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/debugreg.h> 27 28 #include "mmu.h" 29 #include "x86.h" 30 #include "svm.h" 31 #include "svm_ops.h" 32 #include "cpuid.h" 33 #include "trace.h" 34 35 #ifndef CONFIG_KVM_AMD_SEV 36 /* 37 * When this config is not defined, SEV feature is not supported and APIs in 38 * this file are not used but this file still gets compiled into the KVM AMD 39 * module. 40 * 41 * We will not have MISC_CG_RES_SEV and MISC_CG_RES_SEV_ES entries in the enum 42 * misc_res_type {} defined in linux/misc_cgroup.h. 43 * 44 * Below macros allow compilation to succeed. 45 */ 46 #define MISC_CG_RES_SEV MISC_CG_RES_TYPES 47 #define MISC_CG_RES_SEV_ES MISC_CG_RES_TYPES 48 #endif 49 50 #ifdef CONFIG_KVM_AMD_SEV 51 /* enable/disable SEV support */ 52 static bool sev_enabled = true; 53 module_param_named(sev, sev_enabled, bool, 0444); 54 55 /* enable/disable SEV-ES support */ 56 static bool sev_es_enabled = true; 57 module_param_named(sev_es, sev_es_enabled, bool, 0444); 58 59 /* enable/disable SEV-ES DebugSwap support */ 60 static bool sev_es_debug_swap_enabled = false; 61 module_param_named(debug_swap, sev_es_debug_swap_enabled, bool, 0444); 62 #else 63 #define sev_enabled false 64 #define sev_es_enabled false 65 #define sev_es_debug_swap_enabled false 66 #endif /* CONFIG_KVM_AMD_SEV */ 67 68 static u8 sev_enc_bit; 69 static DECLARE_RWSEM(sev_deactivate_lock); 70 static DEFINE_MUTEX(sev_bitmap_lock); 71 unsigned int max_sev_asid; 72 static unsigned int min_sev_asid; 73 static unsigned long sev_me_mask; 74 static unsigned int nr_asids; 75 static unsigned long *sev_asid_bitmap; 76 static unsigned long *sev_reclaim_asid_bitmap; 77 78 struct enc_region { 79 struct list_head list; 80 unsigned long npages; 81 struct page **pages; 82 unsigned long uaddr; 83 unsigned long size; 84 }; 85 86 /* Called with the sev_bitmap_lock held, or on shutdown */ 87 static int sev_flush_asids(unsigned int min_asid, unsigned int max_asid) 88 { 89 int ret, error = 0; 90 unsigned int asid; 91 92 /* Check if there are any ASIDs to reclaim before performing a flush */ 93 asid = find_next_bit(sev_reclaim_asid_bitmap, nr_asids, min_asid); 94 if (asid > max_asid) 95 return -EBUSY; 96 97 /* 98 * DEACTIVATE will clear the WBINVD indicator causing DF_FLUSH to fail, 99 * so it must be guarded. 100 */ 101 down_write(&sev_deactivate_lock); 102 103 wbinvd_on_all_cpus(); 104 ret = sev_guest_df_flush(&error); 105 106 up_write(&sev_deactivate_lock); 107 108 if (ret) 109 pr_err("SEV: DF_FLUSH failed, ret=%d, error=%#x\n", ret, error); 110 111 return ret; 112 } 113 114 static inline bool is_mirroring_enc_context(struct kvm *kvm) 115 { 116 return !!to_kvm_svm(kvm)->sev_info.enc_context_owner; 117 } 118 119 /* Must be called with the sev_bitmap_lock held */ 120 static bool __sev_recycle_asids(unsigned int min_asid, unsigned int max_asid) 121 { 122 if (sev_flush_asids(min_asid, max_asid)) 123 return false; 124 125 /* The flush process will flush all reclaimable SEV and SEV-ES ASIDs */ 126 bitmap_xor(sev_asid_bitmap, sev_asid_bitmap, sev_reclaim_asid_bitmap, 127 nr_asids); 128 bitmap_zero(sev_reclaim_asid_bitmap, nr_asids); 129 130 return true; 131 } 132 133 static int sev_misc_cg_try_charge(struct kvm_sev_info *sev) 134 { 135 enum misc_res_type type = sev->es_active ? MISC_CG_RES_SEV_ES : MISC_CG_RES_SEV; 136 return misc_cg_try_charge(type, sev->misc_cg, 1); 137 } 138 139 static void sev_misc_cg_uncharge(struct kvm_sev_info *sev) 140 { 141 enum misc_res_type type = sev->es_active ? MISC_CG_RES_SEV_ES : MISC_CG_RES_SEV; 142 misc_cg_uncharge(type, sev->misc_cg, 1); 143 } 144 145 static int sev_asid_new(struct kvm_sev_info *sev) 146 { 147 /* 148 * SEV-enabled guests must use asid from min_sev_asid to max_sev_asid. 149 * SEV-ES-enabled guest can use from 1 to min_sev_asid - 1. 150 * Note: min ASID can end up larger than the max if basic SEV support is 151 * effectively disabled by disallowing use of ASIDs for SEV guests. 152 */ 153 unsigned int min_asid = sev->es_active ? 1 : min_sev_asid; 154 unsigned int max_asid = sev->es_active ? min_sev_asid - 1 : max_sev_asid; 155 unsigned int asid; 156 bool retry = true; 157 int ret; 158 159 if (min_asid > max_asid) 160 return -ENOTTY; 161 162 WARN_ON(sev->misc_cg); 163 sev->misc_cg = get_current_misc_cg(); 164 ret = sev_misc_cg_try_charge(sev); 165 if (ret) { 166 put_misc_cg(sev->misc_cg); 167 sev->misc_cg = NULL; 168 return ret; 169 } 170 171 mutex_lock(&sev_bitmap_lock); 172 173 again: 174 asid = find_next_zero_bit(sev_asid_bitmap, max_asid + 1, min_asid); 175 if (asid > max_asid) { 176 if (retry && __sev_recycle_asids(min_asid, max_asid)) { 177 retry = false; 178 goto again; 179 } 180 mutex_unlock(&sev_bitmap_lock); 181 ret = -EBUSY; 182 goto e_uncharge; 183 } 184 185 __set_bit(asid, sev_asid_bitmap); 186 187 mutex_unlock(&sev_bitmap_lock); 188 189 return asid; 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 { 255 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 256 int asid, ret; 257 258 if (kvm->created_vcpus) 259 return -EINVAL; 260 261 ret = -EBUSY; 262 if (unlikely(sev->active)) 263 return ret; 264 265 sev->active = true; 266 sev->es_active = argp->id == KVM_SEV_ES_INIT; 267 asid = sev_asid_new(sev); 268 if (asid < 0) 269 goto e_no_asid; 270 sev->asid = asid; 271 272 ret = sev_platform_init(&argp->error); 273 if (ret) 274 goto e_free; 275 276 INIT_LIST_HEAD(&sev->regions_list); 277 INIT_LIST_HEAD(&sev->mirror_vms); 278 279 kvm_set_apicv_inhibit(kvm, APICV_INHIBIT_REASON_SEV); 280 281 return 0; 282 283 e_free: 284 sev_asid_free(sev); 285 sev->asid = 0; 286 e_no_asid: 287 sev->es_active = false; 288 sev->active = false; 289 return ret; 290 } 291 292 static int sev_bind_asid(struct kvm *kvm, unsigned int handle, int *error) 293 { 294 unsigned int asid = sev_get_asid(kvm); 295 struct sev_data_activate activate; 296 int ret; 297 298 /* activate ASID on the given handle */ 299 activate.handle = handle; 300 activate.asid = asid; 301 ret = sev_guest_activate(&activate, error); 302 303 return ret; 304 } 305 306 static int __sev_issue_cmd(int fd, int id, void *data, int *error) 307 { 308 struct fd f; 309 int ret; 310 311 f = fdget(fd); 312 if (!f.file) 313 return -EBADF; 314 315 ret = sev_issue_cmd_external_user(f.file, id, data, error); 316 317 fdput(f); 318 return ret; 319 } 320 321 static int sev_issue_cmd(struct kvm *kvm, int id, void *data, int *error) 322 { 323 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 324 325 return __sev_issue_cmd(sev->fd, id, data, error); 326 } 327 328 static int sev_launch_start(struct kvm *kvm, struct kvm_sev_cmd *argp) 329 { 330 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 331 struct sev_data_launch_start start; 332 struct kvm_sev_launch_start params; 333 void *dh_blob, *session_blob; 334 int *error = &argp->error; 335 int ret; 336 337 if (!sev_guest(kvm)) 338 return -ENOTTY; 339 340 if (copy_from_user(¶ms, (void __user *)(uintptr_t)argp->data, sizeof(params))) 341 return -EFAULT; 342 343 memset(&start, 0, sizeof(start)); 344 345 dh_blob = NULL; 346 if (params.dh_uaddr) { 347 dh_blob = psp_copy_user_blob(params.dh_uaddr, params.dh_len); 348 if (IS_ERR(dh_blob)) 349 return PTR_ERR(dh_blob); 350 351 start.dh_cert_address = __sme_set(__pa(dh_blob)); 352 start.dh_cert_len = params.dh_len; 353 } 354 355 session_blob = NULL; 356 if (params.session_uaddr) { 357 session_blob = psp_copy_user_blob(params.session_uaddr, params.session_len); 358 if (IS_ERR(session_blob)) { 359 ret = PTR_ERR(session_blob); 360 goto e_free_dh; 361 } 362 363 start.session_address = __sme_set(__pa(session_blob)); 364 start.session_len = params.session_len; 365 } 366 367 start.handle = params.handle; 368 start.policy = params.policy; 369 370 /* create memory encryption context */ 371 ret = __sev_issue_cmd(argp->sev_fd, SEV_CMD_LAUNCH_START, &start, error); 372 if (ret) 373 goto e_free_session; 374 375 /* Bind ASID to this guest */ 376 ret = sev_bind_asid(kvm, start.handle, error); 377 if (ret) { 378 sev_decommission(start.handle); 379 goto e_free_session; 380 } 381 382 /* return handle to userspace */ 383 params.handle = start.handle; 384 if (copy_to_user((void __user *)(uintptr_t)argp->data, ¶ms, sizeof(params))) { 385 sev_unbind_asid(kvm, start.handle); 386 ret = -EFAULT; 387 goto e_free_session; 388 } 389 390 sev->handle = start.handle; 391 sev->fd = argp->sev_fd; 392 393 e_free_session: 394 kfree(session_blob); 395 e_free_dh: 396 kfree(dh_blob); 397 return ret; 398 } 399 400 static struct page **sev_pin_memory(struct kvm *kvm, unsigned long uaddr, 401 unsigned long ulen, unsigned long *n, 402 int write) 403 { 404 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 405 unsigned long npages, size; 406 int npinned; 407 unsigned long locked, lock_limit; 408 struct page **pages; 409 unsigned long first, last; 410 int ret; 411 412 lockdep_assert_held(&kvm->lock); 413 414 if (ulen == 0 || uaddr + ulen < uaddr) 415 return ERR_PTR(-EINVAL); 416 417 /* Calculate number of pages. */ 418 first = (uaddr & PAGE_MASK) >> PAGE_SHIFT; 419 last = ((uaddr + ulen - 1) & PAGE_MASK) >> PAGE_SHIFT; 420 npages = (last - first + 1); 421 422 locked = sev->pages_locked + npages; 423 lock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT; 424 if (locked > lock_limit && !capable(CAP_IPC_LOCK)) { 425 pr_err("SEV: %lu locked pages exceed the lock limit of %lu.\n", locked, lock_limit); 426 return ERR_PTR(-ENOMEM); 427 } 428 429 if (WARN_ON_ONCE(npages > INT_MAX)) 430 return ERR_PTR(-EINVAL); 431 432 /* Avoid using vmalloc for smaller buffers. */ 433 size = npages * sizeof(struct page *); 434 if (size > PAGE_SIZE) 435 pages = __vmalloc(size, GFP_KERNEL_ACCOUNT | __GFP_ZERO); 436 else 437 pages = kmalloc(size, GFP_KERNEL_ACCOUNT); 438 439 if (!pages) 440 return ERR_PTR(-ENOMEM); 441 442 /* Pin the user virtual address. */ 443 npinned = pin_user_pages_fast(uaddr, npages, write ? FOLL_WRITE : 0, pages); 444 if (npinned != npages) { 445 pr_err("SEV: Failure locking %lu pages.\n", npages); 446 ret = -ENOMEM; 447 goto err; 448 } 449 450 *n = npages; 451 sev->pages_locked = locked; 452 453 return pages; 454 455 err: 456 if (npinned > 0) 457 unpin_user_pages(pages, npinned); 458 459 kvfree(pages); 460 return ERR_PTR(ret); 461 } 462 463 static void sev_unpin_memory(struct kvm *kvm, struct page **pages, 464 unsigned long npages) 465 { 466 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 467 468 unpin_user_pages(pages, npages); 469 kvfree(pages); 470 sev->pages_locked -= npages; 471 } 472 473 static void sev_clflush_pages(struct page *pages[], unsigned long npages) 474 { 475 uint8_t *page_virtual; 476 unsigned long i; 477 478 if (this_cpu_has(X86_FEATURE_SME_COHERENT) || npages == 0 || 479 pages == NULL) 480 return; 481 482 for (i = 0; i < npages; i++) { 483 page_virtual = kmap_local_page(pages[i]); 484 clflush_cache_range(page_virtual, PAGE_SIZE); 485 kunmap_local(page_virtual); 486 cond_resched(); 487 } 488 } 489 490 static unsigned long get_num_contig_pages(unsigned long idx, 491 struct page **inpages, unsigned long npages) 492 { 493 unsigned long paddr, next_paddr; 494 unsigned long i = idx + 1, pages = 1; 495 496 /* find the number of contiguous pages starting from idx */ 497 paddr = __sme_page_pa(inpages[idx]); 498 while (i < npages) { 499 next_paddr = __sme_page_pa(inpages[i++]); 500 if ((paddr + PAGE_SIZE) == next_paddr) { 501 pages++; 502 paddr = next_paddr; 503 continue; 504 } 505 break; 506 } 507 508 return pages; 509 } 510 511 static int sev_launch_update_data(struct kvm *kvm, struct kvm_sev_cmd *argp) 512 { 513 unsigned long vaddr, vaddr_end, next_vaddr, npages, pages, size, i; 514 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 515 struct kvm_sev_launch_update_data params; 516 struct sev_data_launch_update_data data; 517 struct page **inpages; 518 int ret; 519 520 if (!sev_guest(kvm)) 521 return -ENOTTY; 522 523 if (copy_from_user(¶ms, (void __user *)(uintptr_t)argp->data, sizeof(params))) 524 return -EFAULT; 525 526 vaddr = params.uaddr; 527 size = params.len; 528 vaddr_end = vaddr + size; 529 530 /* Lock the user memory. */ 531 inpages = sev_pin_memory(kvm, vaddr, size, &npages, 1); 532 if (IS_ERR(inpages)) 533 return PTR_ERR(inpages); 534 535 /* 536 * Flush (on non-coherent CPUs) before LAUNCH_UPDATE encrypts pages in 537 * place; the cache may contain the data that was written unencrypted. 