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/errno.h>
10 #include <linux/err.h>
11 #include <linux/kvm_host.h>
12 #include <linux/list.h>
13 #include <linux/module.h>
14 #include <linux/vmalloc.h>
15 #include <linux/fs.h>
16 #include <linux/mman.h>
17 #include <linux/sched.h>
18 #include <linux/kvm.h>
19 #include <linux/kvm_irqfd.h>
20 #include <linux/irqbypass.h>
21 #include <linux/sched/stat.h>
22 #include <linux/psci.h>
23 #include <trace/events/kvm.h>
24
25 #define CREATE_TRACE_POINTS
26 #include "trace_arm.h"
27
28 #include <linux/uaccess.h>
29 #include <asm/ptrace.h>
30 #include <asm/mman.h>
31 #include <asm/tlbflush.h>
32 #include <asm/cacheflush.h>
33 #include <asm/cpufeature.h>
34 #include <asm/virt.h>
35 #include <asm/kvm_arm.h>
36 #include <asm/kvm_asm.h>
37 #include <asm/kvm_emulate.h>
38 #include <asm/kvm_mmu.h>
39 #include <asm/kvm_nested.h>
40 #include <asm/kvm_pkvm.h>
41 #include <asm/kvm_ptrauth.h>
42 #include <asm/sections.h>
43
44 #include <kvm/arm_hypercalls.h>
45 #include <kvm/arm_pmu.h>
46 #include <kvm/arm_psci.h>
47
48 #include "sys_regs.h"
49
50 static enum kvm_mode kvm_mode = KVM_MODE_DEFAULT;
51
52 enum kvm_wfx_trap_policy {
53 KVM_WFX_NOTRAP_SINGLE_TASK, /* Default option */
54 KVM_WFX_NOTRAP,
55 KVM_WFX_TRAP,
56 };
57
58 static enum kvm_wfx_trap_policy kvm_wfi_trap_policy __read_mostly = KVM_WFX_NOTRAP_SINGLE_TASK;
59 static enum kvm_wfx_trap_policy kvm_wfe_trap_policy __read_mostly = KVM_WFX_NOTRAP_SINGLE_TASK;
60
61 DECLARE_KVM_HYP_PER_CPU(unsigned long, kvm_hyp_vector);
62
63 DEFINE_PER_CPU(unsigned long, kvm_arm_hyp_stack_base);
64 DECLARE_KVM_NVHE_PER_CPU(struct kvm_nvhe_init_params, kvm_init_params);
65
66 DECLARE_KVM_NVHE_PER_CPU(struct kvm_cpu_context, kvm_hyp_ctxt);
67
68 static bool vgic_present, kvm_arm_initialised;
69
70 static DEFINE_PER_CPU(unsigned char, kvm_hyp_initialized);
71
is_kvm_arm_initialised(void)72 bool is_kvm_arm_initialised(void)
73 {
74 return kvm_arm_initialised;
75 }
76
kvm_arch_vcpu_should_kick(struct kvm_vcpu * vcpu)77 int kvm_arch_vcpu_should_kick(struct kvm_vcpu *vcpu)
78 {
79 return kvm_vcpu_exiting_guest_mode(vcpu) == IN_GUEST_MODE;
80 }
81
kvm_vm_ioctl_enable_cap(struct kvm * kvm,struct kvm_enable_cap * cap)82 int kvm_vm_ioctl_enable_cap(struct kvm *kvm,
83 struct kvm_enable_cap *cap)
84 {
85 int r = -EINVAL;
86
87 if (cap->flags)
88 return -EINVAL;
89
90 if (kvm_vm_is_protected(kvm) && !kvm_pvm_ext_allowed(cap->cap))
91 return -EINVAL;
92
93 switch (cap->cap) {
94 case KVM_CAP_ARM_NISV_TO_USER:
95 r = 0;
96 set_bit(KVM_ARCH_FLAG_RETURN_NISV_IO_ABORT_TO_USER,
97 &kvm->arch.flags);
98 break;
99 case KVM_CAP_ARM_MTE:
100 mutex_lock(&kvm->lock);
101 if (system_supports_mte() && !kvm->created_vcpus) {
102 r = 0;
103 set_bit(KVM_ARCH_FLAG_MTE_ENABLED, &kvm->arch.flags);
104 }
105 mutex_unlock(&kvm->lock);
106 break;
107 case KVM_CAP_ARM_SYSTEM_SUSPEND:
108 r = 0;
109 set_bit(KVM_ARCH_FLAG_SYSTEM_SUSPEND_ENABLED, &kvm->arch.flags);
110 break;
111 case KVM_CAP_ARM_EAGER_SPLIT_CHUNK_SIZE:
112 mutex_lock(&kvm->slots_lock);
113 /*
114 * To keep things simple, allow changing the chunk
115 * size only when no memory slots have been created.
116 */
117 if (kvm_are_all_memslots_empty(kvm)) {
118 u64 new_cap = cap->args[0];
119
120 if (!new_cap || kvm_is_block_size_supported(new_cap)) {
121 r = 0;
122 kvm->arch.mmu.split_page_chunk_size = new_cap;
123 }
124 }
125 mutex_unlock(&kvm->slots_lock);
126 break;
127 case KVM_CAP_ARM_WRITABLE_IMP_ID_REGS:
128 mutex_lock(&kvm->lock);
129 if (!kvm->created_vcpus) {
130 r = 0;
131 set_bit(KVM_ARCH_FLAG_WRITABLE_IMP_ID_REGS, &kvm->arch.flags);
132 }
133 mutex_unlock(&kvm->lock);
134 break;
135 default:
136 break;
137 }
138
139 return r;
140 }
141
kvm_arm_default_max_vcpus(void)142 static int kvm_arm_default_max_vcpus(void)
143 {
144 return vgic_present ? kvm_vgic_get_max_vcpus() : KVM_MAX_VCPUS;
145 }
146
147 /**
148 * kvm_arch_init_vm - initializes a VM data structure
149 * @kvm: pointer to the KVM struct
150 * @type: kvm device type
151 */
kvm_arch_init_vm(struct kvm * kvm,unsigned long type)152 int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
153 {
154 int ret;
155
156 mutex_init(&kvm->arch.config_lock);
157
158 #ifdef CONFIG_LOCKDEP
159 /* Clue in lockdep that the config_lock must be taken inside kvm->lock */
160 mutex_lock(&kvm->lock);
161 mutex_lock(&kvm->arch.config_lock);
162 mutex_unlock(&kvm->arch.config_lock);
163 mutex_unlock(&kvm->lock);
164 #endif
165
166 kvm_init_nested(kvm);
167
168 ret = kvm_share_hyp(kvm, kvm + 1);
169 if (ret)
170 return ret;
171
172 if (!zalloc_cpumask_var(&kvm->arch.supported_cpus, GFP_KERNEL_ACCOUNT)) {
173 ret = -ENOMEM;
174 goto err_unshare_kvm;
175 }
176 cpumask_copy(kvm->arch.supported_cpus, cpu_possible_mask);
177
178 ret = kvm_init_stage2_mmu(kvm, &kvm->arch.mmu, type);
179 if (ret)
180 goto err_free_cpumask;
181
182 if (is_protected_kvm_enabled()) {
183 /*
184 * If any failures occur after this is successful, make sure to
185 * call __pkvm_unreserve_vm to unreserve the VM in hyp.
186 */
187 ret = pkvm_init_host_vm(kvm);
188 if (ret)
189 goto err_free_cpumask;
190 }
191
192 kvm_vgic_early_init(kvm);
193
194 kvm_timer_init_vm(kvm);
195
196 /* The maximum number of VCPUs is limited by the host's GIC model */
197 kvm->max_vcpus = kvm_arm_default_max_vcpus();
198
199 kvm_arm_init_hypercalls(kvm);
200
201 bitmap_zero(kvm->arch.vcpu_features, KVM_VCPU_MAX_FEATURES);
202
203 return 0;
204
205 err_free_cpumask:
206 free_cpumask_var(kvm->arch.supported_cpus);
207 err_unshare_kvm:
208 kvm_unshare_hyp(kvm, kvm + 1);
209 return ret;
210 }
211
kvm_arch_vcpu_fault(struct kvm_vcpu * vcpu,struct vm_fault * vmf)212 vm_fault_t kvm_arch_vcpu_fault(struct kvm_vcpu *vcpu, struct vm_fault *vmf)
213 {
214 return VM_FAULT_SIGBUS;
215 }
216
kvm_arch_create_vm_debugfs(struct kvm * kvm)217 void kvm_arch_create_vm_debugfs(struct kvm *kvm)
218 {
219 kvm_sys_regs_create_debugfs(kvm);
220 kvm_s2_ptdump_create_debugfs(kvm);
221 }
222
kvm_destroy_mpidr_data(struct kvm * kvm)223 static void kvm_destroy_mpidr_data(struct kvm *kvm)
224 {
225 struct kvm_mpidr_data *data;
226
227 mutex_lock(&kvm->arch.config_lock);
228
229 data = rcu_dereference_protected(kvm->arch.mpidr_data,
230 lockdep_is_held(&kvm->arch.config_lock));
231 if (data) {
232 rcu_assign_pointer(kvm->arch.mpidr_data, NULL);
233 synchronize_rcu();
234 kfree(data);
235 }
236
237 mutex_unlock(&kvm->arch.config_lock);
238 }
239
240 /**
241 * kvm_arch_destroy_vm - destroy the VM data structure
242 * @kvm: pointer to the KVM struct
243 */
kvm_arch_destroy_vm(struct kvm * kvm)244 void kvm_arch_destroy_vm(struct kvm *kvm)
245 {
246 bitmap_free(kvm->arch.pmu_filter);
247 free_cpumask_var(kvm->arch.supported_cpus);
248
249 kvm_vgic_destroy(kvm);
250
251 if (is_protected_kvm_enabled())
252 pkvm_destroy_hyp_vm(kvm);
253
254 kvm_destroy_mpidr_data(kvm);
255
256 kfree(kvm->arch.sysreg_masks);
257 kvm_destroy_vcpus(kvm);
258
259 kvm_unshare_hyp(kvm, kvm + 1);
260
261 kvm_arm_teardown_hypercalls(kvm);
262 }
263
kvm_has_full_ptr_auth(void)264 static bool kvm_has_full_ptr_auth(void)
265 {
266 bool apa, gpa, api, gpi, apa3, gpa3;
267 u64 isar1, isar2, val;
268
269 /*
270 * Check that:
271 *
272 * - both Address and Generic auth are implemented for a given
273 * algorithm (Q5, IMPDEF or Q3)
274 * - only a single algorithm is implemented.
275 */
276 if (!system_has_full_ptr_auth())
277 return false;
278
279 isar1 = read_sanitised_ftr_reg(SYS_ID_AA64ISAR1_EL1);
280 isar2 = read_sanitised_ftr_reg(SYS_ID_AA64ISAR2_EL1);
281
282 apa = !!FIELD_GET(ID_AA64ISAR1_EL1_APA_MASK, isar1);
283 val = FIELD_GET(ID_AA64ISAR1_EL1_GPA_MASK, isar1);
284 gpa = (val == ID_AA64ISAR1_EL1_GPA_IMP);
285
286 api = !!FIELD_GET(ID_AA64ISAR1_EL1_API_MASK, isar1);
287 val = FIELD_GET(ID_AA64ISAR1_EL1_GPI_MASK, isar1);
288 gpi = (val == ID_AA64ISAR1_EL1_GPI_IMP);
289
290 apa3 = !!FIELD_GET(ID_AA64ISAR2_EL1_APA3_MASK, isar2);
291 val = FIELD_GET(ID_AA64ISAR2_EL1_GPA3_MASK, isar2);
292 gpa3 = (val == ID_AA64ISAR2_EL1_GPA3_IMP);
293
294 return (apa == gpa && api == gpi && apa3 == gpa3 &&
295 (apa + api + apa3) == 1);
296 }
297
kvm_vm_ioctl_check_extension(struct kvm * kvm,long ext)298 int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
299 {
300 int r;
301
302 if (kvm && kvm_vm_is_protected(kvm) && !kvm_pvm_ext_allowed(ext))
303 return 0;
304
305 switch (ext) {
306 case KVM_CAP_IRQCHIP:
307 r = vgic_present;
308 break;
309 case KVM_CAP_IOEVENTFD:
310 case KVM_CAP_USER_MEMORY:
311 case KVM_CAP_SYNC_MMU:
312 case KVM_CAP_DESTROY_MEMORY_REGION_WORKS:
313 case KVM_CAP_ONE_REG:
314 case KVM_CAP_ARM_PSCI:
315 case KVM_CAP_ARM_PSCI_0_2:
316 case KVM_CAP_READONLY_MEM:
317 case KVM_CAP_MP_STATE:
318 case KVM_CAP_IMMEDIATE_EXIT:
319 case KVM_CAP_VCPU_EVENTS:
320 case KVM_CAP_ARM_IRQ_LINE_LAYOUT_2:
321 case KVM_CAP_ARM_NISV_TO_USER:
322 case KVM_CAP_ARM_INJECT_EXT_DABT:
323 case KVM_CAP_SET_GUEST_DEBUG:
324 case KVM_CAP_VCPU_ATTRIBUTES:
325 case KVM_CAP_PTP_KVM:
326 case KVM_CAP_ARM_SYSTEM_SUSPEND:
327 case KVM_CAP_IRQFD_RESAMPLE:
328 case KVM_CAP_COUNTER_OFFSET:
329 case KVM_CAP_ARM_WRITABLE_IMP_ID_REGS:
330 r = 1;
331 break;
332 case KVM_CAP_SET_GUEST_DEBUG2:
333 return KVM_GUESTDBG_VALID_MASK;
334 case KVM_CAP_ARM_SET_DEVICE_ADDR:
335 r = 1;
336 break;
337 case KVM_CAP_NR_VCPUS:
338 /*
339 * ARM64 treats KVM_CAP_NR_CPUS differently from all other
340 * architectures, as it does not always bound it to
341 * KVM_CAP_MAX_VCPUS. It should not matter much because
342 * this is just an advisory value.
343 */
344 r = min_t(unsigned int, num_online_cpus(),
345 kvm_arm_default_max_vcpus());
346 break;
347 case KVM_CAP_MAX_VCPUS:
348 case KVM_CAP_MAX_VCPU_ID:
349 if (kvm)
350 r = kvm->max_vcpus;
351 else
352 r = kvm_arm_default_max_vcpus();
353 break;
354 case KVM_CAP_MSI_DEVID:
355 if (!kvm)
356 r = -EINVAL;
357 else
358 r = kvm->arch.vgic.msis_require_devid;
359 break;
360 case KVM_CAP_ARM_USER_IRQ:
361 /*
362 * 1: EL1_VTIMER, EL1_PTIMER, and PMU.
