summaryrefslogtreecommitdiffstats
path: root/arch/powerpc/kernel/mce_power.c
blob: 6b800eec31f2fe16bda42e896e30eb3a2e31e6dd (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
/*
 * Machine check exception handling CPU-side for power7 and power8
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 *
 * Copyright 2013 IBM Corporation
 * Author: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
 */

#undef DEBUG
#define pr_fmt(fmt) "mce_power: " fmt

#include <linux/types.h>
#include <linux/ptrace.h>
#include <asm/mmu.h>
#include <asm/mce.h>
#include <asm/machdep.h>
#include <asm/pgtable.h>
#include <asm/pte-walk.h>
#include <asm/sstep.h>
#include <asm/exception-64s.h>

/*
 * Convert an address related to an mm to a PFN. NOTE: we are in real
 * mode, we could potentially race with page table updates.
 */
static unsigned long addr_to_pfn(struct pt_regs *regs, unsigned long addr)
{
	pte_t *ptep;
	unsigned long flags;
	struct mm_struct *mm;

	if (user_mode(regs))
		mm = current->mm;
	else
		mm = &init_mm;

	local_irq_save(flags);
	if (mm == current->mm)
		ptep = find_current_mm_pte(mm->pgd, addr, NULL, NULL);
	else
		ptep = find_init_mm_pte(addr, NULL);
	local_irq_restore(flags);
	if (!ptep || pte_special(*ptep))
		return ULONG_MAX;
	return pte_pfn(*ptep);
}

/* flush SLBs and reload */
#ifdef CONFIG_PPC_BOOK3S_64
void flush_and_reload_slb(void)
{
	/* Invalidate all SLBs */
	slb_flush_all_realmode();

#ifdef CONFIG_KVM_BOOK3S_HANDLER
	/*
	 * If machine check is hit when in guest or in transition, we will
	 * only flush the SLBs and continue.
	 */
	if (get_paca()->kvm_hstate.in_guest)
		return;
#endif
	if (early_radix_enabled())
		return;

	/*
	 * This probably shouldn't happen, but it may be possible it's
	 * called in early boot before SLB shadows are allocated.
	 */
	if (!get_slb_shadow())
		return;

	slb_restore_bolted_realmode();
}
#endif

static void flush_erat(void)
{
#ifdef CONFIG_PPC_BOOK3S_64
	if (!early_cpu_has_feature(CPU_FTR_ARCH_300)) {
		flush_and_reload_slb();
		return;
	}
#endif
	/* PPC_INVALIDATE_ERAT can only be used on ISA v3 and newer */
	asm volatile(PPC_INVALIDATE_ERAT : : :"memory");
}

#define MCE_FLUSH_SLB 1
#define MCE_FLUSH_TLB 2
#define MCE_FLUSH_ERAT 3

static int mce_flush(int what)
{
#ifdef CONFIG_PPC_BOOK3S_64
	if (what == MCE_FLUSH_SLB) {
		flush_and_reload_slb();
		return 1;
	}
#endif
	if (what == MCE_FLUSH_ERAT) {
		flush_erat();
		return 1;
	}
	if (what == MCE_FLUSH_TLB) {
		tlbiel_all();
		return 1;
	}

	return 0;
}

#define SRR1_MC_LOADSTORE(srr1)	((srr1) & PPC_BIT(42))

struct mce_ierror_table {
	unsigned long srr1_mask;
	unsigned long srr1_value;
	bool nip_valid; /* nip is a valid indicator of faulting address */
	unsigned int error_type;
	unsigned int error_subtype;
	unsigned int initiator;
	unsigned int severity;
};

