1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Kernel-based Virtual Machine driver for Linux 4 * 5 * AMD SVM support 6 * 7 * Copyright (C) 2006 Qumranet, Inc. 8 * Copyright 2010 Red Hat, Inc. and/or its affiliates. 9 * 10 * Authors: 11 * Yaniv Kamay <yaniv@qumranet.com> 12 * Avi Kivity <avi@qumranet.com> 13 */ 14 15 #define pr_fmt(fmt) "SVM: " fmt 16 17 #include <linux/kvm_types.h> 18 #include <linux/kvm_host.h> 19 #include <linux/kernel.h> 20 21 #include <asm/msr-index.h> 22 #include <asm/debugreg.h> 23 24 #include "kvm_emulate.h" 25 #include "trace.h" 26 #include "mmu.h" 27 #include "x86.h" 28 #include "cpuid.h" 29 #include "lapic.h" 30 #include "svm.h" 31 32 static void nested_svm_inject_npf_exit(struct kvm_vcpu *vcpu, 33 struct x86_exception *fault) 34 { 35 struct vcpu_svm *svm = to_svm(vcpu); 36 37 if (svm->vmcb->control.exit_code != SVM_EXIT_NPF) { 38 /* 39 * TODO: track the cause of the nested page fault, and 40 * correctly fill in the high bits of exit_info_1. 41 */ 42 svm->vmcb->control.exit_code = SVM_EXIT_NPF; 43 svm->vmcb->control.exit_code_hi = 0; 44 svm->vmcb->control.exit_info_1 = (1ULL << 32); 45 svm->vmcb->control.exit_info_2 = fault->address; 46 } 47 48 svm->vmcb->control.exit_info_1 &= ~0xffffffffULL; 49 svm->vmcb->control.exit_info_1 |= fault->error_code; 50 51 /* 52 * The present bit is always zero for page structure faults on real 53 * hardware. 54 */ 55 if (svm->vmcb->control.exit_info_1 & (2ULL << 32)) 56 svm->vmcb->control.exit_info_1 &= ~1; 57 58 nested_svm_vmexit(svm); 59 } 60 61 static u64 nested_svm_get_tdp_pdptr(struct kvm_vcpu *vcpu, int index) 62 { 63 struct vcpu_svm *svm = to_svm(vcpu); 64 u64 cr3 = svm->nested.ctl.nested_cr3; 65 u64 pdpte; 66 int ret; 67 68 ret = kvm_vcpu_read_guest_page(vcpu, gpa_to_gfn(__sme_clr(cr3)), &pdpte, 69 offset_in_page(cr3) + index * 8, 8); 70 if (ret) 71 return 0; 72 return pdpte; 73 } 74 75 static unsigned long nested_svm_get_tdp_cr3(struct kvm_vcpu *vcpu) 76 { 77 struct vcpu_svm *svm = to_svm(vcpu); 78 79 return svm->nested.ctl.nested_cr3; 80 } 81 82 static void nested_svm_init_mmu_context(struct kvm_vcpu *vcpu) 83 { 84 struct vcpu_svm *svm = to_svm(vcpu); 85 struct vmcb *hsave = svm->nested.hsave; 86 87 WARN_ON(mmu_is_nested(vcpu)); 88 89 vcpu->arch.mmu = &vcpu->arch.guest_mmu; 90 kvm_init_shadow_mmu(vcpu, X86_CR0_PG, hsave->save.cr4, hsave->save.efer); 91 vcpu->arch.mmu->get_guest_pgd = nested_svm_get_tdp_cr3; 92 vcpu->arch.mmu->get_pdptr = nested_svm_get_tdp_pdptr; 93 vcpu->arch.mmu->inject_page_fault = nested_svm_inject_npf_exit; 94 vcpu->arch.mmu->shadow_root_level = vcpu->arch.tdp_level; 95 reset_shadow_zero_bits_mask(vcpu, vcpu->arch.mmu); 96 vcpu->arch.walk_mmu = &vcpu->arch.nested_mmu; 97 } 98 99 static void nested_svm_uninit_mmu_context(struct kvm_vcpu *vcpu) 100 { 101 vcpu->arch.mmu = &vcpu->arch.root_mmu; 102 vcpu->arch.walk_mmu = &vcpu->arch.root_mmu; 103 } 104 105 void recalc_intercepts(struct vcpu_svm *svm) 106 { 107 struct vmcb_control_area *c, *h, *g; 108 109 mark_dirty(svm->vmcb, VMCB_INTERCEPTS); 110 111 if (!is_guest_mode(&svm->vcpu)) 112 return; 113 114 c = &svm->vmcb->control; 115 h = &svm->nested.hsave->control; 116 g = &svm->nested.ctl; 117 118 svm->nested.host_intercept_exceptions = h->intercept_exceptions; 119 120 c->intercept_cr = h->intercept_cr; 121 c->intercept_dr = h->intercept_dr; 122 c->intercept_exceptions = h->intercept_exceptions; 123 c->intercept = h->intercept; 124 125 if (g->int_ctl & V_INTR_MASKING_MASK) { 126 /* We only want the cr8 intercept bits of L1 */ 127 c->intercept_cr &= ~(1U << INTERCEPT_CR8_READ); 128 c->intercept_cr &= ~(1U << INTERCEPT_CR8_WRITE); 129 130 /* 131 * Once running L2 with HF_VINTR_MASK, EFLAGS.IF does not 132 * affect any interrupt we may want to inject; therefore, 133 * interrupt window vmexits are irrelevant to L0. 