1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Copyright (C) 2015 - ARM Ltd
4 * Author: Marc Zyngier <marc.zyngier@arm.com>
5 */
6
7 #include <hyp/switch.h>
8
9 #include <linux/arm-smccc.h>
10 #include <linux/kvm_host.h>
11 #include <linux/types.h>
12 #include <linux/jump_label.h>
13 #include <linux/percpu.h>
14 #include <uapi/linux/psci.h>
15
16 #include <kvm/arm_psci.h>
17
18 #include <asm/barrier.h>
19 #include <asm/cpufeature.h>
20 #include <asm/kprobes.h>
21 #include <asm/kvm_asm.h>
22 #include <asm/kvm_emulate.h>
23 #include <asm/kvm_hyp.h>
24 #include <asm/kvm_mmu.h>
25 #include <asm/fpsimd.h>
26 #include <asm/debug-monitors.h>
27 #include <asm/processor.h>
28 #include <asm/thread_info.h>
29 #include <asm/vectors.h>
30
31 /* VHE specific context */
32 DEFINE_PER_CPU(struct kvm_host_data, kvm_host_data);
33 DEFINE_PER_CPU(struct kvm_cpu_context, kvm_hyp_ctxt);
34 DEFINE_PER_CPU(unsigned long, kvm_hyp_vector);
35
36 /*
37 * HCR_EL2 bits that the NV guest can freely change (no RES0/RES1
38 * semantics, irrespective of the configuration), but that cannot be
39 * applied to the actual HW as things would otherwise break badly.
40 *
41 * - TGE: we want the guest to use EL1, which is incompatible with
42 * this bit being set
43 *
44 * - API/APK: they are already accounted for by vcpu_load(), and can
45 * only take effect across a load/put cycle (such as ERET)
46 *
47 * - FIEN: no way we let a guest have access to the RAS "Common Fault
48 * Injection" thing, whatever that does
49 */
50 #define NV_HCR_GUEST_EXCLUDE (HCR_TGE | HCR_API | HCR_APK | HCR_FIEN)
51
__compute_hcr(struct kvm_vcpu * vcpu)52 static u64 __compute_hcr(struct kvm_vcpu *vcpu)
53 {
54 u64 guest_hcr, hcr = vcpu->arch.hcr_el2;
55
56 if (!vcpu_has_nv(vcpu))
57 return hcr;
58
59 /*
60 * We rely on the invariant that a vcpu entered from HYP
61 * context must also exit in the same context, as only an ERET
62 * instruction can kick us out of it, and we obviously trap
63 * that sucker. PSTATE.M will get fixed-up on exit.
64 */
65 if (is_hyp_ctxt(vcpu)) {
66 host_data_set_flag(VCPU_IN_HYP_CONTEXT);
67
68 hcr |= HCR_NV | HCR_NV2 | HCR_AT | HCR_TTLB;
69
70 if (!vcpu_el2_e2h_is_set(vcpu))
71 hcr |= HCR_NV1;
72
73 /*
74 * Nothing in HCR_EL2 should impact running in hypervisor
75 * context, apart from bits we have defined as RESx (E2H,
76 * HCD and co), or that cannot be set directly (the EXCLUDE
77 * bits). Given that we OR the guest's view with the host's,
78 * we can use the 0 value as the starting point, and only
79 * use the config-driven RES1 bits.
80 */
81 guest_hcr = kvm_vcpu_apply_reg_masks(vcpu, HCR_EL2, 0);
82
83 write_sysreg_s(vcpu->arch.ctxt.vncr_array, SYS_VNCR_EL2);
84 } else {
85 host_data_clear_flag(VCPU_IN_HYP_CONTEXT);
86
87 guest_hcr = __vcpu_sys_reg(vcpu, HCR_EL2);
88 if (guest_hcr & HCR_NV) {
89 u64 va = __fix_to_virt(vncr_fixmap(smp_processor_id()));
90
91 /* Inherit the low bits from the actual register */
92 va |= __vcpu_sys_reg(vcpu, VNCR_EL2) & GENMASK(PAGE_SHIFT - 1, 0);
93 write_sysreg_s(va, SYS_VNCR_EL2);
94
95 /* Force NV2 in case the guest is forgetful... */
96 guest_hcr |= HCR_NV2;
97 }
98
99 /*
100 * Exclude the guest's TWED configuration if it hasn't set TWE
101 * to avoid potentially delaying traps for the host.