static const struct mce_ierror_table mce_p7_ierror_table[] = {
{ 0x00000000001c0000, 0x0000000000040000, true,
  MCE_ERROR_TYPE_UE,  MCE_UE_ERROR_IFETCH,
  MCE_INITIATOR_CPU,  MCE_SEV_ERROR_SYNC, },
{ 0x00000000001c0000, 0x0000000000080000, true,
  MCE_ERROR_TYPE_SLB, MCE_SLB_ERROR_PARITY,
  MCE_INITIATOR_CPU,  MCE_SEV_ERROR_SYNC, },
{ 0x00000000001c0000, 0x00000000000c0000, true,
  MCE_ERROR_TYPE_SLB, MCE_SLB_ERROR_MULTIHIT,
  MCE_INITIATOR_CPU,  MCE_SEV_ERROR_SYNC, },
{ 0x00000000001c0000, 0x0000000000100000, true,
  MCE_ERROR_TYPE_SLB, MCE_SLB_ERROR_INDETERMINATE, /* BOTH */
  MCE_INITIATOR_CPU,  MCE_SEV_ERROR_SYNC, },
{ 0x00000000001c0000, 0x0000000000140000, true,
  MCE_ERROR_TYPE_TLB, MCE_TLB_ERROR_MULTIHIT,
  MCE_INITIATOR_CPU,  MCE_SEV_ERROR_SYNC, },
{ 0x00000000001c0000, 0x0000000000180000, true,
  MCE_ERROR_TYPE_UE,  MCE_UE_ERROR_PAGE_TABLE_WALK_IFETCH,
  MCE_INITIATOR_CPU,  MCE_SEV_ERROR_SYNC, },
{ 0x00000000001c0000, 0x00000000001c0000, true,
  MCE_ERROR_TYPE_UE,  MCE_UE_ERROR_IFETCH,
  MCE_INITIATOR_CPU,  MCE_SEV_ERROR_SYNC, },
{ 0, 0, 0, 0, 0, 0 } };

static const struct mce_ierror_table mce_p8_ierror_table[] = {
{ 0x00000000081c0000, 0x0000000000040000, true,
  MCE_ERROR_TYPE_UE,  MCE_UE_ERROR_IFETCH,
  MCE_INITIATOR_CPU,  MCE_SEV_ERROR_SYNC, },
{ 0x00000000081c0000, 0x0000000000080000, true,
  MCE_ERROR_TYPE_SLB, MCE_SLB_ERROR_PARITY,
  MCE_INITIATOR_CPU,  MCE_SEV_ERROR_SYNC, },
{ 0x00000000081c0000, 0x00000000000c0000, true,
  MCE_ERROR_TYPE_SLB, MCE_SLB_ERROR_MULTIHIT,
  MCE_INITIATOR_CPU,  MCE_SEV_ERROR_SYNC, },
{ 0x00000000081c0000, 0x0000000000100000, true,
  MCE_ERROR_TYPE_ERAT,MCE_ERAT_ERROR_MULTIHIT,
  MCE_INITIATOR_CPU,  MCE_SEV_ERROR_SYNC, },
{ 0x00000000081c0000, 0x0000000000140000, true,
  MCE_ERROR_TYPE_TLB, MCE_TLB_ERROR_MULTIHIT,
  MCE_INITIATOR_CPU,  MCE_SEV_ERROR_SYNC, },
{ 0x00000000081c0000, 0x0000000000180000, true,
  MCE_ERROR_TYPE_UE,  MCE_UE_ERROR_PAGE_TABLE_WALK_IFETCH,
  MCE_INITIATOR_CPU,  MCE_SEV_ERROR_SYNC, },
{ 0x00000000081c0000, 0x00000000001c0000, true,
  MCE_ERROR_TYPE_UE,  MCE_UE_ERROR_IFETCH,
  MCE_INITIATOR_CPU,  MCE_SEV_ERROR_SYNC, },
{ 0x00000000081c0000, 0x0000000008000000, true,
  MCE_ERROR_TYPE_LINK,MCE_LINK_ERROR_IFETCH_TIMEOUT,
  MCE_INITIATOR_CPU,  MCE_SEV_ERROR_SYNC, },
{ 0x00000000081c0000, 0x0000000008040000, true,
  MCE_ERROR_TYPE_LINK,MCE_LINK_ERROR_PAGE_TABLE_WALK_IFETCH_TIMEOUT,
  MCE_INITIATOR_CPU,  MCE_SEV_ERROR_SYNC, },
{ 0, 0, 0, 0, 0, 0 } };

