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 default:
412 r = 0;
413 }
414
415 return r;
416 }
417
kvm_arch_dev_ioctl(struct file * filp,unsigned int ioctl,unsigned long arg)418 long kvm_arch_dev_ioctl(struct file *filp,
419 unsigned int ioctl, unsigned long arg)
420 {
421 return -EINVAL;
422 }
423
kvm_arch_alloc_vm(void)424 struct kvm *kvm_arch_alloc_vm(void)
425 {
426 size_t sz = sizeof(struct kvm);
427
428 if (!has_vhe())
429 return kzalloc(sz, GFP_KERNEL_ACCOUNT);
430
431 return __vmalloc(sz, GFP_KERNEL_ACCOUNT | __GFP_HIGHMEM | __GFP_ZERO);
432 }
433
kvm_arch_vcpu_precreate(struct kvm * kvm,unsigned int id)434 int kvm_arch_vcpu_precreate(struct kvm *kvm, unsigned int id)
435 {
436 if (irqchip_in_kernel(kvm) && vgic_initialized(kvm))
437 return -EBUSY;
438
439 if (id >= kvm->max_vcpus)
440 return -EINVAL;
441
442 return 0;
443 }
444
kvm_arch_vcpu_create(struct kvm_vcpu * vcpu)445 int kvm_arch_vcpu_create(struct kvm_vcpu *vcpu)
446 {
447 int err;
448
449 spin_lock_init(&vcpu->arch.mp_state_lock);
450
451 #ifdef CONFIG_LOCKDEP
452 /* Inform lockdep that the config_lock is acquired after vcpu->mutex */
453 mutex_lock(&vcpu->mutex);
454 mutex_lock(&vcpu->kvm->arch.config_lock);
455 mutex_unlock(&vcpu->kvm->arch.config_lock);
456 mutex_unlock(&vcpu->mutex);
457 #endif
458
459 /* Force users to call KVM_ARM_VCPU_INIT */
460 vcpu_clear_flag(vcpu, VCPU_INITIALIZED);
461
462 vcpu->arch.mmu_page_cache.gfp_zero = __GFP_ZERO;
463
464 /* Set up the timer */
465 kvm_timer_vcpu_init(vcpu);
466
467 kvm_pmu_vcpu_init(vcpu);
468
469 kvm_arm_pvtime_vcpu_init(&vcpu->arch);
470
471 vcpu->arch.hw_mmu = &vcpu->kvm->arch.mmu;
472
473 /*
474 * This vCPU may have been created after mpidr_data was initialized.
475 * Throw out the pre-computed mappings if that is the case which forces
476 * KVM to fall back to iteratively searching the vCPUs.
477 */
478 kvm_destroy_mpidr_data(vcpu->kvm);
479
480 err = kvm_vgic_vcpu_init(vcpu);
481 if (err)
482 return err;
483
484 err = kvm_share_hyp(vcpu, vcpu + 1);
485 if (err)
486 kvm_vgic_vcpu_destroy(vcpu);
487
488 return err;
489 }
490
kvm_arch_vcpu_postcreate(struct kvm_vcpu * vcpu)491 void kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu)
492 {
493 }
494
kvm_arch_vcpu_destroy(struct kvm_vcpu * vcpu)495 void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu)
496 {
497 if (!is_protected_kvm_enabled())
498 kvm_mmu_free_memory_cache(&vcpu->arch.mmu_page_cache);
499 else
500 free_hyp_memcache(&vcpu->arch.pkvm_memcache);
501 kvm_timer_vcpu_terminate(vcpu);
502 kvm_pmu_vcpu_destroy(vcpu);
503 kvm_vgic_vcpu_destroy(vcpu);
504 kvm_arm_vcpu_destroy(vcpu);
505 }
506
kvm_arch_vcpu_blocking(struct kvm_vcpu * vcpu)507 void kvm_arch_vcpu_blocking(struct kvm_vcpu *vcpu)
508 {
509
510 }
511
kvm_arch_vcpu_unblocking(struct kvm_vcpu * vcpu)512 void kvm_arch_vcpu_unblocking(struct kvm_vcpu *vcpu)
513 {
514
515 }
516
vcpu_set_pauth_traps(struct kvm_vcpu * vcpu)517 static void vcpu_set_pauth_traps(struct kvm_vcpu *vcpu)
518 {
519 if (vcpu_has_ptrauth(vcpu) && !is_protected_kvm_enabled()) {
520 /*
521 * Either we're running an L2 guest, and the API/APK bits come
522 * from L1's HCR_EL2, or API/APK are both set.
523 */
524 if (unlikely(vcpu_has_nv(vcpu) && !is_hyp_ctxt(vcpu))) {
525 u64 val;
526
527 val = __vcpu_sys_reg(vcpu, HCR_EL2);
528 val &= (HCR_API | HCR_APK);
529 vcpu->arch.hcr_el2 &= ~(HCR_API | HCR_APK);
530 vcpu->arch.hcr_el2 |= val;
531 } else {
532 vcpu->arch.hcr_el2 |= (HCR_API | HCR_APK);
533 }
534
535 /*
536 * Save the host keys if there is any chance for the guest
537 * to use pauth, as the entry code will reload the guest
538 * keys in that case.
539 */
540 if (vcpu->arch.hcr_el2 & (HCR_API | HCR_APK)) {
541 struct kvm_cpu_context *ctxt;
542
543 ctxt = this_cpu_ptr_hyp_sym(kvm_hyp_ctxt);
544 ptrauth_save_keys(ctxt);
545 }
546 }
547 }
548
kvm_vcpu_should_clear_twi(struct kvm_vcpu * vcpu)549 static bool kvm_vcpu_should_clear_twi(struct kvm_vcpu *vcpu)
550 {
551 if (unlikely(kvm_wfi_trap_policy != KVM_WFX_NOTRAP_SINGLE_TASK))
552 return kvm_wfi_trap_policy == KVM_WFX_NOTRAP;
553
554 return single_task_running() &&
555 (atomic_read(&vcpu->arch.vgic_cpu.vgic_v3.its_vpe.vlpi_count) ||
556 vcpu->kvm->arch.vgic.nassgireq);
557 }
558
kvm_vcpu_should_clear_twe(struct kvm_vcpu * vcpu)559 static bool kvm_vcpu_should_clear_twe(struct kvm_vcpu *vcpu)
560 {
561 if (unlikely(kvm_wfe_trap_policy != KVM_WFX_NOTRAP_SINGLE_TASK))
562 return kvm_wfe_trap_policy == KVM_WFX_NOTRAP;
563
564 return single_task_running();
565 }
566
kvm_arch_vcpu_load(struct kvm_vcpu * vcpu,int cpu)567 void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
568 {
569 struct kvm_s2_mmu *mmu;
570 int *last_ran;
571
572 if (is_protected_kvm_enabled())
573 goto nommu;
574
575 if (vcpu_has_nv(vcpu))
576 kvm_vcpu_load_hw_mmu(vcpu);
577
578 mmu = vcpu->arch.hw_mmu;
579 last_ran = this_cpu_ptr(mmu->last_vcpu_ran);
580
581 /*
582 * Ensure a VMID is allocated for the MMU before programming VTTBR_EL2,
583 * which happens eagerly in VHE.
584 *
585 * Also, the VMID allocator only preserves VMIDs that are active at the
586 * time of rollover, so KVM might need to grab a new VMID for the MMU if
587 * this is called from kvm_sched_in().
588 */
589 kvm_arm_vmid_update(&mmu->vmid);
590
591 /*
592 * We guarantee that both TLBs and I-cache are private to each
593 * vcpu. If detecting that a vcpu from the same VM has
594 * previously run on the same physical CPU, call into the
595 * hypervisor code to nuke the relevant contexts.
596 *
597 * We might get preempted before the vCPU actually runs, but
598 * over-invalidation doesn't affect correctness.
599 */
600 if (*last_ran != vcpu->vcpu_idx) {
601 kvm_call_hyp(__kvm_flush_cpu_context, mmu);
602 *last_ran = vcpu->vcpu_idx;
603 }
604
605 nommu:
606 vcpu->cpu = cpu;
607
608 /*
609 * The timer must be loaded before the vgic to correctly set up physical
610 * interrupt deactivation in nested state (e.g. timer interrupt).
611 */
612 kvm_timer_vcpu_load(vcpu);
613 kvm_vgic_load(vcpu);
614 kvm_vcpu_load_debug(vcpu);
615 if (has_vhe())
616 kvm_vcpu_load_vhe(vcpu);
617 kvm_arch_vcpu_load_fp(vcpu);
618 kvm_vcpu_pmu_restore_guest(vcpu);
619 if (kvm_arm_is_pvtime_enabled(&vcpu->arch))
620 kvm_make_request(KVM_REQ_RECORD_STEAL, vcpu);
621
622 if (kvm_vcpu_should_clear_twe(vcpu))
623 vcpu->arch.hcr_el2 &= ~HCR_TWE;
624 else
625 vcpu->arch.hcr_el2 |= HCR_TWE;
626
627 if (kvm_vcpu_should_clear_twi(vcpu))
628 vcpu->arch.hcr_el2 &= ~HCR_TWI;
629 else
630 vcpu->arch.hcr_el2 |= HCR_TWI;
631
632 vcpu_set_pauth_traps(vcpu);
633
634 if (is_protected_kvm_enabled()) {
635 kvm_call_hyp_nvhe(__pkvm_vcpu_load,
636 vcpu->kvm->arch.pkvm.handle,
637 vcpu->vcpu_idx, vcpu->arch.hcr_el2);
638 kvm_call_hyp(__vgic_v3_restore_vmcr_aprs,
639 &vcpu->arch.vgic_cpu.vgic_v3);
640 }
641
642 if (!cpumask_test_cpu(cpu, vcpu->kvm->arch.supported_cpus))
643 vcpu_set_on_unsupported_cpu(vcpu);
644 }
645
kvm_arch_vcpu_put(struct kvm_vcpu * vcpu)646 void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu)
647 {
648 if (is_protected_kvm_enabled()) {
649 kvm_call_hyp(__vgic_v3_save_vmcr_aprs,
650 &vcpu->arch.vgic_cpu.vgic_v3);
651 kvm_call_hyp_nvhe(__pkvm_vcpu_put);
652 }
653
654 kvm_vcpu_put_debug(vcpu);
655 kvm_arch_vcpu_put_fp(vcpu);
656 if (has_vhe())
657 kvm_vcpu_put_vhe(vcpu);
658 kvm_timer_vcpu_put(vcpu);
659 kvm_vgic_put(vcpu);
660 kvm_vcpu_pmu_restore_host(vcpu);
661 if (vcpu_has_nv(vcpu))
662 kvm_vcpu_put_hw_mmu(vcpu);
663 kvm_arm_vmid_clear_active();
664
665 vcpu_clear_on_unsupported_cpu(vcpu);
666 vcpu->cpu = -1;
667 }
668
__kvm_arm_vcpu_power_off(struct kvm_vcpu * vcpu)669 static void __kvm_arm_vcpu_power_off(struct kvm_vcpu *vcpu)
670 {
671 WRITE_ONCE(vcpu->arch.mp_state.mp_state, KVM_MP_STATE_STOPPED);
672 kvm_make_request(KVM_REQ_SLEEP, vcpu);
673 kvm_vcpu_kick(vcpu);
674 }
675
kvm_arm_vcpu_power_off(struct kvm_vcpu * vcpu)676 void kvm_arm_vcpu_power_off(struct kvm_vcpu *vcpu)
677 {
678 spin_lock(&vcpu->arch.mp_state_lock);
679 __kvm_arm_vcpu_power_off(vcpu);
680 spin_unlock(&vcpu->arch.mp_state_lock);
681 }
682
kvm_arm_vcpu_stopped(struct kvm_vcpu * vcpu)683 bool kvm_arm_vcpu_stopped(struct kvm_vcpu *vcpu)
684 {
685 return READ_ONCE(vcpu->arch.mp_state.mp_state) == KVM_MP_STATE_STOPPED;
686 }
687
kvm_arm_vcpu_suspend(struct kvm_vcpu * vcpu)688 static void kvm_arm_vcpu_suspend(struct kvm_vcpu *vcpu)
689 {
690 WRITE_ONCE(vcpu->arch.mp_state.mp_state, KVM_MP_STATE_SUSPENDED);
691 kvm_make_request(KVM_REQ_SUSPEND, vcpu);
692 kvm_vcpu_kick(vcpu);
693 }
694
kvm_arm_vcpu_suspended(struct kvm_vcpu * vcpu)695 static bool kvm_arm_vcpu_suspended(struct kvm_vcpu *vcpu)
696 {
697 return READ_ONCE(vcpu->arch.mp_state.mp_state) == KVM_MP_STATE_SUSPENDED;
698 }
699
kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu * vcpu,struct kvm_mp_state * mp_state)700 int kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu *vcpu,
701 struct kvm_mp_state *mp_state)
702 {
703 *mp_state = READ_ONCE(vcpu->arch.mp_state);
704
705 return 0;
706 }
707
kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu * vcpu,struct kvm_mp_state * mp_state)708 int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu,
709 struct kvm_mp_state *mp_state)
710 {
711 int ret = 0;
712
713 spin_lock(&vcpu->arch.mp_state_lock);
714
715 switch (mp_state->mp_state) {
716 case KVM_MP_STATE_RUNNABLE:
717 WRITE_ONCE(vcpu->arch.mp_state, *mp_state);
718 break;
719 case KVM_MP_STATE_STOPPED:
720 __kvm_arm_vcpu_power_off(vcpu);
721 break;
722 case KVM_MP_STATE_SUSPENDED:
723 kvm_arm_vcpu_suspend(vcpu);
724 break;
725 default:
726 ret = -EINVAL;
727 }
728
729 spin_unlock(&vcpu->arch.mp_state_lock);
730
731 return ret;
732 }
733
734 /**
735 * kvm_arch_vcpu_runnable - determine if the vcpu can be scheduled
736 * @v: The VCPU pointer
737 *
738 * If the guest CPU is not waiting for interrupts or an interrupt line is
739 * asserted, the CPU is by definition runnable.
