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 = true; 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(int min_asid, int max_asid) 88 { 89 int ret, asid, error = 0; 90 91 /* Check if there are any ASIDs to reclaim before performing a flush */ 92 asid = find_next_bit(sev_reclaim_asid_bitmap, nr_asids, min_asid); 93 if (asid > max_asid) 94 return -EBUSY; 95 96 /* 97 * DEACTIVATE will clear the WBINVD indicator causing DF_FLUSH to fail, 98 * so it must be guarded. 99 */ 100 down_write(&sev_deactivate_lock); 101 102 wbinvd_on_all_cpus(); 103 ret = sev_guest_df_flush(&error); 104 105 up_write(&sev_deactivate_lock); 106 107 if (ret) 108 pr_err("SEV: DF_FLUSH failed, ret=%d, error=%#x\n", ret, error); 109 110 return ret; 111 } 112 113 static inline bool is_mirroring_enc_context(struct kvm *kvm) 114 { 115 return !!to_kvm_svm(kvm)->sev_info.enc_context_owner; 116 } 117 118 /* Must be called with the sev_bitmap_lock held */ 119 static bool __sev_recycle_asids(int min_asid, int max_asid) 120 { 121 if (sev_flush_asids(min_asid, max_asid)) 122 return false; 123 124 /* The flush process will flush all reclaimable SEV and SEV-ES ASIDs */ 125 bitmap_xor(sev_asid_bitmap, sev_asid_bitmap, sev_reclaim_asid_bitmap, 126 nr_asids); 127 bitmap_zero(sev_reclaim_asid_bitmap, nr_asids); 128 129 return true; 130 } 131 132 static int sev_misc_cg_try_charge(struct kvm_sev_info *sev) 133 { 134 enum misc_res_type type = sev->es_active ? MISC_CG_RES_SEV_ES : MISC_CG_RES_SEV; 135 return misc_cg_try_charge(type, sev->misc_cg, 1); 136 } 137 138 static void sev_misc_cg_uncharge(struct kvm_sev_info *sev) 139 { 140 enum misc_res_type type = sev->es_active ? MISC_CG_RES_SEV_ES : MISC_CG_RES_SEV; 141 misc_cg_uncharge(type, sev->misc_cg, 1); 142 } 143 144 static int sev_asid_new(struct kvm_sev_info *sev) 145 { 146 int asid, min_asid, max_asid, ret; 147 bool retry = true; 148 149 WARN_ON(sev->misc_cg); 150 sev->misc_cg = get_current_misc_cg(); 151 ret = sev_misc_cg_try_charge(sev); 152 if (ret) { 153 put_misc_cg(sev->misc_cg); 154 sev->misc_cg = NULL; 155 return ret; 156 } 157 158 mutex_lock(&sev_bitmap_lock); 159 160 /* 161 * SEV-enabled guests must use asid from min_sev_asid to max_sev_asid. 162 * SEV-ES-enabled guest can use from 1 to min_sev_asid - 1. 163 */ 164 min_asid = sev->es_active ? 1 : min_sev_asid; 165 max_asid = sev->es_active ? min_sev_asid - 1 : max_sev_asid; 166 again: 167 asid = find_next_zero_bit(sev_asid_bitmap, max_asid + 1, min_asid); 168 if (asid > max_asid) { 169 if (retry && __sev_recycle_asids(min_asid, max_asid)) { 170 retry = false; 171 goto again; 172 } 173 mutex_unlock(&sev_bitmap_lock); 174 ret = -EBUSY; 175 goto e_uncharge; 176 } 177 178 __set_bit(asid, sev_asid_bitmap); 179 180 mutex_unlock(&sev_bitmap_lock); 181 182 return asid; 183 e_uncharge: 184 sev_misc_cg_uncharge(sev); 185 put_misc_cg(sev->misc_cg); 186 sev->misc_cg = NULL; 187 return ret; 188 } 189 190 static int sev_get_asid(struct kvm *kvm) 191 { 192 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 193 194 return sev->asid; 195 } 196 197 static void sev_asid_free(struct kvm_sev_info *sev) 198 { 199 struct svm_cpu_data *sd; 200 int cpu; 201 202 mutex_lock(&sev_bitmap_lock); 203 204 __set_bit(sev->asid, sev_reclaim_asid_bitmap); 205 206 for_each_possible_cpu(cpu) { 207 sd = per_cpu_ptr(&svm_data, cpu); 208 sd->sev_vmcbs[sev->asid] = NULL; 209 } 210 211 mutex_unlock(&sev_bitmap_lock); 212 213 sev_misc_cg_uncharge(sev); 214 put_misc_cg(sev->misc_cg); 215 sev->misc_cg = NULL; 216 } 217 218 static void sev_decommission(unsigned int handle) 219 { 220 struct sev_data_decommission decommission; 221 222 if (!handle) 223 return; 224 225 decommission.handle = handle; 226 sev_guest_decommission(&decommission, NULL); 227 } 228 229 static void sev_unbind_asid(struct kvm *kvm, unsigned int handle) 230 { 231 struct sev_data_deactivate deactivate; 232 233 if (!handle) 234 return; 235 236 deactivate.handle = handle; 237 238 /* Guard DEACTIVATE against WBINVD/DF_FLUSH used in ASID recycling */ 239 down_read(&sev_deactivate_lock); 240 sev_guest_deactivate(&deactivate, NULL); 241 up_read(&sev_deactivate_lock); 242 243 sev_decommission(handle); 244 } 245 246 static int sev_guest_init(struct kvm *kvm, struct kvm_sev_cmd *argp) 247 { 248 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 249 struct sev_platform_init_args init_args = {0}; 250 int asid, ret; 251 252 if (kvm->created_vcpus) 253 return -EINVAL; 254 255 ret = -EBUSY; 256 if (unlikely(sev->active)) 257 return ret; 258 259 sev->active = true; 260 sev->es_active = argp->id == KVM_SEV_ES_INIT; 261 asid = sev_asid_new(sev); 262 if (asid < 0) 263 goto e_no_asid; 264 sev->asid = asid; 265 266 init_args.probe = false; 267 ret = sev_platform_init(&init_args); 268 if (ret) 269 goto e_free; 270 271 INIT_LIST_HEAD(&sev->regions_list); 272 INIT_LIST_HEAD(&sev->mirror_vms); 273 274 kvm_set_apicv_inhibit(kvm, APICV_INHIBIT_REASON_SEV); 275 276 return 0; 277 278 e_free: 279 argp->error = init_args.error; 280 sev_asid_free(sev); 281 sev->asid = 0; 282 e_no_asid: 283 sev->es_active = false; 284 sev->active = false; 285 return ret; 286 } 287 288 static int sev_bind_asid(struct kvm *kvm, unsigned int handle, int *error) 289 { 290 struct sev_data_activate activate; 291 int asid = sev_get_asid(kvm); 292 int ret; 293 294 /* activate ASID on the given handle */ 295 activate.handle = handle; 296 activate.asid = asid; 297 ret = sev_guest_activate(&activate, error); 298 299 return ret; 300 } 301 302 static int __sev_issue_cmd(int fd, int id, void *data, int *error) 303 { 304 struct fd f; 305 int ret; 306 307 f = fdget(fd); 308 if (!f.file) 309 return -EBADF; 310 311 ret = sev_issue_cmd_external_user(f.file, id, data, error); 312 313 fdput(f); 314 return ret; 315 } 316 317 static int sev_issue_cmd(struct kvm *kvm, int id, void *data, int *error) 318 { 319 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 320 321 return __sev_issue_cmd(sev->fd, id, data, error); 322 } 323 324 static int sev_launch_start(struct kvm *kvm, struct kvm_sev_cmd *argp) 325 { 326 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 327 struct sev_data_launch_start start; 328 struct kvm_sev_launch_start params; 329 void *dh_blob, *session_blob; 330 int *error = &argp->error; 331 int ret; 332 333 if (!sev_guest(kvm)) 334 return -ENOTTY; 335 336 if (copy_from_user(¶ms, (void __user *)(uintptr_t)argp->data, sizeof(params))) 337 return -EFAULT; 338 339 memset(&start, 0, sizeof(start)); 340 341 dh_blob = NULL; 342 if (params.dh_uaddr) { 343 dh_blob = psp_copy_user_blob(params.dh_uaddr, params.dh_len); 344 if (IS_ERR(dh_blob)) 345 return PTR_ERR(dh_blob); 346 347 start.dh_cert_address = __sme_set(__pa(dh_blob)); 348 start.dh_cert_len = params.dh_len; 349 } 350 351 session_blob = NULL; 352 if (params.session_uaddr) { 353 session_blob = psp_copy_user_blob(params.session_uaddr, params.session_len); 354 if (IS_ERR(session_blob)) { 355 ret = PTR_ERR(session_blob); 356 goto e_free_dh; 357 } 358 359 start.session_address = __sme_set(__pa(session_blob)); 360 start.session_len = params.session_len; 361 } 362 363 start.handle = params.handle; 364 start.policy = params.policy; 365 366 /* create memory encryption context */ 367 ret = __sev_issue_cmd(argp->sev_fd, SEV_CMD_LAUNCH_START, &start, error); 368 if (ret) 369 goto e_free_session; 370 371 /* Bind ASID to this guest */ 372 ret = sev_bind_asid(kvm, start.handle, error); 373 if (ret) { 374 sev_decommission(start.handle); 375 goto e_free_session; 376 } 377 378 /* return handle to userspace */ 379 params.handle = start.handle; 380 if (copy_to_user((void __user *)(uintptr_t)argp->data, ¶ms, sizeof(params))) { 381 sev_unbind_asid(kvm, start.handle); 382 ret = -EFAULT; 383 goto e_free_session; 384 } 385 386 sev->handle = start.handle; 387 sev->fd = argp->sev_fd; 388 389 e_free_session: 390 kfree(session_blob); 391 e_free_dh: 392 kfree(dh_blob); 393 return ret; 394 } 395 396 static struct page **sev_pin_memory(struct kvm *kvm, unsigned long uaddr, 397 unsigned long ulen, unsigned long *n, 398 int write) 399 { 400 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 401 unsigned long npages, size; 402 int npinned; 403 unsigned long locked, lock_limit; 404 struct page **pages; 405 unsigned long first, last; 406 int ret; 407 408 lockdep_assert_held(&kvm->lock); 409 410 if (ulen == 0 || uaddr + ulen < uaddr) 411 return ERR_PTR(-EINVAL); 412 413 /* Calculate number of pages. */ 414 first = (uaddr & PAGE_MASK) >> PAGE_SHIFT; 415 last = ((uaddr + ulen - 1) & PAGE_MASK) >> PAGE_SHIFT; 416 npages = (last - first + 1); 417 418 locked = sev->pages_locked + npages; 419 lock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT; 420 if (locked > lock_limit && !capable(CAP_IPC_LOCK)) { 421 pr_err("SEV: %lu locked pages exceed the lock limit of %lu.