static const struct mce_ierror_table mce_p9_ierror_table[] = {
{ 0x00000000081c0000, 0x0000000000040000, true,
  MCE_ERROR_TYPE_UE,  MCE_UE_ERROR_IFETCH,
  MCE_INITIATOR_CPU,  MCE_SEV_ERROR_SYNC, },
{ 0x00000000081c0000, 0x0000000000080000, true,
  MCE_ERROR_TYPE_SLB, MCE_SLB_ERROR_PARITY,
  MCE_INITIATOR_CPU,  MCE_SEV_ERROR_SYNC, },
{ 0x00000000081c0000, 0x00000000000c0000, true,
  MCE_ERROR_TYPE_SLB, MCE_SLB_ERROR_MULTIHIT,
  MCE_INITIATOR_CPU,  MCE_SEV_ERROR_SYNC, },
{ 0x00000000081c0000, 0x0000000000100000, true,
  MCE_ERROR_TYPE_ERAT,MCE_ERAT_ERROR_MULTIHIT,
  MCE_INITIATOR_CPU,  MCE_SEV_ERROR_SYNC, },
{ 0x00000000081c0000, 0x0000000000140000, true,
  MCE_ERROR_TYPE_TLB, MCE_TLB_ERROR_MULTIHIT,
  MCE_INITIATOR_CPU,  MCE_SEV_ERROR_SYNC, },
{ 0x00000000081c0000, 0x0000000000180000, true,
  MCE_ERROR_TYPE_UE,  MCE_UE_ERROR_PAGE_TABLE_WALK_IFETCH,
  MCE_INITIATOR_CPU,  MCE_SEV_ERROR_SYNC, },
{ 0x00000000081c0000, 0x00000000001c0000, true,
  MCE_ERROR_TYPE_RA,  MCE_RA_ERROR_IFETCH_FOREIGN,
  MCE_INITIATOR_CPU,  MCE_SEV_ERROR_SYNC, },
{ 0x00000000081c0000, 0x0000000008000000, true,
  MCE_ERROR_TYPE_LINK,MCE_LINK_ERROR_IFETCH_TIMEOUT,
  MCE_INITIATOR_CPU,  MCE_SEV_ERROR_SYNC, },
{ 0x00000000081c0000, 0x0000000008040000, true,
  MCE_ERROR_TYPE_LINK,MCE_LINK_ERROR_PAGE_TABLE_WALK_IFETCH_TIMEOUT,
  MCE_INITIATOR_CPU,  MCE_SEV_ERROR_SYNC, },
{ 0x00000000081c0000, 0x00000000080c0000, true,
  MCE_ERROR_TYPE_RA,  MCE_RA_ERROR_IFETCH,
  MCE_INITIATOR_CPU,  MCE_SEV_ERROR_SYNC, },
{ 0x00000000081c0000, 0x0000000008100000, true,
  MCE_ERROR_TYPE_RA,  MCE_RA_ERROR_PAGE_TABLE_WALK_IFETCH,
  MCE_INITIATOR_CPU,  MCE_SEV_ERROR_SYNC, },
{ 0x00000000081c0000, 0x0000000008140000, false,
  MCE_ERROR_TYPE_RA,  MCE_RA_ERROR_STORE,
  MCE_INITIATOR_CPU,  MCE_SEV_FATAL, }, /* ASYNC is fatal */
{ 0x00000000081c0000, 0x0000000008180000, false,
  MCE_ERROR_TYPE_LINK,MCE_LINK_ERROR_STORE_TIMEOUT,
  MCE_INITIATOR_CPU,  MCE_SEV_FATAL, }, /* ASYNC is fatal */
{ 0x00000000081c0000, 0x00000000081c0000, true,
  MCE_ERROR_TYPE_RA,  MCE_RA_ERROR_PAGE_TABLE_WALK_IFETCH_FOREIGN,
  MCE_INITIATOR_CPU,  MCE_SEV_ERROR_SYNC, },
{ 0, 0, 0, 0, 0, 0 } };

struct mce_derror_table {
	unsigned long dsisr_value;
	bool dar_valid; /* dar is a valid indicator of faulting address */
	unsigned int error_type;
	unsigned int error_subtype;
	unsigned int initiator;
	unsigned int severity;
};