363 * (bump this number if adding more devices)
364 */
365 r = 1;
366 break;
367 case KVM_CAP_ARM_MTE:
368 r = system_supports_mte();
369 break;
370 case KVM_CAP_STEAL_TIME:
371 r = kvm_arm_pvtime_supported();
372 break;
373 case KVM_CAP_ARM_EL1_32BIT:
374 r = cpus_have_final_cap(ARM64_HAS_32BIT_EL1);
375 break;
376 case KVM_CAP_ARM_EL2:
377 r = cpus_have_final_cap(ARM64_HAS_NESTED_VIRT);
378 break;
379 case KVM_CAP_ARM_EL2_E2H0:
380 r = cpus_have_final_cap(ARM64_HAS_HCR_NV1);
381 break;
382 case KVM_CAP_GUEST_DEBUG_HW_BPS:
383 r = get_num_brps();
384 break;
385 case KVM_CAP_GUEST_DEBUG_HW_WPS:
386 r = get_num_wrps();
387 break;
388 case KVM_CAP_ARM_PMU_V3:
389 r = kvm_supports_guest_pmuv3();
390 break;
391 case KVM_CAP_ARM_INJECT_SERROR_ESR:
392 r = cpus_have_final_cap(ARM64_HAS_RAS_EXTN);
393 break;
394 case KVM_CAP_ARM_VM_IPA_SIZE:
395 r = get_kvm_ipa_limit();
396 break;
397 case KVM_CAP_ARM_SVE:
398 r = system_supports_sve();
399 break;
400 case KVM_CAP_ARM_PTRAUTH_ADDRESS:
401 case KVM_CAP_ARM_PTRAUTH_GENERIC:
402 r = kvm_has_full_ptr_auth();
403 break;
404 case KVM_CAP_ARM_EAGER_SPLIT_CHUNK_SIZE:
405 if (kvm)
406 r = kvm->arch.mmu.split_page_chunk_size;
407 else
408 r = KVM_ARM_EAGER_SPLIT_CHUNK_SIZE_DEFAULT;
409 break;
410 case KVM_CAP_ARM_SUPPORTED_BLOCK_SIZES:
411 r = kvm_supported_block_sizes();
412 break;
413 case KVM_CAP_ARM_SUPPORTED_REG_MASK_RANGES:
414 r = BIT(0);
415 break;
416 case KVM_CAP_ARM_CACHEABLE_PFNMAP_SUPPORTED:
417 if (!kvm)
418 r = -EINVAL;
419 else
420 r = kvm_supports_cacheable_pfnmap();
421 break;
422
423 default:
424 r = 0;
425 }
426
427 return r;
428 }
429
kvm_arch_dev_ioctl(struct file * filp,unsigned int ioctl,unsigned long arg)430 long kvm_arch_dev_ioctl(struct file *filp,
431 unsigned int ioctl, unsigned long arg)
432 {
433 return -EINVAL;
434 }
435
kvm_arch_alloc_vm(void)436 struct kvm *kvm_arch_alloc_vm(void)
437 {
438 size_t sz = sizeof(struct kvm);
439
440 if (!has_vhe())
441 return kzalloc(sz, GFP_KERNEL_ACCOUNT);
442
443 return __vmalloc(sz, GFP_KERNEL_ACCOUNT | __GFP_HIGHMEM | __GFP_ZERO);
444 }
445
kvm_arch_vcpu_precreate(struct kvm * kvm,unsigned int id)446 int kvm_arch_vcpu_precreate(struct kvm *kvm, unsigned int id)
447 {
448 if (irqchip_in_kernel(kvm) && vgic_initialized(kvm))
449 return -EBUSY;
450
451 if (id >= kvm->max_vcpus)
452 return -EINVAL;
453
454 return 0;
455 }
456
kvm_arch_vcpu_create(struct kvm_vcpu * vcpu)457 int kvm_arch_vcpu_create(struct kvm_vcpu *vcpu)
458 {
459 int err;
460
461 spin_lock_init(&vcpu->arch.mp_state_lock);
462
463 #ifdef CONFIG_LOCKDEP
464 /* Inform lockdep that the config_lock is acquired after vcpu->mutex */
465 mutex_lock(&vcpu->mutex);
466 mutex_lock(&vcpu->kvm->arch.config_lock);
467 mutex_unlock(&vcpu->kvm->arch.config_lock);
468 mutex_unlock(&vcpu->mutex);
469 #endif
470
471 /* Force users to call KVM_ARM_VCPU_INIT */
472 vcpu_clear_flag(vcpu, VCPU_INITIALIZED);
473
474 vcpu->arch.mmu_page_cache.gfp_zero = __GFP_ZERO;
475
476 /* Set up the timer */
477 kvm_timer_vcpu_init(vcpu);
478
479 kvm_pmu_vcpu_init(vcpu);
480
481 kvm_arm_pvtime_vcpu_init(&vcpu->arch);
482
483 vcpu->arch.hw_mmu = &vcpu->kvm->arch.mmu;
484
485 /*
486 * This vCPU may have been created after mpidr_data was initialized.
487 * Throw out the pre-computed mappings if that is the case which forces
488 * KVM to fall back to iteratively searching the vCPUs.
489 */
490 kvm_destroy_mpidr_data(vcpu->kvm);
491
492 err = kvm_vgic_vcpu_init(vcpu);
493 if (err)
494 return err;
495
496 err = kvm_share_hyp(vcpu, vcpu + 1);
497 if (err)
498 kvm_vgic_vcpu_destroy(vcpu);
499
500 return err;
501 }
502
kvm_arch_vcpu_postcreate(struct kvm_vcpu * vcpu)503 void kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu)
504 {
505 }
506
kvm_arch_vcpu_destroy(struct kvm_vcpu * vcpu)507 void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu)
508 {
509 if (!is_protected_kvm_enabled())
510 kvm_mmu_free_memory_cache(&vcpu->arch.mmu_page_cache);
511 else
512 free_hyp_memcache(&vcpu->arch.pkvm_memcache);
513 kvm_timer_vcpu_terminate(vcpu);
514 kvm_pmu_vcpu_destroy(vcpu);
515 kvm_vgic_vcpu_destroy(vcpu);
516 kvm_arm_vcpu_destroy(vcpu);
517 }
518
kvm_arch_vcpu_blocking(struct kvm_vcpu * vcpu)519 void kvm_arch_vcpu_blocking(struct kvm_vcpu *vcpu)
520 {
521
522 }
523
kvm_arch_vcpu_unblocking(struct kvm_vcpu * vcpu)524 void kvm_arch_vcpu_unblocking(struct kvm_vcpu *vcpu)
525 {
526
527 }
528
vcpu_set_pauth_traps(struct kvm_vcpu * vcpu)529 static void vcpu_set_pauth_traps(struct kvm_vcpu *vcpu)
530 {
531 if (vcpu_has_ptrauth(vcpu) && !is_protected_kvm_enabled()) {
532 /*
533 * Either we're running an L2 guest, and the API/APK bits come
534 * from L1's HCR_EL2, or API/APK are both set.
535 */
536 if (unlikely(is_nested_ctxt(vcpu))) {
537 u64 val;
538
539 val = __vcpu_sys_reg(vcpu, HCR_EL2);
540 val &= (HCR_API | HCR_APK);
541 vcpu->arch.hcr_el2 &= ~(HCR_API | HCR_APK);
542 vcpu->arch.hcr_el2 |= val;
543 } else {
544 vcpu->arch.hcr_el2 |= (HCR_API | HCR_APK);
545 }
546
547 /*
548 * Save the host keys if there is any chance for the guest
549 * to use pauth, as the entry code will reload the guest
550 * keys in that case.
551 */
552 if (vcpu->arch.hcr_el2 & (HCR_API | HCR_APK)) {
553 struct kvm_cpu_context *ctxt;
554
555 ctxt = this_cpu_ptr_hyp_sym(kvm_hyp_ctxt);
556 ptrauth_save_keys(ctxt);
557 }
558 }
559 }
560
kvm_vcpu_should_clear_twi(struct kvm_vcpu * vcpu)561 static bool kvm_vcpu_should_clear_twi(struct kvm_vcpu *vcpu)
562 {
563 if (unlikely(kvm_wfi_trap_policy != KVM_WFX_NOTRAP_SINGLE_TASK))
564 return kvm_wfi_trap_policy == KVM_WFX_NOTRAP;
565
566 return single_task_running() &&
567 (atomic_read(&vcpu->arch.vgic_cpu.vgic_v3.its_vpe.vlpi_count) ||
568 vcpu->kvm->arch.vgic.nassgireq);
569 }
570
kvm_vcpu_should_clear_twe(struct kvm_vcpu * vcpu)571 static bool kvm_vcpu_should_clear_twe(struct kvm_vcpu *vcpu)
572 {
573 if (unlikely(kvm_wfe_trap_policy != KVM_WFX_NOTRAP_SINGLE_TASK))
574 return kvm_wfe_trap_policy == KVM_WFX_NOTRAP;
575
576 return single_task_running();
577 }
578
kvm_arch_vcpu_load(struct kvm_vcpu * vcpu,int cpu)579 void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
580 {
581 struct kvm_s2_mmu *mmu;
582 int *last_ran;
583
584 if (is_protected_kvm_enabled())
585 goto nommu;
586
587 if (vcpu_has_nv(vcpu))
588 kvm_vcpu_load_hw_mmu(vcpu);
589
590 mmu = vcpu->arch.hw_mmu;
591 last_ran = this_cpu_ptr(mmu->last_vcpu_ran);
592
593 /*
594 * Ensure a VMID is allocated for the MMU before programming VTTBR_EL2,
595 * which happens eagerly in VHE.
596 *
597 * Also, the VMID allocator only preserves VMIDs that are active at the
598 * time of rollover, so KVM might need to grab a new VMID for the MMU if
599 * this is called from kvm_sched_in().
600 */
601 kvm_arm_vmid_update(&mmu->vmid);
602
603 /*
604 * We guarantee that both TLBs and I-cache are private to each
605 * vcpu. If detecting that a vcpu from the same VM has
606 * previously run on the same physical CPU, call into the
607 * hypervisor code to nuke the relevant contexts.
608 *
609 * We might get preempted before the vCPU actually runs, but
610 * over-invalidation doesn't affect correctness.
611 */
612 if (*last_ran != vcpu->vcpu_idx) {
613 kvm_call_hyp(__kvm_flush_cpu_context, mmu);
614 *last_ran = vcpu->vcpu_idx;
615 }
616
617 nommu:
618 vcpu->cpu = cpu;
619
620 /*
621 * The timer must be loaded before the vgic to correctly set up physical
622 * interrupt deactivation in nested state (e.g. timer interrupt).
623 */
624 kvm_timer_vcpu_load(vcpu);
625 kvm_vgic_load(vcpu);
626 kvm_vcpu_load_debug(vcpu);
627 if (has_vhe())
628 kvm_vcpu_load_vhe(vcpu);
629 kvm_arch_vcpu_load_fp(vcpu);
630 kvm_vcpu_pmu_restore_guest(vcpu);
631 if (kvm_arm_is_pvtime_enabled(&vcpu->arch))
632 kvm_make_request(KVM_REQ_RECORD_STEAL, vcpu);
633
634 if (kvm_vcpu_should_clear_twe(vcpu))
635 vcpu->arch.hcr_el2 &= ~HCR_TWE;
636 else
637 vcpu->arch.hcr_el2 |= HCR_TWE;
638
639 if (kvm_vcpu_should_clear_twi(vcpu))
640 vcpu->arch.hcr_el2 &= ~HCR_TWI;
641 else
642 vcpu->arch.hcr_el2 |= HCR_TWI;
643
644 vcpu_set_pauth_traps(vcpu);
645
646 if (is_protected_kvm_enabled()) {
647 kvm_call_hyp_nvhe(__pkvm_vcpu_load,
648 vcpu->kvm->arch.pkvm.handle,
649 vcpu->vcpu_idx, vcpu->arch.hcr_el2);
650 kvm_call_hyp(__vgic_v3_restore_vmcr_aprs,
651 &vcpu->arch.vgic_cpu.vgic_v3);
652 }
653
654 if (!cpumask_test_cpu(cpu, vcpu->kvm->arch.supported_cpus))
655 vcpu_set_on_unsupported_cpu(vcpu);
656 }
657
kvm_arch_vcpu_put(struct kvm_vcpu * vcpu)658 void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu)
659 {
660 if (is_protected_kvm_enabled()) {
661 kvm_call_hyp(__vgic_v3_save_vmcr_aprs,
662 &vcpu->arch.vgic_cpu.vgic_v3);
663 kvm_call_hyp_nvhe(__pkvm_vcpu_put);
664 }
665
666 kvm_vcpu_put_debug(vcpu);
667 kvm_arch_vcpu_put_fp(vcpu);
668 if (has_vhe())
669 kvm_vcpu_put_vhe(vcpu);
670 kvm_timer_vcpu_put(vcpu);
671 kvm_vgic_put(vcpu);
672 kvm_vcpu_pmu_restore_host(vcpu);
673 if (vcpu_has_nv(vcpu))
674 kvm_vcpu_put_hw_mmu(vcpu);
675 kvm_arm_vmid_clear_active();
676
677 vcpu_clear_on_unsupported_cpu(vcpu);
678 vcpu->cpu = -1;
679 }
680
__kvm_arm_vcpu_power_off(struct kvm_vcpu * vcpu)681 static void __kvm_arm_vcpu_power_off(struct kvm_vcpu *vcpu)
682 {
683 WRITE_ONCE(vcpu->arch.mp_state.mp_state, KVM_MP_STATE_STOPPED);
684 kvm_make_request(KVM_REQ_SLEEP, vcpu);
685 kvm_vcpu_kick(vcpu);
686 }
687
kvm_arm_vcpu_power_off(struct kvm_vcpu * vcpu)688 void kvm_arm_vcpu_power_off(struct kvm_vcpu *vcpu)
689 {
690 spin_lock(&vcpu->arch.mp_state_lock);
691 __kvm_arm_vcpu_power_off(vcpu);
692 spin_unlock(&vcpu->arch.mp_state_lock);
693 }
694
kvm_arm_vcpu_stopped(struct kvm_vcpu * vcpu)695 bool kvm_arm_vcpu_stopped(struct kvm_vcpu *vcpu)
696 {
697 return READ_ONCE(vcpu->arch.mp_state.mp_state) == KVM_MP_STATE_STOPPED;
698 }
699
kvm_arm_vcpu_suspend(struct kvm_vcpu * vcpu)700 static void kvm_arm_vcpu_suspend(struct kvm_vcpu *vcpu)
701 {
702 WRITE_ONCE(vcpu->arch.mp_state.mp_state, KVM_MP_STATE_SUSPENDED);
703 kvm_make_request(KVM_REQ_SUSPEND, vcpu);
704 kvm_vcpu_kick(vcpu);
705 }
706
kvm_arm_vcpu_suspended(struct kvm_vcpu * vcpu)707 static bool kvm_arm_vcpu_suspended(struct kvm_vcpu *vcpu)
708 {
709 return READ_ONCE(vcpu->arch.mp_state.mp_state) == KVM_MP_STATE_SUSPENDED;
710 }
711
kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu * vcpu,struct kvm_mp_state * mp_state)712 int kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu *vcpu,
713 struct kvm_mp_state *mp_state)
714 {
715 *mp_state = READ_ONCE(vcpu->arch.mp_state);
716
717 return 0;
718 }
719
kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu * vcpu,struct kvm_mp_state * mp_state)720 int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu,
721 struct kvm_mp_state *mp_state)
722 {
723 int ret = 0;
724
725 spin_lock(&vcpu->arch.mp_state_lock);
726
727 switch (mp_state->mp_state) {
728 case KVM_MP_STATE_RUNNABLE:
729 WRITE_ONCE(vcpu->arch.mp_state, *mp_state);
730 break;
731 case KVM_MP_STATE_STOPPED:
732 __kvm_arm_vcpu_power_off(vcpu);
733 break;
734 case KVM_MP_STATE_SUSPENDED:
735 kvm_arm_vcpu_suspend(vcpu);
736 break;
737 default:
738 ret = -EINVAL;
739 }
740
741 spin_unlock(&vcpu->arch.mp_state_lock);
742
743 return ret;
744 }
745
746 /**
747 * kvm_arch_vcpu_runnable - determine if the vcpu can be scheduled
748 * @v: The VCPU pointer
749 *
750 * If the guest CPU is not waiting for interrupts or an interrupt line is
751 * asserted, the CPU is by definition runnable.
