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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  */
addr_to_pfn(struct pt_regs * regs,unsigned long addr)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
flush_and_reload_slb(void)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 
flush_erat(void)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 
mce_flush(int what)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 static const struct mce_ierror_table mce_p10_ierror_table[] = {
247 { 0x00000000081c0000, 0x0000000000040000, true,
248   MCE_ERROR_TYPE_UE,  MCE_UE_ERROR_IFETCH, MCE_ECLASS_HARDWARE,
249   MCE_INITIATOR_CPU,  MCE_SEV_SEVERE, true },
250 { 0x00000000081c0000, 0x0000000000080000, true,
251   MCE_ERROR_TYPE_SLB, MCE_SLB_ERROR_PARITY, MCE_ECLASS_HARD_INDETERMINATE,
252   MCE_INITIATOR_CPU,  MCE_SEV_SEVERE, true },
253 { 0x00000000081c0000, 0x00000000000c0000, true,
254   MCE_ERROR_TYPE_SLB, MCE_SLB_ERROR_MULTIHIT, MCE_ECLASS_SOFT_INDETERMINATE,
255   MCE_INITIATOR_CPU,  MCE_SEV_WARNING, true },
256 { 0x00000000081c0000, 0x0000000000100000, true,
257   MCE_ERROR_TYPE_ERAT, MCE_ERAT_ERROR_MULTIHIT, MCE_ECLASS_SOFT_INDETERMINATE,
258   MCE_INITIATOR_CPU,  MCE_SEV_WARNING, true },
259 { 0x00000000081c0000, 0x0000000000140000, true,
260   MCE_ERROR_TYPE_TLB, MCE_TLB_ERROR_MULTIHIT, MCE_ECLASS_SOFT_INDETERMINATE,
261   MCE_INITIATOR_CPU,  MCE_SEV_WARNING, true },
262 { 0x00000000081c0000, 0x0000000000180000, true,
263   MCE_ERROR_TYPE_UE,  MCE_UE_ERROR_PAGE_TABLE_WALK_IFETCH, MCE_ECLASS_HARDWARE,
264   MCE_INITIATOR_CPU,  MCE_SEV_SEVERE, true },
265 { 0x00000000081c0000, 0x00000000001c0000, true,
266   MCE_ERROR_TYPE_RA,  MCE_RA_ERROR_IFETCH_FOREIGN, MCE_ECLASS_SOFTWARE,
267   MCE_INITIATOR_CPU,  MCE_SEV_SEVERE, true },
268 { 0x00000000081c0000, 0x0000000008080000, true,
269   MCE_ERROR_TYPE_USER,MCE_USER_ERROR_SCV, MCE_ECLASS_SOFTWARE,
270   MCE_INITIATOR_CPU,  MCE_SEV_WARNING, true },
271 { 0x00000000081c0000, 0x00000000080c0000, true,
272   MCE_ERROR_TYPE_RA,  MCE_RA_ERROR_IFETCH, MCE_ECLASS_SOFTWARE,
273   MCE_INITIATOR_CPU,  MCE_SEV_SEVERE, true },
274 { 0x00000000081c0000, 0x0000000008100000, true,
275   MCE_ERROR_TYPE_RA,  MCE_RA_ERROR_PAGE_TABLE_WALK_IFETCH, MCE_ECLASS_SOFTWARE,
276   MCE_INITIATOR_CPU,  MCE_SEV_SEVERE, true },
277 { 0x00000000081c0000, 0x0000000008140000, false,
278   MCE_ERROR_TYPE_RA,  MCE_RA_ERROR_STORE, MCE_ECLASS_HARDWARE,
279   MCE_INITIATOR_CPU,  MCE_SEV_FATAL, false }, /* ASYNC is fatal */