static const struct mce_derror_table mce_p7_derror_table[] = {
{ 0x00008000, false,
  MCE_ERROR_TYPE_UE,   MCE_UE_ERROR_LOAD_STORE,
  MCE_INITIATOR_CPU,   MCE_SEV_ERROR_SYNC, },
{ 0x00004000, true,
  MCE_ERROR_TYPE_UE,   MCE_UE_ERROR_PAGE_TABLE_WALK_LOAD_STORE,
  MCE_INITIATOR_CPU,   MCE_SEV_ERROR_SYNC, },
{ 0x00000800, true,
  MCE_ERROR_TYPE_ERAT, MCE_ERAT_ERROR_MULTIHIT,
  MCE_INITIATOR_CPU,   MCE_SEV_ERROR_SYNC, },
{ 0x00000400, true,
  MCE_ERROR_TYPE_TLB,  MCE_TLB_ERROR_MULTIHIT,
  MCE_INITIATOR_CPU,   MCE_SEV_ERROR_SYNC, },
{ 0x00000080, true,
  MCE_ERROR_TYPE_SLB,  MCE_SLB_ERROR_MULTIHIT,	/* Before PARITY */
  MCE_INITIATOR_CPU,   MCE_SEV_ERROR_SYNC, },
{ 0x00000100, true,
  MCE_ERROR_TYPE_SLB,  MCE_SLB_ERROR_PARITY,
  MCE_INITIATOR_CPU,   MCE_SEV_ERROR_SYNC, },
{ 0x00000040, true,
  MCE_ERROR_TYPE_SLB,  MCE_SLB_ERROR_INDETERMINATE, /* BOTH */
  MCE_INITIATOR_CPU,   MCE_SEV_ERROR_SYNC, },
{ 0, false, 0, 0, 0, 0 } };

static const struct mce_derror_table mce_p8_derror_table[] = {
{ 0x00008000, false,
  MCE_ERROR_TYPE_UE,   MCE_UE_ERROR_LOAD_STORE,
  MCE_INITIATOR_CPU,   MCE_SEV_ERROR_SYNC, },
{ 0x00004000, true,
  MCE_ERROR_TYPE_UE,   MCE_UE_ERROR_PAGE_TABLE_WALK_LOAD_STORE,
  MCE_INITIATOR_CPU,   MCE_SEV_ERROR_SYNC, },
{ 0x00002000, true,
  MCE_ERROR_TYPE_LINK, MCE_LINK_ERROR_LOAD_TIMEOUT,
  MCE_INITIATOR_CPU,   MCE_SEV_ERROR_SYNC, },
{ 0x00001000, true,
  MCE_ERROR_TYPE_LINK, MCE_LINK_ERROR_PAGE_TABLE_WALK_LOAD_STORE_TIMEOUT,
  MCE_INITIATOR_CPU,   MCE_SEV_ERROR_SYNC, },
{ 0x00000800, true,
  MCE_ERROR_TYPE_ERAT, MCE_ERAT_ERROR_MULTIHIT,
  MCE_INITIATOR_CPU,   MCE_SEV_ERROR_SYNC, },
{ 0x00000400, true,
  MCE_ERROR_TYPE_TLB,  MCE_TLB_ERROR_MULTIHIT,
  MCE_INITIATOR_CPU,   MCE_SEV_ERROR_SYNC, },
{ 0x00000200, true,
  MCE_ERROR_TYPE_ERAT, MCE_ERAT_ERROR_MULTIHIT, /* SECONDARY ERAT */
  MCE_INITIATOR_CPU,   MCE_SEV_ERROR_SYNC, },
{ 0x00000080, true,
  MCE_ERROR_TYPE_SLB,  MCE_SLB_ERROR_MULTIHIT,	/* Before PARITY */
  MCE_INITIATOR_CPU,   MCE_SEV_ERROR_SYNC, },
{ 0x00000100, true,
  MCE_ERROR_TYPE_SLB,  MCE_SLB_ERROR_PARITY,
  MCE_INITIATOR_CPU,   MCE_SEV_ERROR_SYNC, },
{ 0, false, 0, 0, 0, 0 } };

