xref: /openbmc/linux/arch/powerpc/kernel/mce_power.c (revision 55fd7e02)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Machine check exception handling CPU-side for power7 and power8
4  *
5  * Copyright 2013 IBM Corporation
6  * Author: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
7  */
8 
9 #undef DEBUG
10 #define pr_fmt(fmt) "mce_power: " fmt
11 
12 #include <linux/types.h>
13 #include <linux/ptrace.h>
14 #include <linux/extable.h>
15 #include <linux/pgtable.h>
16 #include <asm/mmu.h>
17 #include <asm/mce.h>
18 #include <asm/machdep.h>
19 #include <asm/pte-walk.h>
20 #include <asm/sstep.h>
21 #include <asm/exception-64s.h>
22 #include <asm/extable.h>
23 #include <asm/inst.h>
24 
25 /*
26  * Convert an address related to an mm to a PFN. NOTE: we are in real
27  * mode, we could potentially race with page table updates.
28  */
29 unsigned long addr_to_pfn(struct pt_regs *regs, unsigned long addr)
30 {
31 	pte_t *ptep, pte;
32 	unsigned int shift;
33 	unsigned long pfn, flags;
34 	struct mm_struct *mm;
35 
36 	if (user_mode(regs))
37 		mm = current->mm;
38 	else
39 		mm = &init_mm;
40 
41 	local_irq_save(flags);
42 	ptep = __find_linux_pte(mm->pgd, addr, NULL, &shift);
43 	if (!ptep) {
44 		pfn = ULONG_MAX;
45 		goto out;
46 	}
47 	pte = READ_ONCE(*ptep);
48 
49 	if (!pte_present(pte) || pte_special(pte)) {
50 		pfn = ULONG_MAX;
51 		goto out;
52 	}
53 
54 	if (shift <= PAGE_SHIFT)
55 		pfn = pte_pfn(pte);
56 	else {
57 		unsigned long rpnmask = (1ul << shift) - PAGE_SIZE;
58 		pfn = pte_pfn(__pte(pte_val(pte) | (addr & rpnmask)));
59 	}
60 out:
61 	local_irq_restore(flags);
62 	return pfn;
63 }
64 
65 /* flush SLBs and reload */
66 #ifdef CONFIG_PPC_BOOK3S_64
67 void flush_and_reload_slb(void)
68 {
69 	/* Invalidate all SLBs */
70 	slb_flush_all_realmode();
71 
72 #ifdef CONFIG_KVM_BOOK3S_HANDLER
73 	/*
74 	 * If machine check is hit when in guest or in transition, we will
75 	 * only flush the SLBs and continue.
76 	 */
77 	if (get_paca()->kvm_hstate.in_guest)
78 		return;
79 #endif
80 	if (early_radix_enabled())
81 		return;
82 
83 	/*
84 	 * This probably shouldn't happen, but it may be possible it's
85 	 * called in early boot before SLB shadows are allocated.
86 	 */
87 	if (!get_slb_shadow())
88 		return;
89 
90 	slb_restore_bolted_realmode();
91 }
92 #endif
93 
94 static void flush_erat(void)
95 {
96 #ifdef CONFIG_PPC_BOOK3S_64
97 	if (!early_cpu_has_feature(CPU_FTR_ARCH_300)) {
98 		flush_and_reload_slb();
99 		return;
100 	}
101 #endif
102 	asm volatile(PPC_ISA_3_0_INVALIDATE_ERAT : : :"memory");
103 }
104 
105 #define MCE_FLUSH_SLB 1
106 #define MCE_FLUSH_TLB 2
107 #define MCE_FLUSH_ERAT 3
108 
109 static int mce_flush(int what)
110 {
111 #ifdef CONFIG_PPC_BOOK3S_64
112 	if (what == MCE_FLUSH_SLB) {