280 { 0x00000000081c0000, 0x00000000081c0000, true, MCE_ECLASS_HARDWARE,
281   MCE_ERROR_TYPE_RA,  MCE_RA_ERROR_PAGE_TABLE_WALK_IFETCH_FOREIGN,
282   MCE_INITIATOR_CPU,  MCE_SEV_SEVERE, true },
283 { 0, 0, 0, 0, 0, 0, 0 } };
284 
285 struct mce_derror_table {
286 	unsigned long dsisr_value;
287 	bool dar_valid; /* dar is a valid indicator of faulting address */
288 	unsigned int error_type;
289 	unsigned int error_subtype;
290 	unsigned int error_class;
291 	unsigned int initiator;
292 	unsigned int severity;
293 	bool sync_error;
294 };
295 
296 static const struct mce_derror_table mce_p7_derror_table[] = {
297 { 0x00008000, false,
298   MCE_ERROR_TYPE_UE,   MCE_UE_ERROR_LOAD_STORE, MCE_ECLASS_HARDWARE,
299   MCE_INITIATOR_CPU,   MCE_SEV_SEVERE, true },
300 { 0x00004000, true,
301   MCE_ERROR_TYPE_UE,   MCE_UE_ERROR_PAGE_TABLE_WALK_LOAD_STORE,
302   MCE_ECLASS_HARDWARE,
303   MCE_INITIATOR_CPU,   MCE_SEV_SEVERE, true },
304 { 0x00000800, true,
305   MCE_ERROR_TYPE_ERAT, MCE_ERAT_ERROR_MULTIHIT, MCE_ECLASS_SOFT_INDETERMINATE,
306   MCE_INITIATOR_CPU,   MCE_SEV_WARNING, true },
307 { 0x00000400, true,
308   MCE_ERROR_TYPE_TLB,  MCE_TLB_ERROR_MULTIHIT, MCE_ECLASS_SOFT_INDETERMINATE,
309   MCE_INITIATOR_CPU,   MCE_SEV_WARNING, true },
310 { 0x00000080, true,
311   MCE_ERROR_TYPE_SLB,  MCE_SLB_ERROR_MULTIHIT, MCE_ECLASS_SOFT_INDETERMINATE,
312   MCE_INITIATOR_CPU,   MCE_SEV_WARNING, true },
313 { 0x00000100, true,
314   MCE_ERROR_TYPE_SLB,  MCE_SLB_ERROR_PARITY, MCE_ECLASS_HARD_INDETERMINATE,
315   MCE_INITIATOR_CPU,   MCE_SEV_SEVERE, true },
316 { 0x00000040, true,
317   MCE_ERROR_TYPE_SLB,  MCE_SLB_ERROR_INDETERMINATE, /* BOTH */
318   MCE_ECLASS_HARD_INDETERMINATE,
319   MCE_INITIATOR_CPU,   MCE_SEV_WARNING, true },
320 { 0, false, 0, 0, 0, 0, 0 } };
321 
322 static const struct mce_derror_table mce_p8_derror_table[] = {
323 { 0x00008000, false,
324   MCE_ERROR_TYPE_UE,   MCE_UE_ERROR_LOAD_STORE, MCE_ECLASS_HARDWARE,
325   MCE_INITIATOR_CPU,   MCE_SEV_SEVERE, true },
326 { 0x00004000, true,
327   MCE_ERROR_TYPE_UE,   MCE_UE_ERROR_PAGE_TABLE_WALK_LOAD_STORE,
328   MCE_ECLASS_HARDWARE,
329   MCE_INITIATOR_CPU,   MCE_SEV_SEVERE, true },
330 { 0x00002000, true,
331   MCE_ERROR_TYPE_LINK, MCE_LINK_ERROR_LOAD_TIMEOUT, MCE_ECLASS_HARDWARE,
332   MCE_INITIATOR_CPU,   MCE_SEV_SEVERE, true },
333 { 0x00001000, true,
334   MCE_ERROR_TYPE_LINK, MCE_LINK_ERROR_PAGE_TABLE_WALK_LOAD_STORE_TIMEOUT,
335   MCE_ECLASS_HARDWARE,
336   MCE_INITIATOR_CPU,   MCE_SEV_SEVERE, true },
