KVM: s390: prepare to read random guest instructions
[linux-block.git] / arch / s390 / kvm / intercept.c
CommitLineData
8f2abe6a 1/*
a53c8fab 2 * in-kernel handling for sie intercepts
8f2abe6a 3 *
9a558ee3 4 * Copyright IBM Corp. 2008, 2014
8f2abe6a
CB
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License (version 2 only)
8 * as published by the Free Software Foundation.
9 *
10 * Author(s): Carsten Otte <cotte@de.ibm.com>
11 * Christian Borntraeger <borntraeger@de.ibm.com>
12 */
13
14#include <linux/kvm_host.h>
15#include <linux/errno.h>
16#include <linux/pagemap.h>
17
18#include <asm/kvm_host.h>
a86dcc24 19#include <asm/asm-offsets.h>
f14d82e0 20#include <asm/irq.h>
8f2abe6a
CB
21
22#include "kvm-s390.h"
ba5c1e9b 23#include "gaccess.h"
5786fffa 24#include "trace.h"
ade38c31 25#include "trace-s390.h"
ba5c1e9b 26
f379aae5 27
77975357 28static const intercept_handler_t instruction_handlers[256] = {
8c3f61e2 29 [0x01] = kvm_s390_handle_01,
48a3e950 30 [0x82] = kvm_s390_handle_lpsw,
e28acfea 31 [0x83] = kvm_s390_handle_diag,
80cd8763 32 [0xaa] = kvm_s390_handle_aa,
5288fbf0 33 [0xae] = kvm_s390_handle_sigp,
70455a36 34 [0xb2] = kvm_s390_handle_b2,
aba07508 35 [0xb6] = kvm_s390_handle_stctl,
953ed88d 36 [0xb7] = kvm_s390_handle_lctl,
48a3e950 37 [0xb9] = kvm_s390_handle_b9,
bb25b9ba 38 [0xe5] = kvm_s390_handle_e5,
953ed88d 39 [0xeb] = kvm_s390_handle_eb,
ba5c1e9b 40};
8f2abe6a 41
0e8bc06a 42u8 kvm_s390_get_ilen(struct kvm_vcpu *vcpu)
04b41acd
TH
43{
44 struct kvm_s390_sie_block *sie_block = vcpu->arch.sie_block;
0e8bc06a 45 u8 ilen = 0;
04b41acd 46
0e8bc06a
DH
47 switch (vcpu->arch.sie_block->icptcode) {
48 case ICPT_INST:
49 case ICPT_INSTPROGI:
50 case ICPT_OPEREXC:
51 case ICPT_PARTEXEC:
52 case ICPT_IOINST:
53 /* instruction only stored for these icptcodes */
54 ilen = insn_length(vcpu->arch.sie_block->ipa >> 8);
55 /* Use the length of the EXECUTE instruction if necessary */
56 if (sie_block->icptstatus & 1) {
57 ilen = (sie_block->icptstatus >> 4) & 0x6;
58 if (!ilen)
59 ilen = 4;
60 }
61 break;
62 case ICPT_PROGI:
63 /* bit 1+2 of pgmilc are the ilc, so we directly get ilen */
64 ilen = vcpu->arch.sie_block->pgmilc & 0x6;
65 break;
04b41acd 66 }
0e8bc06a 67 return ilen;
04b41acd
TH
68}
69
8f2abe6a
CB
70static int handle_noop(struct kvm_vcpu *vcpu)
71{
72 switch (vcpu->arch.sie_block->icptcode) {
73 case 0x10:
74 vcpu->stat.exit_external_request++;
75 break;
8f2abe6a
CB
76 default:
77 break; /* nothing */
78 }
79 return 0;
80}
81
82static int handle_stop(struct kvm_vcpu *vcpu)
83{
6cddd432 84 struct kvm_s390_local_interrupt *li = &vcpu->arch.local_int;
