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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
18#include <asm/delay.h>
19#include <asm/system.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 if (!do_user_muldiv (regs, pc))
124 return;
125
126 info.si_signo = SIGILL;
127 info.si_errno = 0;
128 info.si_code = ILL_ILLOPC;
129 info.si_addr = (void __user *)pc;
130 info.si_trapno = 0;
131 send_sig_info(SIGILL, &info, current);
132}
133
134void do_priv_instruction(struct pt_regs *regs, unsigned long pc, unsigned long npc,
135 unsigned long psr)
136{
137 siginfo_t info;
138
139 if(psr & PSR_PS)
140 die_if_kernel("Penguin instruction from Penguin mode??!?!", regs);
141 info.si_signo = SIGILL;
142 info.si_errno = 0;
143 info.si_code = ILL_PRVOPC;
144 info.si_addr = (void __user *)pc;
145 info.si_trapno = 0;
146 send_sig_info(SIGILL, &info, current);
147}
148
149/* XXX User may want to be allowed to do this. XXX */
150
151void do_memaccess_unaligned(struct pt_regs *regs, unsigned long pc, unsigned long npc,
152 unsigned long psr)
153{
154 siginfo_t info;
155
156 if(regs->psr & PSR_PS) {
157 printk("KERNEL MNA at pc %08lx npc %08lx called by %08lx\n", pc, npc,
158 regs->u_regs[UREG_RETPC]);
159 die_if_kernel("BOGUS", regs);
160 /* die_if_kernel("Kernel MNA access", regs); */
161 }
162#if 0
163 show_regs (regs);
164 instruction_dump ((unsigned long *) regs->pc);
165 printk ("do_MNA!\n");
166#endif
167 info.si_signo = SIGBUS;
168 info.si_errno = 0;
169 info.si_code = BUS_ADRALN;
170 info.si_addr = /* FIXME: Should dig out mna address */ (void *)0;
171 info.si_trapno = 0;
172 send_sig_info(SIGBUS, &info, current);
173}
174
175static unsigned long init_fsr = 0x0UL;
176static unsigned long init_fregs[32] __attribute__ ((aligned (8))) =
177 { ~0UL, ~0UL, ~0UL, ~0UL, ~0UL, ~0UL, ~0UL, ~0UL,
178 ~0UL, ~0UL, ~0UL, ~0UL, ~0UL, ~0UL, ~0UL, ~0UL,
179 ~0UL, ~0UL, ~0UL, ~0UL, ~0UL, ~0UL, ~0UL, ~0UL,
180 ~0UL, ~0UL, ~0UL, ~0UL, ~0UL, ~0UL, ~0UL, ~0UL };
181
182void do_fpd_trap(struct pt_regs *regs, unsigned long pc, unsigned long npc,
183 unsigned long psr)
184{
185 /* Sanity check... */
186 if(psr & PSR_PS)
187 die_if_kernel("Kernel gets FloatingPenguinUnit disabled trap", regs);
188
189 put_psr(get_psr() | PSR_EF); /* Allow FPU ops. */
190 regs->psr |= PSR_EF;
191#ifndef CONFIG_SMP
192 if(last_task_used_math == current)
193 return;
194 if(last_task_used_math) {
195 /* Other processes fpu state, save away */
196 struct task_struct *fptask = last_task_used_math;
197 fpsave(&fptask->thread.float_regs[0], &fptask->thread.fsr,
198 &fptask->thread.fpqueue[0], &fptask->thread.fpqdepth);
199 }
200 last_task_used_math = current;
201 if(used_math()) {
202 fpload(¤t->thread.float_regs[0], ¤t->thread.fsr);
203 } else {
204 /* Set initial sane state. */
205 fpload(&init_fregs[0], &init_fsr);
206 set_used_math();
207 }
208#else
209 if(!used_math()) {
210 fpload(&init_fregs[0], &init_fsr);
211 set_used_math();
212 } else {
213 fpload(¤t->thread.float_regs[0], ¤t->thread.fsr);
214 }
215 set_thread_flag(TIF_USEDFPU);
216#endif
217}
218
219static unsigned long fake_regs[32] __attribute__ ((aligned (8)));
220static unsigned long fake_fsr;
221static unsigned long fake_queue[32] __attribute__ ((aligned (8)));
222static unsigned long fake_depth;
223
224extern int do_mathemu(struct pt_regs *, struct task_struct *);
225
226void do_fpe_trap(struct pt_regs *regs, unsigned long pc, unsigned long npc,
227 unsigned long psr)
228{
229 static int calls;
230 siginfo_t info;
231 unsigned long fsr;
232 int ret = 0;
233#ifndef CONFIG_SMP
234 struct task_struct *fpt = last_task_used_math;
235#else
236 struct task_struct *fpt = current;
237#endif
238 put_psr(get_psr() | PSR_EF);
239 /* If nobody owns the fpu right now, just clear the
240 * error into our fake static buffer and hope it don't
241 * happen again. Thank you crashme...