337 { 0x00000800, true,
338   MCE_ERROR_TYPE_ERAT, MCE_ERAT_ERROR_MULTIHIT, MCE_ECLASS_SOFT_INDETERMINATE,
339   MCE_INITIATOR_CPU,   MCE_SEV_WARNING, true },
340 { 0x00000400, true,
341   MCE_ERROR_TYPE_TLB,  MCE_TLB_ERROR_MULTIHIT, MCE_ECLASS_SOFT_INDETERMINATE,
342   MCE_INITIATOR_CPU,   MCE_SEV_WARNING, true },
343 { 0x00000200, true,
344   MCE_ERROR_TYPE_ERAT, MCE_ERAT_ERROR_MULTIHIT, /* SECONDARY ERAT */
345   MCE_ECLASS_SOFT_INDETERMINATE,
346   MCE_INITIATOR_CPU,   MCE_SEV_WARNING, true },
347 { 0x00000080, true,
348   MCE_ERROR_TYPE_SLB,  MCE_SLB_ERROR_MULTIHIT,	/* Before PARITY */
349   MCE_ECLASS_SOFT_INDETERMINATE,
350   MCE_INITIATOR_CPU,   MCE_SEV_WARNING, true },
351 { 0x00000100, true,
352   MCE_ERROR_TYPE_SLB,  MCE_SLB_ERROR_PARITY, MCE_ECLASS_HARD_INDETERMINATE,
353   MCE_INITIATOR_CPU,   MCE_SEV_SEVERE, true },
354 { 0, false, 0, 0, 0, 0, 0 } };
355 
356 static const struct mce_derror_table mce_p9_derror_table[] = {
357 { 0x00008000, false,
358   MCE_ERROR_TYPE_UE,   MCE_UE_ERROR_LOAD_STORE, MCE_ECLASS_HARDWARE,
359   MCE_INITIATOR_CPU,   MCE_SEV_SEVERE, true },
360 { 0x00004000, true,
361   MCE_ERROR_TYPE_UE,   MCE_UE_ERROR_PAGE_TABLE_WALK_LOAD_STORE,
362   MCE_ECLASS_HARDWARE,
363   MCE_INITIATOR_CPU,   MCE_SEV_SEVERE, true },
364 { 0x00002000, true,
365   MCE_ERROR_TYPE_LINK, MCE_LINK_ERROR_LOAD_TIMEOUT, MCE_ECLASS_HARDWARE,
366   MCE_INITIATOR_CPU,   MCE_SEV_SEVERE, true },
367 { 0x00001000, true,
368   MCE_ERROR_TYPE_LINK, MCE_LINK_ERROR_PAGE_TABLE_WALK_LOAD_STORE_TIMEOUT,
369   MCE_ECLASS_HARDWARE,
370   MCE_INITIATOR_CPU,   MCE_SEV_SEVERE, true },
371 { 0x00000800, true,
372   MCE_ERROR_TYPE_ERAT, MCE_ERAT_ERROR_MULTIHIT, MCE_ECLASS_SOFT_INDETERMINATE,
373   MCE_INITIATOR_CPU,   MCE_SEV_WARNING, true },
374 { 0x00000400, true,
375   MCE_ERROR_TYPE_TLB,  MCE_TLB_ERROR_MULTIHIT, MCE_ECLASS_SOFT_INDETERMINATE,
376   MCE_INITIATOR_CPU,   MCE_SEV_WARNING, true },
377 { 0x00000200, false,
378   MCE_ERROR_TYPE_USER, MCE_USER_ERROR_TLBIE, MCE_ECLASS_SOFTWARE,
379   MCE_INITIATOR_CPU,   MCE_SEV_WARNING, true },
380 { 0x00000080, true,
381   MCE_ERROR_TYPE_SLB,  MCE_SLB_ERROR_MULTIHIT,	/* Before PARITY */
382   MCE_ECLASS_SOFT_INDETERMINATE,
383   MCE_INITIATOR_CPU,   MCE_SEV_WARNING, true },
384 { 0x00000100, true,
385   MCE_ERROR_TYPE_SLB,  MCE_SLB_ERROR_PARITY, MCE_ECLASS_HARD_INDETERMINATE,
386   MCE_INITIATOR_CPU,   MCE_SEV_SEVERE, true },
387 { 0x00000040, true,
388   MCE_ERROR_TYPE_RA,   MCE_RA_ERROR_LOAD, MCE_ECLASS_HARDWARE,