538 */ 539 sev_clflush_pages(inpages, npages); 540 541 data.reserved = 0; 542 data.handle = sev->handle; 543 544 for (i = 0; vaddr < vaddr_end; vaddr = next_vaddr, i += pages) { 545 int offset, len; 546 547 /* 548 * If the user buffer is not page-aligned, calculate the offset 549 * within the page. 550 */ 551 offset = vaddr & (PAGE_SIZE - 1); 552 553 /* Calculate the number of pages that can be encrypted in one go. */ 554 pages = get_num_contig_pages(i, inpages, npages); 555 556 len = min_t(size_t, ((pages * PAGE_SIZE) - offset), size); 557 558 data.len = len; 559 data.address = __sme_page_pa(inpages[i]) + offset; 560 ret = sev_issue_cmd(kvm, SEV_CMD_LAUNCH_UPDATE_DATA, &data, &argp->error); 561 if (ret) 562 goto e_unpin; 563 564 size -= len; 565 next_vaddr = vaddr + len; 566 } 567 568 e_unpin: 569 /* content of memory is updated, mark pages dirty */ 570 for (i = 0; i < npages; i++) { 571 set_page_dirty_lock(inpages[i]); 572 mark_page_accessed(inpages[i]); 573 } 574 /* unlock the user pages */ 575 sev_unpin_memory(kvm, inpages, npages); 576 return ret; 577 } 578 579 static int sev_es_sync_vmsa(struct vcpu_svm *svm) 580 { 581 struct sev_es_save_area *save = svm->sev_es.vmsa; 582 583 /* Check some debug related fields before encrypting the VMSA */ 584 if (svm->vcpu.guest_debug || (svm->vmcb->save.dr7 & ~DR7_FIXED_1)) 585 return -EINVAL; 586 587 /* 588 * SEV-ES will use a VMSA that is pointed to by the VMCB, not 589 * the traditional VMSA that is part of the VMCB. Copy the 590 * traditional VMSA as it has been built so far (in prep 591 * for LAUNCH_UPDATE_VMSA) to be the initial SEV-ES state. 592 */ 593 memcpy(save, &svm->vmcb->save, sizeof(svm->vmcb->save)); 594 595 /* Sync registgers */ 596 save->rax = svm->vcpu.arch.regs[VCPU_REGS_RAX]; 597 save->rbx = svm->vcpu.arch.regs[VCPU_REGS_RBX]; 598 save->rcx = svm->vcpu.arch.regs[VCPU_REGS_RCX]; 599 save->rdx = svm->vcpu.arch.regs[VCPU_REGS_RDX]; 600 save->rsp = svm->vcpu.arch.regs[VCPU_REGS_RSP]; 601 save->rbp = svm->vcpu.arch.regs[VCPU_REGS_RBP]; 602 save->rsi = svm->vcpu.arch.regs[VCPU_REGS_RSI]; 603 save->rdi = svm->vcpu.arch.regs[VCPU_REGS_RDI]; 604 #ifdef CONFIG_X86_64 605 save->r8 = svm->vcpu.arch.regs[VCPU_REGS_R8]; 606 save->r9 = svm->vcpu.arch.regs[VCPU_REGS_R9]; 607 save->r10 = svm->vcpu.arch.regs[VCPU_REGS_R10]; 608 save->r11 = svm->vcpu.arch.regs[VCPU_REGS_R11]; 609 save->r12 = svm->vcpu.arch.regs[VCPU_REGS_R12]; 610 save->r13 = svm->vcpu.arch.regs[VCPU_REGS_R13]; 611 save->r14 = svm->vcpu.arch.regs[VCPU_REGS_R14]; 612 save->r15 = svm->vcpu.arch.regs[VCPU_REGS_R15]; 613 #endif 614 save->rip = svm->vcpu.arch.regs[VCPU_REGS_RIP]; 615 616 /* Sync some non-GPR registers before encrypting */ 617 save->xcr0 = svm->vcpu.arch.xcr0; 618 save->pkru = svm->vcpu.arch.pkru; 619 save->xss = svm->vcpu.arch.ia32_xss; 620 save->dr6 = svm->vcpu.arch.dr6; 621 622 if (sev_es_debug_swap_enabled) { 623 save->sev_features |= SVM_SEV_FEAT_DEBUG_SWAP; 624 pr_warn_once("Enabling DebugSwap with KVM_SEV_ES_INIT. " 625 "This will not work starting with Linux 6.10\n"); 626 } 627 628 pr_debug("Virtual Machine Save Area (VMSA):\n"); 629 print_hex_dump_debug("", DUMP_PREFIX_NONE, 16, 1, save, sizeof(*save), false); 630 631 return 0; 632 } 633 634 static int __sev_launch_update_vmsa(struct kvm *kvm, struct kvm_vcpu *vcpu, 635 int *error) 636 { 637 struct sev_data_launch_update_vmsa vmsa; 638 struct vcpu_svm *svm = to_svm(vcpu); 639 int ret; 640 641 if (vcpu->guest_debug) { 642 pr_warn_once("KVM_SET_GUEST_DEBUG for SEV-ES guest is not supported"); 643 return -EINVAL; 644 } 645 646 /* Perform some pre-encryption checks against the VMSA */ 647 ret = sev_es_sync_vmsa(svm); 648 if (ret) 649 return ret; 650 651 /* 652 * The LAUNCH_UPDATE_VMSA command will perform in-place encryption of 653 * the VMSA memory content (i.e it will write the same memory region 654 * with the guest's key), so invalidate it first. 655 */ 656 clflush_cache_range(svm->sev_es.vmsa, PAGE_SIZE); 657 658 vmsa.reserved = 0; 659 vmsa.handle = to_kvm_svm(kvm)->sev_info.handle; 660 vmsa.address = __sme_pa(svm->sev_es.vmsa); 661 vmsa.len = PAGE_SIZE; 662 ret = sev_issue_cmd(kvm, SEV_CMD_LAUNCH_UPDATE_VMSA, &vmsa, error); 663 if (ret) 664 return ret; 665 666 vcpu->arch.guest_state_protected = true; 667 668 /* 669 * SEV-ES guest mandates LBR Virtualization to be _always_ ON. Enable it 670 * only after setting guest_state_protected because KVM_SET_MSRS allows 671 * dynamic toggling of LBRV (for performance reason) on write access to 672 * MSR_IA32_DEBUGCTLMSR when guest_state_protected is not set. 673 */ 674 svm_enable_lbrv(vcpu); 675 return 0; 676 } 677 678 static int sev_launch_update_vmsa(struct kvm *kvm, struct kvm_sev_cmd *argp) 679 { 680 struct kvm_vcpu *vcpu; 681 unsigned long i; 682 int ret; 683 684 if (!sev_es_guest(kvm)) 685 return -ENOTTY; 686 687 kvm_for_each_vcpu(i, vcpu, kvm) { 688 ret = mutex_lock_killable(&vcpu->mutex); 689 if (ret) 690 return ret; 691 692 ret = __sev_launch_update_vmsa(kvm, vcpu, &argp->error); 693 694 mutex_unlock(&vcpu->mutex); 695 if (ret) 696 return ret; 697 } 698 699 return 0; 700 } 701 702 static int sev_launch_measure(struct kvm *kvm, struct kvm_sev_cmd *argp) 703 { 704 void __user *measure = (void __user *)(uintptr_t)argp->data; 705 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 706 struct sev_data_launch_measure data; 707 struct kvm_sev_launch_measure params; 708 void __user *p = NULL; 709 void *blob = NULL; 710 int ret; 711 712 if (!sev_guest(kvm)) 713 return -ENOTTY; 714 715 if (copy_from_user(¶ms, measure, sizeof(params))) 716 return -EFAULT; 717 718 memset(&data, 0, sizeof(data)); 719 720 /* User wants to query the blob length */ 721 if (!params.len) 722 goto cmd; 723 724 p = (void __user *)(uintptr_t)params.uaddr; 725 if (p) { 726 if (params.len > SEV_FW_BLOB_MAX_SIZE) 727 return -EINVAL; 728 729 blob = kzalloc(params.len, GFP_KERNEL_ACCOUNT); 730 if (!blob) 731 return -ENOMEM; 732 733 data.address = __psp_pa(blob); 734 data.len = params.len; 735 } 736 737 cmd: 738 data.handle = sev->handle; 739 ret = sev_issue_cmd(kvm, SEV_CMD_LAUNCH_MEASURE, &data, &argp->error); 740 741 /* 742 * If we query the session length, FW responded with expected data. 743 */ 744 if (!params.len) 745 goto done; 746 747 if (ret) 748 goto e_free_blob; 749 750 if (blob) { 751 if (copy_to_user(p, blob, params.len)) 752 ret = -EFAULT; 753 } 754 755 done: 756 params.len = data.len; 757 if (copy_to_user(measure, ¶ms, sizeof(params))) 758 ret = -EFAULT; 759 e_free_blob: 760 kfree(blob); 761 return ret; 762 } 763 764 static int sev_launch_finish(struct kvm *kvm, struct kvm_sev_cmd *argp) 765 { 766 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 767 struct sev_data_launch_finish data; 768 769 if (!sev_guest(kvm)) 770 return -ENOTTY; 771 772 data.handle = sev->handle; 773 return sev_issue_cmd(kvm, SEV_CMD_LAUNCH_FINISH, &data, &argp->error); 774 } 775 776 static int sev_guest_status(struct kvm *kvm, struct kvm_sev_cmd *argp) 777 { 778 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 779 struct kvm_sev_guest_status params; 780 struct sev_data_guest_status data; 781 int ret; 782 783 if (!sev_guest(kvm)) 784 return -ENOTTY; 785 786 memset(&data, 0, sizeof(data)); 787 788 data.handle = sev->handle; 789 ret = sev_issue_cmd(kvm, SEV_CMD_GUEST_STATUS, &data, &argp->error); 790 if (ret) 791 return ret; 792 793 params.policy = data.policy; 794 params.state = data.state; 795 params.handle = data.handle; 796 797 if (copy_to_user((void __user *)(uintptr_t)argp->data, ¶ms, sizeof(params))) 798 ret = -EFAULT; 799 800 return ret; 801 } 802 803 static int __sev_issue_dbg_cmd(struct kvm *kvm, unsigned long src, 804 unsigned long dst, int size, 805 int *error, bool enc) 806 { 807 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 808 struct sev_data_dbg data; 809 810 data.reserved = 0; 811 data.handle = sev->handle; 812 data.dst_addr = dst; 813 data.src_addr = src; 814 data.len = size; 815 816 return sev_issue_cmd(kvm, 817 enc ? SEV_CMD_DBG_ENCRYPT : SEV_CMD_DBG_DECRYPT, 818 &data, error); 819 } 820 821 static int __sev_dbg_decrypt(struct kvm *kvm, unsigned long src_paddr, 822 unsigned long dst_paddr, int sz, int *err) 823 { 824 int offset; 825 826 /* 827 * Its safe to read more than we are asked, caller should ensure that 828 * destination has enough space. 829 */ 830 offset = src_paddr & 15; 831 src_paddr = round_down(src_paddr, 16); 832 sz = round_up(sz + offset, 16); 833 834 return __sev_issue_dbg_cmd(kvm, src_paddr, dst_paddr, sz, err, false); 835 } 836 837 static int __sev_dbg_decrypt_user(struct kvm *kvm, unsigned long paddr, 838 void __user *dst_uaddr, 839 unsigned long dst_paddr, 840 int size, int *err) 841 { 842 struct page *tpage = NULL; 843 int ret, offset; 844 845 /* if inputs are not 16-byte then use intermediate buffer */ 846 if (!IS_ALIGNED(dst_paddr, 16) || 847 !IS_ALIGNED(paddr, 16) || 848 !IS_ALIGNED(size, 16)) { 849 tpage = (void *)alloc_page(GFP_KERNEL_ACCOUNT | __GFP_ZERO); 850 if (!tpage) 851 return -ENOMEM; 852 853 dst_paddr = __sme_page_pa(tpage); 854 } 855 856 ret = __sev_dbg_decrypt(kvm, paddr, dst_paddr, size, err); 857 if (ret) 858 goto e_free; 859 860 if (tpage) { 861 offset = paddr & 15; 862 if (copy_to_user(dst_uaddr, page_address(tpage) + offset, size)) 863 ret = -EFAULT; 864 } 865 866 e_free: 867 if (tpage) 868 __free_page(tpage); 869 870 return ret; 871 } 872 873 static int __sev_dbg_encrypt_user(struct kvm *kvm, unsigned long paddr, 874 void __user *vaddr, 875 unsigned long dst_paddr, 876 void __user *dst_vaddr, 877 int size, int *error) 878 { 879 struct page *src_tpage = NULL; 880 struct page *dst_tpage = NULL; 881 int ret, len = size; 882 883 /* If source buffer is not aligned then use an intermediate buffer */ 884 if (!IS_ALIGNED((unsigned long)vaddr, 16)) { 885 src_tpage = alloc_page(GFP_KERNEL_ACCOUNT); 886 if (!src_tpage) 887 return -ENOMEM; 888 889 if (copy_from_user(page_address(src_tpage), vaddr, size)) { 890 __free_page(src_tpage); 891 return -EFAULT; 892 } 893 894 paddr = __sme_page_pa(src_tpage); 895 } 896 897 /* 898 * If destination buffer or length is not aligned then do read-modify-write: 899 * - decrypt destination in an intermediate buffer 900 * - copy the source buffer in an intermediate buffer 901 * - use the intermediate buffer as source buffer 902 */ 903 if (!IS_ALIGNED((unsigned long)dst_vaddr, 16) || !IS_ALIGNED(size, 16)) { 904 int dst_offset; 905 906 dst_tpage = alloc_page(GFP_KERNEL_ACCOUNT); 907 if (!dst_tpage) { 908 ret = -ENOMEM; 909 goto e_free; 910 } 911 912 ret = __sev_dbg_decrypt(kvm, dst_paddr, 913 __sme_page_pa(dst_tpage), size, error); 914 if (ret) 915 goto e_free; 916 917 /* 918 * If source is kernel buffer then use memcpy() otherwise 919 * copy_from_user(). 