1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Copyright (C) 2012 - Virtual Open Systems and Columbia University
4 * Author: Christoffer Dall <c.dall@virtualopensystems.com>
5 */
6
7 #include <linux/bug.h>
8 #include <linux/cpu_pm.h>
9 #include <linux/entry-kvm.h>
10 #include <linux/errno.h>
11 #include <linux/err.h>
12 #include <linux/kvm_host.h>
13 #include <linux/list.h>
14 #include <linux/module.h>
15 #include <linux/vmalloc.h>
16 #include <linux/fs.h>
17 #include <linux/mman.h>
18 #include <linux/sched.h>
19 #include <linux/kvm.h>
20 #include <linux/kvm_irqfd.h>
21 #include <linux/irqbypass.h>
22 #include <linux/sched/stat.h>
23 #include <linux/psci.h>
24 #include <trace/events/kvm.h>
25
26 #define CREATE_TRACE_POINTS
27 #include "trace_arm.h"
28
29 #include <linux/uaccess.h>
30 #include <asm/ptrace.h>
31 #include <asm/mman.h>
32 #include <asm/tlbflush.h>
33 #include <asm/cacheflush.h>
34 #include <asm/cpufeature.h>
35 #include <asm/virt.h>
36 #include <asm/kvm_arm.h>
37 #include <asm/kvm_asm.h>
38 #include <asm/kvm_emulate.h>
39 #include <asm/kvm_mmu.h>
40 #include <asm/kvm_nested.h>
41 #include <asm/kvm_pkvm.h>
42 #include <asm/kvm_ptrauth.h>
43 #include <asm/sections.h>
44
45 #include <kvm/arm_hypercalls.h>
46 #include <kvm/arm_pmu.h>
47 #include <kvm/arm_psci.h>
48
49 #include "sys_regs.h"
50
51 static enum kvm_mode kvm_mode = KVM_MODE_DEFAULT;
52
53 enum kvm_wfx_trap_policy {
54 KVM_WFX_NOTRAP_SINGLE_TASK, /* Default option */
55 KVM_WFX_NOTRAP,
56 KVM_WFX_TRAP,
57 };
58
59 static enum kvm_wfx_trap_policy kvm_wfi_trap_policy __read_mostly = KVM_WFX_NOTRAP_SINGLE_TASK;
60 static enum kvm_wfx_trap_policy kvm_wfe_trap_policy __read_mostly = KVM_WFX_NOTRAP_SINGLE_TASK;
61
62 DECLARE_KVM_HYP_PER_CPU(unsigned long, kvm_hyp_vector);
63
64 DEFINE_PER_CPU(unsigned long, kvm_arm_hyp_stack_base);
65 DECLARE_KVM_NVHE_PER_CPU(struct kvm_nvhe_init_params, kvm_init_params);
66
67 DECLARE_KVM_NVHE_PER_CPU(struct kvm_cpu_context, kvm_hyp_ctxt);
68
69 static bool vgic_present, kvm_arm_initialised;
70
71 static DEFINE_PER_CPU(unsigned char, kvm_hyp_initialized);
72
is_kvm_arm_initialised(void)73 bool is_kvm_arm_initialised(void)
74 {
75 return kvm_arm_initialised;
76 }
77
kvm_arch_vcpu_should_kick(struct kvm_vcpu * vcpu)78 int kvm_arch_vcpu_should_kick(struct kvm_vcpu *vcpu)
79 {
80 return kvm_vcpu_exiting_guest_mode(vcpu) == IN_GUEST_MODE;
81 }
82
kvm_vm_ioctl_enable_cap(struct kvm * kvm,struct kvm_enable_cap * cap)83 int kvm_vm_ioctl_enable_cap(struct kvm *kvm,
84 struct kvm_enable_cap *cap)
85 {
86 int r = -EINVAL;
87
88 if (cap->flags)
89 return -EINVAL;
90
91 if (kvm_vm_is_protected(kvm) && !kvm_pvm_ext_allowed(cap->cap))
92 return -EINVAL;
93
94 switch (cap->cap) {
95 case KVM_CAP_ARM_NISV_TO_USER:
96 r = 0;
97 set_bit(KVM_ARCH_FLAG_RETURN_NISV_IO_ABORT_TO_USER,
98 &kvm->arch.flags);
99 break;
100 case KVM_CAP_ARM_MTE:
101 mutex_lock(&kvm->lock);
102 if (system_supports_mte() && !kvm->created_vcpus) {
103 r = 0;
104 set_bit(KVM_ARCH_FLAG_MTE_ENABLED, &kvm->arch.flags);
105 }
106 mutex_unlock(&kvm->lock);
107 break;
108 case KVM_CAP_ARM_SYSTEM_SUSPEND:
109 r = 0;
110 set_bit(KVM_ARCH_FLAG_SYSTEM_SUSPEND_ENABLED, &kvm->arch.flags);
111 break;
112 case KVM_CAP_ARM_EAGER_SPLIT_CHUNK_SIZE:
113 mutex_lock(&kvm->slots_lock);
114 /*
115 * To keep things simple, allow changing the chunk
116 * size only when no memory slots have been created.
117 */
118 if (kvm_are_all_memslots_empty(kvm)) {
119 u64 new_cap = cap->args[0];
120
121 if (!new_cap || kvm_is_block_size_supported(new_cap)) {
122 r = 0;
123 kvm->arch.mmu.split_page_chunk_size = new_cap;
124 }
125 }
126 mutex_unlock(&kvm->slots_lock);
127 break;
128 case KVM_CAP_ARM_WRITABLE_IMP_ID_REGS:
129 mutex_lock(&kvm->lock);
130 if (!kvm->created_vcpus) {
131 r = 0;
132 set_bit(KVM_ARCH_FLAG_WRITABLE_IMP_ID_REGS, &kvm->arch.flags);
133 }
134 mutex_unlock(&kvm->lock);
135 break;
136 default:
137 break;
138 }
139
140 return r;
141 }
142
kvm_arm_default_max_vcpus(void)143 static int kvm_arm_default_max_vcpus(void)
144 {
145 return vgic_present ? kvm_vgic_get_max_vcpus() : KVM_MAX_VCPUS;
146 }
147
148 /**
149 * kvm_arch_init_vm - initializes a VM data structure
150 * @kvm: pointer to the KVM struct
151 * @type: kvm device type
152 */
kvm_arch_init_vm(struct kvm * kvm,unsigned long type)153 int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
154 {
155 int ret;
156
157 mutex_init(&kvm->arch.config_lock);
158
159 #ifdef CONFIG_LOCKDEP
160 /* Clue in lockdep that the config_lock must be taken inside kvm->lock */
161 mutex_lock(&kvm->lock);
162 mutex_lock(&kvm->arch.config_lock);
163 mutex_unlock(&kvm->arch.config_lock);
164 mutex_unlock(&kvm->lock);
165 #endif
166
167 kvm_init_nested(kvm);
168
169 ret = kvm_share_hyp(kvm, kvm + 1);
170 if (ret)
171 return ret;
172
173 ret = pkvm_init_host_vm(kvm);
174 if (ret)
175 goto err_unshare_kvm;
176
177 if (!zalloc_cpumask_var(&kvm->arch.supported_cpus, GFP_KERNEL_ACCOUNT)) {
178 ret = -ENOMEM;
179 goto err_unshare_kvm;
180 }
181 cpumask_copy(kvm->arch.supported_cpus, cpu_possible_mask);
182
183 ret = kvm_init_stage2_mmu(kvm, &kvm->arch.mmu, type);
184 if (ret)
185 goto err_free_cpumask;
186
187 kvm_vgic_early_init(kvm);
188
189 kvm_timer_init_vm(kvm);
190
191 /* The maximum number of VCPUs is limited by the host's GIC model */
192 kvm->max_vcpus = kvm_arm_default_max_vcpus();
193
194 kvm_arm_init_hypercalls(kvm);
195
196 bitmap_zero(kvm->arch.vcpu_features, KVM_VCPU_MAX_FEATURES);
197
198 return 0;
199
200 err_free_cpumask:
201 free_cpumask_var(kvm->arch.supported_cpus);
202 err_unshare_kvm:
203 kvm_unshare_hyp(kvm, kvm + 1);
204 return ret;
205 }
206
kvm_arch_vcpu_fault(struct kvm_vcpu * vcpu,struct vm_fault * vmf)207 vm_fault_t kvm_arch_vcpu_fault(struct kvm_vcpu *vcpu, struct vm_fault *vmf)
208 {
209 return VM_FAULT_SIGBUS;
210 }
211
kvm_arch_create_vm_debugfs(struct kvm * kvm)212 void kvm_arch_create_vm_debugfs(struct kvm *kvm)
213 {
214 kvm_sys_regs_create_debugfs(kvm);
215 kvm_s2_ptdump_create_debugfs(kvm);
216 }
217
kvm_destroy_mpidr_data(struct kvm * kvm)218 static void kvm_destroy_mpidr_data(struct kvm *kvm)
219 {
220 struct kvm_mpidr_data *data;
221
222 mutex_lock(&kvm->arch.config_lock);
223
224 data = rcu_dereference_protected(kvm->arch.mpidr_data,
225 lockdep_is_held(&kvm->arch.config_lock));
226 if (data) {
227 rcu_assign_pointer(kvm->arch.mpidr_data, NULL);
228 synchronize_rcu();
229 kfree(data);
230 }
231
232 mutex_unlock(&kvm->arch.config_lock);
233 }
234
235 /**
236 * kvm_arch_destroy_vm - destroy the VM data structure
237 * @kvm: pointer to the KVM struct
238 */
kvm_arch_destroy_vm(struct kvm * kvm)239 void kvm_arch_destroy_vm(struct kvm *kvm)
240 {
241 bitmap_free(kvm->arch.pmu_filter);
242 free_cpumask_var(kvm->arch.supported_cpus);
243
244 kvm_vgic_destroy(kvm);
245
246 if (is_protected_kvm_enabled())
247 pkvm_destroy_hyp_vm(kvm);
248
249 kvm_destroy_mpidr_data(kvm);
250
251 kfree(kvm->arch.sysreg_masks);
252 kvm_destroy_vcpus(kvm);
253
254 kvm_unshare_hyp(kvm, kvm + 1);
255
256 kvm_arm_teardown_hypercalls(kvm);
257 }
258
kvm_has_full_ptr_auth(void)259 static bool kvm_has_full_ptr_auth(void)
260 {
261 bool apa, gpa, api, gpi, apa3, gpa3;
262 u64 isar1, isar2, val;
263
264 /*
265 * Check that:
266 *
267 * - both Address and Generic auth are implemented for a given
268 * algorithm (Q5, IMPDEF or Q3)
269 * - only a single algorithm is implemented.
270 */
271 if (!system_has_full_ptr_auth())
272 return false;
273
274 isar1 = read_sanitised_ftr_reg(SYS_ID_AA64ISAR1_EL1);
275 isar2 = read_sanitised_ftr_reg(SYS_ID_AA64ISAR2_EL1);
276
277 apa = !!FIELD_GET(ID_AA64ISAR1_EL1_APA_MASK, isar1);
278 val = FIELD_GET(ID_AA64ISAR1_EL1_GPA_MASK, isar1);
279 gpa = (val == ID_AA64ISAR1_EL1_GPA_IMP);
280
281 api = !!FIELD_GET(ID_AA64ISAR1_EL1_API_MASK, isar1);
282 val = FIELD_GET(ID_AA64ISAR1_EL1_GPI_MASK, isar1);
283 gpi = (val == ID_AA64ISAR1_EL1_GPI_IMP);
284
285 apa3 = !!FIELD_GET(ID_AA64ISAR2_EL1_APA3_MASK, isar2);
286 val = FIELD_GET(ID_AA64ISAR2_EL1_GPA3_MASK, isar2);
287 gpa3 = (val == ID_AA64ISAR2_EL1_GPA3_IMP);
288
289 return (apa == gpa && api == gpi && apa3 == gpa3 &&
290 (apa + api + apa3) == 1);
291 }
292
kvm_vm_ioctl_check_extension(struct kvm * kvm,long ext)293 int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
294 {
295 int r;
296
297 if (kvm && kvm_vm_is_protected(kvm) && !kvm_pvm_ext_allowed(ext))
298 return 0;
299
300 switch (ext) {
301 case KVM_CAP_IRQCHIP:
302 r = vgic_present;
303 break;
304 case KVM_CAP_IOEVENTFD:
305 case KVM_CAP_USER_MEMORY:
306 case KVM_CAP_SYNC_MMU:
307 case KVM_CAP_DESTROY_MEMORY_REGION_WORKS:
308 case KVM_CAP_ONE_REG:
309 case KVM_CAP_ARM_PSCI:
310 case KVM_CAP_ARM_PSCI_0_2:
311 case KVM_CAP_READONLY_MEM:
312 case KVM_CAP_MP_STATE:
313 case KVM_CAP_IMMEDIATE_EXIT:
314 case KVM_CAP_VCPU_EVENTS:
315 case KVM_CAP_ARM_IRQ_LINE_LAYOUT_2:
316 case KVM_CAP_ARM_NISV_TO_USER:
317 case KVM_CAP_ARM_INJECT_EXT_DABT:
318 case KVM_CAP_SET_GUEST_DEBUG:
319 case KVM_CAP_VCPU_ATTRIBUTES:
320 case KVM_CAP_PTP_KVM:
321 case KVM_CAP_ARM_SYSTEM_SUSPEND:
322 case KVM_CAP_IRQFD_RESAMPLE:
323 case KVM_CAP_COUNTER_OFFSET:
324 case KVM_CAP_ARM_WRITABLE_IMP_ID_REGS:
325 r = 1;
326 break;
327 case KVM_CAP_SET_GUEST_DEBUG2:
328 return KVM_GUESTDBG_VALID_MASK;
329 case KVM_CAP_ARM_SET_DEVICE_ADDR:
330 r = 1;
331 break;
332 case KVM_CAP_NR_VCPUS:
333 /*
334 * ARM64 treats KVM_CAP_NR_CPUS differently from all other
335 * architectures, as it does not always bound it to
336 * KVM_CAP_MAX_VCPUS. It should not matter much because
337 * this is just an advisory value.
338 */
339 r = min_t(unsigned int, num_online_cpus(),
340 kvm_arm_default_max_vcpus());
341 break;
342 case KVM_CAP_MAX_VCPUS:
343 case KVM_CAP_MAX_VCPU_ID:
344 if (kvm)
345 r = kvm->max_vcpus;
346 else
347 r = kvm_arm_default_max_vcpus();
348 break;
349 case KVM_CAP_MSI_DEVID:
350 if (!kvm)
351 r = -EINVAL;
352 else
353 r = kvm->arch.vgic.msis_require_devid;
354 break;
355 case KVM_CAP_ARM_USER_IRQ:
356 /*
357 * 1: EL1_VTIMER, EL1_PTIMER, and PMU.
