1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Kernel-based Virtual Machine driver for Linux 4 * 5 * AMD SVM-SEV support 6 * 7 * Copyright 2010 Red Hat, Inc. and/or its affiliates. 8 */ 9 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 10 11 #include <linux/kvm_types.h> 12 #include <linux/kvm_host.h> 13 #include <linux/kernel.h> 14 #include <linux/highmem.h> 15 #include <linux/psp.h> 16 #include <linux/psp-sev.h> 17 #include <linux/pagemap.h> 18 #include <linux/swap.h> 19 #include <linux/misc_cgroup.h> 20 #include <linux/processor.h> 21 #include <linux/trace_events.h> 22 23 #include <asm/pkru.h> 24 #include <asm/trapnr.h> 25 #include <asm/fpu/xcr.h> 26 #include <asm/fpu/xstate.h> 27 #include <asm/debugreg.h> 28 29 #include "mmu.h" 30 #include "x86.h" 31 #include "svm.h" 32 #include "svm_ops.h" 33 #include "cpuid.h" 34 #include "trace.h" 35 36 #define GHCB_VERSION_MAX 2ULL 37 #define GHCB_VERSION_DEFAULT 2ULL 38 #define GHCB_VERSION_MIN 1ULL 39 40 #define GHCB_HV_FT_SUPPORTED GHCB_HV_FT_SNP 41 42 /* enable/disable SEV support */ 43 static bool sev_enabled = true; 44 module_param_named(sev, sev_enabled, bool, 0444); 45 46 /* enable/disable SEV-ES support */ 47 static bool sev_es_enabled = true; 48 module_param_named(sev_es, sev_es_enabled, bool, 0444); 49 50 /* enable/disable SEV-ES DebugSwap support */ 51 static bool sev_es_debug_swap_enabled = true; 52 module_param_named(debug_swap, sev_es_debug_swap_enabled, bool, 0444); 53 static u64 sev_supported_vmsa_features; 54 55 #define AP_RESET_HOLD_NONE 0 56 #define AP_RESET_HOLD_NAE_EVENT 1 57 #define AP_RESET_HOLD_MSR_PROTO 2 58 59 static u8 sev_enc_bit; 60 static DECLARE_RWSEM(sev_deactivate_lock); 61 static DEFINE_MUTEX(sev_bitmap_lock); 62 unsigned int max_sev_asid; 63 static unsigned int min_sev_asid; 64 static unsigned long sev_me_mask; 65 static unsigned int nr_asids; 66 static unsigned long *sev_asid_bitmap; 67 static unsigned long *sev_reclaim_asid_bitmap; 68 69 struct enc_region { 70 struct list_head list; 71 unsigned long npages; 72 struct page **pages; 73 unsigned long uaddr; 74 unsigned long size; 75 }; 76 77 /* Called with the sev_bitmap_lock held, or on shutdown */ 78 static int sev_flush_asids(unsigned int min_asid, unsigned int max_asid) 79 { 80 int ret, error = 0; 81 unsigned int asid; 82 83 /* Check if there are any ASIDs to reclaim before performing a flush */ 84 asid = find_next_bit(sev_reclaim_asid_bitmap, nr_asids, min_asid); 85 if (asid > max_asid) 86 return -EBUSY; 87 88 /* 89 * DEACTIVATE will clear the WBINVD indicator causing DF_FLUSH to fail, 90 * so it must be guarded. 91 */ 92 down_write(&sev_deactivate_lock); 93 94 wbinvd_on_all_cpus(); 95 ret = sev_guest_df_flush(&error); 96 97 up_write(&sev_deactivate_lock); 98 99 if (ret) 100 pr_err("SEV: DF_FLUSH failed, ret=%d, error=%#x\n", ret, error); 101 102 return ret; 103 } 104 105 static inline bool is_mirroring_enc_context(struct kvm *kvm) 106 { 107 return !!to_kvm_sev_info(kvm)->enc_context_owner; 108 } 109 110 static bool sev_vcpu_has_debug_swap(struct vcpu_svm *svm) 111 { 112 struct kvm_vcpu *vcpu = &svm->vcpu; 113 struct kvm_sev_info *sev = &to_kvm_svm(vcpu->kvm)->sev_info; 114 115 return sev->vmsa_features & SVM_SEV_FEAT_DEBUG_SWAP; 116 } 117 118 /* Must be called with the sev_bitmap_lock held */ 119 static bool __sev_recycle_asids(unsigned int min_asid, unsigned int max_asid) 120 { 121 if (sev_flush_asids(min_asid, max_asid)) 122 return false; 123 124 /* The flush process will flush all reclaimable SEV and SEV-ES ASIDs */ 125 bitmap_xor(sev_asid_bitmap, sev_asid_bitmap, sev_reclaim_asid_bitmap, 126 nr_asids); 127 bitmap_zero(sev_reclaim_asid_bitmap, nr_asids); 128 129 return true; 130 } 131 132 static int sev_misc_cg_try_charge(struct kvm_sev_info *sev) 133 { 134 enum misc_res_type type = sev->es_active ? MISC_CG_RES_SEV_ES : MISC_CG_RES_SEV; 135 return misc_cg_try_charge(type, sev->misc_cg, 1); 136 } 137 138 static void sev_misc_cg_uncharge(struct kvm_sev_info *sev) 139 { 140 enum misc_res_type type = sev->es_active ? MISC_CG_RES_SEV_ES : MISC_CG_RES_SEV; 141 misc_cg_uncharge(type, sev->misc_cg, 1); 142 } 143 144 static int sev_asid_new(struct kvm_sev_info *sev) 145 { 146 /* 147 * SEV-enabled guests must use asid from min_sev_asid to max_sev_asid. 148 * SEV-ES-enabled guest can use from 1 to min_sev_asid - 1. 149 * Note: min ASID can end up larger than the max if basic SEV support is 150 * effectively disabled by disallowing use of ASIDs for SEV guests. 151 */ 152 unsigned int min_asid = sev->es_active ? 1 : min_sev_asid; 153 unsigned int max_asid = sev->es_active ? min_sev_asid - 1 : max_sev_asid; 154 unsigned int asid; 155 bool retry = true; 156 int ret; 157 158 if (min_asid > max_asid) 159 return -ENOTTY; 160 161 WARN_ON(sev->misc_cg); 162 sev->misc_cg = get_current_misc_cg(); 163 ret = sev_misc_cg_try_charge(sev); 164 if (ret) { 165 put_misc_cg(sev->misc_cg); 166 sev->misc_cg = NULL; 167 return ret; 168 } 169 170 mutex_lock(&sev_bitmap_lock); 171 172 again: 173 asid = find_next_zero_bit(sev_asid_bitmap, max_asid + 1, min_asid); 174 if (asid > max_asid) { 175 if (retry && __sev_recycle_asids(min_asid, max_asid)) { 176 retry = false; 177 goto again; 178 } 179 mutex_unlock(&sev_bitmap_lock); 180 ret = -EBUSY; 181 goto e_uncharge; 182 } 183 184 __set_bit(asid, sev_asid_bitmap); 185 186 mutex_unlock(&sev_bitmap_lock); 187 188 sev->asid = asid; 189 return 0; 190 e_uncharge: 191 sev_misc_cg_uncharge(sev); 192 put_misc_cg(sev->misc_cg); 193 sev->misc_cg = NULL; 194 return ret; 195 } 196 197 static unsigned int sev_get_asid(struct kvm *kvm) 198 { 199 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 200 201 return sev->asid; 202 } 203 204 static void sev_asid_free(struct kvm_sev_info *sev) 205 { 206 struct svm_cpu_data *sd; 207 int cpu; 208 209 mutex_lock(&sev_bitmap_lock); 210 211 __set_bit(sev->asid, sev_reclaim_asid_bitmap); 212 213 for_each_possible_cpu(cpu) { 214 sd = per_cpu_ptr(&svm_data, cpu); 215 sd->sev_vmcbs[sev->asid] = NULL; 216 } 217 218 mutex_unlock(&sev_bitmap_lock); 219 220 sev_misc_cg_uncharge(sev); 221 put_misc_cg(sev->misc_cg); 222 sev->misc_cg = NULL; 223 } 224 225 static void sev_decommission(unsigned int handle) 226 { 227 struct sev_data_decommission decommission; 228 229 if (!handle) 230 return; 231 232 decommission.handle = handle; 233 sev_guest_decommission(&decommission, NULL); 234 } 235 236 static void sev_unbind_asid(struct kvm *kvm, unsigned int handle) 237 { 238 struct sev_data_deactivate deactivate; 239 240 if (!handle) 241 return; 242 243 deactivate.handle = handle; 244 245 /* Guard DEACTIVATE against WBINVD/DF_FLUSH used in ASID recycling */ 246 down_read(&sev_deactivate_lock); 247 sev_guest_deactivate(&deactivate, NULL); 248 up_read(&sev_deactivate_lock); 249 250 sev_decommission(handle); 251 } 252 253 static int __sev_guest_init(struct kvm *kvm, struct kvm_sev_cmd *argp, 254 struct kvm_sev_init *data, 255 unsigned long vm_type) 256 { 257 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 258 struct sev_platform_init_args init_args = {0}; 259 bool es_active = vm_type != KVM_X86_SEV_VM; 260 u64 valid_vmsa_features = es_active ? sev_supported_vmsa_features : 0; 261 int ret; 262 263 if (kvm->created_vcpus) 264 return -EINVAL; 265 266 if (data->flags) 267 return -EINVAL; 268 269 if (data->vmsa_features & ~valid_vmsa_features) 270 return -EINVAL; 271 272 if (data->ghcb_version > GHCB_VERSION_MAX || (!es_active && data->ghcb_version)) 273 return -EINVAL; 274 275 if (unlikely(sev->active)) 276 return -EINVAL; 277 278 sev->active = true; 279 sev->es_active = es_active; 280 sev->vmsa_features = data->vmsa_features; 281 sev->ghcb_version = data->ghcb_version; 282 283 /* 284 * Currently KVM supports the full range of mandatory features defined 285 * by version 2 of the GHCB protocol, so default to that for SEV-ES 286 * guests created via KVM_SEV_INIT2. 287 */ 288 if (sev->es_active && !sev->ghcb_version) 289 sev->ghcb_version = GHCB_VERSION_DEFAULT; 290 291 ret = sev_asid_new(sev); 292 if (ret) 293 goto e_no_asid; 294 295 init_args.probe = false; 296 ret = sev_platform_init(&init_args); 297 if (ret) 298 goto e_free; 299 300 INIT_LIST_HEAD(&sev->regions_list); 301 INIT_LIST_HEAD(&sev->mirror_vms); 302 sev->need_init = false; 303 304 kvm_set_apicv_inhibit(kvm, APICV_INHIBIT_REASON_SEV); 305 306 return 0; 307 308 e_free: 309 argp->error = init_args.error; 310 sev_asid_free(sev); 311 sev->asid = 0; 312 e_no_asid: 313 sev->vmsa_features = 0; 314 sev->es_active = false; 315 sev->active = false; 316 return ret; 317 } 318 319 static int sev_guest_init(struct kvm *kvm, struct kvm_sev_cmd *argp) 320 { 321 struct kvm_sev_init data = { 322 .vmsa_features = 0, 323 .ghcb_version = 0, 324 }; 325 unsigned long vm_type; 326 327 if (kvm->arch.vm_type != KVM_X86_DEFAULT_VM) 328 return -EINVAL; 329 330 vm_type = (argp->id == KVM_SEV_INIT ? KVM_X86_SEV_VM : KVM_X86_SEV_ES_VM); 331 332 /* 333 * KVM_SEV_ES_INIT has been deprecated by KVM_SEV_INIT2, so it will 334 * continue to only ever support the minimal GHCB protocol version. 335 */ 336 if (vm_type == KVM_X86_SEV_ES_VM) 337 data.ghcb_version = GHCB_VERSION_MIN; 338 339 return __sev_guest_init(kvm, argp, &data, vm_type); 340 } 341 342 static int sev_guest_init2(struct kvm *kvm, struct kvm_sev_cmd *argp) 343 { 344 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 345 struct kvm_sev_init data; 346 347 if (!sev->need_init) 348 return -EINVAL; 349 350 if (kvm->arch.vm_type != KVM_X86_SEV_VM && 351 kvm->arch.vm_type != KVM_X86_SEV_ES_VM) 352 return -EINVAL; 353 354 if (copy_from_user(&data, u64_to_user_ptr(argp->data), sizeof(data))) 355 return -EFAULT; 356 357 return __sev_guest_init(kvm, argp, &data, kvm->arch.vm_type); 358 } 359 360 static int sev_bind_asid(struct kvm *kvm, unsigned int handle, int *error) 361 { 362 unsigned int asid = sev_get_asid(kvm); 363 struct sev_data_activate activate; 364 int ret; 365 366 /* activate ASID on the given handle */ 367 activate.handle = handle; 368 activate.asid = asid; 369 ret = sev_guest_activate(&activate, error); 370 371 return ret; 372 } 373 374 static int __sev_issue_cmd(int fd, int id, void *data, int *error) 375 { 376 struct fd f; 377 int ret; 378 379 f = fdget(fd); 380 if (!f.file) 381 return -EBADF; 382 383 ret = sev_issue_cmd_external_user(f.file, id, data, error); 384 385 fdput(f); 386 return ret; 387 } 388 389 static int sev_issue_cmd(struct kvm *kvm, int id, void *data, int *error) 390 { 391 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 392 393 return __sev_issue_cmd(sev->fd, id, data, error); 394 } 395 396 static int sev_launch_start(struct kvm *kvm, struct kvm_sev_cmd *argp) 397 { 398 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 399 struct sev_data_launch_start start; 400 struct kvm_sev_launch_start params; 401 void *dh_blob, *session_blob; 402 int *error = &argp->error; 403 int ret; 404 405 if (!sev_guest(kvm)) 406 return -ENOTTY; 407 408 if (copy_from_user(¶ms, u64_to_user_ptr(argp->data), sizeof(params))) 409 return -EFAULT; 410 411 memset(&start, 0, sizeof(start)); 412 413 dh_blob = NULL; 414 if (params.dh_uaddr) { 415 dh_blob = psp_copy_user_blob(params.dh_uaddr, params.dh_len); 416 if (IS_ERR(dh_blob)) 417 return PTR_ERR(dh_blob); 418 419 start.dh_cert_address = __sme_set(__pa(dh_blob)); 420 start.dh_cert_len = params.dh_len; 421 } 422 423 session_blob = NULL; 424 if (params.session_uaddr) { 425 session_blob = psp_copy_user_blob(params.session_uaddr, params.session_len); 426 if (IS_ERR(session_blob)) { 427 ret = PTR_ERR(session_blob); 428 goto e_free_dh; 429 } 430 431 start.session_address = __sme_set(__pa(session_blob)); 432 start.session_len = params.session_len; 433 } 434 435 start.handle = params.handle; 436 start.policy = params.policy; 437 438 /* create memory encryption context */ 439 ret = __sev_issue_cmd(argp->sev_fd, SEV_CMD_LAUNCH_START, &start, error); 440 if (ret) 441 goto e_free_session; 442 443 /* Bind ASID to this guest */ 444 ret = sev_bind_asid(kvm, start.handle, error); 445 if (ret) { 446 sev_decommission(start.handle); 447 goto e_free_session; 448 } 449 450 /* return handle to userspace */ 451 params.handle = start.handle; 452 if (copy_to_user(u64_to_user_ptr(argp->data), ¶ms, sizeof(params))) { 453 sev_unbind_asid(kvm, start.handle); 454 ret = -EFAULT; 455 goto e_free_session; 456 } 457 458 sev->handle = start.handle; 459 sev->fd = argp->sev_fd; 460 461 e_free_session: 462 kfree(session_blob); 463 e_free_dh: 464 kfree(dh_blob); 465 return ret; 466 } 467 468 static struct page **sev_pin_memory(struct kvm *kvm, unsigned long uaddr, 469 unsigned long ulen, unsigned long *n, 470 int write) 471 { 472 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 473 unsigned long npages, size; 474 int npinned; 475 unsigned long locked, lock_limit; 476 struct page **pages; 477 unsigned long first, last; 478 int ret; 479 480 lockdep_assert_held(&kvm->lock); 481 482 if (ulen == 0 || uaddr + ulen < uaddr) 483 return ERR_PTR(-EINVAL); 484 485 /* Calculate number of pages. */ 486 first = (uaddr & PAGE_MASK) >> PAGE_SHIFT; 487 last = ((uaddr + ulen - 1) & PAGE_MASK) >> PAGE_SHIFT; 488 npages = (last - first + 1); 489 490 locked = sev->pages_locked + npages; 491 lock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT; 492 if (locked > lock_limit && !capable(CAP_IPC_LOCK)) { 493 pr_err("SEV: %lu locked pages exceed the lock limit of %lu.