920 */ 921 dst_offset = dst_paddr & 15; 922 923 if (src_tpage) 924 memcpy(page_address(dst_tpage) + dst_offset, 925 page_address(src_tpage), size); 926 else { 927 if (copy_from_user(page_address(dst_tpage) + dst_offset, 928 vaddr, size)) { 929 ret = -EFAULT; 930 goto e_free; 931 } 932 } 933 934 paddr = __sme_page_pa(dst_tpage); 935 dst_paddr = round_down(dst_paddr, 16); 936 len = round_up(size, 16); 937 } 938 939 ret = __sev_issue_dbg_cmd(kvm, paddr, dst_paddr, len, error, true); 940 941 e_free: 942 if (src_tpage) 943 __free_page(src_tpage); 944 if (dst_tpage) 945 __free_page(dst_tpage); 946 return ret; 947 } 948 949 static int sev_dbg_crypt(struct kvm *kvm, struct kvm_sev_cmd *argp, bool dec) 950 { 951 unsigned long vaddr, vaddr_end, next_vaddr; 952 unsigned long dst_vaddr; 953 struct page **src_p, **dst_p; 954 struct kvm_sev_dbg debug; 955 unsigned long n; 956 unsigned int size; 957 int ret; 958 959 if (!sev_guest(kvm)) 960 return -ENOTTY; 961 962 if (copy_from_user(&debug, (void __user *)(uintptr_t)argp->data, sizeof(debug))) 963 return -EFAULT; 964 965 if (!debug.len || debug.src_uaddr + debug.len < debug.src_uaddr) 966 return -EINVAL; 967 if (!debug.dst_uaddr) 968 return -EINVAL; 969 970 vaddr = debug.src_uaddr; 971 size = debug.len; 972 vaddr_end = vaddr + size; 973 dst_vaddr = debug.dst_uaddr; 974 975 for (; vaddr < vaddr_end; vaddr = next_vaddr) { 976 int len, s_off, d_off; 977 978 /* lock userspace source and destination page */ 979 src_p = sev_pin_memory(kvm, vaddr & PAGE_MASK, PAGE_SIZE, &n, 0); 980 if (IS_ERR(src_p)) 981 return PTR_ERR(src_p); 982 983 dst_p = sev_pin_memory(kvm, dst_vaddr & PAGE_MASK, PAGE_SIZE, &n, 1); 984 if (IS_ERR(dst_p)) { 985 sev_unpin_memory(kvm, src_p, n); 986 return PTR_ERR(dst_p); 987 } 988 989 /* 990 * Flush (on non-coherent CPUs) before DBG_{DE,EN}CRYPT read or modify 991 * the pages; flush the destination too so that future accesses do not 992 * see stale data. 993 */ 994 sev_clflush_pages(src_p, 1); 995 sev_clflush_pages(dst_p, 1); 996 997 /* 998 * Since user buffer may not be page aligned, calculate the 999 * offset within the page. 1000 */ 1001 s_off = vaddr & ~PAGE_MASK; 1002 d_off = dst_vaddr & ~PAGE_MASK; 1003 len = min_t(size_t, (PAGE_SIZE - s_off), size); 1004 1005 if (dec) 1006 ret = __sev_dbg_decrypt_user(kvm, 1007 __sme_page_pa(src_p[0]) + s_off, 1008 (void __user *)dst_vaddr, 1009 __sme_page_pa(dst_p[0]) + d_off, 1010 len, &argp->error); 1011 else 1012 ret = __sev_dbg_encrypt_user(kvm, 1013 __sme_page_pa(src_p[0]) + s_off, 1014 (void __user *)vaddr, 1015 __sme_page_pa(dst_p[0]) + d_off, 1016 (void __user *)dst_vaddr, 1017 len, &argp->error); 1018 1019 sev_unpin_memory(kvm, src_p, n); 1020 sev_unpin_memory(kvm, dst_p, n); 1021 1022 if (ret) 1023 goto err; 1024 1025 next_vaddr = vaddr + len; 1026 dst_vaddr = dst_vaddr + len; 1027 size -= len; 1028 } 1029 err: 1030 return ret; 1031 } 1032 1033 static int sev_launch_secret(struct kvm *kvm, struct kvm_sev_cmd *argp) 1034 { 1035 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 1036 struct sev_data_launch_secret data; 1037 struct kvm_sev_launch_secret params; 1038 struct page **pages; 1039 void *blob, *hdr; 1040 unsigned long n, i; 1041 int ret, offset; 1042 1043 if (!sev_guest(kvm)) 1044 return -ENOTTY; 1045 1046 if (copy_from_user(¶ms, (void __user *)(uintptr_t)argp->data, sizeof(params))) 1047 return -EFAULT; 1048 1049 pages = sev_pin_memory(kvm, params.guest_uaddr, params.guest_len, &n, 1); 1050 if (IS_ERR(pages)) 1051 return PTR_ERR(pages); 1052 1053 /* 1054 * Flush (on non-coherent CPUs) before LAUNCH_SECRET encrypts pages in 1055 * place; the cache may contain the data that was written unencrypted. 1056 */ 1057 sev_clflush_pages(pages, n); 1058 1059 /* 1060 * The secret must be copied into contiguous memory region, lets verify 1061 * that userspace memory pages are contiguous before we issue command. 1062 */ 1063 if (get_num_contig_pages(0, pages, n) != n) { 1064 ret = -EINVAL; 1065 goto e_unpin_memory; 1066 } 1067 1068 memset(&data, 0, sizeof(data)); 1069 1070 offset = params.guest_uaddr & (PAGE_SIZE - 1); 1071 data.guest_address = __sme_page_pa(pages[0]) + offset; 1072 data.guest_len = params.guest_len; 1073 1074 blob = psp_copy_user_blob(params.trans_uaddr, params.trans_len); 1075 if (IS_ERR(blob)) { 1076 ret = PTR_ERR(blob); 1077 goto e_unpin_memory; 1078 } 1079 1080 data.trans_address = __psp_pa(blob); 1081 data.trans_len = params.trans_len; 1082 1083 hdr = psp_copy_user_blob(params.hdr_uaddr, params.hdr_len); 1084 if (IS_ERR(hdr)) { 1085 ret = PTR_ERR(hdr); 1086 goto e_free_blob; 1087 } 1088 data.hdr_address = __psp_pa(hdr); 1089 data.hdr_len = params.hdr_len; 1090 1091 data.handle = sev->handle; 1092 ret = sev_issue_cmd(kvm, SEV_CMD_LAUNCH_UPDATE_SECRET, &data, &argp->error); 1093 1094 kfree(hdr); 1095 1096 e_free_blob: 1097 kfree(blob); 1098 e_unpin_memory: 1099 /* content of memory is updated, mark pages dirty */ 1100 for (i = 0; i < n; i++) { 1101 set_page_dirty_lock(pages[i]); 1102 mark_page_accessed(pages[i]); 1103 } 1104 sev_unpin_memory(kvm, pages, n); 1105 return ret; 1106 } 1107 1108 static int sev_get_attestation_report(struct kvm *kvm, struct kvm_sev_cmd *argp) 1109 { 1110 void __user *report = (void __user *)(uintptr_t)argp->data; 1111 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 1112 struct sev_data_attestation_report data; 1113 struct kvm_sev_attestation_report params; 1114 void __user *p; 1115 void *blob = NULL; 1116 int ret; 1117 1118 if (!sev_guest(kvm)) 1119 return -ENOTTY; 1120 1121 if (copy_from_user(¶ms, (void __user *)(uintptr_t)argp->data, sizeof(params))) 1122 return -EFAULT; 1123 1124 memset(&data, 0, sizeof(data)); 1125 1126 /* User wants to query the blob length */ 1127 if (!params.len) 1128 goto cmd; 1129 1130 p = (void __user *)(uintptr_t)params.uaddr; 1131 if (p) { 1132 if (params.len > SEV_FW_BLOB_MAX_SIZE) 1133 return -EINVAL; 1134 1135 blob = kzalloc(params.len, GFP_KERNEL_ACCOUNT); 1136 if (!blob) 1137 return -ENOMEM; 1138 1139 data.address = __psp_pa(blob); 1140 data.len = params.len; 1141 memcpy(data.mnonce, params.mnonce, sizeof(params.mnonce)); 1142 } 1143 cmd: 1144 data.handle = sev->handle; 1145 ret = sev_issue_cmd(kvm, SEV_CMD_ATTESTATION_REPORT, &data, &argp->error); 1146 /* 1147 * If we query the session length, FW responded with expected data. 1148 */ 1149 if (!params.len) 1150 goto done; 1151 1152 if (ret) 1153 goto e_free_blob; 1154 1155 if (blob) { 1156 if (copy_to_user(p, blob, params.len)) 1157 ret = -EFAULT; 1158 } 1159 1160 done: 1161 params.len = data.len; 1162 if (copy_to_user(report, ¶ms, sizeof(params))) 1163 ret = -EFAULT; 1164 e_free_blob: 1165 kfree(blob); 1166 return ret; 1167 } 1168 1169 /* Userspace wants to query session length. */ 1170 static int 1171 __sev_send_start_query_session_length(struct kvm *kvm, struct kvm_sev_cmd *argp, 1172 struct kvm_sev_send_start *params) 1173 { 1174 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 1175 struct sev_data_send_start data; 1176 int ret; 1177 1178 memset(&data, 0, sizeof(data)); 1179 data.handle = sev->handle; 1180 ret = sev_issue_cmd(kvm, SEV_CMD_SEND_START, &data, &argp->error); 1181 1182 params->session_len = data.session_len; 1183 if (copy_to_user((void __user *)(uintptr_t)argp->data, params, 1184 sizeof(struct kvm_sev_send_start))) 1185 ret = -EFAULT; 1186 1187 return ret; 1188 } 1189 1190 static int sev_send_start(struct kvm *kvm, struct kvm_sev_cmd *argp) 1191 { 1192 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 1193 struct sev_data_send_start data; 1194 struct kvm_sev_send_start params; 1195 void *amd_certs, *session_data; 1196 void *pdh_cert, *plat_certs; 1197 int ret; 1198 1199 if (!sev_guest(kvm)) 1200 return -ENOTTY; 1201 1202 if (copy_from_user(¶ms, (void __user *)(uintptr_t)argp->data, 1203 sizeof(struct kvm_sev_send_start))) 1204 return -EFAULT; 1205 1206 /* if session_len is zero, userspace wants to query the session length */ 1207 if (!params.session_len) 1208 return __sev_send_start_query_session_length(kvm, argp, 1209 ¶ms); 1210 1211 /* some sanity checks */ 1212 if (!params.pdh_cert_uaddr || !params.pdh_cert_len || 1213 !params.session_uaddr || params.session_len > SEV_FW_BLOB_MAX_SIZE) 1214 return -EINVAL; 1215 1216 /* allocate the memory to hold the session data blob */ 1217 session_data = kzalloc(params.session_len, GFP_KERNEL_ACCOUNT); 1218 if (!session_data) 1219 return -ENOMEM; 1220 1221 /* copy the certificate blobs from userspace */ 1222 pdh_cert = psp_copy_user_blob(params.pdh_cert_uaddr, 1223 params.pdh_cert_len); 1224 if (IS_ERR(pdh_cert)) { 1225 ret = PTR_ERR(pdh_cert); 1226 goto e_free_session; 1227 } 1228 1229 plat_certs = psp_copy_user_blob(params.plat_certs_uaddr, 1230 params.plat_certs_len); 1231 if (IS_ERR(plat_certs)) { 1232 ret = PTR_ERR(plat_certs); 1233 goto e_free_pdh; 1234 } 1235 1236 amd_certs = psp_copy_user_blob(params.amd_certs_uaddr, 1237 params.amd_certs_len); 1238 if (IS_ERR(amd_certs)) { 1239 ret = PTR_ERR(amd_certs); 1240 goto e_free_plat_cert; 1241 } 1242 1243 /* populate the FW SEND_START field with system physical address */ 1244 memset(&data, 0, sizeof(data)); 1245 data.pdh_cert_address = __psp_pa(pdh_cert); 1246 data.pdh_cert_len = params.pdh_cert_len; 1247 data.plat_certs_address = __psp_pa(plat_certs); 1248 data.plat_certs_len = params.plat_certs_len; 1249 data.amd_certs_address = __psp_pa(amd_certs); 1250 data.amd_certs_len = params.amd_certs_len; 1251 data.session_address = __psp_pa(session_data); 1252 data.session_len = params.session_len; 1253 data.handle = sev->handle; 1254 1255 ret = sev_issue_cmd(kvm, SEV_CMD_SEND_START, &data, &argp->error); 1256 1257 if (!ret && copy_to_user((void __user *)(uintptr_t)params.session_uaddr, 1258 session_data, params.session_len)) { 1259 ret = -EFAULT; 1260 goto e_free_amd_cert; 1261 } 1262 1263 params.policy = data.policy; 1264 params.session_len = data.session_len; 1265 if (copy_to_user((void __user *)(uintptr_t)argp->data, ¶ms, 1266 sizeof(struct kvm_sev_send_start))) 1267 ret = -EFAULT; 1268 1269 e_free_amd_cert: 1270 kfree(amd_certs); 1271 e_free_plat_cert: 1272 kfree(plat_certs); 1273 e_free_pdh: 1274 kfree(pdh_cert); 1275 e_free_session: 1276 kfree(session_data); 1277 return ret; 1278 } 1279 1280 /* Userspace wants to query either header or trans length. */ 1281 static int 1282 __sev_send_update_data_query_lengths(struct kvm *kvm, struct kvm_sev_cmd *argp, 1283 struct kvm_sev_send_update_data *params) 1284 { 1285 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 1286 struct sev_data_send_update_data data; 1287 int ret; 1288 1289 memset(&data, 0, sizeof(data)); 1290 data.handle = sev->handle; 1291 ret = sev_issue_cmd(kvm, SEV_CMD_SEND_UPDATE_DATA, &data, &argp->error); 1292 1293 params->hdr_len = data.hdr_len; 1294 params->trans_len = data.trans_len; 1295 1296 if (copy_to_user((void __user *)(uintptr_t)argp->data, params, 1297 sizeof(struct kvm_sev_send_update_data))) 1298 ret = -EFAULT; 1299 1300 return ret; 1301 } 1302 1303 static int sev_send_update_data(struct kvm *kvm, struct kvm_sev_cmd *argp) 1304 { 1305 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 1306 struct sev_data_send_update_data data; 1307 struct kvm_sev_send_update_data params; 