Commit | Line | Data |
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1da177e4 LT |
1 | /* |
2 | * arch/alpha/kernel/traps.c | |
3 | * | |
4 | * (C) Copyright 1994 Linus Torvalds | |
5 | */ | |
6 | ||
7 | /* | |
8 | * This file initializes the trap entry points | |
9 | */ | |
10 | ||
11 | #include <linux/config.h> | |
12 | #include <linux/mm.h> | |
13 | #include <linux/sched.h> | |
14 | #include <linux/tty.h> | |
15 | #include <linux/delay.h> | |
16 | #include <linux/smp_lock.h> | |
17 | #include <linux/module.h> | |
18 | #include <linux/init.h> | |
19 | #include <linux/kallsyms.h> | |
20 | ||
21 | #include <asm/gentrap.h> | |
22 | #include <asm/uaccess.h> | |
23 | #include <asm/unaligned.h> | |
24 | #include <asm/sysinfo.h> | |
25 | #include <asm/hwrpb.h> | |
26 | #include <asm/mmu_context.h> | |
27 | ||
28 | #include "proto.h" | |
29 | ||
30 | /* Work-around for some SRMs which mishandle opDEC faults. */ | |
31 | ||
32 | static int opDEC_fix; | |
33 | ||
34 | static void __init | |
35 | opDEC_check(void) | |
36 | { | |
37 | __asm__ __volatile__ ( | |
38 | /* Load the address of... */ | |
39 | " br $16, 1f\n" | |
40 | /* A stub instruction fault handler. Just add 4 to the | |
41 | pc and continue. */ | |
42 | " ldq $16, 8($sp)\n" | |
43 | " addq $16, 4, $16\n" | |
44 | " stq $16, 8($sp)\n" | |
45 | " call_pal %[rti]\n" | |
46 | /* Install the instruction fault handler. */ | |
47 | "1: lda $17, 3\n" | |
48 | " call_pal %[wrent]\n" | |
49 | /* With that in place, the fault from the round-to-minf fp | |
50 | insn will arrive either at the "lda 4" insn (bad) or one | |
51 | past that (good). This places the correct fixup in %0. */ | |
52 | " lda %[fix], 0\n" | |
53 | " cvttq/svm $f31,$f31\n" | |
54 | " lda %[fix], 4" | |
55 | : [fix] "=r" (opDEC_fix) | |
56 | : [rti] "n" (PAL_rti), [wrent] "n" (PAL_wrent) | |
57 | : "$0", "$1", "$16", "$17", "$22", "$23", "$24", "$25"); | |
58 | ||
59 | if (opDEC_fix) | |
60 | printk("opDEC fixup enabled.\n"); | |
61 | } | |
62 | ||
63 | void | |
64 | dik_show_regs(struct pt_regs *regs, unsigned long *r9_15) | |
65 | { | |
66 | printk("pc = [<%016lx>] ra = [<%016lx>] ps = %04lx %s\n", | |
67 | regs->pc, regs->r26, regs->ps, print_tainted()); | |
68 | print_symbol("pc is at %s\n", regs->pc); | |
69 | print_symbol("ra is at %s\n", regs->r26 ); | |
70 | printk("v0 = %016lx t0 = %016lx t1 = %016lx\n", | |
71 | regs->r0, regs->r1, regs->r2); | |
72 | printk("t2 = %016lx t3 = %016lx t4 = %016lx\n", | |
73 | regs->r3, regs->r4, regs->r5); | |
74 | printk("t5 = %016lx t6 = %016lx t7 = %016lx\n", | |
75 | regs->r6, regs->r7, regs->r8); | |
76 | ||
77 | if (r9_15) { | |
78 | printk("s0 = %016lx s1 = %016lx s2 = %016lx\n", | |
79 | r9_15[9], r9_15[10], r9_15[11]); | |
80 | printk("s3 = %016lx s4 = %016lx s5 = %016lx\n", | |
81 | r9_15[12], r9_15[13], r9_15[14]); | |
82 | printk("s6 = %016lx\n", r9_15[15]); | |
83 | } | |
84 | ||
85 | printk("a0 = %016lx a1 = %016lx a2 = %016lx\n", | |
86 | regs->r16, regs->r17, regs->r18); | |
87 | printk("a3 = %016lx a4 = %016lx a5 = %016lx\n", | |
88 | regs->r19, regs->r20, regs->r21); | |
89 | printk("t8 = %016lx t9 = %016lx t10= %016lx\n", | |
90 | regs->r22, regs->r23, regs->r24); | |
91 | printk("t11= %016lx pv = %016lx at = %016lx\n", | |
92 | regs->r25, regs->r27, regs->r28); | |
93 | printk("gp = %016lx sp = %p\n", regs->gp, regs+1); | |
94 | #if 0 | |
95 | __halt(); | |
96 | #endif | |
97 | } | |
98 | ||
99 | #if 0 | |
100 | static char * ireg_name[] = {"v0", "t0", "t1", "t2", "t3", "t4", "t5", "t6", | |
101 | "t7", "s0", "s1", "s2", "s3", "s4", "s5", "s6", | |
102 | "a0", "a1", "a2", "a3", "a4", "a5", "t8", "t9", | |
103 | "t10", "t11", "ra", "pv", "at", "gp", "sp", "zero"}; | |
104 | #endif | |
105 | ||
106 | static void | |
107 | dik_show_code(unsigned int *pc) | |
108 | { | |
109 | long i; | |
110 | ||
111 | printk("Code:"); | |
112 | for (i = -6; i < 2; i++) { | |
113 | unsigned int insn; | |
114 | if (__get_user(insn, (unsigned int __user *)pc + i)) | |
115 | break; | |
116 | printk("%c%08x%c", i ? ' ' : '<', insn, i ? ' ' : '>'); | |
117 | } | |
118 | printk("\n"); | |
119 | } | |
120 | ||
121 | static void | |
122 | dik_show_trace(unsigned long *sp) | |
123 | { | |
124 | long i = 0; | |
125 | printk("Trace:\n"); | |
126 | while (0x1ff8 & (unsigned long) sp) { | |
127 | extern char _stext[], _etext[]; | |
128 | unsigned long tmp = *sp; | |
129 | sp++; | |
130 | if (tmp < (unsigned long) &_stext) | |
131 | continue; | |
132 | if (tmp >= (unsigned long) &_etext) | |
133 | continue; | |