358 * (bump this number if adding more devices)
359 */
360 r = 1;
361 break;
362 case KVM_CAP_ARM_MTE:
363 r = system_supports_mte();
364 break;
365 case KVM_CAP_STEAL_TIME:
366 r = kvm_arm_pvtime_supported();
367 break;
368 case KVM_CAP_ARM_EL1_32BIT:
369 r = cpus_have_final_cap(ARM64_HAS_32BIT_EL1);
370 break;
371 case KVM_CAP_ARM_EL2:
372 r = cpus_have_final_cap(ARM64_HAS_NESTED_VIRT);
373 break;
374 case KVM_CAP_ARM_EL2_E2H0:
375 r = cpus_have_final_cap(ARM64_HAS_HCR_NV1);
376 break;
377 case KVM_CAP_GUEST_DEBUG_HW_BPS:
378 r = get_num_brps();
379 break;
380 case KVM_CAP_GUEST_DEBUG_HW_WPS:
381 r = get_num_wrps();
382 break;
383 case KVM_CAP_ARM_PMU_V3:
384 r = kvm_supports_guest_pmuv3();
385 break;
386 case KVM_CAP_ARM_INJECT_SERROR_ESR:
387 r = cpus_have_final_cap(ARM64_HAS_RAS_EXTN);
388 break;
389 case KVM_CAP_ARM_VM_IPA_SIZE:
390 r = get_kvm_ipa_limit();
391 break;
392 case KVM_CAP_ARM_SVE:
393 r = system_supports_sve();
394 break;
395 case KVM_CAP_ARM_PTRAUTH_ADDRESS:
396 case KVM_CAP_ARM_PTRAUTH_GENERIC:
397 r = kvm_has_full_ptr_auth();
398 break;
399 case KVM_CAP_ARM_EAGER_SPLIT_CHUNK_SIZE:
400 if (kvm)
401 r = kvm->arch.mmu.split_page_chunk_size;
402 else
403 r = KVM_ARM_EAGER_SPLIT_CHUNK_SIZE_DEFAULT;
404 break;
405 case KVM_CAP_ARM_SUPPORTED_BLOCK_SIZES:
406 r = kvm_supported_block_sizes();
407 break;
408 case KVM_CAP_ARM_SUPPORTED_REG_MASK_RANGES:
409 r = BIT(0);
410 break;
411 case KVM_CAP_ARM_CACHEABLE_PFNMAP_SUPPORTED:
412 if (!kvm)
413 r = -EINVAL;
414 else
415 r = kvm_supports_cacheable_pfnmap();
416 break;
417
418 default:
419 r = 0;
420 }
421
422 return r;
423 }
424
kvm_arch_dev_ioctl(struct file * filp,unsigned int ioctl,unsigned long arg)425 long kvm_arch_dev_ioctl(struct file *filp,
426 unsigned int ioctl, unsigned long arg)
427 {
428 return -EINVAL;
429 }
430
kvm_arch_alloc_vm(void)431 struct kvm *kvm_arch_alloc_vm(void)
432 {
433 size_t sz = sizeof(struct kvm);
434
435 if (!has_vhe())
436 return kzalloc(sz, GFP_KERNEL_ACCOUNT);
437
438 return __vmalloc(sz, GFP_KERNEL_ACCOUNT | __GFP_HIGHMEM | __GFP_ZERO);
439 }
440
kvm_arch_vcpu_precreate(struct kvm * kvm,unsigned int id)441 int kvm_arch_vcpu_precreate(struct kvm *kvm, unsigned int id)
442 {
443 if (irqchip_in_kernel(kvm) && vgic_initialized(kvm))
444 return -EBUSY;
445
446 if (id >= kvm->max_vcpus)
447 return -EINVAL;
448
449 return 0;
450 }
451
kvm_arch_vcpu_create(struct kvm_vcpu * vcpu)452 int kvm_arch_vcpu_create(struct kvm_vcpu *vcpu)
453 {
454 int err;
455
456 spin_lock_init(&vcpu->arch.mp_state_lock);
457
458 #ifdef CONFIG_LOCKDEP
459 /* Inform lockdep that the config_lock is acquired after vcpu->mutex */
460 mutex_lock(&vcpu->mutex);
461 mutex_lock(&vcpu->kvm->arch.config_lock);
462 mutex_unlock(&vcpu->kvm->arch.config_lock);
463 mutex_unlock(&vcpu->mutex);
464 #endif
465
466 /* Force users to call KVM_ARM_VCPU_INIT */
467 vcpu_clear_flag(vcpu, VCPU_INITIALIZED);
468
469 vcpu->arch.mmu_page_cache.gfp_zero = __GFP_ZERO;
470
471 /* Set up the timer */
472 kvm_timer_vcpu_init(vcpu);
473
474 kvm_pmu_vcpu_init(vcpu);
475
476 kvm_arm_pvtime_vcpu_init(&vcpu->arch);
477
478 vcpu->arch.hw_mmu = &vcpu->kvm->arch.mmu;
479
480 /*
481 * This vCPU may have been created after mpidr_data was initialized.
482 * Throw out the pre-computed mappings if that is the case which forces
483 * KVM to fall back to iteratively searching the vCPUs.
484 */
485 kvm_destroy_mpidr_data(vcpu->kvm);
486
487 err = kvm_vgic_vcpu_init(vcpu);
488 if (err)
489 return err;
490
491 err = kvm_share_hyp(vcpu, vcpu + 1);
492 if (err)
493 kvm_vgic_vcpu_destroy(vcpu);
494
495 return err;
496 }
497
kvm_arch_vcpu_postcreate(struct kvm_vcpu * vcpu)498 void kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu)
499 {
500 }
501
kvm_arch_vcpu_destroy(struct kvm_vcpu * vcpu)502 void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu)
503 {
504 if (!is_protected_kvm_enabled())
505 kvm_mmu_free_memory_cache(&vcpu->arch.mmu_page_cache);
506 else
507 free_hyp_memcache(&vcpu->arch.pkvm_memcache);
508 kvm_timer_vcpu_terminate(vcpu);
509 kvm_pmu_vcpu_destroy(vcpu);
510 kvm_vgic_vcpu_destroy(vcpu);
511 kvm_arm_vcpu_destroy(vcpu);
512 }
513
kvm_arch_vcpu_blocking(struct kvm_vcpu * vcpu)514 void kvm_arch_vcpu_blocking(struct kvm_vcpu *vcpu)
515 {
516
517 }
518
kvm_arch_vcpu_unblocking(struct kvm_vcpu * vcpu)519 void kvm_arch_vcpu_unblocking(struct kvm_vcpu *vcpu)
520 {
521
522 }
523
vcpu_set_pauth_traps(struct kvm_vcpu * vcpu)524 static void vcpu_set_pauth_traps(struct kvm_vcpu *vcpu)
525 {
526 if (vcpu_has_ptrauth(vcpu) && !is_protected_kvm_enabled()) {
527 /*
528 * Either we're running an L2 guest, and the API/APK bits come
529 * from L1's HCR_EL2, or API/APK are both set.
530 */
531 if (unlikely(is_nested_ctxt(vcpu))) {
532 u64 val;
533
534 val = __vcpu_sys_reg(vcpu, HCR_EL2);
535 val &= (HCR_API | HCR_APK);
536 vcpu->arch.hcr_el2 &= ~(HCR_API | HCR_APK);
537 vcpu->arch.hcr_el2 |= val;
538 } else {
539 vcpu->arch.hcr_el2 |= (HCR_API | HCR_APK);
540 }
541
542 /*
543 * Save the host keys if there is any chance for the guest
544 * to use pauth, as the entry code will reload the guest
545 * keys in that case.
546 */
547 if (vcpu->arch.hcr_el2 & (HCR_API | HCR_APK)) {
548 struct kvm_cpu_context *ctxt;
549
550 ctxt = this_cpu_ptr_hyp_sym(kvm_hyp_ctxt);
551 ptrauth_save_keys(ctxt);
552 }
553 }
554 }
555
kvm_vcpu_should_clear_twi(struct kvm_vcpu * vcpu)556 static bool kvm_vcpu_should_clear_twi(struct kvm_vcpu *vcpu)
557 {
558 if (unlikely(kvm_wfi_trap_policy != KVM_WFX_NOTRAP_SINGLE_TASK))
559 return kvm_wfi_trap_policy == KVM_WFX_NOTRAP;
560
561 return single_task_running() &&
562 (atomic_read(&vcpu->arch.vgic_cpu.vgic_v3.its_vpe.vlpi_count) ||
563 vcpu->kvm->arch.vgic.nassgireq);
564 }
565
kvm_vcpu_should_clear_twe(struct kvm_vcpu * vcpu)566 static bool kvm_vcpu_should_clear_twe(struct kvm_vcpu *vcpu)
567 {
568 if (unlikely(kvm_wfe_trap_policy != KVM_WFX_NOTRAP_SINGLE_TASK))
569 return kvm_wfe_trap_policy == KVM_WFX_NOTRAP;
570
571 return single_task_running();
572 }
573
kvm_arch_vcpu_load(struct kvm_vcpu * vcpu,int cpu)574 void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
575 {
576 struct kvm_s2_mmu *mmu;
577 int *last_ran;
578
579 if (is_protected_kvm_enabled())
580 goto nommu;
581
582 if (vcpu_has_nv(vcpu))
583 kvm_vcpu_load_hw_mmu(vcpu);
584
585 mmu = vcpu->arch.hw_mmu;
586 last_ran = this_cpu_ptr(mmu->last_vcpu_ran);
587
588 /*
589 * Ensure a VMID is allocated for the MMU before programming VTTBR_EL2,
590 * which happens eagerly in VHE.
591 *
592 * Also, the VMID allocator only preserves VMIDs that are active at the
593 * time of rollover, so KVM might need to grab a new VMID for the MMU if
594 * this is called from kvm_sched_in().
595 */
596 kvm_arm_vmid_update(&mmu->vmid);
597
598 /*
599 * We guarantee that both TLBs and I-cache are private to each
600 * vcpu. If detecting that a vcpu from the same VM has
601 * previously run on the same physical CPU, call into the
602 * hypervisor code to nuke the relevant contexts.
603 *
604 * We might get preempted before the vCPU actually runs, but
605 * over-invalidation doesn't affect correctness.
606 */
607 if (*last_ran != vcpu->vcpu_idx) {
608 kvm_call_hyp(__kvm_flush_cpu_context, mmu);
609 *last_ran = vcpu->vcpu_idx;
610 }
611
612 nommu:
613 vcpu->cpu = cpu;
614
615 /*
616 * The timer must be loaded before the vgic to correctly set up physical
617 * interrupt deactivation in nested state (e.g. timer interrupt).
618 */
619 kvm_timer_vcpu_load(vcpu);
620 kvm_vgic_load(vcpu);
621 kvm_vcpu_load_debug(vcpu);
622 if (has_vhe())
623 kvm_vcpu_load_vhe(vcpu);
624 kvm_arch_vcpu_load_fp(vcpu);
625 kvm_vcpu_pmu_restore_guest(vcpu);
626 if (kvm_arm_is_pvtime_enabled(&vcpu->arch))
627 kvm_make_request(KVM_REQ_RECORD_STEAL, vcpu);
628
629 if (kvm_vcpu_should_clear_twe(vcpu))
630 vcpu->arch.hcr_el2 &= ~HCR_TWE;
631 else
632 vcpu->arch.hcr_el2 |= HCR_TWE;
633
634 if (kvm_vcpu_should_clear_twi(vcpu))
635 vcpu->arch.hcr_el2 &= ~HCR_TWI;
636 else
637 vcpu->arch.hcr_el2 |= HCR_TWI;
638
639 vcpu_set_pauth_traps(vcpu);
640
641 if (is_protected_kvm_enabled()) {
642 kvm_call_hyp_nvhe(__pkvm_vcpu_load,
643 vcpu->kvm->arch.pkvm.handle,
644 vcpu->vcpu_idx, vcpu->arch.hcr_el2);
645 kvm_call_hyp(__vgic_v3_restore_vmcr_aprs,
646 &vcpu->arch.vgic_cpu.vgic_v3);
647 }
648
649 if (!cpumask_test_cpu(cpu, vcpu->kvm->arch.supported_cpus))
650 vcpu_set_on_unsupported_cpu(vcpu);
651 }
652
kvm_arch_vcpu_put(struct kvm_vcpu * vcpu)653 void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu)
654 {
655 if (is_protected_kvm_enabled()) {
656 kvm_call_hyp(__vgic_v3_save_vmcr_aprs,
657 &vcpu->arch.vgic_cpu.vgic_v3);
658 kvm_call_hyp_nvhe(__pkvm_vcpu_put);
659 }
660
661 kvm_vcpu_put_debug(vcpu);
662 kvm_arch_vcpu_put_fp(vcpu);
663 if (has_vhe())
664 kvm_vcpu_put_vhe(vcpu);
665 kvm_timer_vcpu_put(vcpu);
666 kvm_vgic_put(vcpu);
667 kvm_vcpu_pmu_restore_host(vcpu);
668 if (vcpu_has_nv(vcpu))
669 kvm_vcpu_put_hw_mmu(vcpu);
670 kvm_arm_vmid_clear_active();
671
672 vcpu_clear_on_unsupported_cpu(vcpu);
673 vcpu->cpu = -1;
674 }
675
__kvm_arm_vcpu_power_off(struct kvm_vcpu * vcpu)676 static void __kvm_arm_vcpu_power_off(struct kvm_vcpu *vcpu)
677 {
678 WRITE_ONCE(vcpu->arch.mp_state.mp_state, KVM_MP_STATE_STOPPED);
679 kvm_make_request(KVM_REQ_SLEEP, vcpu);
680 kvm_vcpu_kick(vcpu);
681 }
682
kvm_arm_vcpu_power_off(struct kvm_vcpu * vcpu)683 void kvm_arm_vcpu_power_off(struct kvm_vcpu *vcpu)
684 {
685 spin_lock(&vcpu->arch.mp_state_lock);
686 __kvm_arm_vcpu_power_off(vcpu);
687 spin_unlock(&vcpu->arch.mp_state_lock);
688 }
689
kvm_arm_vcpu_stopped(struct kvm_vcpu * vcpu)690 bool kvm_arm_vcpu_stopped(struct kvm_vcpu *vcpu)
691 {
692 return READ_ONCE(vcpu->arch.mp_state.mp_state) == KVM_MP_STATE_STOPPED;
693 }
694
kvm_arm_vcpu_suspend(struct kvm_vcpu * vcpu)695 static void kvm_arm_vcpu_suspend(struct kvm_vcpu *vcpu)
696 {
697 WRITE_ONCE(vcpu->arch.mp_state.mp_state, KVM_MP_STATE_SUSPENDED);
698 kvm_make_request(KVM_REQ_SUSPEND, vcpu);
699 kvm_vcpu_kick(vcpu);
700 }
701
kvm_arm_vcpu_suspended(struct kvm_vcpu * vcpu)702 static bool kvm_arm_vcpu_suspended(struct kvm_vcpu *vcpu)
703 {
704 return READ_ONCE(vcpu->arch.mp_state.mp_state) == KVM_MP_STATE_SUSPENDED;
705 }
706
kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu * vcpu,struct kvm_mp_state * mp_state)707 int kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu *vcpu,
708 struct kvm_mp_state *mp_state)
709 {
710 *mp_state = READ_ONCE(vcpu->arch.mp_state);
711
712 return 0;
713 }
714
kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu * vcpu,struct kvm_mp_state * mp_state)715 int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu,
716 struct kvm_mp_state *mp_state)
717 {
718 int ret = 0;
719
720 spin_lock(&vcpu->arch.mp_state_lock);
721
722 switch (mp_state->mp_state) {
723 case KVM_MP_STATE_RUNNABLE:
724 WRITE_ONCE(vcpu->arch.mp_state, *mp_state);
725 break;
726 case KVM_MP_STATE_STOPPED:
727 __kvm_arm_vcpu_power_off(vcpu);
728 break;
729 case KVM_MP_STATE_SUSPENDED:
730 kvm_arm_vcpu_suspend(vcpu);
731 break;
732 default:
733 ret = -EINVAL;
734 }
735
736 spin_unlock(&vcpu->arch.mp_state_lock);
737
738 return ret;
739 }
740
741 /**
742 * kvm_arch_vcpu_runnable - determine if the vcpu can be scheduled
743 * @v: The VCPU pointer
744 *
745 * If the guest CPU is not waiting for interrupts or an interrupt line is
746 * asserted, the CPU is by definition runnable.