113 		flush_and_reload_slb();
114 		return 1;
115 	}
116 #endif
117 	if (what == MCE_FLUSH_ERAT) {
118 		flush_erat();
119 		return 1;
120 	}
121 	if (what == MCE_FLUSH_TLB) {
122 		tlbiel_all();
123 		return 1;
124 	}
125 
126 	return 0;
127 }
128 
129 #define SRR1_MC_LOADSTORE(srr1)	((srr1) & PPC_BIT(42))
130 
131 struct mce_ierror_table {
132 	unsigned long srr1_mask;
133 	unsigned long srr1_value;
134 	bool nip_valid; /* nip is a valid indicator of faulting address */
135 	unsigned int error_type;
136 	unsigned int error_subtype;
137 	unsigned int error_class;
138 	unsigned int initiator;
139 	unsigned int severity;
140 	bool sync_error;
141 };
142 
143 static const struct mce_ierror_table mce_p7_ierror_table[] = {
144 { 0x00000000001c0000, 0x0000000000040000, true,
145   MCE_ERROR_TYPE_UE,  MCE_UE_ERROR_IFETCH, MCE_ECLASS_HARDWARE,
146   MCE_INITIATOR_CPU,  MCE_SEV_SEVERE, true },
147 { 0x00000000001c0000, 0x0000000000080000, true,
148   MCE_ERROR_TYPE_SLB, MCE_SLB_ERROR_PARITY, MCE_ECLASS_HARD_INDETERMINATE,
149   MCE_INITIATOR_CPU,  MCE_SEV_SEVERE, true },
150 { 0x00000000001c0000, 0x00000000000c0000, true,
151   MCE_ERROR_TYPE_SLB, MCE_SLB_ERROR_MULTIHIT, MCE_ECLASS_SOFT_INDETERMINATE,
152   MCE_INITIATOR_CPU,  MCE_SEV_WARNING, true },
153 { 0x00000000001c0000, 0x0000000000100000, true,
154   MCE_ERROR_TYPE_SLB, MCE_SLB_ERROR_INDETERMINATE, /* BOTH */
155   MCE_ECLASS_SOFT_INDETERMINATE,
156   MCE_INITIATOR_CPU,  MCE_SEV_WARNING, true },
157 { 0x00000000001c0000, 0x0000000000140000, true,
158   MCE_ERROR_TYPE_TLB, MCE_TLB_ERROR_MULTIHIT, MCE_ECLASS_SOFT_INDETERMINATE,
159   MCE_INITIATOR_CPU,  MCE_SEV_WARNING, true },
160 { 0x00000000001c0000, 0x0000000000180000, true,
161   MCE_ERROR_TYPE_UE,  MCE_UE_ERROR_PAGE_TABLE_WALK_IFETCH, MCE_ECLASS_HARDWARE,
162   MCE_INITIATOR_CPU,  MCE_SEV_SEVERE, true },
163 { 0x00000000001c0000, 0x00000000001c0000, true,
164   MCE_ERROR_TYPE_UE,  MCE_UE_ERROR_IFETCH, MCE_ECLASS_HARDWARE,
165   MCE_INITIATOR_CPU,  MCE_SEV_SEVERE, true },
166 { 0, 0, 0, 0, 0, 0, 0 } };
167 
168 static const struct mce_ierror_table mce_p8_ierror_table[] = {
169 { 0x00000000081c0000, 0x0000000000040000, true,
170   MCE_ERROR_TYPE_UE,  MCE_UE_ERROR_IFETCH, MCE_ECLASS_HARDWARE,
171   MCE_INITIATOR_CPU,  MCE_SEV_SEVERE, true },
172 { 0x00000000081c0000, 0x0000000000080000, true,
173   MCE_ERROR_TYPE_SLB, MCE_SLB_ERROR_PARITY, MCE_ECLASS_HARD_INDETERMINATE,
174   MCE_INITIATOR_CPU,  MCE_SEV_SEVERE, true },
175 { 0x00000000081c0000, 0x00000000000c0000, true,
176   MCE_ERROR_TYPE_SLB, MCE_SLB_ERROR_MULTIHIT, MCE_ECLASS_SOFT_INDETERMINATE,
177   MCE_INITIATOR_CPU,  MCE_SEV_WARNING, true },
178 { 0x00000000081c0000, 0x0000000000100000, true,
179   MCE_ERROR_TYPE_ERAT, MCE_ERAT_ERROR_MULTIHIT, MCE_ECLASS_SOFT_INDETERMINATE,
