds in an instruction which traps
627                    on condition  */
628                 if(user_mode(regs)){
629                         si.si_signo = SIGFPE;
630                         /* Set to zero, and let the userspace app figure it out from
631                            the insn pointed to by si_addr */
632                         si.si_code = 0;
633                         si.si_addr = (void __user *) regs->iaoq[0];
634                         force_sig_info(SIGFPE, &si, current);
635                         return;
636                 } 
637                 /* The kernel doesn't want to handle condition codes */
638                 break;
639                 
640         case 14:
641                 /* Assist Exception Trap, i.e. floating point exception. */
642                 die_if_kernel("Floating point exception", regs, 0); /* quiet */
643                 __inc_irq_stat(irq_fpassist_count);
644                 handle_fpe(regs);
645                 return;
646 
647         case 15:
648                 /* Data TLB miss fault/Data page fault */
649                 /* Fall through */
650         case 16:
651                 /* Non-access instruction TLB miss fault */
652                 /* The instruction TLB entry needed for the target address of the FIC
653                    is absent, and hardware can't find it, so we get to cleanup */
654                 /* Fall through */
655         case 17:
656                 /* Non-access data TLB miss fault/Non-access data page fault */
657                 /* FIXME: 
658                          Still need to add slow path emulation code here!
659                          If the insn used a non-shadow register, then the tlb
660                          handlers could not have their side-effect (e.g. probe
661                          writing to a target register) emulated since rfir would
662                          erase the changes to said register. Instead we have to
663                          setup everything, call this function we are in, and emulate
664                          by hand. Technically we need to emulate:
665                          fdc,fdce,pdc,"fic,4f",prober,probeir,probew, probeiw
666                 */
667                 fault_address = regs->ior;
668                 fault_space = regs->isr;
669                 break;
670 
671         case 18:
672                 /* PCXS only -- later cpu's split this into types 26,27 & 28 */
673                 /* Check for unaligned access */
674                 if (check_unaligned(regs)) {
675                         handle_unaligned(regs);
676                         return;
677                 }
678                 /* Fall Through */
679         case 26: 
680                 /* PCXL: Data memory access rights trap */
681                 fault_address = regs->ior;
682                 fault_space   = regs->isr;
683                 break;
684 
685         case 19:
686                 /* Data memory break trap */
687                 regs->gr[0] |= PSW_X; /* So we can single-step over the trap */
688                 /* fall thru */
689         case 21:
690                 /* Page reference trap */
691                 handle_gdb_break(regs, TRAP_HWBKPT);
692                 return;
693 
694         case 25:
695                 /* Taken branch trap */
696                 regs->gr[0] &= ~PSW_T;
697                 if (user_space(regs))
698                         handle_gdb_break(regs, TRAP_BRANCH);
699                 /* else this must be the start of a syscall - just let it
700                  * run.
701                  */
702                 return;
703 
704         case  7:  
705                 /* Instruction access rights */
706                 /* PCXL: Instruction memory protection trap */
707 
708                 /*
709                  * This could be caused by either: 1) a process attempting
710                  * to execute within a vma that does not have execute
711                  * permission, or 2) an access rights violation caused by a
712                  * flush only translation set up by ptep_get_and_clear().
713                  * So we check the vma permissions to differentiate the two.
714                  * If the vma indicates we have execute permission, then
715                  * the cause is the latter one. In this case, we need to
716                  * call do_page_fault() to fix the problem.
717                  */
718 
719                 if (user_mode(regs)) {
720                         struct vm_area_struct *vma;
721 
722                         down_read(&current->mm->mmap_sem);
723                         vma = find_vma(current->mm,regs->iaoq[0]);
724                         if (vma && (regs->iaoq[0] >= vma->vm_start)
725                                 && (vma->vm_flags & VM_EXEC)) {
726 
727                                 fault_address = regs->iaoq[0];
728                                 fault_space = regs->iasq[0];
729 
730                                 up_read(&current->mm->mmap_sem);
731                                 break; /* call do_page_fault() */
732                         }
733                         up_read(&current->mm->mmap_sem);