9ace903d 85 int rc = 0;
6cddd432 86 uint8_t flags, stop_pending;
5288fbf0 87
8f2abe6a 88 vcpu->stat.exit_stop_request++;
ade38c31 89
9a022067
DH
90 /* delay the stop if any non-stop irq is pending */
91 if (kvm_s390_vcpu_has_irq(vcpu, 1))
92 return 0;
93
6cddd432
DH
94 /* avoid races with the injection/SIGP STOP code */
95 spin_lock(&li->lock);
96 flags = li->irq.stop.flags;
97 stop_pending = kvm_s390_is_stop_irq_pending(vcpu);
98 spin_unlock(&li->lock);
32f5ff63 99
6cddd432
DH
100 trace_kvm_s390_stop_request(stop_pending, flags);
101 if (!stop_pending)
32f5ff63 102 return 0;
9ace903d 103
6cddd432 104 if (flags & KVM_S390_STOP_FLAG_STORE_STATUS) {
9e0d5473
JF
105 rc = kvm_s390_vcpu_store_status(vcpu,
106 KVM_S390_STORE_STATUS_NOADDR);
32f5ff63
DH
107 if (rc)
108 return rc;
109 }
110
6352e4d2
DH
111 if (!kvm_s390_user_cpu_state_ctrl(vcpu->kvm))
112 kvm_s390_vcpu_stop(vcpu);
32f5ff63 113 return -EOPNOTSUPP;
8f2abe6a
CB
114}
115
116static int handle_validity(struct kvm_vcpu *vcpu)
117{
118 int viwhy = vcpu->arch.sie_block->ipb >> 16;
3edbcff9 119
8f2abe6a 120 vcpu->stat.exit_validity++;
5786fffa 121 trace_kvm_s390_intercept_validity(vcpu, viwhy);
a5efb6b6
CB
122 KVM_EVENT(3, "validity intercept 0x%x for pid %u (kvm 0x%pK)", viwhy,
123 current->pid, vcpu->kvm);
124
125 /* do not warn on invalid runtime instrumentation mode */
126 WARN_ONCE(viwhy != 0x44, "kvm: unhandled validity intercept 0x%x\n",
127 viwhy);
128 return -EINVAL;
8f2abe6a
CB
129}
130
ba5c1e9b
CO
131static int handle_instruction(struct kvm_vcpu *vcpu)
132{
133 intercept_handler_t handler;
134
135 vcpu->stat.exit_instruction++;
5786fffa
CH
136 trace_kvm_s390_intercept_instruction(vcpu,
137 vcpu->arch.sie_block->ipa,
138 vcpu->arch.sie_block->ipb);
ba5c1e9b
CO
139 handler = instruction_handlers[vcpu->arch.sie_block->ipa >> 8];
140 if (handler)
141 return handler(vcpu);
b8e660b8 142 return -EOPNOTSUPP;
ba5c1e9b
CO
143}
144
f6af84e7 145static int inject_prog_on_prog_intercept(struct kvm_vcpu *vcpu)
439716a5 146{
f6af84e7
DH
147 struct kvm_s390_pgm_info pgm_info = {
148 .code = vcpu->arch.sie_block->iprcc,
eaa4f416
DH
149 /* the PSW has already been rewound */
150 .flags = KVM_S390_PGM_FLAGS_NO_REWIND,
f6af84e7 151 };
439716a5
DH
152
153 switch (vcpu->arch.sie_block->iprcc & ~PGM_PER) {
154 case PGM_AFX_TRANSLATION:
155 case PGM_ASX_TRANSLATION:
156 case PGM_EX_TRANSLATION:
157 case PGM_LFX_TRANSLATION:
158 case PGM_LSTE_SEQUENCE:
159 case PGM_LSX_TRANSLATION:
160 case PGM_LX_TRANSLATION:
161 case PGM_PRIMARY_AUTHORITY:
162 case PGM_SECONDARY_AUTHORITY:
163 case PGM_SPACE_SWITCH:
