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1/*
2 * arch/sparc/kernel/traps.c
3 *
4 * Copyright 1995, 2008 David S. Miller (davem@davemloft.net)
5 * Copyright 2000 Jakub Jelinek (jakub@redhat.com)
6 */
7
8/*
9 * I hate traps on the sparc, grrr...
10 */
11
12#include <linux/sched.h> /* for jiffies */
13#include <linux/kernel.h>
14#include <linux/signal.h>
15#include <linux/smp.h>
16#include <linux/kdebug.h>
17#include <linux/export.h>
18
19#include <asm/delay.h>
20#include <asm/ptrace.h>
21#include <asm/oplib.h>
22#include <asm/page.h>
23#include <asm/pgtable.h>
24#include <asm/unistd.h>
25#include <asm/traps.h>
26
27#include "entry.h"
28#include "kernel.h"
29
30/* #define TRAP_DEBUG */
31
32static void instruction_dump(unsigned long *pc)
33{
34 int i;
35
36 if((((unsigned long) pc) & 3))
37 return;
38
39 for(i = -3; i < 6; i++)
40 printk("%c%08lx%c",i?' ':'<',pc[i],i?' ':'>');
41 printk("\n");
42}
43
44#define __SAVE __asm__ __volatile__("save %sp, -0x40, %sp\n\t")
45#define __RESTORE __asm__ __volatile__("restore %g0, %g0, %g0\n\t")
46
47void die_if_kernel(char *str, struct pt_regs *regs)
48{
49 static int die_counter;
50 int count = 0;
51
52 /* Amuse the user. */
53 printk(
54" \\|/ ____ \\|/\n"
55" \"@'/ ,. \\`@\"\n"
56" /_| \\__/ |_\\\n"
57" \\__U_/\n");
58
59 printk("%s(%d): %s [#%d]\n", current->comm, task_pid_nr(current), str, ++die_counter);
60 show_regs(regs);
61 add_taint(TAINT_DIE);
62
63 __SAVE; __SAVE; __SAVE; __SAVE;
64 __SAVE; __SAVE; __SAVE; __SAVE;
65 __RESTORE; __RESTORE; __RESTORE; __RESTORE;
66 __RESTORE; __RESTORE; __RESTORE; __RESTORE;
67
68 {
69 struct reg_window32 *rw = (struct reg_window32 *)regs->u_regs[UREG_FP];
70
71 /* Stop the back trace when we hit userland or we
72 * find some badly aligned kernel stack. Set an upper
73 * bound in case our stack is trashed and we loop.
74 */
75 while(rw &&
76 count++ < 30 &&
77 (((unsigned long) rw) >= PAGE_OFFSET) &&
78 !(((unsigned long) rw) & 0x7)) {
79 printk("Caller[%08lx]: %pS\n", rw->ins[7],
80 (void *) rw->ins[7]);
81 rw = (struct reg_window32 *)rw->ins[6];
82 }
83 }
84 printk("Instruction DUMP:");
85 instruction_dump ((unsigned long *) regs->pc);
86 if(regs->psr & PSR_PS)
87 do_exit(SIGKILL);
88 do_exit(SIGSEGV);
89}
90
91void do_hw_interrupt(struct pt_regs *regs, unsigned long type)
92{
93 siginfo_t info;
94
95 if(type < 0x80) {
96 /* Sun OS's puke from bad traps, Linux survives! */
97 printk("Unimplemented Sparc TRAP, type = %02lx\n", type);
98 die_if_kernel("Whee... Hello Mr. Penguin", regs);
99 }
100
101 if(regs->psr & PSR_PS)
102 die_if_kernel("Kernel bad trap", regs);
103
104 info.si_signo = SIGILL;
105 info.si_errno = 0;
106 info.si_code = ILL_ILLTRP;
107 info.si_addr = (void __user *)regs->pc;
108 info.si_trapno = type - 0x80;
109 force_sig_info(SIGILL, &info, current);
110}
111
112void do_illegal_instruction(struct pt_regs *regs, unsigned long pc, unsigned long npc,
113 unsigned long psr)
114{
115 siginfo_t info;
116
117 if(psr & PSR_PS)
118 die_if_kernel("Kernel illegal instruction", regs);
119#ifdef TRAP_DEBUG
120 printk("Ill instr. at pc=%08lx instruction is %08lx\n",
121 regs->pc, *(unsigned long *)regs->pc);
122#endif
123
124 info.si_signo = SIGILL;
125 info.si_errno = 0;
126 info.si_code = ILL_ILLOPC;
127 info.si_addr = (void __user *)pc;
128 info.si_trapno = 0;
129 send_sig_info(SIGILL, &info, current);
130}
131