740 */
kvm_arch_vcpu_runnable(struct kvm_vcpu * v)741 int kvm_arch_vcpu_runnable(struct kvm_vcpu *v)
742 {
743 bool irq_lines = *vcpu_hcr(v) & (HCR_VI | HCR_VF);
744 return ((irq_lines || kvm_vgic_vcpu_pending_irq(v))
745 && !kvm_arm_vcpu_stopped(v) && !v->arch.pause);
746 }
747
kvm_arch_vcpu_in_kernel(struct kvm_vcpu * vcpu)748 bool kvm_arch_vcpu_in_kernel(struct kvm_vcpu *vcpu)
749 {
750 return vcpu_mode_priv(vcpu);
751 }
752
753 #ifdef CONFIG_GUEST_PERF_EVENTS
kvm_arch_vcpu_get_ip(struct kvm_vcpu * vcpu)754 unsigned long kvm_arch_vcpu_get_ip(struct kvm_vcpu *vcpu)
755 {
756 return *vcpu_pc(vcpu);
757 }
758 #endif
759
kvm_init_mpidr_data(struct kvm * kvm)760 static void kvm_init_mpidr_data(struct kvm *kvm)
761 {
762 struct kvm_mpidr_data *data = NULL;
763 unsigned long c, mask, nr_entries;
764 u64 aff_set = 0, aff_clr = ~0UL;
765 struct kvm_vcpu *vcpu;
766
767 mutex_lock(&kvm->arch.config_lock);
768
769 if (rcu_access_pointer(kvm->arch.mpidr_data) ||
770 atomic_read(&kvm->online_vcpus) == 1)
771 goto out;
772
773 kvm_for_each_vcpu(c, vcpu, kvm) {
774 u64 aff = kvm_vcpu_get_mpidr_aff(vcpu);
775 aff_set |= aff;
776 aff_clr &= aff;
777 }
778
779 /*
780 * A significant bit can be either 0 or 1, and will only appear in
781 * aff_set. Use aff_clr to weed out the useless stuff.
782 */
783 mask = aff_set ^ aff_clr;
784 nr_entries = BIT_ULL(hweight_long(mask));
785
786 /*
787 * Don't let userspace fool us. If we need more than a single page
788 * to describe the compressed MPIDR array, just fall back to the
789 * iterative method. Single vcpu VMs do not need this either.
790 */
791 if (struct_size(data, cmpidr_to_idx, nr_entries) <= PAGE_SIZE)
792 data = kzalloc(struct_size(data, cmpidr_to_idx, nr_entries),
793 GFP_KERNEL_ACCOUNT);
794
795 if (!data)
796 goto out;
797
798 data->mpidr_mask = mask;
799
800 kvm_for_each_vcpu(c, vcpu, kvm) {
801 u64 aff = kvm_vcpu_get_mpidr_aff(vcpu);
802 u16 index = kvm_mpidr_index(data, aff);
803
804 data->cmpidr_to_idx[index] = c;
805 }
806
807 rcu_assign_pointer(kvm->arch.mpidr_data, data);
808 out:
809 mutex_unlock(&kvm->arch.config_lock);
810 }
811
812 /*
813 * Handle both the initialisation that is being done when the vcpu is
814 * run for the first time, as well as the updates that must be
815 * performed each time we get a new thread dealing with this vcpu.
816 */
kvm_arch_vcpu_run_pid_change(struct kvm_vcpu * vcpu)817 int kvm_arch_vcpu_run_pid_change(struct kvm_vcpu *vcpu)
818 {
819 struct kvm *kvm = vcpu->kvm;
820 int ret;
821
822 if (!kvm_vcpu_initialized(vcpu))
823 return -ENOEXEC;
824
825 if (!kvm_arm_vcpu_is_finalized(vcpu))
826 return -EPERM;
827
828 if (likely(vcpu_has_run_once(vcpu)))
829 return 0;
830
831 kvm_init_mpidr_data(kvm);
832
833 if (likely(irqchip_in_kernel(kvm))) {
834 /*
835 * Map the VGIC hardware resources before running a vcpu the
836 * first time on this VM.
837 */
838 ret = kvm_vgic_map_resources(kvm);
839 if (ret)
840 return ret;
841 }
842
843 ret = kvm_finalize_sys_regs(vcpu);
844 if (ret)
845 return ret;
846
847 if (vcpu_has_nv(vcpu)) {
848 ret = kvm_vcpu_allocate_vncr_tlb(vcpu);
849 if (ret)
850 return ret;
851
852 ret = kvm_vgic_vcpu_nv_init(vcpu);
853 if (ret)
854 return ret;
855 }
856
857 /*
858 * This needs to happen after any restriction has been applied
859 * to the feature set.
860 */
861 kvm_calculate_traps(vcpu);
862
863 ret = kvm_timer_enable(vcpu);
864 if (ret)
865 return ret;
866
867 if (kvm_vcpu_has_pmu(vcpu)) {
868 ret = kvm_arm_pmu_v3_enable(vcpu);
869 if (ret)
870 return ret;
871 }
872
873 if (is_protected_kvm_enabled()) {
874 ret = pkvm_create_hyp_vm(kvm);
875 if (ret)
876 return ret;
877
878 ret = pkvm_create_hyp_vcpu(vcpu);
879 if (ret)
880 return ret;
881 }
882
883 mutex_lock(&kvm->arch.config_lock);
884 set_bit(KVM_ARCH_FLAG_HAS_RAN_ONCE, &kvm->arch.flags);
885 mutex_unlock(&kvm->arch.config_lock);
886
887 return ret;
888 }
889
kvm_arch_intc_initialized(struct kvm * kvm)890 bool kvm_arch_intc_initialized(struct kvm *kvm)
891 {
892 return vgic_initialized(kvm);
893 }
894
kvm_arm_halt_guest(struct kvm * kvm)895 void kvm_arm_halt_guest(struct kvm *kvm)
896 {
897 unsigned long i;
898 struct kvm_vcpu *vcpu;
899
900 kvm_for_each_vcpu(i, vcpu, kvm)
901 vcpu->arch.pause = true;
902 kvm_make_all_cpus_request(kvm, KVM_REQ_SLEEP);
903 }
904
kvm_arm_resume_guest(struct kvm * kvm)905 void kvm_arm_resume_guest(struct kvm *kvm)
906 {
907 unsigned long i;
908 struct kvm_vcpu *vcpu;
909
910 kvm_for_each_vcpu(i, vcpu, kvm) {
911 vcpu->arch.pause = false;
912 __kvm_vcpu_wake_up(vcpu);
913 }
914 }
915
kvm_vcpu_sleep(struct kvm_vcpu * vcpu)916 static void kvm_vcpu_sleep(struct kvm_vcpu *vcpu)
917 {
918 struct rcuwait *wait = kvm_arch_vcpu_get_wait(vcpu);
919
920 rcuwait_wait_event(wait,
921 (!kvm_arm_vcpu_stopped(vcpu)) && (!vcpu->arch.pause),
922 TASK_INTERRUPTIBLE);
923
924 if (kvm_arm_vcpu_stopped(vcpu) || vcpu->arch.pause) {
925 /* Awaken to handle a signal, request we sleep again later. */
926 kvm_make_request(KVM_REQ_SLEEP, vcpu);
927 }
928
929 /*
930 * Make sure we will observe a potential reset request if we've
931 * observed a change to the power state. Pairs with the smp_wmb() in
932 * kvm_psci_vcpu_on().
933 */
934 smp_rmb();
935 }
936
937 /**
938 * kvm_vcpu_wfi - emulate Wait-For-Interrupt behavior
939 * @vcpu: The VCPU pointer
940 *
941 * Suspend execution of a vCPU until a valid wake event is detected, i.e. until
942 * the vCPU is runnable. The vCPU may or may not be scheduled out, depending
943 * on when a wake event arrives, e.g. there may already be a pending wake event.
944 */
kvm_vcpu_wfi(struct kvm_vcpu * vcpu)945 void kvm_vcpu_wfi(struct kvm_vcpu *vcpu)
946 {
947 /*
948 * Sync back the state of the GIC CPU interface so that we have
949 * the latest PMR and group enables. This ensures that
950 * kvm_arch_vcpu_runnable has up-to-date data to decide whether
951 * we have pending interrupts, e.g. when determining if the
952 * vCPU should block.
953 *
954 * For the same reason, we want to tell GICv4 that we need
955 * doorbells to be signalled, should an interrupt become pending.
956 */
957 preempt_disable();
958 vcpu_set_flag(vcpu, IN_WFI);
959 kvm_vgic_put(vcpu);
960 preempt_enable();
961
962 kvm_vcpu_halt(vcpu);
963 vcpu_clear_flag(vcpu, IN_WFIT);
964
965 preempt_disable();
966 vcpu_clear_flag(vcpu, IN_WFI);
967 kvm_vgic_load(vcpu);
968 preempt_enable();
969 }
970
kvm_vcpu_suspend(struct kvm_vcpu * vcpu)971 static int kvm_vcpu_suspend(struct kvm_vcpu *vcpu)
972 {
973 if (!kvm_arm_vcpu_suspended(vcpu))
974 return 1;
975
976 kvm_vcpu_wfi(vcpu);
977
978 /*
979 * The suspend state is sticky; we do not leave it until userspace
980 * explicitly marks the vCPU as runnable. Request that we suspend again
981 * later.
982 */
983 kvm_make_request(KVM_REQ_SUSPEND, vcpu);
984
985 /*
986 * Check to make sure the vCPU is actually runnable. If so, exit to
987 * userspace informing it of the wakeup condition.
988 */
989 if (kvm_arch_vcpu_runnable(vcpu)) {
990 memset(&vcpu->run->system_event, 0, sizeof(vcpu->run->system_event));
991 vcpu->run->system_event.type = KVM_SYSTEM_EVENT_WAKEUP;
992 vcpu->run->exit_reason = KVM_EXIT_SYSTEM_EVENT;
993 return 0;
994 }
995
996 /*
997 * Otherwise, we were unblocked to process a different event, such as a
998 * pending signal. Return 1 and allow kvm_arch_vcpu_ioctl_run() to
999 * process the event.
1000 */
1001 return 1;
1002 }
1003
1004 /**
1005 * check_vcpu_requests - check and handle pending vCPU requests
1006 * @vcpu: the VCPU pointer
1007 *
1008 * Return: 1 if we should enter the guest
1009 * 0 if we should exit to userspace
1010 * < 0 if we should exit to userspace, where the return value indicates
1011 * an error
1012 */
check_vcpu_requests(struct kvm_vcpu * vcpu)1013 static int check_vcpu_requests(struct kvm_vcpu *vcpu)
1014 {
1015 if (kvm_request_pending(vcpu)) {
1016 if (kvm_check_request(KVM_REQ_VM_DEAD, vcpu))
1017 return -EIO;
1018
1019 if (kvm_check_request(KVM_REQ_SLEEP, vcpu))
1020 kvm_vcpu_sleep(vcpu);
1021
1022 if (kvm_check_request(KVM_REQ_VCPU_RESET, vcpu))
1023 kvm_reset_vcpu(vcpu);
1024
1025 /*
1026 * Clear IRQ_PENDING requests that were made to guarantee
1027 * that a VCPU sees new virtual interrupts.
1028 */
1029 kvm_check_request(KVM_REQ_IRQ_PENDING, vcpu);
1030
1031 if (kvm_check_request(KVM_REQ_RECORD_STEAL, vcpu))
1032 kvm_update_stolen_time(vcpu);
1033
1034 if (kvm_check_request(KVM_REQ_RELOAD_GICv4, vcpu)) {
1035 /* The distributor enable bits were changed */
1036 preempt_disable();
1037 vgic_v4_put(vcpu);
1038 vgic_v4_load(vcpu);
1039 preempt_enable();
1040 }
1041
1042 if (kvm_check_request(KVM_REQ_RELOAD_PMU, vcpu))
1043 kvm_vcpu_reload_pmu(vcpu);
1044
1045 if (kvm_check_request(KVM_REQ_RESYNC_PMU_EL0, vcpu))
1046 kvm_vcpu_pmu_restore_guest(vcpu);
1047
1048 if (kvm_check_request(KVM_REQ_SUSPEND, vcpu))
1049 return kvm_vcpu_suspend(vcpu);
1050
1051 if (kvm_dirty_ring_check_request(vcpu))
1052 return 0;
1053
1054 check_nested_vcpu_requests(vcpu);
1055 }
1056
1057 return 1;
1058 }
1059
vcpu_mode_is_bad_32bit(struct kvm_vcpu * vcpu)1060 static bool vcpu_mode_is_bad_32bit(struct kvm_vcpu *vcpu)
1061 {
1062 if (likely(!vcpu_mode_is_32bit(vcpu)))
1063 return false;
1064
1065 if (vcpu_has_nv(vcpu))
1066 return true;
1067
1068 return !kvm_supports_32bit_el0();
1069 }
1070
1071 /**
1072 * kvm_vcpu_exit_request - returns true if the VCPU should *not* enter the guest
1073 * @vcpu: The VCPU pointer
1074 * @ret: Pointer to write optional return code
1075 *
1076 * Returns: true if the VCPU needs to return to a preemptible + interruptible
1077 * and skip guest entry.