1308 void *hdr, *trans_data; 1309 struct page **guest_page; 1310 unsigned long n; 1311 int ret, offset; 1312 1313 if (!sev_guest(kvm)) 1314 return -ENOTTY; 1315 1316 if (copy_from_user(¶ms, (void __user *)(uintptr_t)argp->data, 1317 sizeof(struct kvm_sev_send_update_data))) 1318 return -EFAULT; 1319 1320 /* userspace wants to query either header or trans length */ 1321 if (!params.trans_len || !params.hdr_len) 1322 return __sev_send_update_data_query_lengths(kvm, argp, ¶ms); 1323 1324 if (!params.trans_uaddr || !params.guest_uaddr || 1325 !params.guest_len || !params.hdr_uaddr) 1326 return -EINVAL; 1327 1328 /* Check if we are crossing the page boundary */ 1329 offset = params.guest_uaddr & (PAGE_SIZE - 1); 1330 if (params.guest_len > PAGE_SIZE || (params.guest_len + offset) > PAGE_SIZE) 1331 return -EINVAL; 1332 1333 /* Pin guest memory */ 1334 guest_page = sev_pin_memory(kvm, params.guest_uaddr & PAGE_MASK, 1335 PAGE_SIZE, &n, 0); 1336 if (IS_ERR(guest_page)) 1337 return PTR_ERR(guest_page); 1338 1339 /* allocate memory for header and transport buffer */ 1340 ret = -ENOMEM; 1341 hdr = kzalloc(params.hdr_len, GFP_KERNEL_ACCOUNT); 1342 if (!hdr) 1343 goto e_unpin; 1344 1345 trans_data = kzalloc(params.trans_len, GFP_KERNEL_ACCOUNT); 1346 if (!trans_data) 1347 goto e_free_hdr; 1348 1349 memset(&data, 0, sizeof(data)); 1350 data.hdr_address = __psp_pa(hdr); 1351 data.hdr_len = params.hdr_len; 1352 data.trans_address = __psp_pa(trans_data); 1353 data.trans_len = params.trans_len; 1354 1355 /* The SEND_UPDATE_DATA command requires C-bit to be always set. */ 1356 data.guest_address = (page_to_pfn(guest_page[0]) << PAGE_SHIFT) + offset; 1357 data.guest_address |= sev_me_mask; 1358 data.guest_len = params.guest_len; 1359 data.handle = sev->handle; 1360 1361 ret = sev_issue_cmd(kvm, SEV_CMD_SEND_UPDATE_DATA, &data, &argp->error); 1362 1363 if (ret) 1364 goto e_free_trans_data; 1365 1366 /* copy transport buffer to user space */ 1367 if (copy_to_user((void __user *)(uintptr_t)params.trans_uaddr, 1368 trans_data, params.trans_len)) { 1369 ret = -EFAULT; 1370 goto e_free_trans_data; 1371 } 1372 1373 /* Copy packet header to userspace. */ 1374 if (copy_to_user((void __user *)(uintptr_t)params.hdr_uaddr, hdr, 1375 params.hdr_len)) 1376 ret = -EFAULT; 1377 1378 e_free_trans_data: 1379 kfree(trans_data); 1380 e_free_hdr: 1381 kfree(hdr); 1382 e_unpin: 1383 sev_unpin_memory(kvm, guest_page, n); 1384 1385 return ret; 1386 } 1387 1388 static int sev_send_finish(struct kvm *kvm, struct kvm_sev_cmd *argp) 1389 { 1390 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 1391 struct sev_data_send_finish data; 1392 1393 if (!sev_guest(kvm)) 1394 return -ENOTTY; 1395 1396 data.handle = sev->handle; 1397 return sev_issue_cmd(kvm, SEV_CMD_SEND_FINISH, &data, &argp->error); 1398 } 1399 1400 static int sev_send_cancel(struct kvm *kvm, struct kvm_sev_cmd *argp) 1401 { 1402 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 1403 struct sev_data_send_cancel data; 1404 1405 if (!sev_guest(kvm)) 1406 return -ENOTTY; 1407 1408 data.handle = sev->handle; 1409 return sev_issue_cmd(kvm, SEV_CMD_SEND_CANCEL, &data, &argp->error); 1410 } 1411 1412 static int sev_receive_start(struct kvm *kvm, struct kvm_sev_cmd *argp) 1413 { 1414 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 1415 struct sev_data_receive_start start; 1416 struct kvm_sev_receive_start params; 1417 int *error = &argp->error; 1418 void *session_data; 1419 void *pdh_data; 1420 int ret; 1421 1422 if (!sev_guest(kvm)) 1423 return -ENOTTY; 1424 1425 /* Get parameter from the userspace */ 1426 if (copy_from_user(¶ms, (void __user *)(uintptr_t)argp->data, 1427 sizeof(struct kvm_sev_receive_start))) 1428 return -EFAULT; 1429 1430 /* some sanity checks */ 1431 if (!params.pdh_uaddr || !params.pdh_len || 1432 !params.session_uaddr || !params.session_len) 1433 return -EINVAL; 1434 1435 pdh_data = psp_copy_user_blob(params.pdh_uaddr, params.pdh_len); 1436 if (IS_ERR(pdh_data)) 1437 return PTR_ERR(pdh_data); 1438 1439 session_data = psp_copy_user_blob(params.session_uaddr, 1440 params.session_len); 1441 if (IS_ERR(session_data)) { 1442 ret = PTR_ERR(session_data); 1443 goto e_free_pdh; 1444 } 1445 1446 memset(&start, 0, sizeof(start)); 1447 start.handle = params.handle; 1448 start.policy = params.policy; 1449 start.pdh_cert_address = __psp_pa(pdh_data); 1450 start.pdh_cert_len = params.pdh_len; 1451 start.session_address = __psp_pa(session_data); 1452 start.session_len = params.session_len; 1453 1454 /* create memory encryption context */ 1455 ret = __sev_issue_cmd(argp->sev_fd, SEV_CMD_RECEIVE_START, &start, 1456 error); 1457 if (ret) 1458 goto e_free_session; 1459 1460 /* Bind ASID to this guest */ 1461 ret = sev_bind_asid(kvm, start.handle, error); 1462 if (ret) { 1463 sev_decommission(start.handle); 1464 goto e_free_session; 1465 } 1466 1467 params.handle = start.handle; 1468 if (copy_to_user((void __user *)(uintptr_t)argp->data, 1469 ¶ms, sizeof(struct kvm_sev_receive_start))) { 1470 ret = -EFAULT; 1471 sev_unbind_asid(kvm, start.handle); 1472 goto e_free_session; 1473 } 1474 1475 sev->handle = start.handle; 1476 sev->fd = argp->sev_fd; 1477 1478 e_free_session: 1479 kfree(session_data); 1480 e_free_pdh: 1481 kfree(pdh_data); 1482 1483 return ret; 1484 } 1485 1486 static int sev_receive_update_data(struct kvm *kvm, struct kvm_sev_cmd *argp) 1487 { 1488 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 1489 struct kvm_sev_receive_update_data params; 1490 struct sev_data_receive_update_data data; 1491 void *hdr = NULL, *trans = NULL; 1492 struct page **guest_page; 1493 unsigned long n; 1494 int ret, offset; 1495 1496 if (!sev_guest(kvm)) 1497 return -EINVAL; 1498 1499 if (copy_from_user(¶ms, (void __user *)(uintptr_t)argp->data, 1500 sizeof(struct kvm_sev_receive_update_data))) 1501 return -EFAULT; 1502 1503 if (!params.hdr_uaddr || !params.hdr_len || 1504 !params.guest_uaddr || !params.guest_len || 1505 !params.trans_uaddr || !params.trans_len) 1506 return -EINVAL; 1507 1508 /* Check if we are crossing the page boundary */ 1509 offset = params.guest_uaddr & (PAGE_SIZE - 1); 1510 if (params.guest_len > PAGE_SIZE || (params.guest_len + offset) > PAGE_SIZE) 1511 return -EINVAL; 1512 1513 hdr = psp_copy_user_blob(params.hdr_uaddr, params.hdr_len); 1514 if (IS_ERR(hdr)) 1515 return PTR_ERR(hdr); 1516 1517 trans = psp_copy_user_blob(params.trans_uaddr, params.trans_len); 1518 if (IS_ERR(trans)) { 1519 ret = PTR_ERR(trans); 1520 goto e_free_hdr; 1521 } 1522 1523 memset(&data, 0, sizeof(data)); 1524 data.hdr_address = __psp_pa(hdr); 1525 data.hdr_len = params.hdr_len; 1526 data.trans_address = __psp_pa(trans); 1527 data.trans_len = params.trans_len; 1528 1529 /* Pin guest memory */ 1530 guest_page = sev_pin_memory(kvm, params.guest_uaddr & PAGE_MASK, 1531 PAGE_SIZE, &n, 1); 1532 if (IS_ERR(guest_page)) { 1533 ret = PTR_ERR(guest_page); 1534 goto e_free_trans; 1535 } 1536 1537 /* 1538 * Flush (on non-coherent CPUs) before RECEIVE_UPDATE_DATA, the PSP 1539 * encrypts the written data with the guest's key, and the cache may 1540 * contain dirty, unencrypted data. 1541 */ 1542 sev_clflush_pages(guest_page, n); 1543 1544 /* The RECEIVE_UPDATE_DATA command requires C-bit to be always set. */ 1545 data.guest_address = (page_to_pfn(guest_page[0]) << PAGE_SHIFT) + offset; 1546 data.guest_address |= sev_me_mask; 1547 data.guest_len = params.guest_len; 1548 data.handle = sev->handle; 1549 1550 ret = sev_issue_cmd(kvm, SEV_CMD_RECEIVE_UPDATE_DATA, &data, 1551 &argp->error); 1552 1553 sev_unpin_memory(kvm, guest_page, n); 1554 1555 e_free_trans: 1556 kfree(trans); 1557 e_free_hdr: 1558 kfree(hdr); 1559 1560 return ret; 1561 } 1562 1563 static int sev_receive_finish(struct kvm *kvm, struct kvm_sev_cmd *argp) 1564 { 1565 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 1566 struct sev_data_receive_finish data; 1567 1568 if (!sev_guest(kvm)) 1569 return -ENOTTY; 1570 1571 data.handle = sev->handle; 1572 return sev_issue_cmd(kvm, SEV_CMD_RECEIVE_FINISH, &data, &argp->error); 1573 } 1574 1575 static bool is_cmd_allowed_from_mirror(u32 cmd_id) 1576 { 1577 /* 1578 * Allow mirrors VM to call KVM_SEV_LAUNCH_UPDATE_VMSA to enable SEV-ES 1579 * active mirror VMs. Also allow the debugging and status commands. 1580 */ 1581 if (cmd_id == KVM_SEV_LAUNCH_UPDATE_VMSA || 1582 cmd_id == KVM_SEV_GUEST_STATUS || cmd_id == KVM_SEV_DBG_DECRYPT || 1583 cmd_id == KVM_SEV_DBG_ENCRYPT) 1584 return true; 1585 1586 return false; 1587 } 1588 1589 static int sev_lock_two_vms(struct kvm *dst_kvm, struct kvm *src_kvm) 1590 { 1591 struct kvm_sev_info *dst_sev = &to_kvm_svm(dst_kvm)->sev_info; 1592 struct kvm_sev_info *src_sev = &to_kvm_svm(src_kvm)->sev_info; 1593 int r = -EBUSY; 1594 1595 if (dst_kvm == src_kvm) 1596 return -EINVAL; 1597 1598 /* 1599 * Bail if these VMs are already involved in a migration to avoid 1600 * deadlock between two VMs trying to migrate to/from each other. 1601 */ 1602 if (atomic_cmpxchg_acquire(&dst_sev->migration_in_progress, 0, 1)) 1603 return -EBUSY; 1604 1605 if (atomic_cmpxchg_acquire(&src_sev->migration_in_progress, 0, 1)) 1606 goto release_dst; 1607 1608 r = -EINTR; 1609 if (mutex_lock_killable(&dst_kvm->lock)) 1610 goto release_src; 1611 if (mutex_lock_killable_nested(&src_kvm->lock, SINGLE_DEPTH_NESTING)) 1612 goto unlock_dst; 1613 return 0; 1614 1615 unlock_dst: 1616 mutex_unlock(&dst_kvm->lock); 1617 release_src: 1618 atomic_set_release(&src_sev->migration_in_progress, 0); 1619 release_dst: 1620 atomic_set_release(&dst_sev->migration_in_progress, 0); 1621 return r; 1622 } 1623 1624 static void sev_unlock_two_vms(struct kvm *dst_kvm, struct kvm *src_kvm) 1625 { 1626 struct kvm_sev_info *dst_sev = &to_kvm_svm(dst_kvm)->sev_info; 1627 struct kvm_sev_info *src_sev = &to_kvm_svm(src_kvm)->sev_info; 1628 1629 mutex_unlock(&dst_kvm->lock); 1630 mutex_unlock(&src_kvm->lock); 1631 atomic_set_release(&dst_sev->migration_in_progress, 0); 1632 atomic_set_release(&src_sev->migration_in_progress, 0); 1633 } 1634 1635 /* vCPU mutex subclasses. */ 1636 enum sev_migration_role { 1637 SEV_MIGRATION_SOURCE = 0, 1638 SEV_MIGRATION_TARGET, 1639 SEV_NR_MIGRATION_ROLES, 1640 }; 1641 1642 static int sev_lock_vcpus_for_migration(struct kvm *kvm, 1643 enum sev_migration_role role) 1644 { 1645 struct kvm_vcpu *vcpu; 1646 unsigned long i, j; 1647 1648 kvm_for_each_vcpu(i, vcpu, kvm) { 1649 if (mutex_lock_killable_nested(&vcpu->mutex, role)) 1650 goto out_unlock; 1651 1652 #ifdef CONFIG_PROVE_LOCKING 1653 if (!i) 1654 /* 1655 * Reset the role to one that avoids colliding with 1656 * the role used for the first vcpu mutex. 