134 | printk("[<%lx>]", tmp); | |
135 | print_symbol(" %s", tmp); | |
136 | printk("\n"); | |
137 | if (i > 40) { | |
138 | printk(" ..."); | |
139 | break; | |
140 | } | |
141 | } | |
142 | printk("\n"); | |
143 | } | |
144 | ||
145 | static int kstack_depth_to_print = 24; | |
146 | ||
147 | void show_stack(struct task_struct *task, unsigned long *sp) | |
148 | { | |
149 | unsigned long *stack; | |
150 | int i; | |
151 | ||
152 | /* | |
153 | * debugging aid: "show_stack(NULL);" prints the | |
154 | * back trace for this cpu. | |
155 | */ | |
156 | if(sp==NULL) | |
157 | sp=(unsigned long*)&sp; | |
158 | ||
159 | stack = sp; | |
160 | for(i=0; i < kstack_depth_to_print; i++) { | |
161 | if (((long) stack & (THREAD_SIZE-1)) == 0) | |
162 | break; | |
163 | if (i && ((i % 4) == 0)) | |
164 | printk("\n "); | |
165 | printk("%016lx ", *stack++); | |
166 | } | |
167 | printk("\n"); | |
168 | dik_show_trace(sp); | |
169 | } | |
170 | ||
171 | void dump_stack(void) | |
172 | { | |
173 | show_stack(NULL, NULL); | |
174 | } | |
175 | ||
176 | EXPORT_SYMBOL(dump_stack); | |
177 | ||
178 | void | |
179 | die_if_kernel(char * str, struct pt_regs *regs, long err, unsigned long *r9_15) | |
180 | { | |
181 | if (regs->ps & 8) | |
182 | return; | |
183 | #ifdef CONFIG_SMP | |
184 | printk("CPU %d ", hard_smp_processor_id()); | |
185 | #endif | |
186 | printk("%s(%d): %s %ld\n", current->comm, current->pid, str, err); | |
187 | dik_show_regs(regs, r9_15); | |
188 | dik_show_trace((unsigned long *)(regs+1)); | |
189 | dik_show_code((unsigned int *)regs->pc); | |
190 | ||
191 | if (test_and_set_thread_flag (TIF_DIE_IF_KERNEL)) { | |
192 | printk("die_if_kernel recursion detected.\n"); | |
193 | local_irq_enable(); | |
194 | while (1); | |
195 | } | |
196 | do_exit(SIGSEGV); | |
197 | } | |
198 | ||
199 | #ifndef CONFIG_MATHEMU | |
200 | static long dummy_emul(void) { return 0; } | |
201 | long (*alpha_fp_emul_imprecise)(struct pt_regs *regs, unsigned long writemask) | |
202 | = (void *)dummy_emul; | |
203 | long (*alpha_fp_emul) (unsigned long pc) | |
204 | = (void *)dummy_emul; | |
205 | #else | |
206 | long alpha_fp_emul_imprecise(struct pt_regs *regs, unsigned long writemask); | |
207 | long alpha_fp_emul (unsigned long pc); | |
208 | #endif | |
209 | ||
210 | asmlinkage void | |
211 | do_entArith(unsigned long summary, unsigned long write_mask, | |
212 | struct pt_regs *regs) | |
213 | { | |
214 | long si_code = FPE_FLTINV; | |
215 | siginfo_t info; | |
216 | ||
217 | if (summary & 1) { | |
218 | /* Software-completion summary bit is set, so try to | |
219 | emulate the instruction. If the processor supports | |
220 | precise exceptions, we don't have to search. */ | |
221 | if (!amask(AMASK_PRECISE_TRAP)) | |
222 | si_code = alpha_fp_emul(regs->pc - 4); | |
223 | else | |
224 | si_code = alpha_fp_emul_imprecise(regs, write_mask); | |
225 | if (si_code == 0) | |
226 | return; | |
227 | } | |
228 | die_if_kernel("Arithmetic fault", regs, 0, NULL); | |
229 | ||
230 | info.si_signo = SIGFPE; | |
231 | info.si_errno = 0; | |
232 | info.si_code = si_code; | |
233 | info.si_addr = (void __user *) regs->pc; | |
234 | send_sig_info(SIGFPE, &info, current); | |
235 | } | |
236 | ||
237 | asmlinkage void | |
238 | do_entIF(unsigned long type, struct pt_regs *regs) | |
239 | { | |
240 | siginfo_t info; | |
241 | int signo, code; | |
242 | ||
243 | if (regs->ps == 0) { | |
244 | if (type == 1) { | |
245 | const unsigned int *data | |
246 | = (const unsigned int *) regs->pc; | |
247 | printk("Kernel bug at %s:%d\n", | |
248 | (const char *)(data[1] | (long)data[2] << 32), | |
249 | data[0]); | |
250 | } | |
251 | die_if_kernel((type == 1 ? "Kernel Bug" : "Instruction fault"), | |
252 | regs, type, NULL); | |
253 | } | |
254 | ||
255 | switch (type) { | |
256 | case 0: /* breakpoint */ | |
257 | info.si_signo = SIGTRAP; | |
258 | info.si_errno = 0; | |
259 | info.si_code = TRAP_BRKPT; | |
260 | info.si_trapno = 0; | |
261 | info.si_addr = (void __user *) regs->pc; | |
262 | ||
263 | if (ptrace_cancel_bpt(current)) { | |
264 | regs->pc -= 4; /* make pc point to former bpt */ | |
265 | } | |
266 | ||
267 | send_sig_info(SIGTRAP, &info, current); | |
268 | return; | |
269 | ||
270 | case 1: /* bugcheck */ | |
271 | info.si_signo = SIGTRAP; | |
272 | info.si_errno = 0; | |
273 | info.si_code = __SI_FAULT; | |
274 | info.si_addr = (void __user *) regs->pc; | |
275 | info.si_trapno = 0; | |
276 | send_sig_info(SIGTRAP, &info, current); | |
277 | return; | |
278 | ||
279 | case 2: /* gentrap */ | |