1078 *
1079 * This function disambiguates between two different types of exits: exits to a
1080 * preemptible + interruptible kernel context and exits to userspace. For an
1081 * exit to userspace, this function will write the return code to ret and return
1082 * true. For an exit to preemptible + interruptible kernel context (i.e. check
1083 * for pending work and re-enter), return true without writing to ret.
1084 */
kvm_vcpu_exit_request(struct kvm_vcpu * vcpu,int * ret)1085 static bool kvm_vcpu_exit_request(struct kvm_vcpu *vcpu, int *ret)
1086 {
1087 struct kvm_run *run = vcpu->run;
1088
1089 /*
1090 * If we're using a userspace irqchip, then check if we need
1091 * to tell a userspace irqchip about timer or PMU level
1092 * changes and if so, exit to userspace (the actual level
1093 * state gets updated in kvm_timer_update_run and
1094 * kvm_pmu_update_run below).
1095 */
1096 if (unlikely(!irqchip_in_kernel(vcpu->kvm))) {
1097 if (kvm_timer_should_notify_user(vcpu) ||
1098 kvm_pmu_should_notify_user(vcpu)) {
1099 *ret = -EINTR;
1100 run->exit_reason = KVM_EXIT_INTR;
1101 return true;
1102 }
1103 }
1104
1105 if (unlikely(vcpu_on_unsupported_cpu(vcpu))) {
1106 run->exit_reason = KVM_EXIT_FAIL_ENTRY;
1107 run->fail_entry.hardware_entry_failure_reason = KVM_EXIT_FAIL_ENTRY_CPU_UNSUPPORTED;
1108 run->fail_entry.cpu = smp_processor_id();
1109 *ret = 0;
1110 return true;
1111 }
1112
1113 return kvm_request_pending(vcpu) ||
1114 xfer_to_guest_mode_work_pending();
1115 }
1116
1117 /*
1118 * Actually run the vCPU, entering an RCU extended quiescent state (EQS) while
1119 * the vCPU is running.
1120 *
1121 * This must be noinstr as instrumentation may make use of RCU, and this is not
1122 * safe during the EQS.
1123 */
kvm_arm_vcpu_enter_exit(struct kvm_vcpu * vcpu)1124 static int noinstr kvm_arm_vcpu_enter_exit(struct kvm_vcpu *vcpu)
1125 {
1126 int ret;
1127
1128 guest_state_enter_irqoff();
1129 ret = kvm_call_hyp_ret(__kvm_vcpu_run, vcpu);
1130 guest_state_exit_irqoff();
1131
1132 return ret;
1133 }
1134
1135 /**
1136 * kvm_arch_vcpu_ioctl_run - the main VCPU run function to execute guest code
1137 * @vcpu: The VCPU pointer
1138 *
1139 * This function is called through the VCPU_RUN ioctl called from user space. It
1140 * will execute VM code in a loop until the time slice for the process is used
1141 * or some emulation is needed from user space in which case the function will
1142 * return with return value 0 and with the kvm_run structure filled in with the
1143 * required data for the requested emulation.
1144 */
kvm_arch_vcpu_ioctl_run(struct kvm_vcpu * vcpu)1145 int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu)
1146 {
1147 struct kvm_run *run = vcpu->run;
1148 int ret;
1149
1150 if (run->exit_reason == KVM_EXIT_MMIO) {
1151 ret = kvm_handle_mmio_return(vcpu);
1152 if (ret <= 0)
1153 return ret;
1154 }
1155
1156 vcpu_load(vcpu);
1157
1158 if (!vcpu->wants_to_run) {
1159 ret = -EINTR;
1160 goto out;
1161 }
1162
1163 kvm_sigset_activate(vcpu);
1164
1165 ret = 1;
1166 run->exit_reason = KVM_EXIT_UNKNOWN;
1167 run->flags = 0;
1168 while (ret > 0) {
1169 /*
1170 * Check conditions before entering the guest
1171 */
1172 ret = xfer_to_guest_mode_handle_work(vcpu);
1173 if (!ret)
1174 ret = 1;
1175
1176 if (ret > 0)
1177 ret = check_vcpu_requests(vcpu);
1178
1179 /*
1180 * Preparing the interrupts to be injected also
1181 * involves poking the GIC, which must be done in a
1182 * non-preemptible context.
1183 */
1184 preempt_disable();
1185
1186 if (kvm_vcpu_has_pmu(vcpu))
1187 kvm_pmu_flush_hwstate(vcpu);
1188
1189 local_irq_disable();
1190
1191 kvm_vgic_flush_hwstate(vcpu);
1192
1193 kvm_pmu_update_vcpu_events(vcpu);
1194
1195 /*
1196 * Ensure we set mode to IN_GUEST_MODE after we disable
1197 * interrupts and before the final VCPU requests check.
1198 * See the comment in kvm_vcpu_exiting_guest_mode() and
1199 * Documentation/virt/kvm/vcpu-requests.rst
1200 */
1201 smp_store_mb(vcpu->mode, IN_GUEST_MODE);
1202
1203 if (ret <= 0 || kvm_vcpu_exit_request(vcpu, &ret)) {
1204 vcpu->mode = OUTSIDE_GUEST_MODE;
1205 isb(); /* Ensure work in x_flush_hwstate is committed */
1206 if (kvm_vcpu_has_pmu(vcpu))
1207 kvm_pmu_sync_hwstate(vcpu);
1208 if (unlikely(!irqchip_in_kernel(vcpu->kvm)))
1209 kvm_timer_sync_user(vcpu);
1210 kvm_vgic_sync_hwstate(vcpu);
1211 local_irq_enable();
1212 preempt_enable();
1213 continue;
1214 }
1215
1216 kvm_arch_vcpu_ctxflush_fp(vcpu);
1217
1218 /**************************************************************
1219 * Enter the guest
1220 */
1221 trace_kvm_entry(*vcpu_pc(vcpu));
1222 guest_timing_enter_irqoff();
1223
1224 ret = kvm_arm_vcpu_enter_exit(vcpu);
1225
1226 vcpu->mode = OUTSIDE_GUEST_MODE;
1227 vcpu->stat.exits++;
1228 /*
1229 * Back from guest
1230 *************************************************************/
1231
1232 /*
1233 * We must sync the PMU state before the vgic state so
1234 * that the vgic can properly sample the updated state of the
1235 * interrupt line.
1236 */
1237 if (kvm_vcpu_has_pmu(vcpu))
1238 kvm_pmu_sync_hwstate(vcpu);
1239
1240 /*
1241 * Sync the vgic state before syncing the timer state because
1242 * the timer code needs to know if the virtual timer
1243 * interrupts are active.
1244 */
1245 kvm_vgic_sync_hwstate(vcpu);
1246
1247 /*
1248 * Sync the timer hardware state before enabling interrupts as
1249 * we don't want vtimer interrupts to race with syncing the
1250 * timer virtual interrupt state.
1251 */
1252 if (unlikely(!irqchip_in_kernel(vcpu->kvm)))
1253 kvm_timer_sync_user(vcpu);
1254
1255 if (is_hyp_ctxt(vcpu))
1256 kvm_timer_sync_nested(vcpu);
1257
1258 kvm_arch_vcpu_ctxsync_fp(vcpu);
1259
1260 /*
1261 * We must ensure that any pending interrupts are taken before
1262 * we exit guest timing so that timer ticks are accounted as
1263 * guest time. Transiently unmask interrupts so that any
1264 * pending interrupts are taken.
1265 *
1266 * Per ARM DDI 0487G.b section D1.13.4, an ISB (or other
1267 * context synchronization event) is necessary to ensure that
1268 * pending interrupts are taken.
1269 */
1270 if (ARM_EXCEPTION_CODE(ret) == ARM_EXCEPTION_IRQ) {
1271 local_irq_enable();
1272 isb();
1273 local_irq_disable();
1274 }
1275
1276 guest_timing_exit_irqoff();
1277
1278 local_irq_enable();
1279
1280 trace_kvm_exit(ret, kvm_vcpu_trap_get_class(vcpu), *vcpu_pc(vcpu));
1281
1282 /* Exit types that need handling before we can be preempted */
1283 handle_exit_early(vcpu, ret);
1284
1285 preempt_enable();
1286
1287 /*
1288 * The ARMv8 architecture doesn't give the hypervisor
1289 * a mechanism to prevent a guest from dropping to AArch32 EL0
1290 * if implemented by the CPU. If we spot the guest in such
1291 * state and that we decided it wasn't supposed to do so (like
1292 * with the asymmetric AArch32 case), return to userspace with
1293 * a fatal error.
1294 */
1295 if (vcpu_mode_is_bad_32bit(vcpu)) {
1296 /*
1297 * As we have caught the guest red-handed, decide that
1298 * it isn't fit for purpose anymore by making the vcpu
1299 * invalid. The VMM can try and fix it by issuing a
1300 * KVM_ARM_VCPU_INIT if it really wants to.
1301 */
1302 vcpu_clear_flag(vcpu, VCPU_INITIALIZED);
1303 ret = ARM_EXCEPTION_IL;
1304 }
1305
1306 ret = handle_exit(vcpu, ret);
1307 }
1308
1309 /* Tell userspace about in-kernel device output levels */
1310 if (unlikely(!irqchip_in_kernel(vcpu->kvm))) {
1311 kvm_timer_update_run(vcpu);
1312 kvm_pmu_update_run(vcpu);
1313 }
1314
1315 kvm_sigset_deactivate(vcpu);
1316
1317 out:
1318 /*
1319 * In the unlikely event that we are returning to userspace
1320 * with pending exceptions or PC adjustment, commit these
1321 * adjustments in order to give userspace a consistent view of
1322 * the vcpu state. Note that this relies on __kvm_adjust_pc()
1323 * being preempt-safe on VHE.
1324 */
1325 if (unlikely(vcpu_get_flag(vcpu, PENDING_EXCEPTION) ||
1326 vcpu_get_flag(vcpu, INCREMENT_PC)))
1327 kvm_call_hyp(__kvm_adjust_pc, vcpu);
1328
1329 vcpu_put(vcpu);
1330 return ret;
1331 }
1332
vcpu_interrupt_line(struct kvm_vcpu * vcpu,int number,bool level)1333 static int vcpu_interrupt_line(struct kvm_vcpu *vcpu, int number, bool level)
1334 {
1335 int bit_index;
1336 bool set;
1337 unsigned long *hcr;
1338
1339 if (number == KVM_ARM_IRQ_CPU_IRQ)
1340 bit_index = __ffs(HCR_VI);
1341 else /* KVM_ARM_IRQ_CPU_FIQ */
1342 bit_index = __ffs(HCR_VF);
1343
1344 hcr = vcpu_hcr(vcpu);
1345 if (level)
1346 set = test_and_set_bit(bit_index, hcr);
1347 else
1348 set = test_and_clear_bit(bit_index, hcr);
1349
1350 /*
1351 * If we didn't change anything, no need to wake up or kick other CPUs
1352 */
1353 if (set == level)
1354 return 0;
1355
1356 /*
1357 * The vcpu irq_lines field was updated, wake up sleeping VCPUs and
1358 * trigger a world-switch round on the running physical CPU to set the
1359 * virtual IRQ/FIQ fields in the HCR appropriately.