752 */
kvm_arch_vcpu_runnable(struct kvm_vcpu * v)753 int kvm_arch_vcpu_runnable(struct kvm_vcpu *v)
754 {
755 bool irq_lines = *vcpu_hcr(v) & (HCR_VI | HCR_VF | HCR_VSE);
756
757 return ((irq_lines || kvm_vgic_vcpu_pending_irq(v))
758 && !kvm_arm_vcpu_stopped(v) && !v->arch.pause);
759 }
760
kvm_arch_vcpu_in_kernel(struct kvm_vcpu * vcpu)761 bool kvm_arch_vcpu_in_kernel(struct kvm_vcpu *vcpu)
762 {
763 return vcpu_mode_priv(vcpu);
764 }
765
766 #ifdef CONFIG_GUEST_PERF_EVENTS
kvm_arch_vcpu_get_ip(struct kvm_vcpu * vcpu)767 unsigned long kvm_arch_vcpu_get_ip(struct kvm_vcpu *vcpu)
768 {
769 return *vcpu_pc(vcpu);
770 }
771 #endif
772
kvm_init_mpidr_data(struct kvm * kvm)773 static void kvm_init_mpidr_data(struct kvm *kvm)
774 {
775 struct kvm_mpidr_data *data = NULL;
776 unsigned long c, mask, nr_entries;
777 u64 aff_set = 0, aff_clr = ~0UL;
778 struct kvm_vcpu *vcpu;
779
780 mutex_lock(&kvm->arch.config_lock);
781
782 if (rcu_access_pointer(kvm->arch.mpidr_data) ||
783 atomic_read(&kvm->online_vcpus) == 1)
784 goto out;
785
786 kvm_for_each_vcpu(c, vcpu, kvm) {
787 u64 aff = kvm_vcpu_get_mpidr_aff(vcpu);
788 aff_set |= aff;
789 aff_clr &= aff;
790 }
791
792 /*
793 * A significant bit can be either 0 or 1, and will only appear in
794 * aff_set. Use aff_clr to weed out the useless stuff.
795 */
796 mask = aff_set ^ aff_clr;
797 nr_entries = BIT_ULL(hweight_long(mask));
798
799 /*
800 * Don't let userspace fool us. If we need more than a single page
801 * to describe the compressed MPIDR array, just fall back to the
802 * iterative method. Single vcpu VMs do not need this either.
803 */
804 if (struct_size(data, cmpidr_to_idx, nr_entries) <= PAGE_SIZE)
805 data = kzalloc(struct_size(data, cmpidr_to_idx, nr_entries),
806 GFP_KERNEL_ACCOUNT);
807
808 if (!data)
809 goto out;
810
811 data->mpidr_mask = mask;
812
813 kvm_for_each_vcpu(c, vcpu, kvm) {
814 u64 aff = kvm_vcpu_get_mpidr_aff(vcpu);
815 u16 index = kvm_mpidr_index(data, aff);
816
817 data->cmpidr_to_idx[index] = c;
818 }
819
820 rcu_assign_pointer(kvm->arch.mpidr_data, data);
821 out:
822 mutex_unlock(&kvm->arch.config_lock);
823 }
824
825 /*
826 * Handle both the initialisation that is being done when the vcpu is
827 * run for the first time, as well as the updates that must be
828 * performed each time we get a new thread dealing with this vcpu.
829 */
kvm_arch_vcpu_run_pid_change(struct kvm_vcpu * vcpu)830 int kvm_arch_vcpu_run_pid_change(struct kvm_vcpu *vcpu)
831 {
832 struct kvm *kvm = vcpu->kvm;
833 int ret;
834
835 if (!kvm_vcpu_initialized(vcpu))
836 return -ENOEXEC;
837
838 if (!kvm_arm_vcpu_is_finalized(vcpu))
839 return -EPERM;
840
841 if (likely(vcpu_has_run_once(vcpu)))
842 return 0;
843
844 kvm_init_mpidr_data(kvm);
845
846 if (likely(irqchip_in_kernel(kvm))) {
847 /*
848 * Map the VGIC hardware resources before running a vcpu the
849 * first time on this VM.
850 */
851 ret = kvm_vgic_map_resources(kvm);
852 if (ret)
853 return ret;
854 }
855
856 ret = kvm_finalize_sys_regs(vcpu);
857 if (ret)
858 return ret;
859
860 if (vcpu_has_nv(vcpu)) {
861 ret = kvm_vcpu_allocate_vncr_tlb(vcpu);
862 if (ret)
863 return ret;
864
865 ret = kvm_vgic_vcpu_nv_init(vcpu);
866 if (ret)
867 return ret;
868 }
869
870 /*
871 * This needs to happen after any restriction has been applied
872 * to the feature set.
873 */
874 kvm_calculate_traps(vcpu);
875
876 ret = kvm_timer_enable(vcpu);
877 if (ret)
878 return ret;
879
880 if (kvm_vcpu_has_pmu(vcpu)) {
881 ret = kvm_arm_pmu_v3_enable(vcpu);
882 if (ret)
883 return ret;
884 }
885
886 if (is_protected_kvm_enabled()) {
887 ret = pkvm_create_hyp_vm(kvm);
888 if (ret)
889 return ret;
890
891 ret = pkvm_create_hyp_vcpu(vcpu);
892 if (ret)
893 return ret;
894 }
895
896 mutex_lock(&kvm->arch.config_lock);
897 set_bit(KVM_ARCH_FLAG_HAS_RAN_ONCE, &kvm->arch.flags);
898 mutex_unlock(&kvm->arch.config_lock);
899
900 return ret;
901 }
902
kvm_arch_intc_initialized(struct kvm * kvm)903 bool kvm_arch_intc_initialized(struct kvm *kvm)
904 {
905 return vgic_initialized(kvm);
906 }
907
kvm_arm_halt_guest(struct kvm * kvm)908 void kvm_arm_halt_guest(struct kvm *kvm)
909 {
910 unsigned long i;
911 struct kvm_vcpu *vcpu;
912
913 kvm_for_each_vcpu(i, vcpu, kvm)
914 vcpu->arch.pause = true;
915 kvm_make_all_cpus_request(kvm, KVM_REQ_SLEEP);
916 }
917
kvm_arm_resume_guest(struct kvm * kvm)918 void kvm_arm_resume_guest(struct kvm *kvm)
919 {
920 unsigned long i;
921 struct kvm_vcpu *vcpu;
922
923 kvm_for_each_vcpu(i, vcpu, kvm) {
924 vcpu->arch.pause = false;
925 __kvm_vcpu_wake_up(vcpu);
926 }
927 }
928
kvm_vcpu_sleep(struct kvm_vcpu * vcpu)929 static void kvm_vcpu_sleep(struct kvm_vcpu *vcpu)
930 {
931 struct rcuwait *wait = kvm_arch_vcpu_get_wait(vcpu);
932
933 rcuwait_wait_event(wait,
934 (!kvm_arm_vcpu_stopped(vcpu)) && (!vcpu->arch.pause),
935 TASK_INTERRUPTIBLE);
936
937 if (kvm_arm_vcpu_stopped(vcpu) || vcpu->arch.pause) {
938 /* Awaken to handle a signal, request we sleep again later. */
939 kvm_make_request(KVM_REQ_SLEEP, vcpu);
940 }
941
942 /*
943 * Make sure we will observe a potential reset request if we've
944 * observed a change to the power state. Pairs with the smp_wmb() in
945 * kvm_psci_vcpu_on().
946 */
947 smp_rmb();
948 }
949
950 /**
951 * kvm_vcpu_wfi - emulate Wait-For-Interrupt behavior
952 * @vcpu: The VCPU pointer
953 *
954 * Suspend execution of a vCPU until a valid wake event is detected, i.e. until
955 * the vCPU is runnable. The vCPU may or may not be scheduled out, depending
956 * on when a wake event arrives, e.g. there may already be a pending wake event.
957 */
kvm_vcpu_wfi(struct kvm_vcpu * vcpu)958 void kvm_vcpu_wfi(struct kvm_vcpu *vcpu)
959 {
960 /*
961 * Sync back the state of the GIC CPU interface so that we have
962 * the latest PMR and group enables. This ensures that
963 * kvm_arch_vcpu_runnable has up-to-date data to decide whether
964 * we have pending interrupts, e.g. when determining if the
965 * vCPU should block.
966 *
967 * For the same reason, we want to tell GICv4 that we need
968 * doorbells to be signalled, should an interrupt become pending.
969 */
970 preempt_disable();
971 vcpu_set_flag(vcpu, IN_WFI);
972 kvm_vgic_put(vcpu);
973 preempt_enable();
974
975 kvm_vcpu_halt(vcpu);
976 vcpu_clear_flag(vcpu, IN_WFIT);
977
978 preempt_disable();
979 vcpu_clear_flag(vcpu, IN_WFI);
980 kvm_vgic_load(vcpu);
981 preempt_enable();
982 }
983
kvm_vcpu_suspend(struct kvm_vcpu * vcpu)984 static int kvm_vcpu_suspend(struct kvm_vcpu *vcpu)
985 {
986 if (!kvm_arm_vcpu_suspended(vcpu))
987 return 1;
988
989 kvm_vcpu_wfi(vcpu);
990
991 /*
992 * The suspend state is sticky; we do not leave it until userspace
993 * explicitly marks the vCPU as runnable. Request that we suspend again
994 * later.
995 */
996 kvm_make_request(KVM_REQ_SUSPEND, vcpu);
997
998 /*
999 * Check to make sure the vCPU is actually runnable. If so, exit to
1000 * userspace informing it of the wakeup condition.
1001 */
1002 if (kvm_arch_vcpu_runnable(vcpu)) {
1003 memset(&vcpu->run->system_event, 0, sizeof(vcpu->run->system_event));
1004 vcpu->run->system_event.type = KVM_SYSTEM_EVENT_WAKEUP;
1005 vcpu->run->exit_reason = KVM_EXIT_SYSTEM_EVENT;
1006 return 0;
1007 }
1008
1009 /*
1010 * Otherwise, we were unblocked to process a different event, such as a
1011 * pending signal. Return 1 and allow kvm_arch_vcpu_ioctl_run() to
1012 * process the event.
1013 */
1014 return 1;
1015 }
1016
1017 /**
1018 * check_vcpu_requests - check and handle pending vCPU requests
1019 * @vcpu: the VCPU pointer
1020 *
1021 * Return: 1 if we should enter the guest
1022 * 0 if we should exit to userspace
1023 * < 0 if we should exit to userspace, where the return value indicates
1024 * an error
1025 */
check_vcpu_requests(struct kvm_vcpu * vcpu)1026 static int check_vcpu_requests(struct kvm_vcpu *vcpu)
1027 {
1028 if (kvm_request_pending(vcpu)) {
1029 if (kvm_check_request(KVM_REQ_VM_DEAD, vcpu))
1030 return -EIO;
1031
1032 if (kvm_check_request(KVM_REQ_SLEEP, vcpu))
1033 kvm_vcpu_sleep(vcpu);
1034
1035 if (kvm_check_request(KVM_REQ_VCPU_RESET, vcpu))
1036 kvm_reset_vcpu(vcpu);
1037
1038 /*
1039 * Clear IRQ_PENDING requests that were made to guarantee
1040 * that a VCPU sees new virtual interrupts.
1041 */
1042 kvm_check_request(KVM_REQ_IRQ_PENDING, vcpu);
1043
1044 if (kvm_check_request(KVM_REQ_RECORD_STEAL, vcpu))
1045 kvm_update_stolen_time(vcpu);
1046
1047 if (kvm_check_request(KVM_REQ_RELOAD_GICv4, vcpu)) {
1048 /* The distributor enable bits were changed */
1049 preempt_disable();
1050 vgic_v4_put(vcpu);
1051 vgic_v4_load(vcpu);
1052 preempt_enable();
1053 }
1054
1055 if (kvm_check_request(KVM_REQ_RELOAD_PMU, vcpu))
1056 kvm_vcpu_reload_pmu(vcpu);
1057
1058 if (kvm_check_request(KVM_REQ_RESYNC_PMU_EL0, vcpu))
1059 kvm_vcpu_pmu_restore_guest(vcpu);
1060
1061 if (kvm_check_request(KVM_REQ_SUSPEND, vcpu))
1062 return kvm_vcpu_suspend(vcpu);
1063
1064 if (kvm_dirty_ring_check_request(vcpu))
1065 return 0;
1066
1067 check_nested_vcpu_requests(vcpu);
1068 }
1069
1070 return 1;
1071 }
1072
vcpu_mode_is_bad_32bit(struct kvm_vcpu * vcpu)1073 static bool vcpu_mode_is_bad_32bit(struct kvm_vcpu *vcpu)
1074 {
1075 if (likely(!vcpu_mode_is_32bit(vcpu)))
1076 return false;
1077
1078 if (vcpu_has_nv(vcpu))
1079 return true;
1080
1081 return !kvm_supports_32bit_el0();
1082 }
1083
1084 /**
1085 * kvm_vcpu_exit_request - returns true if the VCPU should *not* enter the guest
1086 * @vcpu: The VCPU pointer
1087 * @ret: Pointer to write optional return code
1088 *
1089 * Returns: true if the VCPU needs to return to a preemptible + interruptible
1090 * and skip guest entry.
1091 *
1092 * This function disambiguates between two different types of exits: exits to a
1093 * preemptible + interruptible kernel context and exits to userspace. For an
1094 * exit to userspace, this function will write the return code to ret and return
1095 * true. For an exit to preemptible + interruptible kernel context (i.e. check
1096 * for pending work and re-enter), return true without writing to ret.
1097 */
kvm_vcpu_exit_request(struct kvm_vcpu * vcpu,int * ret)1098 static bool kvm_vcpu_exit_request(struct kvm_vcpu *vcpu, int *ret)
1099 {
1100 struct kvm_run *run = vcpu->run;
1101
1102 /*
1103 * If we're using a userspace irqchip, then check if we need
1104 * to tell a userspace irqchip about timer or PMU level
1105 * changes and if so, exit to userspace (the actual level
1106 * state gets updated in kvm_timer_update_run and
1107 * kvm_pmu_update_run below).
1108 */
1109 if (unlikely(!irqchip_in_kernel(vcpu->kvm))) {
1110 if (kvm_timer_should_notify_user(vcpu) ||
1111 kvm_pmu_should_notify_user(vcpu)) {
1112 *ret = -EINTR;
1113 run->exit_reason = KVM_EXIT_INTR;
1114 return true;
1115 }
1116 }
1117
1118 if (unlikely(vcpu_on_unsupported_cpu(vcpu))) {
1119 run->exit_reason = KVM_EXIT_FAIL_ENTRY;
1120 run->fail_entry.hardware_entry_failure_reason = KVM_EXIT_FAIL_ENTRY_CPU_UNSUPPORTED;
1121 run->fail_entry.cpu = smp_processor_id();
1122 *ret = 0;
1123 return true;
1124 }
1125
1126 return kvm_request_pending(vcpu) ||
1127 xfer_to_guest_mode_work_pending();
1128 }
1129
1130 /*
1131 * Actually run the vCPU, entering an RCU extended quiescent state (EQS) while
1132 * the vCPU is running.