134 */ 135 c->intercept &= ~(1ULL << INTERCEPT_VINTR); 136 } 137 138 /* We don't want to see VMMCALLs from a nested guest */ 139 c->intercept &= ~(1ULL << INTERCEPT_VMMCALL); 140 141 c->intercept_cr |= g->intercept_cr; 142 c->intercept_dr |= g->intercept_dr; 143 c->intercept_exceptions |= g->intercept_exceptions; 144 c->intercept |= g->intercept; 145 } 146 147 static void copy_vmcb_control_area(struct vmcb_control_area *dst, 148 struct vmcb_control_area *from) 149 { 150 dst->intercept_cr = from->intercept_cr; 151 dst->intercept_dr = from->intercept_dr; 152 dst->intercept_exceptions = from->intercept_exceptions; 153 dst->intercept = from->intercept; 154 dst->iopm_base_pa = from->iopm_base_pa; 155 dst->msrpm_base_pa = from->msrpm_base_pa; 156 dst->tsc_offset = from->tsc_offset; 157 /* asid not copied, it is handled manually for svm->vmcb. */ 158 dst->tlb_ctl = from->tlb_ctl; 159 dst->int_ctl = from->int_ctl; 160 dst->int_vector = from->int_vector; 161 dst->int_state = from->int_state; 162 dst->exit_code = from->exit_code; 163 dst->exit_code_hi = from->exit_code_hi; 164 dst->exit_info_1 = from->exit_info_1; 165 dst->exit_info_2 = from->exit_info_2; 166 dst->exit_int_info = from->exit_int_info; 167 dst->exit_int_info_err = from->exit_int_info_err; 168 dst->nested_ctl = from->nested_ctl; 169 dst->event_inj = from->event_inj; 170 dst->event_inj_err = from->event_inj_err; 171 dst->nested_cr3 = from->nested_cr3; 172 dst->virt_ext = from->virt_ext; 173 dst->pause_filter_count = from->pause_filter_count; 174 dst->pause_filter_thresh = from->pause_filter_thresh; 175 } 176 177 static bool nested_svm_vmrun_msrpm(struct vcpu_svm *svm) 178 { 179 /* 180 * This function merges the msr permission bitmaps of kvm and the 181 * nested vmcb. It is optimized in that it only merges the parts where 182 * the kvm msr permission bitmap may contain zero bits 183 */ 184 int i; 185 186 if (!(svm->nested.ctl.intercept & (1ULL << INTERCEPT_MSR_PROT))) 187 return true; 188 189 for (i = 0; i < MSRPM_OFFSETS; i++) { 190 u32 value, p; 191 u64 offset; 192 193 if (msrpm_offsets[i] == 0xffffffff) 194 break; 195 196 p = msrpm_offsets[i]; 197 offset = svm->nested.ctl.msrpm_base_pa + (p * 4); 198 199 if (kvm_vcpu_read_guest(&svm->vcpu, offset, &value, 4)) 200 return false; 201 202 svm->nested.msrpm[p] = svm->msrpm[p] | value; 203 } 204 205 svm->vmcb->control.msrpm_base_pa = __sme_set(__pa(svm->nested.msrpm)); 206 207 return true; 208 } 209 210 static bool nested_vmcb_check_controls(struct vmcb_control_area *control) 211 { 212 if ((control->intercept & (1ULL << INTERCEPT_VMRUN)) == 0) 213 return false; 214 215 if (control->asid == 0) 216 return false; 217 218 if ((control->nested_ctl & SVM_NESTED_CTL_NP_ENABLE) && 219 !npt_enabled) 220 return false; 221 222 return true; 223 } 224 225 static bool nested_vmcb_checks(struct vmcb *vmcb) 226 { 227 if ((vmcb->save.efer & EFER_SVME) == 0) 228 return false; 229 230 if (((vmcb->save.cr0 & X86_CR0_CD) == 0) && 231 (vmcb->save.cr0 & X86_CR0_NW)) 232 return false; 233 234 return nested_vmcb_check_controls(&vmcb->control); 235 } 236 237 static void load_nested_vmcb_control(struct vcpu_svm *svm, 238 struct vmcb_control_area *control) 239 { 240 copy_vmcb_control_area(&svm->nested.ctl, control); 241 242 /* Copy it here because nested_svm_check_controls will check it. */ 243 svm->nested.ctl.asid = control->asid; 244 svm->nested.ctl.msrpm_base_pa &= ~0x0fffULL; 245 svm->nested.ctl.iopm_base_pa &= ~0x0fffULL; 246 } 247 248 /* 249 * Synchronize fields that are written by the processor, so that 250 * they can be copied back into the nested_vmcb. 251 */ 252 void sync_nested_vmcb_control(struct vcpu_svm *svm) 253 { 254 u32 mask; 255 svm->nested.ctl.event_inj = svm->vmcb->control.event_inj; 256 svm->nested.ctl.event_inj_err = svm->vmcb->control.event_inj_err; 257 258 /* Only a few fields of int_ctl are written by the processor. */ 259 mask = V_IRQ_MASK | V_TPR_MASK; 260 if (!(svm->nested.ctl.int_ctl & V_INTR_MASKING_MASK) && 261 is_intercept(svm, SVM_EXIT_VINTR)) { 262 /* 263 * In order to request an interrupt window, L0 is usurping 264 * svm->vmcb->control.int_ctl and possibly setting V_IRQ 265 * even if it was clear in L1's VMCB. Restoring it would be 266 * wrong. However, in this case V_IRQ will remain true until 267 * interrupt_window_interception calls svm_clear_vintr and 268 * restores int_ctl. We can just leave it aside. 