132void do_priv_instruction(struct pt_regs *regs, unsigned long pc, unsigned long npc,
133 unsigned long psr)
134{
135 siginfo_t info;
136
137 if(psr & PSR_PS)
138 die_if_kernel("Penguin instruction from Penguin mode??!?!", regs);
139 info.si_signo = SIGILL;
140 info.si_errno = 0;
141 info.si_code = ILL_PRVOPC;
142 info.si_addr = (void __user *)pc;
143 info.si_trapno = 0;
144 send_sig_info(SIGILL, &info, current);
145}
146
147/* XXX User may want to be allowed to do this. XXX */
148
149void do_memaccess_unaligned(struct pt_regs *regs, unsigned long pc, unsigned long npc,
150 unsigned long psr)
151{
152 siginfo_t info;
153
154 if(regs->psr & PSR_PS) {
155 printk("KERNEL MNA at pc %08lx npc %08lx called by %08lx\n", pc, npc,
156 regs->u_regs[UREG_RETPC]);
157 die_if_kernel("BOGUS", regs);
158 /* die_if_kernel("Kernel MNA access", regs); */
159 }
160#if 0
161 show_regs (regs);
162 instruction_dump ((unsigned long *) regs->pc);
163 printk ("do_MNA!\n");
164#endif
165 info.si_signo = SIGBUS;
166 info.si_errno = 0;
167 info.si_code = BUS_ADRALN;
168 info.si_addr = /* FIXME: Should dig out mna address */ (void *)0;
169 info.si_trapno = 0;
170 send_sig_info(SIGBUS, &info, current);
171}
172
173static unsigned long init_fsr = 0x0UL;
174static unsigned long init_fregs[32] __attribute__ ((aligned (8))) =
175 { ~0UL, ~0UL, ~0UL, ~0UL, ~0UL, ~0UL, ~0UL, ~0UL,
176 ~0UL, ~0UL, ~0UL, ~0UL, ~0UL, ~0UL, ~0UL, ~0UL,
177 ~0UL, ~0UL, ~0UL, ~0UL, ~0UL, ~0UL, ~0UL, ~0UL,
178 ~0UL, ~0UL, ~0UL, ~0UL, ~0UL, ~0UL, ~0UL, ~0UL };
179
180void do_fpd_trap(struct pt_regs *regs, unsigned long pc, unsigned long npc,
181 unsigned long psr)
182{
183 /* Sanity check... */
184 if(psr & PSR_PS)
185 die_if_kernel("Kernel gets FloatingPenguinUnit disabled trap", regs);
186
187 put_psr(get_psr() | PSR_EF); /* Allow FPU ops. */
188 regs->psr |= PSR_EF;
189#ifndef CONFIG_SMP
190 if(last_task_used_math == current)
191 return;
192 if(last_task_used_math) {
193 /* Other processes fpu state, save away */
194 struct task_struct *fptask = last_task_used_math;
195 fpsave(&fptask->thread.float_regs[0], &fptask->thread.fsr,
196 &fptask->thread.fpqueue[0], &fptask->thread.fpqdepth);
197 }
198 last_task_used_math = current;
199 if(used_math()) {
200 fpload(¤t->thread.float_regs[0], ¤t->thread.fsr);
201 } else {
202 /* Set initial sane state. */
203 fpload(&init_fregs[0], &init_fsr);
204 set_used_math();
205 }
206#else
207 if(!used_math()) {
208 fpload(&init_fregs[0], &init_fsr);
209 set_used_math();
210 } else {
211 fpload(¤t->thread.float_regs[0], ¤t->thread.fsr);
212 }
213 set_thread_flag(TIF_USEDFPU);
214#endif
215}
216
217static unsigned long fake_regs[32] __attribute__ ((aligned (8)));
218static unsigned long fake_fsr;
219static unsigned long fake_queue[32] __attribute__ ((aligned (8)));
220static unsigned long fake_depth;
221
222extern int do_mathemu(struct pt_regs *, struct task_struct *);
223
224void do_fpe_trap(struct pt_regs *regs, unsigned long pc, unsigned long npc,
225 unsigned long psr)
226{
227 static int calls;
228 siginfo_t info;
229 unsigned long fsr;
230 int ret = 0;
231#ifndef CONFIG_SMP
232 struct task_struct *fpt = last_task_used_math;
233#else
234 struct task_struct *fpt = current;
235#endif
236 put_psr(get_psr() | PSR_EF);
237 /* If nobody owns the fpu right now, just clear the
238 * error into our fake static buffer and hope it don't
239 * happen again. Thank you crashme...