747 */
kvm_arch_vcpu_runnable(struct kvm_vcpu * v)748 int kvm_arch_vcpu_runnable(struct kvm_vcpu *v)
749 {
750 bool irq_lines = *vcpu_hcr(v) & (HCR_VI | HCR_VF | HCR_VSE);
751
752 return ((irq_lines || kvm_vgic_vcpu_pending_irq(v))
753 && !kvm_arm_vcpu_stopped(v) && !v->arch.pause);
754 }
755
kvm_arch_vcpu_in_kernel(struct kvm_vcpu * vcpu)756 bool kvm_arch_vcpu_in_kernel(struct kvm_vcpu *vcpu)
757 {
758 return vcpu_mode_priv(vcpu);
759 }
760
761 #ifdef CONFIG_GUEST_PERF_EVENTS
kvm_arch_vcpu_get_ip(struct kvm_vcpu * vcpu)762 unsigned long kvm_arch_vcpu_get_ip(struct kvm_vcpu *vcpu)
763 {
764 return *vcpu_pc(vcpu);
765 }
766 #endif
767
kvm_init_mpidr_data(struct kvm * kvm)768 static void kvm_init_mpidr_data(struct kvm *kvm)
769 {
770 struct kvm_mpidr_data *data = NULL;
771 unsigned long c, mask, nr_entries;
772 u64 aff_set = 0, aff_clr = ~0UL;
773 struct kvm_vcpu *vcpu;
774
775 mutex_lock(&kvm->arch.config_lock);
776
777 if (rcu_access_pointer(kvm->arch.mpidr_data) ||
778 atomic_read(&kvm->online_vcpus) == 1)
779 goto out;
780
781 kvm_for_each_vcpu(c, vcpu, kvm) {
782 u64 aff = kvm_vcpu_get_mpidr_aff(vcpu);
783 aff_set |= aff;
784 aff_clr &= aff;
785 }
786
787 /*
788 * A significant bit can be either 0 or 1, and will only appear in
789 * aff_set. Use aff_clr to weed out the useless stuff.
790 */
791 mask = aff_set ^ aff_clr;
792 nr_entries = BIT_ULL(hweight_long(mask));
793
794 /*
795 * Don't let userspace fool us. If we need more than a single page
796 * to describe the compressed MPIDR array, just fall back to the
797 * iterative method. Single vcpu VMs do not need this either.
798 */
799 if (struct_size(data, cmpidr_to_idx, nr_entries) <= PAGE_SIZE)
800 data = kzalloc(struct_size(data, cmpidr_to_idx, nr_entries),
801 GFP_KERNEL_ACCOUNT);
802
803 if (!data)
804 goto out;
805
806 data->mpidr_mask = mask;
807
808 kvm_for_each_vcpu(c, vcpu, kvm) {
809 u64 aff = kvm_vcpu_get_mpidr_aff(vcpu);
810 u16 index = kvm_mpidr_index(data, aff);
811
812 data->cmpidr_to_idx[index] = c;
813 }
814
815 rcu_assign_pointer(kvm->arch.mpidr_data, data);
816 out:
817 mutex_unlock(&kvm->arch.config_lock);
818 }
819
820 /*
821 * Handle both the initialisation that is being done when the vcpu is
822 * run for the first time, as well as the updates that must be
823 * performed each time we get a new thread dealing with this vcpu.
824 */
kvm_arch_vcpu_run_pid_change(struct kvm_vcpu * vcpu)825 int kvm_arch_vcpu_run_pid_change(struct kvm_vcpu *vcpu)
826 {
827 struct kvm *kvm = vcpu->kvm;
828 int ret;
829
830 if (!kvm_vcpu_initialized(vcpu))
831 return -ENOEXEC;
832
833 if (!kvm_arm_vcpu_is_finalized(vcpu))
834 return -EPERM;
835
836 if (likely(vcpu_has_run_once(vcpu)))
837 return 0;
838
839 kvm_init_mpidr_data(kvm);
840
841 if (likely(irqchip_in_kernel(kvm))) {
842 /*
843 * Map the VGIC hardware resources before running a vcpu the
844 * first time on this VM.
845 */
846 ret = kvm_vgic_map_resources(kvm);
847 if (ret)
848 return ret;
849 }
850
851 ret = kvm_finalize_sys_regs(vcpu);
852 if (ret)
853 return ret;
854
855 if (vcpu_has_nv(vcpu)) {
856 ret = kvm_vcpu_allocate_vncr_tlb(vcpu);
857 if (ret)
858 return ret;
859
860 ret = kvm_vgic_vcpu_nv_init(vcpu);
861 if (ret)
862 return ret;
863 }
864
865 /*
866 * This needs to happen after any restriction has been applied
867 * to the feature set.
868 */
869 kvm_calculate_traps(vcpu);
870
871 ret = kvm_timer_enable(vcpu);
872 if (ret)
873 return ret;
874
875 if (kvm_vcpu_has_pmu(vcpu)) {
876 ret = kvm_arm_pmu_v3_enable(vcpu);
877 if (ret)
878 return ret;
879 }
880
881 if (is_protected_kvm_enabled()) {
882 ret = pkvm_create_hyp_vm(kvm);
883 if (ret)
884 return ret;
885
886 ret = pkvm_create_hyp_vcpu(vcpu);
887 if (ret)
888 return ret;
889 }
890
891 mutex_lock(&kvm->arch.config_lock);
892 set_bit(KVM_ARCH_FLAG_HAS_RAN_ONCE, &kvm->arch.flags);
893 mutex_unlock(&kvm->arch.config_lock);
894
895 return ret;
896 }
897
kvm_arch_intc_initialized(struct kvm * kvm)898 bool kvm_arch_intc_initialized(struct kvm *kvm)
899 {
900 return vgic_initialized(kvm);
901 }
902
kvm_arm_halt_guest(struct kvm * kvm)903 void kvm_arm_halt_guest(struct kvm *kvm)
904 {
905 unsigned long i;
906 struct kvm_vcpu *vcpu;
907
908 kvm_for_each_vcpu(i, vcpu, kvm)
909 vcpu->arch.pause = true;
910 kvm_make_all_cpus_request(kvm, KVM_REQ_SLEEP);
911 }
912
kvm_arm_resume_guest(struct kvm * kvm)913 void kvm_arm_resume_guest(struct kvm *kvm)
914 {
915 unsigned long i;
916 struct kvm_vcpu *vcpu;
917
918 kvm_for_each_vcpu(i, vcpu, kvm) {
919 vcpu->arch.pause = false;
920 __kvm_vcpu_wake_up(vcpu);
921 }
922 }
923
kvm_vcpu_sleep(struct kvm_vcpu * vcpu)924 static void kvm_vcpu_sleep(struct kvm_vcpu *vcpu)
925 {
926 struct rcuwait *wait = kvm_arch_vcpu_get_wait(vcpu);
927
928 rcuwait_wait_event(wait,
929 (!kvm_arm_vcpu_stopped(vcpu)) && (!vcpu->arch.pause),
930 TASK_INTERRUPTIBLE);
931
932 if (kvm_arm_vcpu_stopped(vcpu) || vcpu->arch.pause) {
933 /* Awaken to handle a signal, request we sleep again later. */
934 kvm_make_request(KVM_REQ_SLEEP, vcpu);
935 }
936
937 /*
938 * Make sure we will observe a potential reset request if we've
939 * observed a change to the power state. Pairs with the smp_wmb() in
940 * kvm_psci_vcpu_on().
941 */
942 smp_rmb();
943 }
944
945 /**
946 * kvm_vcpu_wfi - emulate Wait-For-Interrupt behavior
947 * @vcpu: The VCPU pointer
948 *
949 * Suspend execution of a vCPU until a valid wake event is detected, i.e. until
950 * the vCPU is runnable. The vCPU may or may not be scheduled out, depending
951 * on when a wake event arrives, e.g. there may already be a pending wake event.
952 */
kvm_vcpu_wfi(struct kvm_vcpu * vcpu)953 void kvm_vcpu_wfi(struct kvm_vcpu *vcpu)
954 {
955 /*
956 * Sync back the state of the GIC CPU interface so that we have
957 * the latest PMR and group enables. This ensures that
958 * kvm_arch_vcpu_runnable has up-to-date data to decide whether
959 * we have pending interrupts, e.g. when determining if the
960 * vCPU should block.
961 *
962 * For the same reason, we want to tell GICv4 that we need
963 * doorbells to be signalled, should an interrupt become pending.
964 */
965 preempt_disable();
966 vcpu_set_flag(vcpu, IN_WFI);
967 kvm_vgic_put(vcpu);
968 preempt_enable();
969
970 kvm_vcpu_halt(vcpu);
971 vcpu_clear_flag(vcpu, IN_WFIT);
972
973 preempt_disable();
974 vcpu_clear_flag(vcpu, IN_WFI);
975 kvm_vgic_load(vcpu);
976 preempt_enable();
977 }
978
kvm_vcpu_suspend(struct kvm_vcpu * vcpu)979 static int kvm_vcpu_suspend(struct kvm_vcpu *vcpu)
980 {
981 if (!kvm_arm_vcpu_suspended(vcpu))
982 return 1;
983
984 kvm_vcpu_wfi(vcpu);
985
986 /*
987 * The suspend state is sticky; we do not leave it until userspace
988 * explicitly marks the vCPU as runnable. Request that we suspend again
989 * later.
990 */
991 kvm_make_request(KVM_REQ_SUSPEND, vcpu);
992
993 /*
994 * Check to make sure the vCPU is actually runnable. If so, exit to
995 * userspace informing it of the wakeup condition.
996 */
997 if (kvm_arch_vcpu_runnable(vcpu)) {
998 memset(&vcpu->run->system_event, 0, sizeof(vcpu->run->system_event));
999 vcpu->run->system_event.type = KVM_SYSTEM_EVENT_WAKEUP;
1000 vcpu->run->exit_reason = KVM_EXIT_SYSTEM_EVENT;
1001 return 0;
1002 }
1003
1004 /*
1005 * Otherwise, we were unblocked to process a different event, such as a
1006 * pending signal. Return 1 and allow kvm_arch_vcpu_ioctl_run() to
1007 * process the event.
1008 */
1009 return 1;
1010 }
1011
1012 /**
1013 * check_vcpu_requests - check and handle pending vCPU requests
1014 * @vcpu: the VCPU pointer
1015 *
1016 * Return: 1 if we should enter the guest
1017 * 0 if we should exit to userspace
1018 * < 0 if we should exit to userspace, where the return value indicates
1019 * an error
1020 */
check_vcpu_requests(struct kvm_vcpu * vcpu)1021 static int check_vcpu_requests(struct kvm_vcpu *vcpu)
1022 {
1023 if (kvm_request_pending(vcpu)) {
1024 if (kvm_check_request(KVM_REQ_VM_DEAD, vcpu))
1025 return -EIO;
1026
1027 if (kvm_check_request(KVM_REQ_SLEEP, vcpu))
1028 kvm_vcpu_sleep(vcpu);
1029
1030 if (kvm_check_request(KVM_REQ_VCPU_RESET, vcpu))
1031 kvm_reset_vcpu(vcpu);
1032
1033 /*
1034 * Clear IRQ_PENDING requests that were made to guarantee
1035 * that a VCPU sees new virtual interrupts.
1036 */
1037 kvm_check_request(KVM_REQ_IRQ_PENDING, vcpu);
1038
1039 if (kvm_check_request(KVM_REQ_RECORD_STEAL, vcpu))
1040 kvm_update_stolen_time(vcpu);
1041
1042 if (kvm_check_request(KVM_REQ_RELOAD_GICv4, vcpu)) {
1043 /* The distributor enable bits were changed */
1044 preempt_disable();
1045 vgic_v4_put(vcpu);
1046 vgic_v4_load(vcpu);
1047 preempt_enable();
1048 }
1049
1050 if (kvm_check_request(KVM_REQ_RELOAD_PMU, vcpu))
1051 kvm_vcpu_reload_pmu(vcpu);
1052
1053 if (kvm_check_request(KVM_REQ_RESYNC_PMU_EL0, vcpu))
1054 kvm_vcpu_pmu_restore_guest(vcpu);
1055
1056 if (kvm_check_request(KVM_REQ_SUSPEND, vcpu))
1057 return kvm_vcpu_suspend(vcpu);
1058
1059 if (kvm_dirty_ring_check_request(vcpu))
1060 return 0;
1061
1062 check_nested_vcpu_requests(vcpu);
1063 }
1064
1065 return 1;
1066 }
1067
vcpu_mode_is_bad_32bit(struct kvm_vcpu * vcpu)1068 static bool vcpu_mode_is_bad_32bit(struct kvm_vcpu *vcpu)
1069 {
1070 if (likely(!vcpu_mode_is_32bit(vcpu)))
1071 return false;
1072
1073 if (vcpu_has_nv(vcpu))
1074 return true;
1075
1076 return !kvm_supports_32bit_el0();
1077 }
1078
1079 /**
1080 * kvm_vcpu_exit_request - returns true if the VCPU should *not* enter the guest
1081 * @vcpu: The VCPU pointer
1082 * @ret: Pointer to write optional return code
1083 *
1084 * Returns: true if the VCPU needs to return to a preemptible + interruptible
1085 * and skip guest entry.
1086 *
1087 * This function disambiguates between two different types of exits: exits to a
1088 * preemptible + interruptible kernel context and exits to userspace. For an
1089 * exit to userspace, this function will write the return code to ret and return
1090 * true. For an exit to preemptible + interruptible kernel context (i.e. check
1091 * for pending work and re-enter), return true without writing to ret.
1092 */
kvm_vcpu_exit_request(struct kvm_vcpu * vcpu,int * ret)1093 static bool kvm_vcpu_exit_request(struct kvm_vcpu *vcpu, int *ret)
1094 {
1095 struct kvm_run *run = vcpu->run;
1096
1097 /*
1098 * If we're using a userspace irqchip, then check if we need
1099 * to tell a userspace irqchip about timer or PMU level
1100 * changes and if so, exit to userspace (the actual level
1101 * state gets updated in kvm_timer_update_run and
1102 * kvm_pmu_update_run below).
1103 */
1104 if (unlikely(!irqchip_in_kernel(vcpu->kvm))) {
1105 if (kvm_timer_should_notify_user(vcpu) ||
1106 kvm_pmu_should_notify_user(vcpu)) {
1107 *ret = -EINTR;
1108 run->exit_reason = KVM_EXIT_INTR;
1109 return true;
1110 }
1111 }
1112
1113 if (unlikely(vcpu_on_unsupported_cpu(vcpu))) {
1114 run->exit_reason = KVM_EXIT_FAIL_ENTRY;
1115 run->fail_entry.hardware_entry_failure_reason = KVM_EXIT_FAIL_ENTRY_CPU_UNSUPPORTED;
1116 run->fail_entry.cpu = smp_processor_id();
1117 *ret = 0;
1118 return true;
1119 }
1120
1121 return kvm_request_pending(vcpu) ||
1122 xfer_to_guest_mode_work_pending();
1123 }
1124
1125 /*
1126 * Actually run the vCPU, entering an RCU extended quiescent state (EQS) while
1127 * the vCPU is running.