1657 */ 1658 role = SEV_NR_MIGRATION_ROLES; 1659 else 1660 mutex_release(&vcpu->mutex.dep_map, _THIS_IP_); 1661 #endif 1662 } 1663 1664 return 0; 1665 1666 out_unlock: 1667 1668 kvm_for_each_vcpu(j, vcpu, kvm) { 1669 if (i == j) 1670 break; 1671 1672 #ifdef CONFIG_PROVE_LOCKING 1673 if (j) 1674 mutex_acquire(&vcpu->mutex.dep_map, role, 0, _THIS_IP_); 1675 #endif 1676 1677 mutex_unlock(&vcpu->mutex); 1678 } 1679 return -EINTR; 1680 } 1681 1682 static void sev_unlock_vcpus_for_migration(struct kvm *kvm) 1683 { 1684 struct kvm_vcpu *vcpu; 1685 unsigned long i; 1686 bool first = true; 1687 1688 kvm_for_each_vcpu(i, vcpu, kvm) { 1689 if (first) 1690 first = false; 1691 else 1692 mutex_acquire(&vcpu->mutex.dep_map, 1693 SEV_NR_MIGRATION_ROLES, 0, _THIS_IP_); 1694 1695 mutex_unlock(&vcpu->mutex); 1696 } 1697 } 1698 1699 static void sev_migrate_from(struct kvm *dst_kvm, struct kvm *src_kvm) 1700 { 1701 struct kvm_sev_info *dst = &to_kvm_svm(dst_kvm)->sev_info; 1702 struct kvm_sev_info *src = &to_kvm_svm(src_kvm)->sev_info; 1703 struct kvm_vcpu *dst_vcpu, *src_vcpu; 1704 struct vcpu_svm *dst_svm, *src_svm; 1705 struct kvm_sev_info *mirror; 1706 unsigned long i; 1707 1708 dst->active = true; 1709 dst->asid = src->asid; 1710 dst->handle = src->handle; 1711 dst->pages_locked = src->pages_locked; 1712 dst->enc_context_owner = src->enc_context_owner; 1713 dst->es_active = src->es_active; 1714 1715 src->asid = 0; 1716 src->active = false; 1717 src->handle = 0; 1718 src->pages_locked = 0; 1719 src->enc_context_owner = NULL; 1720 src->es_active = false; 1721 1722 list_cut_before(&dst->regions_list, &src->regions_list, &src->regions_list); 1723 1724 /* 1725 * If this VM has mirrors, "transfer" each mirror's refcount of the 1726 * source to the destination (this KVM). The caller holds a reference 1727 * to the source, so there's no danger of use-after-free. 1728 */ 1729 list_cut_before(&dst->mirror_vms, &src->mirror_vms, &src->mirror_vms); 1730 list_for_each_entry(mirror, &dst->mirror_vms, mirror_entry) { 1731 kvm_get_kvm(dst_kvm); 1732 kvm_put_kvm(src_kvm); 1733 mirror->enc_context_owner = dst_kvm; 1734 } 1735 1736 /* 1737 * If this VM is a mirror, remove the old mirror from the owners list 1738 * and add the new mirror to the list. 1739 */ 1740 if (is_mirroring_enc_context(dst_kvm)) { 1741 struct kvm_sev_info *owner_sev_info = 1742 &to_kvm_svm(dst->enc_context_owner)->sev_info; 1743 1744 list_del(&src->mirror_entry); 1745 list_add_tail(&dst->mirror_entry, &owner_sev_info->mirror_vms); 1746 } 1747 1748 kvm_for_each_vcpu(i, dst_vcpu, dst_kvm) { 1749 dst_svm = to_svm(dst_vcpu); 1750 1751 sev_init_vmcb(dst_svm); 1752 1753 if (!dst->es_active) 1754 continue; 1755 1756 /* 1757 * Note, the source is not required to have the same number of 1758 * vCPUs as the destination when migrating a vanilla SEV VM. 1759 */ 1760 src_vcpu = kvm_get_vcpu(src_kvm, i); 1761 src_svm = to_svm(src_vcpu); 1762 1763 /* 1764 * Transfer VMSA and GHCB state to the destination. Nullify and 1765 * clear source fields as appropriate, the state now belongs to 1766 * the destination. 1767 */ 1768 memcpy(&dst_svm->sev_es, &src_svm->sev_es, sizeof(src_svm->sev_es)); 1769 dst_svm->vmcb->control.ghcb_gpa = src_svm->vmcb->control.ghcb_gpa; 1770 dst_svm->vmcb->control.vmsa_pa = src_svm->vmcb->control.vmsa_pa; 1771 dst_vcpu->arch.guest_state_protected = true; 1772 1773 memset(&src_svm->sev_es, 0, sizeof(src_svm->sev_es)); 1774 src_svm->vmcb->control.ghcb_gpa = INVALID_PAGE; 1775 src_svm->vmcb->control.vmsa_pa = INVALID_PAGE; 1776 src_vcpu->arch.guest_state_protected = false; 1777 } 1778 } 1779 1780 static int sev_check_source_vcpus(struct kvm *dst, struct kvm *src) 1781 { 1782 struct kvm_vcpu *src_vcpu; 1783 unsigned long i; 1784 1785 if (!sev_es_guest(src)) 1786 return 0; 1787 1788 if (atomic_read(&src->online_vcpus) != atomic_read(&dst->online_vcpus)) 1789 return -EINVAL; 1790 1791 kvm_for_each_vcpu(i, src_vcpu, src) { 1792 if (!src_vcpu->arch.guest_state_protected) 1793 return -EINVAL; 1794 } 1795 1796 return 0; 1797 } 1798 1799 int sev_vm_move_enc_context_from(struct kvm *kvm, unsigned int source_fd) 1800 { 1801 struct kvm_sev_info *dst_sev = &to_kvm_svm(kvm)->sev_info; 1802 struct kvm_sev_info *src_sev, *cg_cleanup_sev; 1803 struct fd f = fdget(source_fd); 1804 struct kvm *source_kvm; 1805 bool charged = false; 1806 int ret; 1807 1808 if (!f.file) 1809 return -EBADF; 1810 1811 if (!file_is_kvm(f.file)) { 1812 ret = -EBADF; 1813 goto out_fput; 1814 } 1815 1816 source_kvm = f.file->private_data; 1817 ret = sev_lock_two_vms(kvm, source_kvm); 1818 if (ret) 1819 goto out_fput; 1820 1821 if (sev_guest(kvm) || !sev_guest(source_kvm)) { 1822 ret = -EINVAL; 1823 goto out_unlock; 1824 } 1825 1826 src_sev = &to_kvm_svm(source_kvm)->sev_info; 1827 1828 dst_sev->misc_cg = get_current_misc_cg(); 1829 cg_cleanup_sev = dst_sev; 1830 if (dst_sev->misc_cg != src_sev->misc_cg) { 1831 ret = sev_misc_cg_try_charge(dst_sev); 1832 if (ret) 1833 goto out_dst_cgroup; 1834 charged = true; 1835 } 1836 1837 ret = sev_lock_vcpus_for_migration(kvm, SEV_MIGRATION_SOURCE); 1838 if (ret) 1839 goto out_dst_cgroup; 1840 ret = sev_lock_vcpus_for_migration(source_kvm, SEV_MIGRATION_TARGET); 1841 if (ret) 1842 goto out_dst_vcpu; 1843 1844 ret = sev_check_source_vcpus(kvm, source_kvm); 1845 if (ret) 1846 goto out_source_vcpu; 1847 1848 sev_migrate_from(kvm, source_kvm); 1849 kvm_vm_dead(source_kvm); 1850 cg_cleanup_sev = src_sev; 1851 ret = 0; 1852 1853 out_source_vcpu: 1854 sev_unlock_vcpus_for_migration(source_kvm); 1855 out_dst_vcpu: 1856 sev_unlock_vcpus_for_migration(kvm); 1857 out_dst_cgroup: 1858 /* Operates on the source on success, on the destination on failure. */ 1859 if (charged) 1860 sev_misc_cg_uncharge(cg_cleanup_sev); 1861 put_misc_cg(cg_cleanup_sev->misc_cg); 1862 cg_cleanup_sev->misc_cg = NULL; 1863 out_unlock: 1864 sev_unlock_two_vms(kvm, source_kvm); 1865 out_fput: 1866 fdput(f); 1867 return ret; 1868 } 1869 1870 int sev_mem_enc_ioctl(struct kvm *kvm, void __user *argp) 1871 { 1872 struct kvm_sev_cmd sev_cmd; 1873 int r; 1874 1875 if (!sev_enabled) 1876 return -ENOTTY; 1877 1878 if (!argp) 1879 return 0; 1880 1881 if (copy_from_user(&sev_cmd, argp, sizeof(struct kvm_sev_cmd))) 1882 return -EFAULT; 1883 1884 mutex_lock(&kvm->lock); 1885 1886 /* Only the enc_context_owner handles some memory enc operations. */ 1887 if (is_mirroring_enc_context(kvm) && 1888 !is_cmd_allowed_from_mirror(sev_cmd.id)) { 1889 r = -EINVAL; 1890 goto out; 1891 } 1892 1893 switch (sev_cmd.id) { 1894 case KVM_SEV_ES_INIT: 1895 if (!sev_es_enabled) { 1896 r = -ENOTTY; 1897 goto out; 1898 } 1899 fallthrough; 1900 case KVM_SEV_INIT: 1901 r = sev_guest_init(kvm, &sev_cmd); 1902 break; 1903 case KVM_SEV_LAUNCH_START: 1904 r = sev_launch_start(kvm, &sev_cmd); 1905 break; 1906 case KVM_SEV_LAUNCH_UPDATE_DATA: 1907 r = sev_launch_update_data(kvm, &sev_cmd); 1908 break; 1909 case KVM_SEV_LAUNCH_UPDATE_VMSA: 1910 r = sev_launch_update_vmsa(kvm, &sev_cmd); 1911 break; 1912 case KVM_SEV_LAUNCH_MEASURE: 1913 r = sev_launch_measure(kvm, &sev_cmd); 1914 break; 1915 case KVM_SEV_LAUNCH_FINISH: 1916 r = sev_launch_finish(kvm, &sev_cmd); 1917 break; 1918 case KVM_SEV_GUEST_STATUS: 1919 r = sev_guest_status(kvm, &sev_cmd); 1920 break; 1921 case KVM_SEV_DBG_DECRYPT: 1922 r = sev_dbg_crypt(kvm, &sev_cmd, true); 1923 break; 1924 case KVM_SEV_DBG_ENCRYPT: 1925 r = sev_dbg_crypt(kvm, &sev_cmd, false); 1926 break; 1927 case KVM_SEV_LAUNCH_SECRET: 1928 r = sev_launch_secret(kvm, &sev_cmd); 1929 break; 1930 case KVM_SEV_GET_ATTESTATION_REPORT: 1931 r = sev_get_attestation_report(kvm, &sev_cmd); 1932 break; 1933 case KVM_SEV_SEND_START: 1934 r = sev_send_start(kvm, &sev_cmd); 1935 break; 1936 case KVM_SEV_SEND_UPDATE_DATA: 1937 r = sev_send_update_data(kvm, &sev_cmd); 1938 break; 1939 case KVM_SEV_SEND_FINISH: 1940 r = sev_send_finish(kvm, &sev_cmd); 1941 break; 1942 case KVM_SEV_SEND_CANCEL: 1943 r = sev_send_cancel(kvm, &sev_cmd); 1944 break; 1945 case KVM_SEV_RECEIVE_START: 1946 r = sev_receive_start(kvm, &sev_cmd); 1947 break; 1948 case KVM_SEV_RECEIVE_UPDATE_DATA: 1949 r = sev_receive_update_data(kvm, &sev_cmd); 1950 break; 1951 case KVM_SEV_RECEIVE_FINISH: 1952 r = sev_receive_finish(kvm, &sev_cmd); 1953 break; 1954 default: 1955 r = -EINVAL; 1956 goto out; 1957 } 1958 1959 if (copy_to_user(argp, &sev_cmd, sizeof(struct kvm_sev_cmd))) 1960 r = -EFAULT; 1961 1962 out: 1963 mutex_unlock(&kvm->lock); 1964 return r; 1965 } 1966 1967 int sev_mem_enc_register_region(struct kvm *kvm, 1968 struct kvm_enc_region *range) 1969 { 1970 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 1971 struct enc_region *region; 1972 int ret = 0; 1973 1974 if (!sev_guest(kvm)) 1975 return -ENOTTY; 1976 1977 /* If kvm is mirroring encryption context it isn't responsible for it */ 1978 if (is_mirroring_enc_context(kvm)) 1979 return -EINVAL; 1980 1981 if (range->addr > ULONG_MAX || range->size > ULONG_MAX) 1982 return -EINVAL; 1983 1984 region = kzalloc(sizeof(*region), GFP_KERNEL_ACCOUNT); 1985 if (!region) 1986 return -ENOMEM; 1987 1988 mutex_lock(&kvm->lock); 1989 region->pages = sev_pin_memory(kvm, range->addr, range->size, ®ion->npages, 1); 1990 if (IS_ERR(region->pages)) { 1991 ret = PTR_ERR(region->pages); 1992 mutex_unlock(&kvm->lock); 1993 goto e_free; 1994 } 1995 1996 /* 1997 * The guest may change the memory encryption attribute from C=0 -> C=1 1998 * or vice versa for this memory range. Lets make sure caches are 1999 * flushed to ensure that guest data gets written into memory with 2000 * correct C-bit. Note, this must be done before dropping kvm->lock, 2001 * as region and its array of pages can be freed by a different task 2002 * once kvm->lock is released. 2003 */ 2004 sev_clflush_pages(region->pages, region->npages); 2005 2006 region->uaddr = range->addr; 2007 region->size = range->size; 2008 2009 list_add_tail(®ion->list, &sev->regions_list); 2010 mutex_unlock(&kvm->lock); 2011 2012 return ret; 2013 2014 e_free: 2015 kfree(region); 2016 return ret; 2017 } 2018 2019 static struct enc_region * 2020 find_enc_region(struct kvm *kvm, struct kvm_enc_region *range) 2021 { 2022 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 2023 struct list_head *head = &sev->regions_list; 2024 struct enc_region *i; 2025 2026 list_for_each_entry(i, head, list) { 2027 if (i->uaddr == range->addr && 2028 i->size == range->size) 2029 return i; 2030 } 2031 2032 return NULL; 2033 } 2034 2035 static void __unregister_enc_region_locked(struct kvm *kvm, 2036 struct enc_region *region) 2037 { 2038 sev_unpin_memory(kvm, region->pages, region->npages); 2039 list_del(®ion->list); 2040 kfree(region); 2041 } 2042 2043 int sev_mem_enc_unregister_region(struct kvm *kvm, 2044 struct kvm_enc_region *range) 2045 { 2046 struct enc_region *region; 2047 int ret; 2048 2049 /* If kvm is mirroring encryption context it isn't responsible for it */ 2050 if (is_mirroring_enc_context(kvm)) 2051 return -EINVAL; 2052 2053 mutex_lock(&kvm->lock); 2054 2055 if (!sev_guest(kvm)) { 2056 ret = -ENOTTY; 2057 goto failed; 2058 } 2059 2060 region = find_enc_region(kvm, range); 2061 if (!region) { 2062 ret = -EINVAL; 2063 goto failed; 2064 } 2065 2066 /* 2067 * Ensure that all guest tagged cache entries are flushed before 2068 * releasing the pages back to the system for use. CLFLUSH will 2069 * not do this, so issue a WBINVD. 2070 */ 2071 wbinvd_on_all_cpus(); 2072 2073 __unregister_enc_region_locked(kvm, region); 2074 2075 mutex_unlock(&kvm->lock); 2076 return 0; 2077 2078 failed: 2079 mutex_unlock(&kvm->lock); 2080 return ret; 2081 } 2082 2083 int sev_vm_copy_enc_context_from(struct kvm *kvm, unsigned int source_fd) 2084 { 2085 struct fd f = fdget(source_fd); 2086 struct kvm *source_kvm; 2087 struct kvm_sev_info *source_sev, *mirror_sev; 2088 int ret; 2089 2090 if (!f.file) 2091 return -EBADF; 2092 2093 if (!file_is_kvm(f.file)) { 2094 ret = -EBADF; 2095 goto e_source_fput; 2096 } 2097 2098 source_kvm = f.file->private_data; 2099 ret = sev_lock_two_vms(kvm, source_kvm); 2100 if (ret) 2101 goto e_source_fput; 2102 2103 /* 2104 * Mirrors of mirrors should work, but let's not get silly. Also 2105 * disallow out-of-band SEV/SEV-ES init if the target is already an 2106 * SEV guest, or if vCPUs have been created. KVM relies on vCPUs being 2107 * created after SEV/SEV-ES initialization, e.g. to init intercepts. 