242 */
243#ifndef CONFIG_SMP
244 if(!fpt) {
245#else
246 if (!test_tsk_thread_flag(fpt, TIF_USEDFPU)) {
247#endif
248 fpsave(&fake_regs[0], &fake_fsr, &fake_queue[0], &fake_depth);
249 regs->psr &= ~PSR_EF;
250 return;
251 }
252 fpsave(&fpt->thread.float_regs[0], &fpt->thread.fsr,
253 &fpt->thread.fpqueue[0], &fpt->thread.fpqdepth);
254#ifdef DEBUG_FPU
255 printk("Hmm, FP exception, fsr was %016lx\n", fpt->thread.fsr);
256#endif
257
258 switch ((fpt->thread.fsr & 0x1c000)) {
259 /* switch on the contents of the ftt [floating point trap type] field */
260#ifdef DEBUG_FPU
261 case (1 << 14):
262 printk("IEEE_754_exception\n");
263 break;
264#endif
265 case (2 << 14): /* unfinished_FPop (underflow & co) */
266 case (3 << 14): /* unimplemented_FPop (quad stuff, maybe sqrt) */
267 ret = do_mathemu(regs, fpt);
268 break;
269#ifdef DEBUG_FPU
270 case (4 << 14):
271 printk("sequence_error (OS bug...)\n");
272 break;
273 case (5 << 14):
274 printk("hardware_error (uhoh!)\n");
275 break;
276 case (6 << 14):
277 printk("invalid_fp_register (user error)\n");
278 break;
279#endif /* DEBUG_FPU */
280 }
281 /* If we successfully emulated the FPop, we pretend the trap never happened :-> */
282 if (ret) {
283 fpload(¤t->thread.float_regs[0], ¤t->thread.fsr);
284 return;
285 }
286 /* nope, better SIGFPE the offending process... */
287
288#ifdef CONFIG_SMP
289 clear_tsk_thread_flag(fpt, TIF_USEDFPU);
290#endif
291 if(psr & PSR_PS) {
292 /* The first fsr store/load we tried trapped,
293 * the second one will not (we hope).