1360 */
1361 kvm_make_request(KVM_REQ_IRQ_PENDING, vcpu);
1362 kvm_vcpu_kick(vcpu);
1363
1364 return 0;
1365 }
1366
kvm_vm_ioctl_irq_line(struct kvm * kvm,struct kvm_irq_level * irq_level,bool line_status)1367 int kvm_vm_ioctl_irq_line(struct kvm *kvm, struct kvm_irq_level *irq_level,
1368 bool line_status)
1369 {
1370 u32 irq = irq_level->irq;
1371 unsigned int irq_type, vcpu_id, irq_num;
1372 struct kvm_vcpu *vcpu = NULL;
1373 bool level = irq_level->level;
1374
1375 irq_type = (irq >> KVM_ARM_IRQ_TYPE_SHIFT) & KVM_ARM_IRQ_TYPE_MASK;
1376 vcpu_id = (irq >> KVM_ARM_IRQ_VCPU_SHIFT) & KVM_ARM_IRQ_VCPU_MASK;
1377 vcpu_id += ((irq >> KVM_ARM_IRQ_VCPU2_SHIFT) & KVM_ARM_IRQ_VCPU2_MASK) * (KVM_ARM_IRQ_VCPU_MASK + 1);
1378 irq_num = (irq >> KVM_ARM_IRQ_NUM_SHIFT) & KVM_ARM_IRQ_NUM_MASK;
1379
1380 trace_kvm_irq_line(irq_type, vcpu_id, irq_num, irq_level->level);
1381
1382 switch (irq_type) {
1383 case KVM_ARM_IRQ_TYPE_CPU:
1384 if (irqchip_in_kernel(kvm))
1385 return -ENXIO;
1386
1387 vcpu = kvm_get_vcpu_by_id(kvm, vcpu_id);
1388 if (!vcpu)
1389 return -EINVAL;
1390
1391 if (irq_num > KVM_ARM_IRQ_CPU_FIQ)
1392 return -EINVAL;
1393
1394 return vcpu_interrupt_line(vcpu, irq_num, level);
1395 case KVM_ARM_IRQ_TYPE_PPI:
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 < VGIC_NR_SGIS || irq_num >= VGIC_NR_PRIVATE_IRQS)
1404 return -EINVAL;
1405
1406 return kvm_vgic_inject_irq(kvm, vcpu, irq_num, level, NULL);
1407 case KVM_ARM_IRQ_TYPE_SPI:
1408 if (!irqchip_in_kernel(kvm))
1409 return -ENXIO;
1410
1411 if (irq_num < VGIC_NR_PRIVATE_IRQS)
1412 return -EINVAL;
1413
1414 return kvm_vgic_inject_irq(kvm, NULL, irq_num, level, NULL);
1415 }
1416
1417 return -EINVAL;
1418 }
1419
system_supported_vcpu_features(void)1420 static unsigned long system_supported_vcpu_features(void)
1421 {
1422 unsigned long features = KVM_VCPU_VALID_FEATURES;
1423
1424 if (!cpus_have_final_cap(ARM64_HAS_32BIT_EL1))
1425 clear_bit(KVM_ARM_VCPU_EL1_32BIT, &features);
1426
1427 if (!kvm_supports_guest_pmuv3())
1428 clear_bit(KVM_ARM_VCPU_PMU_V3, &features);
1429
1430 if (!system_supports_sve())
1431 clear_bit(KVM_ARM_VCPU_SVE, &features);
1432
1433 if (!kvm_has_full_ptr_auth()) {
1434 clear_bit(KVM_ARM_VCPU_PTRAUTH_ADDRESS, &features);
1435 clear_bit(KVM_ARM_VCPU_PTRAUTH_GENERIC, &features);
1436 }
1437
1438 if (!cpus_have_final_cap(ARM64_HAS_NESTED_VIRT))
1439 clear_bit(KVM_ARM_VCPU_HAS_EL2, &features);
1440
1441 return features;
1442 }
1443
kvm_vcpu_init_check_features(struct kvm_vcpu * vcpu,const struct kvm_vcpu_init * init)1444 static int kvm_vcpu_init_check_features(struct kvm_vcpu *vcpu,
1445 const struct kvm_vcpu_init *init)
1446 {
1447 unsigned long features = init->features[0];
1448 int i;
1449
1450 if (features & ~KVM_VCPU_VALID_FEATURES)
1451 return -ENOENT;
1452
1453 for (i = 1; i < ARRAY_SIZE(init->features); i++) {
1454 if (init->features[i])
1455 return -ENOENT;
1456 }
1457
1458 if (features & ~system_supported_vcpu_features())
1459 return -EINVAL;
1460
1461 /*
1462 * For now make sure that both address/generic pointer authentication
1463 * features are requested by the userspace together.
1464 */
1465 if (test_bit(KVM_ARM_VCPU_PTRAUTH_ADDRESS, &features) !=
1466 test_bit(KVM_ARM_VCPU_PTRAUTH_GENERIC, &features))
1467 return -EINVAL;
1468
1469 if (!test_bit(KVM_ARM_VCPU_EL1_32BIT, &features))
1470 return 0;
1471
1472 /* MTE is incompatible with AArch32 */
1473 if (kvm_has_mte(vcpu->kvm))
1474 return -EINVAL;
1475
1476 /* NV is incompatible with AArch32 */
1477 if (test_bit(KVM_ARM_VCPU_HAS_EL2, &features))
1478 return -EINVAL;
1479
1480 return 0;
1481 }
1482
kvm_vcpu_init_changed(struct kvm_vcpu * vcpu,const struct kvm_vcpu_init * init)1483 static bool kvm_vcpu_init_changed(struct kvm_vcpu *vcpu,
1484 const struct kvm_vcpu_init *init)
1485 {
1486 unsigned long features = init->features[0];
1487
1488 return !bitmap_equal(vcpu->kvm->arch.vcpu_features, &features,
1489 KVM_VCPU_MAX_FEATURES);
1490 }
1491
kvm_setup_vcpu(struct kvm_vcpu * vcpu)1492 static int kvm_setup_vcpu(struct kvm_vcpu *vcpu)
1493 {
1494 struct kvm *kvm = vcpu->kvm;
1495 int ret = 0;
1496
1497 /*
1498 * When the vCPU has a PMU, but no PMU is set for the guest
1499 * yet, set the default one.
1500 */
1501 if (kvm_vcpu_has_pmu(vcpu) && !kvm->arch.arm_pmu)
1502 ret = kvm_arm_set_default_pmu(kvm);
1503
1504 /* Prepare for nested if required */
1505 if (!ret && vcpu_has_nv(vcpu))
1506 ret = kvm_vcpu_init_nested(vcpu);
1507
1508 return ret;
1509 }
1510
__kvm_vcpu_set_target(struct kvm_vcpu * vcpu,const struct kvm_vcpu_init * init)1511 static int __kvm_vcpu_set_target(struct kvm_vcpu *vcpu,
1512 const struct kvm_vcpu_init *init)
1513 {
1514 unsigned long features = init->features[0];
1515 struct kvm *kvm = vcpu->kvm;
1516 int ret = -EINVAL;
1517
1518 mutex_lock(&kvm->arch.config_lock);
1519
1520 if (test_bit(KVM_ARCH_FLAG_VCPU_FEATURES_CONFIGURED, &kvm->arch.flags) &&
1521 kvm_vcpu_init_changed(vcpu, init))
1522 goto out_unlock;
1523
1524 bitmap_copy(kvm->arch.vcpu_features, &features, KVM_VCPU_MAX_FEATURES);
1525
1526 ret = kvm_setup_vcpu(vcpu);
1527 if (ret)
1528 goto out_unlock;
1529
1530 /* Now we know what it is, we can reset it. */
1531 kvm_reset_vcpu(vcpu);
1532
1533 set_bit(KVM_ARCH_FLAG_VCPU_FEATURES_CONFIGURED, &kvm->arch.flags);
1534 vcpu_set_flag(vcpu, VCPU_INITIALIZED);
1535 ret = 0;
1536 out_unlock:
1537 mutex_unlock(&kvm->arch.config_lock);
1538 return ret;
1539 }
1540
kvm_vcpu_set_target(struct kvm_vcpu * vcpu,const struct kvm_vcpu_init * init)1541 static int kvm_vcpu_set_target(struct kvm_vcpu *vcpu,
1542 const struct kvm_vcpu_init *init)
1543 {
1544 int ret;
1545
1546 if (init->target != KVM_ARM_TARGET_GENERIC_V8 &&
1547 init->target != kvm_target_cpu())
1548 return -EINVAL;
1549
1550 ret = kvm_vcpu_init_check_features(vcpu, init);
1551 if (ret)
1552 return ret;
1553
1554 if (!kvm_vcpu_initialized(vcpu))
1555 return __kvm_vcpu_set_target(vcpu, init);
1556
1557 if (kvm_vcpu_init_changed(vcpu, init))
1558 return -EINVAL;
1559
1560 kvm_reset_vcpu(vcpu);
1561 return 0;
1562 }
1563
kvm_arch_vcpu_ioctl_vcpu_init(struct kvm_vcpu * vcpu,struct kvm_vcpu_init * init)1564 static int kvm_arch_vcpu_ioctl_vcpu_init(struct kvm_vcpu *vcpu,
1565 struct kvm_vcpu_init *init)
1566 {
1567 bool power_off = false;
1568 int ret;
1569
1570 /*
1571 * Treat the power-off vCPU feature as ephemeral. Clear the bit to avoid
1572 * reflecting it in the finalized feature set, thus limiting its scope
1573 * to a single KVM_ARM_VCPU_INIT call.
1574 */
1575 if (init->features[0] & BIT(KVM_ARM_VCPU_POWER_OFF)) {
1576 init->features[0] &= ~BIT(KVM_ARM_VCPU_POWER_OFF);
1577 power_off = true;
1578 }
1579
1580 ret = kvm_vcpu_set_target(vcpu, init);
1581 if (ret)
1582 return ret;
1583
1584 /*
1585 * Ensure a rebooted VM will fault in RAM pages and detect if the
1586 * guest MMU is turned off and flush the caches as needed.
1587 *
1588 * S2FWB enforces all memory accesses to RAM being cacheable,
1589 * ensuring that the data side is always coherent. We still
1590 * need to invalidate the I-cache though, as FWB does *not*
1591 * imply CTR_EL0.DIC.
1592 */
1593 if (vcpu_has_run_once(vcpu)) {
1594 if (!cpus_have_final_cap(ARM64_HAS_STAGE2_FWB))
1595 stage2_unmap_vm(vcpu->kvm);
1596 else
1597 icache_inval_all_pou();
1598 }
1599
1600 vcpu_reset_hcr(vcpu);
1601
1602 /*
1603 * Handle the "start in power-off" case.
1604 */
1605 spin_lock(&vcpu->arch.mp_state_lock);
1606
1607 if (power_off)
1608 __kvm_arm_vcpu_power_off(vcpu);
1609 else
1610 WRITE_ONCE(vcpu->arch.mp_state.mp_state, KVM_MP_STATE_RUNNABLE);
1611
1612 spin_unlock(&vcpu->arch.mp_state_lock);
1613
1614 return 0;
1615 }
1616
kvm_arm_vcpu_set_attr(struct kvm_vcpu * vcpu,struct kvm_device_attr * attr)1617 static int kvm_arm_vcpu_set_attr(struct kvm_vcpu *vcpu,
1618 struct kvm_device_attr *attr)
1619 {
1620 int ret = -ENXIO;
1621
1622 switch (attr->group) {
1623 default:
1624 ret = kvm_arm_vcpu_arch_set_attr(vcpu, attr);
1625 break;
1626 }
1627
1628 return ret;
1629 }
1630
kvm_arm_vcpu_get_attr(struct kvm_vcpu * vcpu,struct kvm_device_attr * attr)1631 static int kvm_arm_vcpu_get_attr(struct kvm_vcpu *vcpu,
1632 struct kvm_device_attr *attr)
1633 {
1634 int ret = -ENXIO;
1635
1636 switch (attr->group) {
1637 default:
1638 ret = kvm_arm_vcpu_arch_get_attr(vcpu, attr);
1639 break;
1640 }
1641
1642 return ret;
1643 }
1644
kvm_arm_vcpu_has_attr(struct kvm_vcpu * vcpu,struct kvm_device_attr * attr)1645 static int kvm_arm_vcpu_has_attr(struct kvm_vcpu *vcpu,
1646 struct kvm_device_attr *attr)
1647 {
1648 int ret = -ENXIO;
1649
1650 switch (attr->group) {
1651 default:
1652 ret = kvm_arm_vcpu_arch_has_attr(vcpu, attr);
1653 break;
1654 }
1655
1656 return ret;
1657 }
1658
kvm_arm_vcpu_get_events(struct kvm_vcpu * vcpu,struct kvm_vcpu_events * events)1659 static int kvm_arm_vcpu_get_events(struct kvm_vcpu *vcpu,
1660 struct kvm_vcpu_events *events)
1661 {
1662 memset(events, 0, sizeof(*events));
1663
1664 return __kvm_arm_vcpu_get_events(vcpu, events);
1665 }
1666
kvm_arm_vcpu_set_events(struct kvm_vcpu * vcpu,struct kvm_vcpu_events * events)1667 static int kvm_arm_vcpu_set_events(struct kvm_vcpu *vcpu,
1668 struct kvm_vcpu_events *events)
1669 {
1670 int i;
1671
1672 /* check whether the reserved field is zero */
1673 for (i = 0; i < ARRAY_SIZE(events->reserved); i++)
1674 if (events->reserved[i])
1675 return -EINVAL;
1676
1677 /* check whether the pad field is zero */
1678 for (i = 0; i < ARRAY_SIZE(events->exception.pad); i++)
1679 if (events->exception.pad[i])
1680 return -EINVAL;
1681
1682 return __kvm_arm_vcpu_set_events(vcpu, events);
1683 }
1684
kvm_arch_vcpu_ioctl(struct file * filp,unsigned int ioctl,unsigned long arg)1685 long kvm_arch_vcpu_ioctl(struct file *filp,
1686 unsigned int ioctl, unsigned long arg)
1687 {
1688 struct kvm_vcpu *vcpu = filp->private_data;
1689 void __user *argp = (void __user *)arg;
1690 struct kvm_device_attr attr;
1691 long r;
1692
1693 switch (ioctl) {
1694 case KVM_ARM_VCPU_INIT: {
1695 struct kvm_vcpu_init init;
1696
1697 r = -EFAULT;
1698 if (copy_from_user(&init, argp, sizeof(init)))
1699 break;
1700
1701 r = kvm_arch_vcpu_ioctl_vcpu_init(vcpu, &init);
1702 break;
1703 }
1704 case KVM_SET_ONE_REG:
1705 case KVM_GET_ONE_REG: {
1706 struct kvm_one_reg reg;
1707
1708 r = -ENOEXEC;
1709 if (unlikely(!kvm_vcpu_initialized(vcpu)))
1710 break;
1711
1712 r = -EFAULT;
1713 if (copy_from_user(®, argp, sizeof(reg)))
1714 break;
1715
1716 /*
1717 * We could owe a reset due to PSCI. Handle the pending reset
1718 * here to ensure userspace register accesses are ordered after
1719 * the reset.