389   MCE_INITIATOR_CPU,   MCE_SEV_SEVERE, true },
390 { 0x00000020, false,
391   MCE_ERROR_TYPE_RA,   MCE_RA_ERROR_PAGE_TABLE_WALK_LOAD_STORE,
392   MCE_ECLASS_HARDWARE,
393   MCE_INITIATOR_CPU,   MCE_SEV_SEVERE, true },
394 { 0x00000010, false,
395   MCE_ERROR_TYPE_RA,   MCE_RA_ERROR_PAGE_TABLE_WALK_LOAD_STORE_FOREIGN,
396   MCE_ECLASS_HARDWARE,
397   MCE_INITIATOR_CPU,   MCE_SEV_SEVERE, true },
398 { 0x00000008, false,
399   MCE_ERROR_TYPE_RA,   MCE_RA_ERROR_LOAD_STORE_FOREIGN, MCE_ECLASS_HARDWARE,
400   MCE_INITIATOR_CPU,   MCE_SEV_SEVERE, true },
401 { 0, false, 0, 0, 0, 0, 0 } };
402 
403 static const struct mce_derror_table mce_p10_derror_table[] = {
404 { 0x00008000, false,
405   MCE_ERROR_TYPE_UE,   MCE_UE_ERROR_LOAD_STORE, MCE_ECLASS_HARDWARE,
406   MCE_INITIATOR_CPU,   MCE_SEV_SEVERE, true },
407 { 0x00004000, true,
408   MCE_ERROR_TYPE_UE,   MCE_UE_ERROR_PAGE_TABLE_WALK_LOAD_STORE,
409   MCE_ECLASS_HARDWARE,
410   MCE_INITIATOR_CPU,   MCE_SEV_SEVERE, true },
411 { 0x00000800, true,
412   MCE_ERROR_TYPE_ERAT, MCE_ERAT_ERROR_MULTIHIT, MCE_ECLASS_SOFT_INDETERMINATE,
413   MCE_INITIATOR_CPU,   MCE_SEV_WARNING, true },
414 { 0x00000400, true,
415   MCE_ERROR_TYPE_TLB,  MCE_TLB_ERROR_MULTIHIT, MCE_ECLASS_SOFT_INDETERMINATE,
416   MCE_INITIATOR_CPU,   MCE_SEV_WARNING, true },
417 { 0x00000200, false,
418   MCE_ERROR_TYPE_USER, MCE_USER_ERROR_TLBIE, MCE_ECLASS_SOFTWARE,
419   MCE_INITIATOR_CPU,   MCE_SEV_WARNING, true },
420 { 0x00000080, true,
421   MCE_ERROR_TYPE_SLB,  MCE_SLB_ERROR_MULTIHIT,	/* Before PARITY */
422   MCE_ECLASS_SOFT_INDETERMINATE,
423   MCE_INITIATOR_CPU,   MCE_SEV_WARNING, true },
424 { 0x00000100, true,
425   MCE_ERROR_TYPE_SLB,  MCE_SLB_ERROR_PARITY, MCE_ECLASS_HARD_INDETERMINATE,
426   MCE_INITIATOR_CPU,   MCE_SEV_SEVERE, true },
427 { 0x00000040, true,
428   MCE_ERROR_TYPE_RA,   MCE_RA_ERROR_LOAD, MCE_ECLASS_HARDWARE,
429   MCE_INITIATOR_CPU,   MCE_SEV_SEVERE, true },
430 { 0x00000020, false,
431   MCE_ERROR_TYPE_RA,   MCE_RA_ERROR_PAGE_TABLE_WALK_LOAD_STORE,
432   MCE_ECLASS_HARDWARE,
433   MCE_INITIATOR_CPU,   MCE_SEV_SEVERE, true },
434 { 0x00000010, false,
435   MCE_ERROR_TYPE_RA,   MCE_RA_ERROR_PAGE_TABLE_WALK_LOAD_STORE_FOREIGN,
436   MCE_ECLASS_HARDWARE,
437   MCE_INITIATOR_CPU,   MCE_SEV_SEVERE, true },
438 { 0x00000008, false,
439   MCE_ERROR_TYPE_RA,   MCE_RA_ERROR_LOAD_STORE_FOREIGN, MCE_ECLASS_HARDWARE,
440   MCE_INITIATOR_CPU,   MCE_SEV_SEVERE, true },
441 { 0, false, 0, 0, 0, 0, 0 } };
442 