\n", locked, lock_limit); 422 return ERR_PTR(-ENOMEM); 423 } 424 425 if (WARN_ON_ONCE(npages > INT_MAX)) 426 return ERR_PTR(-EINVAL); 427 428 /* Avoid using vmalloc for smaller buffers. */ 429 size = npages * sizeof(struct page *); 430 if (size > PAGE_SIZE) 431 pages = __vmalloc(size, GFP_KERNEL_ACCOUNT | __GFP_ZERO); 432 else 433 pages = kmalloc(size, GFP_KERNEL_ACCOUNT); 434 435 if (!pages) 436 return ERR_PTR(-ENOMEM); 437 438 /* Pin the user virtual address. */ 439 npinned = pin_user_pages_fast(uaddr, npages, write ? FOLL_WRITE : 0, pages); 440 if (npinned != npages) { 441 pr_err("SEV: Failure locking %lu pages.\n", npages); 442 ret = -ENOMEM; 443 goto err; 444 } 445 446 *n = npages; 447 sev->pages_locked = locked; 448 449 return pages; 450 451 err: 452 if (npinned > 0) 453 unpin_user_pages(pages, npinned); 454 455 kvfree(pages); 456 return ERR_PTR(ret); 457 } 458 459 static void sev_unpin_memory(struct kvm *kvm, struct page **pages, 460 unsigned long npages) 461 { 462 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 463 464 unpin_user_pages(pages, npages); 465 kvfree(pages); 466 sev->pages_locked -= npages; 467 } 468 469 static void sev_clflush_pages(struct page *pages[], unsigned long npages) 470 { 471 uint8_t *page_virtual; 472 unsigned long i; 473 474 if (this_cpu_has(X86_FEATURE_SME_COHERENT) || npages == 0 || 475 pages == NULL) 476 return; 477 478 for (i = 0; i < npages; i++) { 479 page_virtual = kmap_local_page(pages[i]); 480 clflush_cache_range(page_virtual, PAGE_SIZE); 481 kunmap_local(page_virtual); 482 cond_resched(); 483 } 484 } 485 486 static unsigned long get_num_contig_pages(unsigned long idx, 487 struct page **inpages, unsigned long npages) 488 { 489 unsigned long paddr, next_paddr; 490 unsigned long i = idx + 1, pages = 1; 491 492 /* find the number of contiguous pages starting from idx */ 493 paddr = __sme_page_pa(inpages[idx]); 494 while (i < npages) { 495 next_paddr = __sme_page_pa(inpages[i++]); 496 if ((paddr + PAGE_SIZE) == next_paddr) { 497 pages++; 498 paddr = next_paddr; 499 continue; 500 } 501 break; 502 } 503 504 return pages; 505 } 506 507 static int sev_launch_update_data(struct kvm *kvm, struct kvm_sev_cmd *argp) 508 { 509 unsigned long vaddr, vaddr_end, next_vaddr, npages, pages, size, i; 510 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 511 struct kvm_sev_launch_update_data params; 512 struct sev_data_launch_update_data data; 513 struct page **inpages; 514 int ret; 515 516 if (!sev_guest(kvm)) 517 return -ENOTTY; 518 519 if (copy_from_user(¶ms, (void __user *)(uintptr_t)argp->data, sizeof(params))) 520 return -EFAULT; 521 522 vaddr = params.uaddr; 523 size = params.len; 524 vaddr_end = vaddr + size; 525 526 /* Lock the user memory. */ 527 inpages = sev_pin_memory(kvm, vaddr, size, &npages, 1); 528 if (IS_ERR(inpages)) 529 return PTR_ERR(inpages); 530 531 /* 532 * Flush (on non-coherent CPUs) before LAUNCH_UPDATE encrypts pages in 533 * place; the cache may contain the data that was written unencrypted. 534 */ 535 sev_clflush_pages(inpages, npages); 536 537 data.reserved = 0; 538 data.handle = sev->handle; 539 540 for (i = 0; vaddr < vaddr_end; vaddr = next_vaddr, i += pages) { 541 int offset, len; 542 543 /* 544 * If the user buffer is not page-aligned, calculate the offset 545 * within the page. 546 */ 547 offset = vaddr & (PAGE_SIZE - 1); 548 549 /* Calculate the number of pages that can be encrypted in one go. */ 550 pages = get_num_contig_pages(i, inpages, npages); 551 552 len = min_t(size_t, ((pages * PAGE_SIZE) - offset), size); 553 554 data.len = len; 555 data.address = __sme_page_pa(inpages[i]) + offset; 556 ret = sev_issue_cmd(kvm, SEV_CMD_LAUNCH_UPDATE_DATA, &data, &argp->error); 557 if (ret) 558 goto e_unpin; 559 560 size -= len; 561 next_vaddr = vaddr + len; 562 } 563 564 e_unpin: 565 /* content of memory is updated, mark pages dirty */ 566 for (i = 0; i < npages; i++) { 567 set_page_dirty_lock(inpages[i]); 568 mark_page_accessed(inpages[i]); 569 } 570 /* unlock the user pages */ 571 sev_unpin_memory(kvm, inpages, npages); 572 return ret; 573 } 574 575 static int sev_es_sync_vmsa(struct vcpu_svm *svm) 576 { 577 struct sev_es_save_area *save = svm->sev_es.vmsa; 578 579 /* Check some debug related fields before encrypting the VMSA */ 580 if (svm->vcpu.guest_debug || (svm->vmcb->save.dr7 & ~DR7_FIXED_1)) 581 return -EINVAL; 582 583 /* 584 * SEV-ES will use a VMSA that is pointed to by the VMCB, not 585 * the traditional VMSA that is part of the VMCB. Copy the 586 * traditional VMSA as it has been built so far (in prep 587 * for LAUNCH_UPDATE_VMSA) to be the initial SEV-ES state. 588 */ 589 memcpy(save, &svm->vmcb->save, sizeof(svm->vmcb->save)); 590 591 /* Sync registgers */ 592 save->rax = svm->vcpu.arch.regs[VCPU_REGS_RAX]; 593 save->rbx = svm->vcpu.arch.regs[VCPU_REGS_RBX]; 594 save->rcx = svm->vcpu.arch.regs[VCPU_REGS_RCX]; 595 save->rdx = svm->vcpu.arch.regs[VCPU_REGS_RDX]; 596 save->rsp = svm->vcpu.arch.regs[VCPU_REGS_RSP]; 597 save->rbp = svm->vcpu.arch.regs[VCPU_REGS_RBP]; 598 save->rsi = svm->vcpu.arch.regs[VCPU_REGS_RSI]; 599 save->rdi = svm->vcpu.arch.regs[VCPU_REGS_RDI]; 600 #ifdef CONFIG_X86_64 601 save->r8 = svm->vcpu.arch.regs[VCPU_REGS_R8]; 602 save->r9 = svm->vcpu.arch.regs[VCPU_REGS_R9]; 603 save->r10 = svm->vcpu.arch.regs[VCPU_REGS_R10]; 604 save->r11 = svm->vcpu.arch.regs[VCPU_REGS_R11]; 605 save->r12 = svm->vcpu.arch.regs[VCPU_REGS_R12]; 606 save->r13 = svm->vcpu.arch.regs[VCPU_REGS_R13]; 607 save->r14 = svm->vcpu.arch.regs[VCPU_REGS_R14]; 608 save->r15 = svm->vcpu.arch.regs[VCPU_REGS_R15]; 609 #endif 610 save->rip = svm->vcpu.arch.regs[VCPU_REGS_RIP]; 611 612 /* Sync some non-GPR registers before encrypting */ 613 save->xcr0 = svm->vcpu.arch.xcr0; 614 save->pkru = svm->vcpu.arch.pkru; 615 save->xss = svm->vcpu.arch.ia32_xss; 616 save->dr6 = svm->vcpu.arch.dr6; 617 618 if (sev_es_debug_swap_enabled) 619 save->sev_features |= SVM_SEV_FEAT_DEBUG_SWAP; 620 621 pr_debug("Virtual Machine Save Area (VMSA):\n"); 622 print_hex_dump_debug("", DUMP_PREFIX_NONE, 16, 1, save, sizeof(*save), false); 623 624 return 0; 625 } 626 627 static int __sev_launch_update_vmsa(struct kvm *kvm, struct kvm_vcpu *vcpu, 628 int *error) 629 { 630 struct sev_data_launch_update_vmsa vmsa; 631 struct vcpu_svm *svm = to_svm(vcpu); 632 int ret; 633 634 if (vcpu->guest_debug) { 635 pr_warn_once("KVM_SET_GUEST_DEBUG for SEV-ES guest is not supported"); 636 return -EINVAL; 637 } 638 639 /* Perform some pre-encryption checks against the VMSA */ 640 ret = sev_es_sync_vmsa(svm); 641 if (ret) 642 return ret; 643 644 /* 645 * The LAUNCH_UPDATE_VMSA command will perform in-place encryption of 646 * the VMSA memory content (i.e it will write the same memory region 647 * with the guest's key), so invalidate it first. 648 */ 649 clflush_cache_range(svm->sev_es.vmsa, PAGE_SIZE); 650 651 vmsa.reserved = 0; 652 vmsa.handle = to_kvm_svm(kvm)->sev_info.handle; 653 vmsa.address = __sme_pa(svm->sev_es.vmsa); 654 vmsa.len = PAGE_SIZE; 655 ret = sev_issue_cmd(kvm, SEV_CMD_LAUNCH_UPDATE_VMSA, &vmsa, error); 656 if (ret) 657 return ret; 658 659 vcpu->arch.guest_state_protected = true; 660 return 0; 661 } 662 663 static int sev_launch_update_vmsa(struct kvm *kvm, struct kvm_sev_cmd *argp) 664 { 665 struct kvm_vcpu *vcpu; 666 unsigned long i; 667 int ret; 668 669 if (!sev_es_guest(kvm)) 670 return -ENOTTY; 671 672 kvm_for_each_vcpu(i, vcpu, kvm) { 673 ret = mutex_lock_killable(&vcpu->mutex); 674 if (ret) 675 return ret; 676 677 ret = __sev_launch_update_vmsa(kvm, vcpu, &argp->error); 678 679 mutex_unlock(&vcpu->mutex); 680 if (ret) 681 return ret; 682 } 683 684 return 0; 685 } 686 687 static int sev_launch_measure(struct kvm *kvm, struct kvm_sev_cmd *argp) 688 { 689 void __user *measure = (void __user *)(uintptr_t)argp->data; 690 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 691 struct sev_data_launch_measure data; 692 struct kvm_sev_launch_measure params; 693 void __user *p = NULL; 694 void *blob = NULL; 695 int ret; 696 697 if (!sev_guest(kvm)) 698 return -ENOTTY; 699 700 if (copy_from_user(¶ms, measure, sizeof(params))) 701 return -EFAULT; 702 703 memset(&data, 0, sizeof(data)); 704 705 /* User wants to query the blob length */ 706 if (!params.len) 707 goto cmd; 708 709 p = (void __user *)(uintptr_t)params.uaddr; 710 if (p) { 711 if (params.len > SEV_FW_BLOB_MAX_SIZE) 712 return -EINVAL; 713 714 blob = kzalloc(params.len, GFP_KERNEL_ACCOUNT); 715 if (!blob) 716 return -ENOMEM; 717 718 data.address = __psp_pa(blob); 719 data.len = params.len; 720 } 721 722 cmd: 723 data.handle = sev->handle; 724 ret = sev_issue_cmd(kvm, SEV_CMD_LAUNCH_MEASURE, &data, &argp->error); 725 726 /* 727 * If we query the session length, FW responded with expected data. 728 */ 729 if (!params.len) 730 goto done; 731 732 if (ret) 733 goto e_free_blob; 734 735 if (blob) { 736 if (copy_to_user(p, blob, params.len)) 737 ret = -EFAULT; 738 } 739 740 done: 