180   MCE_INITIATOR_CPU,  MCE_SEV_WARNING, true },
181 { 0x00000000081c0000, 0x0000000000140000, true,
182   MCE_ERROR_TYPE_TLB, MCE_TLB_ERROR_MULTIHIT, MCE_ECLASS_SOFT_INDETERMINATE,
183   MCE_INITIATOR_CPU,  MCE_SEV_WARNING, true },
184 { 0x00000000081c0000, 0x0000000000180000, true,
185   MCE_ERROR_TYPE_UE,  MCE_UE_ERROR_PAGE_TABLE_WALK_IFETCH,
186   MCE_ECLASS_HARDWARE,
187   MCE_INITIATOR_CPU,  MCE_SEV_SEVERE, true },
188 { 0x00000000081c0000, 0x00000000001c0000, true,
189   MCE_ERROR_TYPE_UE,  MCE_UE_ERROR_IFETCH, MCE_ECLASS_HARDWARE,
190   MCE_INITIATOR_CPU,  MCE_SEV_SEVERE, true },
191 { 0x00000000081c0000, 0x0000000008000000, true,
192   MCE_ERROR_TYPE_LINK, MCE_LINK_ERROR_IFETCH_TIMEOUT, MCE_ECLASS_HARDWARE,
193   MCE_INITIATOR_CPU,  MCE_SEV_SEVERE, true },
194 { 0x00000000081c0000, 0x0000000008040000, true,
195   MCE_ERROR_TYPE_LINK,MCE_LINK_ERROR_PAGE_TABLE_WALK_IFETCH_TIMEOUT,
196   MCE_ECLASS_HARDWARE,
197   MCE_INITIATOR_CPU,  MCE_SEV_SEVERE, true },
198 { 0, 0, 0, 0, 0, 0, 0 } };
199 
200 static const struct mce_ierror_table mce_p9_ierror_table[] = {
201 { 0x00000000081c0000, 0x0000000000040000, true,
202   MCE_ERROR_TYPE_UE,  MCE_UE_ERROR_IFETCH, MCE_ECLASS_HARDWARE,
203   MCE_INITIATOR_CPU,  MCE_SEV_SEVERE, true },
204 { 0x00000000081c0000, 0x0000000000080000, true,
205   MCE_ERROR_TYPE_SLB, MCE_SLB_ERROR_PARITY, MCE_ECLASS_HARD_INDETERMINATE,
206   MCE_INITIATOR_CPU,  MCE_SEV_SEVERE, true },
207 { 0x00000000081c0000, 0x00000000000c0000, true,
208   MCE_ERROR_TYPE_SLB, MCE_SLB_ERROR_MULTIHIT, MCE_ECLASS_SOFT_INDETERMINATE,
209   MCE_INITIATOR_CPU,  MCE_SEV_WARNING, true },
210 { 0x00000000081c0000, 0x0000000000100000, true,
211   MCE_ERROR_TYPE_ERAT, MCE_ERAT_ERROR_MULTIHIT, MCE_ECLASS_SOFT_INDETERMINATE,
212   MCE_INITIATOR_CPU,  MCE_SEV_WARNING, true },
213 { 0x00000000081c0000, 0x0000000000140000, true,
214   MCE_ERROR_TYPE_TLB, MCE_TLB_ERROR_MULTIHIT, MCE_ECLASS_SOFT_INDETERMINATE,
215   MCE_INITIATOR_CPU,  MCE_SEV_WARNING, true },
216 { 0x00000000081c0000, 0x0000000000180000, true,
217   MCE_ERROR_TYPE_UE,  MCE_UE_ERROR_PAGE_TABLE_WALK_IFETCH, MCE_ECLASS_HARDWARE,
218   MCE_INITIATOR_CPU,  MCE_SEV_SEVERE, true },
219 { 0x00000000081c0000, 0x00000000001c0000, true,
220   MCE_ERROR_TYPE_RA,  MCE_RA_ERROR_IFETCH_FOREIGN, MCE_ECLASS_SOFTWARE,
221   MCE_INITIATOR_CPU,  MCE_SEV_SEVERE, true },
222 { 0x00000000081c0000, 0x0000000008000000, true,
223   MCE_ERROR_TYPE_LINK, MCE_LINK_ERROR_IFETCH_TIMEOUT, MCE_ECLASS_HARDWARE,
224   MCE_INITIATOR_CPU,  MCE_SEV_SEVERE, true },
225 { 0x00000000081c0000, 0x0000000008040000, true,
226   MCE_ERROR_TYPE_LINK,MCE_LINK_ERROR_PAGE_TABLE_WALK_IFETCH_TIMEOUT,
227   MCE_ECLASS_HARDWARE,
228   MCE_INITIATOR_CPU,  MCE_SEV_SEVERE, true },