f6af84e7 164 pgm_info.trans_exc_code = vcpu->arch.sie_block->tecmc;
439716a5
DH
165 break;
166 case PGM_ALEN_TRANSLATION:
167 case PGM_ALE_SEQUENCE:
168 case PGM_ASTE_INSTANCE:
169 case PGM_ASTE_SEQUENCE:
170 case PGM_ASTE_VALIDITY:
171 case PGM_EXTENDED_AUTHORITY:
f6af84e7 172 pgm_info.exc_access_id = vcpu->arch.sie_block->eai;
439716a5
DH
173 break;
174 case PGM_ASCE_TYPE:
175 case PGM_PAGE_TRANSLATION:
176 case PGM_REGION_FIRST_TRANS:
177 case PGM_REGION_SECOND_TRANS:
178 case PGM_REGION_THIRD_TRANS:
179 case PGM_SEGMENT_TRANSLATION:
f6af84e7
DH
180 pgm_info.trans_exc_code = vcpu->arch.sie_block->tecmc;
181 pgm_info.exc_access_id = vcpu->arch.sie_block->eai;
182 pgm_info.op_access_id = vcpu->arch.sie_block->oai;
439716a5
DH
183 break;
184 case PGM_MONITOR:
f6af84e7
DH
185 pgm_info.mon_class_nr = vcpu->arch.sie_block->mcn;
186 pgm_info.mon_code = vcpu->arch.sie_block->tecmc;
439716a5 187 break;
403c8648 188 case PGM_VECTOR_PROCESSING:
439716a5 189 case PGM_DATA:
f6af84e7 190 pgm_info.data_exc_code = vcpu->arch.sie_block->dxc;
439716a5
DH
191 break;
192 case PGM_PROTECTION:
f6af84e7
DH
193 pgm_info.trans_exc_code = vcpu->arch.sie_block->tecmc;
194 pgm_info.exc_access_id = vcpu->arch.sie_block->eai;
439716a5
DH
195 break;
196 default:
197 break;
198 }
199
200 if (vcpu->arch.sie_block->iprcc & PGM_PER) {
f6af84e7
DH
201 pgm_info.per_code = vcpu->arch.sie_block->perc;
202 pgm_info.per_atmid = vcpu->arch.sie_block->peratmid;
203 pgm_info.per_address = vcpu->arch.sie_block->peraddr;
204 pgm_info.per_access_id = vcpu->arch.sie_block->peraid;
439716a5 205 }
f6af84e7 206 return kvm_s390_inject_prog_irq(vcpu, &pgm_info);
439716a5
DH
207}
208
e325fe69
MM
209/*
210 * restore ITDB to program-interruption TDB in guest lowcore
211 * and set TX abort indication if required
212*/
213static int handle_itdb(struct kvm_vcpu *vcpu)
214{
215 struct kvm_s390_itdb *itdb;
216 int rc;
217
218 if (!IS_TE_ENABLED(vcpu) || !IS_ITDB_VALID(vcpu))
219 return 0;
220 if (current->thread.per_flags & PER_FLAG_NO_TE)
221 return 0;
222 itdb = (struct kvm_s390_itdb *)vcpu->arch.sie_block->itdba;
223 rc = write_guest_lc(vcpu, __LC_PGM_TDB, itdb, sizeof(*itdb));
224 if (rc)
225 return rc;
226 memset(itdb, 0, sizeof(*itdb));
227
228 return 0;
229}
230
27291e21
DH
231#define per_event(vcpu) (vcpu->arch.sie_block->iprcc & PGM_PER)
232
ba5c1e9b
CO
233static int handle_prog(struct kvm_vcpu *vcpu)
234{
684135e0 235 psw_t psw;
0040e7d2
HC
236 int rc;
237
ba5c1e9b 238 vcpu->stat.exit_program_interruption++;
7feb6bb8 239
27291e21
DH
240 if (guestdbg_enabled(vcpu) && per_event(vcpu)) {