269 */ 270 mask &= ~V_IRQ_MASK; 271 } 272 svm->nested.ctl.int_ctl &= ~mask; 273 svm->nested.ctl.int_ctl |= svm->vmcb->control.int_ctl & mask; 274 } 275 276 /* 277 * Transfer any event that L0 or L1 wanted to inject into L2 to 278 * EXIT_INT_INFO. 279 */ 280 static void nested_vmcb_save_pending_event(struct vcpu_svm *svm, 281 struct vmcb *nested_vmcb) 282 { 283 struct kvm_vcpu *vcpu = &svm->vcpu; 284 u32 exit_int_info = 0; 285 unsigned int nr; 286 287 if (vcpu->arch.exception.injected) { 288 nr = vcpu->arch.exception.nr; 289 exit_int_info = nr | SVM_EVTINJ_VALID | SVM_EVTINJ_TYPE_EXEPT; 290 291 if (vcpu->arch.exception.has_error_code) { 292 exit_int_info |= SVM_EVTINJ_VALID_ERR; 293 nested_vmcb->control.exit_int_info_err = 294 vcpu->arch.exception.error_code; 295 } 296 297 } else if (vcpu->arch.nmi_injected) { 298 exit_int_info = SVM_EVTINJ_VALID | SVM_EVTINJ_TYPE_NMI; 299 300 } else if (vcpu->arch.interrupt.injected) { 301 nr = vcpu->arch.interrupt.nr; 302 exit_int_info = nr | SVM_EVTINJ_VALID; 303 304 if (vcpu->arch.interrupt.soft) 305 exit_int_info |= SVM_EVTINJ_TYPE_SOFT; 306 else 307 exit_int_info |= SVM_EVTINJ_TYPE_INTR; 308 } 309 310 nested_vmcb->control.exit_int_info = exit_int_info; 311 } 312 313 static void nested_prepare_vmcb_save(struct vcpu_svm *svm, struct vmcb *nested_vmcb) 314 { 315 /* Load the nested guest state */ 316 svm->vmcb->save.es = nested_vmcb->save.es; 317 svm->vmcb->save.cs = nested_vmcb->save.cs; 318 svm->vmcb->save.ss = nested_vmcb->save.ss; 319 svm->vmcb->save.ds = nested_vmcb->save.ds; 320 svm->vmcb->save.gdtr = nested_vmcb->save.gdtr; 321 svm->vmcb->save.idtr = nested_vmcb->save.idtr; 322 kvm_set_rflags(&svm->vcpu, nested_vmcb->save.rflags); 323 svm_set_efer(&svm->vcpu, nested_vmcb->save.efer); 324 svm_set_cr0(&svm->vcpu, nested_vmcb->save.cr0); 325 svm_set_cr4(&svm->vcpu, nested_vmcb->save.cr4); 326 (void)kvm_set_cr3(&svm->vcpu, nested_vmcb->save.cr3); 327 328 svm->vmcb->save.cr2 = svm->vcpu.arch.cr2 = nested_vmcb->save.cr2; 329 kvm_rax_write(&svm->vcpu, nested_vmcb->save.rax); 330 kvm_rsp_write(&svm->vcpu, nested_vmcb->save.rsp); 331 kvm_rip_write(&svm->vcpu, nested_vmcb->save.rip); 332 333 /* In case we don't even reach vcpu_run, the fields are not updated */ 334 svm->vmcb->save.rax = nested_vmcb->save.rax; 335 svm->vmcb->save.rsp = nested_vmcb->save.rsp; 336 svm->vmcb->save.rip = nested_vmcb->save.rip; 337 svm->vmcb->save.dr7 = nested_vmcb->save.dr7; 338 svm->vcpu.arch.dr6 = nested_vmcb->save.dr6; 339 svm->vmcb->save.cpl = nested_vmcb->save.cpl; 340 } 341 342 static void nested_prepare_vmcb_control(struct vcpu_svm *svm) 343 { 344 const u32 mask = V_INTR_MASKING_MASK | V_GIF_ENABLE_MASK | V_GIF_MASK; 345 if (svm->nested.ctl.nested_ctl & SVM_NESTED_CTL_NP_ENABLE) 346 nested_svm_init_mmu_context(&svm->vcpu); 347 348 /* Guest paging mode is active - reset mmu */ 349 kvm_mmu_reset_context(&svm->vcpu); 350 351 svm_flush_tlb(&svm->vcpu); 352 353 svm->vmcb->control.tsc_offset = svm->vcpu.arch.tsc_offset = 354 svm->vcpu.arch.l1_tsc_offset + svm->nested.ctl.tsc_offset; 355 356 svm->vmcb->control.int_ctl = 357 (svm->nested.ctl.int_ctl & ~mask) | 358 (svm->nested.hsave->control.int_ctl & mask); 359 360 svm->vmcb->control.virt_ext = svm->nested.ctl.virt_ext; 361 svm->vmcb->control.int_vector = svm->nested.ctl.int_vector; 362 svm->vmcb->control.int_state = svm->nested.ctl.int_state; 363 svm->vmcb->control.event_inj = svm->nested.ctl.event_inj; 364 svm->vmcb->control.event_inj_err = svm->nested.ctl.event_inj_err; 365 366 svm->vmcb->control.pause_filter_count = svm->nested.ctl.pause_filter_count; 367 svm->vmcb->control.pause_filter_thresh = svm->nested.ctl.pause_filter_thresh; 368 369 /* Enter Guest-Mode */ 370 enter_guest_mode(&svm->vcpu); 371 372 /* 373 * Merge guest and host intercepts - must be called with vcpu in 374 * guest-mode to take affect here 375 */ 376 recalc_intercepts(svm); 377 378 mark_all_dirty(svm->vmcb); 379 } 380 381 void enter_svm_guest_mode(struct vcpu_svm *svm, u64 vmcb_gpa, 382 struct vmcb *nested_vmcb) 383 { 384 svm->nested.vmcb = vmcb_gpa; 385 load_nested_vmcb_control(svm, &nested_vmcb->control); 386 nested_prepare_vmcb_save(svm, nested_vmcb); 387 nested_prepare_vmcb_control(svm); 388 389 svm_set_gif(svm, true); 390 } 391 392 int nested_svm_vmrun(struct vcpu_svm *svm) 393 { 394 int