mce_find_instr_ea_and_phys(struct pt_regs * regs,uint64_t * addr,uint64_t * phys_addr)443 static int mce_find_instr_ea_and_phys(struct pt_regs *regs, uint64_t *addr,
444 					uint64_t *phys_addr)
445 {
446 	/*
447 	 * Carefully look at the NIP to determine
448 	 * the instruction to analyse. Reading the NIP
449 	 * in real-mode is tricky and can lead to recursive
450 	 * faults
451 	 */
452 	struct ppc_inst instr;
453 	unsigned long pfn, instr_addr;
454 	struct instruction_op op;
455 	struct pt_regs tmp = *regs;
456 
457 	pfn = addr_to_pfn(regs, regs->nip);
458 	if (pfn != ULONG_MAX) {
459 		instr_addr = (pfn << PAGE_SHIFT) + (regs->nip & ~PAGE_MASK);
460 		instr = ppc_inst_read((struct ppc_inst *)instr_addr);
461 		if (!analyse_instr(&op, &tmp, instr)) {
462 			pfn = addr_to_pfn(regs, op.ea);
463 			*addr = op.ea;
464 			*phys_addr = (pfn << PAGE_SHIFT);
465 			return 0;
466 		}
467 		/*
468 		 * analyse_instr() might fail if the instruction
469 		 * is not a load/store, although this is unexpected
470 		 * for load/store errors or if we got the NIP
471 		 * wrong
472 		 */
473 	}
474 	*addr = 0;
475 	return -1;
476 }
477 
mce_handle_ierror(struct pt_regs * regs,unsigned long srr1,const struct mce_ierror_table table[],struct mce_error_info * mce_err,uint64_t * addr,uint64_t * phys_addr)478 static int mce_handle_ierror(struct pt_regs *regs, unsigned long srr1,
479 		const struct mce_ierror_table table[],
480 		struct mce_error_info *mce_err, uint64_t *addr,
481 		uint64_t *phys_addr)
482 {
483 	int handled = 0;
484 	int i;
485 
486 	*addr = 0;
487 
488 	for (i = 0; table[i].srr1_mask; i++) {
489 		if ((srr1 & table[i].srr1_mask) != table[i].srr1_value)
490 			continue;
491 
492 		/* attempt to correct the error */
493 		switch (table[i].error_type) {
494 		case MCE_ERROR_TYPE_SLB:
495 			if (local_paca->in_mce == 1)
496 				slb_save_contents(local_paca->mce_faulty_slbs);
497 			handled = mce_flush(MCE_FLUSH_SLB);
498 			break;
499 		case MCE_ERROR_TYPE_ERAT:
500 			handled = mce_flush(MCE_FLUSH_ERAT);
501 			break;
502 		case MCE_ERROR_TYPE_TLB:
503 			handled = mce_flush(MCE_FLUSH_TLB);
504 			break;
505 		}
506 
507 		/* now fill in mce_error_info */
508 		mce_err->error_type = table[i].error_type;
509 		mce_err->error_class = table[i].error_class;
510 		switch (table[i].error_type) {
511 		case MCE_ERROR_TYPE_UE:
512 			mce_err->u.ue_error_type = table[i].error_subtype;
513 			break;
514 		case MCE_ERROR_TYPE_SLB:
515 			mce_err->u.slb_error_type = table[i].error_subtype;