102 */
103 if (!(guest_hcr & HCR_TWE))
104 guest_hcr &= ~(HCR_EL2_TWEDEn | HCR_EL2_TWEDEL);
105 }
106
107 BUG_ON(host_data_test_flag(VCPU_IN_HYP_CONTEXT) &&
108 host_data_test_flag(L1_VNCR_MAPPED));
109
110 return hcr | (guest_hcr & ~NV_HCR_GUEST_EXCLUDE);
111 }
112
__activate_traps(struct kvm_vcpu * vcpu)113 static void __activate_traps(struct kvm_vcpu *vcpu)
114 {
115 u64 val;
116
117 ___activate_traps(vcpu, __compute_hcr(vcpu));
118
119 if (has_cntpoff()) {
120 struct timer_map map;
121
122 get_timer_map(vcpu, &map);
123
124 /*
125 * We're entrering the guest. Reload the correct
126 * values from memory now that TGE is clear.
127 */
128 if (map.direct_ptimer == vcpu_ptimer(vcpu))
129 val = __vcpu_sys_reg(vcpu, CNTP_CVAL_EL0);
130 if (map.direct_ptimer == vcpu_hptimer(vcpu))
131 val = __vcpu_sys_reg(vcpu, CNTHP_CVAL_EL2);
132
133 if (map.direct_ptimer) {
134 write_sysreg_el0(val, SYS_CNTP_CVAL);
135 isb();
136 }
137 }
138
139 __activate_cptr_traps(vcpu);
140
141 write_sysreg(__this_cpu_read(kvm_hyp_vector), vbar_el1);
142 }
143 NOKPROBE_SYMBOL(__activate_traps);
144
__deactivate_traps(struct kvm_vcpu * vcpu)145 static void __deactivate_traps(struct kvm_vcpu *vcpu)
146 {
147 const char *host_vectors = vectors;
148
149 ___deactivate_traps(vcpu);
150
151 write_sysreg_hcr(HCR_HOST_VHE_FLAGS);
152
153 if (has_cntpoff()) {
154 struct timer_map map;
155 u64 val, offset;
156
157 get_timer_map(vcpu, &map);
158
159 /*
160 * We're exiting the guest. Save the latest CVAL value
161 * to memory and apply the offset now that TGE is set.
162 */
163 val = read_sysreg_el0(SYS_CNTP_CVAL);
164 if (map.direct_ptimer == vcpu_ptimer(vcpu))
165 __vcpu_assign_sys_reg(vcpu, CNTP_CVAL_EL0, val);
166 if (map.direct_ptimer == vcpu_hptimer(vcpu))
167 __vcpu_assign_sys_reg(vcpu, CNTHP_CVAL_EL2, val);
168
169 offset = read_sysreg_s(SYS_CNTPOFF_EL2);
170
171 if (map.direct_ptimer && offset) {
172 write_sysreg_el0(val + offset, SYS_CNTP_CVAL);
173 isb();
174 }
175 }
176
177 /*
178 * ARM errata 1165522 and 1530923 require the actual execution of the
179 * above before we can switch to the EL2/EL0 translation regime used by
180 * the host.
181 */
182 asm(ALTERNATIVE("nop", "isb", ARM64_WORKAROUND_SPECULATIVE_AT));
183
184 __deactivate_cptr_traps(vcpu);
185
186 if (!arm64_kernel_unmapped_at_el0())
187 host_vectors = __this_cpu_read(this_cpu_vector);
188 write_sysreg(host_vectors, vbar_el1);
189 }
190 NOKPROBE_SYMBOL(__deactivate_traps);
191
192 /*
193 * Disable IRQs in __vcpu_{load,put}_{activate,deactivate}_traps() to
194 * prevent a race condition between context switching of PMUSERENR_EL0
195 * in __{activate,deactivate}_traps_common() and IPIs that attempts to
196 * update PMUSERENR_EL0. See also kvm_set_pmuserenr().