1133 *
1134 * This must be noinstr as instrumentation may make use of RCU, and this is not
1135 * safe during the EQS.
1136 */
kvm_arm_vcpu_enter_exit(struct kvm_vcpu * vcpu)1137 static int noinstr kvm_arm_vcpu_enter_exit(struct kvm_vcpu *vcpu)
1138 {
1139 int ret;
1140
1141 guest_state_enter_irqoff();
1142 ret = kvm_call_hyp_ret(__kvm_vcpu_run, vcpu);
1143 guest_state_exit_irqoff();
1144
1145 return ret;
1146 }
1147
1148 /**
1149 * kvm_arch_vcpu_ioctl_run - the main VCPU run function to execute guest code
1150 * @vcpu: The VCPU pointer
1151 *
1152 * This function is called through the VCPU_RUN ioctl called from user space. It
1153 * will execute VM code in a loop until the time slice for the process is used
1154 * or some emulation is needed from user space in which case the function will
1155 * return with return value 0 and with the kvm_run structure filled in with the
1156 * required data for the requested emulation.
1157 */
kvm_arch_vcpu_ioctl_run(struct kvm_vcpu * vcpu)1158 int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu)
1159 {
1160 struct kvm_run *run = vcpu->run;
1161 int ret;
1162
1163 if (run->exit_reason == KVM_EXIT_MMIO) {
1164 ret = kvm_handle_mmio_return(vcpu);
1165 if (ret <= 0)
1166 return ret;
1167 }
1168
1169 vcpu_load(vcpu);
1170
1171 if (!vcpu->wants_to_run) {
1172 ret = -EINTR;
1173 goto out;
1174 }
1175
1176 kvm_sigset_activate(vcpu);
1177
1178 ret = 1;
1179 run->exit_reason = KVM_EXIT_UNKNOWN;
1180 run->flags = 0;
1181 while (ret > 0) {
1182 /*
1183 * Check conditions before entering the guest
1184 */
1185 ret = kvm_xfer_to_guest_mode_handle_work(vcpu);
1186 if (!ret)
1187 ret = 1;
1188
1189 if (ret > 0)
1190 ret = check_vcpu_requests(vcpu);
1191
1192 /*
1193 * Preparing the interrupts to be injected also
1194 * involves poking the GIC, which must be done in a
1195 * non-preemptible context.
1196 */
1197 preempt_disable();
1198
1199 kvm_nested_flush_hwstate(vcpu);
1200
1201 if (kvm_vcpu_has_pmu(vcpu))
1202 kvm_pmu_flush_hwstate(vcpu);
1203
1204 local_irq_disable();
1205
1206 kvm_vgic_flush_hwstate(vcpu);
1207
1208 kvm_pmu_update_vcpu_events(vcpu);
1209
1210 /*
1211 * Ensure we set mode to IN_GUEST_MODE after we disable
1212 * interrupts and before the final VCPU requests check.
1213 * See the comment in kvm_vcpu_exiting_guest_mode() and
1214 * Documentation/virt/kvm/vcpu-requests.rst
1215 */
1216 smp_store_mb(vcpu->mode, IN_GUEST_MODE);
1217
1218 if (ret <= 0 || kvm_vcpu_exit_request(vcpu, &ret)) {
1219 vcpu->mode = OUTSIDE_GUEST_MODE;
1220 isb(); /* Ensure work in x_flush_hwstate is committed */
1221 if (kvm_vcpu_has_pmu(vcpu))
1222 kvm_pmu_sync_hwstate(vcpu);
1223 if (unlikely(!irqchip_in_kernel(vcpu->kvm)))
1224 kvm_timer_sync_user(vcpu);
1225 kvm_vgic_sync_hwstate(vcpu);
1226 local_irq_enable();
1227 preempt_enable();
1228 continue;
1229 }
1230
1231 kvm_arch_vcpu_ctxflush_fp(vcpu);
1232
1233 /**************************************************************
1234 * Enter the guest
1235 */
1236 trace_kvm_entry(*vcpu_pc(vcpu));
1237 guest_timing_enter_irqoff();
1238
1239 ret = kvm_arm_vcpu_enter_exit(vcpu);
1240
1241 vcpu->mode = OUTSIDE_GUEST_MODE;
1242 vcpu->stat.exits++;
1243 /*
1244 * Back from guest
1245 *************************************************************/
1246
1247 /*
1248 * We must sync the PMU state before the vgic state so
1249 * that the vgic can properly sample the updated state of the
1250 * interrupt line.
1251 */
1252 if (kvm_vcpu_has_pmu(vcpu))
1253 kvm_pmu_sync_hwstate(vcpu);
1254
1255 /*
1256 * Sync the vgic state before syncing the timer state because
1257 * the timer code needs to know if the virtual timer
1258 * interrupts are active.
1259 */
1260 kvm_vgic_sync_hwstate(vcpu);
1261
1262 /*
1263 * Sync the timer hardware state before enabling interrupts as
1264 * we don't want vtimer interrupts to race with syncing the
1265 * timer virtual interrupt state.
1266 */
1267 if (unlikely(!irqchip_in_kernel(vcpu->kvm)))
1268 kvm_timer_sync_user(vcpu);
1269
1270 if (is_hyp_ctxt(vcpu))
1271 kvm_timer_sync_nested(vcpu);
1272
1273 kvm_arch_vcpu_ctxsync_fp(vcpu);
1274
1275 /*
1276 * We must ensure that any pending interrupts are taken before
1277 * we exit guest timing so that timer ticks are accounted as
1278 * guest time. Transiently unmask interrupts so that any
1279 * pending interrupts are taken.
1280 *
1281 * Per ARM DDI 0487G.b section D1.13.4, an ISB (or other
1282 * context synchronization event) is necessary to ensure that
1283 * pending interrupts are taken.
1284 */
1285 if (ARM_EXCEPTION_CODE(ret) == ARM_EXCEPTION_IRQ) {
1286 local_irq_enable();
1287 isb();
1288 local_irq_disable();
1289 }
1290
1291 guest_timing_exit_irqoff();
1292
1293 local_irq_enable();
1294
1295 trace_kvm_exit(ret, kvm_vcpu_trap_get_class(vcpu), *vcpu_pc(vcpu));
1296
1297 /* Exit types that need handling before we can be preempted */
1298 handle_exit_early(vcpu, ret);
1299
1300 kvm_nested_sync_hwstate(vcpu);
1301
1302 preempt_enable();
1303
1304 /*
1305 * The ARMv8 architecture doesn't give the hypervisor
1306 * a mechanism to prevent a guest from dropping to AArch32 EL0
1307 * if implemented by the CPU. If we spot the guest in such
1308 * state and that we decided it wasn't supposed to do so (like
1309 * with the asymmetric AArch32 case), return to userspace with
1310 * a fatal error.
1311 */
1312 if (vcpu_mode_is_bad_32bit(vcpu)) {
1313 /*
1314 * As we have caught the guest red-handed, decide that
1315 * it isn't fit for purpose anymore by making the vcpu
1316 * invalid. The VMM can try and fix it by issuing a
1317 * KVM_ARM_VCPU_INIT if it really wants to.
1318 */
1319 vcpu_clear_flag(vcpu, VCPU_INITIALIZED);
1320 ret = ARM_EXCEPTION_IL;
1321 }
1322
1323 ret = handle_exit(vcpu, ret);
1324 }
1325
1326 /* Tell userspace about in-kernel device output levels */
1327 if (unlikely(!irqchip_in_kernel(vcpu->kvm))) {
1328 kvm_timer_update_run(vcpu);
1329 kvm_pmu_update_run(vcpu);
1330 }
1331
1332 kvm_sigset_deactivate(vcpu);
1333
1334 out:
1335 /*
1336 * In the unlikely event that we are returning to userspace
1337 * with pending exceptions or PC adjustment, commit these
1338 * adjustments in order to give userspace a consistent view of
1339 * the vcpu state. Note that this relies on __kvm_adjust_pc()
1340 * being preempt-safe on VHE.
1341 */
1342 if (unlikely(vcpu_get_flag(vcpu, PENDING_EXCEPTION) ||
1343 vcpu_get_flag(vcpu, INCREMENT_PC)))
1344 kvm_call_hyp(__kvm_adjust_pc, vcpu);
1345
1346 vcpu_put(vcpu);
1347 return ret;
1348 }
1349
vcpu_interrupt_line(struct kvm_vcpu * vcpu,int number,bool level)1350 static int vcpu_interrupt_line(struct kvm_vcpu *vcpu, int number, bool level)
1351 {
1352 int bit_index;
1353 bool set;
1354 unsigned long *hcr;
1355
1356 if (number == KVM_ARM_IRQ_CPU_IRQ)
1357 bit_index = __ffs(HCR_VI);
1358 else /* KVM_ARM_IRQ_CPU_FIQ */
1359 bit_index = __ffs(HCR_VF);
1360
1361 hcr = vcpu_hcr(vcpu);
1362 if (level)
1363 set = test_and_set_bit(bit_index, hcr);
1364 else
1365 set = test_and_clear_bit(bit_index, hcr);
1366
1367 /*
1368 * If we didn't change anything, no need to wake up or kick other CPUs
1369 */
1370 if (set == level)
1371 return 0;
1372
1373 /*
1374 * The vcpu irq_lines field was updated, wake up sleeping VCPUs and
1375 * trigger a world-switch round on the running physical CPU to set the
1376 * virtual IRQ/FIQ fields in the HCR appropriately.
1377 */
1378 kvm_make_request(KVM_REQ_IRQ_PENDING, vcpu);
1379 kvm_vcpu_kick(vcpu);
1380
1381 return 0;
1382 }
1383
kvm_vm_ioctl_irq_line(struct kvm * kvm,struct kvm_irq_level * irq_level,bool line_status)1384 int kvm_vm_ioctl_irq_line(struct kvm *kvm, struct kvm_irq_level *irq_level,
1385 bool line_status)
1386 {
1387 u32 irq = irq_level->irq;
1388 unsigned int irq_type, vcpu_id, irq_num;
1389 struct kvm_vcpu *vcpu = NULL;
1390 bool level = irq_level->level;
1391
1392 irq_type = (irq >> KVM_ARM_IRQ_TYPE_SHIFT) & KVM_ARM_IRQ_TYPE_MASK;
1393 vcpu_id = (irq >> KVM_ARM_IRQ_VCPU_SHIFT) & KVM_ARM_IRQ_VCPU_MASK;
1394 vcpu_id += ((irq >> KVM_ARM_IRQ_VCPU2_SHIFT) & KVM_ARM_IRQ_VCPU2_MASK) * (KVM_ARM_IRQ_VCPU_MASK + 1);
1395 irq_num = (irq >> KVM_ARM_IRQ_NUM_SHIFT) & KVM_ARM_IRQ_NUM_MASK;
1396
1397 trace_kvm_irq_line(irq_type, vcpu_id, irq_num, irq_level->level);
1398
1399 switch (irq_type) {
1400 case KVM_ARM_IRQ_TYPE_CPU:
1401 if (irqchip_in_kernel(kvm))
1402 return -ENXIO;
1403
1404 vcpu = kvm_get_vcpu_by_id(kvm, vcpu_id);
1405 if (!vcpu)
1406 return -EINVAL;
1407
1408 if (irq_num > KVM_ARM_IRQ_CPU_FIQ)
1409 return -EINVAL;
1410
1411 return vcpu_interrupt_line(vcpu, irq_num, level);
1412 case KVM_ARM_IRQ_TYPE_PPI:
1413 if (!irqchip_in_kernel(kvm))
1414 return -ENXIO;
1415
1416 vcpu = kvm_get_vcpu_by_id(kvm, vcpu_id);
1417 if (!vcpu)
1418 return -EINVAL;
1419
1420 if (irq_num < VGIC_NR_SGIS || irq_num >= VGIC_NR_PRIVATE_IRQS)
1421 return -EINVAL;
1422
1423 return kvm_vgic_inject_irq(kvm, vcpu, irq_num, level, NULL);
1424 case KVM_ARM_IRQ_TYPE_SPI:
1425 if (!irqchip_in_kernel(kvm))
1426 return -ENXIO;
1427
1428 if (irq_num < VGIC_NR_PRIVATE_IRQS)
1429 return -EINVAL;
1430
1431 return kvm_vgic_inject_irq(kvm, NULL, irq_num, level, NULL);
1432 }
1433
1434 return -EINVAL;
1435 }
1436
system_supported_vcpu_features(void)1437 static unsigned long system_supported_vcpu_features(void)
1438 {
1439 unsigned long features = KVM_VCPU_VALID_FEATURES;
1440
1441 if (!cpus_have_final_cap(ARM64_HAS_32BIT_EL1))
1442 clear_bit(KVM_ARM_VCPU_EL1_32BIT, &features);
1443
1444 if (!kvm_supports_guest_pmuv3())
1445 clear_bit(KVM_ARM_VCPU_PMU_V3, &features);
1446
1447 if (!system_supports_sve())
1448 clear_bit(KVM_ARM_VCPU_SVE, &features);
1449
1450 if (!kvm_has_full_ptr_auth()) {
1451 clear_bit(KVM_ARM_VCPU_PTRAUTH_ADDRESS, &features);
1452 clear_bit(KVM_ARM_VCPU_PTRAUTH_GENERIC, &features);
1453 }
1454
1455 if (!cpus_have_final_cap(ARM64_HAS_NESTED_VIRT))
1456 clear_bit(KVM_ARM_VCPU_HAS_EL2, &features);
1457
1458 return features;
1459 }
1460
kvm_vcpu_init_check_features(struct kvm_vcpu * vcpu,const struct kvm_vcpu_init * init)1461 static int kvm_vcpu_init_check_features(struct kvm_vcpu *vcpu,
1462 const struct kvm_vcpu_init *init)
1463 {
1464 unsigned long features = init->features[0];
1465 int i;
1466
1467 if (features & ~KVM_VCPU_VALID_FEATURES)
1468 return -ENOENT;
1469
1470 for (i = 1; i < ARRAY_SIZE(init->features); i++) {
1471 if (init->features[i])
1472 return -ENOENT;
1473 }
1474
1475 if (features & ~system_supported_vcpu_features())
1476 return -EINVAL;
1477
1478 /*
1479 * For now make sure that both address/generic pointer authentication
1480 * features are requested by the userspace together.
1481 */
1482 if (test_bit(KVM_ARM_VCPU_PTRAUTH_ADDRESS, &features) !=
1483 test_bit(KVM_ARM_VCPU_PTRAUTH_GENERIC, &features))
1484 return -EINVAL;
1485
1486 if (!test_bit(KVM_ARM_VCPU_EL1_32BIT, &features))
1487 return 0;
1488
1489 /* MTE is incompatible with AArch32 */
1490 if (kvm_has_mte(vcpu->kvm))
1491 return -EINVAL;
1492
1493 /* NV is incompatible with AArch32 */
1494 if (test_bit(KVM_ARM_VCPU_HAS_EL2, &features))
1495 return -EINVAL;
1496
1497 return 0;
1498 }
1499
kvm_vcpu_init_changed(struct kvm_vcpu * vcpu,const struct kvm_vcpu_init * init)1500 static bool kvm_vcpu_init_changed(struct kvm_vcpu *vcpu,
1501 const struct kvm_vcpu_init *init)
1502 {
1503 unsigned long features = init->features[0];
1504
1505 return !bitmap_equal(vcpu->kvm->arch.vcpu_features, &features,
1506 KVM_VCPU_MAX_FEATURES);
1507 }
1508
kvm_setup_vcpu(struct kvm_vcpu * vcpu)1509 static int kvm_setup_vcpu(struct kvm_vcpu *vcpu)
1510 {
1511 struct kvm *kvm = vcpu->kvm;
1512 int ret = 0;
1513
1514 /*
1515 * When the vCPU has a PMU, but no PMU is set for the guest
1516 * yet, set the default one.