240 */
241#ifndef CONFIG_SMP
242 if(!fpt) {
243#else
244 if (!test_tsk_thread_flag(fpt, TIF_USEDFPU)) {
245#endif
246 fpsave(&fake_regs[0], &fake_fsr, &fake_queue[0], &fake_depth);
247 regs->psr &= ~PSR_EF;
248 return;
249 }
250 fpsave(&fpt->thread.float_regs[0], &fpt->thread.fsr,
251 &fpt->thread.fpqueue[0], &fpt->thread.fpqdepth);
252#ifdef DEBUG_FPU
253 printk("Hmm, FP exception, fsr was %016lx\n", fpt->thread.fsr);
254#endif
255
256 switch ((fpt->thread.fsr & 0x1c000)) {
257 /* switch on the contents of the ftt [floating point trap type] field */
258#ifdef DEBUG_FPU
259 case (1 << 14):
260 printk("IEEE_754_exception\n");
261 break;
262#endif
263 case (2 << 14): /* unfinished_FPop (underflow & co) */
264 case (3 << 14): /* unimplemented_FPop (quad stuff, maybe sqrt) */
265 ret = do_mathemu(regs, fpt);
266 break;
267#ifdef DEBUG_FPU
268 case (4 << 14):
269 printk("sequence_error (OS bug...)\n");
270 break;
271 case (5 << 14):
272 printk("hardware_error (uhoh!)\n");
273 break;
274 case (6 << 14):
275 printk("invalid_fp_register (user error)\n");
276 break;
277#endif /* DEBUG_FPU */
278 }
279 /* If we successfully emulated the FPop, we pretend the trap never happened :-> */
280 if (ret) {
281 fpload(¤t->thread.float_regs[0], ¤t->thread.fsr);
282 return;
283 }
284 /* nope, better SIGFPE the offending process... */
285
286#ifdef CONFIG_SMP
287 clear_tsk_thread_flag(fpt, TIF_USEDFPU);
288#endif
289 if(psr & PSR_PS) {
290 /* The first fsr store/load we tried trapped,
291 * the second one will not (we hope).
292 */
293 printk("WARNING: FPU exception from kernel mode. at pc=%08lx\n",
294 regs->pc);
295 regs->pc = regs->npc;
296 regs->npc += 4;
297 calls++;
298 if(calls > 2)
299 die_if_kernel("Too many Penguin-FPU traps from kernel mode",
300 regs);
301 return;
302 }
303
304 fsr = fpt->thread.fsr;
305 info.si_signo = SIGFPE;
306 info.si_errno = 0;
307 info.si_addr = (void __user *)pc;
308 info.si_trapno = 0;
309 info.si_code = __SI_FAULT;
310 if ((fsr & 0x1c000) == (1 << 14)) {
311 if (fsr & 0x10)
312 info.si_code = FPE_FLTINV;
313 else if (fsr & 0x08)
314 info.si_code = FPE_FLTOVF;
315 else if (fsr & 0x04)
316 info.si_code = FPE_FLTUND;
317 else if (fsr & 0x02)
318 info.si_code = FPE_FLTDIV;
319 else if (fsr & 0x01)
320 info.si_code = FPE_FLTRES;
321 }
322 send_sig_info(SIGFPE, &info, fpt);
323#ifndef CONFIG_SMP
324 last_task_used_math = NULL;
325#endif
326 regs->psr &= ~PSR_EF;
327 if(calls > 0)
328 calls=0;
329}
330
331void handle_tag_overflow(struct pt_regs *regs, unsigned long pc, unsigned long npc,
332 unsigned long psr)
333{
334 siginfo_t info;
335