197 */
__vcpu_load_activate_traps(struct kvm_vcpu * vcpu)198 static void __vcpu_load_activate_traps(struct kvm_vcpu *vcpu)
199 {
200 unsigned long flags;
201
202 local_irq_save(flags);
203 __activate_traps_common(vcpu);
204 local_irq_restore(flags);
205 }
206
__vcpu_put_deactivate_traps(struct kvm_vcpu * vcpu)207 static void __vcpu_put_deactivate_traps(struct kvm_vcpu *vcpu)
208 {
209 unsigned long flags;
210
211 local_irq_save(flags);
212 __deactivate_traps_common(vcpu);
213 local_irq_restore(flags);
214 }
215
kvm_vcpu_load_vhe(struct kvm_vcpu * vcpu)216 void kvm_vcpu_load_vhe(struct kvm_vcpu *vcpu)
217 {
218 host_data_ptr(host_ctxt)->__hyp_running_vcpu = vcpu;
219
220 __vcpu_load_switch_sysregs(vcpu);
221 __vcpu_load_activate_traps(vcpu);
222 __load_stage2(vcpu->arch.hw_mmu, vcpu->arch.hw_mmu->arch);
223 }
224
kvm_vcpu_put_vhe(struct kvm_vcpu * vcpu)225 void kvm_vcpu_put_vhe(struct kvm_vcpu *vcpu)
226 {
227 __vcpu_put_deactivate_traps(vcpu);
228 __vcpu_put_switch_sysregs(vcpu);
229
230 host_data_ptr(host_ctxt)->__hyp_running_vcpu = NULL;
231 }
232
compute_emulated_cntx_ctl_el0(struct kvm_vcpu * vcpu,enum vcpu_sysreg reg)233 static u64 compute_emulated_cntx_ctl_el0(struct kvm_vcpu *vcpu,
234 enum vcpu_sysreg reg)
235 {
236 unsigned long ctl;
237 u64 cval, cnt;
238 bool stat;
239
240 switch (reg) {
241 case CNTP_CTL_EL0:
242 cval = __vcpu_sys_reg(vcpu, CNTP_CVAL_EL0);
243 ctl = __vcpu_sys_reg(vcpu, CNTP_CTL_EL0);
244 cnt = compute_counter_value(vcpu_ptimer(vcpu));
245 break;
246 case CNTV_CTL_EL0:
247 cval = __vcpu_sys_reg(vcpu, CNTV_CVAL_EL0);
248 ctl = __vcpu_sys_reg(vcpu, CNTV_CTL_EL0);
249 cnt = compute_counter_value(vcpu_vtimer(vcpu));
250 break;
251 default:
252 BUG();
253 }
254
255 stat = cval <= cnt;
256 __assign_bit(__ffs(ARCH_TIMER_CTRL_IT_STAT), &ctl, stat);
257
258 return ctl;
259 }
260
kvm_hyp_handle_timer(struct kvm_vcpu * vcpu,u64 * exit_code)261 static bool kvm_hyp_handle_timer(struct kvm_vcpu *vcpu, u64 *exit_code)
262 {
263 u64 esr, val;
264
265 /*
266 * Having FEAT_ECV allows for a better quality of timer emulation.
267 * However, this comes at a huge cost in terms of traps. Try and
268 * satisfy the reads from guest's hypervisor context without
269 * returning to the kernel if we can.
270 */
271 if (!is_hyp_ctxt(vcpu))
272 return false;
273
274 esr = kvm_vcpu_get_esr(vcpu);
275 if ((esr & ESR_ELx_SYS64_ISS_DIR_MASK) != ESR_ELx_SYS64_ISS_DIR_READ)
276 return false;
277
278 switch (esr_sys64_to_sysreg(esr)) {
279 case SYS_CNTP_CTL_EL02:
280 val = compute_emulated_cntx_ctl_el0(vcpu, CNTP_CTL_EL0);
281 break;
282 case SYS_CNTP_CTL_EL0:
283 if (vcpu_el2_e2h_is_set(vcpu))
284 val = read_sysreg_el0(SYS_CNTP_CTL);
285 else
286 val = compute_emulated_cntx_ctl_el0(vcpu, CNTP_CTL_EL0);
287 break;
288 case SYS_CNTP_CVAL_EL02:
289 val = __vcpu_sys_reg(vcpu, CNTP_CVAL_EL0);
290 break;
291 case SYS_CNTP_CVAL_EL0:
292 if (vcpu_el2_e2h_is_set(vcpu)) {
293 val = read_sysreg_el0(SYS_CNTP_CVAL);
294