2108 */ 2109 if (sev_guest(kvm) || !sev_guest(source_kvm) || 2110 is_mirroring_enc_context(source_kvm) || kvm->created_vcpus) { 2111 ret = -EINVAL; 2112 goto e_unlock; 2113 } 2114 2115 /* 2116 * The mirror kvm holds an enc_context_owner ref so its asid can't 2117 * disappear until we're done with it 2118 */ 2119 source_sev = &to_kvm_svm(source_kvm)->sev_info; 2120 kvm_get_kvm(source_kvm); 2121 mirror_sev = &to_kvm_svm(kvm)->sev_info; 2122 list_add_tail(&mirror_sev->mirror_entry, &source_sev->mirror_vms); 2123 2124 /* Set enc_context_owner and copy its encryption context over */ 2125 mirror_sev->enc_context_owner = source_kvm; 2126 mirror_sev->active = true; 2127 mirror_sev->asid = source_sev->asid; 2128 mirror_sev->fd = source_sev->fd; 2129 mirror_sev->es_active = source_sev->es_active; 2130 mirror_sev->handle = source_sev->handle; 2131 INIT_LIST_HEAD(&mirror_sev->regions_list); 2132 INIT_LIST_HEAD(&mirror_sev->mirror_vms); 2133 ret = 0; 2134 2135 /* 2136 * Do not copy ap_jump_table. Since the mirror does not share the same 2137 * KVM contexts as the original, and they may have different 2138 * memory-views. 2139 */ 2140 2141 e_unlock: 2142 sev_unlock_two_vms(kvm, source_kvm); 2143 e_source_fput: 2144 fdput(f); 2145 return ret; 2146 } 2147 2148 void sev_vm_destroy(struct kvm *kvm) 2149 { 2150 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 2151 struct list_head *head = &sev->regions_list; 2152 struct list_head *pos, *q; 2153 2154 if (!sev_guest(kvm)) 2155 return; 2156 2157 WARN_ON(!list_empty(&sev->mirror_vms)); 2158 2159 /* If this is a mirror_kvm release the enc_context_owner and skip sev cleanup */ 2160 if (is_mirroring_enc_context(kvm)) { 2161 struct kvm *owner_kvm = sev->enc_context_owner; 2162 2163 mutex_lock(&owner_kvm->lock); 2164 list_del(&sev->mirror_entry); 2165 mutex_unlock(&owner_kvm->lock); 2166 kvm_put_kvm(owner_kvm); 2167 return; 2168 } 2169 2170 /* 2171 * Ensure that all guest tagged cache entries are flushed before 2172 * releasing the pages back to the system for use. CLFLUSH will 2173 * not do this, so issue a WBINVD. 2174 */ 2175 wbinvd_on_all_cpus(); 2176 2177 /* 2178 * if userspace was terminated before unregistering the memory regions 2179 * then lets unpin all the registered memory. 2180 */ 2181 if (!list_empty(head)) { 2182 list_for_each_safe(pos, q, head) { 2183 __unregister_enc_region_locked(kvm, 2184 list_entry(pos, struct enc_region, list)); 2185 cond_resched(); 2186 } 2187 } 2188 2189 sev_unbind_asid(kvm, sev->handle); 2190 sev_asid_free(sev); 2191 } 2192 2193 void __init sev_set_cpu_caps(void) 2194 { 2195 if (!sev_enabled) 2196 kvm_cpu_cap_clear(X86_FEATURE_SEV); 2197 if (!sev_es_enabled) 2198 kvm_cpu_cap_clear(X86_FEATURE_SEV_ES); 2199 } 2200 2201 void __init sev_hardware_setup(void) 2202 { 2203 #ifdef CONFIG_KVM_AMD_SEV 2204 unsigned int eax, ebx, ecx, edx, sev_asid_count, sev_es_asid_count; 2205 bool sev_es_supported = false; 2206 bool sev_supported = false; 2207 2208 if (!sev_enabled || !npt_enabled || !nrips) 2209 goto out; 2210 2211 /* 2212 * SEV must obviously be supported in hardware. Sanity check that the 2213 * CPU supports decode assists, which is mandatory for SEV guests to 2214 * support instruction emulation. 2215 */ 2216 if (!boot_cpu_has(X86_FEATURE_SEV) || 2217 WARN_ON_ONCE(!boot_cpu_has(X86_FEATURE_DECODEASSISTS))) 2218 goto out; 2219 2220 /* Retrieve SEV CPUID information */ 2221 cpuid(0x8000001f, &eax, &ebx, &ecx, &edx); 2222 2223 /* Set encryption bit location for SEV-ES guests */ 2224 sev_enc_bit = ebx & 0x3f; 2225 2226 /* Maximum number of encrypted guests supported simultaneously */ 2227 max_sev_asid = ecx; 2228 if (!max_sev_asid) 2229 goto out; 2230 2231 /* Minimum ASID value that should be used for SEV guest */ 2232 min_sev_asid = edx; 2233 sev_me_mask = 1UL << (ebx & 0x3f); 2234 2235 /* 2236 * Initialize SEV ASID bitmaps. Allocate space for ASID 0 in the bitmap, 2237 * even though it's never used, so that the bitmap is indexed by the 2238 * actual ASID. 2239 */ 2240 nr_asids = max_sev_asid + 1; 2241 sev_asid_bitmap = bitmap_zalloc(nr_asids, GFP_KERNEL); 2242 if (!sev_asid_bitmap) 2243 goto out; 2244 2245 sev_reclaim_asid_bitmap = bitmap_zalloc(nr_asids, GFP_KERNEL); 2246 if (!sev_reclaim_asid_bitmap) { 2247 bitmap_free(sev_asid_bitmap); 2248 sev_asid_bitmap = NULL; 2249 goto out; 2250 } 2251 2252 if (min_sev_asid <= max_sev_asid) { 2253 sev_asid_count = max_sev_asid - min_sev_asid + 1; 2254 WARN_ON_ONCE(misc_cg_set_capacity(MISC_CG_RES_SEV, sev_asid_count)); 2255 } 2256 sev_supported = true; 2257 2258 /* SEV-ES support requested? */ 2259 if (!sev_es_enabled) 2260 goto out; 2261 2262 /* 2263 * SEV-ES requires MMIO caching as KVM doesn't have access to the guest 2264 * instruction stream, i.e. can't emulate in response to a #NPF and 2265 * instead relies on #NPF(RSVD) being reflected into the guest as #VC 2266 * (the guest can then do a #VMGEXIT to request MMIO emulation). 2267 */ 2268 if (!enable_mmio_caching) 2269 goto out; 2270 2271 /* Does the CPU support SEV-ES? */ 2272 if (!boot_cpu_has(X86_FEATURE_SEV_ES)) 2273 goto out; 2274 2275 if (!lbrv) { 2276 WARN_ONCE(!boot_cpu_has(X86_FEATURE_LBRV), 2277 "LBRV must be present for SEV-ES support"); 2278 goto out; 2279 } 2280 2281 /* Has the system been allocated ASIDs for SEV-ES? */ 2282 if (min_sev_asid == 1) 2283 goto out; 2284 2285 sev_es_asid_count = min_sev_asid - 1; 2286 WARN_ON_ONCE(misc_cg_set_capacity(MISC_CG_RES_SEV_ES, sev_es_asid_count)); 2287 sev_es_supported = true; 2288 2289 out: 2290 if (boot_cpu_has(X86_FEATURE_SEV)) 2291 pr_info("SEV %s (ASIDs %u - %u)\n", 2292 sev_supported ? min_sev_asid <= max_sev_asid ? "enabled" : 2293 "unusable" : 2294 "disabled", 2295 min_sev_asid, max_sev_asid); 2296 if (boot_cpu_has(X86_FEATURE_SEV_ES)) 2297 pr_info("SEV-ES %s (ASIDs %u - %u)\n", 2298 sev_es_supported ? "enabled" : "disabled", 2299 min_sev_asid > 1 ? 1 : 0, min_sev_asid - 1); 2300 2301 sev_enabled = sev_supported; 2302 sev_es_enabled = sev_es_supported; 2303 if (!sev_es_enabled || !cpu_feature_enabled(X86_FEATURE_DEBUG_SWAP) || 2304 !cpu_feature_enabled(X86_FEATURE_NO_NESTED_DATA_BP)) 2305 sev_es_debug_swap_enabled = false; 2306 #endif 2307 } 2308 2309 void sev_hardware_unsetup(void) 2310 { 2311 if (!sev_enabled) 2312 return; 2313 2314 /* No need to take sev_bitmap_lock, all VMs have been destroyed. */ 2315 sev_flush_asids(1, max_sev_asid); 2316 2317 bitmap_free(sev_asid_bitmap); 2318 bitmap_free(sev_reclaim_asid_bitmap); 2319 2320 misc_cg_set_capacity(MISC_CG_RES_SEV, 0); 2321 misc_cg_set_capacity(MISC_CG_RES_SEV_ES, 0); 2322 } 2323 2324 int sev_cpu_init(struct svm_cpu_data *sd) 2325 { 2326 if (!sev_enabled) 2327 return 0; 2328 2329 sd->sev_vmcbs = kcalloc(nr_asids, sizeof(void *), GFP_KERNEL); 2330 if (!sd->sev_vmcbs) 2331 return -ENOMEM; 2332 2333 return 0; 2334 } 2335 2336 /* 2337 * Pages used by hardware to hold guest encrypted state must be flushed before 2338 * returning them to the system. 2339 */ 2340 static void sev_flush_encrypted_page(struct kvm_vcpu *vcpu, void *va) 2341 { 2342 unsigned int asid = sev_get_asid(vcpu->kvm); 2343 2344 /* 2345 * Note! The address must be a kernel address, as regular page walk 2346 * checks are performed by VM_PAGE_FLUSH, i.e. operating on a user 2347 * address is non-deterministic and unsafe. This function deliberately 2348 * takes a pointer to deter passing in a user address. 2349 */ 2350 unsigned long addr = (unsigned long)va; 2351 2352 /* 2353 * If CPU enforced cache coherency for encrypted mappings of the 2354 * same physical page is supported, use CLFLUSHOPT instead. NOTE: cache 2355 * flush is still needed in order to work properly with DMA devices. 2356 */ 2357 if (boot_cpu_has(X86_FEATURE_SME_COHERENT)) { 2358 clflush_cache_range(va, PAGE_SIZE); 2359 return; 2360 } 2361 2362 /* 2363 * VM Page Flush takes a host virtual address and a guest ASID. Fall 2364 * back to WBINVD if this faults so as not to make any problems worse 2365 * by leaving stale encrypted data in the cache. 2366 */ 2367 if (WARN_ON_ONCE(wrmsrl_safe(MSR_AMD64_VM_PAGE_FLUSH, addr | asid))) 2368 goto do_wbinvd; 2369 2370 return; 2371 2372 do_wbinvd: 2373 wbinvd_on_all_cpus(); 2374 } 2375 2376 void sev_guest_memory_reclaimed(struct kvm *kvm) 2377 { 2378 if (!sev_guest(kvm)) 2379 return; 2380 2381 wbinvd_on_all_cpus(); 2382 } 2383 2384 void sev_free_vcpu(struct kvm_vcpu *vcpu) 2385 { 2386 struct vcpu_svm *svm; 2387 2388 if (!sev_es_guest(vcpu->kvm)) 2389 return; 2390 2391 svm = to_svm(vcpu); 2392 2393 if (vcpu->arch.guest_state_protected) 2394 sev_flush_encrypted_page(vcpu, svm->sev_es.vmsa); 2395 2396 __free_page(virt_to_page(svm->sev_es.vmsa)); 2397 2398 if (svm->sev_es.ghcb_sa_free) 2399 kvfree(svm->sev_es.ghcb_sa); 2400 } 2401 2402 static void dump_ghcb(struct vcpu_svm *svm) 2403 { 2404 struct ghcb *ghcb = svm->sev_es.ghcb; 2405 unsigned int nbits; 2406 2407 /* Re-use the dump_invalid_vmcb module parameter */ 2408 if (!dump_invalid_vmcb) { 2409 pr_warn_ratelimited("set kvm_amd.dump_invalid_vmcb=1 to dump internal KVM state.\n"); 2410 return; 2411 } 2412 2413 nbits = sizeof(ghcb->save.valid_bitmap) * 8; 2414 2415 pr_err("GHCB (GPA=%016llx):\n", svm->vmcb->control.ghcb_gpa); 2416 pr_err("%-20s%016llx is_valid: %u\n", "sw_exit_code", 2417 ghcb->save.sw_exit_code, ghcb_sw_exit_code_is_valid(ghcb)); 2418 pr_err("%-20s%016llx is_valid: %u\n", "sw_exit_info_1", 2419 ghcb->save.sw_exit_info_1, ghcb_sw_exit_info_1_is_valid(ghcb)); 2420 pr_err("%-20s%016llx is_valid: %u\n", "sw_exit_info_2", 2421 ghcb->save.sw_exit_info_2, ghcb_sw_exit_info_2_is_valid(ghcb)); 2422 pr_err("%-20s%016llx is_valid: %u\n", "sw_scratch", 2423 ghcb->save.sw_scratch, ghcb_sw_scratch_is_valid(ghcb)); 2424 pr_err("%-20s%*pb\n", "valid_bitmap", nbits, ghcb->save.valid_bitmap); 2425 } 2426 2427 static void sev_es_sync_to_ghcb(struct vcpu_svm *svm) 2428 { 2429 struct kvm_vcpu *vcpu = &svm->vcpu; 2430 struct ghcb *ghcb = svm->sev_es.ghcb; 2431 2432 /* 2433 * The GHCB protocol so far allows for the following data 2434 * to be returned: 2435 * GPRs RAX, RBX, RCX, RDX 2436 * 2437 * Copy their values, even if they may not have been written during the 2438 * VM-Exit. It's the guest's responsibility to not consume random data. 2439 */ 2440 ghcb_set_rax(ghcb, vcpu->arch.regs[VCPU_REGS_RAX]); 2441 ghcb_set_rbx(ghcb, vcpu->arch.regs[VCPU_REGS_RBX]); 2442 ghcb_set_rcx(ghcb, vcpu->arch.regs[VCPU_REGS_RCX]); 2443 ghcb_set_rdx(ghcb, vcpu->arch.regs[VCPU_REGS_RDX]); 2444 } 2445 2446 static void sev_es_sync_from_ghcb(struct vcpu_svm *svm) 2447 { 2448 struct vmcb_control_area *control = &svm->vmcb->control; 2449 struct kvm_vcpu *vcpu = &svm->vcpu; 2450 struct ghcb *ghcb = svm->sev_es.ghcb; 2451 u64 exit_code; 2452 2453 /* 2454 * The GHCB protocol so far allows for the following data 2455 * to be supplied: 2456 * GPRs RAX, RBX, RCX, RDX 2457 * XCR0 2458 * CPL 2459 * 2460 * VMMCALL allows the guest to provide extra registers. KVM also 2461 * expects RSI for hypercalls, so include that, too. 2462 * 2463 * Copy their values to the appropriate location if supplied. 