294 */
295 printk("WARNING: FPU exception from kernel mode. at pc=%08lx\n",
296 regs->pc);
297 regs->pc = regs->npc;
298 regs->npc += 4;
299 calls++;
300 if(calls > 2)
301 die_if_kernel("Too many Penguin-FPU traps from kernel mode",
302 regs);
303 return;
304 }
305
306 fsr = fpt->thread.fsr;
307 info.si_signo = SIGFPE;
308 info.si_errno = 0;
309 info.si_addr = (void __user *)pc;
310 info.si_trapno = 0;
311 info.si_code = __SI_FAULT;
312 if ((fsr & 0x1c000) == (1 << 14)) {
313 if (fsr & 0x10)
314 info.si_code = FPE_FLTINV;
315 else if (fsr & 0x08)
316 info.si_code = FPE_FLTOVF;
317 else if (fsr & 0x04)
318 info.si_code = FPE_FLTUND;
319 else if (fsr & 0x02)
320 info.si_code = FPE_FLTDIV;
321 else if (fsr & 0x01)
322 info.si_code = FPE_FLTRES;
323 }
324 send_sig_info(SIGFPE, &info, fpt);
325#ifndef CONFIG_SMP
326 last_task_used_math = NULL;
327#endif
328 regs->psr &= ~PSR_EF;
329 if(calls > 0)
330 calls=0;
331}
332
333void handle_tag_overflow(struct pt_regs *regs, unsigned long pc, unsigned long npc,
334 unsigned long psr)
335{
336 siginfo_t info;
337
338 if(psr & PSR_PS)
339 die_if_kernel("Penguin overflow trap from kernel mode", regs);
340 info.si_signo = SIGEMT;
341 info.si_errno = 0;
342 info.si_code = EMT_TAGOVF;
343 info.si_addr = (void __user *)pc;
344 info.si_trapno = 0;
345 send_sig_info(SIGEMT, &info, current);
346}
347
348void handle_watchpoint(struct pt_regs *regs, unsigned long pc, unsigned long npc,
349 unsigned long psr)
350{
351#ifdef TRAP_DEBUG
352 printk("Watchpoint detected at PC %08lx NPC %08lx PSR %08lx\n",
353 pc, npc, psr);
354#endif
355 if(psr & PSR_PS)
356 panic("Tell me what a watchpoint trap is, and I'll then deal "
357 "with such a beast...");
358}
359
360void handle_reg_access(struct pt_regs *regs, unsigned long pc, unsigned long npc,
361 unsigned long psr)
362{
363 siginfo_t info;
364
365#ifdef TRAP_DEBUG
366 printk("Register Access Exception at PC %08lx NPC %08lx PSR %08lx\n",
367 pc, npc, psr);
368#endif
369 info.si_signo = SIGBUS;
370 info.si_errno = 0;
371 info.si_code = BUS_OBJERR;
372 info.si_addr = (void __user *)pc;
373 info.si_trapno = 0;
374 force_sig_info(SIGBUS, &info, current);
375}
376
377void handle_cp_disabled(struct pt_regs *regs, unsigned long pc, unsigned long npc,
378 unsigned long psr)
379{
380 siginfo_t info;
381
382 info.si_signo = SIGILL;
383 info.si_errno = 0;
384 info.si_code = ILL_COPROC;
385 info.si_addr = (void __user *)pc;
386 info.si_trapno = 0;
387 send_sig_info(SIGILL, &info, current);
388}
389
390void handle_cp_exception(struct pt_regs *regs, unsigned long pc, unsigned long npc,
391 unsigned long psr)
392{
393 siginfo_t info;
394
395#ifdef TRAP_DEBUG
396 printk("Co-Processor Exception at PC %08lx NPC %08lx PSR %08lx\n",
397 pc, npc, psr);
398#endif
399 info.si_signo = SIGILL;
400 info.si_errno = 0;
401 info.si_code = ILL_COPROC;
402 info.si_addr = (void __user *)pc;
403 info.si_trapno = 0;
404 send_sig_info(SIGILL, &info, current);
405}
406
407void handle_hw_divzero(struct pt_regs *regs, unsigned long pc, unsigned long npc,
408 unsigned long psr)
409{
410 siginfo_t info;
411
412 info.si_signo = SIGFPE;
413 info.si_errno = 0;
414 info.si_code = FPE_INTDIV;
415 info.si_addr = (void __user *)pc;
416 info.si_trapno = 0;
417 send_sig_info(SIGFPE, &info, current);
418}
419
420#ifdef CONFIG_DEBUG_BUGVERBOSE
421void do_BUG(const char *file, int line)
422{
423 // bust_spinlocks(1); XXX Not in our original BUG()
424 printk("kernel BUG at %s:%d!\n", file, line);
425}
426EXPORT_SYMBOL(do_BUG);
427#endif
428
429/* Since we have our mappings set up, on multiprocessors we can spin them
430 * up here so that timer interrupts work during initialization.