1720 */
1721 if (kvm_check_request(KVM_REQ_VCPU_RESET, vcpu))
1722 kvm_reset_vcpu(vcpu);
1723
1724 if (ioctl == KVM_SET_ONE_REG)
1725 r = kvm_arm_set_reg(vcpu, ®);
1726 else
1727 r = kvm_arm_get_reg(vcpu, ®);
1728 break;
1729 }
1730 case KVM_GET_REG_LIST: {
1731 struct kvm_reg_list __user *user_list = argp;
1732 struct kvm_reg_list reg_list;
1733 unsigned n;
1734
1735 r = -ENOEXEC;
1736 if (unlikely(!kvm_vcpu_initialized(vcpu)))
1737 break;
1738
1739 r = -EPERM;
1740 if (!kvm_arm_vcpu_is_finalized(vcpu))
1741 break;
1742
1743 r = -EFAULT;
1744 if (copy_from_user(®_list, user_list, sizeof(reg_list)))
1745 break;
1746 n = reg_list.n;
1747 reg_list.n = kvm_arm_num_regs(vcpu);
1748 if (copy_to_user(user_list, ®_list, sizeof(reg_list)))
1749 break;
1750 r = -E2BIG;
1751 if (n < reg_list.n)
1752 break;
1753 r = kvm_arm_copy_reg_indices(vcpu, user_list->reg);
1754 break;
1755 }
1756 case KVM_SET_DEVICE_ATTR: {
1757 r = -EFAULT;
1758 if (copy_from_user(&attr, argp, sizeof(attr)))
1759 break;
1760 r = kvm_arm_vcpu_set_attr(vcpu, &attr);
1761 break;
1762 }
1763 case KVM_GET_DEVICE_ATTR: {
1764 r = -EFAULT;
1765 if (copy_from_user(&attr, argp, sizeof(attr)))
1766 break;
1767 r = kvm_arm_vcpu_get_attr(vcpu, &attr);
1768 break;
1769 }
1770 case KVM_HAS_DEVICE_ATTR: {
1771 r = -EFAULT;
1772 if (copy_from_user(&attr, argp, sizeof(attr)))
1773 break;
1774 r = kvm_arm_vcpu_has_attr(vcpu, &attr);
1775 break;
1776 }
1777 case KVM_GET_VCPU_EVENTS: {
1778 struct kvm_vcpu_events events;
1779
1780 if (kvm_arm_vcpu_get_events(vcpu, &events))
1781 return -EINVAL;
1782
1783 if (copy_to_user(argp, &events, sizeof(events)))
1784 return -EFAULT;
1785
1786 return 0;
1787 }
1788 case KVM_SET_VCPU_EVENTS: {
1789 struct kvm_vcpu_events events;
1790
1791 if (copy_from_user(&events, argp, sizeof(events)))
1792 return -EFAULT;
1793
1794 return kvm_arm_vcpu_set_events(vcpu, &events);
1795 }
1796 case KVM_ARM_VCPU_FINALIZE: {
1797 int what;
1798
1799 if (!kvm_vcpu_initialized(vcpu))
1800 return -ENOEXEC;
1801
1802 if (get_user(what, (const int __user *)argp))
1803 return -EFAULT;
1804
1805 return kvm_arm_vcpu_finalize(vcpu, what);
1806 }
1807 default:
1808 r = -EINVAL;
1809 }
1810
1811 return r;
1812 }
1813
kvm_arch_sync_dirty_log(struct kvm * kvm,struct kvm_memory_slot * memslot)1814 void kvm_arch_sync_dirty_log(struct kvm *kvm, struct kvm_memory_slot *memslot)
1815 {
1816
1817 }
1818
kvm_vm_ioctl_set_device_addr(struct kvm * kvm,struct kvm_arm_device_addr * dev_addr)1819 static int kvm_vm_ioctl_set_device_addr(struct kvm *kvm,
1820 struct kvm_arm_device_addr *dev_addr)
1821 {
1822 switch (FIELD_GET(KVM_ARM_DEVICE_ID_MASK, dev_addr->id)) {
1823 case KVM_ARM_DEVICE_VGIC_V2:
1824 if (!vgic_present)
1825 return -ENXIO;
1826 return kvm_set_legacy_vgic_v2_addr(kvm, dev_addr);
1827 default:
1828 return -ENODEV;
1829 }
1830 }
1831
kvm_vm_has_attr(struct kvm * kvm,struct kvm_device_attr * attr)1832 static int kvm_vm_has_attr(struct kvm *kvm, struct kvm_device_attr *attr)
1833 {
1834 switch (attr->group) {
1835 case KVM_ARM_VM_SMCCC_CTRL:
1836 return kvm_vm_smccc_has_attr(kvm, attr);
1837 default:
1838 return -ENXIO;
1839 }
1840 }
1841
kvm_vm_set_attr(struct kvm * kvm,struct kvm_device_attr * attr)1842 static int kvm_vm_set_attr(struct kvm *kvm, struct kvm_device_attr *attr)
1843 {
1844 switch (attr->group) {
1845 case KVM_ARM_VM_SMCCC_CTRL:
1846 return kvm_vm_smccc_set_attr(kvm, attr);
1847 default:
1848 return -ENXIO;
1849 }
1850 }
1851
kvm_arch_vm_ioctl(struct file * filp,unsigned int ioctl,unsigned long arg)1852 int kvm_arch_vm_ioctl(struct file *filp, unsigned int ioctl, unsigned long arg)
1853 {
1854 struct kvm *kvm = filp->private_data;
1855 void __user *argp = (void __user *)arg;
1856 struct kvm_device_attr attr;
1857
1858 switch (ioctl) {
1859 case KVM_CREATE_IRQCHIP: {
1860 int ret;
1861 if (!vgic_present)
1862 return -ENXIO;
1863 mutex_lock(&kvm->lock);
1864 ret = kvm_vgic_create(kvm, KVM_DEV_TYPE_ARM_VGIC_V2);
1865 mutex_unlock(&kvm->lock);
1866 return ret;
1867 }
1868 case KVM_ARM_SET_DEVICE_ADDR: {
1869 struct kvm_arm_device_addr dev_addr;
1870
1871 if (copy_from_user(&dev_addr, argp, sizeof(dev_addr)))
1872 return -EFAULT;
1873 return kvm_vm_ioctl_set_device_addr(kvm, &dev_addr);
1874 }
1875 case KVM_ARM_PREFERRED_TARGET: {
1876 struct kvm_vcpu_init init = {
1877 .target = KVM_ARM_TARGET_GENERIC_V8,
1878 };
1879
1880 if (copy_to_user(argp, &init, sizeof(init)))
1881 return -EFAULT;
1882
1883 return 0;
1884 }
1885 case KVM_ARM_MTE_COPY_TAGS: {
1886 struct kvm_arm_copy_mte_tags copy_tags;
1887
1888 if (copy_from_user(©_tags, argp, sizeof(copy_tags)))
1889 return -EFAULT;
1890 return kvm_vm_ioctl_mte_copy_tags(kvm, ©_tags);
1891 }
1892 case KVM_ARM_SET_COUNTER_OFFSET: {
1893 struct kvm_arm_counter_offset offset;
1894
1895 if (copy_from_user(&offset, argp, sizeof(offset)))
1896 return -EFAULT;
1897 return kvm_vm_ioctl_set_counter_offset(kvm, &offset);
1898 }
1899 case KVM_HAS_DEVICE_ATTR: {
1900 if (copy_from_user(&attr, argp, sizeof(attr)))
1901 return -EFAULT;
1902
1903 return kvm_vm_has_attr(kvm, &attr);
1904 }
1905 case KVM_SET_DEVICE_ATTR: {
1906 if (copy_from_user(&attr, argp, sizeof(attr)))
1907 return -EFAULT;
1908
1909 return kvm_vm_set_attr(kvm, &attr);
1910 }
1911 case KVM_ARM_GET_REG_WRITABLE_MASKS: {
1912 struct reg_mask_range range;
1913
1914 if (copy_from_user(&range, argp, sizeof(range)))
1915 return -EFAULT;
1916 return kvm_vm_ioctl_get_reg_writable_masks(kvm, &range);
1917 }
1918 default:
1919 return -EINVAL;
1920 }
1921 }
1922
nvhe_percpu_size(void)1923 static unsigned long nvhe_percpu_size(void)
1924 {
1925 return (unsigned long)CHOOSE_NVHE_SYM(__per_cpu_end) -
1926 (unsigned long)CHOOSE_NVHE_SYM(__per_cpu_start);
1927 }
1928
nvhe_percpu_order(void)1929 static unsigned long nvhe_percpu_order(void)
1930 {
1931 unsigned long size = nvhe_percpu_size();
1932
1933 return size ? get_order(size) : 0;
1934 }
1935
pkvm_host_sve_state_order(void)1936 static size_t pkvm_host_sve_state_order(void)
1937 {
1938 return get_order(pkvm_host_sve_state_size());
1939 }
1940
1941 /* A lookup table holding the hypervisor VA for each vector slot */
1942 static void *hyp_spectre_vector_selector[BP_HARDEN_EL2_SLOTS];
1943
kvm_init_vector_slot(void * base,enum arm64_hyp_spectre_vector slot)1944 static void kvm_init_vector_slot(void *base, enum arm64_hyp_spectre_vector slot)
1945 {
1946 hyp_spectre_vector_selector[slot] = __kvm_vector_slot2addr(base, slot);
1947 }
1948
kvm_init_vector_slots(void)1949 static int kvm_init_vector_slots(void)
1950 {
1951 int err;
1952 void *base;
1953
1954 base = kern_hyp_va(kvm_ksym_ref(__kvm_hyp_vector));
1955 kvm_init_vector_slot(base, HYP_VECTOR_DIRECT);
1956
1957 base = kern_hyp_va(kvm_ksym_ref(__bp_harden_hyp_vecs));
1958 kvm_init_vector_slot(base, HYP_VECTOR_SPECTRE_DIRECT);
1959
1960 if (kvm_system_needs_idmapped_vectors() &&
1961 !is_protected_kvm_enabled()) {
1962 err = create_hyp_exec_mappings(__pa_symbol(__bp_harden_hyp_vecs),
1963 __BP_HARDEN_HYP_VECS_SZ, &base);
1964 if (err)
1965 return err;
1966 }
1967
1968 kvm_init_vector_slot(base, HYP_VECTOR_INDIRECT);
1969 kvm_init_vector_slot(base, HYP_VECTOR_SPECTRE_INDIRECT);
1970 return 0;
1971 }
1972
cpu_prepare_hyp_mode(int cpu,u32 hyp_va_bits)1973 static void __init cpu_prepare_hyp_mode(int cpu, u32 hyp_va_bits)
1974 {
1975 struct kvm_nvhe_init_params *params = per_cpu_ptr_nvhe_sym(kvm_init_params, cpu);
1976 unsigned long tcr;
1977
1978 /*
1979 * Calculate the raw per-cpu offset without a translation from the
1980 * kernel's mapping to the linear mapping, and store it in tpidr_el2
1981 * so that we can use adr_l to access per-cpu variables in EL2.
1982 * Also drop the KASAN tag which gets in the way...
1983 */
1984 params->tpidr_el2 = (unsigned long)kasan_reset_tag(per_cpu_ptr_nvhe_sym(__per_cpu_start, cpu)) -
1985 (unsigned long)kvm_ksym_ref(CHOOSE_NVHE_SYM(__per_cpu_start));
1986
1987 params->mair_el2 = read_sysreg(mair_el1);
1988
1989 tcr = read_sysreg(tcr_el1);
1990 if (cpus_have_final_cap(ARM64_KVM_HVHE)) {
1991 tcr &= ~(TCR_HD | TCR_HA | TCR_A1 | TCR_T0SZ_MASK);
1992 tcr |= TCR_EPD1_MASK;
1993 } else {
1994 unsigned long ips = FIELD_GET(TCR_IPS_MASK, tcr);
1995
1996 tcr &= TCR_EL2_MASK;
1997 tcr |= TCR_EL2_RES1 | FIELD_PREP(TCR_EL2_PS_MASK, ips);
1998 if (lpa2_is_enabled())
1999 tcr |= TCR_EL2_DS;
2000 }
2001 tcr |= TCR_T0SZ(hyp_va_bits);
2002 params->tcr_el2 = tcr;
2003
2004 params->pgd_pa = kvm_mmu_get_httbr();
2005 if (is_protected_kvm_enabled())
2006 params->hcr_el2 = HCR_HOST_NVHE_PROTECTED_FLAGS;
2007 else
2008 params->hcr_el2 = HCR_HOST_NVHE_FLAGS;
2009 if (cpus_have_final_cap(ARM64_KVM_HVHE))
2010 params->hcr_el2 |= HCR_E2H;
2011 params->vttbr = params->vtcr = 0;
2012
2013 /*
2014 * Flush the init params from the data cache because the struct will
2015 * be read while the MMU is off.