295 if (!has_cntpoff())
296 val -= timer_get_offset(vcpu_hptimer(vcpu));
297 } else {
298 val = __vcpu_sys_reg(vcpu, CNTP_CVAL_EL0);
299 }
300 break;
301 case SYS_CNTPCT_EL0:
302 case SYS_CNTPCTSS_EL0:
303 val = compute_counter_value(vcpu_hptimer(vcpu));
304 break;
305 case SYS_CNTV_CTL_EL02:
306 val = compute_emulated_cntx_ctl_el0(vcpu, CNTV_CTL_EL0);
307 break;
308 case SYS_CNTV_CTL_EL0:
309 if (vcpu_el2_e2h_is_set(vcpu))
310 val = read_sysreg_el0(SYS_CNTV_CTL);
311 else
312 val = compute_emulated_cntx_ctl_el0(vcpu, CNTV_CTL_EL0);
313 break;
314 case SYS_CNTV_CVAL_EL02:
315 val = __vcpu_sys_reg(vcpu, CNTV_CVAL_EL0);
316 break;
317 case SYS_CNTV_CVAL_EL0:
318 if (vcpu_el2_e2h_is_set(vcpu))
319 val = read_sysreg_el0(SYS_CNTV_CVAL);
320 else
321 val = __vcpu_sys_reg(vcpu, CNTV_CVAL_EL0);
322 break;
323 case SYS_CNTVCT_EL0:
324 case SYS_CNTVCTSS_EL0:
325 val = compute_counter_value(vcpu_hvtimer(vcpu));
326 break;
327 default:
328 return false;
329 }
330
331 vcpu_set_reg(vcpu, kvm_vcpu_sys_get_rt(vcpu), val);
332 __kvm_skip_instr(vcpu);
333
334 return true;
335 }
336
kvm_hyp_handle_eret(struct kvm_vcpu * vcpu,u64 * exit_code)337 static bool kvm_hyp_handle_eret(struct kvm_vcpu *vcpu, u64 *exit_code)
338 {
339 u64 esr = kvm_vcpu_get_esr(vcpu);
340 u64 spsr, elr, mode;
341
342 /*
343 * Going through the whole put/load motions is a waste of time
344 * if this is a VHE guest hypervisor returning to its own
345 * userspace, or the hypervisor performing a local exception
346 * return. No need to save/restore registers, no need to
347 * switch S2 MMU. Just do the canonical ERET.
348 *
349 * Unless the trap has to be forwarded further down the line,
350 * of course...
351 */
352 if ((__vcpu_sys_reg(vcpu, HCR_EL2) & HCR_NV) ||
353 (__vcpu_sys_reg(vcpu, HFGITR_EL2) & HFGITR_EL2_ERET))
354 return false;
355
356 spsr = read_sysreg_el1(SYS_SPSR);
357 mode = spsr & (PSR_MODE_MASK | PSR_MODE32_BIT);
358
359 switch (mode) {
360 case PSR_MODE_EL0t:
361 if (!(vcpu_el2_e2h_is_set(vcpu) && vcpu_el2_tge_is_set(vcpu)))
362 return false;
363 break;
364 case PSR_MODE_EL2t:
365 mode = PSR_MODE_EL1t;
366 break;
367 case PSR_MODE_EL2h:
368 mode = PSR_MODE_EL1h;
369 break;
370 default:
371 return false;
372 }
373
374 /* If ERETAx fails, take the slow path */
375 if (esr_iss_is_eretax(esr)) {
376 if (!(vcpu_has_ptrauth(vcpu) && kvm_auth_eretax(vcpu, &elr)))
377 return false;
378 } else {
379 elr = read_sysreg_el1(SYS_ELR);
380 }
381
382 spsr = (spsr & ~(PSR_MODE_MASK | PSR_MODE32_BIT)) | mode;
383
384 write_sysreg_el2(spsr, SYS_SPSR);
385 write_sysreg_el2(elr, SYS_ELR);
386
387 return true;
388 }
389
kvm_hyp_handle_tlbi_el2(struct kvm_vcpu * vcpu,u64 * exit_code)390 static bool kvm_hyp_handle_tlbi_el2(struct kvm_vcpu *vcpu, u64 *exit_code)
391 {
392 int ret = -EINVAL;
393 u32 instr;
394 u64 val;
395
396 /*
397 * Ideally, we would never trap on EL2 S1 TLB invalidations using
398 * the EL1 instructions when the guest's HCR_EL2.{E2H,TGE}=={1,1}.