431 */
432
433void trap_init(void)
434{
435 extern void thread_info_offsets_are_bolixed_pete(void);
436
437 /* Force linker to barf if mismatched */
438 if (TI_UWINMASK != offsetof(struct thread_info, uwinmask) ||
439 TI_TASK != offsetof(struct thread_info, task) ||
440 TI_EXECDOMAIN != offsetof(struct thread_info, exec_domain) ||
441 TI_FLAGS != offsetof(struct thread_info, flags) ||
442 TI_CPU != offsetof(struct thread_info, cpu) ||
443 TI_PREEMPT != offsetof(struct thread_info, preempt_count) ||
444 TI_SOFTIRQ != offsetof(struct thread_info, softirq_count) ||
445 TI_HARDIRQ != offsetof(struct thread_info, hardirq_count) ||
446 TI_KSP != offsetof(struct thread_info, ksp) ||
447 TI_KPC != offsetof(struct thread_info, kpc) ||
448 TI_KPSR != offsetof(struct thread_info, kpsr) ||
449 TI_KWIM != offsetof(struct thread_info, kwim) ||
450 TI_REG_WINDOW != offsetof(struct thread_info, reg_window) ||
451 TI_RWIN_SPTRS != offsetof(struct thread_info, rwbuf_stkptrs) ||
452 TI_W_SAVED != offsetof(struct thread_info, w_saved))
453 thread_info_offsets_are_bolixed_pete();
454
455 /* Attach to the address space of init_task. */
456 atomic_inc(&init_mm.mm_count);
457 current->active_mm = &init_mm;
458
459 /* NOTE: Other cpus have this done as they are started
460 * up on SMP.
461 */
462}
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/sched/mm.h>
14#include <linux/sched/debug.h>
15#include <linux/mm_types.h>
16#include <linux/kernel.h>
17#include <linux/signal.h>
18#include <linux/smp.h>
19#include <linux/kdebug.h>
20#include <linux/export.h>
21#include <linux/pgtable.h>
22
23#include <asm/delay.h>
24#include <asm/ptrace.h>
25#include <asm/oplib.h>
26#include <asm/page.h>
27#include <asm/unistd.h>
28#include <asm/traps.h>
29
30#include "entry.h"
31#include "kernel.h"
32
33/* #define TRAP_DEBUG */
34
35static void instruction_dump(unsigned long *pc)
36{
37 int i;
38
39 if((((unsigned long) pc) & 3))
40 return;
41
42 for(i = -3; i < 6; i++)
43 printk("%c%08lx%c",i?' ':'<',pc[i],i?' ':'>');
44 printk("\n");
45}
46
47#define __SAVE __asm__ __volatile__("save %sp, -0x40, %sp\n\t")
48#define __RESTORE __asm__ __volatile__("restore %g0, %g0, %g0\n\t")
49
50void __noreturn die_if_kernel(char *str, struct pt_regs *regs)
51{
52 static int die_counter;
53 int count = 0;
54
55 /* Amuse the user. */
56 printk(
57" \\|/ ____ \\|/\n"
58" \"@'/ ,. \\`@\"\n"
59" /_| \\__/ |_\\\n"
60" \\__U_/\n");
61
62 printk("%s(%d): %s [#%d]\n", current->comm, task_pid_nr(current), str, ++die_counter);
63 show_regs(regs);
64 add_taint(TAINT_DIE, LOCKDEP_NOW_UNRELIABLE);
65
66 __SAVE; __SAVE; __SAVE; __SAVE;
67 __SAVE; __SAVE; __SAVE; __SAVE;
68 __RESTORE; __RESTORE; __RESTORE; __RESTORE;
69 __RESTORE; __RESTORE; __RESTORE; __RESTORE;
70
71 {
72 struct reg_window32 *rw = (struct reg_window32 *)regs->u_regs[UREG_FP];
73
74 /* Stop the back trace when we hit userland or we
75 * find some badly aligned kernel stack. Set an upper
76 * bound in case our stack is trashed and we loop.