741 params.len = data.len; 742 if (copy_to_user(measure, ¶ms, sizeof(params))) 743 ret = -EFAULT; 744 e_free_blob: 745 kfree(blob); 746 return ret; 747 } 748 749 static int sev_launch_finish(struct kvm *kvm, struct kvm_sev_cmd *argp) 750 { 751 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 752 struct sev_data_launch_finish data; 753 754 if (!sev_guest(kvm)) 755 return -ENOTTY; 756 757 data.handle = sev->handle; 758 return sev_issue_cmd(kvm, SEV_CMD_LAUNCH_FINISH, &data, &argp->error); 759 } 760 761 static int sev_guest_status(struct kvm *kvm, struct kvm_sev_cmd *argp) 762 { 763 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 764 struct kvm_sev_guest_status params; 765 struct sev_data_guest_status data; 766 int ret; 767 768 if (!sev_guest(kvm)) 769 return -ENOTTY; 770 771 memset(&data, 0, sizeof(data)); 772 773 data.handle = sev->handle; 774 ret = sev_issue_cmd(kvm, SEV_CMD_GUEST_STATUS, &data, &argp->error); 775 if (ret) 776 return ret; 777 778 params.policy = data.policy; 779 params.state = data.state; 780 params.handle = data.handle; 781 782 if (copy_to_user((void __user *)(uintptr_t)argp->data, ¶ms, sizeof(params))) 783 ret = -EFAULT; 784 785 return ret; 786 } 787 788 static int __sev_issue_dbg_cmd(struct kvm *kvm, unsigned long src, 789 unsigned long dst, int size, 790 int *error, bool enc) 791 { 792 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 793 struct sev_data_dbg data; 794 795 data.reserved = 0; 796 data.handle = sev->handle; 797 data.dst_addr = dst; 798 data.src_addr = src; 799 data.len = size; 800 801 return sev_issue_cmd(kvm, 802 enc ? SEV_CMD_DBG_ENCRYPT : SEV_CMD_DBG_DECRYPT, 803 &data, error); 804 } 805 806 static int __sev_dbg_decrypt(struct kvm *kvm, unsigned long src_paddr, 807 unsigned long dst_paddr, int sz, int *err) 808 { 809 int offset; 810 811 /* 812 * Its safe to read more than we are asked, caller should ensure that 813 * destination has enough space. 814 */ 815 offset = src_paddr & 15; 816 src_paddr = round_down(src_paddr, 16); 817 sz = round_up(sz + offset, 16); 818 819 return __sev_issue_dbg_cmd(kvm, src_paddr, dst_paddr, sz, err, false); 820 } 821 822 static int __sev_dbg_decrypt_user(struct kvm *kvm, unsigned long paddr, 823 void __user *dst_uaddr, 824 unsigned long dst_paddr, 825 int size, int *err) 826 { 827 struct page *tpage = NULL; 828 int ret, offset; 829 830 /* if inputs are not 16-byte then use intermediate buffer */ 831 if (!IS_ALIGNED(dst_paddr, 16) || 832 !IS_ALIGNED(paddr, 16) || 833 !IS_ALIGNED(size, 16)) { 834 tpage = (void *)alloc_page(GFP_KERNEL_ACCOUNT | __GFP_ZERO); 835 if (!tpage) 836 return -ENOMEM; 837 838 dst_paddr = __sme_page_pa(tpage); 839 } 840 841 ret = __sev_dbg_decrypt(kvm, paddr, dst_paddr, size, err); 842 if (ret) 843 goto e_free; 844 845 if (tpage) { 846 offset = paddr & 15; 847 if (copy_to_user(dst_uaddr, page_address(tpage) + offset, size)) 848 ret = -EFAULT; 849 } 850 851 e_free: 852 if (tpage) 853 __free_page(tpage); 854 855 return ret; 856 } 857 858 static int __sev_dbg_encrypt_user(struct kvm *kvm, unsigned long paddr, 859 void __user *vaddr, 860 unsigned long dst_paddr, 861 void __user *dst_vaddr, 862 int size, int *error) 863 { 864 struct page *src_tpage = NULL; 865 struct page *dst_tpage = NULL; 866 int ret, len = size; 867 868 /* If source buffer is not aligned then use an intermediate buffer */ 869 if (!IS_ALIGNED((unsigned long)vaddr, 16)) { 870 src_tpage = alloc_page(GFP_KERNEL_ACCOUNT); 871 if (!src_tpage) 872 return -ENOMEM; 873 874 if (copy_from_user(page_address(src_tpage), vaddr, size)) { 875 __free_page(src_tpage); 876 return -EFAULT; 877 } 878 879 paddr = __sme_page_pa(src_tpage); 880 } 881 882 /* 883 * If destination buffer or length is not aligned then do read-modify-write: 884 * - decrypt destination in an intermediate buffer 885 * - copy the source buffer in an intermediate buffer 886 * - use the intermediate buffer as source buffer 887 */ 888 if (!IS_ALIGNED((unsigned long)dst_vaddr, 16) || !IS_ALIGNED(size, 16)) { 889 int dst_offset; 890 891 dst_tpage = alloc_page(GFP_KERNEL_ACCOUNT); 892 if (!dst_tpage) { 893 ret = -ENOMEM; 894 goto e_free; 895 } 896 897 ret = __sev_dbg_decrypt(kvm, dst_paddr, 898 __sme_page_pa(dst_tpage), size, error); 899 if (ret) 900 goto e_free; 901 902 /* 903 * If source is kernel buffer then use memcpy() otherwise 904 * copy_from_user(). 905 */ 906 dst_offset = dst_paddr & 15; 907 908 if (src_tpage) 909 memcpy(page_address(dst_tpage) + dst_offset, 910 page_address(src_tpage), size); 911 else { 912 if (copy_from_user(page_address(dst_tpage) + dst_offset, 913 vaddr, size)) { 914 ret = -EFAULT; 915 goto e_free; 916 } 917 } 918 919 paddr = __sme_page_pa(dst_tpage); 920 dst_paddr = round_down(dst_paddr, 16); 921 len = round_up(size, 16); 922 } 923 924 ret = __sev_issue_dbg_cmd(kvm, paddr, dst_paddr, len, error, true); 925 926 e_free: 927 if (src_tpage) 928 __free_page(src_tpage); 929 if (dst_tpage) 930 __free_page(dst_tpage); 931 return ret; 932 } 933 934 static int sev_dbg_crypt(struct kvm *kvm, struct kvm_sev_cmd *argp, bool dec) 935 { 936 unsigned long vaddr, vaddr_end, next_vaddr; 937 unsigned long dst_vaddr; 938 struct page **src_p, **dst_p; 939 struct kvm_sev_dbg debug; 940 unsigned long n; 941 unsigned int size; 942 int ret; 943 944 if (!sev_guest(kvm)) 945 return -ENOTTY; 946 947 if (copy_from_user(&debug, (void __user *)(uintptr_t)argp->data, sizeof(debug))) 948 return -EFAULT; 949 950 if (!debug.len || debug.src_uaddr + debug.len < debug.src_uaddr) 951 return -EINVAL; 952 if (!debug.dst_uaddr) 953 return -EINVAL; 954 955 vaddr = debug.src_uaddr; 956 size = debug.len; 957 vaddr_end = vaddr + size; 958 dst_vaddr = debug.dst_uaddr; 959 960 for (; vaddr < vaddr_end; vaddr = next_vaddr) { 961 int len, s_off, d_off; 962 963 /* lock userspace source and destination page */ 964 src_p = sev_pin_memory(kvm, vaddr & PAGE_MASK, PAGE_SIZE, &n, 0); 965 if (IS_ERR(src_p)) 966 return PTR_ERR(src_p); 967 968 dst_p = sev_pin_memory(kvm, dst_vaddr & PAGE_MASK, PAGE_SIZE, &n, 1); 969 if (IS_ERR(dst_p)) { 970 sev_unpin_memory(kvm, src_p, n); 971 return PTR_ERR(dst_p); 972 } 973 974 /* 975 * Flush (on non-coherent CPUs) before DBG_{DE,EN}CRYPT read or modify 976 * the pages; flush the destination too so that future accesses do not 977 * see stale data. 978 */ 979 sev_clflush_pages(src_p, 1); 980 sev_clflush_pages(dst_p, 1); 981 982 /* 983 * Since user buffer may not be page aligned, calculate the 984 * offset within the page. 985 */ 986 s_off = vaddr & ~PAGE_MASK; 987 d_off = dst_vaddr & ~PAGE_MASK; 988 len = min_t(size_t, (PAGE_SIZE - s_off), size); 989 990 if (dec) 991 ret = __sev_dbg_decrypt_user(kvm, 992 __sme_page_pa(src_p[0]) + s_off, 993 (void __user *)dst_vaddr, 994 __sme_page_pa(dst_p[0]) + d_off, 995 len, &argp->error); 996 else 997 ret = __sev_dbg_encrypt_user(kvm, 998 __sme_page_pa(src_p[0]) + s_off, 999 (void __user *)vaddr, 1000 __sme_page_pa(dst_p[0]) + d_off, 1001 (void __user *)dst_vaddr, 1002 len, &argp->error); 1003 1004 sev_unpin_memory(kvm, src_p, n); 1005 sev_unpin_memory(kvm, dst_p, n); 1006 1007 if (ret) 1008 goto err; 1009 1010 next_vaddr = vaddr + len; 1011 dst_vaddr = dst_vaddr + len; 1012 size -= len; 1013 } 1014 err: 1015 return ret; 1016 } 1017 1018 static int sev_launch_secret(struct kvm *kvm, struct kvm_sev_cmd *argp) 1019 { 1020 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 1021 struct sev_data_launch_secret data; 1022 struct kvm_sev_launch_secret params; 1023 struct page **pages; 1024 void *blob, *hdr; 1025 unsigned long n, i; 1026 int ret, offset; 1027 1028 if (!sev_guest(kvm)) 1029 return -ENOTTY; 1030 1031 if (copy_from_user(¶ms, (void __user *)(uintptr_t)argp->data, sizeof(params))) 1032 return -EFAULT; 1033 1034 pages = sev_pin_memory(kvm, params.guest_uaddr, params.guest_len, &n, 1); 1035 if (IS_ERR(pages)) 1036 return PTR_ERR(pages); 1037 1038 /* 1039 * Flush (on non-coherent CPUs) before LAUNCH_SECRET encrypts pages in 1040 * place; the cache may contain the data that was written unencrypted. 1041 */ 1042 sev_clflush_pages(pages, n); 1043 1044 /* 1045 * The secret must be copied into contiguous memory region, lets verify 1046 * that userspace memory pages are contiguous before we issue command. 