2016 */
2017 kvm_flush_dcache_to_poc(params, sizeof(*params));
2018 }
2019
hyp_install_host_vector(void)2020 static void hyp_install_host_vector(void)
2021 {
2022 struct kvm_nvhe_init_params *params;
2023 struct arm_smccc_res res;
2024
2025 /* Switch from the HYP stub to our own HYP init vector */
2026 __hyp_set_vectors(kvm_get_idmap_vector());
2027
2028 /*
2029 * Call initialization code, and switch to the full blown HYP code.
2030 * If the cpucaps haven't been finalized yet, something has gone very
2031 * wrong, and hyp will crash and burn when it uses any
2032 * cpus_have_*_cap() wrapper.
2033 */
2034 BUG_ON(!system_capabilities_finalized());
2035 params = this_cpu_ptr_nvhe_sym(kvm_init_params);
2036 arm_smccc_1_1_hvc(KVM_HOST_SMCCC_FUNC(__kvm_hyp_init), virt_to_phys(params), &res);
2037 WARN_ON(res.a0 != SMCCC_RET_SUCCESS);
2038 }
2039
cpu_init_hyp_mode(void)2040 static void cpu_init_hyp_mode(void)
2041 {
2042 hyp_install_host_vector();
2043
2044 /*
2045 * Disabling SSBD on a non-VHE system requires us to enable SSBS
2046 * at EL2.
2047 */
2048 if (this_cpu_has_cap(ARM64_SSBS) &&
2049 arm64_get_spectre_v4_state() == SPECTRE_VULNERABLE) {
2050 kvm_call_hyp_nvhe(__kvm_enable_ssbs);
2051 }
2052 }
2053
cpu_hyp_reset(void)2054 static void cpu_hyp_reset(void)
2055 {
2056 if (!is_kernel_in_hyp_mode())
2057 __hyp_reset_vectors();
2058 }
2059
2060 /*
2061 * EL2 vectors can be mapped and rerouted in a number of ways,
2062 * depending on the kernel configuration and CPU present:
2063 *
2064 * - If the CPU is affected by Spectre-v2, the hardening sequence is
2065 * placed in one of the vector slots, which is executed before jumping
2066 * to the real vectors.
2067 *
2068 * - If the CPU also has the ARM64_SPECTRE_V3A cap, the slot
2069 * containing the hardening sequence is mapped next to the idmap page,
2070 * and executed before jumping to the real vectors.
2071 *
2072 * - If the CPU only has the ARM64_SPECTRE_V3A cap, then an
2073 * empty slot is selected, mapped next to the idmap page, and
2074 * executed before jumping to the real vectors.
2075 *
2076 * Note that ARM64_SPECTRE_V3A is somewhat incompatible with
2077 * VHE, as we don't have hypervisor-specific mappings. If the system
2078 * is VHE and yet selects this capability, it will be ignored.
2079 */
cpu_set_hyp_vector(void)2080 static void cpu_set_hyp_vector(void)
2081 {
2082 struct bp_hardening_data *data = this_cpu_ptr(&bp_hardening_data);
2083 void *vector = hyp_spectre_vector_selector[data->slot];
2084
2085 if (!is_protected_kvm_enabled())
2086 *this_cpu_ptr_hyp_sym(kvm_hyp_vector) = (unsigned long)vector;
2087 else
2088 kvm_call_hyp_nvhe(__pkvm_cpu_set_vector, data->slot);
2089 }
2090
cpu_hyp_init_context(void)2091 static void cpu_hyp_init_context(void)
2092 {
2093 kvm_init_host_cpu_context(host_data_ptr(host_ctxt));
2094 kvm_init_host_debug_data();
2095
2096 if (!is_kernel_in_hyp_mode())
2097 cpu_init_hyp_mode();
2098 }
2099
cpu_hyp_init_features(void)2100 static void cpu_hyp_init_features(void)
2101 {
2102 cpu_set_hyp_vector();
2103
2104 if (is_kernel_in_hyp_mode())
2105 kvm_timer_init_vhe();
2106
2107 if (vgic_present)
2108 kvm_vgic_init_cpu_hardware();
2109 }
2110
cpu_hyp_reinit(void)2111 static void cpu_hyp_reinit(void)
2112 {
2113 cpu_hyp_reset();
2114 cpu_hyp_init_context();
2115 cpu_hyp_init_features();
2116 }
2117
cpu_hyp_init(void * discard)2118 static void cpu_hyp_init(void *discard)
2119 {
2120 if (!__this_cpu_read(kvm_hyp_initialized)) {
2121 cpu_hyp_reinit();
2122 __this_cpu_write(kvm_hyp_initialized, 1);
2123 }
2124 }
2125
cpu_hyp_uninit(void * discard)2126 static void cpu_hyp_uninit(void *discard)
2127 {
2128 if (!is_protected_kvm_enabled() && __this_cpu_read(kvm_hyp_initialized)) {
2129 cpu_hyp_reset();
2130 __this_cpu_write(kvm_hyp_initialized, 0);
2131 }
2132 }
2133
kvm_arch_enable_virtualization_cpu(void)2134 int kvm_arch_enable_virtualization_cpu(void)
2135 {
2136 /*
2137 * Most calls to this function are made with migration
2138 * disabled, but not with preemption disabled. The former is
2139 * enough to ensure correctness, but most of the helpers
2140 * expect the later and will throw a tantrum otherwise.
2141 */
2142 preempt_disable();
2143
2144 cpu_hyp_init(NULL);
2145
2146 kvm_vgic_cpu_up();
2147 kvm_timer_cpu_up();
2148
2149 preempt_enable();
2150
2151 return 0;
2152 }
2153
kvm_arch_disable_virtualization_cpu(void)2154 void kvm_arch_disable_virtualization_cpu(void)
2155 {
2156 kvm_timer_cpu_down();
2157 kvm_vgic_cpu_down();
2158
2159 if (!is_protected_kvm_enabled())
2160 cpu_hyp_uninit(NULL);
2161 }
2162
2163 #ifdef CONFIG_CPU_PM
hyp_init_cpu_pm_notifier(struct notifier_block * self,unsigned long cmd,void * v)2164 static int hyp_init_cpu_pm_notifier(struct notifier_block *self,
2165 unsigned long cmd,
2166 void *v)
2167 {
2168 /*
2169 * kvm_hyp_initialized is left with its old value over
2170 * PM_ENTER->PM_EXIT. It is used to indicate PM_EXIT should
2171 * re-enable hyp.
2172 */
2173 switch (cmd) {
2174 case CPU_PM_ENTER:
2175 if (__this_cpu_read(kvm_hyp_initialized))
2176 /*
2177 * don't update kvm_hyp_initialized here
2178 * so that the hyp will be re-enabled
2179 * when we resume. See below.
2180 */
2181 cpu_hyp_reset();
2182
2183 return NOTIFY_OK;
2184 case CPU_PM_ENTER_FAILED:
2185 case CPU_PM_EXIT:
2186 if (__this_cpu_read(kvm_hyp_initialized))
2187 /* The hyp was enabled before suspend. */
2188 cpu_hyp_reinit();
2189
2190 return NOTIFY_OK;
2191
2192 default:
2193 return NOTIFY_DONE;
2194 }
2195 }
2196
2197 static struct notifier_block hyp_init_cpu_pm_nb = {
2198 .notifier_call = hyp_init_cpu_pm_notifier,
2199 };
2200
hyp_cpu_pm_init(void)2201 static void __init hyp_cpu_pm_init(void)
2202 {
2203 if (!is_protected_kvm_enabled())
2204 cpu_pm_register_notifier(&hyp_init_cpu_pm_nb);
2205 }
hyp_cpu_pm_exit(void)2206 static void __init hyp_cpu_pm_exit(void)
2207 {
2208 if (!is_protected_kvm_enabled())
2209 cpu_pm_unregister_notifier(&hyp_init_cpu_pm_nb);
2210 }
2211 #else
hyp_cpu_pm_init(void)2212 static inline void __init hyp_cpu_pm_init(void)
2213 {
2214 }
hyp_cpu_pm_exit(void)2215 static inline void __init hyp_cpu_pm_exit(void)
2216 {
2217 }
2218 #endif
2219
init_cpu_logical_map(void)2220 static void __init init_cpu_logical_map(void)
2221 {
2222 unsigned int cpu;
2223
2224 /*
2225 * Copy the MPIDR <-> logical CPU ID mapping to hyp.
2226 * Only copy the set of online CPUs whose features have been checked
2227 * against the finalized system capabilities. The hypervisor will not
2228 * allow any other CPUs from the `possible` set to boot.
2229 */
2230 for_each_online_cpu(cpu)
2231 hyp_cpu_logical_map[cpu] = cpu_logical_map(cpu);
2232 }
2233
2234 #define init_psci_0_1_impl_state(config, what) \
2235 config.psci_0_1_ ## what ## _implemented = psci_ops.what
2236
init_psci_relay(void)2237 static bool __init init_psci_relay(void)
2238 {
2239 /*
2240 * If PSCI has not been initialized, protected KVM cannot install
2241 * itself on newly booted CPUs.
2242 */
2243 if (!psci_ops.get_version) {
2244 kvm_err("Cannot initialize protected mode without PSCI\n");
2245 return false;
2246 }
2247
2248 kvm_host_psci_config.version = psci_ops.get_version();
2249 kvm_host_psci_config.smccc_version = arm_smccc_get_version();
2250
2251 if (kvm_host_psci_config.version == PSCI_VERSION(0, 1)) {
2252 kvm_host_psci_config.function_ids_0_1 = get_psci_0_1_function_ids();
2253 init_psci_0_1_impl_state(kvm_host_psci_config, cpu_suspend);
2254 init_psci_0_1_impl_state(kvm_host_psci_config, cpu_on);
2255 init_psci_0_1_impl_state(kvm_host_psci_config, cpu_off);
2256 init_psci_0_1_impl_state(kvm_host_psci_config, migrate);
2257 }
2258 return true;
2259 }
2260
init_subsystems(void)2261 static int __init init_subsystems(void)
2262 {
2263 int err = 0;
2264
2265 /*
2266 * Enable hardware so that subsystem initialisation can access EL2.
2267 */
2268 on_each_cpu(cpu_hyp_init, NULL, 1);
2269
2270 /*
2271 * Register CPU lower-power notifier
2272 */
2273 hyp_cpu_pm_init();
2274
2275 /*
2276 * Init HYP view of VGIC
2277 */
2278 err = kvm_vgic_hyp_init();
2279 switch (err) {
2280 case 0:
2281 vgic_present = true;
2282 break;
2283 case -ENODEV:
2284 case -ENXIO:
2285 /*
2286 * No VGIC? No pKVM for you.
2287 *
2288 * Protected mode assumes that VGICv3 is present, so no point
2289 * in trying to hobble along if vgic initialization fails.
2290 */
2291 if (is_protected_kvm_enabled())
2292 goto out;
2293
2294 /*
2295 * Otherwise, userspace could choose to implement a GIC for its
2296 * guest on non-cooperative hardware.
2297 */
2298 vgic_present = false;
2299 err = 0;
2300 break;
2301 default:
2302 goto out;
2303 }
2304
2305 if (kvm_mode == KVM_MODE_NV &&
2306 !(vgic_present && kvm_vgic_global_state.type == VGIC_V3)) {
2307 kvm_err("NV support requires GICv3, giving up\n");
2308 err = -EINVAL;
2309 goto out;
2310 }
2311
2312 /*
2313 * Init HYP architected timer support
2314 */
2315 err = kvm_timer_hyp_init(vgic_present);
2316 if (err)
2317 goto out;
2318
2319 kvm_register_perf_callbacks(NULL);
2320
2321 out:
2322 if (err)
2323 hyp_cpu_pm_exit();
2324
2325 if (err || !is_protected_kvm_enabled())
2326 on_each_cpu(cpu_hyp_uninit, NULL, 1);
2327
2328 return err;
2329 }
2330
teardown_subsystems(void)2331 static void __init teardown_subsystems(void)
2332 {
2333 kvm_unregister_perf_callbacks();
2334 hyp_cpu_pm_exit();
2335 }
2336
teardown_hyp_mode(void)2337 static void __init teardown_hyp_mode(void)
2338 {
2339 bool free_sve = system_supports_sve() && is_protected_kvm_enabled();
2340 int cpu;
2341
2342 free_hyp_pgds();
2343 for_each_possible_cpu(cpu) {
2344 if (per_cpu(kvm_hyp_initialized, cpu))
2345 continue;
2346
2347 free_pages(per_cpu(kvm_arm_hyp_stack_base, cpu), NVHE_STACK_SHIFT - PAGE_SHIFT);
2348
2349 if (!kvm_nvhe_sym(kvm_arm_hyp_percpu_base)[cpu])
2350 continue;
2351
2352 if (free_sve) {
2353 struct cpu_sve_state *sve_state;
2354
2355 sve_state = per_cpu_ptr_nvhe_sym(kvm_host_data, cpu)->sve_state;
2356 free_pages((unsigned long) sve_state, pkvm_host_sve_state_order());
2357 }
2358
2359 free_pages(kvm_nvhe_sym(kvm_arm_hyp_percpu_base)[cpu], nvhe_percpu_order());
2360
2361 }
2362 }
2363
do_pkvm_init(u32 hyp_va_bits)2364 static int __init do_pkvm_init(u32 hyp_va_bits)
2365 {
2366 void *per_cpu_base = kvm_ksym_ref(kvm_nvhe_sym(kvm_arm_hyp_percpu_base));
2367 int ret;
2368
2369 preempt_disable();
2370 cpu_hyp_init_context();
2371 ret = kvm_call_hyp_nvhe(__pkvm_init, hyp_mem_base, hyp_mem_size,
2372 num_possible_cpus(), kern_hyp_va(per_cpu_base),
2373 hyp_va_bits);
2374 cpu_hyp_init_features();
2375
2376 /*
2377 * The stub hypercalls are now disabled, so set our local flag to
2378 * prevent a later re-init attempt in kvm_arch_enable_virtualization_cpu().