2464 */ 2465 memset(vcpu->arch.regs, 0, sizeof(vcpu->arch.regs)); 2466 2467 BUILD_BUG_ON(sizeof(svm->sev_es.valid_bitmap) != sizeof(ghcb->save.valid_bitmap)); 2468 memcpy(&svm->sev_es.valid_bitmap, &ghcb->save.valid_bitmap, sizeof(ghcb->save.valid_bitmap)); 2469 2470 vcpu->arch.regs[VCPU_REGS_RAX] = kvm_ghcb_get_rax_if_valid(svm, ghcb); 2471 vcpu->arch.regs[VCPU_REGS_RBX] = kvm_ghcb_get_rbx_if_valid(svm, ghcb); 2472 vcpu->arch.regs[VCPU_REGS_RCX] = kvm_ghcb_get_rcx_if_valid(svm, ghcb); 2473 vcpu->arch.regs[VCPU_REGS_RDX] = kvm_ghcb_get_rdx_if_valid(svm, ghcb); 2474 vcpu->arch.regs[VCPU_REGS_RSI] = kvm_ghcb_get_rsi_if_valid(svm, ghcb); 2475 2476 svm->vmcb->save.cpl = kvm_ghcb_get_cpl_if_valid(svm, ghcb); 2477 2478 if (kvm_ghcb_xcr0_is_valid(svm)) { 2479 vcpu->arch.xcr0 = ghcb_get_xcr0(ghcb); 2480 kvm_update_cpuid_runtime(vcpu); 2481 } 2482 2483 /* Copy the GHCB exit information into the VMCB fields */ 2484 exit_code = ghcb_get_sw_exit_code(ghcb); 2485 control->exit_code = lower_32_bits(exit_code); 2486 control->exit_code_hi = upper_32_bits(exit_code); 2487 control->exit_info_1 = ghcb_get_sw_exit_info_1(ghcb); 2488 control->exit_info_2 = ghcb_get_sw_exit_info_2(ghcb); 2489 svm->sev_es.sw_scratch = kvm_ghcb_get_sw_scratch_if_valid(svm, ghcb); 2490 2491 /* Clear the valid entries fields */ 2492 memset(ghcb->save.valid_bitmap, 0, sizeof(ghcb->save.valid_bitmap)); 2493 } 2494 2495 static u64 kvm_ghcb_get_sw_exit_code(struct vmcb_control_area *control) 2496 { 2497 return (((u64)control->exit_code_hi) << 32) | control->exit_code; 2498 } 2499 2500 static int sev_es_validate_vmgexit(struct vcpu_svm *svm) 2501 { 2502 struct vmcb_control_area *control = &svm->vmcb->control; 2503 struct kvm_vcpu *vcpu = &svm->vcpu; 2504 u64 exit_code; 2505 u64 reason; 2506 2507 /* 2508 * Retrieve the exit code now even though it may not be marked valid 2509 * as it could help with debugging. 2510 */ 2511 exit_code = kvm_ghcb_get_sw_exit_code(control); 2512 2513 /* Only GHCB Usage code 0 is supported */ 2514 if (svm->sev_es.ghcb->ghcb_usage) { 2515 reason = GHCB_ERR_INVALID_USAGE; 2516 goto vmgexit_err; 2517 } 2518 2519 reason = GHCB_ERR_MISSING_INPUT; 2520 2521 if (!kvm_ghcb_sw_exit_code_is_valid(svm) || 2522 !kvm_ghcb_sw_exit_info_1_is_valid(svm) || 2523 !kvm_ghcb_sw_exit_info_2_is_valid(svm)) 2524 goto vmgexit_err; 2525 2526 switch (exit_code) { 2527 case SVM_EXIT_READ_DR7: 2528 break; 2529 case SVM_EXIT_WRITE_DR7: 2530 if (!kvm_ghcb_rax_is_valid(svm)) 2531 goto vmgexit_err; 2532 break; 2533 case SVM_EXIT_RDTSC: 2534 break; 2535 case SVM_EXIT_RDPMC: 2536 if (!kvm_ghcb_rcx_is_valid(svm)) 2537 goto vmgexit_err; 2538 break; 2539 case SVM_EXIT_CPUID: 2540 if (!kvm_ghcb_rax_is_valid(svm) || 2541 !kvm_ghcb_rcx_is_valid(svm)) 2542 goto vmgexit_err; 2543 if (vcpu->arch.regs[VCPU_REGS_RAX] == 0xd) 2544 if (!kvm_ghcb_xcr0_is_valid(svm)) 2545 goto vmgexit_err; 2546 break; 2547 case SVM_EXIT_INVD: 2548 break; 2549 case SVM_EXIT_IOIO: 2550 if (control->exit_info_1 & SVM_IOIO_STR_MASK) { 2551 if (!kvm_ghcb_sw_scratch_is_valid(svm)) 2552 goto vmgexit_err; 2553 } else { 2554 if (!(control->exit_info_1 & SVM_IOIO_TYPE_MASK)) 2555 if (!kvm_ghcb_rax_is_valid(svm)) 2556 goto vmgexit_err; 2557 } 2558 break; 2559 case SVM_EXIT_MSR: 2560 if (!kvm_ghcb_rcx_is_valid(svm)) 2561 goto vmgexit_err; 2562 if (control->exit_info_1) { 2563 if (!kvm_ghcb_rax_is_valid(svm) || 2564 !kvm_ghcb_rdx_is_valid(svm)) 2565 goto vmgexit_err; 2566 } 2567 break; 2568 case SVM_EXIT_VMMCALL: 2569 if (!kvm_ghcb_rax_is_valid(svm) || 2570 !kvm_ghcb_cpl_is_valid(svm)) 2571 goto vmgexit_err; 2572 break; 2573 case SVM_EXIT_RDTSCP: 2574 break; 2575 case SVM_EXIT_WBINVD: 2576 break; 2577 case SVM_EXIT_MONITOR: 2578 if (!kvm_ghcb_rax_is_valid(svm) || 2579 !kvm_ghcb_rcx_is_valid(svm) || 2580 !kvm_ghcb_rdx_is_valid(svm)) 2581 goto vmgexit_err; 2582 break; 2583 case SVM_EXIT_MWAIT: 2584 if (!kvm_ghcb_rax_is_valid(svm) || 2585 !kvm_ghcb_rcx_is_valid(svm)) 2586 goto vmgexit_err; 2587 break; 2588 case SVM_VMGEXIT_MMIO_READ: 2589 case SVM_VMGEXIT_MMIO_WRITE: 2590 if (!kvm_ghcb_sw_scratch_is_valid(svm)) 2591 goto vmgexit_err; 2592 break; 2593 case SVM_VMGEXIT_NMI_COMPLETE: 2594 case SVM_VMGEXIT_AP_HLT_LOOP: 2595 case SVM_VMGEXIT_AP_JUMP_TABLE: 2596 case SVM_VMGEXIT_UNSUPPORTED_EVENT: 2597 break; 2598 default: 2599 reason = GHCB_ERR_INVALID_EVENT; 2600 goto vmgexit_err; 2601 } 2602 2603 return 0; 2604 2605 vmgexit_err: 2606 if (reason == GHCB_ERR_INVALID_USAGE) { 2607 vcpu_unimpl(vcpu, "vmgexit: ghcb usage %#x is not valid\n", 2608 svm->sev_es.ghcb->ghcb_usage); 2609 } else if (reason == GHCB_ERR_INVALID_EVENT) { 2610 vcpu_unimpl(vcpu, "vmgexit: exit code %#llx is not valid\n", 2611 exit_code); 2612 } else { 2613 vcpu_unimpl(vcpu, "vmgexit: exit code %#llx input is not valid\n", 2614 exit_code); 2615 dump_ghcb(svm); 2616 } 2617 2618 ghcb_set_sw_exit_info_1(svm->sev_es.ghcb, 2); 2619 ghcb_set_sw_exit_info_2(svm->sev_es.ghcb, reason); 2620 2621 /* Resume the guest to "return" the error code. */ 2622 return 1; 2623 } 2624 2625 void sev_es_unmap_ghcb(struct vcpu_svm *svm) 2626 { 2627 if (!svm->sev_es.ghcb) 2628 return; 2629 2630 if (svm->sev_es.ghcb_sa_free) { 2631 /* 2632 * The scratch area lives outside the GHCB, so there is a 2633 * buffer that, depending on the operation performed, may 2634 * need to be synced, then freed. 2635 */ 2636 if (svm->sev_es.ghcb_sa_sync) { 2637 kvm_write_guest(svm->vcpu.kvm, 2638 svm->sev_es.sw_scratch, 2639 svm->sev_es.ghcb_sa, 2640 svm->sev_es.ghcb_sa_len); 2641 svm->sev_es.ghcb_sa_sync = false; 2642 } 2643 2644 kvfree(svm->sev_es.ghcb_sa); 2645 svm->sev_es.ghcb_sa = NULL; 2646 svm->sev_es.ghcb_sa_free = false; 2647 } 2648 2649 trace_kvm_vmgexit_exit(svm->vcpu.vcpu_id, svm->sev_es.ghcb); 2650 2651 sev_es_sync_to_ghcb(svm); 2652 2653 kvm_vcpu_unmap(&svm->vcpu, &svm->sev_es.ghcb_map, true); 2654 svm->sev_es.ghcb = NULL; 2655 } 2656 2657 void pre_sev_run(struct vcpu_svm *svm, int cpu) 2658 { 2659 struct svm_cpu_data *sd = per_cpu_ptr(&svm_data, cpu); 2660 unsigned int asid = sev_get_asid(svm->vcpu.kvm); 2661 2662 /* Assign the asid allocated with this SEV guest */ 2663 svm->asid = asid; 2664 2665 /* 2666 * Flush guest TLB: 2667 * 2668 * 1) when different VMCB for the same ASID is to be run on the same host CPU. 2669 * 2) or this VMCB was executed on different host CPU in previous VMRUNs. 2670 */ 2671 if (sd->sev_vmcbs[asid] == svm->vmcb && 2672 svm->vcpu.arch.last_vmentry_cpu == cpu) 2673 return; 2674 2675 sd->sev_vmcbs[asid] = svm->vmcb; 2676 svm->vmcb->control.tlb_ctl = TLB_CONTROL_FLUSH_ASID; 2677 vmcb_mark_dirty(svm->vmcb, VMCB_ASID); 2678 } 2679 2680 #define GHCB_SCRATCH_AREA_LIMIT (16ULL * PAGE_SIZE) 2681 static int setup_vmgexit_scratch(struct vcpu_svm *svm, bool sync, u64 len) 2682 { 2683 struct vmcb_control_area *control = &svm->vmcb->control; 2684 u64 ghcb_scratch_beg, ghcb_scratch_end; 2685 u64 scratch_gpa_beg, scratch_gpa_end; 2686 void *scratch_va; 2687 2688 scratch_gpa_beg = svm->sev_es.sw_scratch; 2689 if (!scratch_gpa_beg) { 2690 pr_err("vmgexit: scratch gpa not provided\n"); 2691 goto e_scratch; 2692 } 2693 2694 scratch_gpa_end = scratch_gpa_beg + len; 2695 if (scratch_gpa_end < scratch_gpa_beg) { 2696 pr_err("vmgexit: scratch length (%#llx) not valid for scratch address (%#llx)\n", 2697 len, scratch_gpa_beg); 2698 goto e_scratch; 2699 } 2700 2701 if ((scratch_gpa_beg & PAGE_MASK) == control->ghcb_gpa) { 2702 /* Scratch area begins within GHCB */ 2703 ghcb_scratch_beg = control->ghcb_gpa + 2704 offsetof(struct ghcb, shared_buffer); 2705 ghcb_scratch_end = control->ghcb_gpa + 2706 offsetof(struct ghcb, reserved_0xff0); 2707 2708 /* 2709 * If the scratch area begins within the GHCB, it must be 2710 * completely contained in the GHCB shared buffer area. 2711 */ 2712 if (scratch_gpa_beg < ghcb_scratch_beg || 2713 scratch_gpa_end > ghcb_scratch_end) { 2714 pr_err("vmgexit: scratch area is outside of GHCB shared buffer area (%#llx - %#llx)\n", 2715 scratch_gpa_beg, scratch_gpa_end); 2716 goto e_scratch; 2717 } 2718 2719 scratch_va = (void *)svm->sev_es.ghcb; 2720 scratch_va += (scratch_gpa_beg - control->ghcb_gpa); 2721 } else { 2722 /* 2723 * The guest memory must be read into a kernel buffer, so 2724 * limit the size 2725 */ 2726 if (len > GHCB_SCRATCH_AREA_LIMIT) { 2727 pr_err("vmgexit: scratch area exceeds KVM limits (%#llx requested, %#llx limit)\n", 2728 len, GHCB_SCRATCH_AREA_LIMIT); 2729 goto e_scratch; 2730 } 2731 scratch_va = kvzalloc(len, GFP_KERNEL_ACCOUNT); 2732 if (!scratch_va) 2733 return -ENOMEM; 2734 2735 if (kvm_read_guest(svm->vcpu.kvm, scratch_gpa_beg, scratch_va, len)) { 2736 /* Unable to copy scratch area from guest */ 2737 pr_err("vmgexit: kvm_read_guest for scratch area failed\n"); 2738 2739 kvfree(scratch_va); 2740 return -EFAULT; 2741 } 2742 2743 /* 2744 * The scratch area is outside the GHCB. The operation will 2745 * dictate whether the buffer needs to be synced before running 2746 * the vCPU next time (i.e. a read was requested so the data 2747 * must be written back to the guest memory). 2748 */ 2749 svm->sev_es.ghcb_sa_sync = sync; 2750 svm->sev_es.ghcb_sa_free = true; 2751 } 2752 2753 svm->sev_es.ghcb_sa = scratch_va; 2754 svm->sev_es.ghcb_sa_len = len; 2755 2756 return 0; 2757 2758 e_scratch: 2759 ghcb_set_sw_exit_info_1(svm->sev_es.ghcb, 2); 2760 ghcb_set_sw_exit_info_2(svm->sev_es.ghcb, GHCB_ERR_INVALID_SCRATCH_AREA); 2761 2762 return 1; 2763 } 2764 2765 static void set_ghcb_msr_bits(struct vcpu_svm *svm, u64 value, u64 mask, 2766 unsigned int pos) 2767 { 2768 svm->vmcb->control.ghcb_gpa &= ~(mask << pos); 2769 svm->vmcb->control.ghcb_gpa |= (value & mask) << pos; 2770 } 2771 2772 static u64 get_ghcb_msr_bits(struct vcpu_svm *svm, u64 mask, unsigned int pos) 2773 { 2774 return (svm->vmcb->control.ghcb_gpa >> pos) & mask; 2775 } 2776 2777 static void set_ghcb_msr(struct vcpu_svm *svm, u64 value) 2778 { 2779 svm->vmcb->control.ghcb_gpa = value; 2780 } 2781 2782 static int sev_handle_vmgexit_msr_protocol(struct vcpu_svm *svm) 2783 { 2784 struct vmcb_control_area *control = &svm->vmcb->control; 2785 struct kvm_vcpu *vcpu = &svm->vcpu; 2786 u64 ghcb_info; 2787 int ret = 1; 2788 2789 ghcb_info = control->ghcb_gpa & GHCB_MSR_INFO_MASK; 2790 2791 trace_kvm_vmgexit_msr_protocol_enter(svm->vcpu.vcpu_id, 2792 control->ghcb_gpa); 2793 2794 switch (ghcb_info) { 2795 case GHCB_MSR_SEV_INFO_REQ: 2796 set_ghcb_msr(svm, GHCB_MSR_SEV_INFO(GHCB_VERSION_MAX, 2797 GHCB_VERSION_MIN, 2798 sev_enc_bit)); 2799 break; 2800 case GHCB_MSR_CPUID_REQ: { 2801 u64 cpuid_fn, cpuid_reg, cpuid_value; 2802 2803 cpuid_fn = get_ghcb_msr_bits(svm, 2804 GHCB_MSR_CPUID_FUNC_MASK, 2805 GHCB_MSR_CPUID_FUNC_POS); 2806 2807 /* Initialize the registers needed by the CPUID intercept */ 2808 vcpu->arch.regs[VCPU_REGS_RAX] = cpuid_fn; 2809 vcpu->arch.regs[VCPU_REGS_RCX] = 0; 2810 2811 ret = svm_invoke_exit_handler(vcpu, SVM_EXIT_CPUID); 2812 if (!ret) { 2813 /* Error, keep GHCB MSR value as-is */ 2814 break; 2815 } 2816 2817 cpuid_reg = get_ghcb_msr_bits(svm, 2818 GHCB_MSR_CPUID_REG_MASK, 2819 GHCB_MSR_CPUID_REG_POS); 2820 if (cpuid_reg == 0) 2821 cpuid_value = vcpu->arch.regs[VCPU_REGS_RAX]; 2822 else if (cpuid_reg == 1) 2823 cpuid_value = vcpu->arch.regs[VCPU_REGS_RBX]; 2824 else if (cpuid_reg == 2) 2825 cpuid_value = vcpu->arch.regs[VCPU_REGS_RCX]; 2826 else 2827 cpuid_value = vcpu->arch.regs[VCPU_REGS_RDX]; 2828 2829 set_ghcb_msr_bits(svm, cpuid_value, 2830 GHCB_MSR_CPUID_VALUE_MASK, 2831 GHCB_MSR_CPUID_VALUE_POS); 2832 2833 set_ghcb_msr_bits(svm, GHCB_MSR_CPUID_RESP, 2834 GHCB_MSR_INFO_MASK, 2835 GHCB_MSR_INFO_POS); 2836 break; 2837 } 2838 case GHCB_MSR_TERM_REQ: { 2839 u64 reason_set, reason_code; 2840 2841 reason_set = get_ghcb_msr_bits(svm, 2842 