399 * But "thanks" to FEAT_NV2, we don't trap writes to HCR_EL2,
400 * meaning that we can't track changes to the virtual TGE bit. So we
401 * have to leave HCR_EL2.TTLB set on the host. Oopsie...
402 *
403 * Try and handle these invalidation as quickly as possible, without
404 * fully exiting. Note that we don't need to consider any forwarding
405 * here, as having E2H+TGE set is the very definition of being
406 * InHost.
407 *
408 * For the lesser hypervisors out there that have failed to get on
409 * with the VHE program, we can also handle the nVHE style of EL2
410 * invalidation.
411 */
412 if (!(is_hyp_ctxt(vcpu)))
413 return false;
414
415 instr = esr_sys64_to_sysreg(kvm_vcpu_get_esr(vcpu));
416 val = vcpu_get_reg(vcpu, kvm_vcpu_sys_get_rt(vcpu));
417
418 if ((kvm_supported_tlbi_s1e1_op(vcpu, instr) &&
419 vcpu_el2_e2h_is_set(vcpu) && vcpu_el2_tge_is_set(vcpu)) ||
420 kvm_supported_tlbi_s1e2_op (vcpu, instr))
421 ret = __kvm_tlbi_s1e2(NULL, val, instr);
422
423 if (ret)
424 return false;
425
426 /*
427 * If we have to check for any VNCR mapping being invalidated,
428 * go back to the slow path for further processing.
429 */
430 if (vcpu_el2_e2h_is_set(vcpu) && vcpu_el2_tge_is_set(vcpu) &&
431 atomic_read(&vcpu->kvm->arch.vncr_map_count))
432 return false;
433
434 __kvm_skip_instr(vcpu);
435
436 return true;
437 }
438
kvm_hyp_handle_cpacr_el1(struct kvm_vcpu * vcpu,u64 * exit_code)439 static bool kvm_hyp_handle_cpacr_el1(struct kvm_vcpu *vcpu, u64 *exit_code)
440 {
441 u64 esr = kvm_vcpu_get_esr(vcpu);
442 int rt;
443
444 if (!is_hyp_ctxt(vcpu) || esr_sys64_to_sysreg(esr) != SYS_CPACR_EL1)
445 return false;
446
447 rt = kvm_vcpu_sys_get_rt(vcpu);
448
449 if ((esr & ESR_ELx_SYS64_ISS_DIR_MASK) == ESR_ELx_SYS64_ISS_DIR_READ) {
450 vcpu_set_reg(vcpu, rt, __vcpu_sys_reg(vcpu, CPTR_EL2));
451 } else {
452 vcpu_write_sys_reg(vcpu, vcpu_get_reg(vcpu, rt), CPTR_EL2);
453 __activate_cptr_traps(vcpu);
454 }
455
456 __kvm_skip_instr(vcpu);
457
458 return true;
459 }
460
kvm_hyp_handle_zcr_el2(struct kvm_vcpu * vcpu,u64 * exit_code)461 static bool kvm_hyp_handle_zcr_el2(struct kvm_vcpu *vcpu, u64 *exit_code)
462 {
463 u32 sysreg = esr_sys64_to_sysreg(kvm_vcpu_get_esr(vcpu));
464
465 if (!vcpu_has_nv(vcpu))
466 return false;
467
468 if (sysreg != SYS_ZCR_EL2)
469 return false;
470
471 if (guest_owns_fp_regs())
472 return false;
473
474 /*
475 * ZCR_EL2 traps are handled in the slow path, with the expectation
476 * that the guest's FP context has already been loaded onto the CPU.
477 *
478 * Load the guest's FP context and unconditionally forward to the
479 * slow path for handling (i.e. return false).