1128 *
1129 * This must be noinstr as instrumentation may make use of RCU, and this is not
1130 * safe during the EQS.
1131 */
kvm_arm_vcpu_enter_exit(struct kvm_vcpu * vcpu)1132 static int noinstr kvm_arm_vcpu_enter_exit(struct kvm_vcpu *vcpu)
1133 {
1134 int ret;
1135
1136 guest_state_enter_irqoff();
1137 ret = kvm_call_hyp_ret(__kvm_vcpu_run, vcpu);
1138 guest_state_exit_irqoff();
1139
1140 return ret;
1141 }
1142
1143 /**
1144 * kvm_arch_vcpu_ioctl_run - the main VCPU run function to execute guest code
1145 * @vcpu: The VCPU pointer
1146 *
1147 * This function is called through the VCPU_RUN ioctl called from user space. It
1148 * will execute VM code in a loop until the time slice for the process is used
1149 * or some emulation is needed from user space in which case the function will
1150 * return with return value 0 and with the kvm_run structure filled in with the
1151 * required data for the requested emulation.
1152 */
kvm_arch_vcpu_ioctl_run(struct kvm_vcpu * vcpu)1153 int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu)
1154 {
1155 struct kvm_run *run = vcpu->run;
1156 int ret;
1157
1158 if (run->exit_reason == KVM_EXIT_MMIO) {
1159 ret = kvm_handle_mmio_return(vcpu);
1160 if (ret <= 0)
1161 return ret;
1162 }
1163
1164 vcpu_load(vcpu);
1165
1166 if (!vcpu->wants_to_run) {
1167 ret = -EINTR;
1168 goto out;
1169 }
1170
1171 kvm_sigset_activate(vcpu);
1172
1173 ret = 1;
1174 run->exit_reason = KVM_EXIT_UNKNOWN;
1175 run->flags = 0;
1176 while (ret > 0) {
1177 /*
1178 * Check conditions before entering the guest
1179 */
1180 ret = xfer_to_guest_mode_handle_work(vcpu);
1181 if (!ret)
1182 ret = 1;
1183
1184 if (ret > 0)
1185 ret = check_vcpu_requests(vcpu);
1186
1187 /*
1188 * Preparing the interrupts to be injected also
1189 * involves poking the GIC, which must be done in a
1190 * non-preemptible context.
1191 */
1192 preempt_disable();
1193
1194 kvm_nested_flush_hwstate(vcpu);
1195
1196 if (kvm_vcpu_has_pmu(vcpu))
1197 kvm_pmu_flush_hwstate(vcpu);
1198
1199 local_irq_disable();
1200
1201 kvm_vgic_flush_hwstate(vcpu);
1202
1203 kvm_pmu_update_vcpu_events(vcpu);
1204
1205 /*
1206 * Ensure we set mode to IN_GUEST_MODE after we disable
1207 * interrupts and before the final VCPU requests check.
1208 * See the comment in kvm_vcpu_exiting_guest_mode() and
1209 * Documentation/virt/kvm/vcpu-requests.rst
1210 */
1211 smp_store_mb(vcpu->mode, IN_GUEST_MODE);
1212
1213 if (ret <= 0 || kvm_vcpu_exit_request(vcpu, &ret)) {
1214 vcpu->mode = OUTSIDE_GUEST_MODE;
1215 isb(); /* Ensure work in x_flush_hwstate is committed */
1216 if (kvm_vcpu_has_pmu(vcpu))
1217 kvm_pmu_sync_hwstate(vcpu);
1218 if (unlikely(!irqchip_in_kernel(vcpu->kvm)))
1219 kvm_timer_sync_user(vcpu);
1220 kvm_vgic_sync_hwstate(vcpu);
1221 local_irq_enable();
1222 preempt_enable();
1223 continue;
1224 }
1225
1226 kvm_arch_vcpu_ctxflush_fp(vcpu);
1227
1228 /**************************************************************
1229 * Enter the guest
1230 */
1231 trace_kvm_entry(*vcpu_pc(vcpu));
1232 guest_timing_enter_irqoff();
1233
1234 ret = kvm_arm_vcpu_enter_exit(vcpu);
1235
1236 vcpu->mode = OUTSIDE_GUEST_MODE;
1237 vcpu->stat.exits++;
1238 /*
1239 * Back from guest
1240 *************************************************************/
1241
1242 /*
1243 * We must sync the PMU state before the vgic state so
1244 * that the vgic can properly sample the updated state of the
1245 * interrupt line.
1246 */
1247 if (kvm_vcpu_has_pmu(vcpu))
1248 kvm_pmu_sync_hwstate(vcpu);
1249
1250 /*
1251 * Sync the vgic state before syncing the timer state because
1252 * the timer code needs to know if the virtual timer
1253 * interrupts are active.
1254 */
1255 kvm_vgic_sync_hwstate(vcpu);
1256
1257 /*
1258 * Sync the timer hardware state before enabling interrupts as
1259 * we don't want vtimer interrupts to race with syncing the
1260 * timer virtual interrupt state.
1261 */
1262 if (unlikely(!irqchip_in_kernel(vcpu->kvm)))
1263 kvm_timer_sync_user(vcpu);
1264
1265 if (is_hyp_ctxt(vcpu))
1266 kvm_timer_sync_nested(vcpu);
1267
1268 kvm_arch_vcpu_ctxsync_fp(vcpu);
1269
1270 /*
1271 * We must ensure that any pending interrupts are taken before
1272 * we exit guest timing so that timer ticks are accounted as
1273 * guest time. Transiently unmask interrupts so that any
1274 * pending interrupts are taken.
1275 *
1276 * Per ARM DDI 0487G.b section D1.13.4, an ISB (or other
1277 * context synchronization event) is necessary to ensure that
1278 * pending interrupts are taken.
1279 */
1280 if (ARM_EXCEPTION_CODE(ret) == ARM_EXCEPTION_IRQ) {
1281 local_irq_enable();
1282 isb();
1283 local_irq_disable();
1284 }
1285
1286 guest_timing_exit_irqoff();
1287
1288 local_irq_enable();
1289
1290 trace_kvm_exit(ret, kvm_vcpu_trap_get_class(vcpu), *vcpu_pc(vcpu));
1291
1292 /* Exit types that need handling before we can be preempted */
1293 handle_exit_early(vcpu, ret);
1294
1295 kvm_nested_sync_hwstate(vcpu);
1296
1297 preempt_enable();
1298
1299 /*
1300 * The ARMv8 architecture doesn't give the hypervisor
1301 * a mechanism to prevent a guest from dropping to AArch32 EL0
1302 * if implemented by the CPU. If we spot the guest in such
1303 * state and that we decided it wasn't supposed to do so (like
1304 * with the asymmetric AArch32 case), return to userspace with
1305 * a fatal error.
1306 */
1307 if (vcpu_mode_is_bad_32bit(vcpu)) {
1308 /*
1309 * As we have caught the guest red-handed, decide that
1310 * it isn't fit for purpose anymore by making the vcpu
1311 * invalid. The VMM can try and fix it by issuing a
1312 * KVM_ARM_VCPU_INIT if it really wants to.
1313 */
1314 vcpu_clear_flag(vcpu, VCPU_INITIALIZED);
1315 ret = ARM_EXCEPTION_IL;
1316 }
1317
1318 ret = handle_exit(vcpu, ret);
1319 }
1320
1321 /* Tell userspace about in-kernel device output levels */
1322 if (unlikely(!irqchip_in_kernel(vcpu->kvm))) {
1323 kvm_timer_update_run(vcpu);
1324 kvm_pmu_update_run(vcpu);
1325 }
1326
1327 kvm_sigset_deactivate(vcpu);
1328
1329 out:
1330 /*
1331 * In the unlikely event that we are returning to userspace
1332 * with pending exceptions or PC adjustment, commit these
1333 * adjustments in order to give userspace a consistent view of
1334 * the vcpu state. Note that this relies on __kvm_adjust_pc()
1335 * being preempt-safe on VHE.
1336 */
1337 if (unlikely(vcpu_get_flag(vcpu, PENDING_EXCEPTION) ||
1338 vcpu_get_flag(vcpu, INCREMENT_PC)))
1339 kvm_call_hyp(__kvm_adjust_pc, vcpu);
1340
1341 vcpu_put(vcpu);
1342 return ret;
1343 }
1344
vcpu_interrupt_line(struct kvm_vcpu * vcpu,int number,bool level)1345 static int vcpu_interrupt_line(struct kvm_vcpu *vcpu, int number, bool level)
1346 {
1347 int bit_index;
1348 bool set;
1349 unsigned long *hcr;
1350
1351 if (number == KVM_ARM_IRQ_CPU_IRQ)
1352 bit_index = __ffs(HCR_VI);
1353 else /* KVM_ARM_IRQ_CPU_FIQ */
1354 bit_index = __ffs(HCR_VF);
1355
1356 hcr = vcpu_hcr(vcpu);
1357 if (level)
1358 set = test_and_set_bit(bit_index, hcr);
1359 else
1360 set = test_and_clear_bit(bit_index, hcr);
1361
1362 /*
1363 * If we didn't change anything, no need to wake up or kick other CPUs
1364 */
1365 if (set == level)
1366 return 0;
1367
1368 /*
1369 * The vcpu irq_lines field was updated, wake up sleeping VCPUs and
1370 * trigger a world-switch round on the running physical CPU to set the
1371 * virtual IRQ/FIQ fields in the HCR appropriately.
1372 */
1373 kvm_make_request(KVM_REQ_IRQ_PENDING, vcpu);
1374 kvm_vcpu_kick(vcpu);
1375
1376 return 0;
1377 }
1378
kvm_vm_ioctl_irq_line(struct kvm * kvm,struct kvm_irq_level * irq_level,bool line_status)1379 int kvm_vm_ioctl_irq_line(struct kvm *kvm, struct kvm_irq_level *irq_level,
1380 bool line_status)
1381 {
1382 u32 irq = irq_level->irq;
1383 unsigned int irq_type, vcpu_id, irq_num;
1384 struct kvm_vcpu *vcpu = NULL;
1385 bool level = irq_level->level;
1386
1387 irq_type = (irq >> KVM_ARM_IRQ_TYPE_SHIFT) & KVM_ARM_IRQ_TYPE_MASK;
1388 vcpu_id = (irq >> KVM_ARM_IRQ_VCPU_SHIFT) & KVM_ARM_IRQ_VCPU_MASK;
1389 vcpu_id += ((irq >> KVM_ARM_IRQ_VCPU2_SHIFT) & KVM_ARM_IRQ_VCPU2_MASK) * (KVM_ARM_IRQ_VCPU_MASK + 1);
1390 irq_num = (irq >> KVM_ARM_IRQ_NUM_SHIFT) & KVM_ARM_IRQ_NUM_MASK;
1391
1392 trace_kvm_irq_line(irq_type, vcpu_id, irq_num, irq_level->level);
1393
1394 switch (irq_type) {
1395 case KVM_ARM_IRQ_TYPE_CPU:
1396 if (irqchip_in_kernel(kvm))
1397 return -ENXIO;
1398
1399 vcpu = kvm_get_vcpu_by_id(kvm, vcpu_id);
1400 if (!vcpu)
1401 return -EINVAL;
1402
1403 if (irq_num > KVM_ARM_IRQ_CPU_FIQ)
1404 return -EINVAL;
1405
1406 return vcpu_interrupt_line(vcpu, irq_num, level);
1407 case KVM_ARM_IRQ_TYPE_PPI:
1408 if (!irqchip_in_kernel(kvm))
1409 return -ENXIO;
1410
1411 vcpu = kvm_get_vcpu_by_id(kvm, vcpu_id);
1412 if (!vcpu)
1413 return -EINVAL;
1414
1415 if (irq_num < VGIC_NR_SGIS || irq_num >= VGIC_NR_PRIVATE_IRQS)
1416 return -EINVAL;
1417
1418 return kvm_vgic_inject_irq(kvm, vcpu, irq_num, level, NULL);
1419 case KVM_ARM_IRQ_TYPE_SPI:
1420 if (!irqchip_in_kernel(kvm))
1421 return -ENXIO;
1422
1423 if (irq_num < VGIC_NR_PRIVATE_IRQS)
1424 return -EINVAL;
1425
1426 return kvm_vgic_inject_irq(kvm, NULL, irq_num, level, NULL);
1427 }
1428
1429 return -EINVAL;
1430 }
1431
system_supported_vcpu_features(void)1432 static unsigned long system_supported_vcpu_features(void)
1433 {
1434 unsigned long features = KVM_VCPU_VALID_FEATURES;
1435
1436 if (!cpus_have_final_cap(ARM64_HAS_32BIT_EL1))
1437 clear_bit(KVM_ARM_VCPU_EL1_32BIT, &features);
1438
1439 if (!kvm_supports_guest_pmuv3())
1440 clear_bit(KVM_ARM_VCPU_PMU_V3, &features);
1441
1442 if (!system_supports_sve())
1443 clear_bit(KVM_ARM_VCPU_SVE, &features);
1444
1445 if (!kvm_has_full_ptr_auth()) {
1446 clear_bit(KVM_ARM_VCPU_PTRAUTH_ADDRESS, &features);
1447 clear_bit(KVM_ARM_VCPU_PTRAUTH_GENERIC, &features);
1448 }
1449
1450 if (!cpus_have_final_cap(ARM64_HAS_NESTED_VIRT))
1451 clear_bit(KVM_ARM_VCPU_HAS_EL2, &features);
1452
1453 return features;
1454 }
1455
kvm_vcpu_init_check_features(struct kvm_vcpu * vcpu,const struct kvm_vcpu_init * init)1456 static int kvm_vcpu_init_check_features(struct kvm_vcpu *vcpu,
1457 const struct kvm_vcpu_init *init)
1458 {
1459 unsigned long features = init->features[0];
1460 int i;
1461
1462 if (features & ~KVM_VCPU_VALID_FEATURES)
1463 return -ENOENT;
1464
1465 for (i = 1; i < ARRAY_SIZE(init->features); i++) {
1466 if (init->features[i])
1467 return -ENOENT;
1468 }
1469
1470 if (features & ~system_supported_vcpu_features())
1471 return -EINVAL;
1472
1473 /*
1474 * For now make sure that both address/generic pointer authentication
1475 * features are requested by the userspace together.
1476 */
1477 if (test_bit(KVM_ARM_VCPU_PTRAUTH_ADDRESS, &features) !=
1478 test_bit(KVM_ARM_VCPU_PTRAUTH_GENERIC, &features))
1479 return -EINVAL;
1480
1481 if (!test_bit(KVM_ARM_VCPU_EL1_32BIT, &features))
1482 return 0;
1483
1484 /* MTE is incompatible with AArch32 */
1485 if (kvm_has_mte(vcpu->kvm))
1486 return -EINVAL;
1487
1488 /* NV is incompatible with AArch32 */
1489 if (test_bit(KVM_ARM_VCPU_HAS_EL2, &features))
1490 return -EINVAL;
1491
1492 return 0;
1493 }
1494
kvm_vcpu_init_changed(struct kvm_vcpu * vcpu,const struct kvm_vcpu_init * init)1495 static bool kvm_vcpu_init_changed(struct kvm_vcpu *vcpu,
1496 const struct kvm_vcpu_init *init)
1497 {
1498 unsigned long features = init->features[0];
1499
1500 return !bitmap_equal(vcpu->kvm->arch.vcpu_features, &features,
1501 KVM_VCPU_MAX_FEATURES);
1502 }
1503
kvm_setup_vcpu(struct kvm_vcpu * vcpu)1504 static int kvm_setup_vcpu(struct kvm_vcpu *vcpu)
1505 {
1506 struct kvm *kvm = vcpu->kvm;
1507 int ret = 0;
1508
1509 /*
1510 * When the vCPU has a PMU, but no PMU is set for the guest
1511 * yet, set the default one.