static const struct mce_derror_table mce_p9_derror_table[] = {
{ 0x00008000, false,
  MCE_ERROR_TYPE_UE,   MCE_UE_ERROR_LOAD_STORE,
  MCE_INITIATOR_CPU,   MCE_SEV_ERROR_SYNC, },
{ 0x00004000, true,
  MCE_ERROR_TYPE_UE,   MCE_UE_ERROR_PAGE_TABLE_WALK_LOAD_STORE,
  MCE_INITIATOR_CPU,   MCE_SEV_ERROR_SYNC, },
{ 0x00002000, true,
  MCE_ERROR_TYPE_LINK, MCE_LINK_ERROR_LOAD_TIMEOUT,
  MCE_INITIATOR_CPU,   MCE_SEV_ERROR_SYNC, },
{ 0x00001000, true,
  MCE_ERROR_TYPE_LINK, MCE_LINK_ERROR_PAGE_TABLE_WALK_LOAD_STORE_TIMEOUT,
  MCE_INITIATOR_CPU,   MCE_SEV_ERROR_SYNC, },
{ 0x00000800, true,
  MCE_ERROR_TYPE_ERAT, MCE_ERAT_ERROR_MULTIHIT,
  MCE_INITIATOR_CPU,   MCE_SEV_ERROR_SYNC, },
{ 0x00000400, true,
  MCE_ERROR_TYPE_TLB,  MCE_TLB_ERROR_MULTIHIT,
  MCE_INITIATOR_CPU,   MCE_SEV_ERROR_SYNC, },
{ 0x00000200, false,
  MCE_ERROR_TYPE_USER, MCE_USER_ERROR_TLBIE,
  MCE_INITIATOR_CPU,   MCE_SEV_ERROR_SYNC, },
{ 0x00000080, true,
  MCE_ERROR_TYPE_SLB,  MCE_SLB_ERROR_MULTIHIT,	/* Before PARITY */
  MCE_INITIATOR_CPU,   MCE_SEV_ERROR_SYNC, },
{ 0x00000100, true,
  MCE_ERROR_TYPE_SLB,  MCE_SLB_ERROR_PARITY,
  MCE_INITIATOR_CPU,   MCE_SEV_ERROR_SYNC, },
{ 0x00000040, true,
  MCE_ERROR_TYPE_RA,   MCE_RA_ERROR_LOAD,
  MCE_INITIATOR_CPU,   MCE_SEV_ERROR_SYNC, },
{ 0x00000020, false,
  MCE_ERROR_TYPE_RA,   MCE_RA_ERROR_PAGE_TABLE_WALK_LOAD_STORE,
  MCE_INITIATOR_CPU,   MCE_SEV_ERROR_SYNC, },
{ 0x00000010, false,
  MCE_ERROR_TYPE_RA,   MCE_RA_ERROR_PAGE_TABLE_WALK_LOAD_STORE_FOREIGN,
  MCE_INITIATOR_CPU,   MCE_SEV_ERROR_SYNC, },
{ 0x00000008, false,
  MCE_ERROR_TYPE_RA,   MCE_RA_ERROR_LOAD_STORE_FOREIGN,
  MCE_INITIATOR_CPU,   MCE_SEV_ERROR_SYNC, },
{ 0, false, 0, 0, 0, 0 } };

static int mce_find_instr_ea_and_pfn(struct pt_regs *regs, uint64_t *addr,
					uint64_t *phys_addr)
{
	/*
	 * Carefully look at the NIP to determine
	 * the instruction to analyse. Reading the NIP
	 * in real-mode is tricky and can lead to recursive
	 * faults
	 */
	int instr;
	unsigned long pfn, instr_addr;
	struct instruction_op op;
	struct pt_regs tmp = *regs;

	pfn = addr_to_pfn(regs, regs->nip);
	if (pfn != ULONG_MAX) {
		instr_addr = (pfn << PAGE_SHIFT) + (regs->nip & ~PAGE_MASK);
		instr = *(unsigned int *)(instr_addr);
		if (!analyse_instr(&op, &tmp, instr)) {
			pfn = addr_to_pfn(regs, op.ea);
			*addr = op.ea;
			*phys_addr = (pfn << PAGE_SHIFT);
			return 0;
		}
		/*
		 * analyse_instr() might fail if the instruction
		 * is not a load/store, although this is unexpected
		 * for load/store errors or if we got the NIP
		 * wrong
		 */
	}
	*addr = 0;
	return -1;
}

static int mce_handle_ierror(struct pt_regs *regs,
		const struct mce_ierror_table table[],
		struct mce_error_info *mce_err, uint64_t *addr,
		uint64_t *phys_addr)
{
	uint64_t srr1 = regs->msr;
	int handled = 0;
	int i;