229 { 0x00000000081c0000, 0x00000000080c0000, true,
230   MCE_ERROR_TYPE_RA,  MCE_RA_ERROR_IFETCH, MCE_ECLASS_SOFTWARE,
231   MCE_INITIATOR_CPU,  MCE_SEV_SEVERE, true },
232 { 0x00000000081c0000, 0x0000000008100000, true,
233   MCE_ERROR_TYPE_RA,  MCE_RA_ERROR_PAGE_TABLE_WALK_IFETCH, MCE_ECLASS_SOFTWARE,
234   MCE_INITIATOR_CPU,  MCE_SEV_SEVERE, true },
235 { 0x00000000081c0000, 0x0000000008140000, false,
236   MCE_ERROR_TYPE_RA,  MCE_RA_ERROR_STORE, MCE_ECLASS_HARDWARE,
237   MCE_INITIATOR_CPU,  MCE_SEV_FATAL, false }, /* ASYNC is fatal */
238 { 0x00000000081c0000, 0x0000000008180000, false,
239   MCE_ERROR_TYPE_LINK,MCE_LINK_ERROR_STORE_TIMEOUT,
240   MCE_INITIATOR_CPU,  MCE_SEV_FATAL, false }, /* ASYNC is fatal */
241 { 0x00000000081c0000, 0x00000000081c0000, true, MCE_ECLASS_HARDWARE,
242   MCE_ERROR_TYPE_RA,  MCE_RA_ERROR_PAGE_TABLE_WALK_IFETCH_FOREIGN,
243   MCE_INITIATOR_CPU,  MCE_SEV_SEVERE, true },
244 { 0, 0, 0, 0, 0, 0, 0 } };
245 
246 struct mce_derror_table {
247 	unsigned long dsisr_value;
248 	bool dar_valid; /* dar is a valid indicator of faulting address */
249 	unsigned int error_type;
250 	unsigned int error_subtype;
251 	unsigned int error_class;
252 	unsigned int initiator;
253 	unsigned int severity;
254 	bool sync_error;
255 };
256 
257 static const struct mce_derror_table mce_p7_derror_table[] = {
258 { 0x00008000, false,
259   MCE_ERROR_TYPE_UE,   MCE_UE_ERROR_LOAD_STORE, MCE_ECLASS_HARDWARE,
260   MCE_INITIATOR_CPU,   MCE_SEV_SEVERE, true },
261 { 0x00004000, true,
262   MCE_ERROR_TYPE_UE,   MCE_UE_ERROR_PAGE_TABLE_WALK_LOAD_STORE,
263   MCE_ECLASS_HARDWARE,
264   MCE_INITIATOR_CPU,   MCE_SEV_SEVERE, true },
265 { 0x00000800, true,
266   MCE_ERROR_TYPE_ERAT, MCE_ERAT_ERROR_MULTIHIT, MCE_ECLASS_SOFT_INDETERMINATE,
267   MCE_INITIATOR_CPU,   MCE_SEV_WARNING, true },
268 { 0x00000400, true,
269   MCE_ERROR_TYPE_TLB,  MCE_TLB_ERROR_MULTIHIT, MCE_ECLASS_SOFT_INDETERMINATE,
270   MCE_INITIATOR_CPU,   MCE_SEV_WARNING, true },
271 { 0x00000080, true,
272   MCE_ERROR_TYPE_SLB,  MCE_SLB_ERROR_MULTIHIT, MCE_ECLASS_SOFT_INDETERMINATE,
273   MCE_INITIATOR_CPU,   MCE_SEV_WARNING, true },
274 { 0x00000100, true,
275   MCE_ERROR_TYPE_SLB,  MCE_SLB_ERROR_PARITY, MCE_ECLASS_HARD_INDETERMINATE,
276   MCE_INITIATOR_CPU,   MCE_SEV_SEVERE, true },
277 { 0x00000040, true,
278   MCE_ERROR_TYPE_SLB,  MCE_SLB_ERROR_INDETERMINATE, /* BOTH */
279   MCE_ECLASS_HARD_INDETERMINATE,
280   MCE_INITIATOR_CPU,   MCE_SEV_WARNING, true },
281 { 0, false, 0, 0, 0, 0, 0 } };
282 
283 static const struct mce_derror_table mce_p8_derror_table[] = {
284 { 0x00008000, false,
285   MCE_ERROR_TYPE_UE,   MCE_UE_ERROR_LOAD_STORE, MCE_ECLASS_HARDWARE,
286   MCE_INITIATOR_CPU,   MCE_SEV_SEVERE, true },
287 { 0x00004000, true,