336 if(psr & PSR_PS)
337 die_if_kernel("Penguin overflow trap from kernel mode", regs);
338 info.si_signo = SIGEMT;
339 info.si_errno = 0;
340 info.si_code = EMT_TAGOVF;
341 info.si_addr = (void __user *)pc;
342 info.si_trapno = 0;
343 send_sig_info(SIGEMT, &info, current);
344}
345
346void handle_watchpoint(struct pt_regs *regs, unsigned long pc, unsigned long npc,
347 unsigned long psr)
348{
349#ifdef TRAP_DEBUG
350 printk("Watchpoint detected at PC %08lx NPC %08lx PSR %08lx\n",
351 pc, npc, psr);
352#endif
353 if(psr & PSR_PS)
354 panic("Tell me what a watchpoint trap is, and I'll then deal "
355 "with such a beast...");
356}
357
358void handle_reg_access(struct pt_regs *regs, unsigned long pc, unsigned long npc,
359 unsigned long psr)
360{
361 siginfo_t info;
362
363#ifdef TRAP_DEBUG
364 printk("Register Access Exception at PC %08lx NPC %08lx PSR %08lx\n",
365 pc, npc, psr);
366#endif
367 info.si_signo = SIGBUS;
368 info.si_errno = 0;
369 info.si_code = BUS_OBJERR;
370 info.si_addr = (void __user *)pc;
371 info.si_trapno = 0;
372 force_sig_info(SIGBUS, &info, current);
373}
374
375void handle_cp_disabled(struct pt_regs *regs, unsigned long pc, unsigned long npc,
376 unsigned long psr)
377{
378 siginfo_t info;
379
380 info.si_signo = SIGILL;
381 info.si_errno = 0;
382 info.si_code = ILL_COPROC;
383 info.si_addr = (void __user *)pc;
384 info.si_trapno = 0;
385 send_sig_info(SIGILL, &info, current);
386}
387
388void handle_cp_exception(struct pt_regs *regs, unsigned long pc, unsigned long npc,
389 unsigned long psr)
390{
391 siginfo_t info;
392
393#ifdef TRAP_DEBUG
394 printk("Co-Processor Exception at PC %08lx NPC %08lx PSR %08lx\n",
395 pc, npc, psr);
396#endif
397 info.si_signo = SIGILL;
398 info.si_errno = 0;
399 info.si_code = ILL_COPROC;
400 info.si_addr = (void __user *)pc;
401 info.si_trapno = 0;
402 send_sig_info(SIGILL, &info, current);
403}
404
405void handle_hw_divzero(struct pt_regs *regs, unsigned long pc, unsigned long npc,
406 unsigned long psr)
407{
408 siginfo_t info;
409
410 info.si_signo = SIGFPE;
411 info.si_errno = 0;
412 info.si_code = FPE_INTDIV;
413 info.si_addr = (void __user *)pc;
414 info.si_trapno = 0;
415 send_sig_info(SIGFPE, &info, current);
416}
417
418#ifdef CONFIG_DEBUG_BUGVERBOSE
419void do_BUG(const char *file, int line)
420{
421 // bust_spinlocks(1); XXX Not in our original BUG()
422 printk("kernel BUG at %s:%d!\n", file, line);
423}
424EXPORT_SYMBOL(do_BUG);
425#endif
426
427/* Since we have our mappings set up, on multiprocessors we can spin them
428 * up here so that timer interrupts work during initialization.