280 | info.si_addr = (void __user *) regs->pc; | |
281 | info.si_trapno = regs->r16; | |
282 | switch ((long) regs->r16) { | |
283 | case GEN_INTOVF: | |
284 | signo = SIGFPE; | |
285 | code = FPE_INTOVF; | |
286 | break; | |
287 | case GEN_INTDIV: | |
288 | signo = SIGFPE; | |
289 | code = FPE_INTDIV; | |
290 | break; | |
291 | case GEN_FLTOVF: | |
292 | signo = SIGFPE; | |
293 | code = FPE_FLTOVF; | |
294 | break; | |
295 | case GEN_FLTDIV: | |
296 | signo = SIGFPE; | |
297 | code = FPE_FLTDIV; | |
298 | break; | |
299 | case GEN_FLTUND: | |
300 | signo = SIGFPE; | |
301 | code = FPE_FLTUND; | |
302 | break; | |
303 | case GEN_FLTINV: | |
304 | signo = SIGFPE; | |
305 | code = FPE_FLTINV; | |
306 | break; | |
307 | case GEN_FLTINE: | |
308 | signo = SIGFPE; | |
309 | code = FPE_FLTRES; | |
310 | break; | |
311 | case GEN_ROPRAND: | |
312 | signo = SIGFPE; | |
313 | code = __SI_FAULT; | |
314 | break; | |
315 | ||
316 | case GEN_DECOVF: | |
317 | case GEN_DECDIV: | |
318 | case GEN_DECINV: | |
319 | case GEN_ASSERTERR: | |
320 | case GEN_NULPTRERR: | |
321 | case GEN_STKOVF: | |
322 | case GEN_STRLENERR: | |
323 | case GEN_SUBSTRERR: | |
324 | case GEN_RANGERR: | |
325 | case GEN_SUBRNG: | |
326 | case GEN_SUBRNG1: | |
327 | case GEN_SUBRNG2: | |
328 | case GEN_SUBRNG3: | |
329 | case GEN_SUBRNG4: | |
330 | case GEN_SUBRNG5: | |
331 | case GEN_SUBRNG6: | |
332 | case GEN_SUBRNG7: | |
333 | default: | |
334 | signo = SIGTRAP; | |
335 | code = __SI_FAULT; | |
336 | break; | |
337 | } | |
338 | ||
339 | info.si_signo = signo; | |
340 | info.si_errno = 0; | |
341 | info.si_code = code; | |
342 | info.si_addr = (void __user *) regs->pc; | |
343 | send_sig_info(signo, &info, current); | |
344 | return; | |
345 | ||
346 | case 4: /* opDEC */ | |
347 | if (implver() == IMPLVER_EV4) { | |
348 | long si_code; | |
349 | ||
350 | /* The some versions of SRM do not handle | |
351 | the opDEC properly - they return the PC of the | |
352 | opDEC fault, not the instruction after as the | |
353 | Alpha architecture requires. Here we fix it up. | |
354 | We do this by intentionally causing an opDEC | |
355 | fault during the boot sequence and testing if | |
356 | we get the correct PC. If not, we set a flag | |
357 | to correct it every time through. */ | |
358 | regs->pc += opDEC_fix; | |
359 | ||
360 | /* EV4 does not implement anything except normal | |
361 | rounding. Everything else will come here as | |
362 | an illegal instruction. Emulate them. */ | |
363 | si_code = alpha_fp_emul(regs->pc - 4); | |
364 | if (si_code == 0) | |
365 | return; | |
366 | if (si_code > 0) { | |
367 | info.si_signo = SIGFPE; | |
368 | info.si_errno = 0; | |
369 | info.si_code = si_code; | |
370 | info.si_addr = (void __user *) regs->pc; | |
371 | send_sig_info(SIGFPE, &info, current); | |
372 | return; | |
373 | } | |
374 | } | |
375 | break; | |
376 | ||
377 | case 3: /* FEN fault */ | |
378 | /* Irritating users can call PAL_clrfen to disable the | |
379 | FPU for the process. The kernel will then trap in | |
380 | do_switch_stack and undo_switch_stack when we try | |
381 | to save and restore the FP registers. | |
382 | ||
383 | Given that GCC by default generates code that uses the | |
384 | FP registers, PAL_clrfen is not useful except for DoS | |
385 | attacks. So turn the bleeding FPU back on and be done | |
386 | with it. */ | |
387 | current_thread_info()->pcb.flags |= 1; | |
388 | __reload_thread(¤t_thread_info()->pcb); | |
389 | return; | |
390 | ||
391 | case 5: /* illoc */ | |
392 | default: /* unexpected instruction-fault type */ | |
393 | ; | |
394 | } | |
395 | ||
396 | info.si_signo = SIGILL; | |
397 | info.si_errno = 0; | |
398 | info.si_code = ILL_ILLOPC; | |
399 | info.si_addr = (void __user *) regs->pc; | |
400 | send_sig_info(SIGILL, &info, current); | |
401 | } | |
402 | ||
403 | /* There is an ifdef in the PALcode in MILO that enables a | |
404 | "kernel debugging entry point" as an unprivileged call_pal. | |
405 | ||
406 | We don't want to have anything to do with it, but unfortunately | |
407 | several versions of MILO included in distributions have it enabled, | |
408 | and if we don't put something on the entry point we'll oops. */ | |
409 | ||
410 | asmlinkage void | |
411 | do_entDbg(struct pt_regs *regs) | |
412 | { | |
413 | siginfo_t info; | |
414 | ||
415 | die_if_kernel("Instruction fault", regs, 0, NULL); | |
416 | ||
417 | info.si_signo = SIGILL; | |
418 | info.si_errno = 0; | |
419 | info.si_code = ILL_ILLOPC; | |
420 | info.si_addr = (void __user *) regs->pc; | |