288   MCE_ERROR_TYPE_UE,   MCE_UE_ERROR_PAGE_TABLE_WALK_LOAD_STORE,
289   MCE_ECLASS_HARDWARE,
290   MCE_INITIATOR_CPU,   MCE_SEV_SEVERE, true },
291 { 0x00002000, true,
292   MCE_ERROR_TYPE_LINK, MCE_LINK_ERROR_LOAD_TIMEOUT, MCE_ECLASS_HARDWARE,
293   MCE_INITIATOR_CPU,   MCE_SEV_SEVERE, true },
294 { 0x00001000, true,
295   MCE_ERROR_TYPE_LINK, MCE_LINK_ERROR_PAGE_TABLE_WALK_LOAD_STORE_TIMEOUT,
296   MCE_ECLASS_HARDWARE,
297   MCE_INITIATOR_CPU,   MCE_SEV_SEVERE, true },
298 { 0x00000800, true,
299   MCE_ERROR_TYPE_ERAT, MCE_ERAT_ERROR_MULTIHIT, MCE_ECLASS_SOFT_INDETERMINATE,
300   MCE_INITIATOR_CPU,   MCE_SEV_WARNING, true },
301 { 0x00000400, true,
302   MCE_ERROR_TYPE_TLB,  MCE_TLB_ERROR_MULTIHIT, MCE_ECLASS_SOFT_INDETERMINATE,
303   MCE_INITIATOR_CPU,   MCE_SEV_WARNING, true },
304 { 0x00000200, true,
305   MCE_ERROR_TYPE_ERAT, MCE_ERAT_ERROR_MULTIHIT, /* SECONDARY ERAT */
306   MCE_ECLASS_SOFT_INDETERMINATE,
307   MCE_INITIATOR_CPU,   MCE_SEV_WARNING, true },
308 { 0x00000080, true,
309   MCE_ERROR_TYPE_SLB,  MCE_SLB_ERROR_MULTIHIT,	/* Before PARITY */
310   MCE_ECLASS_SOFT_INDETERMINATE,
311   MCE_INITIATOR_CPU,   MCE_SEV_WARNING, true },
312 { 0x00000100, true,
313   MCE_ERROR_TYPE_SLB,  MCE_SLB_ERROR_PARITY, MCE_ECLASS_HARD_INDETERMINATE,
314   MCE_INITIATOR_CPU,   MCE_SEV_SEVERE, true },
315 { 0, false, 0, 0, 0, 0, 0 } };
316 
317 static const struct mce_derror_table mce_p9_derror_table[] = {
318 { 0x00008000, false,
319   MCE_ERROR_TYPE_UE,   MCE_UE_ERROR_LOAD_STORE, MCE_ECLASS_HARDWARE,
320   MCE_INITIATOR_CPU,   MCE_SEV_SEVERE, true },
321 { 0x00004000, true,
322   MCE_ERROR_TYPE_UE,   MCE_UE_ERROR_PAGE_TABLE_WALK_LOAD_STORE,
323   MCE_ECLASS_HARDWARE,
324   MCE_INITIATOR_CPU,   MCE_SEV_SEVERE, true },
325 { 0x00002000, true,
326   MCE_ERROR_TYPE_LINK, MCE_LINK_ERROR_LOAD_TIMEOUT, MCE_ECLASS_HARDWARE,
327   MCE_INITIATOR_CPU,   MCE_SEV_SEVERE, true },
328 { 0x00001000, true,
329   MCE_ERROR_TYPE_LINK, MCE_LINK_ERROR_PAGE_TABLE_WALK_LOAD_STORE_TIMEOUT,
330   MCE_ECLASS_HARDWARE,
331   MCE_INITIATOR_CPU,   MCE_SEV_SEVERE, true },
332 { 0x00000800, true,
333   MCE_ERROR_TYPE_ERAT, MCE_ERAT_ERROR_MULTIHIT, MCE_ECLASS_SOFT_INDETERMINATE,
334   MCE_INITIATOR_CPU,   MCE_SEV_WARNING, true },
335 { 0x00000400, true,
336   MCE_ERROR_TYPE_TLB,  MCE_TLB_ERROR_MULTIHIT, MCE_ECLASS_SOFT_INDETERMINATE,
337   MCE_INITIATOR_CPU,   MCE_SEV_WARNING, true },
338 { 0x00000200, false,
339   MCE_ERROR_TYPE_USER, MCE_USER_ERROR_TLBIE, MCE_ECLASS_SOFTWARE,
340   MCE_INITIATOR_CPU,   MCE_SEV_WARNING, true },
341 { 0x00000080, true,
342   MCE_ERROR_TYPE_SLB,  MCE_SLB_ERROR_MULTIHIT,	/* Before PARITY */
343   MCE_ECLASS_SOFT_INDETERMINATE,
344   MCE_INITIATOR_CPU,   MCE_SEV_WARNING, true },
345 { 0x00000100, true,