1517 */
1518 if (kvm_vcpu_has_pmu(vcpu) && !kvm->arch.arm_pmu)
1519 ret = kvm_arm_set_default_pmu(kvm);
1520
1521 /* Prepare for nested if required */
1522 if (!ret && vcpu_has_nv(vcpu))
1523 ret = kvm_vcpu_init_nested(vcpu);
1524
1525 return ret;
1526 }
1527
__kvm_vcpu_set_target(struct kvm_vcpu * vcpu,const struct kvm_vcpu_init * init)1528 static int __kvm_vcpu_set_target(struct kvm_vcpu *vcpu,
1529 const struct kvm_vcpu_init *init)
1530 {
1531 unsigned long features = init->features[0];
1532 struct kvm *kvm = vcpu->kvm;
1533 int ret = -EINVAL;
1534
1535 mutex_lock(&kvm->arch.config_lock);
1536
1537 if (test_bit(KVM_ARCH_FLAG_VCPU_FEATURES_CONFIGURED, &kvm->arch.flags) &&
1538 kvm_vcpu_init_changed(vcpu, init))
1539 goto out_unlock;
1540
1541 bitmap_copy(kvm->arch.vcpu_features, &features, KVM_VCPU_MAX_FEATURES);
1542
1543 ret = kvm_setup_vcpu(vcpu);
1544 if (ret)
1545 goto out_unlock;
1546
1547 /* Now we know what it is, we can reset it. */
1548 kvm_reset_vcpu(vcpu);
1549
1550 set_bit(KVM_ARCH_FLAG_VCPU_FEATURES_CONFIGURED, &kvm->arch.flags);
1551 vcpu_set_flag(vcpu, VCPU_INITIALIZED);
1552 ret = 0;
1553 out_unlock:
1554 mutex_unlock(&kvm->arch.config_lock);
1555 return ret;
1556 }
1557
kvm_vcpu_set_target(struct kvm_vcpu * vcpu,const struct kvm_vcpu_init * init)1558 static int kvm_vcpu_set_target(struct kvm_vcpu *vcpu,
1559 const struct kvm_vcpu_init *init)
1560 {
1561 int ret;
1562
1563 if (init->target != KVM_ARM_TARGET_GENERIC_V8 &&
1564 init->target != kvm_target_cpu())
1565 return -EINVAL;
1566
1567 ret = kvm_vcpu_init_check_features(vcpu, init);
1568 if (ret)
1569 return ret;
1570
1571 if (!kvm_vcpu_initialized(vcpu))
1572 return __kvm_vcpu_set_target(vcpu, init);
1573
1574 if (kvm_vcpu_init_changed(vcpu, init))
1575 return -EINVAL;
1576
1577 kvm_reset_vcpu(vcpu);
1578 return 0;
1579 }
1580
kvm_arch_vcpu_ioctl_vcpu_init(struct kvm_vcpu * vcpu,struct kvm_vcpu_init * init)1581 static int kvm_arch_vcpu_ioctl_vcpu_init(struct kvm_vcpu *vcpu,
1582 struct kvm_vcpu_init *init)
1583 {
1584 bool power_off = false;
1585 int ret;
1586
1587 /*
1588 * Treat the power-off vCPU feature as ephemeral. Clear the bit to avoid
1589 * reflecting it in the finalized feature set, thus limiting its scope
1590 * to a single KVM_ARM_VCPU_INIT call.
1591 */
1592 if (init->features[0] & BIT(KVM_ARM_VCPU_POWER_OFF)) {
1593 init->features[0] &= ~BIT(KVM_ARM_VCPU_POWER_OFF);
1594 power_off = true;
1595 }
1596
1597 ret = kvm_vcpu_set_target(vcpu, init);
1598 if (ret)
1599 return ret;
1600
1601 /*
1602 * Ensure a rebooted VM will fault in RAM pages and detect if the
1603 * guest MMU is turned off and flush the caches as needed.
1604 *
1605 * S2FWB enforces all memory accesses to RAM being cacheable,
1606 * ensuring that the data side is always coherent. We still
1607 * need to invalidate the I-cache though, as FWB does *not*
1608 * imply CTR_EL0.DIC.
1609 */
1610 if (vcpu_has_run_once(vcpu)) {
1611 if (!cpus_have_final_cap(ARM64_HAS_STAGE2_FWB))
1612 stage2_unmap_vm(vcpu->kvm);
1613 else
1614 icache_inval_all_pou();
1615 }
1616
1617 vcpu_reset_hcr(vcpu);
1618
1619 /*
1620 * Handle the "start in power-off" case.
1621 */
1622 spin_lock(&vcpu->arch.mp_state_lock);
1623
1624 if (power_off)
1625 __kvm_arm_vcpu_power_off(vcpu);
1626 else
1627 WRITE_ONCE(vcpu->arch.mp_state.mp_state, KVM_MP_STATE_RUNNABLE);
1628
1629 spin_unlock(&vcpu->arch.mp_state_lock);
1630
1631 return 0;
1632 }
1633
kvm_arm_vcpu_set_attr(struct kvm_vcpu * vcpu,struct kvm_device_attr * attr)1634 static int kvm_arm_vcpu_set_attr(struct kvm_vcpu *vcpu,
1635 struct kvm_device_attr *attr)
1636 {
1637 int ret = -ENXIO;
1638
1639 switch (attr->group) {
1640 default:
1641 ret = kvm_arm_vcpu_arch_set_attr(vcpu, attr);
1642 break;
1643 }
1644
1645 return ret;
1646 }
1647
kvm_arm_vcpu_get_attr(struct kvm_vcpu * vcpu,struct kvm_device_attr * attr)1648 static int kvm_arm_vcpu_get_attr(struct kvm_vcpu *vcpu,
1649 struct kvm_device_attr *attr)
1650 {
1651 int ret = -ENXIO;
1652
1653 switch (attr->group) {
1654 default:
1655 ret = kvm_arm_vcpu_arch_get_attr(vcpu, attr);
1656 break;
1657 }
1658
1659 return ret;
1660 }
1661
kvm_arm_vcpu_has_attr(struct kvm_vcpu * vcpu,struct kvm_device_attr * attr)1662 static int kvm_arm_vcpu_has_attr(struct kvm_vcpu *vcpu,
1663 struct kvm_device_attr *attr)
1664 {
1665 int ret = -ENXIO;
1666
1667 switch (attr->group) {
1668 default:
1669 ret = kvm_arm_vcpu_arch_has_attr(vcpu, attr);
1670 break;
1671 }
1672
1673 return ret;
1674 }
1675
kvm_arm_vcpu_get_events(struct kvm_vcpu * vcpu,struct kvm_vcpu_events * events)1676 static int kvm_arm_vcpu_get_events(struct kvm_vcpu *vcpu,
1677 struct kvm_vcpu_events *events)
1678 {
1679 memset(events, 0, sizeof(*events));
1680
1681 return __kvm_arm_vcpu_get_events(vcpu, events);
1682 }
1683
kvm_arm_vcpu_set_events(struct kvm_vcpu * vcpu,struct kvm_vcpu_events * events)1684 static int kvm_arm_vcpu_set_events(struct kvm_vcpu *vcpu,
1685 struct kvm_vcpu_events *events)
1686 {
1687 int i;
1688
1689 /* check whether the reserved field is zero */
1690 for (i = 0; i < ARRAY_SIZE(events->reserved); i++)
1691 if (events->reserved[i])
1692 return -EINVAL;
1693
1694 /* check whether the pad field is zero */
1695 for (i = 0; i < ARRAY_SIZE(events->exception.pad); i++)
1696 if (events->exception.pad[i])
1697 return -EINVAL;
1698
1699 return __kvm_arm_vcpu_set_events(vcpu, events);
1700 }
1701
kvm_arch_vcpu_ioctl(struct file * filp,unsigned int ioctl,unsigned long arg)1702 long kvm_arch_vcpu_ioctl(struct file *filp,
1703 unsigned int ioctl, unsigned long arg)
1704 {
1705 struct kvm_vcpu *vcpu = filp->private_data;
1706 void __user *argp = (void __user *)arg;
1707 struct kvm_device_attr attr;
1708 long r;
1709
1710 switch (ioctl) {
1711 case KVM_ARM_VCPU_INIT: {
1712 struct kvm_vcpu_init init;
1713
1714 r = -EFAULT;
1715 if (copy_from_user(&init, argp, sizeof(init)))
1716 break;
1717
1718 r = kvm_arch_vcpu_ioctl_vcpu_init(vcpu, &init);
1719 break;
1720 }
1721 case KVM_SET_ONE_REG:
1722 case KVM_GET_ONE_REG: {
1723 struct kvm_one_reg reg;
1724
1725 r = -ENOEXEC;
1726 if (unlikely(!kvm_vcpu_initialized(vcpu)))
1727 break;
1728
1729 r = -EFAULT;
1730 if (copy_from_user(®, argp, sizeof(reg)))
1731 break;
1732
1733 /*
1734 * We could owe a reset due to PSCI. Handle the pending reset
1735 * here to ensure userspace register accesses are ordered after
1736 * the reset.
1737 */
1738 if (kvm_check_request(KVM_REQ_VCPU_RESET, vcpu))
1739 kvm_reset_vcpu(vcpu);
1740
1741 if (ioctl == KVM_SET_ONE_REG)
1742 r = kvm_arm_set_reg(vcpu, ®);
1743 else
1744 r = kvm_arm_get_reg(vcpu, ®);
1745 break;
1746 }
1747 case KVM_GET_REG_LIST: {
1748 struct kvm_reg_list __user *user_list = argp;
1749 struct kvm_reg_list reg_list;
1750 unsigned n;
1751
1752 r = -ENOEXEC;
1753 if (unlikely(!kvm_vcpu_initialized(vcpu)))
1754 break;
1755
1756 r = -EPERM;
1757 if (!kvm_arm_vcpu_is_finalized(vcpu))
1758 break;
1759
1760 r = -EFAULT;
1761 if (copy_from_user(®_list, user_list, sizeof(reg_list)))
1762 break;
1763 n = reg_list.n;
1764 reg_list.n = kvm_arm_num_regs(vcpu);
1765 if (copy_to_user(user_list, ®_list, sizeof(reg_list)))
1766 break;
1767 r = -E2BIG;
1768 if (n < reg_list.n)
1769 break;
1770 r = kvm_arm_copy_reg_indices(vcpu, user_list->reg);
1771 break;
1772 }
1773 case KVM_SET_DEVICE_ATTR: {
1774 r = -EFAULT;
1775 if (copy_from_user(&attr, argp, sizeof(attr)))
1776 break;
1777 r = kvm_arm_vcpu_set_attr(vcpu, &attr);
1778 break;
1779 }
1780 case KVM_GET_DEVICE_ATTR: {
1781 r = -EFAULT;
1782 if (copy_from_user(&attr, argp, sizeof(attr)))
1783 break;
1784 r = kvm_arm_vcpu_get_attr(vcpu, &attr);
1785 break;
1786 }
1787 case KVM_HAS_DEVICE_ATTR: {
1788 r = -EFAULT;
1789 if (copy_from_user(&attr, argp, sizeof(attr)))
1790 break;
1791 r = kvm_arm_vcpu_has_attr(vcpu, &attr);
1792 break;
1793 }
1794 case KVM_GET_VCPU_EVENTS: {
1795 struct kvm_vcpu_events events;
1796
1797 if (kvm_arm_vcpu_get_events(vcpu, &events))
1798 return -EINVAL;
1799
1800 if (copy_to_user(argp, &events, sizeof(events)))
1801 return -EFAULT;
1802
1803 return 0;
1804 }
1805 case KVM_SET_VCPU_EVENTS: {
1806 struct kvm_vcpu_events events;
1807
1808 if (copy_from_user(&events, argp, sizeof(events)))
1809 return -EFAULT;
1810
1811 return kvm_arm_vcpu_set_events(vcpu, &events);
1812 }
1813 case KVM_ARM_VCPU_FINALIZE: {
1814 int what;
1815
1816 if (!kvm_vcpu_initialized(vcpu))
1817 return -ENOEXEC;
1818
1819 if (get_user(what, (const int __user *)argp))
1820 return -EFAULT;
1821
1822 return kvm_arm_vcpu_finalize(vcpu, what);
1823 }
1824 default:
1825 r = -EINVAL;
1826 }
1827
1828 return r;
1829 }
1830
kvm_arch_sync_dirty_log(struct kvm * kvm,struct kvm_memory_slot * memslot)1831 void kvm_arch_sync_dirty_log(struct kvm *kvm, struct kvm_memory_slot *memslot)
1832 {
1833
1834 }
1835
kvm_vm_ioctl_set_device_addr(struct kvm * kvm,struct kvm_arm_device_addr * dev_addr)1836 static int kvm_vm_ioctl_set_device_addr(struct kvm *kvm,
1837 struct kvm_arm_device_addr *dev_addr)
1838 {
1839 switch (FIELD_GET(KVM_ARM_DEVICE_ID_MASK, dev_addr->id)) {
1840 case KVM_ARM_DEVICE_VGIC_V2:
1841 if (!vgic_present)
1842 return -ENXIO;
1843 return kvm_set_legacy_vgic_v2_addr(kvm, dev_addr);
1844 default:
1845 return -ENODEV;
1846 }
1847 }
1848
kvm_vm_has_attr(struct kvm * kvm,struct kvm_device_attr * attr)1849 static int kvm_vm_has_attr(struct kvm *kvm, struct kvm_device_attr *attr)
1850 {
1851 switch (attr->group) {
1852 case KVM_ARM_VM_SMCCC_CTRL:
1853 return kvm_vm_smccc_has_attr(kvm, attr);
1854 default:
1855 return -ENXIO;
1856 }
1857 }
1858
kvm_vm_set_attr(struct kvm * kvm,struct kvm_device_attr * attr)1859 static int kvm_vm_set_attr(struct kvm *kvm, struct kvm_device_attr *attr)
1860 {
1861 switch (attr->group) {
1862 case KVM_ARM_VM_SMCCC_CTRL:
1863 return kvm_vm_smccc_set_attr(kvm, attr);
1864 default:
1865 return -ENXIO;
1866 }
1867 }
1868
kvm_arch_vm_ioctl(struct file * filp,unsigned int ioctl,unsigned long arg)1869 int kvm_arch_vm_ioctl(struct file *filp, unsigned int ioctl, unsigned long arg)
1870 {
1871 struct kvm *kvm = filp->private_data;
1872 void __user *argp = (void __user *)arg;
1873 struct kvm_device_attr attr;
1874
1875 switch (ioctl) {
1876 case KVM_CREATE_IRQCHIP: {
1877 int ret;
1878 if (!vgic_present)
1879 return -ENXIO;
1880 mutex_lock(&kvm->lock);
1881 ret = kvm_vgic_create(kvm, KVM_DEV_TYPE_ARM_VGIC_V2);
1882 mutex_unlock(&kvm->lock);
1883 return ret;
1884 }
1885 case KVM_ARM_SET_DEVICE_ADDR: {
1886 struct kvm_arm_device_addr dev_addr;
1887
1888 if (copy_from_user(&dev_addr, argp, sizeof(dev_addr)))
1889 return -EFAULT;
1890 return kvm_vm_ioctl_set_device_addr(kvm, &dev_addr);
1891 }
1892 case KVM_ARM_PREFERRED_TARGET: {
1893 struct kvm_vcpu_init init = {
1894 .target = KVM_ARM_TARGET_GENERIC_V8,
1895 };
1896
1897 if (copy_to_user(argp, &init, sizeof(init)))