480 */
481 kvm_hyp_handle_fpsimd(vcpu, exit_code);
482 return false;
483 }
484
kvm_hyp_handle_sysreg_vhe(struct kvm_vcpu * vcpu,u64 * exit_code)485 static bool kvm_hyp_handle_sysreg_vhe(struct kvm_vcpu *vcpu, u64 *exit_code)
486 {
487 if (kvm_hyp_handle_tlbi_el2(vcpu, exit_code))
488 return true;
489
490 if (kvm_hyp_handle_timer(vcpu, exit_code))
491 return true;
492
493 if (kvm_hyp_handle_cpacr_el1(vcpu, exit_code))
494 return true;
495
496 if (kvm_hyp_handle_zcr_el2(vcpu, exit_code))
497 return true;
498
499 return kvm_hyp_handle_sysreg(vcpu, exit_code);
500 }
501
kvm_hyp_handle_impdef(struct kvm_vcpu * vcpu,u64 * exit_code)502 static bool kvm_hyp_handle_impdef(struct kvm_vcpu *vcpu, u64 *exit_code)
503 {
504 u64 iss;
505
506 if (!cpus_have_final_cap(ARM64_WORKAROUND_PMUV3_IMPDEF_TRAPS))
507 return false;
508
509 /*
510 * Compute a synthetic ESR for a sysreg trap. Conveniently, AFSR1_EL2
511 * is populated with a correct ISS for a sysreg trap. These fruity
512 * parts are 64bit only, so unconditionally set IL.
513 */
514 iss = ESR_ELx_ISS(read_sysreg_s(SYS_AFSR1_EL2));
515 vcpu->arch.fault.esr_el2 = FIELD_PREP(ESR_ELx_EC_MASK, ESR_ELx_EC_SYS64) |
516 FIELD_PREP(ESR_ELx_ISS_MASK, iss) |
517 ESR_ELx_IL;
518 return false;
519 }
520
521 static const exit_handler_fn hyp_exit_handlers[] = {
522 [0 ... ESR_ELx_EC_MAX] = NULL,
523 [ESR_ELx_EC_CP15_32] = kvm_hyp_handle_cp15_32,
524 [ESR_ELx_EC_SYS64] = kvm_hyp_handle_sysreg_vhe,
525 [ESR_ELx_EC_SVE] = kvm_hyp_handle_fpsimd,
526 [ESR_ELx_EC_FP_ASIMD] = kvm_hyp_handle_fpsimd,
527 [ESR_ELx_EC_IABT_LOW] = kvm_hyp_handle_iabt_low,
528 [ESR_ELx_EC_DABT_LOW] = kvm_hyp_handle_dabt_low,
529 [ESR_ELx_EC_WATCHPT_LOW] = kvm_hyp_handle_watchpt_low,
530 [ESR_ELx_EC_ERET] = kvm_hyp_handle_eret,
531 [ESR_ELx_EC_MOPS] = kvm_hyp_handle_mops,
532
533 /* Apple shenanigans */
534 [0x3F] = kvm_hyp_handle_impdef,
535 };
536
fixup_guest_exit(struct kvm_vcpu * vcpu,u64 * exit_code)537 static inline bool fixup_guest_exit(struct kvm_vcpu *vcpu, u64 *exit_code)
538 {
539 synchronize_vcpu_pstate(vcpu, exit_code);
540
541 /*
542 * If we were in HYP context on entry, adjust the PSTATE view
543 * so that the usual helpers work correctly. This enforces our
544 * invariant that the guest's HYP context status is preserved
545 * across a run.
546 */
547 if (vcpu_has_nv(vcpu) &&
548 unlikely(host_data_test_flag(VCPU_IN_HYP_CONTEXT))) {
549 u64 mode = *vcpu_cpsr(vcpu) & (PSR_MODE_MASK | PSR_MODE32_BIT);
550
551 switch (mode) {
552 case PSR_MODE_EL1t:
553 mode = PSR_MODE_EL2t;
554 break;
555 case PSR_MODE_EL1h:
556 mode = PSR_MODE_EL2h;
557 break;
558 }
559
560 *vcpu_cpsr(vcpu) &= ~(PSR_MODE_MASK | PSR_MODE32_BIT);
561 *vcpu_cpsr(vcpu) |= mode;
562 }
563
564 /* Apply extreme paranoia! */
565 BUG_ON(vcpu_has_nv(vcpu) &&
566 !!host_data_test_flag(VCPU_IN_HYP_CONTEXT) != is_hyp_ctxt(vcpu));
567
568 return __fixup_guest_exit(vcpu, exit_code, hyp_exit_handlers);
569 }
570
571 /* Switch to the guest for VHE systems running in EL2 */
__kvm_vcpu_run_vhe(struct kvm_vcpu * vcpu)572 static int __kvm_vcpu_run_vhe(struct kvm_vcpu *vcpu)
573 {
574 struct kvm_cpu_context *host_ctxt;
575 struct kvm_cpu_context *guest_ctxt;
576 u64 exit_code;
577
578 host_ctxt = host_data_ptr(host_ctxt);
579 guest_ctxt = &vcpu->arch.ctxt;
580
581 fpsimd_lazy_switch_to_guest(vcpu);
582
583 sysreg_save_host_state_vhe(host_ctxt);
584
585 /*
586 * Note that ARM erratum 1165522 requires us to configure both stage 1
587 * and stage 2 translation for the guest context before we clear
588 * HCR_EL2.TGE. The stage 1 and stage 2 guest context has already been
589 * loaded on the CPU in kvm_vcpu_load_vhe().