\n", locked, lock_limit); 494 return ERR_PTR(-ENOMEM); 495 } 496 497 if (WARN_ON_ONCE(npages > INT_MAX)) 498 return ERR_PTR(-EINVAL); 499 500 /* Avoid using vmalloc for smaller buffers. */ 501 size = npages * sizeof(struct page *); 502 if (size > PAGE_SIZE) 503 pages = __vmalloc(size, GFP_KERNEL_ACCOUNT); 504 else 505 pages = kmalloc(size, GFP_KERNEL_ACCOUNT); 506 507 if (!pages) 508 return ERR_PTR(-ENOMEM); 509 510 /* Pin the user virtual address. */ 511 npinned = pin_user_pages_fast(uaddr, npages, write ? FOLL_WRITE : 0, pages); 512 if (npinned != npages) { 513 pr_err("SEV: Failure locking %lu pages.\n", npages); 514 ret = -ENOMEM; 515 goto err; 516 } 517 518 *n = npages; 519 sev->pages_locked = locked; 520 521 return pages; 522 523 err: 524 if (npinned > 0) 525 unpin_user_pages(pages, npinned); 526 527 kvfree(pages); 528 return ERR_PTR(ret); 529 } 530 531 static void sev_unpin_memory(struct kvm *kvm, struct page **pages, 532 unsigned long npages) 533 { 534 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 535 536 unpin_user_pages(pages, npages); 537 kvfree(pages); 538 sev->pages_locked -= npages; 539 } 540 541 static void sev_clflush_pages(struct page *pages[], unsigned long npages) 542 { 543 uint8_t *page_virtual; 544 unsigned long i; 545 546 if (this_cpu_has(X86_FEATURE_SME_COHERENT) || npages == 0 || 547 pages == NULL) 548 return; 549 550 for (i = 0; i < npages; i++) { 551 page_virtual = kmap_local_page(pages[i]); 552 clflush_cache_range(page_virtual, PAGE_SIZE); 553 kunmap_local(page_virtual); 554 cond_resched(); 555 } 556 } 557 558 static unsigned long get_num_contig_pages(unsigned long idx, 559 struct page **inpages, unsigned long npages) 560 { 561 unsigned long paddr, next_paddr; 562 unsigned long i = idx + 1, pages = 1; 563 564 /* find the number of contiguous pages starting from idx */ 565 paddr = __sme_page_pa(inpages[idx]); 566 while (i < npages) { 567 next_paddr = __sme_page_pa(inpages[i++]); 568 if ((paddr + PAGE_SIZE) == next_paddr) { 569 pages++; 570 paddr = next_paddr; 571 continue; 572 } 573 break; 574 } 575 576 return pages; 577 } 578 579 static int sev_launch_update_data(struct kvm *kvm, struct kvm_sev_cmd *argp) 580 { 581 unsigned long vaddr, vaddr_end, next_vaddr, npages, pages, size, i; 582 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 583 struct kvm_sev_launch_update_data params; 584 struct sev_data_launch_update_data data; 585 struct page **inpages; 586 int ret; 587 588 if (!sev_guest(kvm)) 589 return -ENOTTY; 590 591 if (copy_from_user(¶ms, u64_to_user_ptr(argp->data), sizeof(params))) 592 return -EFAULT; 593 594 vaddr = params.uaddr; 595 size = params.len; 596 vaddr_end = vaddr + size; 597 598 /* Lock the user memory. */ 599 inpages = sev_pin_memory(kvm, vaddr, size, &npages, 1); 600 if (IS_ERR(inpages)) 601 return PTR_ERR(inpages); 602 603 /* 604 * Flush (on non-coherent CPUs) before LAUNCH_UPDATE encrypts pages in 605 * place; the cache may contain the data that was written unencrypted. 606 */ 607 sev_clflush_pages(inpages, npages); 608 609 data.reserved = 0; 610 data.handle = sev->handle; 611 612 for (i = 0; vaddr < vaddr_end; vaddr = next_vaddr, i += pages) { 613 int offset, len; 614 615 /* 616 * If the user buffer is not page-aligned, calculate the offset 617 * within the page. 618 */ 619 offset = vaddr & (PAGE_SIZE - 1); 620 621 /* Calculate the number of pages that can be encrypted in one go. */ 622 pages = get_num_contig_pages(i, inpages, npages); 623 624 len = min_t(size_t, ((pages * PAGE_SIZE) - offset), size); 625 626 data.len = len; 627 data.address = __sme_page_pa(inpages[i]) + offset; 628 ret = sev_issue_cmd(kvm, SEV_CMD_LAUNCH_UPDATE_DATA, &data, &argp->error); 629 if (ret) 630 goto e_unpin; 631 632 size -= len; 633 next_vaddr = vaddr + len; 634 } 635 636 e_unpin: 637 /* content of memory is updated, mark pages dirty */ 638 for (i = 0; i < npages; i++) { 639 set_page_dirty_lock(inpages[i]); 640 mark_page_accessed(inpages[i]); 641 } 642 /* unlock the user pages */ 643 sev_unpin_memory(kvm, inpages, npages); 644 return ret; 645 } 646 647 static int sev_es_sync_vmsa(struct vcpu_svm *svm) 648 { 649 struct kvm_vcpu *vcpu = &svm->vcpu; 650 struct kvm_sev_info *sev = &to_kvm_svm(vcpu->kvm)->sev_info; 651 struct sev_es_save_area *save = svm->sev_es.vmsa; 652 struct xregs_state *xsave; 653 const u8 *s; 654 u8 *d; 655 int i; 656 657 /* Check some debug related fields before encrypting the VMSA */ 658 if (svm->vcpu.guest_debug || (svm->vmcb->save.dr7 & ~DR7_FIXED_1)) 659 return -EINVAL; 660 661 /* 662 * SEV-ES will use a VMSA that is pointed to by the VMCB, not 663 * the traditional VMSA that is part of the VMCB. Copy the 664 * traditional VMSA as it has been built so far (in prep 665 * for LAUNCH_UPDATE_VMSA) to be the initial SEV-ES state. 666 */ 667 memcpy(save, &svm->vmcb->save, sizeof(svm->vmcb->save)); 668 669 /* Sync registgers */ 670 save->rax = svm->vcpu.arch.regs[VCPU_REGS_RAX]; 671 save->rbx = svm->vcpu.arch.regs[VCPU_REGS_RBX]; 672 save->rcx = svm->vcpu.arch.regs[VCPU_REGS_RCX]; 673 save->rdx = svm->vcpu.arch.regs[VCPU_REGS_RDX]; 674 save->rsp = svm->vcpu.arch.regs[VCPU_REGS_RSP]; 675 save->rbp = svm->vcpu.arch.regs[VCPU_REGS_RBP]; 676 save->rsi = svm->vcpu.arch.regs[VCPU_REGS_RSI]; 677 save->rdi = svm->vcpu.arch.regs[VCPU_REGS_RDI]; 678 #ifdef CONFIG_X86_64 679 save->r8 = svm->vcpu.arch.regs[VCPU_REGS_R8]; 680 save->r9 = svm->vcpu.arch.regs[VCPU_REGS_R9]; 681 save->r10 = svm->vcpu.arch.regs[VCPU_REGS_R10]; 682 save->r11 = svm->vcpu.arch.regs[VCPU_REGS_R11]; 683 save->r12 = svm->vcpu.arch.regs[VCPU_REGS_R12]; 684 save->r13 = svm->vcpu.arch.regs[VCPU_REGS_R13]; 685 save->r14 = svm->vcpu.arch.regs[VCPU_REGS_R14]; 686 save->r15 = svm->vcpu.arch.regs[VCPU_REGS_R15]; 687 #endif 688 save->rip = svm->vcpu.arch.regs[VCPU_REGS_RIP]; 689 690 /* Sync some non-GPR registers before encrypting */ 691 save->xcr0 = svm->vcpu.arch.xcr0; 692 save->pkru = svm->vcpu.arch.pkru; 693 save->xss = svm->vcpu.arch.ia32_xss; 694 save->dr6 = svm->vcpu.arch.dr6; 695 696 save->sev_features = sev->vmsa_features; 697 698 /* 699 * Skip FPU and AVX setup with KVM_SEV_ES_INIT to avoid 700 * breaking older measurements. 701 */ 702 if (vcpu->kvm->arch.vm_type != KVM_X86_DEFAULT_VM) { 703 xsave = &vcpu->arch.guest_fpu.fpstate->regs.xsave; 704 save->x87_dp = xsave->i387.rdp; 705 save->mxcsr = xsave->i387.mxcsr; 706 save->x87_ftw = xsave->i387.twd; 707 save->x87_fsw = xsave->i387.swd; 708 save->x87_fcw = xsave->i387.cwd; 709 save->x87_fop = xsave->i387.fop; 710 save->x87_ds = 0; 711 save->x87_cs = 0; 712 save->x87_rip = xsave->i387.rip; 713 714 for (i = 0; i < 8; i++) { 715 /* 716 * The format of the x87 save area is undocumented and 717 * definitely not what you would expect. It consists of 718 * an 8*8 bytes area with bytes 0-7, and an 8*2 bytes 719 * area with bytes 8-9 of each register. 720 */ 721 d = save->fpreg_x87 + i * 8; 722 s = ((u8 *)xsave->i387.st_space) + i * 16; 723 memcpy(d, s, 8); 724 save->fpreg_x87[64 + i * 2] = s[8]; 725 save->fpreg_x87[64 + i * 2 + 1] = s[9]; 726 } 727 memcpy(save->fpreg_xmm, xsave->i387.xmm_space, 256); 728 729 s = get_xsave_addr(xsave, XFEATURE_YMM); 730 if (s) 731 memcpy(save->fpreg_ymm, s, 256); 732 else 733 memset(save->fpreg_ymm, 0, 256); 734 } 735 736 pr_debug("Virtual Machine Save Area (VMSA):\n"); 737 print_hex_dump_debug("", DUMP_PREFIX_NONE, 16, 1, save, sizeof(*save), false); 738 739 return 0; 740 } 741 742 static int __sev_launch_update_vmsa(struct kvm *kvm, struct kvm_vcpu *vcpu, 743 int *error) 744 { 745 struct sev_data_launch_update_vmsa vmsa; 746 struct vcpu_svm *svm = to_svm(vcpu); 747 int ret; 748 749 if (vcpu->guest_debug) { 750 pr_warn_once("KVM_SET_GUEST_DEBUG for SEV-ES guest is not supported"); 751 return -EINVAL; 752 } 753 754 /* Perform some pre-encryption checks against the VMSA */ 755 ret = sev_es_sync_vmsa(svm); 756 if (ret) 757 return ret; 758 759 /* 760 * The LAUNCH_UPDATE_VMSA command will perform in-place encryption of 761 * the VMSA memory content (i.e it will write the same memory region 762 * with the guest's key), so invalidate it first. 763 */ 764 clflush_cache_range(svm->sev_es.vmsa, PAGE_SIZE); 765 766 vmsa.reserved = 0; 767 vmsa.handle = to_kvm_sev_info(kvm)->handle; 768 vmsa.address = __sme_pa(svm->sev_es.vmsa); 769 vmsa.len = PAGE_SIZE; 770 ret = sev_issue_cmd(kvm, SEV_CMD_LAUNCH_UPDATE_VMSA, &vmsa, error); 771 if (ret) 772 return ret; 773 774 /* 775 * SEV-ES guests maintain an encrypted version of their FPU 776 * state which is restored and saved on VMRUN and VMEXIT. 777 * Mark vcpu->arch.guest_fpu->fpstate as scratch so it won't 778 * do xsave/xrstor on it. 779 */ 780 fpstate_set_confidential(&vcpu->arch.guest_fpu); 781 vcpu->arch.guest_state_protected = true; 782 return 0; 783 } 784 785 static int sev_launch_update_vmsa(struct kvm *kvm, struct kvm_sev_cmd *argp) 786 { 787 struct kvm_vcpu *vcpu; 788 unsigned long i; 789 int ret; 790 791 if (!sev_es_guest(kvm)) 792 return -ENOTTY; 793 794 kvm_for_each_vcpu(i, vcpu, kvm) { 795 ret = mutex_lock_killable(&vcpu->mutex); 796 if (ret) 797 return ret; 798 799 ret = __sev_launch_update_vmsa(kvm, vcpu, &argp->error); 800 801 mutex_unlock(&vcpu->mutex); 802 if (ret) 803 return ret; 804 } 805 806 return 0; 807 } 808 809 static int sev_launch_measure(struct kvm *kvm, struct kvm_sev_cmd *argp) 810 { 811 void __user *measure = u64_to_user_ptr(argp->data); 812 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 813 struct sev_data_launch_measure data; 814 struct kvm_sev_launch_measure params; 815 void __user *p = NULL; 816 void *blob = NULL; 817 int ret; 818 819 if (!sev_guest(kvm)) 820 return -ENOTTY; 821 822 if (copy_from_user(¶ms, measure, sizeof(params))) 823 return -EFAULT; 824 825 memset(&data, 0, sizeof(data)); 826 827 /* User wants to query the blob length */ 828 if (!params.len) 829 goto cmd; 830 831 p = u64_to_user_ptr(params.uaddr); 832 if (p) { 833 if (params.len > SEV_FW_BLOB_MAX_SIZE) 834 return -EINVAL; 835 836 blob = kzalloc(params.len, GFP_KERNEL_ACCOUNT); 837 if (!blob) 838 return -ENOMEM; 839 840 data.address = __psp_pa(blob); 841 data.len = params.len; 842 } 843 844 cmd: 845 data.handle = sev->handle; 846 ret = sev_issue_cmd(kvm, SEV_CMD_LAUNCH_MEASURE, &data, &argp->error); 847 848 /* 849 * If we query the session length, FW responded with expected data. 850 */ 851 if (!params.len) 852 goto done; 853 854 if (ret) 855 goto e_free_blob; 856 857 if (blob) { 858 if (copy_to_user(p, blob, params.len)) 859 ret = -EFAULT; 860 } 861 862 done: 863 params.len = data.len; 864 if (copy_to_user(measure, ¶ms, sizeof(params))) 865 ret = -EFAULT; 866 e_free_blob: 867 kfree(blob); 868 return ret; 869 } 870 871 static int sev_launch_finish(struct kvm *kvm, struct kvm_sev_cmd *argp) 872 { 873 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 874 struct sev_data_launch_finish data; 875 876 if (!sev_guest(kvm)) 877 return -ENOTTY; 878 879 data.handle = sev->handle; 880 return sev_issue_cmd(kvm, SEV_CMD_LAUNCH_FINISH, &data, &argp->error); 881 } 882 883 static int sev_guest_status(struct kvm *kvm, struct kvm_sev_cmd *argp) 884 { 885 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 886 struct kvm_sev_guest_status params; 887 struct sev_data_guest_status data; 888 int ret; 889 890 if (!sev_guest(kvm)) 891 return -ENOTTY; 892 893 memset(&data, 0, sizeof(data)); 894 895 data.handle = sev->handle; 896 ret = sev_issue_cmd(kvm, SEV_CMD_GUEST_STATUS, &data, &argp->error); 897 if (ret) 898 return ret; 899 900 params.policy = data.policy; 901 params.state = data.state; 902 params.handle = data.handle; 903 904 if (copy_to_user(u64_to_user_ptr(argp->data), ¶ms, sizeof(params))) 905 ret = -EFAULT; 906 907 return ret; 908 } 909 910 static int __sev_issue_dbg_cmd(struct kvm *kvm, unsigned long src, 911 unsigned long dst, int size, 912 int *error, bool enc) 913 { 914 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 915 struct sev_data_dbg data; 916 917 data.reserved = 0; 918 data.handle = sev->handle; 919 data.dst_addr = dst; 920 data.src_addr = src; 921 data.len = size; 922 923 return sev_issue_cmd(kvm, 924 enc ? SEV_CMD_DBG_ENCRYPT : SEV_CMD_DBG_DECRYPT, 925 &data, error); 926 } 927 928 static int __sev_dbg_decrypt(struct kvm *kvm, unsigned long src_paddr, 929 unsigned long dst_paddr, int sz, int *err) 930 { 931 int offset; 932 933 /* 934 * Its safe to read more than we are asked, caller should ensure that 935 * destination has enough space. 