1898 return -EFAULT;
1899
1900 return 0;
1901 }
1902 case KVM_ARM_MTE_COPY_TAGS: {
1903 struct kvm_arm_copy_mte_tags copy_tags;
1904
1905 if (copy_from_user(©_tags, argp, sizeof(copy_tags)))
1906 return -EFAULT;
1907 return kvm_vm_ioctl_mte_copy_tags(kvm, ©_tags);
1908 }
1909 case KVM_ARM_SET_COUNTER_OFFSET: {
1910 struct kvm_arm_counter_offset offset;
1911
1912 if (copy_from_user(&offset, argp, sizeof(offset)))
1913 return -EFAULT;
1914 return kvm_vm_ioctl_set_counter_offset(kvm, &offset);
1915 }
1916 case KVM_HAS_DEVICE_ATTR: {
1917 if (copy_from_user(&attr, argp, sizeof(attr)))
1918 return -EFAULT;
1919
1920 return kvm_vm_has_attr(kvm, &attr);
1921 }
1922 case KVM_SET_DEVICE_ATTR: {
1923 if (copy_from_user(&attr, argp, sizeof(attr)))
1924 return -EFAULT;
1925
1926 return kvm_vm_set_attr(kvm, &attr);
1927 }
1928 case KVM_ARM_GET_REG_WRITABLE_MASKS: {
1929 struct reg_mask_range range;
1930
1931 if (copy_from_user(&range, argp, sizeof(range)))
1932 return -EFAULT;
1933 return kvm_vm_ioctl_get_reg_writable_masks(kvm, &range);
1934 }
1935 default:
1936 return -EINVAL;
1937 }
1938 }
1939
nvhe_percpu_size(void)1940 static unsigned long nvhe_percpu_size(void)
1941 {
1942 return (unsigned long)CHOOSE_NVHE_SYM(__per_cpu_end) -
1943 (unsigned long)CHOOSE_NVHE_SYM(__per_cpu_start);
1944 }
1945
nvhe_percpu_order(void)1946 static unsigned long nvhe_percpu_order(void)
1947 {
1948 unsigned long size = nvhe_percpu_size();
1949
1950 return size ? get_order(size) : 0;
1951 }
1952
pkvm_host_sve_state_order(void)1953 static size_t pkvm_host_sve_state_order(void)
1954 {
1955 return get_order(pkvm_host_sve_state_size());
1956 }
1957
1958 /* A lookup table holding the hypervisor VA for each vector slot */
1959 static void *hyp_spectre_vector_selector[BP_HARDEN_EL2_SLOTS];
1960
kvm_init_vector_slot(void * base,enum arm64_hyp_spectre_vector slot)1961 static void kvm_init_vector_slot(void *base, enum arm64_hyp_spectre_vector slot)
1962 {
1963 hyp_spectre_vector_selector[slot] = __kvm_vector_slot2addr(base, slot);
1964 }
1965
kvm_init_vector_slots(void)1966 static int kvm_init_vector_slots(void)
1967 {
1968 int err;
1969 void *base;
1970
1971 base = kern_hyp_va(kvm_ksym_ref(__kvm_hyp_vector));
1972 kvm_init_vector_slot(base, HYP_VECTOR_DIRECT);
1973
1974 base = kern_hyp_va(kvm_ksym_ref(__bp_harden_hyp_vecs));
1975 kvm_init_vector_slot(base, HYP_VECTOR_SPECTRE_DIRECT);
1976
1977 if (kvm_system_needs_idmapped_vectors() &&
1978 !is_protected_kvm_enabled()) {
1979 err = create_hyp_exec_mappings(__pa_symbol(__bp_harden_hyp_vecs),
1980 __BP_HARDEN_HYP_VECS_SZ, &base);
1981 if (err)
1982 return err;
1983 }
1984
1985 kvm_init_vector_slot(base, HYP_VECTOR_INDIRECT);
1986 kvm_init_vector_slot(base, HYP_VECTOR_SPECTRE_INDIRECT);
1987 return 0;
1988 }
1989
cpu_prepare_hyp_mode(int cpu,u32 hyp_va_bits)1990 static void __init cpu_prepare_hyp_mode(int cpu, u32 hyp_va_bits)
1991 {
1992 struct kvm_nvhe_init_params *params = per_cpu_ptr_nvhe_sym(kvm_init_params, cpu);
1993 unsigned long tcr;
1994
1995 /*
1996 * Calculate the raw per-cpu offset without a translation from the
1997 * kernel's mapping to the linear mapping, and store it in tpidr_el2
1998 * so that we can use adr_l to access per-cpu variables in EL2.
1999 * Also drop the KASAN tag which gets in the way...
2000 */
2001 params->tpidr_el2 = (unsigned long)kasan_reset_tag(per_cpu_ptr_nvhe_sym(__per_cpu_start, cpu)) -
2002 (unsigned long)kvm_ksym_ref(CHOOSE_NVHE_SYM(__per_cpu_start));
2003
2004 params->mair_el2 = read_sysreg(mair_el1);
2005
2006 tcr = read_sysreg(tcr_el1);
2007 if (cpus_have_final_cap(ARM64_KVM_HVHE)) {
2008 tcr &= ~(TCR_HD | TCR_HA | TCR_A1 | TCR_T0SZ_MASK);
2009 tcr |= TCR_EPD1_MASK;
2010 } else {
2011 unsigned long ips = FIELD_GET(TCR_IPS_MASK, tcr);
2012
2013 tcr &= TCR_EL2_MASK;
2014 tcr |= TCR_EL2_RES1 | FIELD_PREP(TCR_EL2_PS_MASK, ips);
2015 if (lpa2_is_enabled())
2016 tcr |= TCR_EL2_DS;
2017 }
2018 tcr |= TCR_T0SZ(hyp_va_bits);
2019 params->tcr_el2 = tcr;
2020
2021 params->pgd_pa = kvm_mmu_get_httbr();
2022 if (is_protected_kvm_enabled())
2023 params->hcr_el2 = HCR_HOST_NVHE_PROTECTED_FLAGS;
2024 else
2025 params->hcr_el2 = HCR_HOST_NVHE_FLAGS;
2026 if (cpus_have_final_cap(ARM64_KVM_HVHE))
2027 params->hcr_el2 |= HCR_E2H;
2028 params->vttbr = params->vtcr = 0;
2029
2030 /*
2031 * Flush the init params from the data cache because the struct will
2032 * be read while the MMU is off.
2033 */
2034 kvm_flush_dcache_to_poc(params, sizeof(*params));
2035 }
2036
hyp_install_host_vector(void)2037 static void hyp_install_host_vector(void)
2038 {
2039 struct kvm_nvhe_init_params *params;
2040 struct arm_smccc_res res;
2041
2042 /* Switch from the HYP stub to our own HYP init vector */
2043 __hyp_set_vectors(kvm_get_idmap_vector());
2044
2045 /*
2046 * Call initialization code, and switch to the full blown HYP code.
2047 * If the cpucaps haven't been finalized yet, something has gone very
2048 * wrong, and hyp will crash and burn when it uses any
2049 * cpus_have_*_cap() wrapper.
2050 */
2051 BUG_ON(!system_capabilities_finalized());
2052 params = this_cpu_ptr_nvhe_sym(kvm_init_params);
2053 arm_smccc_1_1_hvc(KVM_HOST_SMCCC_FUNC(__kvm_hyp_init), virt_to_phys(params), &res);
2054 WARN_ON(res.a0 != SMCCC_RET_SUCCESS);
2055 }
2056
cpu_init_hyp_mode(void)2057 static void cpu_init_hyp_mode(void)
2058 {
2059 hyp_install_host_vector();
2060
2061 /*
2062 * Disabling SSBD on a non-VHE system requires us to enable SSBS
2063 * at EL2.
2064 */
2065 if (this_cpu_has_cap(ARM64_SSBS) &&
2066 arm64_get_spectre_v4_state() == SPECTRE_VULNERABLE) {
2067 kvm_call_hyp_nvhe(__kvm_enable_ssbs);
2068 }
2069 }
2070
cpu_hyp_reset(void)2071 static void cpu_hyp_reset(void)
2072 {
2073 if (!is_kernel_in_hyp_mode())
2074 __hyp_reset_vectors();
2075 }
2076
2077 /*
2078 * EL2 vectors can be mapped and rerouted in a number of ways,
2079 * depending on the kernel configuration and CPU present:
2080 *
2081 * - If the CPU is affected by Spectre-v2, the hardening sequence is
2082 * placed in one of the vector slots, which is executed before jumping
2083 * to the real vectors.
2084 *
2085 * - If the CPU also has the ARM64_SPECTRE_V3A cap, the slot
2086 * containing the hardening sequence is mapped next to the idmap page,
2087 * and executed before jumping to the real vectors.
2088 *
2089 * - If the CPU only has the ARM64_SPECTRE_V3A cap, then an
2090 * empty slot is selected, mapped next to the idmap page, and
2091 * executed before jumping to the real vectors.
2092 *
2093 * Note that ARM64_SPECTRE_V3A is somewhat incompatible with
2094 * VHE, as we don't have hypervisor-specific mappings. If the system
2095 * is VHE and yet selects this capability, it will be ignored.
2096 */
cpu_set_hyp_vector(void)2097 static void cpu_set_hyp_vector(void)
2098 {
2099 struct bp_hardening_data *data = this_cpu_ptr(&bp_hardening_data);
2100 void *vector = hyp_spectre_vector_selector[data->slot];
2101
2102 if (!is_protected_kvm_enabled())
2103 *this_cpu_ptr_hyp_sym(kvm_hyp_vector) = (unsigned long)vector;
2104 else
2105 kvm_call_hyp_nvhe(__pkvm_cpu_set_vector, data->slot);
2106 }
2107
cpu_hyp_init_context(void)2108 static void cpu_hyp_init_context(void)
2109 {
2110 kvm_init_host_cpu_context(host_data_ptr(host_ctxt));
2111 kvm_init_host_debug_data();
2112
2113 if (!is_kernel_in_hyp_mode())
2114 cpu_init_hyp_mode();
2115 }
2116
cpu_hyp_init_features(void)2117 static void cpu_hyp_init_features(void)
2118 {
2119 cpu_set_hyp_vector();
2120
2121 if (is_kernel_in_hyp_mode()) {
2122 kvm_timer_init_vhe();
2123 kvm_debug_init_vhe();
2124 }
2125
2126 if (vgic_present)
2127 kvm_vgic_init_cpu_hardware();
2128 }
2129
cpu_hyp_reinit(void)2130 static void cpu_hyp_reinit(void)
2131 {
2132 cpu_hyp_reset();
2133 cpu_hyp_init_context();
2134 cpu_hyp_init_features();
2135 }
2136
cpu_hyp_init(void * discard)2137 static void cpu_hyp_init(void *discard)
2138 {
2139 if (!__this_cpu_read(kvm_hyp_initialized)) {
2140 cpu_hyp_reinit();
2141 __this_cpu_write(kvm_hyp_initialized, 1);
2142 }
2143 }
2144
cpu_hyp_uninit(void * discard)2145 static void cpu_hyp_uninit(void *discard)
2146 {
2147 if (!is_protected_kvm_enabled() && __this_cpu_read(kvm_hyp_initialized)) {
2148 cpu_hyp_reset();
2149 __this_cpu_write(kvm_hyp_initialized, 0);
2150 }
2151 }
2152
kvm_arch_enable_virtualization_cpu(void)2153 int kvm_arch_enable_virtualization_cpu(void)
2154 {
2155 /*
2156 * Most calls to this function are made with migration
2157 * disabled, but not with preemption disabled. The former is
2158 * enough to ensure correctness, but most of the helpers
2159 * expect the later and will throw a tantrum otherwise.
2160 */
2161 preempt_disable();
2162
2163 cpu_hyp_init(NULL);
2164
2165 kvm_vgic_cpu_up();
2166 kvm_timer_cpu_up();
2167
2168 preempt_enable();
2169
2170 return 0;
2171 }
2172
kvm_arch_disable_virtualization_cpu(void)2173 void kvm_arch_disable_virtualization_cpu(void)
2174 {
2175 kvm_timer_cpu_down();
2176 kvm_vgic_cpu_down();
2177
2178 if (!is_protected_kvm_enabled())
2179 cpu_hyp_uninit(NULL);
2180 }
2181
2182 #ifdef CONFIG_CPU_PM
hyp_init_cpu_pm_notifier(struct notifier_block * self,unsigned long cmd,void * v)2183 static int hyp_init_cpu_pm_notifier(struct notifier_block *self,
2184 unsigned long cmd,
2185 void *v)
2186 {
2187 /*
2188 * kvm_hyp_initialized is left with its old value over
2189 * PM_ENTER->PM_EXIT. It is used to indicate PM_EXIT should
2190 * re-enable hyp.
2191 */
2192 switch (cmd) {
2193 case CPU_PM_ENTER:
2194 if (__this_cpu_read(kvm_hyp_initialized))
2195 /*
2196 * don't update kvm_hyp_initialized here
2197 * so that the hyp will be re-enabled
2198 * when we resume. See below.
2199 */
2200 cpu_hyp_reset();
2201
2202 return NOTIFY_OK;
2203 case CPU_PM_ENTER_FAILED:
2204 case CPU_PM_EXIT:
2205 if (__this_cpu_read(kvm_hyp_initialized))
2206 /* The hyp was enabled before suspend. */
2207 cpu_hyp_reinit();
2208
2209 return NOTIFY_OK;
2210
2211 default:
2212 return NOTIFY_DONE;
2213 }
2214 }
2215
2216 static struct notifier_block hyp_init_cpu_pm_nb = {
2217 .notifier_call = hyp_init_cpu_pm_notifier,
2218 };
2219
hyp_cpu_pm_init(void)2220 static void __init hyp_cpu_pm_init(void)
2221 {
2222 if (!is_protected_kvm_enabled())
2223 cpu_pm_register_notifier(&hyp_init_cpu_pm_nb);
2224 }
hyp_cpu_pm_exit(void)2225 static void __init hyp_cpu_pm_exit(void)
2226 {
2227 if (!is_protected_kvm_enabled())
2228 cpu_pm_unregister_notifier(&hyp_init_cpu_pm_nb);
2229 }
2230 #else
hyp_cpu_pm_init(void)2231 static inline void __init hyp_cpu_pm_init(void)
2232 {
2233 }
hyp_cpu_pm_exit(void)2234 static inline void __init hyp_cpu_pm_exit(void)
2235 {
2236 }
2237 #endif
2238
init_cpu_logical_map(void)2239 static void __init init_cpu_logical_map(void)
2240 {
2241 unsigned int cpu;
2242
2243 /*
2244 * Copy the MPIDR <-> logical CPU ID mapping to hyp.