1512 */
1513 if (kvm_vcpu_has_pmu(vcpu) && !kvm->arch.arm_pmu)
1514 ret = kvm_arm_set_default_pmu(kvm);
1515
1516 /* Prepare for nested if required */
1517 if (!ret && vcpu_has_nv(vcpu))
1518 ret = kvm_vcpu_init_nested(vcpu);
1519
1520 return ret;
1521 }
1522
__kvm_vcpu_set_target(struct kvm_vcpu * vcpu,const struct kvm_vcpu_init * init)1523 static int __kvm_vcpu_set_target(struct kvm_vcpu *vcpu,
1524 const struct kvm_vcpu_init *init)
1525 {
1526 unsigned long features = init->features[0];
1527 struct kvm *kvm = vcpu->kvm;
1528 int ret = -EINVAL;
1529
1530 mutex_lock(&kvm->arch.config_lock);
1531
1532 if (test_bit(KVM_ARCH_FLAG_VCPU_FEATURES_CONFIGURED, &kvm->arch.flags) &&
1533 kvm_vcpu_init_changed(vcpu, init))
1534 goto out_unlock;
1535
1536 bitmap_copy(kvm->arch.vcpu_features, &features, KVM_VCPU_MAX_FEATURES);
1537
1538 ret = kvm_setup_vcpu(vcpu);
1539 if (ret)
1540 goto out_unlock;
1541
1542 /* Now we know what it is, we can reset it. */
1543 kvm_reset_vcpu(vcpu);
1544
1545 set_bit(KVM_ARCH_FLAG_VCPU_FEATURES_CONFIGURED, &kvm->arch.flags);
1546 vcpu_set_flag(vcpu, VCPU_INITIALIZED);
1547 ret = 0;
1548 out_unlock:
1549 mutex_unlock(&kvm->arch.config_lock);
1550 return ret;
1551 }
1552
kvm_vcpu_set_target(struct kvm_vcpu * vcpu,const struct kvm_vcpu_init * init)1553 static int kvm_vcpu_set_target(struct kvm_vcpu *vcpu,
1554 const struct kvm_vcpu_init *init)
1555 {
1556 int ret;
1557
1558 if (init->target != KVM_ARM_TARGET_GENERIC_V8 &&
1559 init->target != kvm_target_cpu())
1560 return -EINVAL;
1561
1562 ret = kvm_vcpu_init_check_features(vcpu, init);
1563 if (ret)
1564 return ret;
1565
1566 if (!kvm_vcpu_initialized(vcpu))
1567 return __kvm_vcpu_set_target(vcpu, init);
1568
1569 if (kvm_vcpu_init_changed(vcpu, init))
1570 return -EINVAL;
1571
1572 kvm_reset_vcpu(vcpu);
1573 return 0;
1574 }
1575
kvm_arch_vcpu_ioctl_vcpu_init(struct kvm_vcpu * vcpu,struct kvm_vcpu_init * init)1576 static int kvm_arch_vcpu_ioctl_vcpu_init(struct kvm_vcpu *vcpu,
1577 struct kvm_vcpu_init *init)
1578 {
1579 bool power_off = false;
1580 int ret;
1581
1582 /*
1583 * Treat the power-off vCPU feature as ephemeral. Clear the bit to avoid
1584 * reflecting it in the finalized feature set, thus limiting its scope
1585 * to a single KVM_ARM_VCPU_INIT call.
1586 */
1587 if (init->features[0] & BIT(KVM_ARM_VCPU_POWER_OFF)) {
1588 init->features[0] &= ~BIT(KVM_ARM_VCPU_POWER_OFF);
1589 power_off = true;
1590 }
1591
1592 ret = kvm_vcpu_set_target(vcpu, init);
1593 if (ret)
1594 return ret;
1595
1596 /*
1597 * Ensure a rebooted VM will fault in RAM pages and detect if the
1598 * guest MMU is turned off and flush the caches as needed.
1599 *
1600 * S2FWB enforces all memory accesses to RAM being cacheable,
1601 * ensuring that the data side is always coherent. We still
1602 * need to invalidate the I-cache though, as FWB does *not*
1603 * imply CTR_EL0.DIC.
1604 */
1605 if (vcpu_has_run_once(vcpu)) {
1606 if (!cpus_have_final_cap(ARM64_HAS_STAGE2_FWB))
1607 stage2_unmap_vm(vcpu->kvm);
1608 else
1609 icache_inval_all_pou();
1610 }
1611
1612 vcpu_reset_hcr(vcpu);
1613
1614 /*
1615 * Handle the "start in power-off" case.
1616 */
1617 spin_lock(&vcpu->arch.mp_state_lock);
1618
1619 if (power_off)
1620 __kvm_arm_vcpu_power_off(vcpu);
1621 else
1622 WRITE_ONCE(vcpu->arch.mp_state.mp_state, KVM_MP_STATE_RUNNABLE);
1623
1624 spin_unlock(&vcpu->arch.mp_state_lock);
1625
1626 return 0;
1627 }
1628
kvm_arm_vcpu_set_attr(struct kvm_vcpu * vcpu,struct kvm_device_attr * attr)1629 static int kvm_arm_vcpu_set_attr(struct kvm_vcpu *vcpu,
1630 struct kvm_device_attr *attr)
1631 {
1632 int ret = -ENXIO;
1633
1634 switch (attr->group) {
1635 default:
1636 ret = kvm_arm_vcpu_arch_set_attr(vcpu, attr);
1637 break;
1638 }
1639
1640 return ret;
1641 }
1642
kvm_arm_vcpu_get_attr(struct kvm_vcpu * vcpu,struct kvm_device_attr * attr)1643 static int kvm_arm_vcpu_get_attr(struct kvm_vcpu *vcpu,
1644 struct kvm_device_attr *attr)
1645 {
1646 int ret = -ENXIO;
1647
1648 switch (attr->group) {
1649 default:
1650 ret = kvm_arm_vcpu_arch_get_attr(vcpu, attr);
1651 break;
1652 }
1653
1654 return ret;
1655 }
1656
kvm_arm_vcpu_has_attr(struct kvm_vcpu * vcpu,struct kvm_device_attr * attr)1657 static int kvm_arm_vcpu_has_attr(struct kvm_vcpu *vcpu,
1658 struct kvm_device_attr *attr)
1659 {
1660 int ret = -ENXIO;
1661
1662 switch (attr->group) {
1663 default:
1664 ret = kvm_arm_vcpu_arch_has_attr(vcpu, attr);
1665 break;
1666 }
1667
1668 return ret;
1669 }
1670
kvm_arm_vcpu_get_events(struct kvm_vcpu * vcpu,struct kvm_vcpu_events * events)1671 static int kvm_arm_vcpu_get_events(struct kvm_vcpu *vcpu,
1672 struct kvm_vcpu_events *events)
1673 {
1674 memset(events, 0, sizeof(*events));
1675
1676 return __kvm_arm_vcpu_get_events(vcpu, events);
1677 }
1678
kvm_arm_vcpu_set_events(struct kvm_vcpu * vcpu,struct kvm_vcpu_events * events)1679 static int kvm_arm_vcpu_set_events(struct kvm_vcpu *vcpu,
1680 struct kvm_vcpu_events *events)
1681 {
1682 int i;
1683
1684 /* check whether the reserved field is zero */
1685 for (i = 0; i < ARRAY_SIZE(events->reserved); i++)
1686 if (events->reserved[i])
1687 return -EINVAL;
1688
1689 /* check whether the pad field is zero */
1690 for (i = 0; i < ARRAY_SIZE(events->exception.pad); i++)
1691 if (events->exception.pad[i])
1692 return -EINVAL;
1693
1694 return __kvm_arm_vcpu_set_events(vcpu, events);
1695 }
1696
kvm_arch_vcpu_ioctl(struct file * filp,unsigned int ioctl,unsigned long arg)1697 long kvm_arch_vcpu_ioctl(struct file *filp,
1698 unsigned int ioctl, unsigned long arg)
1699 {
1700 struct kvm_vcpu *vcpu = filp->private_data;
1701 void __user *argp = (void __user *)arg;
1702 struct kvm_device_attr attr;
1703 long r;
1704
1705 switch (ioctl) {
1706 case KVM_ARM_VCPU_INIT: {
1707 struct kvm_vcpu_init init;
1708
1709 r = -EFAULT;
1710 if (copy_from_user(&init, argp, sizeof(init)))
1711 break;
1712
1713 r = kvm_arch_vcpu_ioctl_vcpu_init(vcpu, &init);
1714 break;
1715 }
1716 case KVM_SET_ONE_REG:
1717 case KVM_GET_ONE_REG: {
1718 struct kvm_one_reg reg;
1719
1720 r = -ENOEXEC;
1721 if (unlikely(!kvm_vcpu_initialized(vcpu)))
1722 break;
1723
1724 r = -EFAULT;
1725 if (copy_from_user(®, argp, sizeof(reg)))
1726 break;
1727
1728 /*
1729 * We could owe a reset due to PSCI. Handle the pending reset
1730 * here to ensure userspace register accesses are ordered after
1731 * the reset.
1732 */
1733 if (kvm_check_request(KVM_REQ_VCPU_RESET, vcpu))
1734 kvm_reset_vcpu(vcpu);
1735
1736 if (ioctl == KVM_SET_ONE_REG)
1737 r = kvm_arm_set_reg(vcpu, ®);
1738 else
1739 r = kvm_arm_get_reg(vcpu, ®);
1740 break;
1741 }
1742 case KVM_GET_REG_LIST: {
1743 struct kvm_reg_list __user *user_list = argp;
1744 struct kvm_reg_list reg_list;
1745 unsigned n;
1746
1747 r = -ENOEXEC;
1748 if (unlikely(!kvm_vcpu_initialized(vcpu)))
1749 break;
1750
1751 r = -EPERM;
1752 if (!kvm_arm_vcpu_is_finalized(vcpu))
1753 break;
1754
1755 r = -EFAULT;
1756 if (copy_from_user(®_list, user_list, sizeof(reg_list)))
1757 break;
1758 n = reg_list.n;
1759 reg_list.n = kvm_arm_num_regs(vcpu);
1760 if (copy_to_user(user_list, ®_list, sizeof(reg_list)))
1761 break;
1762 r = -E2BIG;
1763 if (n < reg_list.n)
1764 break;
1765 r = kvm_arm_copy_reg_indices(vcpu, user_list->reg);
1766 break;
1767 }
1768 case KVM_SET_DEVICE_ATTR: {
1769 r = -EFAULT;
1770 if (copy_from_user(&attr, argp, sizeof(attr)))
1771 break;
1772 r = kvm_arm_vcpu_set_attr(vcpu, &attr);
1773 break;
1774 }
1775 case KVM_GET_DEVICE_ATTR: {
1776 r = -EFAULT;
1777 if (copy_from_user(&attr, argp, sizeof(attr)))
1778 break;
1779 r = kvm_arm_vcpu_get_attr(vcpu, &attr);
1780 break;
1781 }
1782 case KVM_HAS_DEVICE_ATTR: {
1783 r = -EFAULT;
1784 if (copy_from_user(&attr, argp, sizeof(attr)))
1785 break;
1786 r = kvm_arm_vcpu_has_attr(vcpu, &attr);
1787 break;
1788 }
1789 case KVM_GET_VCPU_EVENTS: {
1790 struct kvm_vcpu_events events;
1791
1792 if (kvm_arm_vcpu_get_events(vcpu, &events))
1793 return -EINVAL;
1794
1795 if (copy_to_user(argp, &events, sizeof(events)))
1796 return -EFAULT;
1797
1798 return 0;
1799 }
1800 case KVM_SET_VCPU_EVENTS: {
1801 struct kvm_vcpu_events events;
1802
1803 if (copy_from_user(&events, argp, sizeof(events)))
1804 return -EFAULT;
1805
1806 return kvm_arm_vcpu_set_events(vcpu, &events);
1807 }
1808 case KVM_ARM_VCPU_FINALIZE: {
1809 int what;
1810
1811 if (!kvm_vcpu_initialized(vcpu))
1812 return -ENOEXEC;
1813
1814 if (get_user(what, (const int __user *)argp))
1815 return -EFAULT;
1816
1817 return kvm_arm_vcpu_finalize(vcpu, what);
1818 }
1819 default:
1820 r = -EINVAL;
1821 }
1822
1823 return r;
1824 }
1825
kvm_arch_sync_dirty_log(struct kvm * kvm,struct kvm_memory_slot * memslot)1826 void kvm_arch_sync_dirty_log(struct kvm *kvm, struct kvm_memory_slot *memslot)
1827 {
1828
1829 }
1830
kvm_vm_ioctl_set_device_addr(struct kvm * kvm,struct kvm_arm_device_addr * dev_addr)1831 static int kvm_vm_ioctl_set_device_addr(struct kvm *kvm,
1832 struct kvm_arm_device_addr *dev_addr)
1833 {
1834 switch (FIELD_GET(KVM_ARM_DEVICE_ID_MASK, dev_addr->id)) {
1835 case KVM_ARM_DEVICE_VGIC_V2:
1836 if (!vgic_present)
1837 return -ENXIO;
1838 return kvm_set_legacy_vgic_v2_addr(kvm, dev_addr);
1839 default:
1840 return -ENODEV;
1841 }
1842 }
1843
kvm_vm_has_attr(struct kvm * kvm,struct kvm_device_attr * attr)1844 static int kvm_vm_has_attr(struct kvm *kvm, struct kvm_device_attr *attr)
1845 {
1846 switch (attr->group) {
1847 case KVM_ARM_VM_SMCCC_CTRL:
1848 return kvm_vm_smccc_has_attr(kvm, attr);
1849 default:
1850 return -ENXIO;
1851 }
1852 }
1853
kvm_vm_set_attr(struct kvm * kvm,struct kvm_device_attr * attr)1854 static int kvm_vm_set_attr(struct kvm *kvm, struct kvm_device_attr *attr)
1855 {
1856 switch (attr->group) {
1857 case KVM_ARM_VM_SMCCC_CTRL:
1858 return kvm_vm_smccc_set_attr(kvm, attr);
1859 default:
1860 return -ENXIO;
1861 }
1862 }
1863
kvm_arch_vm_ioctl(struct file * filp,unsigned int ioctl,unsigned long arg)1864 int kvm_arch_vm_ioctl(struct file *filp, unsigned int ioctl, unsigned long arg)
1865 {
1866 struct kvm *kvm = filp->private_data;
1867 void __user *argp = (void __user *)arg;
1868 struct kvm_device_attr attr;
1869
1870 switch (ioctl) {
1871 case KVM_CREATE_IRQCHIP: {
1872 int ret;
1873 if (!vgic_present)
1874 return -ENXIO;
1875 mutex_lock(&kvm->lock);
1876 ret = kvm_vgic_create(kvm, KVM_DEV_TYPE_ARM_VGIC_V2);
1877 mutex_unlock(&kvm->lock);
1878 return ret;
1879 }
1880 case KVM_ARM_SET_DEVICE_ADDR: {
1881 struct kvm_arm_device_addr dev_addr;
1882
1883 if (copy_from_user(&dev_addr, argp, sizeof(dev_addr)))
1884 return -EFAULT;
1885 return kvm_vm_ioctl_set_device_addr(kvm, &dev_addr);
1886 }
1887 case KVM_ARM_PREFERRED_TARGET: {
1888 struct kvm_vcpu_init init = {
1889 .target = KVM_ARM_TARGET_GENERIC_V8,
1890 };
1891
1892 if (copy_to_user(argp, &init, sizeof(init)))
1893 return -EFAULT;
1894
1895 return 0;
1896 }
1897 case KVM_ARM_MTE_COPY_TAGS: {