429 */
430
431void trap_init(void)
432{
433 extern void thread_info_offsets_are_bolixed_pete(void);
434
435 /* Force linker to barf if mismatched */
436 if (TI_UWINMASK != offsetof(struct thread_info, uwinmask) ||
437 TI_TASK != offsetof(struct thread_info, task) ||
438 TI_EXECDOMAIN != offsetof(struct thread_info, exec_domain) ||
439 TI_FLAGS != offsetof(struct thread_info, flags) ||
440 TI_CPU != offsetof(struct thread_info, cpu) ||
441 TI_PREEMPT != offsetof(struct thread_info, preempt_count) ||
442 TI_SOFTIRQ != offsetof(struct thread_info, softirq_count) ||
443 TI_HARDIRQ != offsetof(struct thread_info, hardirq_count) ||
444 TI_KSP != offsetof(struct thread_info, ksp) ||
445 TI_KPC != offsetof(struct thread_info, kpc) ||
446 TI_KPSR != offsetof(struct thread_info, kpsr) ||
447 TI_KWIM != offsetof(struct thread_info, kwim) ||
448 TI_REG_WINDOW != offsetof(struct thread_info, reg_window) ||
449 TI_RWIN_SPTRS != offsetof(struct thread_info, rwbuf_stkptrs) ||
450 TI_W_SAVED != offsetof(struct thread_info, w_saved))
451 thread_info_offsets_are_bolixed_pete();
452
453 /* Attach to the address space of init_task. */
454 atomic_inc(&init_mm.mm_count);
455 current->active_mm = &init_mm;
456
457 /* NOTE: Other cpus have this done as they are started
458 * up on SMP.
459 */
460}
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * arch/sparc/kernel/traps.c
4 *
5 * Copyright 1995, 2008 David S. Miller (davem@davemloft.net)
6 * Copyright 2000 Jakub Jelinek (jakub@redhat.com)
7 */
8
9/*
10 * I hate traps on the sparc, grrr...
11 */
12
13#include <linux/cpu.h>
14#include <linux/sched/mm.h>
15#include <linux/sched/debug.h>
16#include <linux/mm_types.h>
17#include <linux/kernel.h>
18#include <linux/signal.h>
19#include <linux/smp.h>
20#include <linux/kdebug.h>
21#include <linux/export.h>
22#include <linux/pgtable.h>
23
24#include <asm/delay.h>
25#include <asm/ptrace.h>
26#include <asm/oplib.h>
27#include <asm/page.h>
28#include <asm/unistd.h>
29#include <asm/traps.h>
30
31#include "entry.h"
32#include "kernel.h"
33
34/* #define TRAP_DEBUG */
35
36static void instruction_dump(unsigned long *pc)
37{
38 int i;
39
40 if((((unsigned long) pc) & 3))
41 return;
42
43 for(i = -3; i < 6; i++)
44 printk("%c%08lx%c",i?' ':'<',pc[i],i?' ':'>');
45 printk("\n");
46}
47
48#define __SAVE __asm__ __volatile__("save %sp, -0x40, %sp\n\t")
49#define __RESTORE __asm__ __volatile__("restore %g0, %g0, %g0\n\t")
50
51void __noreturn die_if_kernel(char *str, struct pt_regs *regs)
52{
53 static int die_counter;
54 int count = 0;
55
56 /* Amuse the user. */
57 printk(
58" \\|/ ____ \\|/\n"
59" \"@'/ ,. \\`@\"\n"
60" /_| \\__/ |_\\\n"
61" \\__U_/\n");
62
63 printk("%s(%d): %s [#%d]\n", current->comm, task_pid_nr(current), str, ++die_counter);
64 show_regs(regs);
65 add_taint(TAINT_DIE, LOCKDEP_NOW_UNRELIABLE);
66
67 __SAVE; __SAVE; __SAVE; __SAVE;
68 __SAVE; __SAVE; __SAVE; __SAVE;
69 __RESTORE; __RESTORE; __RESTORE; __RESTORE;
70 __RESTORE; __RESTORE; __RESTORE; __RESTORE;
71
72 {
73 struct reg_window32 *rw = (struct reg_window32 *)regs->u_regs[UREG_FP];
74
75 /* Stop the back trace when we hit userland or we
76 * find some badly aligned kernel stack. Set an upper
77 * bound in case our stack is trashed and we loop.