2245 * Only copy the set of online CPUs whose features have been checked
2246 * against the finalized system capabilities. The hypervisor will not
2247 * allow any other CPUs from the `possible` set to boot.
2248 */
2249 for_each_online_cpu(cpu)
2250 hyp_cpu_logical_map[cpu] = cpu_logical_map(cpu);
2251 }
2252
2253 #define init_psci_0_1_impl_state(config, what) \
2254 config.psci_0_1_ ## what ## _implemented = psci_ops.what
2255
init_psci_relay(void)2256 static bool __init init_psci_relay(void)
2257 {
2258 /*
2259 * If PSCI has not been initialized, protected KVM cannot install
2260 * itself on newly booted CPUs.
2261 */
2262 if (!psci_ops.get_version) {
2263 kvm_err("Cannot initialize protected mode without PSCI\n");
2264 return false;
2265 }
2266
2267 kvm_host_psci_config.version = psci_ops.get_version();
2268 kvm_host_psci_config.smccc_version = arm_smccc_get_version();
2269
2270 if (kvm_host_psci_config.version == PSCI_VERSION(0, 1)) {
2271 kvm_host_psci_config.function_ids_0_1 = get_psci_0_1_function_ids();
2272 init_psci_0_1_impl_state(kvm_host_psci_config, cpu_suspend);
2273 init_psci_0_1_impl_state(kvm_host_psci_config, cpu_on);
2274 init_psci_0_1_impl_state(kvm_host_psci_config, cpu_off);
2275 init_psci_0_1_impl_state(kvm_host_psci_config, migrate);
2276 }
2277 return true;
2278 }
2279
init_subsystems(void)2280 static int __init init_subsystems(void)
2281 {
2282 int err = 0;
2283
2284 /*
2285 * Enable hardware so that subsystem initialisation can access EL2.
2286 */
2287 on_each_cpu(cpu_hyp_init, NULL, 1);
2288
2289 /*
2290 * Register CPU lower-power notifier
2291 */
2292 hyp_cpu_pm_init();
2293
2294 /*
2295 * Init HYP view of VGIC
2296 */
2297 err = kvm_vgic_hyp_init();
2298 switch (err) {
2299 case 0:
2300 vgic_present = true;
2301 break;
2302 case -ENODEV:
2303 case -ENXIO:
2304 /*
2305 * No VGIC? No pKVM for you.
2306 *
2307 * Protected mode assumes that VGICv3 is present, so no point
2308 * in trying to hobble along if vgic initialization fails.
2309 */
2310 if (is_protected_kvm_enabled())
2311 goto out;
2312
2313 /*
2314 * Otherwise, userspace could choose to implement a GIC for its
2315 * guest on non-cooperative hardware.
2316 */
2317 vgic_present = false;
2318 err = 0;
2319 break;
2320 default:
2321 goto out;
2322 }
2323
2324 if (kvm_mode == KVM_MODE_NV &&
2325 !(vgic_present && (kvm_vgic_global_state.type == VGIC_V3 ||
2326 kvm_vgic_global_state.has_gcie_v3_compat))) {
2327 kvm_err("NV support requires GICv3 or GICv5 with legacy support, giving up\n");
2328 err = -EINVAL;
2329 goto out;
2330 }
2331
2332 /*
2333 * Init HYP architected timer support
2334 */
2335 err = kvm_timer_hyp_init(vgic_present);
2336 if (err)
2337 goto out;
2338
2339 kvm_register_perf_callbacks(NULL);
2340
2341 out:
2342 if (err)
2343 hyp_cpu_pm_exit();
2344
2345 if (err || !is_protected_kvm_enabled())
2346 on_each_cpu(cpu_hyp_uninit, NULL, 1);
2347
2348 return err;
2349 }
2350
teardown_subsystems(void)2351 static void __init teardown_subsystems(void)
2352 {
2353 kvm_unregister_perf_callbacks();
2354 hyp_cpu_pm_exit();
2355 }
2356
teardown_hyp_mode(void)2357 static void __init teardown_hyp_mode(void)
2358 {
2359 bool free_sve = system_supports_sve() && is_protected_kvm_enabled();
2360 int cpu;
2361
2362 free_hyp_pgds();
2363 for_each_possible_cpu(cpu) {
2364 if (per_cpu(kvm_hyp_initialized, cpu))
2365 continue;
2366
2367 free_pages(per_cpu(kvm_arm_hyp_stack_base, cpu), NVHE_STACK_SHIFT - PAGE_SHIFT);
2368
2369 if (!kvm_nvhe_sym(kvm_arm_hyp_percpu_base)[cpu])
2370 continue;
2371
2372 if (free_sve) {
2373 struct cpu_sve_state *sve_state;
2374
2375 sve_state = per_cpu_ptr_nvhe_sym(kvm_host_data, cpu)->sve_state;
2376 free_pages((unsigned long) sve_state, pkvm_host_sve_state_order());
2377 }
2378
2379 free_pages(kvm_nvhe_sym(kvm_arm_hyp_percpu_base)[cpu], nvhe_percpu_order());
2380
2381 }
2382 }
2383
do_pkvm_init(u32 hyp_va_bits)2384 static int __init do_pkvm_init(u32 hyp_va_bits)
2385 {
2386 void *per_cpu_base = kvm_ksym_ref(kvm_nvhe_sym(kvm_arm_hyp_percpu_base));
2387 int ret;
2388
2389 preempt_disable();
2390 cpu_hyp_init_context();
2391 ret = kvm_call_hyp_nvhe(__pkvm_init, hyp_mem_base, hyp_mem_size,
2392 num_possible_cpus(), kern_hyp_va(per_cpu_base),
2393 hyp_va_bits);
2394 cpu_hyp_init_features();
2395
2396 /*
2397 * The stub hypercalls are now disabled, so set our local flag to
2398 * prevent a later re-init attempt in kvm_arch_enable_virtualization_cpu().
2399 */
2400 __this_cpu_write(kvm_hyp_initialized, 1);
2401 preempt_enable();
2402
2403 return ret;
2404 }
2405
get_hyp_id_aa64pfr0_el1(void)2406 static u64 get_hyp_id_aa64pfr0_el1(void)
2407 {
2408 /*
2409 * Track whether the system isn't affected by spectre/meltdown in the
2410 * hypervisor's view of id_aa64pfr0_el1, used for protected VMs.
2411 * Although this is per-CPU, we make it global for simplicity, e.g., not
2412 * to have to worry about vcpu migration.
2413 *
2414 * Unlike for non-protected VMs, userspace cannot override this for
2415 * protected VMs.
2416 */
2417 u64 val = read_sanitised_ftr_reg(SYS_ID_AA64PFR0_EL1);
2418
2419 val &= ~(ID_AA64PFR0_EL1_CSV2 |
2420 ID_AA64PFR0_EL1_CSV3);
2421
2422 val |= FIELD_PREP(ID_AA64PFR0_EL1_CSV2,
2423 arm64_get_spectre_v2_state() == SPECTRE_UNAFFECTED);
2424 val |= FIELD_PREP(ID_AA64PFR0_EL1_CSV3,
2425 arm64_get_meltdown_state() == SPECTRE_UNAFFECTED);
2426
2427 return val;
2428 }
2429
kvm_hyp_init_symbols(void)2430 static void kvm_hyp_init_symbols(void)
2431 {
2432 kvm_nvhe_sym(id_aa64pfr0_el1_sys_val) = get_hyp_id_aa64pfr0_el1();
2433 kvm_nvhe_sym(id_aa64pfr1_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64PFR1_EL1);
2434 kvm_nvhe_sym(id_aa64isar0_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64ISAR0_EL1);
2435 kvm_nvhe_sym(id_aa64isar1_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64ISAR1_EL1);
2436 kvm_nvhe_sym(id_aa64isar2_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64ISAR2_EL1);
2437 kvm_nvhe_sym(id_aa64mmfr0_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64MMFR0_EL1);
2438 kvm_nvhe_sym(id_aa64mmfr1_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64MMFR1_EL1);
2439 kvm_nvhe_sym(id_aa64mmfr2_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64MMFR2_EL1);
2440 kvm_nvhe_sym(id_aa64smfr0_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64SMFR0_EL1);
2441 kvm_nvhe_sym(__icache_flags) = __icache_flags;
2442 kvm_nvhe_sym(kvm_arm_vmid_bits) = kvm_arm_vmid_bits;
2443
2444 /* Propagate the FGT state to the the nVHE side */
2445 kvm_nvhe_sym(hfgrtr_masks) = hfgrtr_masks;
2446 kvm_nvhe_sym(hfgwtr_masks) = hfgwtr_masks;
2447 kvm_nvhe_sym(hfgitr_masks) = hfgitr_masks;
2448 kvm_nvhe_sym(hdfgrtr_masks) = hdfgrtr_masks;
2449 kvm_nvhe_sym(hdfgwtr_masks) = hdfgwtr_masks;
2450 kvm_nvhe_sym(hafgrtr_masks) = hafgrtr_masks;
2451 kvm_nvhe_sym(hfgrtr2_masks) = hfgrtr2_masks;
2452 kvm_nvhe_sym(hfgwtr2_masks) = hfgwtr2_masks;
2453 kvm_nvhe_sym(hfgitr2_masks) = hfgitr2_masks;
2454 kvm_nvhe_sym(hdfgrtr2_masks)= hdfgrtr2_masks;
2455 kvm_nvhe_sym(hdfgwtr2_masks)= hdfgwtr2_masks;
2456
2457 /*
2458 * Flush entire BSS since part of its data containing init symbols is read
2459 * while the MMU is off.
2460 */
2461 kvm_flush_dcache_to_poc(kvm_ksym_ref(__hyp_bss_start),
2462 kvm_ksym_ref(__hyp_bss_end) - kvm_ksym_ref(__hyp_bss_start));
2463 }
2464
kvm_hyp_init_protection(u32 hyp_va_bits)2465 static int __init kvm_hyp_init_protection(u32 hyp_va_bits)
2466 {
2467 void *addr = phys_to_virt(hyp_mem_base);
2468 int ret;
2469
2470 ret = create_hyp_mappings(addr, addr + hyp_mem_size, PAGE_HYP);
2471 if (ret)
2472 return ret;
2473
2474 ret = do_pkvm_init(hyp_va_bits);
2475 if (ret)
2476 return ret;
2477
2478 free_hyp_pgds();
2479
2480 return 0;
2481 }
2482
init_pkvm_host_sve_state(void)2483 static int init_pkvm_host_sve_state(void)
2484 {
2485 int cpu;
2486
2487 if (!system_supports_sve())
2488 return 0;
2489
2490 /* Allocate pages for host sve state in protected mode. */
2491 for_each_possible_cpu(cpu) {
2492 struct page *page = alloc_pages(GFP_KERNEL, pkvm_host_sve_state_order());
2493
2494 if (!page)
2495 return -ENOMEM;
2496
2497 per_cpu_ptr_nvhe_sym(kvm_host_data, cpu)->sve_state = page_address(page);
2498 }
2499
2500 /*
2501 * Don't map the pages in hyp since these are only used in protected
2502 * mode, which will (re)create its own mapping when initialized.
2503 */
2504
2505 return 0;
2506 }
2507
2508 /*
2509 * Finalizes the initialization of hyp mode, once everything else is initialized
2510 * and the initialziation process cannot fail.
2511 */
finalize_init_hyp_mode(void)2512 static void finalize_init_hyp_mode(void)
2513 {
2514 int cpu;
2515
2516 if (system_supports_sve() && is_protected_kvm_enabled()) {
2517 for_each_possible_cpu(cpu) {
2518 struct cpu_sve_state *sve_state;
2519
2520 sve_state = per_cpu_ptr_nvhe_sym(kvm_host_data, cpu)->sve_state;
2521 per_cpu_ptr_nvhe_sym(kvm_host_data, cpu)->sve_state =
2522 kern_hyp_va(sve_state);
2523 }
2524 }
2525 }
2526
pkvm_hyp_init_ptrauth(void)2527 static void pkvm_hyp_init_ptrauth(void)
2528 {
2529 struct kvm_cpu_context *hyp_ctxt;
2530 int cpu;
2531
2532 for_each_possible_cpu(cpu) {
2533 hyp_ctxt = per_cpu_ptr_nvhe_sym(kvm_hyp_ctxt, cpu);
2534 hyp_ctxt->sys_regs[APIAKEYLO_EL1] = get_random_long();
2535 hyp_ctxt->sys_regs[APIAKEYHI_EL1] = get_random_long();
2536 hyp_ctxt->sys_regs[APIBKEYLO_EL1] = get_random_long();
2537 hyp_ctxt->sys_regs[APIBKEYHI_EL1] = get_random_long();
2538 hyp_ctxt->sys_regs[APDAKEYLO_EL1] = get_random_long();
2539 hyp_ctxt->sys_regs[APDAKEYHI_EL1] = get_random_long();
2540 hyp_ctxt->sys_regs[APDBKEYLO_EL1] = get_random_long();
2541 hyp_ctxt->sys_regs[APDBKEYHI_EL1] = get_random_long();
2542 hyp_ctxt->sys_regs[APGAKEYLO_EL1] = get_random_long();
2543 hyp_ctxt->sys_regs[APGAKEYHI_EL1] = get_random_long();
2544 }
2545 }
2546
2547 /* Inits Hyp-mode on all online CPUs */
init_hyp_mode(void)2548 static int __init init_hyp_mode(void)
2549 {
2550 u32 hyp_va_bits;
2551 int cpu;
2552 int err = -ENOMEM;
2553
2554 /*
2555 * The protected Hyp-mode cannot be initialized if the memory pool
2556 * allocation has failed.
2557 */
2558 if (is_protected_kvm_enabled() && !hyp_mem_base)
2559 goto out_err;
2560
2561 /*
2562 * Allocate Hyp PGD and setup Hyp identity mapping
2563 */
2564 err = kvm_mmu_init(&hyp_va_bits);
2565 if (err)
2566 goto out_err;
2567
2568 /*
2569 * Allocate stack pages for Hypervisor-mode
2570 */
2571 for_each_possible_cpu(cpu) {
2572 unsigned long stack_base;
2573
2574 stack_base = __get_free_pages(GFP_KERNEL, NVHE_STACK_SHIFT - PAGE_SHIFT);
2575 if (!stack_base) {
2576 err = -ENOMEM;
2577 goto out_err;
2578 }
2579
2580 per_cpu(kvm_arm_hyp_stack_base, cpu) = stack_base;
2581 }
2582
2583 /*
2584 * Allocate and initialize pages for Hypervisor-mode percpu regions.