421 | force_sig_info(SIGILL, &info, current); | |
422 | } | |
423 | ||
424 | ||
425 | /* | |
426 | * entUna has a different register layout to be reasonably simple. It | |
427 | * needs access to all the integer registers (the kernel doesn't use | |
428 | * fp-regs), and it needs to have them in order for simpler access. | |
429 | * | |
430 | * Due to the non-standard register layout (and because we don't want | |
431 | * to handle floating-point regs), user-mode unaligned accesses are | |
432 | * handled separately by do_entUnaUser below. | |
433 | * | |
434 | * Oh, btw, we don't handle the "gp" register correctly, but if we fault | |
435 | * on a gp-register unaligned load/store, something is _very_ wrong | |
436 | * in the kernel anyway.. | |
437 | */ | |
438 | struct allregs { | |
439 | unsigned long regs[32]; | |
440 | unsigned long ps, pc, gp, a0, a1, a2; | |
441 | }; | |
442 | ||
443 | struct unaligned_stat { | |
444 | unsigned long count, va, pc; | |
445 | } unaligned[2]; | |
446 | ||
447 | ||
448 | /* Macro for exception fixup code to access integer registers. */ | |
449 | #define una_reg(r) (regs.regs[(r) >= 16 && (r) <= 18 ? (r)+19 : (r)]) | |
450 | ||
451 | ||
452 | asmlinkage void | |
453 | do_entUna(void * va, unsigned long opcode, unsigned long reg, | |
454 | unsigned long a3, unsigned long a4, unsigned long a5, | |
455 | struct allregs regs) | |
456 | { | |
457 | long error, tmp1, tmp2, tmp3, tmp4; | |
458 | unsigned long pc = regs.pc - 4; | |
459 | const struct exception_table_entry *fixup; | |
460 | ||
461 | unaligned[0].count++; | |
462 | unaligned[0].va = (unsigned long) va; | |
463 | unaligned[0].pc = pc; | |
464 | ||
465 | /* We don't want to use the generic get/put unaligned macros as | |
466 | we want to trap exceptions. Only if we actually get an | |
467 | exception will we decide whether we should have caught it. */ | |
468 | ||
469 | switch (opcode) { | |
470 | case 0x0c: /* ldwu */ | |
471 | __asm__ __volatile__( | |
472 | "1: ldq_u %1,0(%3)\n" | |
473 | "2: ldq_u %2,1(%3)\n" | |
474 | " extwl %1,%3,%1\n" | |
475 | " extwh %2,%3,%2\n" | |
476 | "3:\n" | |
477 | ".section __ex_table,\"a\"\n" | |
478 | " .long 1b - .\n" | |
479 | " lda %1,3b-1b(%0)\n" | |
480 | " .long 2b - .\n" | |
481 | " lda %2,3b-2b(%0)\n" | |
482 | ".previous" | |
483 | : "=r"(error), "=&r"(tmp1), "=&r"(tmp2) | |
484 | : "r"(va), "0"(0)); | |
485 | if (error) | |
486 | goto got_exception; | |
487 | una_reg(reg) = tmp1|tmp2; | |
488 | return; | |
489 | ||
490 | case 0x28: /* ldl */ | |
491 | __asm__ __volatile__( | |
492 | "1: ldq_u %1,0(%3)\n" | |
493 | "2: ldq_u %2,3(%3)\n" | |
494 | " extll %1,%3,%1\n" | |
495 | " extlh %2,%3,%2\n" | |
496 | "3:\n" | |
497 | ".section __ex_table,\"a\"\n" | |
498 | " .long 1b - .\n" | |
499 | " lda %1,3b-1b(%0)\n" | |
500 | " .long 2b - .\n" | |
501 | " lda %2,3b-2b(%0)\n" | |
502 | ".previous" | |
503 | : "=r"(error), "=&r"(tmp1), "=&r"(tmp2) | |
504 | : "r"(va), "0"(0)); | |
505 | if (error) | |
506 | goto got_exception; | |
507 | una_reg(reg) = (int)(tmp1|tmp2); | |
508 | return; | |
509 | ||
510 | case 0x29: /* ldq */ | |
511 | __asm__ __volatile__( | |
512 | "1: ldq_u %1,0(%3)\n" | |
513 | "2: ldq_u %2,7(%3)\n" | |
514 | " extql %1,%3,%1\n" | |
515 | " extqh %2,%3,%2\n" | |
516 | "3:\n" | |
517 | ".section __ex_table,\"a\"\n" | |
518 | " .long 1b - .\n" | |
519 | " lda %1,3b-1b(%0)\n" | |
520 | " .long 2b - .\n" | |
521 | " lda %2,3b-2b(%0)\n" | |
522 | ".previous" | |
523 | : "=r"(error), "=&r"(tmp1), "=&r"(tmp2) | |
524 | : "r"(va), "0"(0)); | |
525 | if (error) | |
526 | goto got_exception; | |
527 | una_reg(reg) = tmp1|tmp2; | |
528 | return; | |
529 | ||
530 | /* Note that the store sequences do not indicate that they change | |
531 | memory because it _should_ be affecting nothing in this context. | |
532 | (Otherwise we have other, much larger, problems.) */ | |
533 | case 0x0d: /* stw */ | |
534 | __asm__ __volatile__( | |
535 | "1: ldq_u %2,1(%5)\n" | |
536 | "2: ldq_u %1,0(%5)\n" | |
537 | " inswh %6,%5,%4\n" | |
538 | " inswl %6,%5,%3\n" | |
539 | " mskwh %2,%5,%2\n" | |
540 | " mskwl %1,%5,%1\n" | |
541 | " or %2,%4,%2\n" | |
542 | " or %1,%3,%1\n" | |
543 | "3: stq_u %2,1(%5)\n" | |
544 | "4: stq_u %1,0(%5)\n" | |
545 | "5:\n" | |
546 | ".section __ex_table,\"a\"\n" | |
547 | " .long 1b - .\n" | |
548 | " lda %2,5b-1b(%0)\n" | |
549 | " .long 2b - .\n" | |
550 | " lda %1,5b-2b(%0)\n" | |
551 | " .long 3b - .\n" | |
552 | " lda $31,5b-3b(%0)\n" | |
553 | " .long 4b - .\n" | |