936 */ 937 offset = src_paddr & 15; 938 src_paddr = round_down(src_paddr, 16); 939 sz = round_up(sz + offset, 16); 940 941 return __sev_issue_dbg_cmd(kvm, src_paddr, dst_paddr, sz, err, false); 942 } 943 944 static int __sev_dbg_decrypt_user(struct kvm *kvm, unsigned long paddr, 945 void __user *dst_uaddr, 946 unsigned long dst_paddr, 947 int size, int *err) 948 { 949 struct page *tpage = NULL; 950 int ret, offset; 951 952 /* if inputs are not 16-byte then use intermediate buffer */ 953 if (!IS_ALIGNED(dst_paddr, 16) || 954 !IS_ALIGNED(paddr, 16) || 955 !IS_ALIGNED(size, 16)) { 956 tpage = (void *)alloc_page(GFP_KERNEL_ACCOUNT | __GFP_ZERO); 957 if (!tpage) 958 return -ENOMEM; 959 960 dst_paddr = __sme_page_pa(tpage); 961 } 962 963 ret = __sev_dbg_decrypt(kvm, paddr, dst_paddr, size, err); 964 if (ret) 965 goto e_free; 966 967 if (tpage) { 968 offset = paddr & 15; 969 if (copy_to_user(dst_uaddr, page_address(tpage) + offset, size)) 970 ret = -EFAULT; 971 } 972 973 e_free: 974 if (tpage) 975 __free_page(tpage); 976 977 return ret; 978 } 979 980 static int __sev_dbg_encrypt_user(struct kvm *kvm, unsigned long paddr, 981 void __user *vaddr, 982 unsigned long dst_paddr, 983 void __user *dst_vaddr, 984 int size, int *error) 985 { 986 struct page *src_tpage = NULL; 987 struct page *dst_tpage = NULL; 988 int ret, len = size; 989 990 /* If source buffer is not aligned then use an intermediate buffer */ 991 if (!IS_ALIGNED((unsigned long)vaddr, 16)) { 992 src_tpage = alloc_page(GFP_KERNEL_ACCOUNT); 993 if (!src_tpage) 994 return -ENOMEM; 995 996 if (copy_from_user(page_address(src_tpage), vaddr, size)) { 997 __free_page(src_tpage); 998 return -EFAULT; 999 } 1000 1001 paddr = __sme_page_pa(src_tpage); 1002 } 1003 1004 /* 1005 * If destination buffer or length is not aligned then do read-modify-write: 1006 * - decrypt destination in an intermediate buffer 1007 * - copy the source buffer in an intermediate buffer 1008 * - use the intermediate buffer as source buffer 1009 */ 1010 if (!IS_ALIGNED((unsigned long)dst_vaddr, 16) || !IS_ALIGNED(size, 16)) { 1011 int dst_offset; 1012 1013 dst_tpage = alloc_page(GFP_KERNEL_ACCOUNT); 1014 if (!dst_tpage) { 1015 ret = -ENOMEM; 1016 goto e_free; 1017 } 1018 1019 ret = __sev_dbg_decrypt(kvm, dst_paddr, 1020 __sme_page_pa(dst_tpage), size, error); 1021 if (ret) 1022 goto e_free; 1023 1024 /* 1025 * If source is kernel buffer then use memcpy() otherwise 1026 * copy_from_user(). 1027 */ 1028 dst_offset = dst_paddr & 15; 1029 1030 if (src_tpage) 1031 memcpy(page_address(dst_tpage) + dst_offset, 1032 page_address(src_tpage), size); 1033 else { 1034 if (copy_from_user(page_address(dst_tpage) + dst_offset, 1035 vaddr, size)) { 1036 ret = -EFAULT; 1037 goto e_free; 1038 } 1039 } 1040 1041 paddr = __sme_page_pa(dst_tpage); 1042 dst_paddr = round_down(dst_paddr, 16); 1043 len = round_up(size, 16); 1044 } 1045 1046 ret = __sev_issue_dbg_cmd(kvm, paddr, dst_paddr, len, error, true); 1047 1048 e_free: 1049 if (src_tpage) 1050 __free_page(src_tpage); 1051 if (dst_tpage) 1052 __free_page(dst_tpage); 1053 return ret; 1054 } 1055 1056 static int sev_dbg_crypt(struct kvm *kvm, struct kvm_sev_cmd *argp, bool dec) 1057 { 1058 unsigned long vaddr, vaddr_end, next_vaddr; 1059 unsigned long dst_vaddr; 1060 struct page **src_p, **dst_p; 1061 struct kvm_sev_dbg debug; 1062 unsigned long n; 1063 unsigned int size; 1064 int ret; 1065 1066 if (!sev_guest(kvm)) 1067 return -ENOTTY; 1068 1069 if (copy_from_user(&debug, u64_to_user_ptr(argp->data), sizeof(debug))) 1070 return -EFAULT; 1071 1072 if (!debug.len || debug.src_uaddr + debug.len < debug.src_uaddr) 1073 return -EINVAL; 1074 if (!debug.dst_uaddr) 1075 return -EINVAL; 1076 1077 vaddr = debug.src_uaddr; 1078 size = debug.len; 1079 vaddr_end = vaddr + size; 1080 dst_vaddr = debug.dst_uaddr; 1081 1082 for (; vaddr < vaddr_end; vaddr = next_vaddr) { 1083 int len, s_off, d_off; 1084 1085 /* lock userspace source and destination page */ 1086 src_p = sev_pin_memory(kvm, vaddr & PAGE_MASK, PAGE_SIZE, &n, 0); 1087 if (IS_ERR(src_p)) 1088 return PTR_ERR(src_p); 1089 1090 dst_p = sev_pin_memory(kvm, dst_vaddr & PAGE_MASK, PAGE_SIZE, &n, 1); 1091 if (IS_ERR(dst_p)) { 1092 sev_unpin_memory(kvm, src_p, n); 1093 return PTR_ERR(dst_p); 1094 } 1095 1096 /* 1097 * Flush (on non-coherent CPUs) before DBG_{DE,EN}CRYPT read or modify 1098 * the pages; flush the destination too so that future accesses do not 1099 * see stale data. 1100 */ 1101 sev_clflush_pages(src_p, 1); 1102 sev_clflush_pages(dst_p, 1); 1103 1104 /* 1105 * Since user buffer may not be page aligned, calculate the 1106 * offset within the page. 1107 */ 1108 s_off = vaddr & ~PAGE_MASK; 1109 d_off = dst_vaddr & ~PAGE_MASK; 1110 len = min_t(size_t, (PAGE_SIZE - s_off), size); 1111 1112 if (dec) 1113 ret = __sev_dbg_decrypt_user(kvm, 1114 __sme_page_pa(src_p[0]) + s_off, 1115 (void __user *)dst_vaddr, 1116 __sme_page_pa(dst_p[0]) + d_off, 1117 len, &argp->error); 1118 else 1119 ret = __sev_dbg_encrypt_user(kvm, 1120 __sme_page_pa(src_p[0]) + s_off, 1121 (void __user *)vaddr, 1122 __sme_page_pa(dst_p[0]) + d_off, 1123 (void __user *)dst_vaddr, 1124 len, &argp->error); 1125 1126 sev_unpin_memory(kvm, src_p, n); 1127 sev_unpin_memory(kvm, dst_p, n); 1128 1129 if (ret) 1130 goto err; 1131 1132 next_vaddr = vaddr + len; 1133 dst_vaddr = dst_vaddr + len; 1134 size -= len; 1135 } 1136 err: 1137 return ret; 1138 } 1139 1140 static int sev_launch_secret(struct kvm *kvm, struct kvm_sev_cmd *argp) 1141 { 1142 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 1143 struct sev_data_launch_secret data; 1144 struct kvm_sev_launch_secret params; 1145 struct page **pages; 1146 void *blob, *hdr; 1147 unsigned long n, i; 1148 int ret, offset; 1149 1150 if (!sev_guest(kvm)) 1151 return -ENOTTY; 1152 1153 if (copy_from_user(¶ms, u64_to_user_ptr(argp->data), sizeof(params))) 1154 return -EFAULT; 1155 1156 pages = sev_pin_memory(kvm, params.guest_uaddr, params.guest_len, &n, 1); 1157 if (IS_ERR(pages)) 1158 return PTR_ERR(pages); 1159 1160 /* 1161 * Flush (on non-coherent CPUs) before LAUNCH_SECRET encrypts pages in 1162 * place; the cache may contain the data that was written unencrypted. 1163 */ 1164 sev_clflush_pages(pages, n); 1165 1166 /* 1167 * The secret must be copied into contiguous memory region, lets verify 1168 * that userspace memory pages are contiguous before we issue command. 1169 */ 1170 if (get_num_contig_pages(0, pages, n) != n) { 1171 ret = -EINVAL; 1172 goto e_unpin_memory; 1173 } 1174 1175 memset(&data, 0, sizeof(data)); 1176 1177 offset = params.guest_uaddr & (PAGE_SIZE - 1); 1178 data.guest_address = __sme_page_pa(pages[0]) + offset; 1179 data.guest_len = params.guest_len; 1180 1181 blob = psp_copy_user_blob(params.trans_uaddr, params.trans_len); 1182 if (IS_ERR(blob)) { 1183 ret = PTR_ERR(blob); 1184 goto e_unpin_memory; 1185 } 1186 1187 data.trans_address = __psp_pa(blob); 1188 data.trans_len = params.trans_len; 1189 1190 hdr = psp_copy_user_blob(params.hdr_uaddr, params.hdr_len); 1191 if (IS_ERR(hdr)) { 1192 ret = PTR_ERR(hdr); 1193 goto e_free_blob; 1194 } 1195 data.hdr_address = __psp_pa(hdr); 1196 data.hdr_len = params.hdr_len; 1197 1198 data.handle = sev->handle; 1199 ret = sev_issue_cmd(kvm, SEV_CMD_LAUNCH_UPDATE_SECRET, &data, &argp->error); 1200 1201 kfree(hdr); 1202 1203 e_free_blob: 1204 kfree(blob); 1205 e_unpin_memory: 1206 /* content of memory is updated, mark pages dirty */ 1207 for (i = 0; i < n; i++) { 1208 set_page_dirty_lock(pages[i]); 1209 mark_page_accessed(pages[i]); 1210 } 1211 sev_unpin_memory(kvm, pages, n); 1212 return ret; 1213 } 1214 1215 static int sev_get_attestation_report(struct kvm *kvm, struct kvm_sev_cmd *argp) 1216 { 1217 void __user *report = u64_to_user_ptr(argp->data); 1218 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 1219 struct sev_data_attestation_report data; 1220 struct kvm_sev_attestation_report params; 1221 void __user *p; 1222 void *blob = NULL; 1223 int ret; 1224 1225 if (!sev_guest(kvm)) 1226 return -ENOTTY; 1227 1228 if (copy_from_user(¶ms, u64_to_user_ptr(argp->data), sizeof(params))) 1229 return -EFAULT; 1230 1231 memset(&data, 0, sizeof(data)); 1232 1233 /* User wants to query the blob length */ 1234 if (!params.len) 1235 goto cmd; 1236 1237 p = u64_to_user_ptr(params.uaddr); 1238 if (p) { 1239 if (params.len > SEV_FW_BLOB_MAX_SIZE) 1240 return -EINVAL; 1241 1242 blob = kzalloc(params.len, GFP_KERNEL_ACCOUNT); 1243 if (!blob) 1244 return -ENOMEM; 1245 1246 data.address = __psp_pa(blob); 1247 data.len = params.len; 1248 memcpy(data.mnonce, params.mnonce, sizeof(params.mnonce)); 1249 } 1250 cmd: 1251 data.handle = sev->handle; 1252 ret = sev_issue_cmd(kvm, SEV_CMD_ATTESTATION_REPORT, &data, &argp->error); 1253 /* 1254 * If we query the session length, FW responded with expected data. 1255 */ 1256 if (!params.len) 1257 goto done; 1258 1259 if (ret) 1260 goto e_free_blob; 1261 1262 if (blob) { 1263 if (copy_to_user(p, blob, params.len)) 1264 ret = -EFAULT; 1265 } 1266 1267 done: 1268 params.len = data.len; 1269 if (copy_to_user(report, ¶ms, sizeof(params))) 1270 ret = -EFAULT; 1271 e_free_blob: 1272 kfree(blob); 1273 return ret; 1274 } 1275 1276 /* Userspace wants to query session length. */ 1277 static int 1278 __sev_send_start_query_session_length(struct kvm *kvm, struct kvm_sev_cmd *argp, 1279 struct kvm_sev_send_start *params) 1280 { 1281 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 1282 struct sev_data_send_start data; 1283 int ret; 1284 1285 memset(&data, 0, sizeof(data)); 1286 data.handle = sev->handle; 1287 ret = sev_issue_cmd(kvm, SEV_CMD_SEND_START, &data, &argp->error); 1288 1289 params->session_len = data.session_len; 1290 if (copy_to_user(u64_to_user_ptr(argp->data), params, 1291 sizeof(struct kvm_sev_send_start))) 1292 ret = -EFAULT; 1293 1294 return ret; 1295 } 1296 1297 static int sev_send_start(struct kvm *kvm, struct kvm_sev_cmd *argp) 1298 { 1299 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 1300 struct sev_data_send_start data; 1301 struct kvm_sev_send_start params; 1302 void *amd_certs, *session_data; 1303 void *pdh_cert, *plat_certs; 1304 int ret; 1305 1306 if (!sev_guest(kvm)) 1307 return -ENOTTY; 1308 1309 if (copy_from_user(¶ms, u64_to_user_ptr(argp->data), 1310 sizeof(struct kvm_sev_send_start))) 1311 return -EFAULT; 1312 1313 /* if session_len is zero, userspace wants to query the session length */ 1314 if (!params.session_len) 1315 return __sev_send_start_query_session_length(kvm, argp, 1316 ¶ms); 1317 1318 /* some sanity checks */ 1319 if (!params.pdh_cert_uaddr || !params.pdh_cert_len || 1320 !params.session_uaddr || params.session_len > SEV_FW_BLOB_MAX_SIZE) 1321 return -EINVAL; 1322 1323 /* allocate the memory to hold the session data blob */ 1324 session_data = kzalloc(params.session_len, GFP_KERNEL_ACCOUNT); 1325 if (!session_data) 1326 return -ENOMEM; 1327 1328 /* copy the certificate blobs from userspace */ 1329 pdh_cert = psp_copy_user_blob(params.pdh_cert_uaddr, 1330 params.pdh_cert_len); 1331 if (IS_ERR(pdh_cert)) { 1332 ret = PTR_ERR(pdh_cert); 1333 goto e_free_session; 1334 } 1335 1336 plat_certs = psp_copy_user_blob(params.plat_certs_uaddr, 1337 params.plat_certs_len); 1338 if (IS_ERR(plat_certs)) { 1339 ret = PTR_ERR(plat_certs); 1340 goto e_free_pdh; 1341 } 1342 1343 amd_certs = psp_copy_user_blob(params.amd_certs_uaddr, 1344 params.amd_certs_len); 1345 if (IS_ERR(amd_certs)) { 1346 ret = PTR_ERR(amd_certs); 1347 goto e_free_plat_cert; 1348 } 1349 1350 /* populate the FW SEND_START field with system physical address */ 1351 memset(&data, 0, sizeof(data)); 1352 data.pdh_cert_address = __psp_pa(pdh_cert); 1353 data.pdh_cert_len = params.pdh_cert_len; 1354 data.plat_certs_address = __psp_pa(plat_certs); 1355 data.plat_certs_len = params.plat_certs_len; 1356 data.amd_certs_address = __psp_pa(amd_certs); 1357 data.amd_certs_len = params.amd_certs_len; 1358 data.session_address = __psp_pa(session_data); 1359 data.session_len = params.session_len; 1360 data.handle = sev->handle; 1361 1362 ret = sev_issue_cmd(kvm, SEV_CMD_SEND_START, &data, &argp->error); 1363 1364 if (!ret && copy_to_user(u64_to_user_ptr(params.session_uaddr), 1365 session_data, params.session_len)) { 1366 ret = -EFAULT; 1367 goto e_free_amd_cert; 1368 } 1369 1370 params.policy = data.policy; 1371 params.session_len = data.session_len; 1372 if (copy_to_user(u64_to_user_ptr(argp->data), ¶ms, 1373 sizeof(struct kvm_sev_send_start))) 1374 ret = -EFAULT; 1375 1376 e_free_amd_cert: 1377 kfree(amd_certs); 1378 e_free_plat_cert: 1379 kfree(plat_certs); 1380 e_free_pdh: 1381 kfree(pdh_cert); 1382 e_free_session: 1383 kfree(session_data); 1384 return ret; 1385 } 1386 1387 /* Userspace wants to query either header or trans length. */ 1388 static int 1389 __sev_send_update_data_query_lengths(struct kvm *kvm, struct kvm_sev_cmd *argp, 1390 struct kvm_sev_send_update_data *params) 1391 { 1392 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 1393 struct sev_data_send_update_data data; 1394 int ret; 1395 1396 memset(&data, 0, sizeof(data)); 1397 data.handle = sev->handle; 1398 ret = sev_issue_cmd(kvm, SEV_CMD_SEND_UPDATE_DATA, &data, &argp->error); 1399 1400 params->hdr_len = data.hdr_len; 1401 params->trans_len = data.trans_len; 1402 1403 if (copy_to_user(u64_to_user_ptr(argp->data), params, 1404 sizeof(struct kvm_sev_send_update_data))) 1405 ret = -EFAULT; 1406 1407 return ret; 1408 } 1409 1410 static int sev_send_update_data(struct kvm *kvm, struct kvm_sev_cmd *argp) 1411 { 1412 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 1413 struct sev_data_send_update_data data; 1414 struct kvm_sev_send_update_data params; 1415 void *hdr, *trans_data; 1416 struct page **guest_page; 1417 unsigned long n; 1418 int ret, offset; 1419 1420 if (!sev_guest(kvm)) 1421 return -ENOTTY; 1422 1423 if (copy_from_user(¶ms, u64_to_user_ptr(argp->data), 1424 sizeof(struct kvm_sev_send_update_data))) 1425 return -EFAULT; 1426 1427 /* userspace wants to query either header or trans length */ 1428 if (!params.trans_len || !params.hdr_len) 1429 return __sev_send_update_data_query_lengths(kvm, argp, ¶ms); 1430 1431 if (!params.trans_uaddr || !params.guest_uaddr || 1432 !params.guest_len || !params.hdr_uaddr) 1433 return -EINVAL; 1434 1435 /* Check if we are crossing the page boundary */ 1436 offset = params.guest_uaddr & (PAGE_SIZE - 1); 1437 if (params.guest_len > PAGE_SIZE || (params.guest_len + offset) > PAGE_SIZE) 1438 return -EINVAL; 1439 1440 /* Pin guest memory */ 1441 guest_page = sev_pin_memory(kvm, params.guest_uaddr & PAGE_MASK, 1442 PAGE_SIZE, &n, 0); 1443 if (IS_ERR(guest_page)) 1444 return PTR_ERR(guest_page); 1445 1446 /* allocate memory for header and transport buffer */ 1447 ret = -ENOMEM; 1448 hdr = kzalloc(params.hdr_len, GFP_KERNEL_ACCOUNT); 1449 if (!hdr) 1450 goto e_unpin; 1451 1452 trans_data = kzalloc(params.trans_len, GFP_KERNEL_ACCOUNT); 1453 if (!trans_data) 1454 goto e_free_hdr; 1455 1456 memset(&data, 0, sizeof(data)); 1457 data.hdr_address = __psp_pa(hdr); 1458 data.hdr_len = params.hdr_len; 1459 data.trans_address = __psp_pa(trans_data); 1460 data.trans_len = params.trans_len; 1461 1462 /* The SEND_UPDATE_DATA command requires C-bit to be always set. */ 1463 data.guest_address = (page_to_pfn(guest_page[0]) << PAGE_SHIFT) + offset; 1464 data.guest_address |= sev_me_mask; 1465 data.guest_len = params.guest_len; 1466 data.handle = sev->handle; 1467 1468 ret = sev_issue_cmd(kvm, SEV_CMD_SEND_UPDATE_DATA, &data, &argp->error); 1469 1470 if (ret) 1471 goto e_free_trans_data; 1472 1473 /* copy transport buffer to user space */ 1474 if (copy_to_user(u64_to_user_ptr(params.trans_uaddr), 1475 trans_data, params.trans_len)) { 1476 ret = -EFAULT; 1477 goto e_free_trans_data; 1478 } 1479 1480 /* Copy packet header to userspace. */ 1481 if (copy_to_user(u64_to_user_ptr(params.hdr_uaddr), hdr, 1482 params.hdr_len)) 1483 ret = -EFAULT; 1484 1485 e_free_trans_data: 1486 kfree(trans_data); 1487 e_free_hdr: 1488 kfree(hdr); 1489 e_unpin: 1490 sev_unpin_memory(kvm, guest_page, n); 1491 1492 return ret; 1493 } 1494 1495 static int sev_send_finish(struct kvm *kvm, struct kvm_sev_cmd *argp) 1496 { 1497 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 1498 struct sev_data_send_finish data; 1499 1500 if (!sev_guest(kvm)) 1501 return -ENOTTY; 1502 1503 data.handle = sev->handle; 1504 return sev_issue_cmd(kvm, SEV_CMD_SEND_FINISH, &data, &argp->error); 1505 } 1506 1507 static int sev_send_cancel(struct kvm *kvm, struct kvm_sev_cmd *argp) 1508 { 1509 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 1510 struct sev_data_send_cancel data; 1511 1512 if (!sev_guest(kvm)) 1513 return -ENOTTY; 1514 1515 data.handle = sev->handle; 1516 return sev_issue_cmd(kvm, SEV_CMD_SEND_CANCEL, &data, &argp->error); 1517 } 1518 1519 static int sev_receive_start(struct kvm *kvm, struct kvm_sev_cmd *argp) 1520 { 1521 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 1522 struct sev_data_receive_start start; 1523 struct kvm_sev_receive_start params; 1524 int *error = &argp->error; 1525 void *session_data; 1526 void *pdh_data; 1527 int ret; 1528 1529 if (!sev_guest(kvm)) 1530 return -ENOTTY; 1531 1532 /* Get parameter from the userspace */ 1533 if (copy_from_user(¶ms, u64_to_user_ptr(argp->data), 1534 sizeof(struct kvm_sev_receive_start))) 1535 return -EFAULT; 1536 1537 /* some sanity checks */ 1538 if (!params.pdh_uaddr || !params.pdh_len || 1539 !params.session_uaddr || !params.session_len) 1540 return -EINVAL; 1541 1542 pdh_data = psp_copy_user_blob(params.pdh_uaddr, params.pdh_len); 1543 if (IS_ERR(pdh_data)) 1544 return PTR_ERR(pdh_data); 1545 1546 session_data = psp_copy_user_blob(params.session_uaddr, 1547 params.session_len); 1548 if (IS_ERR(session_data)) { 1549 ret = PTR_ERR(session_data); 1550 goto e_free_pdh; 1551 } 1552 1553 memset(&start, 0, sizeof(start)); 1554 start.handle = params.handle; 1555 start.policy = params.policy; 1556 start.pdh_cert_address = __psp_pa(pdh_data); 1557 start.pdh_cert_len = params.pdh_len; 1558 start.session_address = __psp_pa(session_data); 1559 start.session_len = params.session_len; 1560 1561 /* create memory encryption context */ 1562 ret = __sev_issue_cmd(argp->sev_fd, SEV_CMD_RECEIVE_START, &start, 1563 error); 1564 if (ret) 1565 goto e_free_session; 1566 1567 /* Bind ASID to this guest */ 1568 ret = sev_bind_asid(kvm, start.handle, error); 1569 if (ret) { 1570 sev_decommission(start.handle); 1571 goto e_free_session; 1572 } 1573 1574 params.handle = start.handle; 1575 if (copy_to_user(u64_to_user_ptr(argp->data), 1576 ¶ms, sizeof(struct kvm_sev_receive_start))) { 1577 ret = -EFAULT; 1578 sev_unbind_asid(kvm, start.handle); 1579 goto e_free_session; 1580 } 1581 1582 sev->handle = start.handle; 1583 sev->fd = argp->sev_fd; 1584 1585 e_free_session: 1586 kfree(session_data); 1587 e_free_pdh: 1588 kfree(pdh_data); 1589 1590 return ret; 1591 } 1592 1593 static int sev_receive_update_data(struct kvm *kvm, struct kvm_sev_cmd *argp) 1594 { 1595 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 1596 struct kvm_sev_receive_update_data params; 1597 struct sev_data_receive_update_data data; 1598 void *hdr = NULL, *trans = NULL; 1599 struct page **guest_page; 1600 unsigned long n; 1601 int ret, offset; 1602 1603 if (!sev_guest(kvm)) 1604 return -EINVAL; 1605 1606 if (copy_from_user(¶ms, u64_to_user_ptr(argp->data), 1607 sizeof(struct kvm_sev_receive_update_data))) 1608 return -EFAULT; 1609 1610 if (!params.hdr_uaddr || !params.hdr_len || 1611 !params.guest_uaddr || !params.guest_len || 1612 !params.trans_uaddr || !params.trans_len) 1613 return -EINVAL; 1614 1615 /* Check if we are crossing the page boundary */ 1616 offset = params.guest_uaddr & (PAGE_SIZE - 1); 1617 if (params.guest_len > PAGE_SIZE || (params.guest_len + offset) > PAGE_SIZE) 1618 return -EINVAL; 1619 1620 hdr = psp_copy_user_blob(params.hdr_uaddr, params.hdr_len); 1621 if (IS_ERR(hdr)) 1622 return PTR_ERR(hdr); 1623 1624 trans = psp_copy_user_blob(params.trans_uaddr, params.trans_len); 1625 if (IS_ERR(trans)) { 1626 ret = PTR_ERR(trans); 1627 goto e_free_hdr; 1628 } 1629 1630 memset(&data, 0, sizeof(data)); 1631 data.hdr_address = __psp_pa(hdr); 1632 data.hdr_len = params.hdr_len; 1633 data.trans_address = __psp_pa(trans); 1634 data.trans_len = params.trans_len; 1635 1636 /* Pin guest memory */ 1637 guest_page = sev_pin_memory(kvm, params.guest_uaddr & PAGE_MASK, 1638 PAGE_SIZE, &n, 1); 1639 if (IS_ERR(guest_page)) { 1640 ret = PTR_ERR(guest_page); 1641 goto e_free_trans; 1642 } 1643 1644 /* 1645 * Flush (on non-coherent CPUs) before RECEIVE_UPDATE_DATA, the PSP 1646 * encrypts the written data with the guest's key, and the cache may 1647 * contain dirty, unencrypted data. 1648 */ 1649 sev_clflush_pages(guest_page, n); 1650 1651 /* The RECEIVE_UPDATE_DATA command requires C-bit to be always set. */ 1652 data.guest_address = (page_to_pfn(guest_page[0]) << PAGE_SHIFT) + offset; 1653 data.guest_address |= sev_me_mask; 1654 data.guest_len = params.guest_len; 1655 data.handle = sev->handle; 1656 1657 ret = sev_issue_cmd(kvm, SEV_CMD_RECEIVE_UPDATE_DATA, &data, 1658 &argp->error); 1659 1660 sev_unpin_memory(kvm, guest_page, n); 1661 1662 e_free_trans: 1663 kfree(trans); 1664 e_free_hdr: 1665 kfree(hdr); 1666 1667 return ret; 1668 } 1669 1670 static int sev_receive_finish(struct kvm *kvm, struct kvm_sev_cmd *argp) 1671 { 1672 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 1673 struct sev_data_receive_finish data; 1674 1675 if (!sev_guest(kvm)) 1676 return -ENOTTY; 1677 1678 data.handle = sev->handle; 1679 return sev_issue_cmd(kvm, SEV_CMD_RECEIVE_FINISH, &data, &argp->error); 1680 } 1681 1682 static bool is_cmd_allowed_from_mirror(u32 cmd_id) 1683 { 1684 /* 1685 * Allow mirrors VM to call KVM_SEV_LAUNCH_UPDATE_VMSA to enable SEV-ES 1686 * active mirror VMs. Also allow the debugging and status commands. 1687 */ 1688 if (cmd_id == KVM_SEV_LAUNCH_UPDATE_VMSA || 1689 cmd_id == KVM_SEV_GUEST_STATUS || cmd_id == KVM_SEV_DBG_DECRYPT || 1690 cmd_id == KVM_SEV_DBG_ENCRYPT) 1691 return true; 1692 1693 return false; 1694 } 1695 1696 static int sev_lock_two_vms(struct kvm *dst_kvm, struct kvm *src_kvm) 1697 { 1698 struct kvm_sev_info *dst_sev = &to_kvm_svm(dst_kvm)->sev_info; 1699 struct kvm_sev_info *src_sev = &to_kvm_svm(src_kvm)->sev_info; 1700 int r = -EBUSY; 1701 1702 if (dst_kvm == src_kvm) 1703 return -EINVAL; 1704 1705 /* 1706 * Bail if these VMs are already involved in a migration to avoid 1707 * deadlock between two VMs trying to migrate to/from each other. 1708 */ 1709 if (atomic_cmpxchg_acquire(&dst_sev->migration_in_progress, 0, 1)) 1710 return -EBUSY; 1711 1712 if (atomic_cmpxchg_acquire(&src_sev->migration_in_progress, 0, 1)) 1713 goto release_dst; 1714 1715 r = -EINTR; 1716 if (mutex_lock_killable(&dst_kvm->lock)) 1717 goto release_src; 1718 if (mutex_lock_killable_nested(&src_kvm->lock, SINGLE_DEPTH_NESTING)) 1719 goto unlock_dst; 1720 return 0; 1721 1722 unlock_dst: 1723 mutex_unlock(&dst_kvm->lock); 1724 release_src: 1725 atomic_set_release(&src_sev->migration_in_progress, 0); 1726 release_dst: 1727 atomic_set_release(&dst_sev->migration_in_progress, 0); 1728 return r; 1729 } 1730 1731 static void sev_unlock_two_vms(struct kvm *dst_kvm, struct kvm *src_kvm) 1732 { 1733 struct kvm_sev_info *dst_sev = &to_kvm_svm(dst_kvm)->sev_info; 1734 struct kvm_sev_info *src_sev = &to_kvm_svm(src_kvm)->sev_info; 1735 1736 mutex_unlock(&dst_kvm->lock); 1737 mutex_unlock(&src_kvm->lock); 1738 atomic_set_release(&dst_sev->migration_in_progress, 0); 1739 atomic_set_release(&src_sev->migration_in_progress, 0); 1740 } 1741 1742 /* vCPU mutex subclasses. */ 1743 enum sev_migration_role { 1744 SEV_MIGRATION_SOURCE = 0, 1745 SEV_MIGRATION_TARGET, 1746 SEV_NR_MIGRATION_ROLES, 1747 }; 1748 1749 static int sev_lock_vcpus_for_migration(struct kvm *kvm, 1750 enum sev_migration_role role) 1751 { 1752 struct kvm_vcpu *vcpu; 1753 unsigned long i, j; 1754 1755 kvm_for_each_vcpu(i, vcpu, kvm) { 1756 if (mutex_lock_killable_nested(&vcpu->mutex, role)) 1757 goto out_unlock; 1758 1759 #ifdef CONFIG_PROVE_LOCKING 1760 if (!i) 1761 /* 1762 * Reset the role to one that avoids colliding with 1763 * the role used for the first vcpu mutex. 