78 */
79 while(rw &&
80 count++ < 30 &&
81 (((unsigned long) rw) >= PAGE_OFFSET) &&
82 !(((unsigned long) rw) & 0x7)) {
83 printk("Caller[%08lx]: %pS\n", rw->ins[7],
84 (void *) rw->ins[7]);
85 rw = (struct reg_window32 *)rw->ins[6];
86 }
87 }
88 printk("Instruction DUMP:");
89 instruction_dump ((unsigned long *) regs->pc);
90 make_task_dead((regs->psr & PSR_PS) ? SIGKILL : SIGSEGV);
91}
92
93void do_hw_interrupt(struct pt_regs *regs, unsigned long type)
94{
95 if(type < 0x80) {
96 /* Sun OS's puke from bad traps, Linux survives! */
97 printk("Unimplemented Sparc TRAP, type = %02lx\n", type);
98 die_if_kernel("Whee... Hello Mr. Penguin", regs);
99 }
100
101 if(regs->psr & PSR_PS)
102 die_if_kernel("Kernel bad trap", regs);
103
104 force_sig_fault_trapno(SIGILL, ILL_ILLTRP,
105 (void __user *)regs->pc, type - 0x80);
106}
107
108void do_illegal_instruction(struct pt_regs *regs, unsigned long pc, unsigned long npc,
109 unsigned long psr)
110{
111 if(psr & PSR_PS)
112 die_if_kernel("Kernel illegal instruction", regs);
113#ifdef TRAP_DEBUG
114 printk("Ill instr. at pc=%08lx instruction is %08lx\n",
115 regs->pc, *(unsigned long *)regs->pc);
116#endif
117
118 send_sig_fault(SIGILL, ILL_ILLOPC, (void __user *)pc, current);
119}
120
121void do_priv_instruction(struct pt_regs *regs, unsigned long pc, unsigned long npc,
122 unsigned long psr)
123{
124 if(psr & PSR_PS)
125 die_if_kernel("Penguin instruction from Penguin mode??!?!", regs);
126 send_sig_fault(SIGILL, ILL_PRVOPC, (void __user *)pc, current);
127}
128
129/* XXX User may want to be allowed to do this. XXX */
130
131void do_memaccess_unaligned(struct pt_regs *regs, unsigned long pc, unsigned long npc,
132 unsigned long psr)
133{
134 if(regs->psr & PSR_PS) {
135 printk("KERNEL MNA at pc %08lx npc %08lx called by %08lx\n", pc, npc,
136 regs->u_regs[UREG_RETPC]);
137 die_if_kernel("BOGUS", regs);
138 /* die_if_kernel("Kernel MNA access", regs); */
139 }
140#if 0
141 show_regs (regs);
142 instruction_dump ((unsigned long *) regs->pc);
143 printk ("do_MNA!\n");
144#endif
145 send_sig_fault(SIGBUS, BUS_ADRALN,
146 /* FIXME: Should dig out mna address */ (void *)0,
147 current);
148}
149
150static unsigned long init_fsr = 0x0UL;
151static unsigned long init_fregs[32] __attribute__ ((aligned (8))) =
152 { ~0UL, ~0UL, ~0UL, ~0UL, ~0UL, ~0UL, ~0UL, ~0UL,
153 ~0UL, ~0UL, ~0UL, ~0UL, ~0UL, ~0UL, ~0UL, ~0UL,
154 ~0UL, ~0UL, ~0UL, ~0UL, ~0UL, ~0UL, ~0UL, ~0UL,
155 ~0UL, ~0UL, ~0UL, ~0UL, ~0UL, ~0UL, ~0UL, ~0UL };
156
157void do_fpd_trap(struct pt_regs *regs, unsigned long pc, unsigned long npc,
158 unsigned long psr)
159{
160 /* Sanity check... */
161 if(psr & PSR_PS)
162 die_if_kernel("Kernel gets FloatingPenguinUnit disabled trap", regs);
163
164 put_psr(get_psr() | PSR_EF); /* Allow FPU ops. */
165 regs->psr |= PSR_EF;
166#ifndef CONFIG_SMP
167 if(last_task_used_math == current)
168 return;
169 if(last_task_used_math) {
170 /* Other processes fpu state, save away */
171 struct task_struct *fptask = last_task_used_math;
172 fpsave(&fptask->thread.float_regs[0], &fptask->thread.fsr,
173 &fptask->thread.fpqueue[0], &fptask->thread.fpqdepth);
174 }
175 last_task_used_math = current;
176 if(used_math()) {
177 fpload(¤t->thread.float_regs[0], ¤t->thread.fsr);
178 } else {
179 /* Set initial sane state. */
180 fpload(&init_fregs[0], &init_fsr);
181 set_used_math();
182 }
183#else
184 if(!used_math()) {
185 fpload(&init_fregs[0], &init_fsr);
186 set_used_math();
187 } else {
188 fpload(¤t->thread.float_regs[0], ¤t->thread.fsr);
189 }
190 set_thread_flag(TIF_USEDFPU);
191#endif
192}
193
194static unsigned long fake_regs[32] __attribute__ ((aligned (8)));
195static unsigned long fake_fsr;
196static unsigned long fake_queue[32] __attribute__ ((aligned (8)));
197static unsigned long fake_depth;
198
199void do_fpe_trap(struct pt_regs *regs, unsigned long pc, unsigned long npc,
200 unsigned long psr)
201{
202 static int calls;
203 unsigned long fsr;
204 int ret = 0;
205 int code;
206#ifndef CONFIG_SMP
207 struct task_struct *fpt = last_task_used_math;
208#else
209 struct task_struct *fpt = current;
210#endif
211 put_psr(get_psr() | PSR_EF);
212 /* If nobody owns the fpu right now, just clear the
213 * error into our fake static buffer and hope it don't
214 * happen again. Thank you crashme...