554 | " lda $31,5b-4b(%0)\n" | |
555 | ".previous" | |
556 | : "=r"(error), "=&r"(tmp1), "=&r"(tmp2), | |
557 | "=&r"(tmp3), "=&r"(tmp4) | |
558 | : "r"(va), "r"(una_reg(reg)), "0"(0)); | |
559 | if (error) | |
560 | goto got_exception; | |
561 | return; | |
562 | ||
563 | case 0x2c: /* stl */ | |
564 | __asm__ __volatile__( | |
565 | "1: ldq_u %2,3(%5)\n" | |
566 | "2: ldq_u %1,0(%5)\n" | |
567 | " inslh %6,%5,%4\n" | |
568 | " insll %6,%5,%3\n" | |
569 | " msklh %2,%5,%2\n" | |
570 | " mskll %1,%5,%1\n" | |
571 | " or %2,%4,%2\n" | |
572 | " or %1,%3,%1\n" | |
573 | "3: stq_u %2,3(%5)\n" | |
574 | "4: stq_u %1,0(%5)\n" | |
575 | "5:\n" | |
576 | ".section __ex_table,\"a\"\n" | |
577 | " .long 1b - .\n" | |
578 | " lda %2,5b-1b(%0)\n" | |
579 | " .long 2b - .\n" | |
580 | " lda %1,5b-2b(%0)\n" | |
581 | " .long 3b - .\n" | |
582 | " lda $31,5b-3b(%0)\n" | |
583 | " .long 4b - .\n" | |
584 | " lda $31,5b-4b(%0)\n" | |
585 | ".previous" | |
586 | : "=r"(error), "=&r"(tmp1), "=&r"(tmp2), | |
587 | "=&r"(tmp3), "=&r"(tmp4) | |
588 | : "r"(va), "r"(una_reg(reg)), "0"(0)); | |
589 | if (error) | |
590 | goto got_exception; | |
591 | return; | |
592 | ||
593 | case 0x2d: /* stq */ | |
594 | __asm__ __volatile__( | |
595 | "1: ldq_u %2,7(%5)\n" | |
596 | "2: ldq_u %1,0(%5)\n" | |
597 | " insqh %6,%5,%4\n" | |
598 | " insql %6,%5,%3\n" | |
599 | " mskqh %2,%5,%2\n" | |
600 | " mskql %1,%5,%1\n" | |
601 | " or %2,%4,%2\n" | |
602 | " or %1,%3,%1\n" | |
603 | "3: stq_u %2,7(%5)\n" | |
604 | "4: stq_u %1,0(%5)\n" | |
605 | "5:\n" | |
606 | ".section __ex_table,\"a\"\n\t" | |
607 | " .long 1b - .\n" | |
608 | " lda %2,5b-1b(%0)\n" | |
609 | " .long 2b - .\n" | |
610 | " lda %1,5b-2b(%0)\n" | |
611 | " .long 3b - .\n" | |
612 | " lda $31,5b-3b(%0)\n" | |
613 | " .long 4b - .\n" | |
614 | " lda $31,5b-4b(%0)\n" | |
615 | ".previous" | |
616 | : "=r"(error), "=&r"(tmp1), "=&r"(tmp2), | |
617 | "=&r"(tmp3), "=&r"(tmp4) | |
618 | : "r"(va), "r"(una_reg(reg)), "0"(0)); | |
619 | if (error) | |
620 | goto got_exception; | |
621 | return; | |
622 | } | |
623 | ||
624 | lock_kernel(); | |
625 | printk("Bad unaligned kernel access at %016lx: %p %lx %ld\n", | |
626 | pc, va, opcode, reg); | |
627 | do_exit(SIGSEGV); | |
628 | ||
629 | got_exception: | |
630 | /* Ok, we caught the exception, but we don't want it. Is there | |
631 | someone to pass it along to? */ | |
632 | if ((fixup = search_exception_tables(pc)) != 0) { | |
633 | unsigned long newpc; | |
634 | newpc = fixup_exception(una_reg, fixup, pc); | |
635 | ||
636 | printk("Forwarding unaligned exception at %lx (%lx)\n", | |
637 | pc, newpc); | |
638 | ||
639 | (®s)->pc = newpc; | |
640 | return; | |
641 | } | |
642 | ||
643 | /* | |
644 | * Yikes! No one to forward the exception to. | |
645 | * Since the registers are in a weird format, dump them ourselves. | |
646 | */ | |
647 | lock_kernel(); | |
648 | ||
649 | printk("%s(%d): unhandled unaligned exception\n", | |
650 | current->comm, current->pid); | |
651 | ||
652 | printk("pc = [<%016lx>] ra = [<%016lx>] ps = %04lx\n", | |
653 | pc, una_reg(26), regs.ps); | |
654 | printk("r0 = %016lx r1 = %016lx r2 = %016lx\n", | |
655 | una_reg(0), una_reg(1), una_reg(2)); | |
656 | printk("r3 = %016lx r4 = %016lx r5 = %016lx\n", | |
657 | una_reg(3), una_reg(4), una_reg(5)); | |
658 | printk("r6 = %016lx r7 = %016lx r8 = %016lx\n", | |
659 | una_reg(6), una_reg(7), una_reg(8)); | |
660 | printk("r9 = %016lx r10= %016lx r11= %016lx\n", | |
661 | una_reg(9), una_reg(10), una_reg(11)); | |
662 | printk("r12= %016lx r13= %016lx r14= %016lx\n", | |
663 | una_reg(12), una_reg(13), una_reg(14)); | |
664 | printk("r15= %016lx\n", una_reg(15)); | |
665 | printk("r16= %016lx r17= %016lx r18= %016lx\n", | |
666 | una_reg(16), una_reg(17), una_reg(18)); | |
667 | printk("r19= %016lx r20= %016lx r21= %016lx\n", | |
668 | una_reg(19), una_reg(20), una_reg(21)); | |
669 | printk("r22= %016lx r23= %016lx r24= %016lx\n", | |
670 | una_reg(22), una_reg(23), una_reg(24)); | |
671 | printk("r25= %016lx r27= %016lx r28= %016lx\n", | |
672 | una_reg(25), una_reg(27), una_reg(28)); | |
673 | printk("gp = %016lx sp = %p\n", regs.gp, ®s+1); | |
674 | ||
675 | dik_show_code((unsigned int *)pc); | |
676 | dik_show_trace((unsigned long *)(®s+1)); | |
677 | ||
678 | if (test_and_set_thread_flag (TIF_DIE_IF_KERNEL)) { | |
679 | printk("die_if_kernel recursion detected.\n"); | |
680 | local_irq_enable(); | |
681 | while (1); | |
682 | } | |
683 | do_exit(SIGSEGV); | |
684 | } | |
685 | ||
686 | /* | |