1764 */ 1765 role = SEV_NR_MIGRATION_ROLES; 1766 else 1767 mutex_release(&vcpu->mutex.dep_map, _THIS_IP_); 1768 #endif 1769 } 1770 1771 return 0; 1772 1773 out_unlock: 1774 1775 kvm_for_each_vcpu(j, vcpu, kvm) { 1776 if (i == j) 1777 break; 1778 1779 #ifdef CONFIG_PROVE_LOCKING 1780 if (j) 1781 mutex_acquire(&vcpu->mutex.dep_map, role, 0, _THIS_IP_); 1782 #endif 1783 1784 mutex_unlock(&vcpu->mutex); 1785 } 1786 return -EINTR; 1787 } 1788 1789 static void sev_unlock_vcpus_for_migration(struct kvm *kvm) 1790 { 1791 struct kvm_vcpu *vcpu; 1792 unsigned long i; 1793 bool first = true; 1794 1795 kvm_for_each_vcpu(i, vcpu, kvm) { 1796 if (first) 1797 first = false; 1798 else 1799 mutex_acquire(&vcpu->mutex.dep_map, 1800 SEV_NR_MIGRATION_ROLES, 0, _THIS_IP_); 1801 1802 mutex_unlock(&vcpu->mutex); 1803 } 1804 } 1805 1806 static void sev_migrate_from(struct kvm *dst_kvm, struct kvm *src_kvm) 1807 { 1808 struct kvm_sev_info *dst = &to_kvm_svm(dst_kvm)->sev_info; 1809 struct kvm_sev_info *src = &to_kvm_svm(src_kvm)->sev_info; 1810 struct kvm_vcpu *dst_vcpu, *src_vcpu; 1811 struct vcpu_svm *dst_svm, *src_svm; 1812 struct kvm_sev_info *mirror; 1813 unsigned long i; 1814 1815 dst->active = true; 1816 dst->asid = src->asid; 1817 dst->handle = src->handle; 1818 dst->pages_locked = src->pages_locked; 1819 dst->enc_context_owner = src->enc_context_owner; 1820 dst->es_active = src->es_active; 1821 dst->vmsa_features = src->vmsa_features; 1822 1823 src->asid = 0; 1824 src->active = false; 1825 src->handle = 0; 1826 src->pages_locked = 0; 1827 src->enc_context_owner = NULL; 1828 src->es_active = false; 1829 1830 list_cut_before(&dst->regions_list, &src->regions_list, &src->regions_list); 1831 1832 /* 1833 * If this VM has mirrors, "transfer" each mirror's refcount of the 1834 * source to the destination (this KVM). The caller holds a reference 1835 * to the source, so there's no danger of use-after-free. 1836 */ 1837 list_cut_before(&dst->mirror_vms, &src->mirror_vms, &src->mirror_vms); 1838 list_for_each_entry(mirror, &dst->mirror_vms, mirror_entry) { 1839 kvm_get_kvm(dst_kvm); 1840 kvm_put_kvm(src_kvm); 1841 mirror->enc_context_owner = dst_kvm; 1842 } 1843 1844 /* 1845 * If this VM is a mirror, remove the old mirror from the owners list 1846 * and add the new mirror to the list. 1847 */ 1848 if (is_mirroring_enc_context(dst_kvm)) { 1849 struct kvm_sev_info *owner_sev_info = 1850 &to_kvm_svm(dst->enc_context_owner)->sev_info; 1851 1852 list_del(&src->mirror_entry); 1853 list_add_tail(&dst->mirror_entry, &owner_sev_info->mirror_vms); 1854 } 1855 1856 kvm_for_each_vcpu(i, dst_vcpu, dst_kvm) { 1857 dst_svm = to_svm(dst_vcpu); 1858 1859 sev_init_vmcb(dst_svm); 1860 1861 if (!dst->es_active) 1862 continue; 1863 1864 /* 1865 * Note, the source is not required to have the same number of 1866 * vCPUs as the destination when migrating a vanilla SEV VM. 1867 */ 1868 src_vcpu = kvm_get_vcpu(src_kvm, i); 1869 src_svm = to_svm(src_vcpu); 1870 1871 /* 1872 * Transfer VMSA and GHCB state to the destination. Nullify and 1873 * clear source fields as appropriate, the state now belongs to 1874 * the destination. 1875 */ 1876 memcpy(&dst_svm->sev_es, &src_svm->sev_es, sizeof(src_svm->sev_es)); 1877 dst_svm->vmcb->control.ghcb_gpa = src_svm->vmcb->control.ghcb_gpa; 1878 dst_svm->vmcb->control.vmsa_pa = src_svm->vmcb->control.vmsa_pa; 1879 dst_vcpu->arch.guest_state_protected = true; 1880 1881 memset(&src_svm->sev_es, 0, sizeof(src_svm->sev_es)); 1882 src_svm->vmcb->control.ghcb_gpa = INVALID_PAGE; 1883 src_svm->vmcb->control.vmsa_pa = INVALID_PAGE; 1884 src_vcpu->arch.guest_state_protected = false; 1885 } 1886 } 1887 1888 static int sev_check_source_vcpus(struct kvm *dst, struct kvm *src) 1889 { 1890 struct kvm_vcpu *src_vcpu; 1891 unsigned long i; 1892 1893 if (!sev_es_guest(src)) 1894 return 0; 1895 1896 if (atomic_read(&src->online_vcpus) != atomic_read(&dst->online_vcpus)) 1897 return -EINVAL; 1898 1899 kvm_for_each_vcpu(i, src_vcpu, src) { 1900 if (!src_vcpu->arch.guest_state_protected) 1901 return -EINVAL; 1902 } 1903 1904 return 0; 1905 } 1906 1907 int sev_vm_move_enc_context_from(struct kvm *kvm, unsigned int source_fd) 1908 { 1909 struct kvm_sev_info *dst_sev = &to_kvm_svm(kvm)->sev_info; 1910 struct kvm_sev_info *src_sev, *cg_cleanup_sev; 1911 struct fd f = fdget(source_fd); 1912 struct kvm *source_kvm; 1913 bool charged = false; 1914 int ret; 1915 1916 if (!f.file) 1917 return -EBADF; 1918 1919 if (!file_is_kvm(f.file)) { 1920 ret = -EBADF; 1921 goto out_fput; 1922 } 1923 1924 source_kvm = f.file->private_data; 1925 ret = sev_lock_two_vms(kvm, source_kvm); 1926 if (ret) 1927 goto out_fput; 1928 1929 if (kvm->arch.vm_type != source_kvm->arch.vm_type || 1930 sev_guest(kvm) || !sev_guest(source_kvm)) { 1931 ret = -EINVAL; 1932 goto out_unlock; 1933 } 1934 1935 src_sev = &to_kvm_svm(source_kvm)->sev_info; 1936 1937 dst_sev->misc_cg = get_current_misc_cg(); 1938 cg_cleanup_sev = dst_sev; 1939 if (dst_sev->misc_cg != src_sev->misc_cg) { 1940 ret = sev_misc_cg_try_charge(dst_sev); 1941 if (ret) 1942 goto out_dst_cgroup; 1943 charged = true; 1944 } 1945 1946 ret = sev_lock_vcpus_for_migration(kvm, SEV_MIGRATION_SOURCE); 1947 if (ret) 1948 goto out_dst_cgroup; 1949 ret = sev_lock_vcpus_for_migration(source_kvm, SEV_MIGRATION_TARGET); 1950 if (ret) 1951 goto out_dst_vcpu; 1952 1953 ret = sev_check_source_vcpus(kvm, source_kvm); 1954 if (ret) 1955 goto out_source_vcpu; 1956 1957 sev_migrate_from(kvm, source_kvm); 1958 kvm_vm_dead(source_kvm); 1959 cg_cleanup_sev = src_sev; 1960 ret = 0; 1961 1962 out_source_vcpu: 1963 sev_unlock_vcpus_for_migration(source_kvm); 1964 out_dst_vcpu: 1965 sev_unlock_vcpus_for_migration(kvm); 1966 out_dst_cgroup: 1967 /* Operates on the source on success, on the destination on failure. */ 1968 if (charged) 1969 sev_misc_cg_uncharge(cg_cleanup_sev); 1970 put_misc_cg(cg_cleanup_sev->misc_cg); 1971 cg_cleanup_sev->misc_cg = NULL; 1972 out_unlock: 1973 sev_unlock_two_vms(kvm, source_kvm); 1974 out_fput: 1975 fdput(f); 1976 return ret; 1977 } 1978 1979 int sev_dev_get_attr(u32 group, u64 attr, u64 *val) 1980 { 1981 if (group != KVM_X86_GRP_SEV) 1982 return -ENXIO; 1983 1984 switch (attr) { 1985 case KVM_X86_SEV_VMSA_FEATURES: 1986 *val = sev_supported_vmsa_features; 1987 return 0; 1988 1989 default: 1990 return -ENXIO; 1991 } 1992 } 1993 1994 int sev_mem_enc_ioctl(struct kvm *kvm, void __user *argp) 1995 { 1996 struct kvm_sev_cmd sev_cmd; 1997 int r; 1998 1999 if (!sev_enabled) 2000 return -ENOTTY; 2001 2002 if (!argp) 2003 return 0; 2004 2005 if (copy_from_user(&sev_cmd, argp, sizeof(struct kvm_sev_cmd))) 2006 return -EFAULT; 2007 2008 mutex_lock(&kvm->lock); 2009 2010 /* Only the enc_context_owner handles some memory enc operations. */ 2011 if (is_mirroring_enc_context(kvm) && 2012 !is_cmd_allowed_from_mirror(sev_cmd.id)) { 2013 r = -EINVAL; 2014 goto out; 2015 } 2016 2017 switch (sev_cmd.id) { 2018 case KVM_SEV_ES_INIT: 2019 if (!sev_es_enabled) { 2020 r = -ENOTTY; 2021 goto out; 2022 } 2023 fallthrough; 2024 case KVM_SEV_INIT: 2025 r = sev_guest_init(kvm, &sev_cmd); 2026 break; 2027 case KVM_SEV_INIT2: 2028 r = sev_guest_init2(kvm, &sev_cmd); 2029 break; 2030 case KVM_SEV_LAUNCH_START: 2031 r = sev_launch_start(kvm, &sev_cmd); 2032 break; 2033 case KVM_SEV_LAUNCH_UPDATE_DATA: 2034 r = sev_launch_update_data(kvm, &sev_cmd); 2035 break; 2036 case KVM_SEV_LAUNCH_UPDATE_VMSA: 2037 r = sev_launch_update_vmsa(kvm, &sev_cmd); 2038 break; 2039 case KVM_SEV_LAUNCH_MEASURE: 2040 r = sev_launch_measure(kvm, &sev_cmd); 2041 break; 2042 case KVM_SEV_LAUNCH_FINISH: 2043 r = sev_launch_finish(kvm, &sev_cmd); 2044 break; 2045 case KVM_SEV_GUEST_STATUS: 2046 r = sev_guest_status(kvm, &sev_cmd); 2047 break; 2048 case KVM_SEV_DBG_DECRYPT: 2049 r = sev_dbg_crypt(kvm, &sev_cmd, true); 2050 break; 2051 case KVM_SEV_DBG_ENCRYPT: 2052 r = sev_dbg_crypt(kvm, &sev_cmd, false); 2053 break; 2054 case KVM_SEV_LAUNCH_SECRET: 2055 r = sev_launch_secret(kvm, &sev_cmd); 2056 break; 2057 case KVM_SEV_GET_ATTESTATION_REPORT: 2058 r = sev_get_attestation_report(kvm, &sev_cmd); 2059 break; 2060 case KVM_SEV_SEND_START: 2061 r = sev_send_start(kvm, &sev_cmd); 2062 break; 2063 case KVM_SEV_SEND_UPDATE_DATA: 2064 r = sev_send_update_data(kvm, &sev_cmd); 2065 break; 2066 case KVM_SEV_SEND_FINISH: 2067 r = sev_send_finish(kvm, &sev_cmd); 2068 break; 2069 case KVM_SEV_SEND_CANCEL: 2070 r = sev_send_cancel(kvm, &sev_cmd); 2071 break; 2072 case KVM_SEV_RECEIVE_START: 2073 r = sev_receive_start(kvm, &sev_cmd); 2074 break; 2075 case KVM_SEV_RECEIVE_UPDATE_DATA: 2076 r = sev_receive_update_data(kvm, &sev_cmd); 2077 break; 2078 case KVM_SEV_RECEIVE_FINISH: 2079 r = sev_receive_finish(kvm, &sev_cmd); 2080 break; 2081 default: 2082 r = -EINVAL; 2083 goto out; 2084 } 2085 2086 if (copy_to_user(argp, &sev_cmd, sizeof(struct kvm_sev_cmd))) 2087 r = -EFAULT; 2088 2089 out: 2090 mutex_unlock(&kvm->lock); 2091 return r; 2092 } 2093 2094 int sev_mem_enc_register_region(struct kvm *kvm, 2095 struct kvm_enc_region *range) 2096 { 2097 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 2098 struct enc_region *region; 2099 int ret = 0; 2100 2101 if (!sev_guest(kvm)) 2102 return -ENOTTY; 2103 2104 /* If kvm is mirroring encryption context it isn't responsible for it */ 2105 if (is_mirroring_enc_context(kvm)) 2106 return -EINVAL; 2107 2108 if (range->addr > ULONG_MAX || range->size > ULONG_MAX) 2109 return -EINVAL; 2110 2111 region = kzalloc(sizeof(*region), GFP_KERNEL_ACCOUNT); 2112 if (!region) 2113 return -ENOMEM; 2114 2115 mutex_lock(&kvm->lock); 2116 region->pages = sev_pin_memory(kvm, range->addr, range->size, ®ion->npages, 1); 2117 if (IS_ERR(region->pages)) { 2118 ret = PTR_ERR(region->pages); 2119 mutex_unlock(&kvm->lock); 2120 goto e_free; 2121 } 2122 2123 /* 2124 * The guest may change the memory encryption attribute from C=0 -> C=1 2125 * or vice versa for this memory range. Lets make sure caches are 2126 * flushed to ensure that guest data gets written into memory with 2127 * correct C-bit. Note, this must be done before dropping kvm->lock, 2128 * as region and its array of pages can be freed by a different task 2129 * once kvm->lock is released. 2130 */ 2131 sev_clflush_pages(region->pages, region->npages); 2132 2133 region->uaddr = range->addr; 2134 region->size = range->size; 2135 2136 list_add_tail(®ion->list, &sev->regions_list); 2137 mutex_unlock(&kvm->lock); 2138 2139 return ret; 2140 2141 e_free: 2142 kfree(region); 2143 return ret; 2144 } 2145 2146 static struct enc_region * 2147 find_enc_region(struct kvm *kvm, struct kvm_enc_region *range) 2148 { 2149 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 2150 struct list_head *head = &sev->regions_list; 2151 struct enc_region *i; 2152 2153 list_for_each_entry(i, head, list) { 2154 if (i->uaddr == range->addr && 2155 i->size == range->size) 2156 return i; 2157 } 2158 2159 return NULL; 2160 } 2161 2162 static void __unregister_enc_region_locked(struct kvm *kvm, 2163 struct enc_region *region) 2164 { 2165 sev_unpin_memory(kvm, region->pages, region->npages); 2166 list_del(®ion->list); 2167 kfree(region); 2168 } 2169 2170 int sev_mem_enc_unregister_region(struct kvm *kvm, 2171 struct kvm_enc_region *range) 2172 { 2173 struct enc_region *region; 2174 int ret; 2175 2176 /* If kvm is mirroring encryption context it isn't responsible for it */ 2177 if (is_mirroring_enc_context(kvm)) 2178 return -EINVAL; 2179 2180 mutex_lock(&kvm->lock); 2181 2182 if (!sev_guest(kvm)) { 2183 ret = -ENOTTY; 2184 goto failed; 2185 } 2186 2187 region = find_enc_region(kvm, range); 2188 if (!region) { 2189 ret = -EINVAL; 2190 goto failed; 2191 } 2192 2193 /* 2194 * Ensure that all guest tagged cache entries are flushed before 2195 * releasing the pages back to the system for use. CLFLUSH will 2196 * not do this, so issue a WBINVD. 2197 */ 2198 wbinvd_on_all_cpus(); 2199 2200 __unregister_enc_region_locked(kvm, region); 2201 2202 mutex_unlock(&kvm->lock); 2203 return 0; 2204 2205 failed: 2206 mutex_unlock(&kvm->lock); 2207 return ret; 2208 } 2209 2210 int sev_vm_copy_enc_context_from(struct kvm *kvm, unsigned int source_fd) 2211 { 2212 struct fd f = fdget(source_fd); 2213 struct kvm *source_kvm; 2214 struct kvm_sev_info *source_sev, *mirror_sev; 2215 int ret; 2216 2217 if (!f.file) 2218 return -EBADF; 2219 2220 if (!file_is_kvm(f.file)) { 2221 ret = -EBADF; 2222 goto e_source_fput; 2223 } 2224 2225 source_kvm = f.file->private_data; 2226 ret = sev_lock_two_vms(kvm, source_kvm); 2227 if (ret) 2228 goto e_source_fput; 2229 2230 /* 2231 * Mirrors of mirrors should work, but let's not get silly. Also 2232 * disallow out-of-band SEV/SEV-ES init if the target is already an 2233 * SEV guest, or if vCPUs have been created. KVM relies on vCPUs being 2234 * created after SEV/SEV-ES initialization, e.g. to init intercepts. 