2379 */
2380 __this_cpu_write(kvm_hyp_initialized, 1);
2381 preempt_enable();
2382
2383 return ret;
2384 }
2385
get_hyp_id_aa64pfr0_el1(void)2386 static u64 get_hyp_id_aa64pfr0_el1(void)
2387 {
2388 /*
2389 * Track whether the system isn't affected by spectre/meltdown in the
2390 * hypervisor's view of id_aa64pfr0_el1, used for protected VMs.
2391 * Although this is per-CPU, we make it global for simplicity, e.g., not
2392 * to have to worry about vcpu migration.
2393 *
2394 * Unlike for non-protected VMs, userspace cannot override this for
2395 * protected VMs.
2396 */
2397 u64 val = read_sanitised_ftr_reg(SYS_ID_AA64PFR0_EL1);
2398
2399 val &= ~(ARM64_FEATURE_MASK(ID_AA64PFR0_EL1_CSV2) |
2400 ARM64_FEATURE_MASK(ID_AA64PFR0_EL1_CSV3));
2401
2402 val |= FIELD_PREP(ARM64_FEATURE_MASK(ID_AA64PFR0_EL1_CSV2),
2403 arm64_get_spectre_v2_state() == SPECTRE_UNAFFECTED);
2404 val |= FIELD_PREP(ARM64_FEATURE_MASK(ID_AA64PFR0_EL1_CSV3),
2405 arm64_get_meltdown_state() == SPECTRE_UNAFFECTED);
2406
2407 return val;
2408 }
2409
kvm_hyp_init_symbols(void)2410 static void kvm_hyp_init_symbols(void)
2411 {
2412 kvm_nvhe_sym(id_aa64pfr0_el1_sys_val) = get_hyp_id_aa64pfr0_el1();
2413 kvm_nvhe_sym(id_aa64pfr1_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64PFR1_EL1);
2414 kvm_nvhe_sym(id_aa64isar0_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64ISAR0_EL1);
2415 kvm_nvhe_sym(id_aa64isar1_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64ISAR1_EL1);
2416 kvm_nvhe_sym(id_aa64isar2_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64ISAR2_EL1);
2417 kvm_nvhe_sym(id_aa64mmfr0_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64MMFR0_EL1);
2418 kvm_nvhe_sym(id_aa64mmfr1_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64MMFR1_EL1);
2419 kvm_nvhe_sym(id_aa64mmfr2_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64MMFR2_EL1);
2420 kvm_nvhe_sym(id_aa64smfr0_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64SMFR0_EL1);
2421 kvm_nvhe_sym(__icache_flags) = __icache_flags;
2422 kvm_nvhe_sym(kvm_arm_vmid_bits) = kvm_arm_vmid_bits;
2423
2424 /* Propagate the FGT state to the the nVHE side */
2425 kvm_nvhe_sym(hfgrtr_masks) = hfgrtr_masks;
2426 kvm_nvhe_sym(hfgwtr_masks) = hfgwtr_masks;
2427 kvm_nvhe_sym(hfgitr_masks) = hfgitr_masks;
2428 kvm_nvhe_sym(hdfgrtr_masks) = hdfgrtr_masks;
2429 kvm_nvhe_sym(hdfgwtr_masks) = hdfgwtr_masks;
2430 kvm_nvhe_sym(hafgrtr_masks) = hafgrtr_masks;
2431 kvm_nvhe_sym(hfgrtr2_masks) = hfgrtr2_masks;
2432 kvm_nvhe_sym(hfgwtr2_masks) = hfgwtr2_masks;
2433 kvm_nvhe_sym(hfgitr2_masks) = hfgitr2_masks;
2434 kvm_nvhe_sym(hdfgrtr2_masks)= hdfgrtr2_masks;
2435 kvm_nvhe_sym(hdfgwtr2_masks)= hdfgwtr2_masks;
2436
2437 /*
2438 * Flush entire BSS since part of its data containing init symbols is read
2439 * while the MMU is off.
2440 */
2441 kvm_flush_dcache_to_poc(kvm_ksym_ref(__hyp_bss_start),
2442 kvm_ksym_ref(__hyp_bss_end) - kvm_ksym_ref(__hyp_bss_start));
2443 }
2444
kvm_hyp_init_protection(u32 hyp_va_bits)2445 static int __init kvm_hyp_init_protection(u32 hyp_va_bits)
2446 {
2447 void *addr = phys_to_virt(hyp_mem_base);
2448 int ret;
2449
2450 ret = create_hyp_mappings(addr, addr + hyp_mem_size, PAGE_HYP);
2451 if (ret)
2452 return ret;
2453
2454 ret = do_pkvm_init(hyp_va_bits);
2455 if (ret)
2456 return ret;
2457
2458 free_hyp_pgds();
2459
2460 return 0;
2461 }
2462
init_pkvm_host_sve_state(void)2463 static int init_pkvm_host_sve_state(void)
2464 {
2465 int cpu;
2466
2467 if (!system_supports_sve())
2468 return 0;
2469
2470 /* Allocate pages for host sve state in protected mode. */
2471 for_each_possible_cpu(cpu) {
2472 struct page *page = alloc_pages(GFP_KERNEL, pkvm_host_sve_state_order());
2473
2474 if (!page)
2475 return -ENOMEM;
2476
2477 per_cpu_ptr_nvhe_sym(kvm_host_data, cpu)->sve_state = page_address(page);
2478 }
2479
2480 /*
2481 * Don't map the pages in hyp since these are only used in protected
2482 * mode, which will (re)create its own mapping when initialized.
2483 */
2484
2485 return 0;
2486 }
2487
2488 /*
2489 * Finalizes the initialization of hyp mode, once everything else is initialized
2490 * and the initialziation process cannot fail.
2491 */
finalize_init_hyp_mode(void)2492 static void finalize_init_hyp_mode(void)
2493 {
2494 int cpu;
2495
2496 if (system_supports_sve() && is_protected_kvm_enabled()) {
2497 for_each_possible_cpu(cpu) {
2498 struct cpu_sve_state *sve_state;
2499
2500 sve_state = per_cpu_ptr_nvhe_sym(kvm_host_data, cpu)->sve_state;
2501 per_cpu_ptr_nvhe_sym(kvm_host_data, cpu)->sve_state =
2502 kern_hyp_va(sve_state);
2503 }
2504 }
2505 }
2506
pkvm_hyp_init_ptrauth(void)2507 static void pkvm_hyp_init_ptrauth(void)
2508 {
2509 struct kvm_cpu_context *hyp_ctxt;
2510 int cpu;
2511
2512 for_each_possible_cpu(cpu) {
2513 hyp_ctxt = per_cpu_ptr_nvhe_sym(kvm_hyp_ctxt, cpu);
2514 hyp_ctxt->sys_regs[APIAKEYLO_EL1] = get_random_long();
2515 hyp_ctxt->sys_regs[APIAKEYHI_EL1] = get_random_long();
2516 hyp_ctxt->sys_regs[APIBKEYLO_EL1] = get_random_long();
2517 hyp_ctxt->sys_regs[APIBKEYHI_EL1] = get_random_long();
2518 hyp_ctxt->sys_regs[APDAKEYLO_EL1] = get_random_long();
2519 hyp_ctxt->sys_regs[APDAKEYHI_EL1] = get_random_long();
2520 hyp_ctxt->sys_regs[APDBKEYLO_EL1] = get_random_long();
2521 hyp_ctxt->sys_regs[APDBKEYHI_EL1] = get_random_long();
2522 hyp_ctxt->sys_regs[APGAKEYLO_EL1] = get_random_long();
2523 hyp_ctxt->sys_regs[APGAKEYHI_EL1] = get_random_long();
2524 }
2525 }
2526
2527 /* Inits Hyp-mode on all online CPUs */
init_hyp_mode(void)2528 static int __init init_hyp_mode(void)
2529 {
2530 u32 hyp_va_bits;
2531 int cpu;
2532 int err = -ENOMEM;
2533
2534 /*
2535 * The protected Hyp-mode cannot be initialized if the memory pool
2536 * allocation has failed.
2537 */
2538 if (is_protected_kvm_enabled() && !hyp_mem_base)
2539 goto out_err;
2540
2541 /*
2542 * Allocate Hyp PGD and setup Hyp identity mapping
2543 */
2544 err = kvm_mmu_init(&hyp_va_bits);
2545 if (err)
2546 goto out_err;
2547
2548 /*
2549 * Allocate stack pages for Hypervisor-mode
2550 */
2551 for_each_possible_cpu(cpu) {
2552 unsigned long stack_base;
2553
2554 stack_base = __get_free_pages(GFP_KERNEL, NVHE_STACK_SHIFT - PAGE_SHIFT);
2555 if (!stack_base) {
2556 err = -ENOMEM;
2557 goto out_err;
2558 }
2559
2560 per_cpu(kvm_arm_hyp_stack_base, cpu) = stack_base;
2561 }
2562
2563 /*
2564 * Allocate and initialize pages for Hypervisor-mode percpu regions.
2565 */
2566 for_each_possible_cpu(cpu) {
2567 struct page *page;
2568 void *page_addr;
2569
2570 page = alloc_pages(GFP_KERNEL, nvhe_percpu_order());
2571 if (!page) {
2572 err = -ENOMEM;
2573 goto out_err;
2574 }
2575
2576 page_addr = page_address(page);
2577 memcpy(page_addr, CHOOSE_NVHE_SYM(__per_cpu_start), nvhe_percpu_size());
2578 kvm_nvhe_sym(kvm_arm_hyp_percpu_base)[cpu] = (unsigned long)page_addr;
2579 }
2580
2581 /*
2582 * Map the Hyp-code called directly from the host
2583 */
2584 err = create_hyp_mappings(kvm_ksym_ref(__hyp_text_start),
2585 kvm_ksym_ref(__hyp_text_end), PAGE_HYP_EXEC);
2586 if (err) {
2587 kvm_err("Cannot map world-switch code\n");
2588 goto out_err;
2589 }
2590
2591 err = create_hyp_mappings(kvm_ksym_ref(__hyp_data_start),
2592 kvm_ksym_ref(__hyp_data_end), PAGE_HYP);
2593 if (err) {
2594 kvm_err("Cannot map .hyp.data section\n");
2595 goto out_err;
2596 }
2597
2598 err = create_hyp_mappings(kvm_ksym_ref(__hyp_rodata_start),
2599 kvm_ksym_ref(__hyp_rodata_end), PAGE_HYP_RO);
2600 if (err) {
2601 kvm_err("Cannot map .hyp.rodata section\n");
2602 goto out_err;
2603 }
2604
2605 err = create_hyp_mappings(kvm_ksym_ref(__start_rodata),
2606 kvm_ksym_ref(__end_rodata), PAGE_HYP_RO);
2607 if (err) {
2608 kvm_err("Cannot map rodata section\n");
2609 goto out_err;
2610 }
2611
2612 /*
2613 * .hyp.bss is guaranteed to be placed at the beginning of the .bss
2614 * section thanks to an assertion in the linker script. Map it RW and
2615 * the rest of .bss RO.
2616 */
2617 err = create_hyp_mappings(kvm_ksym_ref(__hyp_bss_start),
2618 kvm_ksym_ref(__hyp_bss_end), PAGE_HYP);
2619 if (err) {
2620 kvm_err("Cannot map hyp bss section: %d\n", err);
2621 goto out_err;
2622 }
2623
2624 err = create_hyp_mappings(kvm_ksym_ref(__hyp_bss_end),
2625 kvm_ksym_ref(__bss_stop), PAGE_HYP_RO);
2626 if (err) {
2627 kvm_err("Cannot map bss section\n");
2628 goto out_err;
2629 }
2630
2631 /*
2632 * Map the Hyp stack pages
2633 */
2634 for_each_possible_cpu(cpu) {
2635 struct kvm_nvhe_init_params *params = per_cpu_ptr_nvhe_sym(kvm_init_params, cpu);
2636 char *stack_base = (char *)per_cpu(kvm_arm_hyp_stack_base, cpu);
2637
2638 err = create_hyp_stack(__pa(stack_base), ¶ms->stack_hyp_va);
2639 if (err) {
2640 kvm_err("Cannot map hyp stack\n");
2641 goto out_err;
2642 }
2643
2644 /*
2645 * Save the stack PA in nvhe_init_params. This will be needed
2646 * to recreate the stack mapping in protected nVHE mode.