ret; 395 struct vmcb *nested_vmcb; 396 struct vmcb *hsave = svm->nested.hsave; 397 struct vmcb *vmcb = svm->vmcb; 398 struct kvm_host_map map; 399 u64 vmcb_gpa; 400 401 if (is_smm(&svm->vcpu)) { 402 kvm_queue_exception(&svm->vcpu, UD_VECTOR); 403 return 1; 404 } 405 406 vmcb_gpa = svm->vmcb->save.rax; 407 ret = kvm_vcpu_map(&svm->vcpu, gpa_to_gfn(vmcb_gpa), &map); 408 if (ret == -EINVAL) { 409 kvm_inject_gp(&svm->vcpu, 0); 410 return 1; 411 } else if (ret) { 412 return kvm_skip_emulated_instruction(&svm->vcpu); 413 } 414 415 ret = kvm_skip_emulated_instruction(&svm->vcpu); 416 417 nested_vmcb = map.hva; 418 419 if (!nested_vmcb_checks(nested_vmcb)) { 420 nested_vmcb->control.exit_code = SVM_EXIT_ERR; 421 nested_vmcb->control.exit_code_hi = 0; 422 nested_vmcb->control.exit_info_1 = 0; 423 nested_vmcb->control.exit_info_2 = 0; 424 goto out; 425 } 426 427 trace_kvm_nested_vmrun(svm->vmcb->save.rip, vmcb_gpa, 428 nested_vmcb->save.rip, 429 nested_vmcb->control.int_ctl, 430 nested_vmcb->control.event_inj, 431 nested_vmcb->control.nested_ctl); 432 433 trace_kvm_nested_intercepts(nested_vmcb->control.intercept_cr & 0xffff, 434 nested_vmcb->control.intercept_cr >> 16, 435 nested_vmcb->control.intercept_exceptions, 436 nested_vmcb->control.intercept); 437 438 /* Clear internal status */ 439 kvm_clear_exception_queue(&svm->vcpu); 440 kvm_clear_interrupt_queue(&svm->vcpu); 441 442 /* 443 * Save the old vmcb, so we don't need to pick what we save, but can 444 * restore everything when a VMEXIT occurs 445 */ 446 hsave->save.es = vmcb->save.es; 447 hsave->save.cs = vmcb->save.cs; 448 hsave->save.ss = vmcb->save.ss; 449 hsave->save.ds = vmcb->save.ds; 450 hsave->save.gdtr = vmcb->save.gdtr; 451 hsave->save.idtr = vmcb->save.idtr; 452 hsave->save.efer = svm->vcpu.arch.efer; 453 hsave->save.cr0 = kvm_read_cr0(&svm->vcpu); 454 hsave->save.cr4 = svm->vcpu.arch.cr4; 455 hsave->save.rflags = kvm_get_rflags(&svm->vcpu); 456 hsave->save.rip = kvm_rip_read(&svm->vcpu); 457 hsave->save.rsp = vmcb->save.rsp; 458 hsave->save.rax = vmcb->save.rax; 459 if (npt_enabled) 460 hsave->save.cr3 = vmcb->save.cr3; 461 else 462 hsave->save.cr3 = kvm_read_cr3(&svm->vcpu); 463 464 copy_vmcb_control_area(&hsave->control, &vmcb->control); 465 466 svm->nested.nested_run_pending = 1; 467 enter_svm_guest_mode(svm, vmcb_gpa, nested_vmcb); 468 469 if (!nested_svm_vmrun_msrpm(svm)) { 470 svm->vmcb->control.exit_code = SVM_EXIT_ERR; 471 svm->vmcb->control.exit_code_hi = 0; 472 svm->vmcb->control.exit_info_1 = 0; 473 svm->vmcb->control.exit_info_2 = 0; 474 475 nested_svm_vmexit(svm); 476 } 477 478 out: 479 kvm_vcpu_unmap(&svm->vcpu, &map, true); 480 481 return ret; 482 } 483 484 void nested_svm_vmloadsave(struct vmcb *from_vmcb, struct vmcb *to_vmcb) 485 { 486 to_vmcb->save.fs = from_vmcb->save.fs; 487 to_vmcb->save.gs = from_vmcb->save.gs; 488 to_vmcb->save.tr = from_vmcb->save.tr; 489 to_vmcb->save.ldtr = from_vmcb->save.ldtr; 490 to_vmcb->save.kernel_gs_base = from_vmcb->save.kernel_gs_base; 491 to_vmcb->save.star = from_vmcb->save.star; 492 to_vmcb->save.lstar = from_vmcb->save.lstar; 493 to_vmcb->save.cstar = from_vmcb->save.cstar; 494 to_vmcb->save.sfmask = from_vmcb->save.sfmask; 495 to_vmcb->save.sysenter_cs = from_vmcb->save.sysenter_cs; 496 to_vmcb->save.sysenter_esp = from_vmcb->save.sysenter_esp; 497 to_vmcb->save.sysenter_eip = from_vmcb->save.sysenter_eip; 498 } 499 500 int nested_svm_vmexit(struct vcpu_svm *svm) 501 { 502 int rc; 503 struct vmcb *nested_vmcb; 504 struct vmcb *hsave = svm->nested.hsave; 505 struct vmcb *vmcb = svm->vmcb; 506 struct kvm_host_map map; 507 508 rc = kvm_vcpu_map(&svm->vcpu, gpa_to_gfn(svm->nested.vmcb), &map); 509 if (rc) { 510 if (rc == -EINVAL) 511 kvm_inject_gp(&svm->vcpu, 0); 512 return 1; 513 } 514 515 nested_vmcb = map.hva; 516 517 /* Exit Guest-Mode */ 518 leave_guest_mode(&svm->vcpu); 519 svm->nested.vmcb = 0; 520 WARN_ON_ONCE(svm->nested.nested_run_pending); 521 522 /* in case we halted in L2 */ 523 svm->vcpu.arch.mp_state = KVM_MP_STATE_RUNNABLE; 524 525 /* Give the current vmcb to the guest */ 526 svm_set_gif(svm, false); 527 528 nested_vmcb->save.es = vmcb->save.es; 529 nested_vmcb->save.cs = vmcb->save.cs; 530 nested_vmcb->save.ss = vmcb->save.ss; 531 nested_vmcb->save.ds = vmcb->save.ds; 532 nested_vmcb->save.gdtr = vmcb->save.gdtr; 533 nested_vmcb->save.idtr = vmcb->save.idtr; 534 nested_vmcb->save.efer = svm->vcpu.arch.efer; 535 nested_vmcb->save.cr0 = kvm_read_cr0(&svm->vcpu); 536 nested_vmcb->save.cr3 = kvm_read_cr3(&svm->vcpu); 537 nested_vmcb->save.cr2 = vmcb->save.cr2; 538 nested_vmcb->save.cr4 = svm->vcpu.arch.cr4; 539 nested_vmcb->save.rflags = kvm_get_rflags(&svm->vcpu); 540 nested_vmcb->save.rip = kvm_rip_read(&svm->vcpu); 541 nested_vmcb->save.rsp = kvm_rsp_read(&svm->vcpu); 542 nested_vmcb->save.rax = kvm_rax_read(&svm->vcpu); 543 nested_vmcb->save.dr7 = vmcb->save.dr7; 544 nested_vmcb->save.dr6 = svm->vcpu.arch.dr6; 545 nested_vmcb->save.cpl = vmcb->save.cpl; 546 547 nested_vmcb->control.int_state = vmcb->control.int_state; 548 nested_vmcb->control.exit_code = vmcb->control.exit_code; 549 nested_vmcb->control.exit_code_hi = vmcb->control.exit_code_hi; 550 nested_vmcb->control.exit_info_1 = vmcb->control.exit_info_1; 551 nested_vmcb->control.exit_info_2 = vmcb->control.exit_info_2; 552 553 if (nested_vmcb->control.exit_code != SVM_EXIT_ERR) 554 nested_vmcb_save_pending_event(svm, nested_vmcb); 555 556 if (svm->nrips_enabled) 557 nested_vmcb->control.next_rip = vmcb->control.next_rip; 558 559 nested_vmcb->control.int_ctl = svm->nested.ctl.int_ctl; 560 nested_vmcb->control.tlb_ctl = svm->nested.ctl.tlb_ctl; 561 nested_vmcb->control.event_inj = svm->nested.ctl.event_inj; 562 nested_vmcb->control.event_inj_err = svm->nested.ctl.event_inj_err; 563 564 nested_vmcb->control.pause_filter_count = 565 svm->vmcb->control.pause_filter_count; 566 nested_vmcb->control.pause_filter_thresh = 567 svm->vmcb->control.pause_filter_thresh; 568 569 /* Restore the original control entries */ 570 copy_vmcb_control_area(&vmcb->control, &hsave->control); 571 572 svm->vmcb->control.tsc_offset = svm->vcpu.arch.tsc_offset = 573 svm->vcpu.arch.l1_tsc_offset; 574 575 svm->nested.ctl.nested_cr3 = 0; 576 577 /* Restore selected save entries */ 578 svm->vmcb->save.es = hsave->save.es; 579 svm->vmcb->save.cs = hsave->save.cs; 580 svm->vmcb->save.ss = hsave->save.ss; 581 svm->vmcb->save.ds = hsave->save.ds; 582 svm->vmcb->save.gdtr = hsave->save.gdtr; 583 svm->vmcb->save.idtr = hsave->save.idtr; 584 kvm_set_rflags(&svm->vcpu, hsave->save.rflags); 585 svm_set_efer(&svm->vcpu, hsave->save.efer); 586 svm_set_cr0(&svm->vcpu, hsave->save.cr0 | X86_CR0_PE); 587 svm_set_cr4(&svm->vcpu, hsave->save.cr4); 588 if (npt_enabled) { 589 svm->vmcb->save.cr3 = hsave->save.cr3; 590 svm->vcpu.arch.cr3 = hsave->save.cr3; 591 } else { 592 (void)kvm_set_cr3(&svm->vcpu, hsave->save.cr3); 593 } 594 kvm_rax_write(&svm->vcpu, hsave->save.rax); 595 kvm_rsp_write(&svm->vcpu, hsave->save.rsp); 596 kvm_rip_write(&svm->vcpu, hsave->save.rip); 597 svm->vmcb->save.dr7 = 0; 598 svm->vmcb->save.cpl = 0; 599 svm->vmcb->control.exit_int_info = 0; 600 601 mark_all_dirty(svm->vmcb); 602 603 trace_kvm_nested_vmexit_inject(nested_vmcb->control.exit_code, 604 nested_vmcb->control.exit_info_1, 605 nested_vmcb->control.exit_info_2, 606 nested_vmcb->control.exit_int_info, 607 nested_vmcb->control.exit_int_info_err, 608 KVM_ISA_SVM); 609 610 kvm_vcpu_unmap(&svm->vcpu, &map, true); 611 612 nested_svm_uninit_mmu_context(&svm->vcpu); 613 kvm_mmu_reset_context(&svm->vcpu); 614 kvm_mmu_load(&svm->vcpu); 615 616 /* 617 * Drop what we picked up for L2 via svm_complete_interrupts() so it 618 * doesn't end up in L1. 619 */ 620 svm->vcpu.arch.nmi_injected = false; 621 kvm_clear_exception_queue(&svm->vcpu); 622 kvm_clear_interrupt_queue(&svm->vcpu); 623 624 return 0; 625 } 626 627 /* 628 * Forcibly leave nested mode in order to be able to reset the VCPU later on. 629 */ 630 void svm_leave_nested(struct vcpu_svm *svm) 631 { 632 if (is_guest_mode(&svm->vcpu)) { 633 struct vmcb *hsave = svm->nested.hsave; 634 struct vmcb *vmcb = svm->vmcb; 635 636 svm->nested.nested_run_pending = 0; 637 leave_guest_mode(&svm->vcpu); 638 copy_vmcb_control_area(&vmcb->control, &hsave->control); 639 nested_svm_uninit_mmu_context(&svm->vcpu); 640 } 641 } 642 643 static int nested_svm_exit_handled_msr(struct vcpu_svm *svm) 644 { 645 u32 offset, msr, value; 646 int write, mask; 647 648 if (!