687 | * Convert an s-floating point value in memory format to the | |
688 | * corresponding value in register format. The exponent | |
689 | * needs to be remapped to preserve non-finite values | |
690 | * (infinities, not-a-numbers, denormals). | |
691 | */ | |
692 | static inline unsigned long | |
693 | s_mem_to_reg (unsigned long s_mem) | |
694 | { | |
695 | unsigned long frac = (s_mem >> 0) & 0x7fffff; | |
696 | unsigned long sign = (s_mem >> 31) & 0x1; | |
697 | unsigned long exp_msb = (s_mem >> 30) & 0x1; | |
698 | unsigned long exp_low = (s_mem >> 23) & 0x7f; | |
699 | unsigned long exp; | |
700 | ||
701 | exp = (exp_msb << 10) | exp_low; /* common case */ | |
702 | if (exp_msb) { | |
703 | if (exp_low == 0x7f) { | |
704 | exp = 0x7ff; | |
705 | } | |
706 | } else { | |
707 | if (exp_low == 0x00) { | |
708 | exp = 0x000; | |
709 | } else { | |
710 | exp |= (0x7 << 7); | |
711 | } | |
712 | } | |
713 | return (sign << 63) | (exp << 52) | (frac << 29); | |
714 | } | |
715 | ||
716 | /* | |
717 | * Convert an s-floating point value in register format to the | |
718 | * corresponding value in memory format. | |
719 | */ | |
720 | static inline unsigned long | |
721 | s_reg_to_mem (unsigned long s_reg) | |
722 | { | |
723 | return ((s_reg >> 62) << 30) | ((s_reg << 5) >> 34); | |
724 | } | |
725 | ||
726 | /* | |
727 | * Handle user-level unaligned fault. Handling user-level unaligned | |
728 | * faults is *extremely* slow and produces nasty messages. A user | |
729 | * program *should* fix unaligned faults ASAP. | |
730 | * | |
731 | * Notice that we have (almost) the regular kernel stack layout here, | |
732 | * so finding the appropriate registers is a little more difficult | |
733 | * than in the kernel case. | |
734 | * | |
735 | * Finally, we handle regular integer load/stores only. In | |
736 | * particular, load-linked/store-conditionally and floating point | |
737 | * load/stores are not supported. The former make no sense with | |
738 | * unaligned faults (they are guaranteed to fail) and I don't think | |
739 | * the latter will occur in any decent program. | |
740 | * | |
741 | * Sigh. We *do* have to handle some FP operations, because GCC will | |
742 | * uses them as temporary storage for integer memory to memory copies. | |
743 | * However, we need to deal with stt/ldt and sts/lds only. | |
744 | */ | |
745 | ||
746 | #define OP_INT_MASK ( 1L << 0x28 | 1L << 0x2c /* ldl stl */ \ | |
747 | | 1L << 0x29 | 1L << 0x2d /* ldq stq */ \ | |
748 | | 1L << 0x0c | 1L << 0x0d /* ldwu stw */ \ | |
749 | | 1L << 0x0a | 1L << 0x0e ) /* ldbu stb */ | |
750 | ||
751 | #define OP_WRITE_MASK ( 1L << 0x26 | 1L << 0x27 /* sts stt */ \ | |
752 | | 1L << 0x2c | 1L << 0x2d /* stl stq */ \ | |
753 | | 1L << 0x0d | 1L << 0x0e ) /* stw stb */ | |
754 | ||
755 | #define R(x) ((size_t) &((struct pt_regs *)0)->x) | |
756 | ||
757 | static int unauser_reg_offsets[32] = { | |
758 | R(r0), R(r1), R(r2), R(r3), R(r4), R(r5), R(r6), R(r7), R(r8), | |
759 | /* r9 ... r15 are stored in front of regs. */ | |
760 | -56, -48, -40, -32, -24, -16, -8, | |
761 | R(r16), R(r17), R(r18), | |
762 | R(r19), R(r20), R(r21), R(r22), R(r23), R(r24), R(r25), R(r26), | |
763 | R(r27), R(r28), R(gp), | |
764 | 0, 0 | |
765 | }; | |
766 | ||
767 | #undef R | |
768 | ||
769 | asmlinkage void | |
770 | do_entUnaUser(void __user * va, unsigned long opcode, | |
771 | unsigned long reg, struct pt_regs *regs) | |
772 | { | |
773 | static int cnt = 0; | |
774 | static long last_time = 0; | |
775 | ||
776 | unsigned long tmp1, tmp2, tmp3, tmp4; | |
777 | unsigned long fake_reg, *reg_addr = &fake_reg; | |
778 | siginfo_t info; | |
779 | long error; | |
780 | ||
781 | /* Check the UAC bits to decide what the user wants us to do | |
782 | with the unaliged access. */ | |
783 | ||
784 | if (!test_thread_flag (TIF_UAC_NOPRINT)) { | |
785 | if (cnt >= 5 && jiffies - last_time > 5*HZ) { | |
786 | cnt = 0; | |
787 | } | |
788 | if (++cnt < 5) { | |
789 | printk("%s(%d): unaligned trap at %016lx: %p %lx %ld\n", | |
790 | current->comm, current->pid, | |
791 | regs->pc - 4, va, opcode, reg); | |
792 | } | |
793 | last_time = jiffies; | |
794 | } | |
795 | if (test_thread_flag (TIF_UAC_SIGBUS)) | |
796 | goto give_sigbus; | |
797 | /* Not sure why you'd want to use this, but... */ | |
798 | if (test_thread_flag (TIF_UAC_NOFIX)) | |
799 | return; | |
800 | ||
801 | /* Don't bother reading ds in the access check since we already | |
802 | know that this came from the user. Also rely on the fact that | |