734                 }
735                 /* Fall Through */
736         case 27: 
737                 /* Data memory protection ID trap */
738                 if (code == 27 && !user_mode(regs) &&
739                         fixup_exception(regs))
740                         return;
741 
742                 die_if_kernel("Protection id trap", regs, code);
743                 si.si_code = SEGV_MAPERR;
744                 si.si_signo = SIGSEGV;
745                 si.si_errno = 0;
746                 if (code == 7)
747                     si.si_addr = (void __user *) regs->iaoq[0];
748                 else
749                     si.si_addr = (void __user *) regs->ior;
750                 force_sig_info(SIGSEGV, &si, current);
751                 return;
752 
753         case 28: 
754                 /* Unaligned data reference trap */
755                 handle_unaligned(regs);
756                 return;
757 
758         default:
759                 if (user_mode(regs)) {
760                         parisc_printk_ratelimited(0, regs, KERN_DEBUG
761                                 "handle_interruption() pid=%d command='%s'\n",
762                                 task_pid_nr(current), current->comm);
763                         /* SIGBUS, for lack of a better one. */
764                         si.si_signo = SIGBUS;
765                         si.si_code = BUS_OBJERR;
766                         si.si_errno = 0;
767                         si.si_addr = (void __user *) regs->ior;
768                         force_sig_info(SIGBUS, &si, current);
769                         return;
770                 }
771                 pdc_chassis_send_status(PDC_CHASSIS_DIRECT_PANIC);
772                 
773                 parisc_terminate("Unexpected interruption", regs, code, 0);
774                 /* NOT REACHED */
775         }
776 
777         if (user_mode(regs)) {
778             if ((fault_space >> SPACEID_SHIFT) != (regs->sr[7] >> SPACEID_SHIFT)) {
779                 parisc_printk_ratelimited(0, regs, KERN_DEBUG
780                                 "User fault %d on space 0x%08lx, pid=%d command='%s'\n",
781                                 code, fault_space,
782                                 task_pid_nr(current), current->comm);
783                 si.si_signo = SIGSEGV;
784                 si.si_errno = 0;
785                 si.si_code = SEGV_MAPERR;
786                 si.si_addr = (void __user *) regs->ior;
787                 force_sig_info(SIGSEGV, &si, current);
788                 return;
789             }
790         }
791         else {
792 
793             /*
794              * The kernel should never fault on its own address space,
795              * unless pagefault_disable() was called before.
796              */
797 
798             if (fault_space == 0 && !faulthandler_disabled())
799             {
800                 /* Clean up and return if in exception table. */
801                 if (fixup_exception(regs))
802                         return;
803                 pdc_chassis_send_status(PDC_CHASSIS_DIRECT_PANIC);
804                 parisc_terminate("Kernel Fault", regs, code, fault_address);
805             }
806         }
807 
808         do_page_fault(regs, code, fault_address);
809 }
810 
811 
812 void __init initialize_ivt(const void *iva)
813 {
814         extern u32 os_hpmc_size;
815         extern const u32 os_hpmc[];
816 
817         int i;
818         u32 check = 0;
819         u32 *ivap;
820         u32 *hpmcp;
821         u32 length, instr;
822 
823         if (strcmp((const char *)iva, "cows can fly"))
824                 panic("IVT invalid");
825 
826         ivap = (u32 *)iva;
827 
828         for (i = 0; i < 8; i++)
829             *ivap++ = 0;
830 
831         /*
832          * Use PDC_INSTR firmware function to get instruction that invokes
833          * PDCE_CHECK in HPMC handler.  See programming note at page 1-31 of
834          * the PA 1.1 Firmware Architecture document.
835          */
836         if (pdc_instr(&instr) == PDC_OK)
837                 ivap[0] = instr;
838 
839         /* Compute Checksum for HPMC handler */
840         length = os_hpmc_size;
841         ivap[7] = length;
842 
843         hpmcp = (u32 *)os_hpmc;
844 
845         for (i=0; i<length/4; i++)
846             check += *hpmcp++;
847 
848         for (i=0; i<8; i++)
849             check += ivap[i];
850 
851         ivap[5] = -check;
852 }
853         
854 
855 /* early_trap_init() is called before we set up kernel mappings and
856  * write-protect the kernel */
857 void  __init early_trap_init(void)
858 {
859         extern const void fault_vector_20;
860 
861 #ifndef CONFIG_64BIT
862         extern const void fault_vector_11;
863         initialize_ivt(&fault_vector_11);
864 #endif
865 
866         initialize_ivt(&fault_vector_20);
867 }
868 
869 void __init trap_init(void)
870 {
871 }
872 

~ [ source navigation ] ~ [ diff markup ] ~ [ identifier search ] ~

kernel.org | git.kernel.org | LWN.net | Project Home | Wiki (Japanese) | Wiki (English) | SVN repository | Mail admin

Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.

osdn.jp