1898 struct kvm_arm_copy_mte_tags copy_tags;
1899
1900 if (copy_from_user(©_tags, argp, sizeof(copy_tags)))
1901 return -EFAULT;
1902 return kvm_vm_ioctl_mte_copy_tags(kvm, ©_tags);
1903 }
1904 case KVM_ARM_SET_COUNTER_OFFSET: {
1905 struct kvm_arm_counter_offset offset;
1906
1907 if (copy_from_user(&offset, argp, sizeof(offset)))
1908 return -EFAULT;
1909 return kvm_vm_ioctl_set_counter_offset(kvm, &offset);
1910 }
1911 case KVM_HAS_DEVICE_ATTR: {
1912 if (copy_from_user(&attr, argp, sizeof(attr)))
1913 return -EFAULT;
1914
1915 return kvm_vm_has_attr(kvm, &attr);
1916 }
1917 case KVM_SET_DEVICE_ATTR: {
1918 if (copy_from_user(&attr, argp, sizeof(attr)))
1919 return -EFAULT;
1920
1921 return kvm_vm_set_attr(kvm, &attr);
1922 }
1923 case KVM_ARM_GET_REG_WRITABLE_MASKS: {
1924 struct reg_mask_range range;
1925
1926 if (copy_from_user(&range, argp, sizeof(range)))
1927 return -EFAULT;
1928 return kvm_vm_ioctl_get_reg_writable_masks(kvm, &range);
1929 }
1930 default:
1931 return -EINVAL;
1932 }
1933 }
1934
nvhe_percpu_size(void)1935 static unsigned long nvhe_percpu_size(void)
1936 {
1937 return (unsigned long)CHOOSE_NVHE_SYM(__per_cpu_end) -
1938 (unsigned long)CHOOSE_NVHE_SYM(__per_cpu_start);
1939 }
1940
nvhe_percpu_order(void)1941 static unsigned long nvhe_percpu_order(void)
1942 {
1943 unsigned long size = nvhe_percpu_size();
1944
1945 return size ? get_order(size) : 0;
1946 }
1947
pkvm_host_sve_state_order(void)1948 static size_t pkvm_host_sve_state_order(void)
1949 {
1950 return get_order(pkvm_host_sve_state_size());
1951 }
1952
1953 /* A lookup table holding the hypervisor VA for each vector slot */
1954 static void *hyp_spectre_vector_selector[BP_HARDEN_EL2_SLOTS];
1955
kvm_init_vector_slot(void * base,enum arm64_hyp_spectre_vector slot)1956 static void kvm_init_vector_slot(void *base, enum arm64_hyp_spectre_vector slot)
1957 {
1958 hyp_spectre_vector_selector[slot] = __kvm_vector_slot2addr(base, slot);
1959 }
1960
kvm_init_vector_slots(void)1961 static int kvm_init_vector_slots(void)
1962 {
1963 int err;
1964 void *base;
1965
1966 base = kern_hyp_va(kvm_ksym_ref(__kvm_hyp_vector));
1967 kvm_init_vector_slot(base, HYP_VECTOR_DIRECT);
1968
1969 base = kern_hyp_va(kvm_ksym_ref(__bp_harden_hyp_vecs));
1970 kvm_init_vector_slot(base, HYP_VECTOR_SPECTRE_DIRECT);
1971
1972 if (kvm_system_needs_idmapped_vectors() &&
1973 !is_protected_kvm_enabled()) {
1974 err = create_hyp_exec_mappings(__pa_symbol(__bp_harden_hyp_vecs),
1975 __BP_HARDEN_HYP_VECS_SZ, &base);
1976 if (err)
1977 return err;
1978 }
1979
1980 kvm_init_vector_slot(base, HYP_VECTOR_INDIRECT);
1981 kvm_init_vector_slot(base, HYP_VECTOR_SPECTRE_INDIRECT);
1982 return 0;
1983 }
1984
cpu_prepare_hyp_mode(int cpu,u32 hyp_va_bits)1985 static void __init cpu_prepare_hyp_mode(int cpu, u32 hyp_va_bits)
1986 {
1987 struct kvm_nvhe_init_params *params = per_cpu_ptr_nvhe_sym(kvm_init_params, cpu);
1988 unsigned long tcr;
1989
1990 /*
1991 * Calculate the raw per-cpu offset without a translation from the
1992 * kernel's mapping to the linear mapping, and store it in tpidr_el2
1993 * so that we can use adr_l to access per-cpu variables in EL2.
1994 * Also drop the KASAN tag which gets in the way...
1995 */
1996 params->tpidr_el2 = (unsigned long)kasan_reset_tag(per_cpu_ptr_nvhe_sym(__per_cpu_start, cpu)) -
1997 (unsigned long)kvm_ksym_ref(CHOOSE_NVHE_SYM(__per_cpu_start));
1998
1999 params->mair_el2 = read_sysreg(mair_el1);
2000
2001 tcr = read_sysreg(tcr_el1);
2002 if (cpus_have_final_cap(ARM64_KVM_HVHE)) {
2003 tcr &= ~(TCR_HD | TCR_HA | TCR_A1 | TCR_T0SZ_MASK);
2004 tcr |= TCR_EPD1_MASK;
2005 } else {
2006 unsigned long ips = FIELD_GET(TCR_IPS_MASK, tcr);
2007
2008 tcr &= TCR_EL2_MASK;
2009 tcr |= TCR_EL2_RES1 | FIELD_PREP(TCR_EL2_PS_MASK, ips);
2010 if (lpa2_is_enabled())
2011 tcr |= TCR_EL2_DS;
2012 }
2013 tcr |= TCR_T0SZ(hyp_va_bits);
2014 params->tcr_el2 = tcr;
2015
2016 params->pgd_pa = kvm_mmu_get_httbr();
2017 if (is_protected_kvm_enabled())
2018 params->hcr_el2 = HCR_HOST_NVHE_PROTECTED_FLAGS;
2019 else
2020 params->hcr_el2 = HCR_HOST_NVHE_FLAGS;
2021 if (cpus_have_final_cap(ARM64_KVM_HVHE))
2022 params->hcr_el2 |= HCR_E2H;
2023 params->vttbr = params->vtcr = 0;
2024
2025 /*
2026 * Flush the init params from the data cache because the struct will
2027 * be read while the MMU is off.
2028 */
2029 kvm_flush_dcache_to_poc(params, sizeof(*params));
2030 }
2031
hyp_install_host_vector(void)2032 static void hyp_install_host_vector(void)
2033 {
2034 struct kvm_nvhe_init_params *params;
2035 struct arm_smccc_res res;
2036
2037 /* Switch from the HYP stub to our own HYP init vector */
2038 __hyp_set_vectors(kvm_get_idmap_vector());
2039
2040 /*
2041 * Call initialization code, and switch to the full blown HYP code.
2042 * If the cpucaps haven't been finalized yet, something has gone very
2043 * wrong, and hyp will crash and burn when it uses any
2044 * cpus_have_*_cap() wrapper.
2045 */
2046 BUG_ON(!system_capabilities_finalized());
2047 params = this_cpu_ptr_nvhe_sym(kvm_init_params);
2048 arm_smccc_1_1_hvc(KVM_HOST_SMCCC_FUNC(__kvm_hyp_init), virt_to_phys(params), &res);
2049 WARN_ON(res.a0 != SMCCC_RET_SUCCESS);
2050 }
2051
cpu_init_hyp_mode(void)2052 static void cpu_init_hyp_mode(void)
2053 {
2054 hyp_install_host_vector();
2055
2056 /*
2057 * Disabling SSBD on a non-VHE system requires us to enable SSBS
2058 * at EL2.
2059 */
2060 if (this_cpu_has_cap(ARM64_SSBS) &&
2061 arm64_get_spectre_v4_state() == SPECTRE_VULNERABLE) {
2062 kvm_call_hyp_nvhe(__kvm_enable_ssbs);
2063 }
2064 }
2065
cpu_hyp_reset(void)2066 static void cpu_hyp_reset(void)
2067 {
2068 if (!is_kernel_in_hyp_mode())
2069 __hyp_reset_vectors();
2070 }
2071
2072 /*
2073 * EL2 vectors can be mapped and rerouted in a number of ways,
2074 * depending on the kernel configuration and CPU present:
2075 *
2076 * - If the CPU is affected by Spectre-v2, the hardening sequence is
2077 * placed in one of the vector slots, which is executed before jumping
2078 * to the real vectors.
2079 *
2080 * - If the CPU also has the ARM64_SPECTRE_V3A cap, the slot
2081 * containing the hardening sequence is mapped next to the idmap page,
2082 * and executed before jumping to the real vectors.
2083 *
2084 * - If the CPU only has the ARM64_SPECTRE_V3A cap, then an
2085 * empty slot is selected, mapped next to the idmap page, and
2086 * executed before jumping to the real vectors.
2087 *
2088 * Note that ARM64_SPECTRE_V3A is somewhat incompatible with
2089 * VHE, as we don't have hypervisor-specific mappings. If the system
2090 * is VHE and yet selects this capability, it will be ignored.
2091 */
cpu_set_hyp_vector(void)2092 static void cpu_set_hyp_vector(void)
2093 {
2094 struct bp_hardening_data *data = this_cpu_ptr(&bp_hardening_data);
2095 void *vector = hyp_spectre_vector_selector[data->slot];
2096
2097 if (!is_protected_kvm_enabled())
2098 *this_cpu_ptr_hyp_sym(kvm_hyp_vector) = (unsigned long)vector;
2099 else
2100 kvm_call_hyp_nvhe(__pkvm_cpu_set_vector, data->slot);
2101 }
2102
cpu_hyp_init_context(void)2103 static void cpu_hyp_init_context(void)
2104 {
2105 kvm_init_host_cpu_context(host_data_ptr(host_ctxt));
2106 kvm_init_host_debug_data();
2107
2108 if (!is_kernel_in_hyp_mode())
2109 cpu_init_hyp_mode();
2110 }
2111
cpu_hyp_init_features(void)2112 static void cpu_hyp_init_features(void)
2113 {
2114 cpu_set_hyp_vector();
2115
2116 if (is_kernel_in_hyp_mode())
2117 kvm_timer_init_vhe();
2118
2119 if (vgic_present)
2120 kvm_vgic_init_cpu_hardware();
2121 }
2122
cpu_hyp_reinit(void)2123 static void cpu_hyp_reinit(void)
2124 {
2125 cpu_hyp_reset();
2126 cpu_hyp_init_context();
2127 cpu_hyp_init_features();
2128 }
2129
cpu_hyp_init(void * discard)2130 static void cpu_hyp_init(void *discard)
2131 {
2132 if (!__this_cpu_read(kvm_hyp_initialized)) {
2133 cpu_hyp_reinit();
2134 __this_cpu_write(kvm_hyp_initialized, 1);
2135 }
2136 }
2137
cpu_hyp_uninit(void * discard)2138 static void cpu_hyp_uninit(void *discard)
2139 {
2140 if (!is_protected_kvm_enabled() && __this_cpu_read(kvm_hyp_initialized)) {
2141 cpu_hyp_reset();
2142 __this_cpu_write(kvm_hyp_initialized, 0);
2143 }
2144 }
2145
kvm_arch_enable_virtualization_cpu(void)2146 int kvm_arch_enable_virtualization_cpu(void)
2147 {
2148 /*
2149 * Most calls to this function are made with migration
2150 * disabled, but not with preemption disabled. The former is
2151 * enough to ensure correctness, but most of the helpers
2152 * expect the later and will throw a tantrum otherwise.
2153 */
2154 preempt_disable();
2155
2156 cpu_hyp_init(NULL);
2157
2158 kvm_vgic_cpu_up();
2159 kvm_timer_cpu_up();
2160
2161 preempt_enable();
2162
2163 return 0;
2164 }
2165
kvm_arch_disable_virtualization_cpu(void)2166 void kvm_arch_disable_virtualization_cpu(void)
2167 {
2168 kvm_timer_cpu_down();
2169 kvm_vgic_cpu_down();
2170
2171 if (!is_protected_kvm_enabled())
2172 cpu_hyp_uninit(NULL);
2173 }
2174
2175 #ifdef CONFIG_CPU_PM
hyp_init_cpu_pm_notifier(struct notifier_block * self,unsigned long cmd,void * v)2176 static int hyp_init_cpu_pm_notifier(struct notifier_block *self,
2177 unsigned long cmd,
2178 void *v)
2179 {
2180 /*
2181 * kvm_hyp_initialized is left with its old value over
2182 * PM_ENTER->PM_EXIT. It is used to indicate PM_EXIT should
2183 * re-enable hyp.
2184 */
2185 switch (cmd) {
2186 case CPU_PM_ENTER:
2187 if (__this_cpu_read(kvm_hyp_initialized))
2188 /*
2189 * don't update kvm_hyp_initialized here
2190 * so that the hyp will be re-enabled
2191 * when we resume. See below.
2192 */
2193 cpu_hyp_reset();
2194
2195 return NOTIFY_OK;
2196 case CPU_PM_ENTER_FAILED:
2197 case CPU_PM_EXIT:
2198 if (__this_cpu_read(kvm_hyp_initialized))
2199 /* The hyp was enabled before suspend. */
2200 cpu_hyp_reinit();
2201
2202 return NOTIFY_OK;
2203
2204 default:
2205 return NOTIFY_DONE;
2206 }
2207 }
2208
2209 static struct notifier_block hyp_init_cpu_pm_nb = {
2210 .notifier_call = hyp_init_cpu_pm_notifier,
2211 };
2212
hyp_cpu_pm_init(void)2213 static void __init hyp_cpu_pm_init(void)
2214 {
2215 if (!is_protected_kvm_enabled())
2216 cpu_pm_register_notifier(&hyp_init_cpu_pm_nb);
2217 }
hyp_cpu_pm_exit(void)2218 static void __init hyp_cpu_pm_exit(void)
2219 {
2220 if (!is_protected_kvm_enabled())
2221 cpu_pm_unregister_notifier(&hyp_init_cpu_pm_nb);
2222 }
2223 #else
hyp_cpu_pm_init(void)2224 static inline void __init hyp_cpu_pm_init(void)
2225 {
2226 }
hyp_cpu_pm_exit(void)2227 static inline void __init hyp_cpu_pm_exit(void)
2228 {
2229 }
2230 #endif
2231
init_cpu_logical_map(void)2232 static void __init init_cpu_logical_map(void)
2233 {
2234 unsigned int cpu;
2235
2236 /*
2237 * Copy the MPIDR <-> logical CPU ID mapping to hyp.
2238 * Only copy the set of online CPUs whose features have been checked
2239 * against the finalized system capabilities. The hypervisor will not
2240 * allow any other CPUs from the `possible` set to boot.