77 */
78 while(rw &&
79 count++ < 30 &&
80 (((unsigned long) rw) >= PAGE_OFFSET) &&
81 !(((unsigned long) rw) & 0x7)) {
82 printk("Caller[%08lx]: %pS\n", rw->ins[7],
83 (void *) rw->ins[7]);
84 rw = (struct reg_window32 *)rw->ins[6];
85 }
86 }
87 printk("Instruction DUMP:");
88 instruction_dump ((unsigned long *) regs->pc);
89 make_task_dead((regs->psr & PSR_PS) ? SIGKILL : SIGSEGV);
90}
91
92void do_hw_interrupt(struct pt_regs *regs, unsigned long type)
93{
94 if(type < 0x80) {
95 /* Sun OS's puke from bad traps, Linux survives! */
96 printk("Unimplemented Sparc TRAP, type = %02lx\n", type);
97 die_if_kernel("Whee... Hello Mr. Penguin", regs);
98 }
99
100 if(regs->psr & PSR_PS)
101 die_if_kernel("Kernel bad trap", regs);
102
103 force_sig_fault_trapno(SIGILL, ILL_ILLTRP,
104 (void __user *)regs->pc, type - 0x80);
105}
106
107void do_illegal_instruction(struct pt_regs *regs, unsigned long pc, unsigned long npc,
108 unsigned long psr)
109{
110 if(psr & PSR_PS)
111 die_if_kernel("Kernel illegal instruction", regs);
112#ifdef TRAP_DEBUG
113 printk("Ill instr. at pc=%08lx instruction is %08lx\n",
114 regs->pc, *(unsigned long *)regs->pc);
115#endif
116
117 send_sig_fault(SIGILL, ILL_ILLOPC, (void __user *)pc, current);
118}
119
120void do_priv_instruction(struct pt_regs *regs, unsigned long pc, unsigned long npc,
121 unsigned long psr)
122{
123 if(psr & PSR_PS)
124 die_if_kernel("Penguin instruction from Penguin mode??!?!", regs);
125 send_sig_fault(SIGILL, ILL_PRVOPC, (void __user *)pc, current);
126}
127
128/* XXX User may want to be allowed to do this. XXX */
129
130void do_memaccess_unaligned(struct pt_regs *regs, unsigned long pc, unsigned long npc,
131 unsigned long psr)
132{
133 if(regs->psr & PSR_PS) {
134 printk("KERNEL MNA at pc %08lx npc %08lx called by %08lx\n", pc, npc,
135 regs->u_regs[UREG_RETPC]);
136 die_if_kernel("BOGUS", regs);
137 /* die_if_kernel("Kernel MNA access", regs); */
138 }
139#if 0
140 show_regs (regs);
141 instruction_dump ((unsigned long *) regs->pc);
142 printk ("do_MNA!\n");
143#endif
144 send_sig_fault(SIGBUS, BUS_ADRALN,
145 /* FIXME: Should dig out mna address */ (void *)0,
146 current);
147}
148
149static unsigned long init_fsr = 0x0UL;
150static unsigned long init_fregs[32] __attribute__ ((aligned (8))) =
151 { ~0UL, ~0UL, ~0UL, ~0UL, ~0UL, ~0UL, ~0UL, ~0UL,
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
156void do_fpd_trap(struct pt_regs *regs, unsigned long pc, unsigned long npc,
157 unsigned long psr)
158{
159 /* Sanity check... */
160 if(psr & PSR_PS)
161 die_if_kernel("Kernel gets FloatingPenguinUnit disabled trap", regs);
162
163 put_psr(get_psr() | PSR_EF); /* Allow FPU ops. */
164 regs->psr |= PSR_EF;
165#ifndef CONFIG_SMP
166 if(last_task_used_math == current)
167 return;
168 if(last_task_used_math) {
169 /* Other processes fpu state, save away */
170 struct task_struct *fptask = last_task_used_math;
171 fpsave(&fptask->thread.float_regs[0], &fptask->thread.fsr,
172 &fptask->thread.fpqueue[0], &fptask->thread.fpqdepth);
173 }
174 last_task_used_math = current;
175 if(used_math()) {
176 fpload(¤t->thread.float_regs[0], ¤t->thread.fsr);
177 } else {
178 /* Set initial sane state. */
179 fpload(&init_fregs[0], &init_fsr);
180 set_used_math();
181 }
182#else
183 if(!used_math()) {
184 fpload(&init_fregs[0], &init_fsr);
185 set_used_math();
186 } else {
187 fpload(¤t->thread.float_regs[0], ¤t->thread.fsr);
188 }
189 set_thread_flag(TIF_USEDFPU);
190#endif
191}
192
193static unsigned long fake_regs[32] __attribute__ ((aligned (8)));
194static unsigned long fake_fsr;
195static unsigned long fake_queue[32] __attribute__ ((aligned (8)));
196static unsigned long fake_depth;
197
198void do_fpe_trap(struct pt_regs *regs, unsigned long pc, unsigned long npc,
199 unsigned long psr)
200{
201 static int calls;
202 unsigned long fsr;
203 int ret = 0;
204 int code;
205#ifndef CONFIG_SMP
206 struct task_struct *fpt = last_task_used_math;
207#else
208 struct task_struct *fpt = current;
209#endif
210 put_psr(get_psr() | PSR_EF);
211 /* If nobody owns the fpu right now, just clear the
212 * error into our fake static buffer and hope it don't
213 * happen again. Thank you crashme...