215 */
216#ifndef CONFIG_SMP
217 if(!fpt) {
218#else
219 if (!test_tsk_thread_flag(fpt, TIF_USEDFPU)) {
220#endif
221 fpsave(&fake_regs[0], &fake_fsr, &fake_queue[0], &fake_depth);
222 regs->psr &= ~PSR_EF;
223 return;
224 }
225 fpsave(&fpt->thread.float_regs[0], &fpt->thread.fsr,
226 &fpt->thread.fpqueue[0], &fpt->thread.fpqdepth);
227#ifdef DEBUG_FPU
228 printk("Hmm, FP exception, fsr was %016lx\n", fpt->thread.fsr);
229#endif
230
231 switch ((fpt->thread.fsr & 0x1c000)) {
232 /* switch on the contents of the ftt [floating point trap type] field */
233#ifdef DEBUG_FPU
234 case (1 << 14):
235 printk("IEEE_754_exception\n");
236 break;
237#endif
238 case (2 << 14): /* unfinished_FPop (underflow & co) */
239 case (3 << 14): /* unimplemented_FPop (quad stuff, maybe sqrt) */
240 ret = do_mathemu(regs, fpt);
241 break;
242#ifdef DEBUG_FPU
243 case (4 << 14):
244 printk("sequence_error (OS bug...)\n");
245 break;
246 case (5 << 14):
247 printk("hardware_error (uhoh!)\n");
248 break;
249 case (6 << 14):
250 printk("invalid_fp_register (user error)\n");
251 break;
252#endif /* DEBUG_FPU */
253 }
254 /* If we successfully emulated the FPop, we pretend the trap never happened :-> */
255 if (ret) {
256 fpload(¤t->thread.float_regs[0], ¤t->thread.fsr);
257 return;
258 }
259 /* nope, better SIGFPE the offending process... */
260
261#ifdef CONFIG_SMP
262 clear_tsk_thread_flag(fpt, TIF_USEDFPU);
263#endif
264 if(psr & PSR_PS) {
265 /* The first fsr store/load we tried trapped,
266 * the second one will not (we hope).