1047 */ 1048 if (get_num_contig_pages(0, pages, n) != n) { 1049 ret = -EINVAL; 1050 goto e_unpin_memory; 1051 } 1052 1053 memset(&data, 0, sizeof(data)); 1054 1055 offset = params.guest_uaddr & (PAGE_SIZE - 1); 1056 data.guest_address = __sme_page_pa(pages[0]) + offset; 1057 data.guest_len = params.guest_len; 1058 1059 blob = psp_copy_user_blob(params.trans_uaddr, params.trans_len); 1060 if (IS_ERR(blob)) { 1061 ret = PTR_ERR(blob); 1062 goto e_unpin_memory; 1063 } 1064 1065 data.trans_address = __psp_pa(blob); 1066 data.trans_len = params.trans_len; 1067 1068 hdr = psp_copy_user_blob(params.hdr_uaddr, params.hdr_len); 1069 if (IS_ERR(hdr)) { 1070 ret = PTR_ERR(hdr); 1071 goto e_free_blob; 1072 } 1073 data.hdr_address = __psp_pa(hdr); 1074 data.hdr_len = params.hdr_len; 1075 1076 data.handle = sev->handle; 1077 ret = sev_issue_cmd(kvm, SEV_CMD_LAUNCH_UPDATE_SECRET, &data, &argp->error); 1078 1079 kfree(hdr); 1080 1081 e_free_blob: 1082 kfree(blob); 1083 e_unpin_memory: 1084 /* content of memory is updated, mark pages dirty */ 1085 for (i = 0; i < n; i++) { 1086 set_page_dirty_lock(pages[i]); 1087 mark_page_accessed(pages[i]); 1088 } 1089 sev_unpin_memory(kvm, pages, n); 1090 return ret; 1091 } 1092 1093 static int sev_get_attestation_report(struct kvm *kvm, struct kvm_sev_cmd *argp) 1094 { 1095 void __user *report = (void __user *)(uintptr_t)argp->data; 1096 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 1097 struct sev_data_attestation_report data; 1098 struct kvm_sev_attestation_report params; 1099 void __user *p; 1100 void *blob = NULL; 1101 int ret; 1102 1103 if (!sev_guest(kvm)) 1104 return -ENOTTY; 1105 1106 if (copy_from_user(¶ms, (void __user *)(uintptr_t)argp->data, sizeof(params))) 1107 return -EFAULT; 1108 1109 memset(&data, 0, sizeof(data)); 1110 1111 /* User wants to query the blob length */ 1112 if (!params.len) 1113 goto cmd; 1114 1115 p = (void __user *)(uintptr_t)params.uaddr; 1116 if (p) { 1117 if (params.len > SEV_FW_BLOB_MAX_SIZE) 1118 return -EINVAL; 1119 1120 blob = kzalloc(params.len, GFP_KERNEL_ACCOUNT); 1121 if (!blob) 1122 return -ENOMEM; 1123 1124 data.address = __psp_pa(blob); 1125 data.len = params.len; 1126 memcpy(data.mnonce, params.mnonce, sizeof(params.mnonce)); 1127 } 1128 cmd: 1129 data.handle = sev->handle; 1130 ret = sev_issue_cmd(kvm, SEV_CMD_ATTESTATION_REPORT, &data, &argp->error); 1131 /* 1132 * If we query the session length, FW responded with expected data. 1133 */ 1134 if (!params.len) 1135 goto done; 1136 1137 if (ret) 1138 goto e_free_blob; 1139 1140 if (blob) { 1141 if (copy_to_user(p, blob, params.len)) 1142 ret = -EFAULT; 1143 } 1144 1145 done: 1146 params.len = data.len; 1147 if (copy_to_user(report, ¶ms, sizeof(params))) 1148 ret = -EFAULT; 1149 e_free_blob: 1150 kfree(blob); 1151 return ret; 1152 } 1153 1154 /* Userspace wants to query session length. */ 1155 static int 1156 __sev_send_start_query_session_length(struct kvm *kvm, struct kvm_sev_cmd *argp, 1157 struct kvm_sev_send_start *params) 1158 { 1159 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 1160 struct sev_data_send_start data; 1161 int ret; 1162 1163 memset(&data, 0, sizeof(data)); 1164 data.handle = sev->handle; 1165 ret = sev_issue_cmd(kvm, SEV_CMD_SEND_START, &data, &argp->error); 1166 1167 params->session_len = data.session_len; 1168 if (copy_to_user((void __user *)(uintptr_t)argp->data, params, 1169 sizeof(struct kvm_sev_send_start))) 1170 ret = -EFAULT; 1171 1172 return ret; 1173 } 1174 1175 static int sev_send_start(struct kvm *kvm, struct kvm_sev_cmd *argp) 1176 { 1177 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 1178 struct sev_data_send_start data; 1179 struct kvm_sev_send_start params; 1180 void *amd_certs, *session_data; 1181 void *pdh_cert, *plat_certs; 1182 int ret; 1183 1184 if (!sev_guest(kvm)) 1185 return -ENOTTY; 1186 1187 if (copy_from_user(¶ms, (void __user *)(uintptr_t)argp->data, 1188 sizeof(struct kvm_sev_send_start))) 1189 return -EFAULT; 1190 1191 /* if session_len is zero, userspace wants to query the session length */ 1192 if (!params.session_len) 1193 return __sev_send_start_query_session_length(kvm, argp, 1194 ¶ms); 1195 1196 /* some sanity checks */ 1197 if (!params.pdh_cert_uaddr || !params.pdh_cert_len || 1198 !params.session_uaddr || params.session_len > SEV_FW_BLOB_MAX_SIZE) 1199 return -EINVAL; 1200 1201 /* allocate the memory to hold the session data blob */ 1202 session_data = kzalloc(params.session_len, GFP_KERNEL_ACCOUNT); 1203 if (!session_data) 1204 return -ENOMEM; 1205 1206 /* copy the certificate blobs from userspace */ 1207 pdh_cert = psp_copy_user_blob(params.pdh_cert_uaddr, 1208 params.pdh_cert_len); 1209 if (IS_ERR(pdh_cert)) { 1210 ret = PTR_ERR(pdh_cert); 1211 goto e_free_session; 1212 } 1213 1214 plat_certs = psp_copy_user_blob(params.plat_certs_uaddr, 1215 params.plat_certs_len); 1216 if (IS_ERR(plat_certs)) { 1217 ret = PTR_ERR(plat_certs); 1218 goto e_free_pdh; 1219 } 1220 1221 amd_certs = psp_copy_user_blob(params.amd_certs_uaddr, 1222 params.amd_certs_len); 1223 if (IS_ERR(amd_certs)) { 1224 ret = PTR_ERR(amd_certs); 1225 goto e_free_plat_cert; 1226 } 1227 1228 /* populate the FW SEND_START field with system physical address */ 1229 memset(&data, 0, sizeof(data)); 1230 data.pdh_cert_address = __psp_pa(pdh_cert); 1231 data.pdh_cert_len = params.pdh_cert_len; 1232 data.plat_certs_address = __psp_pa(plat_certs); 1233 data.plat_certs_len = params.plat_certs_len; 1234 data.amd_certs_address = __psp_pa(amd_certs); 1235 data.amd_certs_len = params.amd_certs_len; 1236 data.session_address = __psp_pa(session_data); 1237 data.session_len = params.session_len; 1238 data.handle = sev->handle; 1239 1240 ret = sev_issue_cmd(kvm, SEV_CMD_SEND_START, &data, &argp->error); 1241 1242 if (!ret && copy_to_user((void __user *)(uintptr_t)params.session_uaddr, 1243 session_data, params.session_len)) { 1244 ret = -EFAULT; 1245 goto e_free_amd_cert; 1246 } 1247 1248 params.policy = data.policy; 1249 params.session_len = data.session_len; 1250 if (copy_to_user((void __user *)(uintptr_t)argp->data, ¶ms, 1251 sizeof(struct kvm_sev_send_start))) 1252 ret = -EFAULT; 1253 1254 e_free_amd_cert: 1255 kfree(amd_certs); 1256 e_free_plat_cert: 1257 kfree(plat_certs); 1258 e_free_pdh: 1259 kfree(pdh_cert); 1260 e_free_session: 1261 kfree(session_data); 1262 return ret; 1263 } 1264 1265 /* Userspace wants to query either header or trans length. */ 1266 static int 1267 __sev_send_update_data_query_lengths(struct kvm *kvm, struct kvm_sev_cmd *argp, 1268 struct kvm_sev_send_update_data *params) 1269 { 1270 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 1271 struct sev_data_send_update_data data; 1272 int ret; 1273 1274 memset(&data, 0, sizeof(data)); 1275 data.handle = sev->handle; 1276 ret = sev_issue_cmd(kvm, SEV_CMD_SEND_UPDATE_DATA, &data, &argp->error); 1277 1278 params->hdr_len = data.hdr_len; 1279 params->trans_len = data.trans_len; 1280 1281 if (copy_to_user((void __user *)(uintptr_t)argp->data, params, 1282 sizeof(struct kvm_sev_send_update_data))) 1283 ret = -EFAULT; 1284 1285 return ret; 1286 } 1287 1288 static int sev_send_update_data(struct kvm *kvm, struct kvm_sev_cmd *argp) 1289 { 1290 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 1291 struct sev_data_send_update_data data; 1292 struct kvm_sev_send_update_data params; 1293 void *hdr, *trans_data; 1294 struct page **guest_page; 1295 unsigned long n; 1296 int ret, offset; 1297 1298 if (!sev_guest(kvm)) 1299 return -ENOTTY; 1300 1301 if (copy_from_user(¶ms, (void __user *)(uintptr_t)argp->data, 1302 sizeof(struct kvm_sev_send_update_data))) 1303 return -EFAULT; 1304 1305 /* userspace wants to query either header or trans length */ 1306 if (!params.trans_len || !params.hdr_len) 1307 return __sev_send_update_data_query_lengths(kvm, argp, ¶ms); 1308 1309 if (!params.trans_uaddr || !params.guest_uaddr || 1310 !params.guest_len || !params.hdr_uaddr) 1311 return -EINVAL; 1312 1313 /* Check if we are crossing the page boundary */ 1314 offset = params.guest_uaddr & (PAGE_SIZE - 1); 1315 if (params.guest_len > PAGE_SIZE || (params.guest_len + offset) > PAGE_SIZE) 1316 return -EINVAL; 1317 1318 /* Pin guest memory */ 1319 guest_page = sev_pin_memory(kvm, params.guest_uaddr & PAGE_MASK, 1320 PAGE_SIZE, &n, 0); 1321 if (IS_ERR(guest_page)) 1322 return PTR_ERR(guest_page); 1323 1324 /* allocate memory for header and transport buffer */ 1325 ret = -ENOMEM; 1326 hdr = kzalloc(params.hdr_len, GFP_KERNEL_ACCOUNT); 1327 if (!hdr) 1328 goto e_unpin; 1329 1330 trans_data = kzalloc(params.trans_len, GFP_KERNEL_ACCOUNT); 1331 if (!trans_data) 1332 goto e_free_hdr; 1333 1334 memset(&data, 0, sizeof(data)); 1335 data.hdr_address = __psp_pa(hdr); 1336 data.hdr_len = params.hdr_len; 1337 data.trans_address = __psp_pa(trans_data); 1338 data.trans_len = params.trans_len; 1339 1340 /* The SEND_UPDATE_DATA command requires C-bit to be always set. */ 1341 data.guest_address = (page_to_pfn(guest_page[0]) << PAGE_SHIFT) + offset; 1342 data.guest_address |= sev_me_mask; 1343 data.guest_len = params.guest_len; 1344 data.handle = sev->handle; 1345 1346 ret = sev_issue_cmd(kvm, SEV_CMD_SEND_UPDATE_DATA, &data, &argp->error); 1347 1348 if (ret) 1349 goto e_free_trans_data; 1350 1351 /* copy transport buffer to user space */ 1352 if (copy_to_user((void __user *)(uintptr_t)params.trans_uaddr, 1353 trans_data, params.trans_len)) { 1354 ret = -EFAULT; 1355 goto e_free_trans_data; 1356 } 1357 1358 /* Copy packet header to userspace. */ 1359 