2241 */
2242 for_each_online_cpu(cpu)
2243 hyp_cpu_logical_map[cpu] = cpu_logical_map(cpu);
2244 }
2245
2246 #define init_psci_0_1_impl_state(config, what) \
2247 config.psci_0_1_ ## what ## _implemented = psci_ops.what
2248
init_psci_relay(void)2249 static bool __init init_psci_relay(void)
2250 {
2251 /*
2252 * If PSCI has not been initialized, protected KVM cannot install
2253 * itself on newly booted CPUs.
2254 */
2255 if (!psci_ops.get_version) {
2256 kvm_err("Cannot initialize protected mode without PSCI\n");
2257 return false;
2258 }
2259
2260 kvm_host_psci_config.version = psci_ops.get_version();
2261 kvm_host_psci_config.smccc_version = arm_smccc_get_version();
2262
2263 if (kvm_host_psci_config.version == PSCI_VERSION(0, 1)) {
2264 kvm_host_psci_config.function_ids_0_1 = get_psci_0_1_function_ids();
2265 init_psci_0_1_impl_state(kvm_host_psci_config, cpu_suspend);
2266 init_psci_0_1_impl_state(kvm_host_psci_config, cpu_on);
2267 init_psci_0_1_impl_state(kvm_host_psci_config, cpu_off);
2268 init_psci_0_1_impl_state(kvm_host_psci_config, migrate);
2269 }
2270 return true;
2271 }
2272
init_subsystems(void)2273 static int __init init_subsystems(void)
2274 {
2275 int err = 0;
2276
2277 /*
2278 * Enable hardware so that subsystem initialisation can access EL2.
2279 */
2280 on_each_cpu(cpu_hyp_init, NULL, 1);
2281
2282 /*
2283 * Register CPU lower-power notifier
2284 */
2285 hyp_cpu_pm_init();
2286
2287 /*
2288 * Init HYP view of VGIC
2289 */
2290 err = kvm_vgic_hyp_init();
2291 switch (err) {
2292 case 0:
2293 vgic_present = true;
2294 break;
2295 case -ENODEV:
2296 case -ENXIO:
2297 /*
2298 * No VGIC? No pKVM for you.
2299 *
2300 * Protected mode assumes that VGICv3 is present, so no point
2301 * in trying to hobble along if vgic initialization fails.
2302 */
2303 if (is_protected_kvm_enabled())
2304 goto out;
2305
2306 /*
2307 * Otherwise, userspace could choose to implement a GIC for its
2308 * guest on non-cooperative hardware.
2309 */
2310 vgic_present = false;
2311 err = 0;
2312 break;
2313 default:
2314 goto out;
2315 }
2316
2317 if (kvm_mode == KVM_MODE_NV &&
2318 !(vgic_present && kvm_vgic_global_state.type == VGIC_V3)) {
2319 kvm_err("NV support requires GICv3, giving up\n");
2320 err = -EINVAL;
2321 goto out;
2322 }
2323
2324 /*
2325 * Init HYP architected timer support
2326 */
2327 err = kvm_timer_hyp_init(vgic_present);
2328 if (err)
2329 goto out;
2330
2331 kvm_register_perf_callbacks(NULL);
2332
2333 out:
2334 if (err)
2335 hyp_cpu_pm_exit();
2336
2337 if (err || !is_protected_kvm_enabled())
2338 on_each_cpu(cpu_hyp_uninit, NULL, 1);
2339
2340 return err;
2341 }
2342
teardown_subsystems(void)2343 static void __init teardown_subsystems(void)
2344 {
2345 kvm_unregister_perf_callbacks();
2346 hyp_cpu_pm_exit();
2347 }
2348
teardown_hyp_mode(void)2349 static void __init teardown_hyp_mode(void)
2350 {
2351 bool free_sve = system_supports_sve() && is_protected_kvm_enabled();
2352 int cpu;
2353
2354 free_hyp_pgds();
2355 for_each_possible_cpu(cpu) {
2356 if (per_cpu(kvm_hyp_initialized, cpu))
2357 continue;
2358
2359 free_pages(per_cpu(kvm_arm_hyp_stack_base, cpu), NVHE_STACK_SHIFT - PAGE_SHIFT);
2360
2361 if (!kvm_nvhe_sym(kvm_arm_hyp_percpu_base)[cpu])
2362 continue;
2363
2364 if (free_sve) {
2365 struct cpu_sve_state *sve_state;
2366
2367 sve_state = per_cpu_ptr_nvhe_sym(kvm_host_data, cpu)->sve_state;
2368 free_pages((unsigned long) sve_state, pkvm_host_sve_state_order());
2369 }
2370
2371 free_pages(kvm_nvhe_sym(kvm_arm_hyp_percpu_base)[cpu], nvhe_percpu_order());
2372
2373 }
2374 }
2375
do_pkvm_init(u32 hyp_va_bits)2376 static int __init do_pkvm_init(u32 hyp_va_bits)
2377 {
2378 void *per_cpu_base = kvm_ksym_ref(kvm_nvhe_sym(kvm_arm_hyp_percpu_base));
2379 int ret;
2380
2381 preempt_disable();
2382 cpu_hyp_init_context();
2383 ret = kvm_call_hyp_nvhe(__pkvm_init, hyp_mem_base, hyp_mem_size,
2384 num_possible_cpus(), kern_hyp_va(per_cpu_base),
2385 hyp_va_bits);
2386 cpu_hyp_init_features();
2387
2388 /*
2389 * The stub hypercalls are now disabled, so set our local flag to
2390 * prevent a later re-init attempt in kvm_arch_enable_virtualization_cpu().
2391 */
2392 __this_cpu_write(kvm_hyp_initialized, 1);
2393 preempt_enable();
2394
2395 return ret;
2396 }
2397
get_hyp_id_aa64pfr0_el1(void)2398 static u64 get_hyp_id_aa64pfr0_el1(void)
2399 {
2400 /*
2401 * Track whether the system isn't affected by spectre/meltdown in the
2402 * hypervisor's view of id_aa64pfr0_el1, used for protected VMs.
2403 * Although this is per-CPU, we make it global for simplicity, e.g., not
2404 * to have to worry about vcpu migration.
2405 *
2406 * Unlike for non-protected VMs, userspace cannot override this for
2407 * protected VMs.
2408 */
2409 u64 val = read_sanitised_ftr_reg(SYS_ID_AA64PFR0_EL1);
2410
2411 val &= ~(ARM64_FEATURE_MASK(ID_AA64PFR0_EL1_CSV2) |
2412 ARM64_FEATURE_MASK(ID_AA64PFR0_EL1_CSV3));
2413
2414 val |= FIELD_PREP(ARM64_FEATURE_MASK(ID_AA64PFR0_EL1_CSV2),
2415 arm64_get_spectre_v2_state() == SPECTRE_UNAFFECTED);
2416 val |= FIELD_PREP(ARM64_FEATURE_MASK(ID_AA64PFR0_EL1_CSV3),
2417 arm64_get_meltdown_state() == SPECTRE_UNAFFECTED);
2418
2419 return val;
2420 }
2421
kvm_hyp_init_symbols(void)2422 static void kvm_hyp_init_symbols(void)
2423 {
2424 kvm_nvhe_sym(id_aa64pfr0_el1_sys_val) = get_hyp_id_aa64pfr0_el1();
2425 kvm_nvhe_sym(id_aa64pfr1_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64PFR1_EL1);
2426 kvm_nvhe_sym(id_aa64isar0_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64ISAR0_EL1);
2427 kvm_nvhe_sym(id_aa64isar1_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64ISAR1_EL1);
2428 kvm_nvhe_sym(id_aa64isar2_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64ISAR2_EL1);
2429 kvm_nvhe_sym(id_aa64mmfr0_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64MMFR0_EL1);
2430 kvm_nvhe_sym(id_aa64mmfr1_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64MMFR1_EL1);
2431 kvm_nvhe_sym(id_aa64mmfr2_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64MMFR2_EL1);
2432 kvm_nvhe_sym(id_aa64smfr0_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64SMFR0_EL1);
2433 kvm_nvhe_sym(__icache_flags) = __icache_flags;
2434 kvm_nvhe_sym(kvm_arm_vmid_bits) = kvm_arm_vmid_bits;
2435
2436 /* Propagate the FGT state to the the nVHE side */
2437 kvm_nvhe_sym(hfgrtr_masks) = hfgrtr_masks;
2438 kvm_nvhe_sym(hfgwtr_masks) = hfgwtr_masks;
2439 kvm_nvhe_sym(hfgitr_masks) = hfgitr_masks;
2440 kvm_nvhe_sym(hdfgrtr_masks) = hdfgrtr_masks;
2441 kvm_nvhe_sym(hdfgwtr_masks) = hdfgwtr_masks;
2442 kvm_nvhe_sym(hafgrtr_masks) = hafgrtr_masks;
2443 kvm_nvhe_sym(hfgrtr2_masks) = hfgrtr2_masks;
2444 kvm_nvhe_sym(hfgwtr2_masks) = hfgwtr2_masks;
2445 kvm_nvhe_sym(hfgitr2_masks) = hfgitr2_masks;
2446 kvm_nvhe_sym(hdfgrtr2_masks)= hdfgrtr2_masks;
2447 kvm_nvhe_sym(hdfgwtr2_masks)= hdfgwtr2_masks;
2448
2449 /*
2450 * Flush entire BSS since part of its data containing init symbols is read
2451 * while the MMU is off.
2452 */
2453 kvm_flush_dcache_to_poc(kvm_ksym_ref(__hyp_bss_start),
2454 kvm_ksym_ref(__hyp_bss_end) - kvm_ksym_ref(__hyp_bss_start));
2455 }
2456
kvm_hyp_init_protection(u32 hyp_va_bits)2457 static int __init kvm_hyp_init_protection(u32 hyp_va_bits)
2458 {
2459 void *addr = phys_to_virt(hyp_mem_base);
2460 int ret;
2461
2462 ret = create_hyp_mappings(addr, addr + hyp_mem_size, PAGE_HYP);
2463 if (ret)
2464 return ret;
2465
2466 ret = do_pkvm_init(hyp_va_bits);
2467 if (ret)
2468 return ret;
2469
2470 free_hyp_pgds();
2471
2472 return 0;
2473 }
2474
init_pkvm_host_sve_state(void)2475 static int init_pkvm_host_sve_state(void)
2476 {
2477 int cpu;
2478
2479 if (!system_supports_sve())
2480 return 0;
2481
2482 /* Allocate pages for host sve state in protected mode. */
2483 for_each_possible_cpu(cpu) {
2484 struct page *page = alloc_pages(GFP_KERNEL, pkvm_host_sve_state_order());
2485
2486 if (!page)
2487 return -ENOMEM;
2488
2489 per_cpu_ptr_nvhe_sym(kvm_host_data, cpu)->sve_state = page_address(page);
2490 }
2491
2492 /*
2493 * Don't map the pages in hyp since these are only used in protected
2494 * mode, which will (re)create its own mapping when initialized.
2495 */
2496
2497 return 0;
2498 }
2499
2500 /*
2501 * Finalizes the initialization of hyp mode, once everything else is initialized
2502 * and the initialziation process cannot fail.
2503 */
finalize_init_hyp_mode(void)2504 static void finalize_init_hyp_mode(void)
2505 {
2506 int cpu;
2507
2508 if (system_supports_sve() && is_protected_kvm_enabled()) {
2509 for_each_possible_cpu(cpu) {
2510 struct cpu_sve_state *sve_state;
2511
2512 sve_state = per_cpu_ptr_nvhe_sym(kvm_host_data, cpu)->sve_state;
2513 per_cpu_ptr_nvhe_sym(kvm_host_data, cpu)->sve_state =
2514 kern_hyp_va(sve_state);
2515 }
2516 }
2517 }
2518
pkvm_hyp_init_ptrauth(void)2519 static void pkvm_hyp_init_ptrauth(void)
2520 {
2521 struct kvm_cpu_context *hyp_ctxt;
2522 int cpu;
2523
2524 for_each_possible_cpu(cpu) {
2525 hyp_ctxt = per_cpu_ptr_nvhe_sym(kvm_hyp_ctxt, cpu);
2526 hyp_ctxt->sys_regs[APIAKEYLO_EL1] = get_random_long();
2527 hyp_ctxt->sys_regs[APIAKEYHI_EL1] = get_random_long();
2528 hyp_ctxt->sys_regs[APIBKEYLO_EL1] = get_random_long();
2529 hyp_ctxt->sys_regs[APIBKEYHI_EL1] = get_random_long();
2530 hyp_ctxt->sys_regs[APDAKEYLO_EL1] = get_random_long();
2531 hyp_ctxt->sys_regs[APDAKEYHI_EL1] = get_random_long();
2532 hyp_ctxt->sys_regs[APDBKEYLO_EL1] = get_random_long();
2533 hyp_ctxt->sys_regs[APDBKEYHI_EL1] = get_random_long();
2534 hyp_ctxt->sys_regs[APGAKEYLO_EL1] = get_random_long();
2535 hyp_ctxt->sys_regs[APGAKEYHI_EL1] = get_random_long();
2536 }
2537 }
2538
2539 /* Inits Hyp-mode on all online CPUs */
init_hyp_mode(void)2540 static int __init init_hyp_mode(void)
2541 {
2542 u32 hyp_va_bits;
2543 int cpu;
2544 int err = -ENOMEM;
2545
2546 /*
2547 * The protected Hyp-mode cannot be initialized if the memory pool
2548 * allocation has failed.
2549 */
2550 if (is_protected_kvm_enabled() && !hyp_mem_base)
2551 goto out_err;
2552
2553 /*
2554 * Allocate Hyp PGD and setup Hyp identity mapping
2555 */
2556 err = kvm_mmu_init(&hyp_va_bits);
2557 if (err)
2558 goto out_err;
2559
2560 /*
2561 * Allocate stack pages for Hypervisor-mode
2562 */
2563 for_each_possible_cpu(cpu) {
2564 unsigned long stack_base;
2565
2566 stack_base = __get_free_pages(GFP_KERNEL, NVHE_STACK_SHIFT - PAGE_SHIFT);
2567 if (!stack_base) {
2568 err = -ENOMEM;
2569 goto out_err;
2570 }
2571
2572 per_cpu(kvm_arm_hyp_stack_base, cpu) = stack_base;
2573 }
2574
2575 /*
2576 * Allocate and initialize pages for Hypervisor-mode percpu regions.