803 | the page at TASK_SIZE is unmapped and so can't be touched anyway. */ | |
804 | if (!__access_ok((unsigned long)va, 0, USER_DS)) | |
805 | goto give_sigsegv; | |
806 | ||
807 | ++unaligned[1].count; | |
808 | unaligned[1].va = (unsigned long)va; | |
809 | unaligned[1].pc = regs->pc - 4; | |
810 | ||
811 | if ((1L << opcode) & OP_INT_MASK) { | |
812 | /* it's an integer load/store */ | |
813 | if (reg < 30) { | |
814 | reg_addr = (unsigned long *) | |
815 | ((char *)regs + unauser_reg_offsets[reg]); | |
816 | } else if (reg == 30) { | |
817 | /* usp in PAL regs */ | |
818 | fake_reg = rdusp(); | |
819 | } else { | |
820 | /* zero "register" */ | |
821 | fake_reg = 0; | |
822 | } | |
823 | } | |
824 | ||
825 | /* We don't want to use the generic get/put unaligned macros as | |
826 | we want to trap exceptions. Only if we actually get an | |
827 | exception will we decide whether we should have caught it. */ | |
828 | ||
829 | switch (opcode) { | |
830 | case 0x0c: /* ldwu */ | |
831 | __asm__ __volatile__( | |
832 | "1: ldq_u %1,0(%3)\n" | |
833 | "2: ldq_u %2,1(%3)\n" | |
834 | " extwl %1,%3,%1\n" | |
835 | " extwh %2,%3,%2\n" | |
836 | "3:\n" | |
837 | ".section __ex_table,\"a\"\n" | |
838 | " .long 1b - .\n" | |
839 | " lda %1,3b-1b(%0)\n" | |
840 | " .long 2b - .\n" | |
841 | " lda %2,3b-2b(%0)\n" | |
842 | ".previous" | |
843 | : "=r"(error), "=&r"(tmp1), "=&r"(tmp2) | |
844 | : "r"(va), "0"(0)); | |
845 | if (error) | |
846 | goto give_sigsegv; | |
847 | *reg_addr = tmp1|tmp2; | |
848 | break; | |
849 | ||
850 | case 0x22: /* lds */ | |
851 | __asm__ __volatile__( | |
852 | "1: ldq_u %1,0(%3)\n" | |
853 | "2: ldq_u %2,3(%3)\n" | |
854 | " extll %1,%3,%1\n" | |
855 | " extlh %2,%3,%2\n" | |
856 | "3:\n" | |
857 | ".section __ex_table,\"a\"\n" | |
858 | " .long 1b - .\n" | |
859 | " lda %1,3b-1b(%0)\n" | |
860 | " .long 2b - .\n" | |
861 | " lda %2,3b-2b(%0)\n" | |
862 | ".previous" | |
863 | : "=r"(error), "=&r"(tmp1), "=&r"(tmp2) | |
864 | : "r"(va), "0"(0)); | |
865 | if (error) | |
866 | goto give_sigsegv; | |
867 | alpha_write_fp_reg(reg, s_mem_to_reg((int)(tmp1|tmp2))); | |
868 | return; | |
869 | ||
870 | case 0x23: /* ldt */ | |
871 | __asm__ __volatile__( | |
872 | "1: ldq_u %1,0(%3)\n" | |
873 | "2: ldq_u %2,7(%3)\n" | |
874 | " extql %1,%3,%1\n" | |
875 | " extqh %2,%3,%2\n" | |
876 | "3:\n" | |
877 | ".section __ex_table,\"a\"\n" | |
878 | " .long 1b - .\n" | |
879 | " lda %1,3b-1b(%0)\n" | |
880 | " .long 2b - .\n" | |
881 | " lda %2,3b-2b(%0)\n" | |
882 | ".previous" | |
883 | : "=r"(error), "=&r"(tmp1), "=&r"(tmp2) | |
884 | : "r"(va), "0"(0)); | |
885 | if (error) | |
886 | goto give_sigsegv; | |
887 | alpha_write_fp_reg(reg, tmp1|tmp2); | |
888 | return; | |
889 | ||
890 | case 0x28: /* ldl */ | |
891 | __asm__ __volatile__( | |
892 | "1: ldq_u %1,0(%3)\n" | |
893 | "2: ldq_u %2,3(%3)\n" | |
894 | " extll %1,%3,%1\n" | |
895 | " extlh %2,%3,%2\n" | |
896 | "3:\n" | |
897 | ".section __ex_table,\"a\"\n" | |
898 | " .long 1b - .\n" | |
899 | " lda %1,3b-1b(%0)\n" | |
900 | " .long 2b - .\n" | |
901 | " lda %2,3b-2b(%0)\n" | |
902 | ".previous" | |
903 | : "=r"(error), "=&r"(tmp1), "=&r"(tmp2) | |
904 | : "r"(va), "0"(0)); | |
905 | if (error) | |
906 | goto give_sigsegv; | |
907 | *reg_addr = (int)(tmp1|tmp2); | |
908 | break; | |
909 | ||
910 | case 0x29: /* ldq */ | |
911 | __asm__ __volatile__( | |
912 | "1: ldq_u %1,0(%3)\n" | |
913 | "2: ldq_u %2,7(%3)\n" | |
914 | " extql %1,%3,%1\n" | |
915 | " extqh %2,%3,%2\n" | |
916 | "3:\n" | |
917 | ".section __ex_table,\"a\"\n" | |
918 | " .long 1b - .\n" | |
919 | " lda %1,3b-1b(%0)\n" | |
920 | " .long 2b - .\n" | |
921 | " lda %2,3b-2b(%0)\n" | |
922 | ".previous" | |
923 | : "=r"(error), "=&r"(tmp1), "=&r"(tmp2) | |
924 | : "r"(va), "0"(0)); | |
925 | if (error) | |
926 | goto give_sigsegv; | |
927 | *reg_addr = tmp1|tmp2; | |
928 | break; | |
929 | ||
930 | /* Note that the store sequences do not indicate that they change | |
931 | memory because it _should_ be affecting nothing in this context. | |
932 | (Otherwise we have other, much larger, problems.) */ | |
933 | case 0x0d: /* stw */ | |
934 | __asm__ __volatile__( | |
935 | "1: ldq_u %2,1(%5)\n" | |
936 | "2: ldq_u %1,0(%5)\n" | |
937 | " inswh %6,%5,%4\n" | |
938 | " inswl %6,%5,%3\n" | |
939 | " mskwh %2,%5,%2\n" | |
940 | " mskwl %1,%5,%1\n" | |
941 | " or %2,%4,%2\n" | |
942 | " or %1,%3,%1\n" | |
943 | "3: stq_u %2,1(%5)\n" | |
944 | "4: stq_u %1,0(%5)\n" | |
945 | "5:\n" | |
946 | ".section __ex_table,\"a\"\n" | |
947 | " .long 1b - .\n" | |