if (copy_to_user((void __user *)(uintptr_t)params.hdr_uaddr, hdr, 1360 params.hdr_len)) 1361 ret = -EFAULT; 1362 1363 e_free_trans_data: 1364 kfree(trans_data); 1365 e_free_hdr: 1366 kfree(hdr); 1367 e_unpin: 1368 sev_unpin_memory(kvm, guest_page, n); 1369 1370 return ret; 1371 } 1372 1373 static int sev_send_finish(struct kvm *kvm, struct kvm_sev_cmd *argp) 1374 { 1375 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 1376 struct sev_data_send_finish data; 1377 1378 if (!sev_guest(kvm)) 1379 return -ENOTTY; 1380 1381 data.handle = sev->handle; 1382 return sev_issue_cmd(kvm, SEV_CMD_SEND_FINISH, &data, &argp->error); 1383 } 1384 1385 static int sev_send_cancel(struct kvm *kvm, struct kvm_sev_cmd *argp) 1386 { 1387 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 1388 struct sev_data_send_cancel data; 1389 1390 if (!sev_guest(kvm)) 1391 return -ENOTTY; 1392 1393 data.handle = sev->handle; 1394 return sev_issue_cmd(kvm, SEV_CMD_SEND_CANCEL, &data, &argp->error); 1395 } 1396 1397 static int sev_receive_start(struct kvm *kvm, struct kvm_sev_cmd *argp) 1398 { 1399 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 1400 struct sev_data_receive_start start; 1401 struct kvm_sev_receive_start params; 1402 int *error = &argp->error; 1403 void *session_data; 1404 void *pdh_data; 1405 int ret; 1406 1407 if (!sev_guest(kvm)) 1408 return -ENOTTY; 1409 1410 /* Get parameter from the userspace */ 1411 if (copy_from_user(¶ms, (void __user *)(uintptr_t)argp->data, 1412 sizeof(struct kvm_sev_receive_start))) 1413 return -EFAULT; 1414 1415 /* some sanity checks */ 1416 if (!params.pdh_uaddr || !params.pdh_len || 1417 !params.session_uaddr || !params.session_len) 1418 return -EINVAL; 1419 1420 pdh_data = psp_copy_user_blob(params.pdh_uaddr, params.pdh_len); 1421 if (IS_ERR(pdh_data)) 1422 return PTR_ERR(pdh_data); 1423 1424 session_data = psp_copy_user_blob(params.session_uaddr, 1425 params.session_len); 1426 if (IS_ERR(session_data)) { 1427 ret = PTR_ERR(session_data); 1428 goto e_free_pdh; 1429 } 1430 1431 memset(&start, 0, sizeof(start)); 1432 start.handle = params.handle; 1433 start.policy = params.policy; 1434 start.pdh_cert_address = __psp_pa(pdh_data); 1435 start.pdh_cert_len = params.pdh_len; 1436 start.session_address = __psp_pa(session_data); 1437 start.session_len = params.session_len; 1438 1439 /* create memory encryption context */ 1440 ret = __sev_issue_cmd(argp->sev_fd, SEV_CMD_RECEIVE_START, &start, 1441 error); 1442 if (ret) 1443 goto e_free_session; 1444 1445 /* Bind ASID to this guest */ 1446 ret = sev_bind_asid(kvm, start.handle, error); 1447 if (ret) { 1448 sev_decommission(start.handle); 1449 goto e_free_session; 1450 } 1451 1452 params.handle = start.handle; 1453 if (copy_to_user((void __user *)(uintptr_t)argp->data, 1454 ¶ms, sizeof(struct kvm_sev_receive_start))) { 1455 ret = -EFAULT; 1456 sev_unbind_asid(kvm, start.handle); 1457 goto e_free_session; 1458 } 1459 1460 sev->handle = start.handle; 1461 sev->fd = argp->sev_fd; 1462 1463 e_free_session: 1464 kfree(session_data); 1465 e_free_pdh: 1466 kfree(pdh_data); 1467 1468 return ret; 1469 } 1470 1471 static int sev_receive_update_data(struct kvm *kvm, struct kvm_sev_cmd *argp) 1472 { 1473 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 1474 struct kvm_sev_receive_update_data params; 1475 struct sev_data_receive_update_data data; 1476 void *hdr = NULL, *trans = NULL; 1477 struct page **guest_page; 1478 unsigned long n; 1479 int ret, offset; 1480 1481 if (!sev_guest(kvm)) 1482 return -EINVAL; 1483 1484 if (copy_from_user(¶ms, (void __user *)(uintptr_t)argp->data, 1485 sizeof(struct kvm_sev_receive_update_data))) 1486 return -EFAULT; 1487 1488 if (!params.hdr_uaddr || !params.hdr_len || 1489 !params.guest_uaddr || !params.guest_len || 1490 !params.trans_uaddr || !params.trans_len) 1491 return -EINVAL; 1492 1493 /* Check if we are crossing the page boundary */ 1494 offset = params.guest_uaddr & (PAGE_SIZE - 1); 1495 if (params.guest_len > PAGE_SIZE || (params.guest_len + offset) > PAGE_SIZE) 1496 return -EINVAL; 1497 1498 hdr = psp_copy_user_blob(params.hdr_uaddr, params.hdr_len); 1499 if (IS_ERR(hdr)) 1500 return PTR_ERR(hdr); 1501 1502 trans = psp_copy_user_blob(params.trans_uaddr, params.trans_len); 1503 if (IS_ERR(trans)) { 1504 ret = PTR_ERR(trans); 1505 goto e_free_hdr; 1506 } 1507 1508 memset(&data, 0, sizeof(data)); 1509 data.hdr_address = __psp_pa(hdr); 1510 data.hdr_len = params.hdr_len; 1511 data.trans_address = __psp_pa(trans); 1512 data.trans_len = params.trans_len; 1513 1514 /* Pin guest memory */ 1515 guest_page = sev_pin_memory(kvm, params.guest_uaddr & PAGE_MASK, 1516 PAGE_SIZE, &n, 1); 1517 if (IS_ERR(guest_page)) { 1518 ret = PTR_ERR(guest_page); 1519 goto e_free_trans; 1520 } 1521 1522 /* 1523 * Flush (on non-coherent CPUs) before RECEIVE_UPDATE_DATA, the PSP 1524 * encrypts the written data with the guest's key, and the cache may 1525 * contain dirty, unencrypted data. 1526 */ 1527 sev_clflush_pages(guest_page, n); 1528 1529 /* The RECEIVE_UPDATE_DATA command requires C-bit to be always set. */ 1530 data.guest_address = (page_to_pfn(guest_page[0]) << PAGE_SHIFT) + offset; 1531 data.guest_address |= sev_me_mask; 1532 data.guest_len = params.guest_len; 1533 data.handle = sev->handle; 1534 1535 ret = sev_issue_cmd(kvm, SEV_CMD_RECEIVE_UPDATE_DATA, &data, 1536 &argp->error); 1537 1538 sev_unpin_memory(kvm, guest_page, n); 1539 1540 e_free_trans: 1541 kfree(trans); 1542 e_free_hdr: 1543 kfree(hdr); 1544 1545 return ret; 1546 } 1547 1548 static int sev_receive_finish(struct kvm *kvm, struct kvm_sev_cmd *argp) 1549 { 1550 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 1551 struct sev_data_receive_finish data; 1552 1553 if (!sev_guest(kvm)) 1554 return -ENOTTY; 1555 1556 data.handle = sev->handle; 1557 return sev_issue_cmd(kvm, SEV_CMD_RECEIVE_FINISH, &data, &argp->error); 1558 } 1559 1560 static bool is_cmd_allowed_from_mirror(u32 cmd_id) 1561 { 1562 /* 1563 * Allow mirrors VM to call KVM_SEV_LAUNCH_UPDATE_VMSA to enable SEV-ES 1564 * active mirror VMs. Also allow the debugging and status commands. 1565 */ 1566 if (cmd_id == KVM_SEV_LAUNCH_UPDATE_VMSA || 1567 cmd_id == KVM_SEV_GUEST_STATUS || cmd_id == KVM_SEV_DBG_DECRYPT || 1568 cmd_id == KVM_SEV_DBG_ENCRYPT) 1569 return true; 1570 1571 return false; 1572 } 1573 1574 static int sev_lock_two_vms(struct kvm *dst_kvm, struct kvm *src_kvm) 1575 { 1576 struct kvm_sev_info *dst_sev = &to_kvm_svm(dst_kvm)->sev_info; 1577 struct kvm_sev_info *src_sev = &to_kvm_svm(src_kvm)->sev_info; 1578 int r = -EBUSY; 1579 1580 if (dst_kvm == src_kvm) 1581 return -EINVAL; 1582 1583 /* 1584 * Bail if these VMs are already involved in a migration to avoid 1585 * deadlock between two VMs trying to migrate to/from each other. 1586 */ 1587 if (atomic_cmpxchg_acquire(&dst_sev->migration_in_progress, 0, 1)) 1588 return -EBUSY; 1589 1590 if (atomic_cmpxchg_acquire(&src_sev->migration_in_progress, 0, 1)) 1591 goto release_dst; 1592 1593 r = -EINTR; 1594 if (mutex_lock_killable(&dst_kvm->lock)) 1595 goto release_src; 1596 if (mutex_lock_killable_nested(&src_kvm->lock, SINGLE_DEPTH_NESTING)) 1597 goto unlock_dst; 1598 return 0; 1599 1600 unlock_dst: 1601 mutex_unlock(&dst_kvm->lock); 1602 release_src: 1603 atomic_set_release(&src_sev->migration_in_progress, 0); 1604 release_dst: 1605 atomic_set_release(&dst_sev->migration_in_progress, 0); 1606 return r; 1607 } 1608 1609 static void sev_unlock_two_vms(struct kvm *dst_kvm, struct kvm *src_kvm) 1610 { 1611 struct kvm_sev_info *dst_sev = &to_kvm_svm(dst_kvm)->sev_info; 1612 struct kvm_sev_info *src_sev = &to_kvm_svm(src_kvm)->sev_info; 1613 1614 mutex_unlock(&dst_kvm->lock); 1615 mutex_unlock(&src_kvm->lock); 1616 atomic_set_release(&dst_sev->migration_in_progress, 0); 1617 atomic_set_release(&src_sev->migration_in_progress, 0); 1618 } 1619 1620 /* vCPU mutex subclasses. */ 1621 enum sev_migration_role { 1622 SEV_MIGRATION_SOURCE = 0, 1623 SEV_MIGRATION_TARGET, 1624 SEV_NR_MIGRATION_ROLES, 1625 }; 1626 1627 static int sev_lock_vcpus_for_migration(struct kvm *kvm, 1628 enum sev_migration_role role) 1629 { 1630 struct kvm_vcpu *vcpu; 1631 unsigned long i, j; 1632 1633 kvm_for_each_vcpu(i, vcpu, kvm) { 1634 if (mutex_lock_killable_nested(&vcpu->mutex, role)) 1635 goto out_unlock; 1636 1637 #ifdef CONFIG_PROVE_LOCKING 1638 if (!i) 1639 /* 1640 * Reset the role to one that avoids colliding with 1641 * the role used for the first vcpu mutex. 