2577 */
2578 for_each_possible_cpu(cpu) {
2579 struct page *page;
2580 void *page_addr;
2581
2582 page = alloc_pages(GFP_KERNEL, nvhe_percpu_order());
2583 if (!page) {
2584 err = -ENOMEM;
2585 goto out_err;
2586 }
2587
2588 page_addr = page_address(page);
2589 memcpy(page_addr, CHOOSE_NVHE_SYM(__per_cpu_start), nvhe_percpu_size());
2590 kvm_nvhe_sym(kvm_arm_hyp_percpu_base)[cpu] = (unsigned long)page_addr;
2591 }
2592
2593 /*
2594 * Map the Hyp-code called directly from the host
2595 */
2596 err = create_hyp_mappings(kvm_ksym_ref(__hyp_text_start),
2597 kvm_ksym_ref(__hyp_text_end), PAGE_HYP_EXEC);
2598 if (err) {
2599 kvm_err("Cannot map world-switch code\n");
2600 goto out_err;
2601 }
2602
2603 err = create_hyp_mappings(kvm_ksym_ref(__hyp_data_start),
2604 kvm_ksym_ref(__hyp_data_end), PAGE_HYP);
2605 if (err) {
2606 kvm_err("Cannot map .hyp.data section\n");
2607 goto out_err;
2608 }
2609
2610 err = create_hyp_mappings(kvm_ksym_ref(__hyp_rodata_start),
2611 kvm_ksym_ref(__hyp_rodata_end), PAGE_HYP_RO);
2612 if (err) {
2613 kvm_err("Cannot map .hyp.rodata section\n");
2614 goto out_err;
2615 }
2616
2617 err = create_hyp_mappings(kvm_ksym_ref(__start_rodata),
2618 kvm_ksym_ref(__end_rodata), PAGE_HYP_RO);
2619 if (err) {
2620 kvm_err("Cannot map rodata section\n");
2621 goto out_err;
2622 }
2623
2624 /*
2625 * .hyp.bss is guaranteed to be placed at the beginning of the .bss
2626 * section thanks to an assertion in the linker script. Map it RW and
2627 * the rest of .bss RO.
2628 */
2629 err = create_hyp_mappings(kvm_ksym_ref(__hyp_bss_start),
2630 kvm_ksym_ref(__hyp_bss_end), PAGE_HYP);
2631 if (err) {
2632 kvm_err("Cannot map hyp bss section: %d\n", err);
2633 goto out_err;
2634 }
2635
2636 err = create_hyp_mappings(kvm_ksym_ref(__hyp_bss_end),
2637 kvm_ksym_ref(__bss_stop), PAGE_HYP_RO);
2638 if (err) {
2639 kvm_err("Cannot map bss section\n");
2640 goto out_err;
2641 }
2642
2643 /*
2644 * Map the Hyp stack pages
2645 */
2646 for_each_possible_cpu(cpu) {
2647 struct kvm_nvhe_init_params *params = per_cpu_ptr_nvhe_sym(kvm_init_params, cpu);
2648 char *stack_base = (char *)per_cpu(kvm_arm_hyp_stack_base, cpu);
2649
2650 err = create_hyp_stack(__pa(stack_base), ¶ms->stack_hyp_va);
2651 if (err) {
2652 kvm_err("Cannot map hyp stack\n");
2653 goto out_err;
2654 }
2655
2656 /*
2657 * Save the stack PA in nvhe_init_params. This will be needed
2658 * to recreate the stack mapping in protected nVHE mode.
2659 * __hyp_pa() won't do the right thing there, since the stack
2660 * has been mapped in the flexible private VA space.
2661 */
2662 params->stack_pa = __pa(stack_base);
2663 }
2664
2665 for_each_possible_cpu(cpu) {
2666 char *percpu_begin = (char *)kvm_nvhe_sym(kvm_arm_hyp_percpu_base)[cpu];
2667 char *percpu_end = percpu_begin + nvhe_percpu_size();
2668
2669 /* Map Hyp percpu pages */
2670 err = create_hyp_mappings(percpu_begin, percpu_end, PAGE_HYP);
2671 if (err) {
2672 kvm_err("Cannot map hyp percpu region\n");
2673 goto out_err;
2674 }
2675
2676 /* Prepare the CPU initialization parameters */
2677 cpu_prepare_hyp_mode(cpu, hyp_va_bits);
2678 }
2679
2680 kvm_hyp_init_symbols();
2681
2682 if (is_protected_kvm_enabled()) {
2683 if (IS_ENABLED(CONFIG_ARM64_PTR_AUTH_KERNEL) &&
2684 cpus_have_final_cap(ARM64_HAS_ADDRESS_AUTH))
2685 pkvm_hyp_init_ptrauth();
2686
2687 init_cpu_logical_map();
2688
2689 if (!init_psci_relay()) {
2690 err = -ENODEV;
2691 goto out_err;
2692 }
2693
2694 err = init_pkvm_host_sve_state();
2695 if (err)
2696 goto out_err;
2697
2698 err = kvm_hyp_init_protection(hyp_va_bits);
2699 if (err) {
2700 kvm_err("Failed to init hyp memory protection\n");
2701 goto out_err;
2702 }
2703 }
2704
2705 return 0;
2706
2707 out_err:
2708 teardown_hyp_mode();
2709 kvm_err("error initializing Hyp mode: %d\n", err);
2710 return err;
2711 }
2712
kvm_mpidr_to_vcpu(struct kvm * kvm,unsigned long mpidr)2713 struct kvm_vcpu *kvm_mpidr_to_vcpu(struct kvm *kvm, unsigned long mpidr)
2714 {
2715 struct kvm_vcpu *vcpu = NULL;
2716 struct kvm_mpidr_data *data;
2717 unsigned long i;
2718
2719 mpidr &= MPIDR_HWID_BITMASK;
2720
2721 rcu_read_lock();
2722 data = rcu_dereference(kvm->arch.mpidr_data);
2723
2724 if (data) {
2725 u16 idx = kvm_mpidr_index(data, mpidr);
2726
2727 vcpu = kvm_get_vcpu(kvm, data->cmpidr_to_idx[idx]);
2728 if (mpidr != kvm_vcpu_get_mpidr_aff(vcpu))
2729 vcpu = NULL;
2730 }
2731
2732 rcu_read_unlock();
2733
2734 if (vcpu)
2735 return vcpu;
2736
2737 kvm_for_each_vcpu(i, vcpu, kvm) {
2738 if (mpidr == kvm_vcpu_get_mpidr_aff(vcpu))
2739 return vcpu;
2740 }
2741 return NULL;
2742 }
2743
kvm_arch_irqchip_in_kernel(struct kvm * kvm)2744 bool kvm_arch_irqchip_in_kernel(struct kvm *kvm)
2745 {
2746 return irqchip_in_kernel(kvm);
2747 }
2748
kvm_arch_irq_bypass_add_producer(struct irq_bypass_consumer * cons,struct irq_bypass_producer * prod)2749 int kvm_arch_irq_bypass_add_producer(struct irq_bypass_consumer *cons,
2750 struct irq_bypass_producer *prod)
2751 {
2752 struct kvm_kernel_irqfd *irqfd =
2753 container_of(cons, struct kvm_kernel_irqfd, consumer);
2754 struct kvm_kernel_irq_routing_entry *irq_entry = &irqfd->irq_entry;
2755
2756 /*
2757 * The only thing we have a chance of directly-injecting is LPIs. Maybe
2758 * one day...
2759 */
2760 if (irq_entry->type != KVM_IRQ_ROUTING_MSI)
2761 return 0;
2762
2763 return kvm_vgic_v4_set_forwarding(irqfd->kvm, prod->irq,
2764 &irqfd->irq_entry);
2765 }
2766
kvm_arch_irq_bypass_del_producer(struct irq_bypass_consumer * cons,struct irq_bypass_producer * prod)2767 void kvm_arch_irq_bypass_del_producer(struct irq_bypass_consumer *cons,
2768 struct irq_bypass_producer *prod)
2769 {
2770 struct kvm_kernel_irqfd *irqfd =
2771 container_of(cons, struct kvm_kernel_irqfd, consumer);
2772 struct kvm_kernel_irq_routing_entry *irq_entry = &irqfd->irq_entry;
2773
2774 if (irq_entry->type != KVM_IRQ_ROUTING_MSI)
2775 return;
2776
2777 kvm_vgic_v4_unset_forwarding(irqfd->kvm, prod->irq);
2778 }
2779
kvm_arch_update_irqfd_routing(struct kvm_kernel_irqfd * irqfd,struct kvm_kernel_irq_routing_entry * old,struct kvm_kernel_irq_routing_entry * new)2780 void kvm_arch_update_irqfd_routing(struct kvm_kernel_irqfd *irqfd,
2781 struct kvm_kernel_irq_routing_entry *old,
2782 struct kvm_kernel_irq_routing_entry *new)
2783 {
2784 if (old->type == KVM_IRQ_ROUTING_MSI &&
2785 new->type == KVM_IRQ_ROUTING_MSI &&
2786 !memcmp(&old->msi, &new->msi, sizeof(new->msi)))
2787 return;
2788
2789 /*
2790 * Remapping the vLPI requires taking the its_lock mutex to resolve
2791 * the new translation. We're in spinlock land at this point, so no
2792 * chance of resolving the translation.
2793 *
2794 * Unmap the vLPI and fall back to software LPI injection.
2795 */
2796 return kvm_vgic_v4_unset_forwarding(irqfd->kvm, irqfd->producer->irq);
2797 }
2798
kvm_arch_irq_bypass_stop(struct irq_bypass_consumer * cons)2799 void kvm_arch_irq_bypass_stop(struct irq_bypass_consumer *cons)
2800 {
2801 struct kvm_kernel_irqfd *irqfd =
2802 container_of(cons, struct kvm_kernel_irqfd, consumer);
2803
2804 kvm_arm_halt_guest(irqfd->kvm);
2805 }
2806
kvm_arch_irq_bypass_start(struct irq_bypass_consumer * cons)2807 void kvm_arch_irq_bypass_start(struct irq_bypass_consumer *cons)
2808 {
2809 struct kvm_kernel_irqfd *irqfd =
2810 container_of(cons, struct kvm_kernel_irqfd, consumer);
2811
2812 kvm_arm_resume_guest(irqfd->kvm);
2813 }
2814
2815 /* Initialize Hyp-mode and memory mappings on all CPUs */
kvm_arm_init(void)2816 static __init int kvm_arm_init(void)
2817 {
2818 int err;
2819 bool in_hyp_mode;
2820
2821 if (!is_hyp_mode_available()) {
2822 kvm_info("HYP mode not available\n");
2823 return -ENODEV;
2824 }
2825
2826 if (kvm_get_mode() == KVM_MODE_NONE) {
2827 kvm_info("KVM disabled from command line\n");
2828 return -ENODEV;
2829 }
2830
2831 err = kvm_sys_reg_table_init();
2832 if (err) {
2833 kvm_info("Error initializing system register tables");
2834 return err;
2835 }
2836
2837 in_hyp_mode = is_kernel_in_hyp_mode();
2838
2839 if (cpus_have_final_cap(ARM64_WORKAROUND_DEVICE_LOAD_ACQUIRE) ||
2840 cpus_have_final_cap(ARM64_WORKAROUND_1508412))
2841 kvm_info("Guests without required CPU erratum workarounds can deadlock system!\n" \
2842 "Only trusted guests should be used on this system.\n");
2843
2844 err = kvm_set_ipa_limit();
2845 if (err)
2846 return err;
2847
2848 err = kvm_arm_init_sve();
2849 if (err)
2850 return err;
2851
2852 err = kvm_arm_vmid_alloc_init();
2853 if (err) {
2854 kvm_err("Failed to initialize VMID allocator.\n");
2855 return err;
2856 }
2857
2858 if (!in_hyp_mode) {
2859 err = init_hyp_mode();
2860 if (err)
2861 goto out_err;
2862 }
2863
2864 err = kvm_init_vector_slots();
2865 if (err) {
2866 kvm_err("Cannot initialise vector slots\n");
2867 goto out_hyp;
2868 }
2869
2870 err = init_subsystems();
2871 if (err)
2872 goto out_hyp;
2873
2874 kvm_info("%s%sVHE%s mode initialized successfully\n",
2875 in_hyp_mode ? "" : (is_protected_kvm_enabled() ?
2876 "Protected " : "Hyp "),
2877 in_hyp_mode ? "" : (cpus_have_final_cap(ARM64_KVM_HVHE) ?
2878 "h" : "n"),
2879 cpus_have_final_cap(ARM64_HAS_NESTED_VIRT) ? "+NV2": "");
2880
2881 /*
2882 * FIXME: Do something reasonable if kvm_init() fails after pKVM
2883 * hypervisor protection is finalized.
2884 */
2885 err = kvm_init(sizeof(struct kvm_vcpu), 0, THIS_MODULE);
2886 if (err)
2887 goto out_subs;
2888
2889 /*
2890 * This should be called after initialization is done and failure isn't
2891 * possible anymore.
2892 */
2893 if (!in_hyp_mode)
2894 finalize_init_hyp_mode();
2895
2896 kvm_arm_initialised = true;
2897
2898 return 0;
2899
2900 out_subs:
2901 teardown_subsystems();
2902 out_hyp:
2903 if (!in_hyp_mode)
2904 teardown_hyp_mode();
2905 out_err:
2906 kvm_arm_vmid_alloc_free();
2907 return err;
2908 }
2909
early_kvm_mode_cfg(char * arg)2910 static int __init early_kvm_mode_cfg(char *arg)
2911 {
2912 if (!arg)
2913 return -EINVAL;
2914
2915 if (strcmp(arg, "none") == 0) {
2916 kvm_mode = KVM_MODE_NONE;
2917 return 0;
2918 }
2919
2920 if (!is_hyp_mode_available()) {
2921 pr_warn_once("KVM is not available. Ignoring kvm-arm.mode\n");
2922 return 0;
2923 }
2924
2925 if (strcmp(arg, "protected") == 0) {
2926 if (!is_kernel_in_hyp_mode())
2927 kvm_mode = KVM_MODE_PROTECTED;
2928 else
2929 pr_warn_once("Protected KVM not available with VHE\n");
2930
2931 return 0;
2932 }
2933
2934 if (strcmp(arg, "nvhe") == 0 && !WARN_ON(is_kernel_in_hyp_mode())) {
2935 kvm_mode = KVM_MODE_DEFAULT;
2936 return 0;
2937 }
2938
2939 if (strcmp(arg, "nested") == 0 && !WARN_ON(!is_kernel_in_hyp_mode())) {
2940 kvm_mode = KVM_MODE_NV;
2941 return 0;
2942 }
2943
2944 return -EINVAL;
2945 }
2946 early_param("kvm-arm.mode", early_kvm_mode_cfg);
2947
early_kvm_wfx_trap_policy_cfg(char * arg,enum kvm_wfx_trap_policy * p)2948 static int __init early_kvm_wfx_trap_policy_cfg(char *arg, enum kvm_wfx_trap_policy *p)
2949 {
2950 if (!arg)
2951 return -EINVAL;
2952
2953 if (strcmp(arg, "trap") == 0) {
2954 *p = KVM_WFX_TRAP;
2955 return 0;
2956 }
2957
2958 if (strcmp(arg, "notrap") == 0) {
2959 *p = KVM_WFX_NOTRAP;
2960 return 0;
2961 }
2962
2963 return -EINVAL;
2964 }
2965
early_kvm_wfi_trap_policy_cfg(char * arg)2966 static int __init early_kvm_wfi_trap_policy_cfg(char *arg)
2967 {
2968 return early_kvm_wfx_trap_policy_cfg(arg, &kvm_wfi_trap_policy);
2969 }
2970 early_param("kvm-arm.wfi_trap_policy", early_kvm_wfi_trap_policy_cfg);
2971
early_kvm_wfe_trap_policy_cfg(char * arg)2972 static int __init early_kvm_wfe_trap_policy_cfg(char *arg)
2973 {
2974 return early_kvm_wfx_trap_policy_cfg(arg, &kvm_wfe_trap_policy);
2975 }
2976 early_param("kvm-arm.wfe_trap_policy", early_kvm_wfe_trap_policy_cfg);
2977
kvm_get_mode(void)2978 enum kvm_mode kvm_get_mode(void)
2979 {
2980 return kvm_mode;
2981 }
2982
2983 module_init(kvm_arm_init);
2984