516 			break;
517 		case MCE_ERROR_TYPE_ERAT:
518 			mce_err->u.erat_error_type = table[i].error_subtype;
519 			break;
520 		case MCE_ERROR_TYPE_TLB:
521 			mce_err->u.tlb_error_type = table[i].error_subtype;
522 			break;
523 		case MCE_ERROR_TYPE_USER:
524 			mce_err->u.user_error_type = table[i].error_subtype;
525 			break;
526 		case MCE_ERROR_TYPE_RA:
527 			mce_err->u.ra_error_type = table[i].error_subtype;
528 			break;
529 		case MCE_ERROR_TYPE_LINK:
530 			mce_err->u.link_error_type = table[i].error_subtype;
531 			break;
532 		}
533 		mce_err->sync_error = table[i].sync_error;
534 		mce_err->severity = table[i].severity;
535 		mce_err->initiator = table[i].initiator;
536 		if (table[i].nip_valid) {
537 			*addr = regs->nip;
538 			if (mce_err->sync_error &&
539 				table[i].error_type == MCE_ERROR_TYPE_UE) {
540 				unsigned long pfn;
541 
542 				if (get_paca()->in_mce < MAX_MCE_DEPTH) {
543 					pfn = addr_to_pfn(regs, regs->nip);
544 					if (pfn != ULONG_MAX) {
545 						*phys_addr =
546 							(pfn << PAGE_SHIFT);
547 					}
548 				}
549 			}
550 		}
551 		return handled;
552 	}
553 
554 	mce_err->error_type = MCE_ERROR_TYPE_UNKNOWN;
555 	mce_err->error_class = MCE_ECLASS_UNKNOWN;
556 	mce_err->severity = MCE_SEV_SEVERE;
557 	mce_err->initiator = MCE_INITIATOR_CPU;
558 	mce_err->sync_error = true;
559 
560 	return 0;
561 }
562 
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)563 static int mce_handle_derror(struct pt_regs *regs,
564 		const struct mce_derror_table table[],
565 		struct mce_error_info *mce_err, uint64_t *addr,
566 		uint64_t *phys_addr)
567 {
568 	uint64_t dsisr = regs->dsisr;
569 	int handled = 0;
570 	int found = 0;
571 	int i;
572 
573 	*addr = 0;
574 
575 	for (i = 0; table[i].dsisr_value; i++) {
576 		if (!(dsisr & table[i].dsisr_value))
577 			continue;
578 
579 		/* attempt to correct the error */
580 		switch (table[i].error_type) {
581 		case MCE_ERROR_TYPE_SLB:
582 			if (local_paca->in_mce == 1)
583 				slb_save_contents(local_paca->mce_faulty_slbs);
584 			if (mce_flush(MCE_FLUSH_SLB))
585 				handled = 1;
586 			break;
587 		case MCE_ERROR_TYPE_ERAT:
588 			if (mce_flush(MCE_FLUSH_ERAT))
589 				handled = 1;
590 			break;
591 		case MCE_ERROR_TYPE_TLB:
592 			if (mce_flush(MCE_FLUSH_TLB))
593 				handled = 1;
594 			break;
595 		}
596 
597 		/*
598 		 * Attempt to handle multiple conditions, but only return
599 		 * one. Ensure uncorrectable errors are first in the table
600 		 * to match.