1642 */ 1643 role = SEV_NR_MIGRATION_ROLES; 1644 else 1645 mutex_release(&vcpu->mutex.dep_map, _THIS_IP_); 1646 #endif 1647 } 1648 1649 return 0; 1650 1651 out_unlock: 1652 1653 kvm_for_each_vcpu(j, vcpu, kvm) { 1654 if (i == j) 1655 break; 1656 1657 #ifdef CONFIG_PROVE_LOCKING 1658 if (j) 1659 mutex_acquire(&vcpu->mutex.dep_map, role, 0, _THIS_IP_); 1660 #endif 1661 1662 mutex_unlock(&vcpu->mutex); 1663 } 1664 return -EINTR; 1665 } 1666 1667 static void sev_unlock_vcpus_for_migration(struct kvm *kvm) 1668 { 1669 struct kvm_vcpu *vcpu; 1670 unsigned long i; 1671 bool first = true; 1672 1673 kvm_for_each_vcpu(i, vcpu, kvm) { 1674 if (first) 1675 first = false; 1676 else 1677 mutex_acquire(&vcpu->mutex.dep_map, 1678 SEV_NR_MIGRATION_ROLES, 0, _THIS_IP_); 1679 1680 mutex_unlock(&vcpu->mutex); 1681 } 1682 } 1683 1684 static void sev_migrate_from(struct kvm *dst_kvm, struct kvm *src_kvm) 1685 { 1686 struct kvm_sev_info *dst = &to_kvm_svm(dst_kvm)->sev_info; 1687 struct kvm_sev_info *src = &to_kvm_svm(src_kvm)->sev_info; 1688 struct kvm_vcpu *dst_vcpu, *src_vcpu; 1689 struct vcpu_svm *dst_svm, *src_svm; 1690 struct kvm_sev_info *mirror; 1691 unsigned long i; 1692 1693 dst->active = true; 1694 dst->asid = src->asid; 1695 dst->handle = src->handle; 1696 dst->pages_locked = src->pages_locked; 1697 dst->enc_context_owner = src->enc_context_owner; 1698 dst->es_active = src->es_active; 1699 1700 src->asid = 0; 1701 src->active = false; 1702 src->handle = 0; 1703 src->pages_locked = 0; 1704 src->enc_context_owner = NULL; 1705 src->es_active = false; 1706 1707 list_cut_before(&dst->regions_list, &src->regions_list, &src->regions_list); 1708 1709 /* 1710 * If this VM has mirrors, "transfer" each mirror's refcount of the 1711 * source to the destination (this KVM). The caller holds a reference 1712 * to the source, so there's no danger of use-after-free. 1713 */ 1714 list_cut_before(&dst->mirror_vms, &src->mirror_vms, &src->mirror_vms); 1715 list_for_each_entry(mirror, &dst->mirror_vms, mirror_entry) { 1716 kvm_get_kvm(dst_kvm); 1717 kvm_put_kvm(src_kvm); 1718 mirror->enc_context_owner = dst_kvm; 1719 } 1720 1721 /* 1722 * If this VM is a mirror, remove the old mirror from the owners list 1723 * and add the new mirror to the list. 1724 */ 1725 if (is_mirroring_enc_context(dst_kvm)) { 1726 struct kvm_sev_info *owner_sev_info = 1727 &to_kvm_svm(dst->enc_context_owner)->sev_info; 1728 1729 list_del(&src->mirror_entry); 1730 list_add_tail(&dst->mirror_entry, &owner_sev_info->mirror_vms); 1731 } 1732 1733 kvm_for_each_vcpu(i, dst_vcpu, dst_kvm) { 1734 dst_svm = to_svm(dst_vcpu); 1735 1736 sev_init_vmcb(dst_svm); 1737 1738 if (!dst->es_active) 1739 continue; 1740 1741 /* 1742 * Note, the source is not required to have the same number of 1743 * vCPUs as the destination when migrating a vanilla SEV VM. 1744 */ 1745 src_vcpu = kvm_get_vcpu(src_kvm, i); 1746 src_svm = to_svm(src_vcpu); 1747 1748 /* 1749 * Transfer VMSA and GHCB state to the destination. Nullify and 1750 * clear source fields as appropriate, the state now belongs to 1751 * the destination. 1752 */ 1753 memcpy(&dst_svm->sev_es, &src_svm->sev_es, sizeof(src_svm->sev_es)); 1754 dst_svm->vmcb->control.ghcb_gpa = src_svm->vmcb->control.ghcb_gpa; 1755 dst_svm->vmcb->control.vmsa_pa = src_svm->vmcb->control.vmsa_pa; 1756 dst_vcpu->arch.guest_state_protected = true; 1757 1758 memset(&src_svm->sev_es, 0, sizeof(src_svm->sev_es)); 1759 src_svm->vmcb->control.ghcb_gpa = INVALID_PAGE; 1760 src_svm->vmcb->control.vmsa_pa = INVALID_PAGE; 1761 src_vcpu->arch.guest_state_protected = false; 1762 } 1763 } 1764 1765 static int sev_check_source_vcpus(struct kvm *dst, struct kvm *src) 1766 { 1767 struct kvm_vcpu *src_vcpu; 1768 unsigned long i; 1769 1770 if (!sev_es_guest(src)) 1771 return 0; 1772 1773 if (atomic_read(&src->online_vcpus) != atomic_read(&dst->online_vcpus)) 1774 return -EINVAL; 1775 1776 kvm_for_each_vcpu(i, src_vcpu, src) { 1777 if (!src_vcpu->arch.guest_state_protected) 1778 return -EINVAL; 1779 } 1780 1781 return 0; 1782 } 1783 1784 int sev_vm_move_enc_context_from(struct kvm *kvm, unsigned int source_fd) 1785 { 1786 struct kvm_sev_info *dst_sev = &to_kvm_svm(kvm)->sev_info; 1787 struct kvm_sev_info *src_sev, *cg_cleanup_sev; 1788 struct fd f = fdget(source_fd); 1789 struct kvm *source_kvm; 1790 bool charged = false; 1791 int ret; 1792 1793 if (!f.file) 1794 return -EBADF; 1795 1796 if (!file_is_kvm(f.file)) { 1797 ret = -EBADF; 1798 goto out_fput; 1799 } 1800 1801 source_kvm = f.file->private_data; 1802 ret = sev_lock_two_vms(kvm, source_kvm); 1803 if (ret) 1804 goto out_fput; 1805 1806 if (sev_guest(kvm) || !sev_guest(source_kvm)) { 1807 ret = -EINVAL; 1808 goto out_unlock; 1809 } 1810 1811 src_sev = &to_kvm_svm(source_kvm)->sev_info; 1812 1813 dst_sev->misc_cg = get_current_misc_cg(); 1814 cg_cleanup_sev = dst_sev; 1815 if (dst_sev->misc_cg != src_sev->misc_cg) { 1816 ret = sev_misc_cg_try_charge(dst_sev); 1817 if (ret) 1818 goto out_dst_cgroup; 1819 charged = true; 1820 } 1821 1822 ret = sev_lock_vcpus_for_migration(kvm, SEV_MIGRATION_SOURCE); 1823 if (ret) 1824 goto out_dst_cgroup; 1825 ret = sev_lock_vcpus_for_migration(source_kvm, SEV_MIGRATION_TARGET); 1826 if (ret) 1827 goto out_dst_vcpu; 1828 1829 ret = sev_check_source_vcpus(kvm, source_kvm); 1830 if (ret) 1831 goto out_source_vcpu; 1832 1833 sev_migrate_from(kvm, source_kvm); 1834 kvm_vm_dead(source_kvm); 1835 cg_cleanup_sev = src_sev; 1836 ret = 0; 1837 1838 out_source_vcpu: 1839 sev_unlock_vcpus_for_migration(source_kvm); 1840 out_dst_vcpu: 1841 sev_unlock_vcpus_for_migration(kvm); 1842 out_dst_cgroup: 1843 /* Operates on the source on success, on the destination on failure. */ 1844 if (charged) 1845 sev_misc_cg_uncharge(cg_cleanup_sev); 1846 put_misc_cg(cg_cleanup_sev->misc_cg); 1847 cg_cleanup_sev->misc_cg = NULL; 1848 out_unlock: 1849 sev_unlock_two_vms(kvm, source_kvm); 1850 out_fput: 1851 fdput(f); 1852 return ret; 1853 } 1854 1855 int sev_mem_enc_ioctl(struct kvm *kvm, void __user *argp) 1856 { 1857 struct kvm_sev_cmd sev_cmd; 1858 int r; 1859 1860 if (!sev_enabled) 1861 return -ENOTTY; 1862 1863 if (!argp) 1864 return 0; 1865 1866 if (copy_from_user(&sev_cmd, argp, sizeof(struct kvm_sev_cmd))) 1867 return -EFAULT; 1868 1869 mutex_lock(&kvm->lock); 1870 1871 /* Only the enc_context_owner handles some memory enc operations. */ 1872 if (is_mirroring_enc_context(kvm) && 1873 !is_cmd_allowed_from_mirror(sev_cmd.id)) { 1874 r = -EINVAL; 1875 goto out; 1876 } 1877 1878 switch (sev_cmd.id) { 1879 case KVM_SEV_ES_INIT: 1880 if (!sev_es_enabled) { 1881 r = -ENOTTY; 1882 goto out; 1883 } 1884 fallthrough; 1885 case KVM_SEV_INIT: 1886 r = sev_guest_init(kvm, &sev_cmd); 1887 break; 1888 case KVM_SEV_LAUNCH_START: 1889 r = sev_launch_start(kvm, &sev_cmd); 1890 break; 1891 case KVM_SEV_LAUNCH_UPDATE_DATA: 1892 r = sev_launch_update_data(kvm, &sev_cmd); 1893 break; 1894 case KVM_SEV_LAUNCH_UPDATE_VMSA: 1895 r = sev_launch_update_vmsa(kvm, &sev_cmd); 1896 break; 1897 case KVM_SEV_LAUNCH_MEASURE: 1898 r = sev_launch_measure(kvm, &sev_cmd); 1899 break; 1900 case KVM_SEV_LAUNCH_FINISH: 1901 r = sev_launch_finish(kvm, &sev_cmd); 1902 break; 1903 case KVM_SEV_GUEST_STATUS: 1904 r = sev_guest_status(kvm, &sev_cmd); 1905 break; 1906 case KVM_SEV_DBG_DECRYPT: 1907 r = sev_dbg_crypt(kvm, &sev_cmd, true); 1908 break; 1909 case KVM_SEV_DBG_ENCRYPT: 1910 r = sev_dbg_crypt(kvm, &sev_cmd, false); 1911 break; 1912 case KVM_SEV_LAUNCH_SECRET: 1913 r = sev_launch_secret(kvm, &sev_cmd); 1914 break; 1915 case KVM_SEV_GET_ATTESTATION_REPORT: 1916 r = sev_get_attestation_report(kvm, &sev_cmd); 1917 break; 1918 case KVM_SEV_SEND_START: 1919 r = sev_send_start(kvm, &sev_cmd); 1920 break; 1921 case KVM_SEV_SEND_UPDATE_DATA: 1922 r = sev_send_update_data(kvm, &sev_cmd); 1923 break; 1924 case KVM_SEV_SEND_FINISH: 1925 r = sev_send_finish(kvm, &sev_cmd); 1926 break; 1927 case KVM_SEV_SEND_CANCEL: 1928 r = sev_send_cancel(kvm, &sev_cmd); 1929 break; 1930 case KVM_SEV_RECEIVE_START: 1931 r = sev_receive_start(kvm, &sev_cmd); 1932 break; 1933 case KVM_SEV_RECEIVE_UPDATE_DATA: 1934 r = sev_receive_update_data(kvm, &sev_cmd); 1935 break; 1936 case KVM_SEV_RECEIVE_FINISH: 1937 r = sev_receive_finish(kvm, &sev_cmd); 1938 break; 1939 default: 1940 r = -EINVAL; 1941 goto out; 1942 } 1943 1944 if (copy_to_user(argp, &sev_cmd, sizeof(struct kvm_sev_cmd))) 1945 r = -EFAULT; 1946 1947 out: 1948 mutex_unlock(&kvm->lock); 1949 return r; 1950 } 1951 1952 int sev_mem_enc_register_region(struct kvm *kvm, 1953 struct kvm_enc_region *range) 1954 { 1955 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 1956 struct enc_region *region; 1957 int ret = 0; 1958 1959 if (!sev_guest(kvm)) 1960 return -ENOTTY; 1961 1962 /* If kvm is mirroring encryption context it isn't responsible for it */ 1963 if (is_mirroring_enc_context(kvm)) 1964 return -EINVAL; 1965 1966 if (range->addr > ULONG_MAX || range->size > ULONG_MAX) 1967 return -EINVAL; 1968 1969 region = kzalloc(sizeof(*region), GFP_KERNEL_ACCOUNT); 1970 if (!region) 1971 return -ENOMEM; 1972 1973 mutex_lock(&kvm->lock); 1974 region->pages = sev_pin_memory(kvm, range->addr, range->size, ®ion->npages, 1); 1975 if (IS_ERR(region->pages)) { 1976 ret = PTR_ERR(region->pages); 1977 mutex_unlock(&kvm->lock); 