590 */
591 __activate_traps(vcpu);
592
593 __kvm_adjust_pc(vcpu);
594
595 sysreg_restore_guest_state_vhe(guest_ctxt);
596 __debug_switch_to_guest(vcpu);
597
598 do {
599 /* Jump in the fire! */
600 exit_code = __guest_enter(vcpu);
601
602 /* And we're baaack! */
603 } while (fixup_guest_exit(vcpu, &exit_code));
604
605 sysreg_save_guest_state_vhe(guest_ctxt);
606
607 __deactivate_traps(vcpu);
608
609 sysreg_restore_host_state_vhe(host_ctxt);
610
611 __debug_switch_to_host(vcpu);
612
613 /*
614 * Ensure that all system register writes above have taken effect
615 * before returning to the host. In VHE mode, CPTR traps for
616 * FPSIMD/SVE/SME also apply to EL2, so FPSIMD/SVE/SME state must be
617 * manipulated after the ISB.
618 */
619 isb();
620
621 fpsimd_lazy_switch_to_host(vcpu);
622
623 if (guest_owns_fp_regs())
624 __fpsimd_save_fpexc32(vcpu);
625
626 return exit_code;
627 }
628 NOKPROBE_SYMBOL(__kvm_vcpu_run_vhe);
629
__kvm_vcpu_run(struct kvm_vcpu * vcpu)630 int __kvm_vcpu_run(struct kvm_vcpu *vcpu)
631 {
632 int ret;
633
634 local_daif_mask();
635
636 /*
637 * Having IRQs masked via PMR when entering the guest means the GIC
638 * will not signal the CPU of interrupts of lower priority, and the
639 * only way to get out will be via guest exceptions.
640 * Naturally, we want to avoid this.
641 *
642 * local_daif_mask() already sets GIC_PRIO_PSR_I_SET, we just need a
643 * dsb to ensure the redistributor is forwards EL2 IRQs to the CPU.
644 */
645 pmr_sync();
646
647 ret = __kvm_vcpu_run_vhe(vcpu);
648
649 /*
650 * local_daif_restore() takes care to properly restore PSTATE.DAIF
651 * and the GIC PMR if the host is using IRQ priorities.
652 */
653 local_daif_restore(DAIF_PROCCTX_NOIRQ);
654
655 return ret;
656 }
657
__hyp_call_panic(u64 spsr,u64 elr,u64 par)658 static void __noreturn __hyp_call_panic(u64 spsr, u64 elr, u64 par)
659 {
660 struct kvm_cpu_context *host_ctxt;
661 struct kvm_vcpu *vcpu;
662
663 host_ctxt = host_data_ptr(host_ctxt);
664 vcpu = host_ctxt->__hyp_running_vcpu;
665
666 __deactivate_traps(vcpu);
667 sysreg_restore_host_state_vhe(host_ctxt);
668
669 panic("HYP panic:\nPS:%08llx PC:%016llx ESR:%08llx\nFAR:%016llx HPFAR:%016llx PAR:%016llx\nVCPU:%p\n",
670 spsr, elr,
671 read_sysreg_el2(SYS_ESR), read_sysreg_el2(SYS_FAR),
672 read_sysreg(hpfar_el2), par, vcpu);
673 }
674 NOKPROBE_SYMBOL(__hyp_call_panic);
675
hyp_panic(void)676 void __noreturn hyp_panic(void)
677 {
678 u64 spsr = read_sysreg_el2(SYS_SPSR);
679 u64 elr = read_sysreg_el2(SYS_ELR);
680 u64 par = read_sysreg_par();
681
682 __hyp_call_panic(spsr, elr, par);
683 }
684
kvm_unexpected_el2_exception(void)685 asmlinkage void kvm_unexpected_el2_exception(void)
686 {
687 __kvm_unexpected_el2_exception();
688 }
689