214 */
215#ifndef CONFIG_SMP
216 if(!fpt) {
217#else
218 if (!test_tsk_thread_flag(fpt, TIF_USEDFPU)) {
219#endif
220 fpsave(&fake_regs[0], &fake_fsr, &fake_queue[0], &fake_depth);
221 regs->psr &= ~PSR_EF;
222 return;
223 }
224 fpsave(&fpt->thread.float_regs[0], &fpt->thread.fsr,
225 &fpt->thread.fpqueue[0], &fpt->thread.fpqdepth);
226#ifdef DEBUG_FPU
227 printk("Hmm, FP exception, fsr was %016lx\n", fpt->thread.fsr);
228#endif
229
230 switch ((fpt->thread.fsr & 0x1c000)) {
231 /* switch on the contents of the ftt [floating point trap type] field */
232#ifdef DEBUG_FPU
233 case (1 << 14):
234 printk("IEEE_754_exception\n");
235 break;
236#endif
237 case (2 << 14): /* unfinished_FPop (underflow & co) */
238 case (3 << 14): /* unimplemented_FPop (quad stuff, maybe sqrt) */
239 ret = do_mathemu(regs, fpt);
240 break;
241#ifdef DEBUG_FPU
242 case (4 << 14):
243 printk("sequence_error (OS bug...)\n");
244 break;
245 case (5 << 14):
246 printk("hardware_error (uhoh!)\n");
247 break;
248 case (6 << 14):
249 printk("invalid_fp_register (user error)\n");
250 break;
251#endif /* DEBUG_FPU */
252 }
253 /* If we successfully emulated the FPop, we pretend the trap never happened :-> */
254 if (ret) {
255 fpload(¤t->thread.float_regs[0], ¤t->thread.fsr);
256 return;
257 }
258 /* nope, better SIGFPE the offending process... */
259
260#ifdef CONFIG_SMP
261 clear_tsk_thread_flag(fpt, TIF_USEDFPU);
262#endif
263 if(psr & PSR_PS) {
264 /* The first fsr store/load we tried trapped,
265 * the second one will not (we hope).