241 kvm_s390_handle_per_event(vcpu);
242 /* the interrupt might have been filtered out completely */
243 if (vcpu->arch.sie_block->iprcc == 0)
244 return 0;
245 }
246
e325fe69 247 trace_kvm_s390_intercept_prog(vcpu, vcpu->arch.sie_block->iprcc);
684135e0
TH
248 if (vcpu->arch.sie_block->iprcc == PGM_SPECIFICATION) {
249 rc = read_guest_lc(vcpu, __LC_PGM_NEW_PSW, &psw, sizeof(psw_t));
250 if (rc)
251 return rc;
252 /* Avoid endless loops of specification exceptions */
253 if (!is_valid_psw(&psw))
254 return -EOPNOTSUPP;
255 }
e325fe69 256 rc = handle_itdb(vcpu);
0040e7d2
HC
257 if (rc)
258 return rc;
439716a5 259
f6af84e7 260 return inject_prog_on_prog_intercept(vcpu);
ba5c1e9b
CO
261}
262
f14d82e0
TH
263/**
264 * handle_external_interrupt - used for external interruption interceptions
265 *
266 * This interception only occurs if the CPUSTAT_EXT_INT bit was set, or if
267 * the new PSW does not have external interrupts disabled. In the first case,
268 * we've got to deliver the interrupt manually, and in the second case, we
269 * drop to userspace to handle the situation there.
270 */
271static int handle_external_interrupt(struct kvm_vcpu *vcpu)
272{
273 u16 eic = vcpu->arch.sie_block->eic;
383d0b05 274 struct kvm_s390_irq irq;
f14d82e0
TH
275 psw_t newpsw;
276 int rc;
277
278 vcpu->stat.exit_external_interrupt++;
279
280 rc = read_guest_lc(vcpu, __LC_EXT_NEW_PSW, &newpsw, sizeof(psw_t));
281 if (rc)
282 return rc;
283 /* We can not handle clock comparator or timer interrupt with bad PSW */
284 if ((eic == EXT_IRQ_CLK_COMP || eic == EXT_IRQ_CPU_TIMER) &&
285 (newpsw.mask & PSW_MASK_EXT))
286 return -EOPNOTSUPP;
287
288 switch (eic) {
289 case EXT_IRQ_CLK_COMP:
290 irq.type = KVM_S390_INT_CLOCK_COMP;
291 break;
292 case EXT_IRQ_CPU_TIMER:
293 irq.type = KVM_S390_INT_CPU_TIMER;
294 break;
295 case EXT_IRQ_EXTERNAL_CALL:
296 irq.type = KVM_S390_INT_EXTERNAL_CALL;
383d0b05 297 irq.u.extcall.code = vcpu->arch.sie_block->extcpuaddr;
ea5f4969
DH
298 rc = kvm_s390_inject_vcpu(vcpu, &irq);
299 /* ignore if another external call is already pending */
300 if (rc == -EBUSY)
301 return 0;
302 return rc;
f14d82e0
TH
303 default:
304 return -EOPNOTSUPP;
305 }
306
307 return kvm_s390_inject_vcpu(vcpu, &irq);
308}
309
9a558ee3
TH
310/**
311 * Handle MOVE PAGE partial execution interception.
312 *
313 * This interception can only happen for guests with DAT disabled and
314 * addresses that are currently not mapped in the host. Thus we try to
315 * set up the mappings for the corresponding user pages here (or throw
316 * addressing exceptions in case of illegal guest addresses).