346   MCE_ERROR_TYPE_SLB,  MCE_SLB_ERROR_PARITY, MCE_ECLASS_HARD_INDETERMINATE,
347   MCE_INITIATOR_CPU,   MCE_SEV_SEVERE, true },
348 { 0x00000040, true,
349   MCE_ERROR_TYPE_RA,   MCE_RA_ERROR_LOAD, MCE_ECLASS_HARDWARE,
350   MCE_INITIATOR_CPU,   MCE_SEV_SEVERE, true },
351 { 0x00000020, false,
352   MCE_ERROR_TYPE_RA,   MCE_RA_ERROR_PAGE_TABLE_WALK_LOAD_STORE,
353   MCE_ECLASS_HARDWARE,
354   MCE_INITIATOR_CPU,   MCE_SEV_SEVERE, true },
355 { 0x00000010, false,
356   MCE_ERROR_TYPE_RA,   MCE_RA_ERROR_PAGE_TABLE_WALK_LOAD_STORE_FOREIGN,
357   MCE_ECLASS_HARDWARE,
358   MCE_INITIATOR_CPU,   MCE_SEV_SEVERE, true },
359 { 0x00000008, false,
360   MCE_ERROR_TYPE_RA,   MCE_RA_ERROR_LOAD_STORE_FOREIGN, MCE_ECLASS_HARDWARE,
361   MCE_INITIATOR_CPU,   MCE_SEV_SEVERE, true },
362 { 0, false, 0, 0, 0, 0, 0 } };
363 
364 static int mce_find_instr_ea_and_phys(struct pt_regs *regs, uint64_t *addr,
365 					uint64_t *phys_addr)
366 {
367 	/*
368 	 * Carefully look at the NIP to determine
369 	 * the instruction to analyse. Reading the NIP
370 	 * in real-mode is tricky and can lead to recursive
371 	 * faults
372 	 */
373 	struct ppc_inst instr;
374 	unsigned long pfn, instr_addr;
375 	struct instruction_op op;
376 	struct pt_regs tmp = *regs;
377 
378 	pfn = addr_to_pfn(regs, regs->nip);
379 	if (pfn != ULONG_MAX) {
380 		instr_addr = (pfn << PAGE_SHIFT) + (regs->nip & ~PAGE_MASK);
381 		instr = ppc_inst_read((struct ppc_inst *)instr_addr);
382 		if (!analyse_instr(&op, &tmp, instr)) {
383 			pfn = addr_to_pfn(regs, op.ea);
384 			*addr = op.ea;
385 			*phys_addr = (pfn << PAGE_SHIFT);
386 			return 0;
387 		}
388 		/*
389 		 * analyse_instr() might fail if the instruction
390 		 * is not a load/store, although this is unexpected
391 		 * for load/store errors or if we got the NIP
392 		 * wrong
393 		 */
394 	}
395 	*addr = 0;
396 	return -1;
397 }
398 
399 static int mce_handle_ierror(struct pt_regs *regs,
400 		const struct mce_ierror_table table[],
401 		struct mce_error_info *mce_err, uint64_t *addr,
402 		uint64_t *phys_addr)
403 {
404 	uint64_t srr1 = regs->msr;
405 	int handled = 0;
406 	int i;
407 
408 	*addr = 0;
409 
410 	for (i = 0; table[i].srr1_mask; i++) {
411 		if ((srr1 & table[i].srr1_mask) != table[i].srr1_value)
412 			continue;
413 
414 		/* attempt to correct the error */
415 		switch (table[i].error_type) {
416 		case MCE_ERROR_TYPE_SLB:
417 			if (local_paca->in_mce == 1)
418 				slb_save_contents(local_paca->mce_faulty_slbs);
419 			handled = mce_flush(MCE_FLUSH_SLB);
420 			break;
421 		case MCE_ERROR_TYPE_ERAT:
422 			handled = mce_flush(MCE_FLUSH_ERAT);
423 			break;
424 		case MCE_ERROR_TYPE_TLB:
425 			handled = mce_flush(MCE_FLUSH_TLB);
426 			break;
427 		}
428 
429 		/* now fill in mce_error_info */