GHCB_MSR_TERM_REASON_SET_MASK, 2843 GHCB_MSR_TERM_REASON_SET_POS); 2844 reason_code = get_ghcb_msr_bits(svm, 2845 GHCB_MSR_TERM_REASON_MASK, 2846 GHCB_MSR_TERM_REASON_POS); 2847 pr_info("SEV-ES guest requested termination: %#llx:%#llx\n", 2848 reason_set, reason_code); 2849 2850 vcpu->run->exit_reason = KVM_EXIT_SYSTEM_EVENT; 2851 vcpu->run->system_event.type = KVM_SYSTEM_EVENT_SEV_TERM; 2852 vcpu->run->system_event.ndata = 1; 2853 vcpu->run->system_event.data[0] = control->ghcb_gpa; 2854 2855 return 0; 2856 } 2857 default: 2858 /* Error, keep GHCB MSR value as-is */ 2859 break; 2860 } 2861 2862 trace_kvm_vmgexit_msr_protocol_exit(svm->vcpu.vcpu_id, 2863 control->ghcb_gpa, ret); 2864 2865 return ret; 2866 } 2867 2868 int sev_handle_vmgexit(struct kvm_vcpu *vcpu) 2869 { 2870 struct vcpu_svm *svm = to_svm(vcpu); 2871 struct vmcb_control_area *control = &svm->vmcb->control; 2872 u64 ghcb_gpa, exit_code; 2873 int ret; 2874 2875 /* Validate the GHCB */ 2876 ghcb_gpa = control->ghcb_gpa; 2877 if (ghcb_gpa & GHCB_MSR_INFO_MASK) 2878 return sev_handle_vmgexit_msr_protocol(svm); 2879 2880 if (!ghcb_gpa) { 2881 vcpu_unimpl(vcpu, "vmgexit: GHCB gpa is not set\n"); 2882 2883 /* Without a GHCB, just return right back to the guest */ 2884 return 1; 2885 } 2886 2887 if (kvm_vcpu_map(vcpu, ghcb_gpa >> PAGE_SHIFT, &svm->sev_es.ghcb_map)) { 2888 /* Unable to map GHCB from guest */ 2889 vcpu_unimpl(vcpu, "vmgexit: error mapping GHCB [%#llx] from guest\n", 2890 ghcb_gpa); 2891 2892 /* Without a GHCB, just return right back to the guest */ 2893 return 1; 2894 } 2895 2896 svm->sev_es.ghcb = svm->sev_es.ghcb_map.hva; 2897 2898 trace_kvm_vmgexit_enter(vcpu->vcpu_id, svm->sev_es.ghcb); 2899 2900 sev_es_sync_from_ghcb(svm); 2901 ret = sev_es_validate_vmgexit(svm); 2902 if (ret) 2903 return ret; 2904 2905 ghcb_set_sw_exit_info_1(svm->sev_es.ghcb, 0); 2906 ghcb_set_sw_exit_info_2(svm->sev_es.ghcb, 0); 2907 2908 exit_code = kvm_ghcb_get_sw_exit_code(control); 2909 switch (exit_code) { 2910 case SVM_VMGEXIT_MMIO_READ: 2911 ret = setup_vmgexit_scratch(svm, true, control->exit_info_2); 2912 if (ret) 2913 break; 2914 2915 ret = kvm_sev_es_mmio_read(vcpu, 2916 control->exit_info_1, 2917 control->exit_info_2, 2918 svm->sev_es.ghcb_sa); 2919 break; 2920 case SVM_VMGEXIT_MMIO_WRITE: 2921 ret = setup_vmgexit_scratch(svm, false, control->exit_info_2); 2922 if (ret) 2923 break; 2924 2925 ret = kvm_sev_es_mmio_write(vcpu, 2926 control->exit_info_1, 2927 control->exit_info_2, 2928 svm->sev_es.ghcb_sa); 2929 break; 2930 case SVM_VMGEXIT_NMI_COMPLETE: 2931 ++vcpu->stat.nmi_window_exits; 2932 svm->nmi_masked = false; 2933 kvm_make_request(KVM_REQ_EVENT, vcpu); 2934 ret = 1; 2935 break; 2936 case SVM_VMGEXIT_AP_HLT_LOOP: 2937 ret = kvm_emulate_ap_reset_hold(vcpu); 2938 break; 2939 case SVM_VMGEXIT_AP_JUMP_TABLE: { 2940 struct kvm_sev_info *sev = &to_kvm_svm(vcpu->kvm)->sev_info; 2941 2942 switch (control->exit_info_1) { 2943 case 0: 2944 /* Set AP jump table address */ 2945 sev->ap_jump_table = control->exit_info_2; 2946 break; 2947 case 1: 2948 /* Get AP jump table address */ 2949 ghcb_set_sw_exit_info_2(svm->sev_es.ghcb, sev->ap_jump_table); 2950 break; 2951 default: 2952 pr_err("svm: vmgexit: unsupported AP jump table request - exit_info_1=%#llx\n", 2953 control->exit_info_1); 2954 ghcb_set_sw_exit_info_1(svm->sev_es.ghcb, 2); 2955 ghcb_set_sw_exit_info_2(svm->sev_es.ghcb, GHCB_ERR_INVALID_INPUT); 2956 } 2957 2958 ret = 1; 2959 break; 2960 } 2961 case SVM_VMGEXIT_UNSUPPORTED_EVENT: 2962 vcpu_unimpl(vcpu, 2963 "vmgexit: unsupported event - exit_info_1=%#llx, exit_info_2=%#llx\n", 2964 control->exit_info_1, control->exit_info_2); 2965 ret = -EINVAL; 2966 break; 2967 default: 2968 ret = svm_invoke_exit_handler(vcpu, exit_code); 2969 } 2970 2971 return ret; 2972 } 2973 2974 int sev_es_string_io(struct vcpu_svm *svm, int size, unsigned int port, int in) 2975 { 2976 int count; 2977 int bytes; 2978 int r; 2979 2980 if (svm->vmcb->control.exit_info_2 > INT_MAX) 2981 return -EINVAL; 2982 2983 count = svm->vmcb->control.exit_info_2; 2984 if (unlikely(check_mul_overflow(count, size, &bytes))) 2985 return -EINVAL; 2986 2987 r = setup_vmgexit_scratch(svm, in, bytes); 2988 if (r) 2989 return r; 2990 2991 return kvm_sev_es_string_io(&svm->vcpu, size, port, svm->sev_es.ghcb_sa, 2992 count, in); 2993 } 2994 2995 static void sev_es_vcpu_after_set_cpuid(struct vcpu_svm *svm) 2996 { 2997 struct kvm_vcpu *vcpu = &svm->vcpu; 2998 2999 if (boot_cpu_has(X86_FEATURE_V_TSC_AUX)) { 3000 bool v_tsc_aux = guest_cpuid_has(vcpu, X86_FEATURE_RDTSCP) || 3001 guest_cpuid_has(vcpu, X86_FEATURE_RDPID); 3002 3003 set_msr_interception(vcpu, svm->msrpm, MSR_TSC_AUX, v_tsc_aux, v_tsc_aux); 3004 } 3005 3006 /* 3007 * For SEV-ES, accesses to MSR_IA32_XSS should not be intercepted if 3008 * the host/guest supports its use. 3009 * 3010 * guest_can_use() checks a number of requirements on the host/guest to 3011 * ensure that MSR_IA32_XSS is available, but it might report true even 3012 * if X86_FEATURE_XSAVES isn't configured in the guest to ensure host 3013 * MSR_IA32_XSS is always properly restored. For SEV-ES, it is better 3014 * to further check that the guest CPUID actually supports 3015 * X86_FEATURE_XSAVES so that accesses to MSR_IA32_XSS by misbehaved 3016 * guests will still get intercepted and caught in the normal 3017 * kvm_emulate_rdmsr()/kvm_emulated_wrmsr() paths. 3018 */ 3019 if (guest_can_use(vcpu, X86_FEATURE_XSAVES) && 3020 guest_cpuid_has(vcpu, X86_FEATURE_XSAVES)) 3021 set_msr_interception(vcpu, svm->msrpm, MSR_IA32_XSS, 1, 1); 3022 else 3023 set_msr_interception(vcpu, svm->msrpm, MSR_IA32_XSS, 0, 0); 3024 } 3025 3026 void sev_vcpu_after_set_cpuid(struct vcpu_svm *svm) 3027 { 3028 struct kvm_vcpu *vcpu = &svm->vcpu; 3029 struct kvm_cpuid_entry2 *best; 3030 3031 /* For sev guests, the memory encryption bit is not reserved in CR3. */ 3032 best = kvm_find_cpuid_entry(vcpu, 0x8000001F); 3033 if (best) 3034 vcpu->arch.reserved_gpa_bits &= ~(1UL << (best->ebx & 0x3f)); 3035 3036 if (sev_es_guest(svm->vcpu.kvm)) 3037 sev_es_vcpu_after_set_cpuid(svm); 3038 } 3039 3040 static void sev_es_init_vmcb(struct vcpu_svm *svm) 3041 { 3042 struct vmcb *vmcb = svm->vmcb01.ptr; 3043 struct kvm_vcpu *vcpu = &svm->vcpu; 3044 3045 svm->vmcb->control.nested_ctl |= SVM_NESTED_CTL_SEV_ES_ENABLE; 3046 3047 /* 3048 * An SEV-ES guest requires a VMSA area that is a separate from the 3049 * VMCB page. Do not include the encryption mask on the VMSA physical 3050 * address since hardware will access it using the guest key. Note, 3051 * the VMSA will be NULL if this vCPU is the destination for intrahost 3052 * migration, and will be copied later. 3053 */ 3054 if (svm->sev_es.vmsa) 3055 svm->vmcb->control.vmsa_pa = __pa(svm->sev_es.vmsa); 3056 3057 /* Can't intercept CR register access, HV can't modify CR registers */ 3058 svm_clr_intercept(svm, INTERCEPT_CR0_READ); 3059 svm_clr_intercept(svm, INTERCEPT_CR4_READ); 3060 svm_clr_intercept(svm, INTERCEPT_CR8_READ); 3061 svm_clr_intercept(svm, INTERCEPT_CR0_WRITE); 3062 svm_clr_intercept(svm, INTERCEPT_CR4_WRITE); 3063 svm_clr_intercept(svm, INTERCEPT_CR8_WRITE); 3064 3065 svm_clr_intercept(svm, INTERCEPT_SELECTIVE_CR0); 3066 3067 /* Track EFER/CR register changes */ 3068 svm_set_intercept(svm, TRAP_EFER_WRITE); 3069 svm_set_intercept(svm, TRAP_CR0_WRITE); 3070 svm_set_intercept(svm, TRAP_CR4_WRITE); 3071 svm_set_intercept(svm, TRAP_CR8_WRITE); 3072 3073 vmcb->control.intercepts[INTERCEPT_DR] = 0; 3074 if (!sev_es_debug_swap_enabled) { 3075 vmcb_set_intercept(&vmcb->control, INTERCEPT_DR7_READ); 3076 vmcb_set_intercept(&vmcb->control, INTERCEPT_DR7_WRITE); 3077 recalc_intercepts(svm); 3078 } else { 3079 /* 3080 * Disable #DB intercept iff DebugSwap is enabled. KVM doesn't 3081 * allow debugging SEV-ES guests, and enables DebugSwap iff 3082 * NO_NESTED_DATA_BP is supported, so there's no reason to 3083 * intercept #DB when DebugSwap is enabled. For simplicity 3084 * with respect to guest debug, intercept #DB for other VMs 3085 * even if NO_NESTED_DATA_BP is supported, i.e. even if the 3086 * guest can't DoS the CPU with infinite #DB vectoring. 3087 */ 3088 clr_exception_intercept(svm, DB_VECTOR); 3089 } 3090 3091 /* Can't intercept XSETBV, HV can't modify XCR0 directly */ 3092 svm_clr_intercept(svm, INTERCEPT_XSETBV); 3093 3094 /* Clear intercepts on selected MSRs */ 3095 set_msr_interception(vcpu, svm->msrpm, MSR_EFER, 1, 1); 3096 set_msr_interception(vcpu, svm->msrpm, MSR_IA32_CR_PAT, 1, 1); 3097 } 3098 3099 void sev_init_vmcb(struct vcpu_svm *svm) 3100 { 3101 svm->vmcb->control.nested_ctl |= SVM_NESTED_CTL_SEV_ENABLE; 3102 clr_exception_intercept(svm, UD_VECTOR); 3103 3104 /* 3105 * Don't intercept #GP for SEV guests, e.g. for the VMware backdoor, as 3106 * KVM can't decrypt guest memory to decode the faulting instruction. 3107 */ 3108 clr_exception_intercept(svm, GP_VECTOR); 3109 3110 if (sev_es_guest(svm->vcpu.kvm)) 3111 sev_es_init_vmcb(svm); 3112 } 3113 3114 void sev_es_vcpu_reset(struct vcpu_svm *svm) 3115 { 3116 /* 3117 * Set the GHCB MSR value as per the GHCB specification when emulating 3118 * vCPU RESET for an SEV-ES guest. 3119 */ 3120 set_ghcb_msr(svm, GHCB_MSR_SEV_INFO(GHCB_VERSION_MAX, 3121 GHCB_VERSION_MIN, 3122 sev_enc_bit)); 3123 } 3124 3125 void sev_es_prepare_switch_to_guest(struct sev_es_save_area *hostsa) 3126 { 3127 /* 3128 * All host state for SEV-ES guests is categorized into three swap types 3129 * based on how it is handled by hardware during a world switch: 3130 * 3131 * A: VMRUN: Host state saved in host save area 3132 * VMEXIT: Host state loaded from host save area 3133 * 3134 * B: VMRUN: Host state _NOT_ saved in host save area 3135 * VMEXIT: Host state loaded from host save area 3136 * 3137 * C: VMRUN: Host state _NOT_ saved in host save area 3138 * VMEXIT: Host state initialized to default(reset) values 3139 * 3140 * Manually save type-B state, i.e. state that is loaded by VMEXIT but 3141 * isn't saved by VMRUN, that isn't already saved by VMSAVE (performed 3142 * by common SVM code). 3143 */ 3144 hostsa->xcr0 = xgetbv(XCR_XFEATURE_ENABLED_MASK); 3145 hostsa->pkru = read_pkru(); 3146 hostsa->xss = host_xss; 3147 3148 /* 3149 * If DebugSwap is enabled, debug registers are loaded but NOT saved by 3150 * the CPU (Type-B). If DebugSwap is disabled/unsupported, the CPU both 3151 * saves and loads debug registers (Type-A). 3152 */ 3153 if (sev_es_debug_swap_enabled) { 3154 hostsa->dr0 = native_get_debugreg(0); 3155 hostsa->dr1 = native_get_debugreg(1); 3156 hostsa->dr2 = native_get_debugreg(2); 3157 hostsa->dr3 = native_get_debugreg(3); 3158 hostsa->dr0_addr_mask = amd_get_dr_addr_mask(0); 3159 hostsa->dr1_addr_mask = amd_get_dr_addr_mask(1); 3160 hostsa->dr2_addr_mask = amd_get_dr_addr_mask(2); 3161 hostsa->dr3_addr_mask = amd_get_dr_addr_mask(3); 3162 } 3163 } 3164 3165 void sev_vcpu_deliver_sipi_vector(struct kvm_vcpu *vcpu, u8 vector) 3166 { 3167 struct vcpu_svm *svm = to_svm(vcpu); 3168 3169 /* First SIPI: Use the values as initially set by the VMM */ 3170 if (!svm->sev_es.received_first_sipi) { 3171 svm->sev_es.received_first_sipi = true; 3172 return; 3173 } 3174 3175 /* 3176 * Subsequent SIPI: Return from an AP Reset Hold VMGEXIT, where 3177 * the guest will set the CS and RIP. Set SW_EXIT_INFO_2 to a 3178 * non-zero value. 3179 */ 3180 if (!svm->sev_es.ghcb) 3181 return; 3182 3183 ghcb_set_sw_exit_info_2(svm->sev_es.ghcb, 1); 3184 } 3185