266 */
267 printk("WARNING: FPU exception from kernel mode. at pc=%08lx\n",
268 regs->pc);
269 regs->pc = regs->npc;
270 regs->npc += 4;
271 calls++;
272 if(calls > 2)
273 die_if_kernel("Too many Penguin-FPU traps from kernel mode",
274 regs);
275 return;
276 }
277
278 fsr = fpt->thread.fsr;
279 code = FPE_FLTUNK;
280 if ((fsr & 0x1c000) == (1 << 14)) {
281 if (fsr & 0x10)
282 code = FPE_FLTINV;
283 else if (fsr & 0x08)
284 code = FPE_FLTOVF;
285 else if (fsr & 0x04)
286 code = FPE_FLTUND;
287 else if (fsr & 0x02)
288 code = FPE_FLTDIV;
289 else if (fsr & 0x01)
290 code = FPE_FLTRES;
291 }
292 send_sig_fault(SIGFPE, code, (void __user *)pc, fpt);
293#ifndef CONFIG_SMP
294 last_task_used_math = NULL;
295#endif
296 regs->psr &= ~PSR_EF;
297 if(calls > 0)
298 calls=0;
299}
300
301void handle_tag_overflow(struct pt_regs *regs, unsigned long pc, unsigned long npc,
302 unsigned long psr)
303{
304 if(psr & PSR_PS)
305 die_if_kernel("Penguin overflow trap from kernel mode", regs);
306 send_sig_fault(SIGEMT, EMT_TAGOVF, (void __user *)pc, current);
307}
308
309void handle_watchpoint(struct pt_regs *regs, unsigned long pc, unsigned long npc,
310 unsigned long psr)
311{
312#ifdef TRAP_DEBUG
313 printk("Watchpoint detected at PC %08lx NPC %08lx PSR %08lx\n",
314 pc, npc, psr);
315#endif
316 if(psr & PSR_PS)
317 panic("Tell me what a watchpoint trap is, and I'll then deal "
318 "with such a beast...");
319}
320
321void handle_reg_access(struct pt_regs *regs, unsigned long pc, unsigned long npc,
322 unsigned long psr)
323{
324#ifdef TRAP_DEBUG
325 printk("Register Access Exception at PC %08lx NPC %08lx PSR %08lx\n",
326 pc, npc, psr);
327#endif
328 force_sig_fault(SIGBUS, BUS_OBJERR, (void __user *)pc);
329}
330
331void handle_cp_disabled(struct pt_regs *regs, unsigned long pc, unsigned long npc,
332 unsigned long psr)
333{
334 send_sig_fault(SIGILL, ILL_COPROC, (void __user *)pc, current);
335}
336
337void handle_cp_exception(struct pt_regs *regs, unsigned long pc, unsigned long npc,
338 unsigned long psr)
339{
340#ifdef TRAP_DEBUG
341 printk("Co-Processor Exception at PC %08lx NPC %08lx PSR %08lx\n",
342 pc, npc, psr);
343#endif
344 send_sig_fault(SIGILL, ILL_COPROC, (void __user *)pc, current);
345}
346
347void handle_hw_divzero(struct pt_regs *regs, unsigned long pc, unsigned long npc,
348 unsigned long psr)
349{
350 send_sig_fault(SIGFPE, FPE_INTDIV, (void __user *)pc, current);
351}
352
353#ifdef CONFIG_DEBUG_BUGVERBOSE
354void do_BUG(const char *file, int line)
355{
356 // bust_spinlocks(1); XXX Not in our original BUG()
357 printk("kernel BUG at %s:%d!\n", file, line);
358}
359EXPORT_SYMBOL(do_BUG);
360#endif
361
362/* Since we have our mappings set up, on multiprocessors we can spin them
363 * up here so that timer interrupts work during initialization.
364 */
365
366void trap_init(void)
367{
368 extern void thread_info_offsets_are_bolixed_pete(void);
369
370 /* Force linker to barf if mismatched */
371 if (TI_UWINMASK != offsetof(struct thread_info, uwinmask) ||
372 TI_TASK != offsetof(struct thread_info, task) ||
373 TI_FLAGS != offsetof(struct thread_info, flags) ||
374 TI_CPU != offsetof(struct thread_info, cpu) ||
375 TI_PREEMPT != offsetof(struct thread_info, preempt_count) ||
376 TI_SOFTIRQ != offsetof(struct thread_info, softirq_count) ||
377 TI_HARDIRQ != offsetof(struct thread_info, hardirq_count) ||
378 TI_KSP != offsetof(struct thread_info, ksp) ||
379 TI_KPC != offsetof(struct thread_info, kpc) ||
380 TI_KPSR != offsetof(struct thread_info, kpsr) ||
381 TI_KWIM != offsetof(struct thread_info, kwim) ||
382 TI_REG_WINDOW != offsetof(struct thread_info, reg_window) ||
383 TI_RWIN_SPTRS != offsetof(struct thread_info, rwbuf_stkptrs) ||
384 TI_W_SAVED != offsetof(struct thread_info, w_saved))
385 thread_info_offsets_are_bolixed_pete();
386
387 /* Attach to the address space of init_task. */
388 mmgrab(&init_mm);
389 current->active_mm = &init_mm;
390
391 /* NOTE: Other cpus have this done as they are started
392 * up on SMP.
393 */
394}