601 		 */
602 		if (found)
603 			continue;
604 
605 		/* now fill in mce_error_info */
606 		mce_err->error_type = table[i].error_type;
607 		mce_err->error_class = table[i].error_class;
608 		switch (table[i].error_type) {
609 		case MCE_ERROR_TYPE_UE:
610 			mce_err->u.ue_error_type = table[i].error_subtype;
611 			break;
612 		case MCE_ERROR_TYPE_SLB:
613 			mce_err->u.slb_error_type = table[i].error_subtype;
614 			break;
615 		case MCE_ERROR_TYPE_ERAT:
616 			mce_err->u.erat_error_type = table[i].error_subtype;
617 			break;
618 		case MCE_ERROR_TYPE_TLB:
619 			mce_err->u.tlb_error_type = table[i].error_subtype;
620 			break;
621 		case MCE_ERROR_TYPE_USER:
622 			mce_err->u.user_error_type = table[i].error_subtype;
623 			break;
624 		case MCE_ERROR_TYPE_RA:
625 			mce_err->u.ra_error_type = table[i].error_subtype;
626 			break;
627 		case MCE_ERROR_TYPE_LINK:
628 			mce_err->u.link_error_type = table[i].error_subtype;
629 			break;
630 		}
631 		mce_err->sync_error = table[i].sync_error;
632 		mce_err->severity = table[i].severity;
633 		mce_err->initiator = table[i].initiator;
634 		if (table[i].dar_valid)
635 			*addr = regs->dar;
636 		else if (mce_err->sync_error &&
637 				table[i].error_type == MCE_ERROR_TYPE_UE) {
638 			/*
639 			 * We do a maximum of 4 nested MCE calls, see
640 			 * kernel/exception-64s.h
641 			 */
642 			if (get_paca()->in_mce < MAX_MCE_DEPTH)
643 				mce_find_instr_ea_and_phys(regs, addr,
644 							   phys_addr);
645 		}
646 		found = 1;
647 	}
648 
649 	if (found)
650 		return handled;
651 
652 	mce_err->error_type = MCE_ERROR_TYPE_UNKNOWN;
653 	mce_err->error_class = MCE_ECLASS_UNKNOWN;
654 	mce_err->severity = MCE_SEV_SEVERE;
655 	mce_err->initiator = MCE_INITIATOR_CPU;
656 	mce_err->sync_error = true;
657 
658 	return 0;
659 }
660 
mce_handle_ue_error(struct pt_regs * regs,struct mce_error_info * mce_err)661 static long mce_handle_ue_error(struct pt_regs *regs,
662 				struct mce_error_info *mce_err)
663 {
664 	long handled = 0;
665 
666 	mce_common_process_ue(regs, mce_err);
667 	if (mce_err->ignore_event)
668 		return 1;
669 
670 	/*
671 	 * On specific SCOM read via MMIO we may get a machine check
672 	 * exception with SRR0 pointing inside opal. If that is the
673 	 * case OPAL may have recovery address to re-read SCOM data in
674 	 * different way and hence we can recover from this MC.