948 | " lda %2,5b-1b(%0)\n" | |
949 | " .long 2b - .\n" | |
950 | " lda %1,5b-2b(%0)\n" | |
951 | " .long 3b - .\n" | |
952 | " lda $31,5b-3b(%0)\n" | |
953 | " .long 4b - .\n" | |
954 | " lda $31,5b-4b(%0)\n" | |
955 | ".previous" | |
956 | : "=r"(error), "=&r"(tmp1), "=&r"(tmp2), | |
957 | "=&r"(tmp3), "=&r"(tmp4) | |
958 | : "r"(va), "r"(*reg_addr), "0"(0)); | |
959 | if (error) | |
960 | goto give_sigsegv; | |
961 | return; | |
962 | ||
963 | case 0x26: /* sts */ | |
964 | fake_reg = s_reg_to_mem(alpha_read_fp_reg(reg)); | |
965 | /* FALLTHRU */ | |
966 | ||
967 | case 0x2c: /* stl */ | |
968 | __asm__ __volatile__( | |
969 | "1: ldq_u %2,3(%5)\n" | |
970 | "2: ldq_u %1,0(%5)\n" | |
971 | " inslh %6,%5,%4\n" | |
972 | " insll %6,%5,%3\n" | |
973 | " msklh %2,%5,%2\n" | |
974 | " mskll %1,%5,%1\n" | |
975 | " or %2,%4,%2\n" | |
976 | " or %1,%3,%1\n" | |
977 | "3: stq_u %2,3(%5)\n" | |
978 | "4: stq_u %1,0(%5)\n" | |
979 | "5:\n" | |
980 | ".section __ex_table,\"a\"\n" | |
981 | " .long 1b - .\n" | |
982 | " lda %2,5b-1b(%0)\n" | |
983 | " .long 2b - .\n" | |
984 | " lda %1,5b-2b(%0)\n" | |
985 | " .long 3b - .\n" | |
986 | " lda $31,5b-3b(%0)\n" | |
987 | " .long 4b - .\n" | |
988 | " lda $31,5b-4b(%0)\n" | |
989 | ".previous" | |
990 | : "=r"(error), "=&r"(tmp1), "=&r"(tmp2), | |
991 | "=&r"(tmp3), "=&r"(tmp4) | |
992 | : "r"(va), "r"(*reg_addr), "0"(0)); | |
993 | if (error) | |
994 | goto give_sigsegv; | |
995 | return; | |
996 | ||
997 | case 0x27: /* stt */ | |
998 | fake_reg = alpha_read_fp_reg(reg); | |
999 | /* FALLTHRU */ | |
1000 | ||
1001 | case 0x2d: /* stq */ | |
1002 | __asm__ __volatile__( | |
1003 | "1: ldq_u %2,7(%5)\n" | |
1004 | "2: ldq_u %1,0(%5)\n" | |
1005 | " insqh %6,%5,%4\n" | |
1006 | " insql %6,%5,%3\n" | |
1007 | " mskqh %2,%5,%2\n" | |
1008 | " mskql %1,%5,%1\n" | |
1009 | " or %2,%4,%2\n" | |
1010 | " or %1,%3,%1\n" | |
1011 | "3: stq_u %2,7(%5)\n" | |
1012 | "4: stq_u %1,0(%5)\n" | |
1013 | "5:\n" | |
1014 | ".section __ex_table,\"a\"\n\t" | |
1015 | " .long 1b - .\n" | |
1016 | " lda %2,5b-1b(%0)\n" | |
1017 | " .long 2b - .\n" | |
1018 | " lda %1,5b-2b(%0)\n" | |
1019 | " .long 3b - .\n" | |
1020 | " lda $31,5b-3b(%0)\n" | |
1021 | " .long 4b - .\n" | |
1022 | " lda $31,5b-4b(%0)\n" | |
1023 | ".previous" | |
1024 | : "=r"(error), "=&r"(tmp1), "=&r"(tmp2), | |
1025 | "=&r"(tmp3), "=&r"(tmp4) | |
1026 | : "r"(va), "r"(*reg_addr), "0"(0)); | |
1027 | if (error) | |
1028 | goto give_sigsegv; | |
1029 | return; | |
1030 | ||
1031 | default: | |
1032 | /* What instruction were you trying to use, exactly? */ | |
1033 | goto give_sigbus; | |
1034 | } | |
1035 | ||
1036 | /* Only integer loads should get here; everyone else returns early. */ | |
1037 | if (reg == 30) | |
1038 | wrusp(fake_reg); | |
1039 | return; | |
1040 | ||
1041 | give_sigsegv: | |
1042 | regs->pc -= 4; /* make pc point to faulting insn */ | |
1043 | info.si_signo = SIGSEGV; | |
1044 | info.si_errno = 0; | |
1045 | ||
1046 | /* We need to replicate some of the logic in mm/fault.c, | |
1047 | since we don't have access to the fault code in the | |
1048 | exception handling return path. */ | |
1049 | if (!__access_ok((unsigned long)va, 0, USER_DS)) | |
1050 | info.si_code = SEGV_ACCERR; | |
1051 | else { | |
1052 | struct mm_struct *mm = current->mm; | |
1053 | down_read(&mm->mmap_sem); | |
1054 | if (find_vma(mm, (unsigned long)va)) | |
1055 | info.si_code = SEGV_ACCERR; | |
1056 | else | |
1057 | info.si_code = SEGV_MAPERR; | |
1058 | up_read(&mm->mmap_sem); | |
1059 | } | |
1060 | info.si_addr = va; | |
1061 | send_sig_info(SIGSEGV, &info, current); | |
1062 | return; | |
1063 | ||
1064 | give_sigbus: | |
1065 | regs->pc -= 4; | |
1066 | info.si_signo = SIGBUS; | |
1067 | info.si_errno = 0; | |
1068 | info.si_code = BUS_ADRALN; | |
1069 | info.si_addr = va; | |
1070 | send_sig_info(SIGBUS, &info, current); | |
1071 | return; | |
1072 | } | |
1073 | ||
1074 | void __init | |
1075 | trap_init(void) | |
1076 | { | |
1077 | /* Tell PAL-code what global pointer we want in the kernel. */ | |
1078 | register unsigned long gptr __asm__("$29"); | |
1079 | wrkgp(gptr); | |
1080 | ||
1081 | /* Hack for Multia (UDB) and JENSEN: some of their SRMs have | |
1082 | a bug in the handling of the opDEC fault. Fix it up if so. */ | |
1083 | if (implver() == IMPLVER_EV4) | |
1084 | opDEC_check(); | |
1085 | ||
1086 | wrent(entArith, 1); | |
1087 | wrent(entMM, 2); | |
1088 | wrent(entIF, 3); | |
1089 | wrent(entUna, 4); | |
1090 | wrent(entSys, 5); | |
1091 | wrent(entDbg, 6); | |
1092 | } |