2585 */
2586 for_each_possible_cpu(cpu) {
2587 struct page *page;
2588 void *page_addr;
2589
2590 page = alloc_pages(GFP_KERNEL, nvhe_percpu_order());
2591 if (!page) {
2592 err = -ENOMEM;
2593 goto out_err;
2594 }
2595
2596 page_addr = page_address(page);
2597 memcpy(page_addr, CHOOSE_NVHE_SYM(__per_cpu_start), nvhe_percpu_size());
2598 kvm_nvhe_sym(kvm_arm_hyp_percpu_base)[cpu] = (unsigned long)page_addr;
2599 }
2600
2601 /*
2602 * Map the Hyp-code called directly from the host
2603 */
2604 err = create_hyp_mappings(kvm_ksym_ref(__hyp_text_start),
2605 kvm_ksym_ref(__hyp_text_end), PAGE_HYP_EXEC);
2606 if (err) {
2607 kvm_err("Cannot map world-switch code\n");
2608 goto out_err;
2609 }
2610
2611 err = create_hyp_mappings(kvm_ksym_ref(__hyp_data_start),
2612 kvm_ksym_ref(__hyp_data_end), PAGE_HYP);
2613 if (err) {
2614 kvm_err("Cannot map .hyp.data section\n");
2615 goto out_err;
2616 }
2617
2618 err = create_hyp_mappings(kvm_ksym_ref(__hyp_rodata_start),
2619 kvm_ksym_ref(__hyp_rodata_end), PAGE_HYP_RO);
2620 if (err) {
2621 kvm_err("Cannot map .hyp.rodata section\n");
2622 goto out_err;
2623 }
2624
2625 err = create_hyp_mappings(kvm_ksym_ref(__start_rodata),
2626 kvm_ksym_ref(__end_rodata), PAGE_HYP_RO);
2627 if (err) {
2628 kvm_err("Cannot map rodata section\n");
2629 goto out_err;
2630 }
2631
2632 /*
2633 * .hyp.bss is guaranteed to be placed at the beginning of the .bss
2634 * section thanks to an assertion in the linker script. Map it RW and
2635 * the rest of .bss RO.
2636 */
2637 err = create_hyp_mappings(kvm_ksym_ref(__hyp_bss_start),
2638 kvm_ksym_ref(__hyp_bss_end), PAGE_HYP);
2639 if (err) {
2640 kvm_err("Cannot map hyp bss section: %d\n", err);
2641 goto out_err;
2642 }
2643
2644 err = create_hyp_mappings(kvm_ksym_ref(__hyp_bss_end),
2645 kvm_ksym_ref(__bss_stop), PAGE_HYP_RO);
2646 if (err) {
2647 kvm_err("Cannot map bss section\n");
2648 goto out_err;
2649 }
2650
2651 /*
2652 * Map the Hyp stack pages
2653 */
2654 for_each_possible_cpu(cpu) {
2655 struct kvm_nvhe_init_params *params = per_cpu_ptr_nvhe_sym(kvm_init_params, cpu);
2656 char *stack_base = (char *)per_cpu(kvm_arm_hyp_stack_base, cpu);
2657
2658 err = create_hyp_stack(__pa(stack_base), ¶ms->stack_hyp_va);
2659 if (err) {
2660 kvm_err("Cannot map hyp stack\n");
2661 goto out_err;
2662 }
2663
2664 /*
2665 * Save the stack PA in nvhe_init_params. This will be needed
2666 * to recreate the stack mapping in protected nVHE mode.
2667 * __hyp_pa() won't do the right thing there, since the stack
2668 * has been mapped in the flexible private VA space.
2669 */
2670 params->stack_pa = __pa(stack_base);
2671 }
2672
2673 for_each_possible_cpu(cpu) {
2674 char *percpu_begin = (char *)kvm_nvhe_sym(kvm_arm_hyp_percpu_base)[cpu];
2675 char *percpu_end = percpu_begin + nvhe_percpu_size();
2676
2677 /* Map Hyp percpu pages */
2678 err = create_hyp_mappings(percpu_begin, percpu_end, PAGE_HYP);
2679 if (err) {
2680 kvm_err("Cannot map hyp percpu region\n");
2681 goto out_err;
2682 }
2683
2684 /* Prepare the CPU initialization parameters */
2685 cpu_prepare_hyp_mode(cpu, hyp_va_bits);
2686 }
2687
2688 kvm_hyp_init_symbols();
2689
2690 if (is_protected_kvm_enabled()) {
2691 if (IS_ENABLED(CONFIG_ARM64_PTR_AUTH_KERNEL) &&
2692 cpus_have_final_cap(ARM64_HAS_ADDRESS_AUTH))
2693 pkvm_hyp_init_ptrauth();
2694
2695 init_cpu_logical_map();
2696
2697 if (!init_psci_relay()) {
2698 err = -ENODEV;
2699 goto out_err;
2700 }
2701
2702 err = init_pkvm_host_sve_state();
2703 if (err)
2704 goto out_err;
2705
2706 err = kvm_hyp_init_protection(hyp_va_bits);
2707 if (err) {
2708 kvm_err("Failed to init hyp memory protection\n");
2709 goto out_err;
2710 }
2711 }
2712
2713 return 0;
2714
2715 out_err:
2716 teardown_hyp_mode();
2717 kvm_err("error initializing Hyp mode: %d\n", err);
2718 return err;
2719 }
2720
kvm_mpidr_to_vcpu(struct kvm * kvm,unsigned long mpidr)2721 struct kvm_vcpu *kvm_mpidr_to_vcpu(struct kvm *kvm, unsigned long mpidr)
2722 {
2723 struct kvm_vcpu *vcpu = NULL;
2724 struct kvm_mpidr_data *data;
2725 unsigned long i;
2726
2727 mpidr &= MPIDR_HWID_BITMASK;
2728
2729 rcu_read_lock();
2730 data = rcu_dereference(kvm->arch.mpidr_data);
2731
2732 if (data) {
2733 u16 idx = kvm_mpidr_index(data, mpidr);
2734
2735 vcpu = kvm_get_vcpu(kvm, data->cmpidr_to_idx[idx]);
2736 if (mpidr != kvm_vcpu_get_mpidr_aff(vcpu))
2737 vcpu = NULL;
2738 }
2739
2740 rcu_read_unlock();
2741
2742 if (vcpu)
2743 return vcpu;
2744
2745 kvm_for_each_vcpu(i, vcpu, kvm) {
2746 if (mpidr == kvm_vcpu_get_mpidr_aff(vcpu))
2747 return vcpu;
2748 }
2749 return NULL;
2750 }
2751
kvm_arch_irqchip_in_kernel(struct kvm * kvm)2752 bool kvm_arch_irqchip_in_kernel(struct kvm *kvm)
2753 {
2754 return irqchip_in_kernel(kvm);
2755 }
2756
kvm_arch_irq_bypass_add_producer(struct irq_bypass_consumer * cons,struct irq_bypass_producer * prod)2757 int kvm_arch_irq_bypass_add_producer(struct irq_bypass_consumer *cons,
2758 struct irq_bypass_producer *prod)
2759 {
2760 struct kvm_kernel_irqfd *irqfd =
2761 container_of(cons, struct kvm_kernel_irqfd, consumer);
2762 struct kvm_kernel_irq_routing_entry *irq_entry = &irqfd->irq_entry;
2763
2764 /*
2765 * The only thing we have a chance of directly-injecting is LPIs. Maybe
2766 * one day...
2767 */
2768 if (irq_entry->type != KVM_IRQ_ROUTING_MSI)
2769 return 0;
2770
2771 return kvm_vgic_v4_set_forwarding(irqfd->kvm, prod->irq,
2772 &irqfd->irq_entry);
2773 }
2774
kvm_arch_irq_bypass_del_producer(struct irq_bypass_consumer * cons,struct irq_bypass_producer * prod)2775 void kvm_arch_irq_bypass_del_producer(struct irq_bypass_consumer *cons,
2776 struct irq_bypass_producer *prod)
2777 {
2778 struct kvm_kernel_irqfd *irqfd =
2779 container_of(cons, struct kvm_kernel_irqfd, consumer);
2780 struct kvm_kernel_irq_routing_entry *irq_entry = &irqfd->irq_entry;
2781
2782 if (irq_entry->type != KVM_IRQ_ROUTING_MSI)
2783 return;
2784
2785 kvm_vgic_v4_unset_forwarding(irqfd->kvm, prod->irq);
2786 }
2787
kvm_arch_update_irqfd_routing(struct kvm_kernel_irqfd * irqfd,struct kvm_kernel_irq_routing_entry * old,struct kvm_kernel_irq_routing_entry * new)2788 void kvm_arch_update_irqfd_routing(struct kvm_kernel_irqfd *irqfd,
2789 struct kvm_kernel_irq_routing_entry *old,
2790 struct kvm_kernel_irq_routing_entry *new)
2791 {
2792 if (old->type == KVM_IRQ_ROUTING_MSI &&
2793 new->type == KVM_IRQ_ROUTING_MSI &&
2794 !memcmp(&old->msi, &new->msi, sizeof(new->msi)))
2795 return;
2796
2797 /*
2798 * Remapping the vLPI requires taking the its_lock mutex to resolve
2799 * the new translation. We're in spinlock land at this point, so no
2800 * chance of resolving the translation.
2801 *
2802 * Unmap the vLPI and fall back to software LPI injection.
2803 */
2804 return kvm_vgic_v4_unset_forwarding(irqfd->kvm, irqfd->producer->irq);
2805 }
2806
kvm_arch_irq_bypass_stop(struct irq_bypass_consumer * cons)2807 void kvm_arch_irq_bypass_stop(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_halt_guest(irqfd->kvm);
2813 }
2814
kvm_arch_irq_bypass_start(struct irq_bypass_consumer * cons)2815 void kvm_arch_irq_bypass_start(struct irq_bypass_consumer *cons)
2816 {
2817 struct kvm_kernel_irqfd *irqfd =
2818 container_of(cons, struct kvm_kernel_irqfd, consumer);
2819
2820 kvm_arm_resume_guest(irqfd->kvm);
2821 }
2822
2823 /* Initialize Hyp-mode and memory mappings on all CPUs */
kvm_arm_init(void)2824 static __init int kvm_arm_init(void)
2825 {
2826 int err;
2827 bool in_hyp_mode;
2828
2829 if (!is_hyp_mode_available()) {
2830 kvm_info("HYP mode not available\n");
2831 return -ENODEV;
2832 }
2833
2834 if (kvm_get_mode() == KVM_MODE_NONE) {
2835 kvm_info("KVM disabled from command line\n");
2836 return -ENODEV;
2837 }
2838
2839 err = kvm_sys_reg_table_init();
2840 if (err) {
2841 kvm_info("Error initializing system register tables");
2842 return err;
2843 }
2844
2845 in_hyp_mode = is_kernel_in_hyp_mode();
2846
2847 if (cpus_have_final_cap(ARM64_WORKAROUND_DEVICE_LOAD_ACQUIRE) ||
2848 cpus_have_final_cap(ARM64_WORKAROUND_1508412))
2849 kvm_info("Guests without required CPU erratum workarounds can deadlock system!\n" \
2850 "Only trusted guests should be used on this system.\n");
2851
2852 err = kvm_set_ipa_limit();
2853 if (err)
2854 return err;
2855
2856 err = kvm_arm_init_sve();
2857 if (err)
2858 return err;
2859
2860 err = kvm_arm_vmid_alloc_init();
2861 if (err) {
2862 kvm_err("Failed to initialize VMID allocator.\n");
2863 return err;
2864 }
2865
2866 if (!in_hyp_mode) {
2867 err = init_hyp_mode();
2868 if (err)
2869 goto out_err;
2870 }
2871
2872 err = kvm_init_vector_slots();
2873 if (err) {
2874 kvm_err("Cannot initialise vector slots\n");
2875 goto out_hyp;
2876 }
2877
2878 err = init_subsystems();
2879 if (err)
2880 goto out_hyp;
2881
2882 kvm_info("%s%sVHE%s mode initialized successfully\n",
2883 in_hyp_mode ? "" : (is_protected_kvm_enabled() ?
2884 "Protected " : "Hyp "),
2885 in_hyp_mode ? "" : (cpus_have_final_cap(ARM64_KVM_HVHE) ?
2886 "h" : "n"),
2887 cpus_have_final_cap(ARM64_HAS_NESTED_VIRT) ? "+NV2": "");
2888
2889 /*
2890 * FIXME: Do something reasonable if kvm_init() fails after pKVM
2891 * hypervisor protection is finalized.
2892 */
2893 err = kvm_init(sizeof(struct kvm_vcpu), 0, THIS_MODULE);
2894 if (err)
2895 goto out_subs;
2896
2897 /*
2898 * This should be called after initialization is done and failure isn't
2899 * possible anymore.
2900 */
2901 if (!in_hyp_mode)
2902 finalize_init_hyp_mode();
2903
2904 kvm_arm_initialised = true;
2905
2906 return 0;
2907
2908 out_subs:
2909 teardown_subsystems();
2910 out_hyp:
2911 if (!in_hyp_mode)
2912 teardown_hyp_mode();
2913 out_err:
2914 kvm_arm_vmid_alloc_free();
2915 return err;
2916 }
2917
early_kvm_mode_cfg(char * arg)2918 static int __init early_kvm_mode_cfg(char *arg)
2919 {
2920 if (!arg)
2921 return -EINVAL;
2922
2923 if (strcmp(arg, "none") == 0) {
2924 kvm_mode = KVM_MODE_NONE;
2925 return 0;
2926 }
2927
2928 if (!is_hyp_mode_available()) {
2929 pr_warn_once("KVM is not available. Ignoring kvm-arm.mode\n");
2930 return 0;
2931 }
2932
2933 if (strcmp(arg, "protected") == 0) {
2934 if (!is_kernel_in_hyp_mode())
2935 kvm_mode = KVM_MODE_PROTECTED;
2936 else
2937 pr_warn_once("Protected KVM not available with VHE\n");
2938
2939 return 0;
2940 }
2941
2942 if (strcmp(arg, "nvhe") == 0 && !WARN_ON(is_kernel_in_hyp_mode())) {
2943 kvm_mode = KVM_MODE_DEFAULT;
2944 return 0;
2945 }
2946
2947 if (strcmp(arg, "nested") == 0 && !WARN_ON(!is_kernel_in_hyp_mode())) {
2948 kvm_mode = KVM_MODE_NV;
2949 return 0;
2950 }
2951
2952 return -EINVAL;
2953 }
2954 early_param("kvm-arm.mode", early_kvm_mode_cfg);
2955
early_kvm_wfx_trap_policy_cfg(char * arg,enum kvm_wfx_trap_policy * p)2956 static int __init early_kvm_wfx_trap_policy_cfg(char *arg, enum kvm_wfx_trap_policy *p)
2957 {
2958 if (!arg)
2959 return -EINVAL;
2960
2961 if (strcmp(arg, "trap") == 0) {
2962 *p = KVM_WFX_TRAP;
2963 return 0;
2964 }
2965
2966 if (strcmp(arg, "notrap") == 0) {
2967 *p = KVM_WFX_NOTRAP;
2968 return 0;
2969 }
2970
2971 return -EINVAL;
2972 }
2973
early_kvm_wfi_trap_policy_cfg(char * arg)2974 static int __init early_kvm_wfi_trap_policy_cfg(char *arg)
2975 {
2976 return early_kvm_wfx_trap_policy_cfg(arg, &kvm_wfi_trap_policy);
2977 }
2978 early_param("kvm-arm.wfi_trap_policy", early_kvm_wfi_trap_policy_cfg);
2979
early_kvm_wfe_trap_policy_cfg(char * arg)2980 static int __init early_kvm_wfe_trap_policy_cfg(char *arg)
2981 {
2982 return early_kvm_wfx_trap_policy_cfg(arg, &kvm_wfe_trap_policy);
2983 }
2984 early_param("kvm-arm.wfe_trap_policy", early_kvm_wfe_trap_policy_cfg);
2985
kvm_get_mode(void)2986 enum kvm_mode kvm_get_mode(void)
2987 {
2988 return kvm_mode;
2989 }
2990
2991 module_init(kvm_arm_init);
2992