430 		mce_err->error_type = table[i].error_type;
431 		mce_err->error_class = table[i].error_class;
432 		switch (table[i].error_type) {
433 		case MCE_ERROR_TYPE_UE:
434 			mce_err->u.ue_error_type = table[i].error_subtype;
435 			break;
436 		case MCE_ERROR_TYPE_SLB:
437 			mce_err->u.slb_error_type = table[i].error_subtype;
438 			break;
439 		case MCE_ERROR_TYPE_ERAT:
440 			mce_err->u.erat_error_type = table[i].error_subtype;
441 			break;
442 		case MCE_ERROR_TYPE_TLB:
443 			mce_err->u.tlb_error_type = table[i].error_subtype;
444 			break;
445 		case MCE_ERROR_TYPE_USER:
446 			mce_err->u.user_error_type = table[i].error_subtype;
447 			break;
448 		case MCE_ERROR_TYPE_RA:
449 			mce_err->u.ra_error_type = table[i].error_subtype;
450 			break;
451 		case MCE_ERROR_TYPE_LINK:
452 			mce_err->u.link_error_type = table[i].error_subtype;
453 			break;
454 		}
455 		mce_err->sync_error = table[i].sync_error;
456 		mce_err->severity = table[i].severity;
457 		mce_err->initiator = table[i].initiator;
458 		if (table[i].nip_valid) {
459 			*addr = regs->nip;
460 			if (mce_err->sync_error &&
461 				table[i].error_type == MCE_ERROR_TYPE_UE) {
462 				unsigned long pfn;
463 
464 				if (get_paca()->in_mce < MAX_MCE_DEPTH) {
465 					pfn = addr_to_pfn(regs, regs->nip);
466 					if (pfn != ULONG_MAX) {
467 						*phys_addr =
468 							(pfn << PAGE_SHIFT);
469 					}
470 				}
471 			}
472 		}
473 		return handled;
474 	}
475 
476 	mce_err->error_type = MCE_ERROR_TYPE_UNKNOWN;
477 	mce_err->error_class = MCE_ECLASS_UNKNOWN;
478 	mce_err->severity = MCE_SEV_SEVERE;
479 	mce_err->initiator = MCE_INITIATOR_CPU;
480 	mce_err->sync_error = true;
481 
482 	return 0;
483 }
484 
485 static int mce_handle_derror(struct pt_regs *regs,
486 		const struct mce_derror_table table[],
487 		struct mce_error_info *mce_err, uint64_t *addr,
488 		uint64_t *phys_addr)
489 {
490 	uint64_t dsisr = regs->dsisr;
491 	int handled = 0;
492 	int found = 0;
493 	int i;
494 
495 	*addr = 0;
496 
497 	for (i = 0; table[i].dsisr_value; i++) {
498 		if (!(dsisr & table[i].dsisr_value))
499 			continue;
500 
501 		/* attempt to correct the error */
502 		switch (table[i].error_type) {
503 		case MCE_ERROR_TYPE_SLB:
504 			if (local_paca->in_mce == 1)
505 				slb_save_contents(local_paca->mce_faulty_slbs);
506 			if (mce_flush(MCE_FLUSH_SLB))
507 				handled = 1;
508 			break;
509 		case MCE_ERROR_TYPE_ERAT:
510 			if (mce_flush(MCE_FLUSH_ERAT))
511 				handled = 1;
512 			break;
513 		case MCE_ERROR_TYPE_TLB:
514 			if (mce_flush(MCE_FLUSH_TLB))
515 				handled = 1;
516 			break;
517 		}
518 
519 		/*
520 		 * Attempt to handle multiple conditions, but only return
521 		 * one. Ensure uncorrectable errors are first in the table
522 		 * to match.