(svm->nested.ctl.intercept & (1ULL << INTERCEPT_MSR_PROT))) 649 return NESTED_EXIT_HOST; 650 651 msr = svm->vcpu.arch.regs[VCPU_REGS_RCX]; 652 offset = svm_msrpm_offset(msr); 653 write = svm->vmcb->control.exit_info_1 & 1; 654 mask = 1 << ((2 * (msr & 0xf)) + write); 655 656 if (offset == MSR_INVALID) 657 return NESTED_EXIT_DONE; 658 659 /* Offset is in 32 bit units but need in 8 bit units */ 660 offset *= 4; 661 662 if (kvm_vcpu_read_guest(&svm->vcpu, svm->nested.ctl.msrpm_base_pa + offset, &value, 4)) 663 return NESTED_EXIT_DONE; 664 665 return (value & mask) ? NESTED_EXIT_DONE : NESTED_EXIT_HOST; 666 } 667 668 static int nested_svm_intercept_ioio(struct vcpu_svm *svm) 669 { 670 unsigned port, size, iopm_len; 671 u16 val, mask; 672 u8 start_bit; 673 u64 gpa; 674 675 if (!(svm->nested.ctl.intercept & (1ULL << INTERCEPT_IOIO_PROT))) 676 return NESTED_EXIT_HOST; 677 678 port = svm->vmcb->control.exit_info_1 >> 16; 679 size = (svm->vmcb->control.exit_info_1 & SVM_IOIO_SIZE_MASK) >> 680 SVM_IOIO_SIZE_SHIFT; 681 gpa = svm->nested.ctl.iopm_base_pa + (port / 8); 682 start_bit = port % 8; 683 iopm_len = (start_bit + size > 8) ? 2 : 1; 684 mask = (0xf >> (4 - size)) << start_bit; 685 val = 0; 686 687 if (kvm_vcpu_read_guest(&svm->vcpu, gpa, &val, iopm_len)) 688 return NESTED_EXIT_DONE; 689 690 return (val & mask) ? NESTED_EXIT_DONE : NESTED_EXIT_HOST; 691 } 692 693 static int nested_svm_intercept(struct vcpu_svm *svm) 694 { 695 u32 exit_code = svm->vmcb->control.exit_code; 696 int vmexit = NESTED_EXIT_HOST; 697 698 switch (exit_code) { 699 case SVM_EXIT_MSR: 700 vmexit = nested_svm_exit_handled_msr(svm); 701 break; 702 case SVM_EXIT_IOIO: 703 vmexit = nested_svm_intercept_ioio(svm); 704 break; 705 case SVM_EXIT_READ_CR0 ... SVM_EXIT_WRITE_CR8: { 706 u32 bit = 1U << (exit_code - SVM_EXIT_READ_CR0); 707 if (svm->nested.ctl.intercept_cr & bit) 708 vmexit = NESTED_EXIT_DONE; 709 break; 710 } 711 case SVM_EXIT_READ_DR0 ... SVM_EXIT_WRITE_DR7: { 712 u32 bit = 1U << (exit_code - SVM_EXIT_READ_DR0); 713 if (svm->nested.ctl.intercept_dr & bit) 714 vmexit = NESTED_EXIT_DONE; 715 break; 716 } 717 case SVM_EXIT_EXCP_BASE ... SVM_EXIT_EXCP_BASE + 0x1f: { 718 /* 719 * Host-intercepted exceptions have been checked already in 720 * nested_svm_exit_special. There is nothing to do here, 721 * the vmexit is injected by svm_check_nested_events. 722 */ 723 vmexit = NESTED_EXIT_DONE; 724 break; 725 } 726 case SVM_EXIT_ERR: { 727 vmexit = NESTED_EXIT_DONE; 728 break; 729 } 730 default: { 731 u64 exit_bits = 1ULL << (exit_code - SVM_EXIT_INTR); 732 if (svm->nested.ctl.intercept & exit_bits) 733 vmexit = NESTED_EXIT_DONE; 734 } 735 } 736 737 return vmexit; 738 } 739 740 int nested_svm_exit_handled(struct vcpu_svm *svm) 741 { 742 int vmexit; 743 744 vmexit = nested_svm_intercept(svm); 745 746 if (vmexit == NESTED_EXIT_DONE) 747 nested_svm_vmexit(svm); 748 749 return vmexit; 750 } 751 752 int nested_svm_check_permissions(struct vcpu_svm *svm) 753 { 754 if (!(svm->vcpu.arch.efer & EFER_SVME) || 755 !is_paging(&svm->vcpu)) { 756 kvm_queue_exception(&svm->vcpu, UD_VECTOR); 757 return 1; 758 } 759 760 if (svm->vmcb->save.cpl) { 761 kvm_inject_gp(&svm->vcpu, 0); 762 return 1; 763 } 764 765 return 0; 766 } 767 768 static bool nested_exit_on_exception(struct vcpu_svm *svm) 769 { 770 unsigned int nr = svm->vcpu.arch.exception.nr; 771 772 return (svm->nested.ctl.intercept_exceptions & (1 << nr)); 773 } 774 775 static void nested_svm_inject_exception_vmexit(struct vcpu_svm *svm) 776 { 777 unsigned int nr = svm->vcpu.arch.exception.nr; 778 779 svm->vmcb->control.exit_code = SVM_EXIT_EXCP_BASE + nr; 780 svm->vmcb->control.exit_code_hi = 0; 781 782 if (svm->vcpu.arch.exception.has_error_code) 783 svm->vmcb->control.exit_info_1 = svm->vcpu.arch.exception.error_code; 784 785 /* 786 * EXITINFO2 is undefined for all exception intercepts other 787 * than #PF. 788 */ 789 if (nr == PF_VECTOR) { 790 if (svm->vcpu.arch.exception.nested_apf) 791 svm->vmcb->control.exit_info_2 = svm->vcpu.arch.apf.nested_apf_token; 792 else if (svm->vcpu.arch.exception.has_payload) 793 svm->vmcb->control.exit_info_2 = svm->vcpu.arch.exception.payload; 794 else 795 svm->vmcb->control.exit_info_2 = svm->vcpu.arch.cr2; 796 } else if (nr == DB_VECTOR) { 797 /* See inject_pending_event. */ 798 kvm_deliver_exception_payload(&svm->vcpu); 799 if (svm->vcpu.arch.dr7 & DR7_GD) { 800 svm->vcpu.arch.dr7 &= ~DR7_GD; 801 kvm_update_dr7(&svm->vcpu); 802 } 803 } else 804 WARN_ON(svm->vcpu.arch.exception.has_payload); 805 806 nested_svm_vmexit(svm); 807 } 808 809 static void nested_svm_smi(struct vcpu_svm *svm) 810 { 811 svm->vmcb->control.exit_code = SVM_EXIT_SMI; 812 svm->vmcb->control.exit_info_1 = 0; 813 svm->vmcb->control.exit_info_2 = 0; 814 815 nested_svm_vmexit(svm); 816 } 817 818 static void nested_svm_nmi(struct vcpu_svm *svm) 819 { 820 svm->vmcb->control.exit_code = SVM_EXIT_NMI; 821 svm->vmcb->control.exit_info_1 = 0; 822 svm->vmcb->control.exit_info_2 = 0; 823 824 nested_svm_vmexit(svm); 825 } 826 827 static void nested_svm_intr(struct vcpu_svm *svm) 828 { 829 trace_kvm_nested_intr_vmexit(svm->vmcb->save.rip); 830 831 svm->vmcb->control.exit_code = SVM_EXIT_INTR; 832 svm->vmcb->control.exit_info_1 = 0; 833 svm->vmcb->control.exit_info_2 = 0; 834 835 nested_svm_vmexit(svm); 836 } 837 838 static inline bool nested_exit_on_init(struct vcpu_svm *svm) 839 { 840 return (svm->nested.ctl.intercept & (1ULL << INTERCEPT_INIT)); 841 } 842 843 static void nested_svm_init(struct vcpu_svm *svm) 844 { 845 svm->vmcb->control.exit_code = SVM_EXIT_INIT; 846 svm->vmcb->control.exit_info_1 = 0; 847 svm->vmcb->control.exit_info_2 = 0; 848 849 nested_svm_vmexit(svm); 850 } 851 852 853 static int svm_check_nested_events(struct kvm_vcpu *vcpu) 854 { 855 struct vcpu_svm *svm = to_svm(vcpu); 856 bool block_nested_events = 857 kvm_event_needs_reinjection(vcpu) || svm->nested.nested_run_pending; 858 struct kvm_lapic *apic = vcpu->arch.apic; 859 860 if (lapic_in_kernel(vcpu) && 861 test_bit(KVM_APIC_INIT, &apic->pending_events)) { 862 if (block_nested_events) 863 return -EBUSY; 864 if (!nested_exit_on_init(svm)) 865 return 0; 866 nested_svm_init(svm); 867 return 0; 868 } 869 870 if (vcpu->arch.exception.pending) { 871 if (block_nested_events) 872 return -EBUSY; 873 if (!nested_exit_on_exception(svm)) 874 return 0; 875 nested_svm_inject_exception_vmexit(svm); 876 return 0; 877 } 878 879 if (vcpu->arch.smi_pending && !svm_smi_blocked(vcpu)) { 880 if (block_nested_events) 881 return -EBUSY; 882 if (!nested_exit_on_smi(svm)) 883 return 0; 884 nested_svm_smi(svm); 885 return 0; 886 } 887 888 if (vcpu->arch.nmi_pending && !svm_nmi_blocked(vcpu)) { 889 if (block_nested_events) 890 return -EBUSY; 891 if (!nested_exit_on_nmi(svm)) 892 return 0; 893 nested_svm_nmi(svm); 894 return 0; 895 } 896 897 if (kvm_cpu_has_interrupt(vcpu) && !svm_interrupt_blocked(vcpu)) { 898 if (block_nested_events) 899 return -EBUSY; 900 if (!nested_exit_on_intr(svm)) 901 return 0; 902 nested_svm_intr(svm); 903 return 0; 904 } 905 906 return 0; 907 } 908 909 int nested_svm_exit_special(struct vcpu_svm *svm) 910 { 911 u32 exit_code = svm->vmcb->control.exit_code; 912 913 switch (exit_code) { 914 case SVM_EXIT_INTR: 915 case SVM_EXIT_NMI: 916 case SVM_EXIT_NPF: 917 return NESTED_EXIT_HOST; 918 case SVM_EXIT_EXCP_BASE ... SVM_EXIT_EXCP_BASE + 0x1f: { 919 u32 excp_bits = 1 << (exit_code - SVM_EXIT_EXCP_BASE); 920 921 if (get_host_vmcb(svm)->control.intercept_exceptions & excp_bits) 922 return NESTED_EXIT_HOST; 923 else if (exit_code == SVM_EXIT_EXCP_BASE + PF_VECTOR && 924 svm->vcpu.arch.apf.host_apf_flags) 925 /* Trap async PF even if not shadowing */ 926 return NESTED_EXIT_HOST; 927 break; 928 } 929 default: 930 break; 931 } 932 933 return NESTED_EXIT_CONTINUE; 934 } 935 936 static int svm_get_nested_state(struct kvm_vcpu *vcpu, 937 struct kvm_nested_state __user *user_kvm_nested_state, 938 u32 user_data_size) 939 { 940 struct vcpu_svm *svm; 941 struct kvm_nested_state kvm_state = { 942 .flags = 0, 943 .format = KVM_STATE_NESTED_FORMAT_SVM, 944 .size = sizeof(kvm_state), 945 }; 946 struct vmcb __user *user_vmcb = (struct vmcb __user *) 947 &user_kvm_nested_state->data.svm[0]; 948 949 if (!vcpu) 950 return kvm_state.size + KVM_STATE_NESTED_SVM_VMCB_SIZE; 951 952 svm = to_svm(vcpu); 953 954 if (user_data_size < kvm_state.size) 955 goto out; 956 957 /* First fill in the header and copy it out. */ 958 if (is_guest_mode(vcpu)) { 959 kvm_state.hdr.svm.vmcb_pa = svm->nested.vmcb; 960 kvm_state.size += KVM_STATE_NESTED_SVM_VMCB_SIZE; 961 kvm_state.flags |= KVM_STATE_NESTED_GUEST_MODE; 962 963 if (svm->nested.nested_run_pending) 964 kvm_state.flags |= KVM_STATE_NESTED_RUN_PENDING; 965 } 966 967 if (gif_set(svm)) 968 kvm_state.flags |= KVM_STATE_NESTED_GIF_SET; 969 970 if (copy_to_user(user_kvm_nested_state, &kvm_state, sizeof(kvm_state))) 971 return -EFAULT; 972 973 if (!is_guest_mode(vcpu)) 974 goto out; 975 976 /* 977 * Copy over the full size of the VMCB rather than just the size 978 * of the structs. 979 */ 980 if (clear_user(user_vmcb, KVM_STATE_NESTED_SVM_VMCB_SIZE)) 981 return -EFAULT; 982 if (copy_to_user(&user_vmcb->control, &svm->nested.ctl, 983 sizeof(user_vmcb->control))) 984 return -EFAULT; 985 if (copy_to_user(&user_vmcb->save, &svm->nested.hsave->save, 986 sizeof(user_vmcb->save))) 987 return -EFAULT; 988 989 out: 990 return kvm_state.size; 991 } 992 993 static int svm_set_nested_state(struct kvm_vcpu *vcpu, 994 struct kvm_nested_state __user *user_kvm_nested_state, 995 struct kvm_nested_state *kvm_state) 996 { 997 struct vcpu_svm *svm = to_svm(vcpu); 998 struct vmcb *hsave = svm->nested.hsave; 999 struct vmcb __user *user_vmcb = (struct vmcb __user *) 1000 &user_kvm_nested_state->data.svm[0]; 1001 struct vmcb_control_area ctl; 1002 struct vmcb_save_area save; 1003 u32 cr0; 1004 1005 if (kvm_state->format != KVM_STATE_NESTED_FORMAT_SVM) 1006 return -EINVAL; 1007 1008 if (kvm_state->flags & ~(KVM_STATE_NESTED_GUEST_MODE | 1009 KVM_STATE_NESTED_RUN_PENDING | 1010 KVM_STATE_NESTED_GIF_SET)) 1011 return -EINVAL; 1012 1013 /* 1014 * If in guest mode, vcpu->arch.efer actually refers to the L2 guest's 1015 * EFER.SVME, but EFER.SVME still has to be 1 for VMRUN to succeed. 1016 */ 1017 if (!(vcpu->arch.efer & EFER_SVME)) { 1018 /* GIF=1 and no guest mode are required if SVME=0. */ 1019 if (kvm_state->flags != KVM_STATE_NESTED_GIF_SET) 1020 return -EINVAL; 1021 } 1022 1023 /* SMM temporarily disables SVM, so we cannot be in guest mode. */ 1024 if (is_smm(vcpu) && (kvm_state->flags & KVM_STATE_NESTED_GUEST_MODE)) 1025 return -EINVAL; 1026 1027 if (!(kvm_state->flags & KVM_STATE_NESTED_GUEST_MODE)) { 1028 svm_leave_nested(svm); 1029 goto out_set_gif; 1030 } 1031 1032 if (!page_address_valid(vcpu, kvm_state->hdr.svm.vmcb_pa)) 1033 return -EINVAL; 1034 if (kvm_state->size < sizeof(*kvm_state) + KVM_STATE_NESTED_SVM_VMCB_SIZE) 1035 return -EINVAL; 1036 if (copy_from_user(&ctl, &user_vmcb->control, sizeof(ctl))) 1037 return -EFAULT; 1038 if (copy_from_user(&save, &user_vmcb->save, sizeof(save))) 1039 return -EFAULT; 1040 1041 if (!nested_vmcb_check_controls(&ctl)) 1042 return -EINVAL; 1043 1044 /* 1045 * Processor state contains L2 state. Check that it is 1046 * valid for guest mode (see nested_vmcb_checks). 1047 */ 1048 cr0 = kvm_read_cr0(vcpu); 1049 if (((cr0 & X86_CR0_CD) == 0) && (cr0 & X86_CR0_NW)) 1050 return -EINVAL; 1051 1052 /* 1053 * Validate host state saved from before VMRUN (see 1054 * nested_svm_check_permissions). 1055 * TODO: validate reserved bits for all saved state. 1056 */ 1057 if (!(save.cr0 & X86_CR0_PG)) 1058 return -EINVAL; 1059 1060 /* 1061 * All checks done, we can enter guest mode. L1 control fields 1062 * come from the nested save state. Guest state is already 1063 * in the registers, the save area of the nested state instead 1064 * contains saved L1 state. 1065 */ 1066 copy_vmcb_control_area(&hsave->control, &svm->vmcb->control); 1067 hsave->save = save; 1068 1069 svm->nested.vmcb = kvm_state->hdr.svm.vmcb_pa; 1070 load_nested_vmcb_control(svm, &ctl); 1071 nested_prepare_vmcb_control(svm); 1072 1073 out_set_gif: 1074 svm_set_gif(svm, !!(kvm_state->flags & KVM_STATE_NESTED_GIF_SET)); 1075 return 0; 1076 } 1077 1078 struct kvm_x86_nested_ops svm_nested_ops = { 1079 .check_events = svm_check_nested_events, 1080 .get_state = svm_get_nested_state, 1081 .set_state = svm_set_nested_state, 1082 }; 1083