2235 */ 2236 if (sev_guest(kvm) || !sev_guest(source_kvm) || 2237 is_mirroring_enc_context(source_kvm) || kvm->created_vcpus) { 2238 ret = -EINVAL; 2239 goto e_unlock; 2240 } 2241 2242 /* 2243 * The mirror kvm holds an enc_context_owner ref so its asid can't 2244 * disappear until we're done with it 2245 */ 2246 source_sev = &to_kvm_svm(source_kvm)->sev_info; 2247 kvm_get_kvm(source_kvm); 2248 mirror_sev = &to_kvm_svm(kvm)->sev_info; 2249 list_add_tail(&mirror_sev->mirror_entry, &source_sev->mirror_vms); 2250 2251 /* Set enc_context_owner and copy its encryption context over */ 2252 mirror_sev->enc_context_owner = source_kvm; 2253 mirror_sev->active = true; 2254 mirror_sev->asid = source_sev->asid; 2255 mirror_sev->fd = source_sev->fd; 2256 mirror_sev->es_active = source_sev->es_active; 2257 mirror_sev->need_init = false; 2258 mirror_sev->handle = source_sev->handle; 2259 INIT_LIST_HEAD(&mirror_sev->regions_list); 2260 INIT_LIST_HEAD(&mirror_sev->mirror_vms); 2261 ret = 0; 2262 2263 /* 2264 * Do not copy ap_jump_table. Since the mirror does not share the same 2265 * KVM contexts as the original, and they may have different 2266 * memory-views. 2267 */ 2268 2269 e_unlock: 2270 sev_unlock_two_vms(kvm, source_kvm); 2271 e_source_fput: 2272 fdput(f); 2273 return ret; 2274 } 2275 2276 void sev_vm_destroy(struct kvm *kvm) 2277 { 2278 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 2279 struct list_head *head = &sev->regions_list; 2280 struct list_head *pos, *q; 2281 2282 if (!sev_guest(kvm)) 2283 return; 2284 2285 WARN_ON(!list_empty(&sev->mirror_vms)); 2286 2287 /* If this is a mirror_kvm release the enc_context_owner and skip sev cleanup */ 2288 if (is_mirroring_enc_context(kvm)) { 2289 struct kvm *owner_kvm = sev->enc_context_owner; 2290 2291 mutex_lock(&owner_kvm->lock); 2292 list_del(&sev->mirror_entry); 2293 mutex_unlock(&owner_kvm->lock); 2294 kvm_put_kvm(owner_kvm); 2295 return; 2296 } 2297 2298 /* 2299 * Ensure that all guest tagged cache entries are flushed before 2300 * releasing the pages back to the system for use. CLFLUSH will 2301 * not do this, so issue a WBINVD. 2302 */ 2303 wbinvd_on_all_cpus(); 2304 2305 /* 2306 * if userspace was terminated before unregistering the memory regions 2307 * then lets unpin all the registered memory. 2308 */ 2309 if (!list_empty(head)) { 2310 list_for_each_safe(pos, q, head) { 2311 __unregister_enc_region_locked(kvm, 2312 list_entry(pos, struct enc_region, list)); 2313 cond_resched(); 2314 } 2315 } 2316 2317 sev_unbind_asid(kvm, sev->handle); 2318 sev_asid_free(sev); 2319 } 2320 2321 void __init sev_set_cpu_caps(void) 2322 { 2323 if (sev_enabled) { 2324 kvm_cpu_cap_set(X86_FEATURE_SEV); 2325 kvm_caps.supported_vm_types |= BIT(KVM_X86_SEV_VM); 2326 } 2327 if (sev_es_enabled) { 2328 kvm_cpu_cap_set(X86_FEATURE_SEV_ES); 2329 kvm_caps.supported_vm_types |= BIT(KVM_X86_SEV_ES_VM); 2330 } 2331 } 2332 2333 void __init sev_hardware_setup(void) 2334 { 2335 unsigned int eax, ebx, ecx, edx, sev_asid_count, sev_es_asid_count; 2336 bool sev_es_supported = false; 2337 bool sev_supported = false; 2338 2339 if (!sev_enabled || !npt_enabled || !nrips) 2340 goto out; 2341 2342 /* 2343 * SEV must obviously be supported in hardware. Sanity check that the 2344 * CPU supports decode assists, which is mandatory for SEV guests to 2345 * support instruction emulation. Ditto for flushing by ASID, as SEV 2346 * guests are bound to a single ASID, i.e. KVM can't rotate to a new 2347 * ASID to effect a TLB flush. 2348 */ 2349 if (!boot_cpu_has(X86_FEATURE_SEV) || 2350 WARN_ON_ONCE(!boot_cpu_has(X86_FEATURE_DECODEASSISTS)) || 2351 WARN_ON_ONCE(!boot_cpu_has(X86_FEATURE_FLUSHBYASID))) 2352 goto out; 2353 2354 /* Retrieve SEV CPUID information */ 2355 cpuid(0x8000001f, &eax, &ebx, &ecx, &edx); 2356 2357 /* Set encryption bit location for SEV-ES guests */ 2358 sev_enc_bit = ebx & 0x3f; 2359 2360 /* Maximum number of encrypted guests supported simultaneously */ 2361 max_sev_asid = ecx; 2362 if (!max_sev_asid) 2363 goto out; 2364 2365 /* Minimum ASID value that should be used for SEV guest */ 2366 min_sev_asid = edx; 2367 sev_me_mask = 1UL << (ebx & 0x3f); 2368 2369 /* 2370 * Initialize SEV ASID bitmaps. Allocate space for ASID 0 in the bitmap, 2371 * even though it's never used, so that the bitmap is indexed by the 2372 * actual ASID. 2373 */ 2374 nr_asids = max_sev_asid + 1; 2375 sev_asid_bitmap = bitmap_zalloc(nr_asids, GFP_KERNEL); 2376 if (!sev_asid_bitmap) 2377 goto out; 2378 2379 sev_reclaim_asid_bitmap = bitmap_zalloc(nr_asids, GFP_KERNEL); 2380 if (!sev_reclaim_asid_bitmap) { 2381 bitmap_free(sev_asid_bitmap); 2382 sev_asid_bitmap = NULL; 2383 goto out; 2384 } 2385 2386 if (min_sev_asid <= max_sev_asid) { 2387 sev_asid_count = max_sev_asid - min_sev_asid + 1; 2388 WARN_ON_ONCE(misc_cg_set_capacity(MISC_CG_RES_SEV, sev_asid_count)); 2389 } 2390 sev_supported = true; 2391 2392 /* SEV-ES support requested? */ 2393 if (!sev_es_enabled) 2394 goto out; 2395 2396 /* 2397 * SEV-ES requires MMIO caching as KVM doesn't have access to the guest 2398 * instruction stream, i.e. can't emulate in response to a #NPF and 2399 * instead relies on #NPF(RSVD) being reflected into the guest as #VC 2400 * (the guest can then do a #VMGEXIT to request MMIO emulation). 2401 */ 2402 if (!enable_mmio_caching) 2403 goto out; 2404 2405 /* Does the CPU support SEV-ES? */ 2406 if (!boot_cpu_has(X86_FEATURE_SEV_ES)) 2407 goto out; 2408 2409 /* Has the system been allocated ASIDs for SEV-ES? */ 2410 if (min_sev_asid == 1) 2411 goto out; 2412 2413 sev_es_asid_count = min_sev_asid - 1; 2414 WARN_ON_ONCE(misc_cg_set_capacity(MISC_CG_RES_SEV_ES, sev_es_asid_count)); 2415 sev_es_supported = true; 2416 2417 out: 2418 if (boot_cpu_has(X86_FEATURE_SEV)) 2419 pr_info("SEV %s (ASIDs %u - %u)\n", 2420 sev_supported ? min_sev_asid <= max_sev_asid ? "enabled" : 2421 "unusable" : 2422 "disabled", 2423 min_sev_asid, max_sev_asid); 2424 if (boot_cpu_has(X86_FEATURE_SEV_ES)) 2425 pr_info("SEV-ES %s (ASIDs %u - %u)\n", 2426 sev_es_supported ? "enabled" : "disabled", 2427 min_sev_asid > 1 ? 1 : 0, min_sev_asid - 1); 2428 2429 sev_enabled = sev_supported; 2430 sev_es_enabled = sev_es_supported; 2431 if (!sev_es_enabled || !cpu_feature_enabled(X86_FEATURE_DEBUG_SWAP) || 2432 !cpu_feature_enabled(X86_FEATURE_NO_NESTED_DATA_BP)) 2433 sev_es_debug_swap_enabled = false; 2434 2435 sev_supported_vmsa_features = 0; 2436 if (sev_es_debug_swap_enabled) 2437 sev_supported_vmsa_features |= SVM_SEV_FEAT_DEBUG_SWAP; 2438 } 2439 2440 void sev_hardware_unsetup(void) 2441 { 2442 if (!sev_enabled) 2443 return; 2444 2445 /* No need to take sev_bitmap_lock, all VMs have been destroyed. */ 2446 sev_flush_asids(1, max_sev_asid); 2447 2448 bitmap_free(sev_asid_bitmap); 2449 bitmap_free(sev_reclaim_asid_bitmap); 2450 2451 misc_cg_set_capacity(MISC_CG_RES_SEV, 0); 2452 misc_cg_set_capacity(MISC_CG_RES_SEV_ES, 0); 2453 } 2454 2455 int sev_cpu_init(struct svm_cpu_data *sd) 2456 { 2457 if (!sev_enabled) 2458 return 0; 2459 2460 sd->sev_vmcbs = kcalloc(nr_asids, sizeof(void *), GFP_KERNEL); 2461 if (!sd->sev_vmcbs) 2462 return -ENOMEM; 2463 2464 return 0; 2465 } 2466 2467 /* 2468 * Pages used by hardware to hold guest encrypted state must be flushed before 2469 * returning them to the system. 2470 */ 2471 static void sev_flush_encrypted_page(struct kvm_vcpu *vcpu, void *va) 2472 { 2473 unsigned int asid = sev_get_asid(vcpu->kvm); 2474 2475 /* 2476 * Note! The address must be a kernel address, as regular page walk 2477 * checks are performed by VM_PAGE_FLUSH, i.e. operating on a user 2478 * address is non-deterministic and unsafe. This function deliberately 2479 * takes a pointer to deter passing in a user address. 2480 */ 2481 unsigned long addr = (unsigned long)va; 2482 2483 /* 2484 * If CPU enforced cache coherency for encrypted mappings of the 2485 * same physical page is supported, use CLFLUSHOPT instead. NOTE: cache 2486 * flush is still needed in order to work properly with DMA devices. 2487 */ 2488 if (boot_cpu_has(X86_FEATURE_SME_COHERENT)) { 2489 clflush_cache_range(va, PAGE_SIZE); 2490 return; 2491 } 2492 2493 /* 2494 * VM Page Flush takes a host virtual address and a guest ASID. Fall 2495 * back to WBINVD if this faults so as not to make any problems worse 2496 * by leaving stale encrypted data in the cache. 2497 */ 2498 if (WARN_ON_ONCE(wrmsrl_safe(MSR_AMD64_VM_PAGE_FLUSH, addr | asid))) 2499 goto do_wbinvd; 2500 2501 return; 2502 2503 do_wbinvd: 2504 wbinvd_on_all_cpus(); 2505 } 2506 2507 void sev_guest_memory_reclaimed(struct kvm *kvm) 2508 { 2509 if (!sev_guest(kvm)) 2510 return; 2511 2512 wbinvd_on_all_cpus(); 2513 } 2514 2515 void sev_free_vcpu(struct kvm_vcpu *vcpu) 2516 { 2517 struct vcpu_svm *svm; 2518 2519 if (!sev_es_guest(vcpu->kvm)) 2520 return; 2521 2522 svm = to_svm(vcpu); 2523 2524 if (vcpu->arch.guest_state_protected) 2525 sev_flush_encrypted_page(vcpu, svm->sev_es.vmsa); 2526 2527 __free_page(virt_to_page(svm->sev_es.vmsa)); 2528 2529 if (svm->sev_es.ghcb_sa_free) 2530 kvfree(svm->sev_es.ghcb_sa); 2531 } 2532 2533 static void dump_ghcb(struct vcpu_svm *svm) 2534 { 2535 struct ghcb *ghcb = svm->sev_es.ghcb; 2536 unsigned int nbits; 2537 2538 /* Re-use the dump_invalid_vmcb module parameter */ 2539 if (!dump_invalid_vmcb) { 2540 pr_warn_ratelimited("set kvm_amd.dump_invalid_vmcb=1 to dump internal KVM state.\n"); 2541 return; 2542 } 2543 2544 nbits = sizeof(ghcb->save.valid_bitmap) * 8; 2545 2546 pr_err("GHCB (GPA=%016llx):\n", svm->vmcb->control.ghcb_gpa); 2547 pr_err("%-20s%016llx is_valid: %u\n", "sw_exit_code", 2548 ghcb->save.sw_exit_code, ghcb_sw_exit_code_is_valid(ghcb)); 2549 pr_err("%-20s%016llx is_valid: %u\n", "sw_exit_info_1", 2550 ghcb->save.sw_exit_info_1, ghcb_sw_exit_info_1_is_valid(ghcb)); 2551 pr_err("%-20s%016llx is_valid: %u\n", "sw_exit_info_2", 2552 ghcb->save.sw_exit_info_2, ghcb_sw_exit_info_2_is_valid(ghcb)); 2553 pr_err("%-20s%016llx is_valid: %u\n", "sw_scratch", 2554 ghcb->save.sw_scratch, ghcb_sw_scratch_is_valid(ghcb)); 2555 pr_err("%-20s%*pb\n", "valid_bitmap", nbits, ghcb->save.valid_bitmap); 2556 } 2557 2558 static void sev_es_sync_to_ghcb(struct vcpu_svm *svm) 2559 { 2560 struct kvm_vcpu *vcpu = &svm->vcpu; 2561 struct ghcb *ghcb = svm->sev_es.ghcb; 2562 2563 /* 2564 * The GHCB protocol so far allows for the following data 2565 * to be returned: 2566 * GPRs RAX, RBX, RCX, RDX 2567 * 2568 * Copy their values, even if they may not have been written during the 2569 * VM-Exit. It's the guest's responsibility to not consume random data. 2570 */ 2571 ghcb_set_rax(ghcb, vcpu->arch.regs[VCPU_REGS_RAX]); 2572 ghcb_set_rbx(ghcb, vcpu->arch.regs[VCPU_REGS_RBX]); 2573 ghcb_set_rcx(ghcb, vcpu->arch.regs[VCPU_REGS_RCX]); 2574 ghcb_set_rdx(ghcb, vcpu->arch.regs[VCPU_REGS_RDX]); 2575 } 2576 2577 static void sev_es_sync_from_ghcb(struct vcpu_svm *svm) 2578 { 2579 struct vmcb_control_area *control = &svm->vmcb->control; 2580 struct kvm_vcpu *vcpu = &svm->vcpu; 2581 struct ghcb *ghcb = svm->sev_es.ghcb; 2582 u64 exit_code; 2583 2584 /* 2585 * The GHCB protocol so far allows for the following data 2586 * to be supplied: 2587 * GPRs RAX, RBX, RCX, RDX 2588 * XCR0 2589 * CPL 2590 * 2591 * VMMCALL allows the guest to provide extra registers. KVM also 2592 * expects RSI for hypercalls, so include that, too. 2593 * 2594 * Copy their values to the appropriate location if supplied. 2595 */ 2596 memset(vcpu->arch.regs, 0, sizeof(vcpu->arch.regs)); 2597 2598 BUILD_BUG_ON(sizeof(svm->sev_es.valid_bitmap) != sizeof(ghcb->save.valid_bitmap)); 2599 memcpy(&svm->sev_es.valid_bitmap, &ghcb->save.valid_bitmap, sizeof(ghcb->save.valid_bitmap)); 2600 2601 vcpu->arch.regs[VCPU_REGS_RAX] = kvm_ghcb_get_rax_if_valid(svm, ghcb); 2602 vcpu->arch.regs[VCPU_REGS_RBX] = kvm_ghcb_get_rbx_if_valid(svm, ghcb); 2603 vcpu->arch.regs[VCPU_REGS_RCX] = kvm_ghcb_get_rcx_if_valid(svm, ghcb); 2604 vcpu->arch.regs[VCPU_REGS_RDX] = kvm_ghcb_get_rdx_if_valid(svm, ghcb); 2605 vcpu->arch.regs[VCPU_REGS_RSI] = kvm_ghcb_get_rsi_if_valid(svm, ghcb); 2606 2607 svm->vmcb->save.cpl = kvm_ghcb_get_cpl_if_valid(svm, ghcb); 2608 2609 if (kvm_ghcb_xcr0_is_valid(svm)) { 2610 vcpu->arch.xcr0 = ghcb_get_xcr0(ghcb); 2611 kvm_update_cpuid_runtime(vcpu); 2612 } 2613 2614 /* Copy the GHCB exit information into the VMCB fields */ 2615 exit_code = ghcb_get_sw_exit_code(ghcb); 2616 control->exit_code = lower_32_bits(exit_code); 2617 control->exit_code_hi = upper_32_bits(exit_code); 2618 control->exit_info_1 = ghcb_get_sw_exit_info_1(ghcb); 2619 control->exit_info_2 = ghcb_get_sw_exit_info_2(ghcb); 2620 svm->sev_es.sw_scratch = kvm_ghcb_get_sw_scratch_if_valid(svm, ghcb); 2621 2622 /* Clear the valid entries fields */ 2623 memset(ghcb->save.valid_bitmap, 0, sizeof(ghcb->save.valid_bitmap)); 2624 } 2625 2626 static u64 kvm_ghcb_get_sw_exit_code(struct vmcb_control_area *control) 2627 { 2628 return (((u64)control->exit_code_hi) << 32) | control->exit_code; 2629 } 2630 2631 static int sev_es_validate_vmgexit(struct vcpu_svm *svm) 2632 { 2633 struct vmcb_control_area *control = &svm->vmcb->control; 2634 struct kvm_vcpu *vcpu = &svm->vcpu; 2635 u64 exit_code; 2636 u64 reason; 2637 2638 /* 2639 * Retrieve the exit code now even though it may not be marked valid 2640 * as it could help with debugging. 