523 		 */
524 		if (found)
525 			continue;
526 
527 		/* now fill in mce_error_info */
528 		mce_err->error_type = table[i].error_type;
529 		mce_err->error_class = table[i].error_class;
530 		switch (table[i].error_type) {
531 		case MCE_ERROR_TYPE_UE:
532 			mce_err->u.ue_error_type = table[i].error_subtype;
533 			break;
534 		case MCE_ERROR_TYPE_SLB:
535 			mce_err->u.slb_error_type = table[i].error_subtype;
536 			break;
537 		case MCE_ERROR_TYPE_ERAT:
538 			mce_err->u.erat_error_type = table[i].error_subtype;
539 			break;
540 		case MCE_ERROR_TYPE_TLB:
541 			mce_err->u.tlb_error_type = table[i].error_subtype;
542 			break;
543 		case MCE_ERROR_TYPE_USER:
544 			mce_err->u.user_error_type = table[i].error_subtype;
545 			break;
546 		case MCE_ERROR_TYPE_RA:
547 			mce_err->u.ra_error_type = table[i].error_subtype;
548 			break;
549 		case MCE_ERROR_TYPE_LINK:
550 			mce_err->u.link_error_type = table[i].error_subtype;
551 			break;
552 		}
553 		mce_err->sync_error = table[i].sync_error;
554 		mce_err->severity = table[i].severity;
555 		mce_err->initiator = table[i].initiator;
556 		if (table[i].dar_valid)
557 			*addr = regs->dar;
558 		else if (mce_err->sync_error &&
559 				table[i].error_type == MCE_ERROR_TYPE_UE) {
560 			/*
561 			 * We do a maximum of 4 nested MCE calls, see
562 			 * kernel/exception-64s.h
563 			 */
564 			if (get_paca()->in_mce < MAX_MCE_DEPTH)
565 				mce_find_instr_ea_and_phys(regs, addr,
566 							   phys_addr);
567 		}
568 		found = 1;
569 	}
570 
571 	if (found)
572 		return handled;
573 
574 	mce_err->error_type = MCE_ERROR_TYPE_UNKNOWN;
575 	mce_err->error_class = MCE_ECLASS_UNKNOWN;
576 	mce_err->severity = MCE_SEV_SEVERE;
577 	mce_err->initiator = MCE_INITIATOR_CPU;
578 	mce_err->sync_error = true;
579 
580 	return 0;
581 }
582 
583 static long mce_handle_ue_error(struct pt_regs *regs,
584 				struct mce_error_info *mce_err)
585 {
586 	long handled = 0;
587 
588 	mce_common_process_ue(regs, mce_err);
589 	if (mce_err->ignore_event)
590 		return 1;
591 
592 	/*
593 	 * On specific SCOM read via MMIO we may get a machine check
594 	 * exception with SRR0 pointing inside opal. If that is the
595 	 * case OPAL may have recovery address to re-read SCOM data in
596 	 * different way and hence we can recover from this MC.
597 	 */
598 
599 	if (ppc_md.mce_check_early_recovery) {
600 		if (ppc_md.mce_check_early_recovery(regs))
601 			handled = 1;
602 	}
603 	return handled;
604 }
605 
606 static long mce_handle_error(struct pt_regs *regs,
607 		const struct mce_derror_table dtable[],
608 		const struct mce_ierror_table itable[])
609 {
610 	struct mce_error_info mce_err = { 0 };
611 	uint64_t addr, phys_addr = ULONG_MAX;
612 	uint64_t srr1 = regs->msr;
613 	long handled;
614 
615 	if (SRR1_MC_LOADSTORE(srr1))
616 		handled = mce_handle_derror(regs, dtable, &mce_err, &addr,
617 				&phys_addr);
618 	else
619 		handled = mce_handle_ierror(regs, itable, &mce_err, &addr,
620 				&phys_addr);
621 
622 	if (!handled && mce_err.error_type == MCE_ERROR_TYPE_UE)
623 		handled = mce_handle_ue_error(regs, &mce_err);
624 
625 	save_mce_event(regs, handled, &mce_err, regs->nip, addr, phys_addr);
626 
627 	return handled;
628 }
629 
630 long __machine_check_early_realmode_p7(struct pt_regs *regs)
631 {
632 	/* P7 DD1 leaves top bits of DSISR undefined */
633 	regs->dsisr &= 0x0000ffff;
634 
635 	return mce_handle_error(regs, mce_p7_derror_table, mce_p7_ierror_table);
636 }
637 
638 long __machine_check_early_realmode_p8(struct pt_regs *regs)
639 {
640 	return mce_handle_error(regs, mce_p8_derror_table, mce_p8_ierror_table);
641 }
642 
643 long __machine_check_early_realmode_p9(struct pt_regs *regs)
644 {
645 	/*
646 	 * On POWER9 DD2.1 and below, it's possible to get a machine check
647 	 * caused by a paste instruction where only DSISR bit 25 is set. This
648 	 * will result in the MCE handler seeing an unknown event and the kernel
649 	 * crashing. An MCE that occurs like this is spurious, so we don't need
650 	 * to do anything in terms of servicing it. If there is something that
651 	 * needs to be serviced, the CPU will raise the MCE again with the
652 	 * correct DSISR so that it can be serviced properly. So detect this
653 	 * case and mark it as handled.
654 	 */
655 	if (SRR1_MC_LOADSTORE(regs->msr) && regs->dsisr == 0x02000000)
656 		return 1;
657 
658 	return mce_handle_error(regs, mce_p9_derror_table, mce_p9_ierror_table);
659 }
660