267 */
268 printk("WARNING: FPU exception from kernel mode. at pc=%08lx\n",
269 regs->pc);
270 regs->pc = regs->npc;
271 regs->npc += 4;
272 calls++;
273 if(calls > 2)
274 die_if_kernel("Too many Penguin-FPU traps from kernel mode",
275 regs);
276 return;
277 }
278
279 fsr = fpt->thread.fsr;
280 code = FPE_FLTUNK;
281 if ((fsr & 0x1c000) == (1 << 14)) {
282 if (fsr & 0x10)
283 code = FPE_FLTINV;
284 else if (fsr & 0x08)
285 code = FPE_FLTOVF;
286 else if (fsr & 0x04)
287 code = FPE_FLTUND;
288 else if (fsr & 0x02)
289 code = FPE_FLTDIV;
290 else if (fsr & 0x01)
291 code = FPE_FLTRES;
292 }
293 send_sig_fault(SIGFPE, code, (void __user *)pc, fpt);
294#ifndef CONFIG_SMP
295 last_task_used_math = NULL;
296#endif
297 regs->psr &= ~PSR_EF;
298 if(calls > 0)
299 calls=0;
300}
301
302void handle_tag_overflow(struct pt_regs *regs, unsigned long pc, unsigned long npc,
303 unsigned long psr)
304{
305 if(psr & PSR_PS)
306 die_if_kernel("Penguin overflow trap from kernel mode", regs);
307 send_sig_fault(SIGEMT, EMT_TAGOVF, (void __user *)pc, current);
308}
309
310void handle_watchpoint(struct pt_regs *regs, unsigned long pc, unsigned long npc,
311 unsigned long psr)
312{
313#ifdef TRAP_DEBUG
314 printk("Watchpoint detected at PC %08lx NPC %08lx PSR %08lx\n",
315 pc, npc, psr);
316#endif
317 if(psr & PSR_PS)
318 panic("Tell me what a watchpoint trap is, and I'll then deal "
319 "with such a beast...");
320}
321
322void handle_reg_access(struct pt_regs *regs, unsigned long pc, unsigned long npc,
323 unsigned long psr)
324{
325#ifdef TRAP_DEBUG
326 printk("Register Access Exception at PC %08lx NPC %08lx PSR %08lx\n",
327 pc, npc, psr);
328#endif
329 force_sig_fault(SIGBUS, BUS_OBJERR, (void __user *)pc);
330}
331
332void handle_cp_disabled(struct pt_regs *regs, unsigned long pc, unsigned long npc,
333 unsigned long psr)
334{
335 send_sig_fault(SIGILL, ILL_COPROC, (void __user *)pc, current);
336}
337
338void handle_cp_exception(struct pt_regs *regs, unsigned long pc, unsigned long npc,
339 unsigned long psr)
340{
341#ifdef TRAP_DEBUG
342 printk("Co-Processor Exception at PC %08lx NPC %08lx PSR %08lx\n",
343 pc, npc, psr);
344#endif
345 send_sig_fault(SIGILL, ILL_COPROC, (void __user *)pc, current);
346}
347
348void handle_hw_divzero(struct pt_regs *regs, unsigned long pc, unsigned long npc,
349 unsigned long psr)
350{
351 send_sig_fault(SIGFPE, FPE_INTDIV, (void __user *)pc, current);
352}
353
354#ifdef CONFIG_DEBUG_BUGVERBOSE
355void do_BUG(const char *file, int line)
356{
357 // bust_spinlocks(1); XXX Not in our original BUG()
358 printk("kernel BUG at %s:%d!\n", file, line);
359}
360EXPORT_SYMBOL(do_BUG);
361#endif
362
363/* Since we have our mappings set up, on multiprocessors we can spin them
364 * up here so that timer interrupts work during initialization.
365 */
366
367void trap_init(void)
368{
369 extern void thread_info_offsets_are_bolixed_pete(void);
370
371 /* Force linker to barf if mismatched */
372 if (TI_UWINMASK != offsetof(struct thread_info, uwinmask) ||
373 TI_TASK != offsetof(struct thread_info, task) ||
374 TI_FLAGS != offsetof(struct thread_info, flags) ||
375 TI_CPU != offsetof(struct thread_info, cpu) ||
376 TI_PREEMPT != offsetof(struct thread_info, preempt_count) ||
377 TI_SOFTIRQ != offsetof(struct thread_info, softirq_count) ||
378 TI_HARDIRQ != offsetof(struct thread_info, hardirq_count) ||
379 TI_KSP != offsetof(struct thread_info, ksp) ||
380 TI_KPC != offsetof(struct thread_info, kpc) ||
381 TI_KPSR != offsetof(struct thread_info, kpsr) ||
382 TI_KWIM != offsetof(struct thread_info, kwim) ||
383 TI_REG_WINDOW != offsetof(struct thread_info, reg_window) ||
384 TI_RWIN_SPTRS != offsetof(struct thread_info, rwbuf_stkptrs) ||
385 TI_W_SAVED != offsetof(struct thread_info, w_saved))
386 thread_info_offsets_are_bolixed_pete();
387
388 /* Attach to the address space of init_task. */
389 mmgrab(&init_mm);
390 current->active_mm = &init_mm;
391
392 /* NOTE: Other cpus have this done as they are started
393 * up on SMP.
394 */
395}