	*addr = 0;

	for (i = 0; table[i].srr1_mask; i++) {
		if ((srr1 & table[i].srr1_mask) != table[i].srr1_value)
			continue;

		/* attempt to correct the error */
		switch (table[i].error_type) {
		case MCE_ERROR_TYPE_SLB:
			handled = mce_flush(MCE_FLUSH_SLB);
			break;
		case MCE_ERROR_TYPE_ERAT:
			handled = mce_flush(MCE_FLUSH_ERAT);
			break;
		case MCE_ERROR_TYPE_TLB:
			handled = mce_flush(MCE_FLUSH_TLB);
			break;
		}

		/* now fill in mce_error_info */
		mce_err->error_type = table[i].error_type;
		switch (table[i].error_type) {
		case MCE_ERROR_TYPE_UE:
			mce_err->u.ue_error_type = table[i].error_subtype;
			break;
		case MCE_ERROR_TYPE_SLB:
			mce_err->u.slb_error_type = table[i].error_subtype;
			break;
		case MCE_ERROR_TYPE_ERAT:
			mce_err->u.erat_error_type = table[i].error_subtype;
			break;
		case MCE_ERROR_TYPE_TLB:
			mce_err->u.tlb_error_type = table[i].error_subtype;
			break;
		case MCE_ERROR_TYPE_USER:
			mce_err->u.user_error_type = table[i].error_subtype;
			break;
		case MCE_ERROR_TYPE_RA:
			mce_err->u.ra_error_type = table[i].error_subtype;
			break;
		case MCE_ERROR_TYPE_LINK:
			mce_err->u.link_error_type = table[i].error_subtype;
			break;
		}
		mce_err->severity = table[i].severity;
		mce_err->initiator = table[i].initiator;
		if (table[i].nip_valid) {
			*addr = regs->nip;
			if (mce_err->severity == MCE_SEV_ERROR_SYNC &&
				table[i].error_type == MCE_ERROR_TYPE_UE) {
				unsigned long pfn;

				if (get_paca()->in_mce < MAX_MCE_DEPTH) {
					pfn = addr_to_pfn(regs, regs->nip);
					if (pfn != ULONG_MAX) {
						*phys_addr =
							(pfn << PAGE_SHIFT);
					}
				}
			}
		}
		return handled;
	}

	mce_err->error_type = MCE_ERROR_TYPE_UNKNOWN;
	mce_err->severity = MCE_SEV_ERROR_SYNC;
	mce_err->initiator = MCE_INITIATOR_CPU;

	return 0;
}

static int mce_handle_derror(struct pt_regs *regs,
		const struct mce_derror_table table[],
		struct mce_error_info *mce_err, uint64_t *addr,
		uint64_t *phys_addr)
{
	uint64_t dsisr = regs->dsisr;
	int handled = 0;
	int found = 0;
	int i;

	*addr = 0;

	for (i = 0; table[i].dsisr_value; i++) {
		if (!(dsisr & table[i].dsisr_value))
			continue;

		/* attempt to correct the error */
		switch (table[i].error_type) {
		case MCE_ERROR_TYPE_SLB:
			if (mce_flush(MCE_FLUSH_SLB))
				handled = 1;
			break;
		case MCE_ERROR_TYPE_ERAT:
			if (mce_flush(MCE_FLUSH_ERAT))
				handled = 1;
			break;
		case MCE_ERROR_TYPE_TLB:
			if (mce_flush(MCE_FLUSH_TLB))
				handled = 1;
			break;
		}

		/*
		 * Attempt to handle multiple conditions, but only return
		 * one. Ensure uncorrectable errors are first in the table
		 * to match.
		 */
		if (found)
			continue;