2641 */ 2642 exit_code = kvm_ghcb_get_sw_exit_code(control); 2643 2644 /* Only GHCB Usage code 0 is supported */ 2645 if (svm->sev_es.ghcb->ghcb_usage) { 2646 reason = GHCB_ERR_INVALID_USAGE; 2647 goto vmgexit_err; 2648 } 2649 2650 reason = GHCB_ERR_MISSING_INPUT; 2651 2652 if (!kvm_ghcb_sw_exit_code_is_valid(svm) || 2653 !kvm_ghcb_sw_exit_info_1_is_valid(svm) || 2654 !kvm_ghcb_sw_exit_info_2_is_valid(svm)) 2655 goto vmgexit_err; 2656 2657 switch (exit_code) { 2658 case SVM_EXIT_READ_DR7: 2659 break; 2660 case SVM_EXIT_WRITE_DR7: 2661 if (!kvm_ghcb_rax_is_valid(svm)) 2662 goto vmgexit_err; 2663 break; 2664 case SVM_EXIT_RDTSC: 2665 break; 2666 case SVM_EXIT_RDPMC: 2667 if (!kvm_ghcb_rcx_is_valid(svm)) 2668 goto vmgexit_err; 2669 break; 2670 case SVM_EXIT_CPUID: 2671 if (!kvm_ghcb_rax_is_valid(svm) || 2672 !kvm_ghcb_rcx_is_valid(svm)) 2673 goto vmgexit_err; 2674 if (vcpu->arch.regs[VCPU_REGS_RAX] == 0xd) 2675 if (!kvm_ghcb_xcr0_is_valid(svm)) 2676 goto vmgexit_err; 2677 break; 2678 case SVM_EXIT_INVD: 2679 break; 2680 case SVM_EXIT_IOIO: 2681 if (control->exit_info_1 & SVM_IOIO_STR_MASK) { 2682 if (!kvm_ghcb_sw_scratch_is_valid(svm)) 2683 goto vmgexit_err; 2684 } else { 2685 if (!(control->exit_info_1 & SVM_IOIO_TYPE_MASK)) 2686 if (!kvm_ghcb_rax_is_valid(svm)) 2687 goto vmgexit_err; 2688 } 2689 break; 2690 case SVM_EXIT_MSR: 2691 if (!kvm_ghcb_rcx_is_valid(svm)) 2692 goto vmgexit_err; 2693 if (control->exit_info_1) { 2694 if (!kvm_ghcb_rax_is_valid(svm) || 2695 !kvm_ghcb_rdx_is_valid(svm)) 2696 goto vmgexit_err; 2697 } 2698 break; 2699 case SVM_EXIT_VMMCALL: 2700 if (!kvm_ghcb_rax_is_valid(svm) || 2701 !kvm_ghcb_cpl_is_valid(svm)) 2702 goto vmgexit_err; 2703 break; 2704 case SVM_EXIT_RDTSCP: 2705 break; 2706 case SVM_EXIT_WBINVD: 2707 break; 2708 case SVM_EXIT_MONITOR: 2709 if (!kvm_ghcb_rax_is_valid(svm) || 2710 !kvm_ghcb_rcx_is_valid(svm) || 2711 !kvm_ghcb_rdx_is_valid(svm)) 2712 goto vmgexit_err; 2713 break; 2714 case SVM_EXIT_MWAIT: 2715 if (!kvm_ghcb_rax_is_valid(svm) || 2716 !kvm_ghcb_rcx_is_valid(svm)) 2717 goto vmgexit_err; 2718 break; 2719 case SVM_VMGEXIT_MMIO_READ: 2720 case SVM_VMGEXIT_MMIO_WRITE: 2721 if (!kvm_ghcb_sw_scratch_is_valid(svm)) 2722 goto vmgexit_err; 2723 break; 2724 case SVM_VMGEXIT_NMI_COMPLETE: 2725 case SVM_VMGEXIT_AP_HLT_LOOP: 2726 case SVM_VMGEXIT_AP_JUMP_TABLE: 2727 case SVM_VMGEXIT_UNSUPPORTED_EVENT: 2728 case SVM_VMGEXIT_HV_FEATURES: 2729 case SVM_VMGEXIT_TERM_REQUEST: 2730 break; 2731 default: 2732 reason = GHCB_ERR_INVALID_EVENT; 2733 goto vmgexit_err; 2734 } 2735 2736 return 0; 2737 2738 vmgexit_err: 2739 if (reason == GHCB_ERR_INVALID_USAGE) { 2740 vcpu_unimpl(vcpu, "vmgexit: ghcb usage %#x is not valid\n", 2741 svm->sev_es.ghcb->ghcb_usage); 2742 } else if (reason == GHCB_ERR_INVALID_EVENT) { 2743 vcpu_unimpl(vcpu, "vmgexit: exit code %#llx is not valid\n", 2744 exit_code); 2745 } else { 2746 vcpu_unimpl(vcpu, "vmgexit: exit code %#llx input is not valid\n", 2747 exit_code); 2748 dump_ghcb(svm); 2749 } 2750 2751 ghcb_set_sw_exit_info_1(svm->sev_es.ghcb, 2); 2752 ghcb_set_sw_exit_info_2(svm->sev_es.ghcb, reason); 2753 2754 /* Resume the guest to "return" the error code. */ 2755 return 1; 2756 } 2757 2758 void sev_es_unmap_ghcb(struct vcpu_svm *svm) 2759 { 2760 /* Clear any indication that the vCPU is in a type of AP Reset Hold */ 2761 svm->sev_es.ap_reset_hold_type = AP_RESET_HOLD_NONE; 2762 2763 if (!svm->sev_es.ghcb) 2764 return; 2765 2766 if (svm->sev_es.ghcb_sa_free) { 2767 /* 2768 * The scratch area lives outside the GHCB, so there is a 2769 * buffer that, depending on the operation performed, may 2770 * need to be synced, then freed. 2771 */ 2772 if (svm->sev_es.ghcb_sa_sync) { 2773 kvm_write_guest(svm->vcpu.kvm, 2774 svm->sev_es.sw_scratch, 2775 svm->sev_es.ghcb_sa, 2776 svm->sev_es.ghcb_sa_len); 2777 svm->sev_es.ghcb_sa_sync = false; 2778 } 2779 2780 kvfree(svm->sev_es.ghcb_sa); 2781 svm->sev_es.ghcb_sa = NULL; 2782 svm->sev_es.ghcb_sa_free = false; 2783 } 2784 2785 trace_kvm_vmgexit_exit(svm->vcpu.vcpu_id, svm->sev_es.ghcb); 2786 2787 sev_es_sync_to_ghcb(svm); 2788 2789 kvm_vcpu_unmap(&svm->vcpu, &svm->sev_es.ghcb_map, true); 2790 svm->sev_es.ghcb = NULL; 2791 } 2792 2793 void pre_sev_run(struct vcpu_svm *svm, int cpu) 2794 { 2795 struct svm_cpu_data *sd = per_cpu_ptr(&svm_data, cpu); 2796 unsigned int asid = sev_get_asid(svm->vcpu.kvm); 2797 2798 /* Assign the asid allocated with this SEV guest */ 2799 svm->asid = asid; 2800 2801 /* 2802 * Flush guest TLB: 2803 * 2804 * 1) when different VMCB for the same ASID is to be run on the same host CPU. 2805 * 2) or this VMCB was executed on different host CPU in previous VMRUNs. 2806 */ 2807 if (sd->sev_vmcbs[asid] == svm->vmcb && 2808 svm->vcpu.arch.last_vmentry_cpu == cpu) 2809 return; 2810 2811 sd->sev_vmcbs[asid] = svm->vmcb; 2812 svm->vmcb->control.tlb_ctl = TLB_CONTROL_FLUSH_ASID; 2813 vmcb_mark_dirty(svm->vmcb, VMCB_ASID); 2814 } 2815 2816 #define GHCB_SCRATCH_AREA_LIMIT (16ULL * PAGE_SIZE) 2817 static int setup_vmgexit_scratch(struct vcpu_svm *svm, bool sync, u64 len) 2818 { 2819 struct vmcb_control_area *control = &svm->vmcb->control; 2820 u64 ghcb_scratch_beg, ghcb_scratch_end; 2821 u64 scratch_gpa_beg, scratch_gpa_end; 2822 void *scratch_va; 2823 2824 scratch_gpa_beg = svm->sev_es.sw_scratch; 2825 if (!scratch_gpa_beg) { 2826 pr_err("vmgexit: scratch gpa not provided\n"); 2827 goto e_scratch; 2828 } 2829 2830 scratch_gpa_end = scratch_gpa_beg + len; 2831 if (scratch_gpa_end < scratch_gpa_beg) { 2832 pr_err("vmgexit: scratch length (%#llx) not valid for scratch address (%#llx)\n", 2833 len, scratch_gpa_beg); 2834 goto e_scratch; 2835 } 2836 2837 if ((scratch_gpa_beg & PAGE_MASK) == control->ghcb_gpa) { 2838 /* Scratch area begins within GHCB */ 2839 ghcb_scratch_beg = control->ghcb_gpa + 2840 offsetof(struct ghcb, shared_buffer); 2841 ghcb_scratch_end = control->ghcb_gpa + 2842 offsetof(struct ghcb, reserved_0xff0); 2843 2844 /* 2845 * If the scratch area begins within the GHCB, it must be 2846 * completely contained in the GHCB shared buffer area. 2847 */ 2848 if (scratch_gpa_beg < ghcb_scratch_beg || 2849 scratch_gpa_end > ghcb_scratch_end) { 2850 pr_err("vmgexit: scratch area is outside of GHCB shared buffer area (%#llx - %#llx)\n", 2851 scratch_gpa_beg, scratch_gpa_end); 2852 goto e_scratch; 2853 } 2854 2855 scratch_va = (void *)svm->sev_es.ghcb; 2856 scratch_va += (scratch_gpa_beg - control->ghcb_gpa); 2857 } else { 2858 /* 2859 * The guest memory must be read into a kernel buffer, so 2860 * limit the size 2861 */ 2862 if (len > GHCB_SCRATCH_AREA_LIMIT) { 2863 pr_err("vmgexit: scratch area exceeds KVM limits (%#llx requested, %#llx limit)\n", 2864 len, GHCB_SCRATCH_AREA_LIMIT); 2865 goto e_scratch; 2866 } 2867 scratch_va = kvzalloc(len, GFP_KERNEL_ACCOUNT); 2868 if (!scratch_va) 2869 return -ENOMEM; 2870 2871 if (kvm_read_guest(svm->vcpu.kvm, scratch_gpa_beg, scratch_va, len)) { 2872 /* Unable to copy scratch area from guest */ 2873 pr_err("vmgexit: kvm_read_guest for scratch area failed\n"); 2874 2875 kvfree(scratch_va); 2876 return -EFAULT; 2877 } 2878 2879 /* 2880 * The scratch area is outside the GHCB. The operation will 2881 * dictate whether the buffer needs to be synced before running 2882 * the vCPU next time (i.e. a read was requested so the data 2883 * must be written back to the guest memory). 2884 */ 2885 svm->sev_es.ghcb_sa_sync = sync; 2886 svm->sev_es.ghcb_sa_free = true; 2887 } 2888 2889 svm->sev_es.ghcb_sa = scratch_va; 2890 svm->sev_es.ghcb_sa_len = len; 2891 2892 return 0; 2893 2894 e_scratch: 2895 ghcb_set_sw_exit_info_1(svm->sev_es.ghcb, 2); 2896 ghcb_set_sw_exit_info_2(svm->sev_es.ghcb, GHCB_ERR_INVALID_SCRATCH_AREA); 2897 2898 return 1; 2899 } 2900 2901 static void set_ghcb_msr_bits(struct vcpu_svm *svm, u64 value, u64 mask, 2902 unsigned int pos) 2903 { 2904 svm->vmcb->control.ghcb_gpa &= ~(mask << pos); 2905 svm->vmcb->control.ghcb_gpa |= (value & mask) << pos; 2906 } 2907 2908 static u64 get_ghcb_msr_bits(struct vcpu_svm *svm, u64 mask, unsigned int pos) 2909 { 2910 return (svm->vmcb->control.ghcb_gpa >> pos) & mask; 2911 } 2912 2913 static void set_ghcb_msr(struct vcpu_svm *svm, u64 value) 2914 { 2915 svm->vmcb->control.ghcb_gpa = value; 2916 } 2917 2918 static int sev_handle_vmgexit_msr_protocol(struct vcpu_svm *svm) 2919 { 2920 struct vmcb_control_area *control = &svm->vmcb->control; 2921 struct kvm_vcpu *vcpu = &svm->vcpu; 2922 struct kvm_sev_info *sev = &to_kvm_svm(vcpu->kvm)->sev_info; 2923 u64 ghcb_info; 2924 int ret = 1; 2925 2926 ghcb_info = control->ghcb_gpa & GHCB_MSR_INFO_MASK; 2927 2928 trace_kvm_vmgexit_msr_protocol_enter(svm->vcpu.vcpu_id, 2929 control->ghcb_gpa); 2930 2931 switch (ghcb_info) { 2932 case GHCB_MSR_SEV_INFO_REQ: 2933 set_ghcb_msr(svm, GHCB_MSR_SEV_INFO((__u64)sev->ghcb_version, 2934 GHCB_VERSION_MIN, 2935 sev_enc_bit)); 2936 break; 2937 case GHCB_MSR_CPUID_REQ: { 2938 u64 cpuid_fn, cpuid_reg, cpuid_value; 2939 2940 cpuid_fn = get_ghcb_msr_bits(svm, 2941 GHCB_MSR_CPUID_FUNC_MASK, 2942 GHCB_MSR_CPUID_FUNC_POS); 2943 2944 /* Initialize the registers needed by the CPUID intercept */ 2945 vcpu->arch.regs[VCPU_REGS_RAX] = cpuid_fn; 2946 vcpu->arch.regs[VCPU_REGS_RCX] = 0; 2947 2948 ret = svm_invoke_exit_handler(vcpu, SVM_EXIT_CPUID); 2949 if (!ret) { 2950 /* Error, keep GHCB MSR value as-is */ 2951 break; 2952 } 2953 2954 cpuid_reg = get_ghcb_msr_bits(svm, 2955 GHCB_MSR_CPUID_REG_MASK, 2956 GHCB_MSR_CPUID_REG_POS); 2957 if (cpuid_reg == 0) 2958 cpuid_value = vcpu->arch.regs[VCPU_REGS_RAX]; 2959 else if (cpuid_reg == 1) 2960 cpuid_value = vcpu->arch.regs[VCPU_REGS_RBX]; 2961 else if (cpuid_reg == 2) 2962 cpuid_value = vcpu->arch.regs[VCPU_REGS_RCX]; 2963 else 2964 cpuid_value = vcpu->arch.regs[VCPU_REGS_RDX]; 2965 2966 set_ghcb_msr_bits(svm, cpuid_value, 2967 GHCB_MSR_CPUID_VALUE_MASK, 2968 GHCB_MSR_CPUID_VALUE_POS); 2969 2970 set_ghcb_msr_bits(svm, GHCB_MSR_CPUID_RESP, 2971 GHCB_MSR_INFO_MASK, 2972 GHCB_MSR_INFO_POS); 2973 break; 2974 } 2975 case GHCB_MSR_AP_RESET_HOLD_REQ: 2976 svm->sev_es.ap_reset_hold_type = AP_RESET_HOLD_MSR_PROTO; 2977 ret = kvm_emulate_ap_reset_hold(&svm->vcpu); 2978 2979 /* 2980 * Preset the result to a non-SIPI return and then only set 2981 * the result to non-zero when delivering a SIPI. 2982 */ 2983 set_ghcb_msr_bits(svm, 0, 2984 GHCB_MSR_AP_RESET_HOLD_RESULT_MASK, 2985 GHCB_MSR_AP_RESET_HOLD_RESULT_POS); 2986 2987 set_ghcb_msr_bits(svm, GHCB_MSR_AP_RESET_HOLD_RESP, 2988 GHCB_MSR_INFO_MASK, 2989 GHCB_MSR_INFO_POS); 2990 break; 2991 case GHCB_MSR_HV_FT_REQ: 2992 set_ghcb_msr_bits(svm, GHCB_HV_FT_SUPPORTED, 2993 GHCB_MSR_HV_FT_MASK, GHCB_MSR_HV_FT_POS); 2994 set_ghcb_msr_bits(svm, GHCB_MSR_HV_FT_RESP, 2995 GHCB_MSR_INFO_MASK, GHCB_MSR_INFO_POS); 2996 break; 2997 case GHCB_MSR_TERM_REQ: { 2998 u64 reason_set, reason_code; 2999 3000 reason_set = get_ghcb_msr_bits(svm, 3001 GHCB_MSR_TERM_REASON_SET_MASK, 3002 GHCB_MSR_TERM_REASON_SET_POS); 3003 reason_code = get_ghcb_msr_bits(svm, 3004 GHCB_MSR_TERM_REASON_MASK, 3005 GHCB_MSR_TERM_REASON_POS); 3006 pr_info("SEV-ES guest requested termination: %#llx:%#llx\n", 3007 reason_set, reason_code); 3008 3009 vcpu->run->exit_reason = KVM_EXIT_SYSTEM_EVENT; 3010 vcpu->run->system_event.type = KVM_SYSTEM_EVENT_SEV_TERM; 3011 vcpu->run->system_event.ndata = 1; 3012 vcpu->run->system_event.data[0] = control->ghcb_gpa; 3013 3014 return 0; 3015 } 3016 default: 3017 /* Error, keep GHCB MSR value as-is */ 3018 break; 3019 } 3020 3021 trace_kvm_vmgexit_msr_protocol_exit(svm->vcpu.vcpu_id, 3022 control->ghcb_gpa, ret); 3023 3024 return ret; 3025 } 3026 3027 int sev_handle_vmgexit(struct kvm_vcpu *vcpu) 3028 { 3029 struct vcpu_svm *svm = to_svm(vcpu); 3030 struct vmcb_control_area *control = &svm->vmcb->control; 3031 u64 ghcb_gpa, exit_code; 3032 int ret; 3033 3034 /* Validate the GHCB */ 3035 ghcb_gpa = control->ghcb_gpa; 3036 if (ghcb_gpa & GHCB_MSR_INFO_MASK) 3037 return sev_handle_vmgexit_msr_protocol(svm); 3038 3039 if (!ghcb_gpa) { 3040 vcpu_unimpl(vcpu, "vmgexit: GHCB gpa is not set\n"); 3041 3042 /* Without a GHCB, just return right back to the guest */ 3043 return 1; 3044 } 3045 3046 if (kvm_vcpu_map(vcpu, ghcb_gpa >> PAGE_SHIFT, &svm->sev_es.ghcb_map)) { 3047 /* Unable to map GHCB from guest */ 3048 vcpu_unimpl(vcpu, "vmgexit: error mapping GHCB [%#llx] from guest\n", 3049 ghcb_gpa); 3050 3051 /* Without a GHCB, just return right back to the guest */ 3052 return 1; 3053 } 3054 3055 svm->sev_es.ghcb = svm->sev_es.ghcb_map.hva; 3056 3057 trace_kvm_vmgexit_enter(vcpu->vcpu_id, svm->sev_es.ghcb); 3058 3059 sev_es_sync_from_ghcb(svm); 3060 ret = sev_es_validate_vmgexit(svm); 3061 if (ret) 3062 return ret; 3063 3064 ghcb_set_sw_exit_info_1(svm->sev_es.ghcb, 0); 3065 ghcb_set_sw_exit_info_2(svm->sev_es.ghcb, 0); 3066 3067 exit_code = kvm_ghcb_get_sw_exit_code(control); 3068 switch (exit_code) { 3069 case SVM_VMGEXIT_MMIO_READ: 3070 ret = setup_vmgexit_scratch(svm, true, control->exit_info_2); 3071 if (ret) 3072 break; 3073 3074 ret = kvm_sev_es_mmio_read(vcpu, 3075 control->exit_info_1, 3076 control->exit_info_2, 3077 svm->sev_es.ghcb_sa); 3078 break; 3079 case SVM_VMGEXIT_MMIO_WRITE: 3080 ret = setup_vmgexit_scratch(svm, false, control->exit_info_2); 3081 if (ret) 3082 break; 3083 3084 ret = kvm_sev_es_mmio_write(vcpu, 3085 control->exit_info_1, 3086 control->exit_info_2, 3087 svm->sev_es.ghcb_sa); 3088 break; 3089 case SVM_VMGEXIT_NMI_COMPLETE: 3090 ++vcpu->stat.nmi_window_exits; 3091 svm->nmi_masked = false; 3092 kvm_make_request(KVM_REQ_EVENT, vcpu); 3093 ret = 1; 3094 break; 3095 case SVM_VMGEXIT_AP_HLT_LOOP: 3096 svm->sev_es.ap_reset_hold_type = AP_RESET_HOLD_NAE_EVENT; 3097 ret = kvm_emulate_ap_reset_hold(vcpu); 3098 break; 3099 case SVM_VMGEXIT_AP_JUMP_TABLE: { 3100 struct kvm_sev_info *sev = &to_kvm_svm(vcpu->kvm)->sev_info; 3101 3102 switch (control->exit_info_1) { 3103 case 0: 3104 /* Set AP jump table address */ 3105 sev->ap_jump_table = control->exit_info_2; 3106 break; 3107 case 1: 3108 /* Get AP jump table address */ 3109 ghcb_set_sw_exit_info_2(svm->sev_es.ghcb, sev->ap_jump_table); 3110 break; 3111 default: 3112 pr_err("svm: vmgexit: unsupported AP jump table request - exit_info_1=%#llx\n", 3113 control->exit_info_1); 3114 ghcb_set_sw_exit_info_1(svm->sev_es.ghcb, 2); 3115 ghcb_set_sw_exit_info_2(svm->sev_es.ghcb, GHCB_ERR_INVALID_INPUT); 3116 } 3117 3118 ret = 1; 3119 break; 3120 } 3121 case SVM_VMGEXIT_HV_FEATURES: 3122 ghcb_set_sw_exit_info_2(svm->sev_es.ghcb, GHCB_HV_FT_SUPPORTED); 3123 3124 ret = 1; 3125 break; 3126 case SVM_VMGEXIT_TERM_REQUEST: 3127 pr_info("SEV-ES guest requested termination: reason %#llx info %#llx\n", 3128 control->exit_info_1, control->exit_info_2); 3129 vcpu->run->exit_reason = KVM_EXIT_SYSTEM_EVENT; 3130 vcpu->run->system_event.type = KVM_SYSTEM_EVENT_SEV_TERM; 3131 vcpu->run->system_event.ndata = 1; 3132 vcpu->run->system_event.data[0] = control->ghcb_gpa; 3133 break; 3134 case SVM_VMGEXIT_UNSUPPORTED_EVENT: 3135 vcpu_unimpl(vcpu, 3136 "vmgexit: unsupported event - exit_info_1=%#llx, exit_info_2=%#llx\n", 3137 control->exit_info_1, control->exit_info_2); 3138 ret = -EINVAL; 3139 break; 3140 default: 3141 ret = svm_invoke_exit_handler(vcpu, exit_code); 3142 } 3143 3144 return ret; 3145 } 3146 3147 int sev_es_string_io(struct vcpu_svm *svm, int size, unsigned int port, int in) 3148 { 3149 int count; 3150 int bytes; 3151 int r; 3152 3153 if (svm->vmcb->control.exit_info_2 > INT_MAX) 3154 return -EINVAL; 3155 3156 count = svm->vmcb->control.exit_info_2; 3157 if (unlikely(check_mul_overflow(count, size, &bytes))) 3158 return -EINVAL; 3159 3160 r = setup_vmgexit_scratch(svm, in, bytes); 3161 if (r) 3162 return r; 3163 3164 return kvm_sev_es_string_io(&svm->vcpu, size, port, svm->sev_es.ghcb_sa, 3165 count, in); 3166 } 3167 3168 static void sev_es_vcpu_after_set_cpuid(struct vcpu_svm *svm) 3169 { 3170 struct kvm_vcpu *vcpu = &svm->vcpu; 3171 3172 if (boot_cpu_has(X86_FEATURE_V_TSC_AUX)) { 3173 bool v_tsc_aux = guest_cpuid_has(vcpu, X86_FEATURE_RDTSCP) || 3174 guest_cpuid_has(vcpu, X86_FEATURE_RDPID); 3175 3176 set_msr_interception(vcpu, svm->msrpm, MSR_TSC_AUX, v_tsc_aux, v_tsc_aux); 3177 } 3178 3179 /* 3180 * For SEV-ES, accesses to MSR_IA32_XSS should not be intercepted if 3181 * the host/guest supports its use. 3182 * 3183 * guest_can_use() checks a number of requirements on the host/guest to 3184 * ensure that MSR_IA32_XSS is available, but it might report true even 3185 * if X86_FEATURE_XSAVES isn't configured in the guest to ensure host 3186 * MSR_IA32_XSS is always properly restored. For SEV-ES, it is better 3187 * to further check that the guest CPUID actually supports 3188 * X86_FEATURE_XSAVES so that accesses to MSR_IA32_XSS by misbehaved 3189 * guests will still get intercepted and caught in the normal 3190 * kvm_emulate_rdmsr()/kvm_emulated_wrmsr() paths. 3191 */ 3192 if (guest_can_use(vcpu, X86_FEATURE_XSAVES) && 3193 guest_cpuid_has(vcpu, X86_FEATURE_XSAVES)) 3194 set_msr_interception(vcpu, svm->msrpm, MSR_IA32_XSS, 1, 1); 3195 else 3196 set_msr_interception(vcpu, svm->msrpm, MSR_IA32_XSS, 0, 0); 3197 } 3198 3199 void sev_vcpu_after_set_cpuid(struct vcpu_svm *svm) 3200 { 3201 struct kvm_vcpu *vcpu = &svm->vcpu; 3202 struct kvm_cpuid_entry2 *best; 3203 3204 /* For sev guests, the memory encryption bit is not reserved in CR3. */ 3205 best = kvm_find_cpuid_entry(vcpu, 0x8000001F); 3206 if (best) 3207 vcpu->arch.reserved_gpa_bits &= ~(1UL << (best->ebx & 0x3f)); 3208 3209 if (sev_es_guest(svm->vcpu.kvm)) 3210 sev_es_vcpu_after_set_cpuid(svm); 3211 } 3212 3213 static void sev_es_init_vmcb(struct vcpu_svm *svm) 3214 { 3215 struct vmcb *vmcb = svm->vmcb01.ptr; 3216 struct kvm_vcpu *vcpu = &svm->vcpu; 3217 3218 svm->vmcb->control.nested_ctl |= SVM_NESTED_CTL_SEV_ES_ENABLE; 3219 svm->vmcb->control.virt_ext |= LBR_CTL_ENABLE_MASK; 3220 3221 /* 3222 * An SEV-ES guest requires a VMSA area that is a separate from the 3223 * VMCB page. Do not include the encryption mask on the VMSA physical 3224 * address since hardware will access it using the guest key. Note, 3225 * the VMSA will be NULL if this vCPU is the destination for intrahost 3226 * migration, and will be copied later. 3227 */ 3228 if (svm->sev_es.vmsa) 3229 svm->vmcb->control.vmsa_pa = __pa(svm->sev_es.vmsa); 3230 3231 /* Can't intercept CR register access, HV can't modify CR registers */ 3232 svm_clr_intercept(svm, INTERCEPT_CR0_READ); 3233 svm_clr_intercept(svm, INTERCEPT_CR4_READ); 3234 svm_clr_intercept(svm, INTERCEPT_CR8_READ); 3235 svm_clr_intercept(svm, INTERCEPT_CR0_WRITE); 3236 svm_clr_intercept(svm, INTERCEPT_CR4_WRITE); 3237 svm_clr_intercept(svm, INTERCEPT_CR8_WRITE); 3238 3239 svm_clr_intercept(svm, INTERCEPT_SELECTIVE_CR0); 3240 3241 /* Track EFER/CR register changes */ 3242 svm_set_intercept(svm, TRAP_EFER_WRITE); 3243 svm_set_intercept(svm, TRAP_CR0_WRITE); 3244 svm_set_intercept(svm, TRAP_CR4_WRITE); 3245 svm_set_intercept(svm, TRAP_CR8_WRITE); 3246 3247 vmcb->control.intercepts[INTERCEPT_DR] = 0; 3248 if (!sev_vcpu_has_debug_swap(svm)) { 3249 vmcb_set_intercept(&vmcb->control, INTERCEPT_DR7_READ); 3250 vmcb_set_intercept(&vmcb->control, INTERCEPT_DR7_WRITE); 3251 recalc_intercepts(svm); 3252 } else { 3253 /* 3254 * Disable #DB intercept iff DebugSwap is enabled. KVM doesn't 3255 * allow debugging SEV-ES guests, and enables DebugSwap iff 3256 * NO_NESTED_DATA_BP is supported, so there's no reason to 3257 * intercept #DB when DebugSwap is enabled. For simplicity 3258 * with respect to guest debug, intercept #DB for other VMs 3259 * even if NO_NESTED_DATA_BP is supported, i.e. even if the 3260 * guest can't DoS the CPU with infinite #DB vectoring. 3261 */ 3262 clr_exception_intercept(svm, DB_VECTOR); 3263 } 3264 3265 /* Can't intercept XSETBV, HV can't modify XCR0 directly */ 3266 svm_clr_intercept(svm, INTERCEPT_XSETBV); 3267 3268 /* Clear intercepts on selected MSRs */ 3269 set_msr_interception(vcpu, svm->msrpm, MSR_EFER, 1, 1); 3270 set_msr_interception(vcpu, svm->msrpm, MSR_IA32_CR_PAT, 1, 1); 3271 set_msr_interception(vcpu, svm->msrpm, MSR_IA32_LASTBRANCHFROMIP, 1, 1); 3272 set_msr_interception(vcpu, svm->msrpm, MSR_IA32_LASTBRANCHTOIP, 1, 1); 3273 set_msr_interception(vcpu, svm->msrpm, MSR_IA32_LASTINTFROMIP, 1, 1); 3274 set_msr_interception(vcpu, svm->msrpm, MSR_IA32_LASTINTTOIP, 1, 1); 3275 } 3276 3277 void sev_init_vmcb(struct vcpu_svm *svm) 3278 { 3279 svm->vmcb->control.nested_ctl |= SVM_NESTED_CTL_SEV_ENABLE; 3280 clr_exception_intercept(svm, UD_VECTOR); 3281 3282 /* 3283 * Don't intercept #GP for SEV guests, e.g. for the VMware backdoor, as 3284 * KVM can't decrypt guest memory to decode the faulting instruction. 3285 */ 3286 clr_exception_intercept(svm, GP_VECTOR); 3287 3288 if (sev_es_guest(svm->vcpu.kvm)) 3289 sev_es_init_vmcb(svm); 3290 } 3291 3292 void sev_es_vcpu_reset(struct vcpu_svm *svm) 3293 { 3294 struct kvm_vcpu *vcpu = &svm->vcpu; 3295 struct kvm_sev_info *sev = &to_kvm_svm(vcpu->kvm)->sev_info; 3296 3297 /* 3298 * Set the GHCB MSR value as per the GHCB specification when emulating 3299 * vCPU RESET for an SEV-ES guest. 3300 */ 3301 set_ghcb_msr(svm, GHCB_MSR_SEV_INFO((__u64)sev->ghcb_version, 3302 GHCB_VERSION_MIN, 3303 sev_enc_bit)); 3304 } 3305 3306 void sev_es_prepare_switch_to_guest(struct vcpu_svm *svm, struct sev_es_save_area *hostsa) 3307 { 3308 /* 3309 * All host state for SEV-ES guests is categorized into three swap types 3310 * based on how it is handled by hardware during a world switch: 3311 * 3312 * A: VMRUN: Host state saved in host save area 3313 * VMEXIT: Host state loaded from host save area 3314 * 3315 * B: VMRUN: Host state _NOT_ saved in host save area 3316 * VMEXIT: Host state loaded from host save area 3317 * 3318 * C: VMRUN: Host state _NOT_ saved in host save area 3319 * VMEXIT: Host state initialized to default(reset) values 3320 * 3321 * Manually save type-B state, i.e. state that is loaded by VMEXIT but 3322 * isn't saved by VMRUN, that isn't already saved by VMSAVE (performed 3323 * by common SVM code). 3324 */ 3325 hostsa->xcr0 = xgetbv(XCR_XFEATURE_ENABLED_MASK); 3326 hostsa->pkru = read_pkru(); 3327 hostsa->xss = host_xss; 3328 3329 /* 3330 * If DebugSwap is enabled, debug registers are loaded but NOT saved by 3331 * the CPU (Type-B). If DebugSwap is disabled/unsupported, the CPU both 3332 * saves and loads debug registers (Type-A). 3333 */ 3334 if (sev_vcpu_has_debug_swap(svm)) { 3335 hostsa->dr0 = native_get_debugreg(0); 3336 hostsa->dr1 = native_get_debugreg(1); 3337 hostsa->dr2 = native_get_debugreg(2); 3338 hostsa->dr3 = native_get_debugreg(3); 3339 hostsa->dr0_addr_mask = amd_get_dr_addr_mask(0); 3340 hostsa->dr1_addr_mask = amd_get_dr_addr_mask(1); 3341 hostsa->dr2_addr_mask = amd_get_dr_addr_mask(2); 3342 hostsa->dr3_addr_mask = amd_get_dr_addr_mask(3); 3343 } 3344 } 3345 3346 void sev_vcpu_deliver_sipi_vector(struct kvm_vcpu *vcpu, u8 vector) 3347 { 3348 struct vcpu_svm *svm = to_svm(vcpu); 3349 3350 /* First SIPI: Use the values as initially set by the VMM */ 3351 if (!svm->sev_es.received_first_sipi) { 3352 svm->sev_es.received_first_sipi = true; 3353 return; 3354 } 3355 3356 /* Subsequent SIPI */ 3357 switch (svm->sev_es.ap_reset_hold_type) { 3358 case AP_RESET_HOLD_NAE_EVENT: 3359 /* 3360 * Return from an AP Reset Hold VMGEXIT, where the guest will 3361 * set the CS and RIP. Set SW_EXIT_INFO_2 to a non-zero value. 3362 */ 3363 ghcb_set_sw_exit_info_2(svm->sev_es.ghcb, 1); 3364 break; 3365 case AP_RESET_HOLD_MSR_PROTO: 3366 /* 3367 * Return from an AP Reset Hold VMGEXIT, where the guest will 3368 * set the CS and RIP. Set GHCB data field to a non-zero value. 3369 */ 3370 set_ghcb_msr_bits(svm, 1, 3371 GHCB_MSR_AP_RESET_HOLD_RESULT_MASK, 3372 GHCB_MSR_AP_RESET_HOLD_RESULT_POS); 3373 3374 set_ghcb_msr_bits(svm, GHCB_MSR_AP_RESET_HOLD_RESP, 3375 GHCB_MSR_INFO_MASK, 3376 GHCB_MSR_INFO_POS); 3377 break; 3378 default: 3379 break; 3380 } 3381 } 3382 3383 struct page *snp_safe_alloc_page(struct kvm_vcpu *vcpu) 3384 { 3385 unsigned long pfn; 3386 struct page *p; 3387 3388 if (!cc_platform_has(CC_ATTR_HOST_SEV_SNP)) 3389 return alloc_page(GFP_KERNEL_ACCOUNT | __GFP_ZERO); 3390 3391 /* 3392 * Allocate an SNP-safe page to workaround the SNP erratum where 3393 * the CPU will incorrectly signal an RMP violation #PF if a 3394 * hugepage (2MB or 1GB) collides with the RMP entry of a 3395 * 2MB-aligned VMCB, VMSA, or AVIC backing page. 3396 * 3397 * Allocate one extra page, choose a page which is not 3398 * 2MB-aligned, and free the other. 3399 */ 3400 p = alloc_pages(GFP_KERNEL_ACCOUNT | __GFP_ZERO, 1); 3401 if (!p) 3402 return NULL; 3403 3404 split_page(p, 1); 3405 3406 pfn = page_to_pfn(p); 3407 if (IS_ALIGNED(pfn, PTRS_PER_PMD)) 3408 __free_page(p++); 3409 else 3410 __free_page(p + 1); 3411 3412 return p; 3413 } 3414