2647 * __hyp_pa() won't do the right thing there, since the stack
2648 * has been mapped in the flexible private VA space.
2649 */
2650 params->stack_pa = __pa(stack_base);
2651 }
2652
2653 for_each_possible_cpu(cpu) {
2654 char *percpu_begin = (char *)kvm_nvhe_sym(kvm_arm_hyp_percpu_base)[cpu];
2655 char *percpu_end = percpu_begin + nvhe_percpu_size();
2656
2657 /* Map Hyp percpu pages */
2658 err = create_hyp_mappings(percpu_begin, percpu_end, PAGE_HYP);
2659 if (err) {
2660 kvm_err("Cannot map hyp percpu region\n");
2661 goto out_err;
2662 }
2663
2664 /* Prepare the CPU initialization parameters */
2665 cpu_prepare_hyp_mode(cpu, hyp_va_bits);
2666 }
2667
2668 kvm_hyp_init_symbols();
2669
2670 if (is_protected_kvm_enabled()) {
2671 if (IS_ENABLED(CONFIG_ARM64_PTR_AUTH_KERNEL) &&
2672 cpus_have_final_cap(ARM64_HAS_ADDRESS_AUTH))
2673 pkvm_hyp_init_ptrauth();
2674
2675 init_cpu_logical_map();
2676
2677 if (!init_psci_relay()) {
2678 err = -ENODEV;
2679 goto out_err;
2680 }
2681
2682 err = init_pkvm_host_sve_state();
2683 if (err)
2684 goto out_err;
2685
2686 err = kvm_hyp_init_protection(hyp_va_bits);
2687 if (err) {
2688 kvm_err("Failed to init hyp memory protection\n");
2689 goto out_err;
2690 }
2691 }
2692
2693 return 0;
2694
2695 out_err:
2696 teardown_hyp_mode();
2697 kvm_err("error initializing Hyp mode: %d\n", err);
2698 return err;
2699 }
2700
kvm_mpidr_to_vcpu(struct kvm * kvm,unsigned long mpidr)2701 struct kvm_vcpu *kvm_mpidr_to_vcpu(struct kvm *kvm, unsigned long mpidr)
2702 {
2703 struct kvm_vcpu *vcpu = NULL;
2704 struct kvm_mpidr_data *data;
2705 unsigned long i;
2706
2707 mpidr &= MPIDR_HWID_BITMASK;
2708
2709 rcu_read_lock();
2710 data = rcu_dereference(kvm->arch.mpidr_data);
2711
2712 if (data) {
2713 u16 idx = kvm_mpidr_index(data, mpidr);
2714
2715 vcpu = kvm_get_vcpu(kvm, data->cmpidr_to_idx[idx]);
2716 if (mpidr != kvm_vcpu_get_mpidr_aff(vcpu))
2717 vcpu = NULL;
2718 }
2719
2720 rcu_read_unlock();
2721
2722 if (vcpu)
2723 return vcpu;
2724
2725 kvm_for_each_vcpu(i, vcpu, kvm) {
2726 if (mpidr == kvm_vcpu_get_mpidr_aff(vcpu))
2727 return vcpu;
2728 }
2729 return NULL;
2730 }
2731
kvm_arch_irqchip_in_kernel(struct kvm * kvm)2732 bool kvm_arch_irqchip_in_kernel(struct kvm *kvm)
2733 {
2734 return irqchip_in_kernel(kvm);
2735 }
2736
kvm_arch_irq_bypass_add_producer(struct irq_bypass_consumer * cons,struct irq_bypass_producer * prod)2737 int kvm_arch_irq_bypass_add_producer(struct irq_bypass_consumer *cons,
2738 struct irq_bypass_producer *prod)
2739 {
2740 struct kvm_kernel_irqfd *irqfd =
2741 container_of(cons, struct kvm_kernel_irqfd, consumer);
2742 struct kvm_kernel_irq_routing_entry *irq_entry = &irqfd->irq_entry;
2743
2744 /*
2745 * The only thing we have a chance of directly-injecting is LPIs. Maybe
2746 * one day...
2747 */
2748 if (irq_entry->type != KVM_IRQ_ROUTING_MSI)
2749 return 0;
2750
2751 return kvm_vgic_v4_set_forwarding(irqfd->kvm, prod->irq,
2752 &irqfd->irq_entry);
2753 }
2754
kvm_arch_irq_bypass_del_producer(struct irq_bypass_consumer * cons,struct irq_bypass_producer * prod)2755 void kvm_arch_irq_bypass_del_producer(struct irq_bypass_consumer *cons,
2756 struct irq_bypass_producer *prod)
2757 {
2758 struct kvm_kernel_irqfd *irqfd =
2759 container_of(cons, struct kvm_kernel_irqfd, consumer);
2760 struct kvm_kernel_irq_routing_entry *irq_entry = &irqfd->irq_entry;
2761
2762 if (irq_entry->type != KVM_IRQ_ROUTING_MSI)
2763 return;
2764
2765 kvm_vgic_v4_unset_forwarding(irqfd->kvm, prod->irq);
2766 }
2767
kvm_arch_irqfd_route_changed(struct kvm_kernel_irq_routing_entry * old,struct kvm_kernel_irq_routing_entry * new)2768 bool kvm_arch_irqfd_route_changed(struct kvm_kernel_irq_routing_entry *old,
2769 struct kvm_kernel_irq_routing_entry *new)
2770 {
2771 if (old->type != KVM_IRQ_ROUTING_MSI ||
2772 new->type != KVM_IRQ_ROUTING_MSI)
2773 return true;
2774
2775 return memcmp(&old->msi, &new->msi, sizeof(new->msi));
2776 }
2777
kvm_arch_update_irqfd_routing(struct kvm * kvm,unsigned int host_irq,uint32_t guest_irq,bool set)2778 int kvm_arch_update_irqfd_routing(struct kvm *kvm, unsigned int host_irq,
2779 uint32_t guest_irq, bool set)
2780 {
2781 /*
2782 * Remapping the vLPI requires taking the its_lock mutex to resolve
2783 * the new translation. We're in spinlock land at this point, so no
2784 * chance of resolving the translation.
2785 *
2786 * Unmap the vLPI and fall back to software LPI injection.
2787 */
2788 return kvm_vgic_v4_unset_forwarding(kvm, host_irq);
2789 }
2790
kvm_arch_irq_bypass_stop(struct irq_bypass_consumer * cons)2791 void kvm_arch_irq_bypass_stop(struct irq_bypass_consumer *cons)
2792 {
2793 struct kvm_kernel_irqfd *irqfd =
2794 container_of(cons, struct kvm_kernel_irqfd, consumer);
2795
2796 kvm_arm_halt_guest(irqfd->kvm);
2797 }
2798
kvm_arch_irq_bypass_start(struct irq_bypass_consumer * cons)2799 void kvm_arch_irq_bypass_start(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_resume_guest(irqfd->kvm);
2805 }
2806
2807 /* Initialize Hyp-mode and memory mappings on all CPUs */
kvm_arm_init(void)2808 static __init int kvm_arm_init(void)
2809 {
2810 int err;
2811 bool in_hyp_mode;
2812
2813 if (!is_hyp_mode_available()) {
2814 kvm_info("HYP mode not available\n");
2815 return -ENODEV;
2816 }
2817
2818 if (kvm_get_mode() == KVM_MODE_NONE) {
2819 kvm_info("KVM disabled from command line\n");
2820 return -ENODEV;
2821 }
2822
2823 err = kvm_sys_reg_table_init();
2824 if (err) {
2825 kvm_info("Error initializing system register tables");
2826 return err;
2827 }
2828
2829 in_hyp_mode = is_kernel_in_hyp_mode();
2830
2831 if (cpus_have_final_cap(ARM64_WORKAROUND_DEVICE_LOAD_ACQUIRE) ||
2832 cpus_have_final_cap(ARM64_WORKAROUND_1508412))
2833 kvm_info("Guests without required CPU erratum workarounds can deadlock system!\n" \
2834 "Only trusted guests should be used on this system.\n");
2835
2836 err = kvm_set_ipa_limit();
2837 if (err)
2838 return err;
2839
2840 err = kvm_arm_init_sve();
2841 if (err)
2842 return err;
2843
2844 err = kvm_arm_vmid_alloc_init();
2845 if (err) {
2846 kvm_err("Failed to initialize VMID allocator.\n");
2847 return err;
2848 }
2849
2850 if (!in_hyp_mode) {
2851 err = init_hyp_mode();
2852 if (err)
2853 goto out_err;
2854 }
2855
2856 err = kvm_init_vector_slots();
2857 if (err) {
2858 kvm_err("Cannot initialise vector slots\n");
2859 goto out_hyp;
2860 }
2861
2862 err = init_subsystems();
2863 if (err)
2864 goto out_hyp;
2865
2866 kvm_info("%s%sVHE%s mode initialized successfully\n",
2867 in_hyp_mode ? "" : (is_protected_kvm_enabled() ?
2868 "Protected " : "Hyp "),
2869 in_hyp_mode ? "" : (cpus_have_final_cap(ARM64_KVM_HVHE) ?
2870 "h" : "n"),
2871 cpus_have_final_cap(ARM64_HAS_NESTED_VIRT) ? "+NV2": "");
2872
2873 /*
2874 * FIXME: Do something reasonable if kvm_init() fails after pKVM
2875 * hypervisor protection is finalized.
2876 */
2877 err = kvm_init(sizeof(struct kvm_vcpu), 0, THIS_MODULE);
2878 if (err)
2879 goto out_subs;
2880
2881 /*
2882 * This should be called after initialization is done and failure isn't
2883 * possible anymore.
2884 */
2885 if (!in_hyp_mode)
2886 finalize_init_hyp_mode();
2887
2888 kvm_arm_initialised = true;
2889
2890 return 0;
2891
2892 out_subs:
2893 teardown_subsystems();
2894 out_hyp:
2895 if (!in_hyp_mode)
2896 teardown_hyp_mode();
2897 out_err:
2898 kvm_arm_vmid_alloc_free();
2899 return err;
2900 }
2901
early_kvm_mode_cfg(char * arg)2902 static int __init early_kvm_mode_cfg(char *arg)
2903 {
2904 if (!arg)
2905 return -EINVAL;
2906
2907 if (strcmp(arg, "none") == 0) {
2908 kvm_mode = KVM_MODE_NONE;
2909 return 0;
2910 }
2911
2912 if (!is_hyp_mode_available()) {
2913 pr_warn_once("KVM is not available. Ignoring kvm-arm.mode\n");
2914 return 0;
2915 }
2916
2917 if (strcmp(arg, "protected") == 0) {
2918 if (!is_kernel_in_hyp_mode())
2919 kvm_mode = KVM_MODE_PROTECTED;
2920 else
2921 pr_warn_once("Protected KVM not available with VHE\n");
2922
2923 return 0;
2924 }
2925
2926 if (strcmp(arg, "nvhe") == 0 && !WARN_ON(is_kernel_in_hyp_mode())) {
2927 kvm_mode = KVM_MODE_DEFAULT;
2928 return 0;
2929 }
2930
2931 if (strcmp(arg, "nested") == 0 && !WARN_ON(!is_kernel_in_hyp_mode())) {
2932 kvm_mode = KVM_MODE_NV;
2933 return 0;
2934 }
2935
2936 return -EINVAL;
2937 }
2938 early_param("kvm-arm.mode", early_kvm_mode_cfg);
2939
early_kvm_wfx_trap_policy_cfg(char * arg,enum kvm_wfx_trap_policy * p)2940 static int __init early_kvm_wfx_trap_policy_cfg(char *arg, enum kvm_wfx_trap_policy *p)
2941 {
2942 if (!arg)
2943 return -EINVAL;
2944
2945 if (strcmp(arg, "trap") == 0) {
2946 *p = KVM_WFX_TRAP;
2947 return 0;
2948 }
2949
2950 if (strcmp(arg, "notrap") == 0) {
2951 *p = KVM_WFX_NOTRAP;
2952 return 0;
2953 }
2954
2955 return -EINVAL;
2956 }
2957
early_kvm_wfi_trap_policy_cfg(char * arg)2958 static int __init early_kvm_wfi_trap_policy_cfg(char *arg)
2959 {
2960 return early_kvm_wfx_trap_policy_cfg(arg, &kvm_wfi_trap_policy);
2961 }
2962 early_param("kvm-arm.wfi_trap_policy", early_kvm_wfi_trap_policy_cfg);
2963
early_kvm_wfe_trap_policy_cfg(char * arg)2964 static int __init early_kvm_wfe_trap_policy_cfg(char *arg)
2965 {
2966 return early_kvm_wfx_trap_policy_cfg(arg, &kvm_wfe_trap_policy);
2967 }
2968 early_param("kvm-arm.wfe_trap_policy", early_kvm_wfe_trap_policy_cfg);
2969
kvm_get_mode(void)2970 enum kvm_mode kvm_get_mode(void)
2971 {
2972 return kvm_mode;
2973 }
2974
2975 module_init(kvm_arm_init);
2976