317 */
318static int handle_mvpg_pei(struct kvm_vcpu *vcpu)
319{
f22166dc 320 unsigned long srcaddr, dstaddr;
9a558ee3
TH
321 int reg1, reg2, rc;
322
323 kvm_s390_get_regs_rre(vcpu, &reg1, &reg2);
9a558ee3
TH
324
325 /* Make sure that the source is paged-in */
3cfad023 326 rc = guest_translate_address(vcpu, vcpu->run->s.regs.gprs[reg2],
92c96321 327 reg2, &srcaddr, GACC_FETCH);
3cfad023
TH
328 if (rc)
329 return kvm_s390_inject_prog_cond(vcpu, rc);
f22166dc
TH
330 rc = kvm_arch_fault_in_page(vcpu, srcaddr, 0);
331 if (rc != 0)
9a558ee3
TH
332 return rc;
333
334 /* Make sure that the destination is paged-in */
3cfad023 335 rc = guest_translate_address(vcpu, vcpu->run->s.regs.gprs[reg1],
92c96321 336 reg1, &dstaddr, GACC_STORE);
3cfad023
TH
337 if (rc)
338 return kvm_s390_inject_prog_cond(vcpu, rc);
f22166dc
TH
339 rc = kvm_arch_fault_in_page(vcpu, dstaddr, 1);
340 if (rc != 0)
9a558ee3
TH
341 return rc;
342
0e8bc06a 343 kvm_s390_retry_instr(vcpu);
9a558ee3
TH
344
345 return 0;
346}
347
348static int handle_partial_execution(struct kvm_vcpu *vcpu)
349{
9ec6de19
AY
350 vcpu->stat.exit_pei++;
351
9a558ee3
TH
352 if (vcpu->arch.sie_block->ipa == 0xb254) /* MVPG */
353 return handle_mvpg_pei(vcpu);
4953919f
DH
354 if (vcpu->arch.sie_block->ipa >> 8 == 0xae) /* SIGP */
355 return kvm_s390_handle_sigp_pei(vcpu);
9a558ee3
TH
356
357 return -EOPNOTSUPP;
358}
359
a011eeb2
JF
360static int handle_operexc(struct kvm_vcpu *vcpu)
361{
362 vcpu->stat.exit_operation_exception++;
363 trace_kvm_s390_handle_operexc(vcpu, vcpu->arch.sie_block->ipa,
364 vcpu->arch.sie_block->ipb);
365
95ca2cb5
JF
366 if (vcpu->arch.sie_block->ipa == 0xb256 &&
367 test_kvm_facility(vcpu->kvm, 74))
368 return handle_sthyi(vcpu);
369
6502a34c
DH
370 if (vcpu->arch.sie_block->ipa == 0 && vcpu->kvm->arch.user_instr0)
371 return -EOPNOTSUPP;
372
a011eeb2
JF
373 return kvm_s390_inject_program_int(vcpu, PGM_OPERATION);
374}
375
8f2abe6a
CB
376int kvm_handle_sie_intercept(struct kvm_vcpu *vcpu)
377{
5ffe466c
DH
378 int rc, per_rc = 0;
379
71f116bf
DH
380 if (kvm_is_ucontrol(vcpu->kvm))
381 return -EOPNOTSUPP;
382
46b708ea 383 switch (vcpu->arch.sie_block->icptcode) {
46b708ea
CB
384 case 0x10:
385 case 0x18:
386 return handle_noop(vcpu);
387 case 0x04:
5ffe466c
DH
388 rc = handle_instruction(vcpu);
389 break;
46b708ea
CB
390 case 0x08:
391 return handle_prog(vcpu);
392 case 0x14:
393 return handle_external_interrupt(vcpu);
394 case 0x1c:
395 return kvm_s390_handle_wait(vcpu);
396 case 0x20:
397 return handle_validity(vcpu);
398 case 0x28:
399 return handle_stop(vcpu);
a011eeb2 400 case 0x2c:
5ffe466c
DH
401 rc = handle_operexc(vcpu);
402 break;
46b708ea 403 case 0x38:
5ffe466c
DH
404 rc = handle_partial_execution(vcpu);
405 break;
46b708ea 406 default:
b8e660b8 407 return -EOPNOTSUPP;
46b708ea 408 }
5ffe466c
DH
409
410 /* process PER, also if the instrution is processed in user space */
411 if (vcpu->arch.sie_block->icptstatus & 0x02 &&
412 (!rc || rc == -EOPNOTSUPP))
413 per_rc = kvm_s390_handle_per_ifetch_icpt(vcpu);
414 return per_rc ? per_rc : rc;
8f2abe6a 415}