1978 goto e_free; 1979 } 1980 1981 region->uaddr = range->addr; 1982 region->size = range->size; 1983 1984 list_add_tail(®ion->list, &sev->regions_list); 1985 mutex_unlock(&kvm->lock); 1986 1987 /* 1988 * The guest may change the memory encryption attribute from C=0 -> C=1 1989 * or vice versa for this memory range. Lets make sure caches are 1990 * flushed to ensure that guest data gets written into memory with 1991 * correct C-bit. 1992 */ 1993 sev_clflush_pages(region->pages, region->npages); 1994 1995 return ret; 1996 1997 e_free: 1998 kfree(region); 1999 return ret; 2000 } 2001 2002 static struct enc_region * 2003 find_enc_region(struct kvm *kvm, struct kvm_enc_region *range) 2004 { 2005 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 2006 struct list_head *head = &sev->regions_list; 2007 struct enc_region *i; 2008 2009 list_for_each_entry(i, head, list) { 2010 if (i->uaddr == range->addr && 2011 i->size == range->size) 2012 return i; 2013 } 2014 2015 return NULL; 2016 } 2017 2018 static void __unregister_enc_region_locked(struct kvm *kvm, 2019 struct enc_region *region) 2020 { 2021 sev_unpin_memory(kvm, region->pages, region->npages); 2022 list_del(®ion->list); 2023 kfree(region); 2024 } 2025 2026 int sev_mem_enc_unregister_region(struct kvm *kvm, 2027 struct kvm_enc_region *range) 2028 { 2029 struct enc_region *region; 2030 int ret; 2031 2032 /* If kvm is mirroring encryption context it isn't responsible for it */ 2033 if (is_mirroring_enc_context(kvm)) 2034 return -EINVAL; 2035 2036 mutex_lock(&kvm->lock); 2037 2038 if (!sev_guest(kvm)) { 2039 ret = -ENOTTY; 2040 goto failed; 2041 } 2042 2043 region = find_enc_region(kvm, range); 2044 if (!region) { 2045 ret = -EINVAL; 2046 goto failed; 2047 } 2048 2049 /* 2050 * Ensure that all guest tagged cache entries are flushed before 2051 * releasing the pages back to the system for use. CLFLUSH will 2052 * not do this, so issue a WBINVD. 2053 */ 2054 wbinvd_on_all_cpus(); 2055 2056 __unregister_enc_region_locked(kvm, region); 2057 2058 mutex_unlock(&kvm->lock); 2059 return 0; 2060 2061 failed: 2062 mutex_unlock(&kvm->lock); 2063 return ret; 2064 } 2065 2066 int sev_vm_copy_enc_context_from(struct kvm *kvm, unsigned int source_fd) 2067 { 2068 struct fd f = fdget(source_fd); 2069 struct kvm *source_kvm; 2070 struct kvm_sev_info *source_sev, *mirror_sev; 2071 int ret; 2072 2073 if (!f.file) 2074 return -EBADF; 2075 2076 if (!file_is_kvm(f.file)) { 2077 ret = -EBADF; 2078 goto e_source_fput; 2079 } 2080 2081 source_kvm = f.file->private_data; 2082 ret = sev_lock_two_vms(kvm, source_kvm); 2083 if (ret) 2084 goto e_source_fput; 2085 2086 /* 2087 * Mirrors of mirrors should work, but let's not get silly. Also 2088 * disallow out-of-band SEV/SEV-ES init if the target is already an 2089 * SEV guest, or if vCPUs have been created. KVM relies on vCPUs being 2090 * created after SEV/SEV-ES initialization, e.g. to init intercepts. 2091 */ 2092 if (sev_guest(kvm) || !sev_guest(source_kvm) || 2093 is_mirroring_enc_context(source_kvm) || kvm->created_vcpus) { 2094 ret = -EINVAL; 2095 goto e_unlock; 2096 } 2097 2098 /* 2099 * The mirror kvm holds an enc_context_owner ref so its asid can't 2100 * disappear until we're done with it 2101 */ 2102 source_sev = &to_kvm_svm(source_kvm)->sev_info; 2103 kvm_get_kvm(source_kvm); 2104 mirror_sev = &to_kvm_svm(kvm)->sev_info; 2105 list_add_tail(&mirror_sev->mirror_entry, &source_sev->mirror_vms); 2106 2107 /* Set enc_context_owner and copy its encryption context over */ 2108 mirror_sev->enc_context_owner = source_kvm; 2109 mirror_sev->active = true; 2110 mirror_sev->asid = source_sev->asid; 2111 mirror_sev->fd = source_sev->fd; 2112 mirror_sev->es_active = source_sev->es_active; 2113 mirror_sev->handle = source_sev->handle; 2114 INIT_LIST_HEAD(&mirror_sev->regions_list); 2115 INIT_LIST_HEAD(&mirror_sev->mirror_vms); 2116 ret = 0; 2117 2118 /* 2119 * Do not copy ap_jump_table. Since the mirror does not share the same 2120 * KVM contexts as the original, and they may have different 2121 * memory-views. 2122 */ 2123 2124 e_unlock: 2125 sev_unlock_two_vms(kvm, source_kvm); 2126 e_source_fput: 2127 fdput(f); 2128 return ret; 2129 } 2130 2131 void sev_vm_destroy(struct kvm *kvm) 2132 { 2133 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 2134 struct list_head *head = &sev->regions_list; 2135 struct list_head *pos, *q; 2136 2137 if (!sev_guest(kvm)) 2138 return; 2139 2140 WARN_ON(!list_empty(&sev->mirror_vms)); 2141 2142 /* If this is a mirror_kvm release the enc_context_owner and skip sev cleanup */ 2143 if (is_mirroring_enc_context(kvm)) { 2144 struct kvm *owner_kvm = sev->enc_context_owner; 2145 2146 mutex_lock(&owner_kvm->lock); 2147 list_del(&sev->mirror_entry); 2148 mutex_unlock(&owner_kvm->lock); 2149 kvm_put_kvm(owner_kvm); 2150 return; 2151 } 2152 2153 /* 2154 * Ensure that all guest tagged cache entries are flushed before 2155 * releasing the pages back to the system for use. CLFLUSH will 2156 * not do this, so issue a WBINVD. 2157 */ 2158 wbinvd_on_all_cpus(); 2159 2160 /* 2161 * if userspace was terminated before unregistering the memory regions 2162 * then lets unpin all the registered memory. 2163 */ 2164 if (!list_empty(head)) { 2165 list_for_each_safe(pos, q, head) { 2166 __unregister_enc_region_locked(kvm, 2167 list_entry(pos, struct enc_region, list)); 2168 cond_resched(); 2169 } 2170 } 2171 2172 sev_unbind_asid(kvm, sev->handle); 2173 sev_asid_free(sev); 2174 } 2175 2176 void __init sev_set_cpu_caps(void) 2177 { 2178 if (!sev_enabled) 2179 kvm_cpu_cap_clear(X86_FEATURE_SEV); 2180 if (!sev_es_enabled) 2181 kvm_cpu_cap_clear(X86_FEATURE_SEV_ES); 2182 } 2183 2184 void __init sev_hardware_setup(void) 2185 { 2186 #ifdef CONFIG_KVM_AMD_SEV 2187 unsigned int eax, ebx, ecx, edx, sev_asid_count, sev_es_asid_count; 2188 bool sev_es_supported = false; 2189 bool sev_supported = false; 2190 2191 if (!sev_enabled || !npt_enabled || !nrips) 2192 goto out; 2193 2194 /* 2195 * SEV must obviously be supported in hardware. Sanity check that the 2196 * CPU supports decode assists, which is mandatory for SEV guests to 2197 * support instruction emulation. Ditto for flushing by ASID, as SEV 2198 * guests are bound to a single ASID, i.e. KVM can't rotate to a new 2199 * ASID to effect a TLB flush. 2200 */ 2201 if (!boot_cpu_has(X86_FEATURE_SEV) || 2202 WARN_ON_ONCE(!boot_cpu_has(X86_FEATURE_DECODEASSISTS)) || 2203 WARN_ON_ONCE(!boot_cpu_has(X86_FEATURE_FLUSHBYASID))) 2204 goto out; 2205 2206 /* Retrieve SEV CPUID information */ 2207 cpuid(0x8000001f, &eax, &ebx, &ecx, &edx); 2208 2209 /* Set encryption bit location for SEV-ES guests */ 2210 sev_enc_bit = ebx & 0x3f; 2211 2212 /* Maximum number of encrypted guests supported simultaneously */ 2213 max_sev_asid = ecx; 2214 if (!max_sev_asid) 2215 goto out; 2216 2217 /* Minimum ASID value that should be used for SEV guest */ 2218 min_sev_asid = edx; 2219 sev_me_mask = 1UL << (ebx & 0x3f); 2220 2221 /* 2222 * Initialize SEV ASID bitmaps. Allocate space for ASID 0 in the bitmap, 2223 * even though it's never used, so that the bitmap is indexed by the 2224 * actual ASID. 2225 */ 2226 nr_asids = max_sev_asid + 1; 2227 sev_asid_bitmap = bitmap_zalloc(nr_asids, GFP_KERNEL); 2228 if (!sev_asid_bitmap) 2229 goto out; 2230 2231 sev_reclaim_asid_bitmap = bitmap_zalloc(nr_asids, GFP_KERNEL); 2232 if (!sev_reclaim_asid_bitmap) { 2233 bitmap_free(sev_asid_bitmap); 2234 sev_asid_bitmap = NULL; 2235 goto out; 2236 } 2237 2238 sev_asid_count = max_sev_asid - min_sev_asid + 1; 2239 WARN_ON_ONCE(misc_cg_set_capacity(MISC_CG_RES_SEV, sev_asid_count)); 2240 sev_supported = true; 2241 2242 /* SEV-ES support requested? */ 2243 if (!sev_es_enabled) 2244 goto out; 2245 2246 /* 2247 * SEV-ES requires MMIO caching as KVM doesn't have access to the guest 2248 * instruction stream, i.e. can't emulate in response to a #NPF and 2249 * instead relies on #NPF(RSVD) being reflected into the guest as #VC 2250 * (the guest can then do a #VMGEXIT to request MMIO emulation). 2251 */ 2252 if (!enable_mmio_caching) 2253 goto out; 2254 2255 /* Does the CPU support SEV-ES? */ 2256 if (!boot_cpu_has(X86_FEATURE_SEV_ES)) 2257 goto out; 2258 2259 /* Has the system been allocated ASIDs for SEV-ES? */ 2260 if (min_sev_asid == 1) 2261 goto out; 2262 2263 sev_es_asid_count = min_sev_asid - 1; 2264 WARN_ON_ONCE(misc_cg_set_capacity(MISC_CG_RES_SEV_ES, sev_es_asid_count)); 2265 sev_es_supported = true; 2266 2267 out: 2268 if (boot_cpu_has(X86_FEATURE_SEV)) 2269 pr_info("SEV %s (ASIDs %u - %u)\n", 2270 sev_supported ? "enabled" : "disabled", 2271 min_sev_asid, max_sev_asid); 2272 if (boot_cpu_has(X86_FEATURE_SEV_ES)) 2273 pr_info("SEV-ES %s (ASIDs %u - %u)\n", 2274 sev_es_supported ? "enabled" : "disabled", 2275 min_sev_asid > 1 ? 