675 	 */
676 
677 	if (ppc_md.mce_check_early_recovery) {
678 		if (ppc_md.mce_check_early_recovery(regs))
679 			handled = 1;
680 	}
681 	return handled;
682 }
683 
mce_handle_error(struct pt_regs * regs,unsigned long srr1,const struct mce_derror_table dtable[],const struct mce_ierror_table itable[])684 static long mce_handle_error(struct pt_regs *regs,
685 		unsigned long srr1,
686 		const struct mce_derror_table dtable[],
687 		const struct mce_ierror_table itable[])
688 {
689 	struct mce_error_info mce_err = { 0 };
690 	uint64_t addr, phys_addr = ULONG_MAX;
691 	long handled;
692 
693 	if (SRR1_MC_LOADSTORE(srr1))
694 		handled = mce_handle_derror(regs, dtable, &mce_err, &addr,
695 				&phys_addr);
696 	else
697 		handled = mce_handle_ierror(regs, srr1, itable, &mce_err, &addr,
698 				&phys_addr);
699 
700 	if (!handled && mce_err.error_type == MCE_ERROR_TYPE_UE)
701 		handled = mce_handle_ue_error(regs, &mce_err);
702 
703 	save_mce_event(regs, handled, &mce_err, regs->nip, addr, phys_addr);
704 
705 	return handled;
706 }
707 
__machine_check_early_realmode_p7(struct pt_regs * regs)708 long __machine_check_early_realmode_p7(struct pt_regs *regs)
709 {
710 	/* P7 DD1 leaves top bits of DSISR undefined */
711 	regs->dsisr &= 0x0000ffff;
712 
713 	return mce_handle_error(regs, regs->msr,
714 			mce_p7_derror_table, mce_p7_ierror_table);
715 }
716 
__machine_check_early_realmode_p8(struct pt_regs * regs)717 long __machine_check_early_realmode_p8(struct pt_regs *regs)
718 {
719 	return mce_handle_error(regs, regs->msr,
720 			mce_p8_derror_table, mce_p8_ierror_table);
721 }
722 
__machine_check_early_realmode_p9(struct pt_regs * regs)723 long __machine_check_early_realmode_p9(struct pt_regs *regs)
724 {
725 	unsigned long srr1 = regs->msr;
726 
727 	/*
728 	 * On POWER9 DD2.1 and below, it's possible to get a machine check
729 	 * caused by a paste instruction where only DSISR bit 25 is set. This
730 	 * will result in the MCE handler seeing an unknown event and the kernel
731 	 * crashing. An MCE that occurs like this is spurious, so we don't need
732 	 * to do anything in terms of servicing it. If there is something that
733 	 * needs to be serviced, the CPU will raise the MCE again with the
734 	 * correct DSISR so that it can be serviced properly. So detect this
735 	 * case and mark it as handled.
736 	 */
737 	if (SRR1_MC_LOADSTORE(regs->msr) && regs->dsisr == 0x02000000)
738 		return 1;
739 
740 	/*
741 	 * Async machine check due to bad real address from store or foreign
742 	 * link time out comes with the load/store bit (PPC bit 42) set in
743 	 * SRR1, but the cause comes in SRR1 not DSISR. Clear bit 42 so we're
744 	 * directed to the ierror table so it will find the cause (which
745 	 * describes it correctly as a store error).
746 	 */
747 	if (SRR1_MC_LOADSTORE(srr1) &&
748 			((srr1 & 0x081c0000) == 0x08140000 ||
749 			 (srr1 & 0x081c0000) == 0x08180000)) {
750 		srr1 &= ~PPC_BIT(42);
751 	}
752 
753 	return mce_handle_error(regs, srr1,
754 			mce_p9_derror_table, mce_p9_ierror_table);
755 }
756 
__machine_check_early_realmode_p10(struct pt_regs * regs)757 long __machine_check_early_realmode_p10(struct pt_regs *regs)
758 {
759 	unsigned long srr1 = regs->msr;
760 
761 	/*
762 	 * Async machine check due to bad real address from store comes with
763 	 * the load/store bit (PPC bit 42) set in SRR1, but the cause comes in
764 	 * SRR1 not DSISR. Clear bit 42 so we're directed to the ierror table
765 	 * so it will find the cause (which describes it correctly as a store
766 	 * error).
767 	 */
768 	if (SRR1_MC_LOADSTORE(srr1) &&
769 			(srr1 & 0x081c0000) == 0x08140000) {
770 		srr1 &= ~PPC_BIT(42);
771 	}
772 
773 	return mce_handle_error(regs, srr1,
774 			mce_p10_derror_table, mce_p10_ierror_table);
775 }
776