		/* now fill in mce_error_info */
		mce_err->error_type = table[i].error_type;
		switch (table[i].error_type) {
		case MCE_ERROR_TYPE_UE:
			mce_err->u.ue_error_type = table[i].error_subtype;
			break;
		case MCE_ERROR_TYPE_SLB:
			mce_err->u.slb_error_type = table[i].error_subtype;
			break;
		case MCE_ERROR_TYPE_ERAT:
			mce_err->u.erat_error_type = table[i].error_subtype;
			break;
		case MCE_ERROR_TYPE_TLB:
			mce_err->u.tlb_error_type = table[i].error_subtype;
			break;
		case MCE_ERROR_TYPE_USER:
			mce_err->u.user_error_type = table[i].error_subtype;
			break;
		case MCE_ERROR_TYPE_RA:
			mce_err->u.ra_error_type = table[i].error_subtype;
			break;
		case MCE_ERROR_TYPE_LINK:
			mce_err->u.link_error_type = table[i].error_subtype;
			break;
		}
		mce_err->severity = table[i].severity;
		mce_err->initiator = table[i].initiator;
		if (table[i].dar_valid)
			*addr = regs->dar;
		else if (mce_err->severity == MCE_SEV_ERROR_SYNC &&
				table[i].error_type == MCE_ERROR_TYPE_UE) {
			/*
			 * We do a maximum of 4 nested MCE calls, see
			 * kernel/exception-64s.h
			 */
			if (get_paca()->in_mce < MAX_MCE_DEPTH)
				mce_find_instr_ea_and_pfn(regs, addr, phys_addr);
		}
		found = 1;
	}

	if (found)
		return handled;

	mce_err->error_type = MCE_ERROR_TYPE_UNKNOWN;
	mce_err->severity = MCE_SEV_ERROR_SYNC;
	mce_err->initiator = MCE_INITIATOR_CPU;

	return 0;
}

static long mce_handle_ue_error(struct pt_regs *regs)
{
	long handled = 0;

	/*
	 * On specific SCOM read via MMIO we may get a machine check
	 * exception with SRR0 pointing inside opal. If that is the
	 * case OPAL may have recovery address to re-read SCOM data in
	 * different way and hence we can recover from this MC.
	 */

	if (ppc_md.mce_check_early_recovery) {
		if (ppc_md.mce_check_early_recovery(regs))
			handled = 1;
	}
	return handled;
}

static long mce_handle_error(struct pt_regs *regs,
		const struct mce_derror_table dtable[],
		const struct mce_ierror_table itable[])
{
	struct mce_error_info mce_err = { 0 };
	uint64_t addr, phys_addr = ULONG_MAX;
	uint64_t srr1 = regs->msr;
	long handled;

	if (SRR1_MC_LOADSTORE(srr1))
		handled = mce_handle_derror(regs, dtable, &mce_err, &addr,
				&phys_addr);
	else
		handled = mce_handle_ierror(regs, itable, &mce_err, &addr,
				&phys_addr);

	if (!handled && mce_err.error_type == MCE_ERROR_TYPE_UE)
		handled = mce_handle_ue_error(regs);

	save_mce_event(regs, handled, &mce_err, regs->nip, addr, phys_addr);

	return handled;
}

long __machine_check_early_realmode_p7(struct pt_regs *regs)
{
	/* P7 DD1 leaves top bits of DSISR undefined */
	regs->dsisr &= 0x0000ffff;

	return mce_handle_error(regs, mce_p7_derror_table, mce_p7_ierror_table);
}

long __machine_check_early_realmode_p8(struct pt_regs *regs)
{
	return mce_handle_error(regs, mce_p8_derror_table, mce_p8_ierror_table);
}

long __machine_check_early_realmode_p9(struct pt_regs *regs)
{
	/*
	 * On POWER9 DD2.1 and below, it's possible to get a machine check
	 * caused by a paste instruction where only DSISR bit 25 is set. This
	 * will result in the MCE handler seeing an unknown event and the kernel
	 * crashing. An MCE that occurs like this is spurious, so we don't need
	 * to do anything in terms of servicing it. If there is something that
	 * needs to be serviced, the CPU will raise the MCE again with the
	 * correct DSISR so that it can be serviced properly. So detect this
	 * case and mark it as handled.
	 */
	if (SRR1_MC_LOADSTORE(regs->msr) && regs->dsisr == 0x02000000)
		return 1;

	return mce_handle_error(regs, mce_p9_derror_table, mce_p9_ierror_table);
}