1 : 0, min_sev_asid - 1); 2276 2277 sev_enabled = sev_supported; 2278 sev_es_enabled = sev_es_supported; 2279 if (!sev_es_enabled || !cpu_feature_enabled(X86_FEATURE_DEBUG_SWAP) || 2280 !cpu_feature_enabled(X86_FEATURE_NO_NESTED_DATA_BP)) 2281 sev_es_debug_swap_enabled = false; 2282 #endif 2283 } 2284 2285 void sev_hardware_unsetup(void) 2286 { 2287 if (!sev_enabled) 2288 return; 2289 2290 /* No need to take sev_bitmap_lock, all VMs have been destroyed. */ 2291 sev_flush_asids(1, max_sev_asid); 2292 2293 bitmap_free(sev_asid_bitmap); 2294 bitmap_free(sev_reclaim_asid_bitmap); 2295 2296 misc_cg_set_capacity(MISC_CG_RES_SEV, 0); 2297 misc_cg_set_capacity(MISC_CG_RES_SEV_ES, 0); 2298 } 2299 2300 int sev_cpu_init(struct svm_cpu_data *sd) 2301 { 2302 if (!sev_enabled) 2303 return 0; 2304 2305 sd->sev_vmcbs = kcalloc(nr_asids, sizeof(void *), GFP_KERNEL); 2306 if (!sd->sev_vmcbs) 2307 return -ENOMEM; 2308 2309 return 0; 2310 } 2311 2312 /* 2313 * Pages used by hardware to hold guest encrypted state must be flushed before 2314 * returning them to the system. 2315 */ 2316 static void sev_flush_encrypted_page(struct kvm_vcpu *vcpu, void *va) 2317 { 2318 int asid = to_kvm_svm(vcpu->kvm)->sev_info.asid; 2319 2320 /* 2321 * Note! The address must be a kernel address, as regular page walk 2322 * checks are performed by VM_PAGE_FLUSH, i.e. operating on a user 2323 * address is non-deterministic and unsafe. This function deliberately 2324 * takes a pointer to deter passing in a user address. 2325 */ 2326 unsigned long addr = (unsigned long)va; 2327 2328 /* 2329 * If CPU enforced cache coherency for encrypted mappings of the 2330 * same physical page is supported, use CLFLUSHOPT instead. NOTE: cache 2331 * flush is still needed in order to work properly with DMA devices. 2332 */ 2333 if (boot_cpu_has(X86_FEATURE_SME_COHERENT)) { 2334 clflush_cache_range(va, PAGE_SIZE); 2335 return; 2336 } 2337 2338 /* 2339 * VM Page Flush takes a host virtual address and a guest ASID. Fall 2340 * back to WBINVD if this faults so as not to make any problems worse 2341 * by leaving stale encrypted data in the cache. 2342 */ 2343 if (WARN_ON_ONCE(wrmsrl_safe(MSR_AMD64_VM_PAGE_FLUSH, addr | asid))) 2344 goto do_wbinvd; 2345 2346 return; 2347 2348 do_wbinvd: 2349 wbinvd_on_all_cpus(); 2350 } 2351 2352 void sev_guest_memory_reclaimed(struct kvm *kvm) 2353 { 2354 if (!sev_guest(kvm)) 2355 return; 2356 2357 wbinvd_on_all_cpus(); 2358 } 2359 2360 void sev_free_vcpu(struct kvm_vcpu *vcpu) 2361 { 2362 struct vcpu_svm *svm; 2363 2364 if (!sev_es_guest(vcpu->kvm)) 2365 return; 2366 2367 svm = to_svm(vcpu); 2368 2369 if (vcpu->arch.guest_state_protected) 2370 sev_flush_encrypted_page(vcpu, svm->sev_es.vmsa); 2371 2372 __free_page(virt_to_page(svm->sev_es.vmsa)); 2373 2374 if (svm->sev_es.ghcb_sa_free) 2375 kvfree(svm->sev_es.ghcb_sa); 2376 } 2377 2378 static void dump_ghcb(struct vcpu_svm *svm) 2379 { 2380 struct ghcb *ghcb = svm->sev_es.ghcb; 2381 unsigned int nbits; 2382 2383 /* Re-use the dump_invalid_vmcb module parameter */ 2384 if (!dump_invalid_vmcb) { 2385 pr_warn_ratelimited("set kvm_amd.dump_invalid_vmcb=1 to dump internal KVM state.\n"); 2386 return; 2387 } 2388 2389 nbits = sizeof(ghcb->save.valid_bitmap) * 8; 2390 2391 pr_err("GHCB (GPA=%016llx):\n", svm->vmcb->control.ghcb_gpa); 2392 pr_err("%-20s%016llx is_valid: %u\n", "sw_exit_code", 2393 ghcb->save.sw_exit_code, ghcb_sw_exit_code_is_valid(ghcb)); 2394 pr_err("%-20s%016llx is_valid: %u\n", "sw_exit_info_1", 2395 ghcb->save.sw_exit_info_1, ghcb_sw_exit_info_1_is_valid(ghcb)); 2396 pr_err("%-20s%016llx is_valid: %u\n", "sw_exit_info_2", 2397 ghcb->save.sw_exit_info_2, ghcb_sw_exit_info_2_is_valid(ghcb)); 2398 pr_err("%-20s%016llx is_valid: %u\n", "sw_scratch", 2399 ghcb->save.sw_scratch, ghcb_sw_scratch_is_valid(ghcb)); 2400 pr_err("%-20s%*pb\n", "valid_bitmap", nbits, ghcb->save.valid_bitmap); 2401 } 2402 2403 static void sev_es_sync_to_ghcb(struct vcpu_svm *svm) 2404 { 2405 struct kvm_vcpu *vcpu = &svm->vcpu; 2406 struct ghcb *ghcb = svm->sev_es.ghcb; 2407 2408 /* 2409 * The GHCB protocol so far allows for the following data 2410 * to be returned: 2411 * GPRs RAX, RBX, RCX, RDX 2412 * 2413 * Copy their values, even if they may not have been written during the 2414 * VM-Exit. It's the guest's responsibility to not consume random data. 2415 */ 2416 ghcb_set_rax(ghcb, vcpu->arch.regs[VCPU_REGS_RAX]); 2417 ghcb_set_rbx(ghcb, vcpu->arch.regs[VCPU_REGS_RBX]); 2418 ghcb_set_rcx(ghcb, vcpu->arch.regs[VCPU_REGS_RCX]); 2419 ghcb_set_rdx(ghcb, vcpu->arch.regs[VCPU_REGS_RDX]); 2420 } 2421 2422 static void sev_es_sync_from_ghcb(struct vcpu_svm *svm) 2423 { 2424 struct vmcb_control_area *control = &svm->vmcb->control; 2425 struct kvm_vcpu *vcpu = &svm->vcpu; 2426 struct ghcb *ghcb = svm->sev_es.ghcb; 2427 u64 exit_code; 2428 2429 /* 2430 * The GHCB protocol so far allows for the following data 2431 * to be supplied: 2432 * GPRs RAX, RBX, RCX, RDX 2433 * XCR0 2434 * CPL 2435 * 2436 * VMMCALL allows the guest to provide extra registers. KVM also 2437 * expects RSI for hypercalls, so include that, too. 2438 * 2439 * Copy their values to the appropriate location if supplied. 2440 */ 2441 memset(vcpu->arch.regs, 0, sizeof(vcpu->arch.regs)); 2442 2443 BUILD_BUG_ON(sizeof(svm->sev_es.valid_bitmap) != sizeof(ghcb->save.valid_bitmap)); 2444 memcpy(&svm->sev_es.valid_bitmap, &ghcb->save.valid_bitmap, sizeof(ghcb->save.valid_bitmap)); 2445 2446 vcpu->arch.regs[VCPU_REGS_RAX] = kvm_ghcb_get_rax_if_valid(svm, ghcb); 2447 vcpu->arch.regs[VCPU_REGS_RBX] = kvm_ghcb_get_rbx_if_valid(svm, ghcb); 2448 vcpu->arch.regs[VCPU_REGS_RCX] = kvm_ghcb_get_rcx_if_valid(svm, ghcb); 2449 vcpu->arch.regs[VCPU_REGS_RDX] = kvm_ghcb_get_rdx_if_valid(svm, ghcb); 2450 vcpu->arch.regs[VCPU_REGS_RSI] = kvm_ghcb_get_rsi_if_valid(svm, ghcb); 2451 2452 svm->vmcb->save.cpl = kvm_ghcb_get_cpl_if_valid(svm, ghcb); 2453 2454 if (kvm_ghcb_xcr0_is_valid(svm)) { 2455 vcpu->arch.xcr0 = ghcb_get_xcr0(ghcb); 2456 kvm_update_cpuid_runtime(vcpu); 2457 } 2458 2459 /* Copy the GHCB exit information into the VMCB fields */ 2460 exit_code = ghcb_get_sw_exit_code(ghcb); 2461 control->exit_code = lower_32_bits(exit_code); 2462 control->exit_code_hi = upper_32_bits(exit_code); 2463 control->exit_info_1 = ghcb_get_sw_exit_info_1(ghcb); 2464 control->exit_info_2 = ghcb_get_sw_exit_info_2(ghcb); 2465 svm->sev_es.sw_scratch = kvm_ghcb_get_sw_scratch_if_valid(svm, ghcb); 2466 2467 /* Clear the valid entries fields */ 2468 memset(ghcb->save.valid_bitmap, 0, sizeof(ghcb->save.valid_bitmap)); 2469 } 2470 2471 static u64 kvm_ghcb_get_sw_exit_code(struct vmcb_control_area *control) 2472 { 2473 return (((u64)control->exit_code_hi) << 32) | control->exit_code; 2474 } 2475 2476 static int sev_es_validate_vmgexit(struct vcpu_svm *svm) 2477 { 2478 struct vmcb_control_area *control = &svm->vmcb->control; 2479 struct kvm_vcpu *vcpu = &svm->vcpu; 2480 u64 exit_code; 2481 u64 reason; 2482 2483 /* 2484 * Retrieve the exit code now even though it may not be marked valid 2485 * as it could help with debugging. 2486 */ 2487 exit_code = kvm_ghcb_get_sw_exit_code(control); 2488 2489 /* Only GHCB Usage code 0 is supported */ 2490 if (svm->sev_es.ghcb->ghcb_usage) { 2491 reason = GHCB_ERR_INVALID_USAGE; 2492 goto vmgexit_err; 2493 } 2494 2495 reason = GHCB_ERR_MISSING_INPUT; 2496 2497 if (!kvm_ghcb_sw_exit_code_is_valid(svm) || 2498 !kvm_ghcb_sw_exit_info_1_is_valid(svm) || 2499 !kvm_ghcb_sw_exit_info_2_is_valid(svm)) 2500 goto vmgexit_err; 2501 2502 switch (exit_code) { 2503 case SVM_EXIT_READ_DR7: 2504 break; 2505 case SVM_EXIT_WRITE_DR7: 2506 if (!kvm_ghcb_rax_is_valid(svm)) 2507 goto vmgexit_err; 2508 break; 2509 case SVM_EXIT_RDTSC: 2510 break; 2511 case SVM_EXIT_RDPMC: 2512 if (!kvm_ghcb_rcx_is_valid(svm)) 2513 goto vmgexit_err; 2514 break; 2515 case SVM_EXIT_CPUID: 2516 if (!kvm_ghcb_rax_is_valid(svm) || 2517 !kvm_ghcb_rcx_is_valid(svm)) 2518 goto vmgexit_err; 2519 if (vcpu->arch.regs[VCPU_REGS_RAX] == 0xd) 2520 if (!kvm_ghcb_xcr0_is_valid(svm)) 2521 goto vmgexit_err; 2522 break; 2523 case SVM_EXIT_INVD: 2524 break; 2525 case SVM_EXIT_IOIO: 2526 if (control->exit_info_1 & SVM_IOIO_STR_MASK) { 2527 if (!kvm_ghcb_sw_scratch_is_valid(svm)) 2528 goto vmgexit_err; 2529 } else { 2530 if (!(control->exit_info_1 & SVM_IOIO_TYPE_MASK)) 2531 if (!kvm_ghcb_rax_is_valid(svm)) 2532 goto vmgexit_err; 2533 } 2534 break; 2535 case SVM_EXIT_MSR: 2536 if (!kvm_ghcb_rcx_is_valid(svm)) 2537 goto vmgexit_err; 2538 if (control->exit_info_1) { 2539 if (!kvm_ghcb_rax_is_valid(svm) || 2540 !kvm_ghcb_rdx_is_valid(svm)) 2541 goto vmgexit_err; 2542 } 2543 break; 2544 case SVM_EXIT_VMMCALL: 2545 if (!kvm_ghcb_rax_is_valid(svm) || 2546 !kvm_ghcb_cpl_is_valid(svm)) 2547 goto vmgexit_err; 2548 break; 2549 case SVM_EXIT_RDTSCP: 2550 break; 2551 case SVM_EXIT_WBINVD: 2552 break; 2553 case SVM_EXIT_MONITOR: 2554 if (!kvm_ghcb_rax_is_valid(svm) || 2555 !kvm_ghcb_rcx_is_valid(svm) || 2556 !kvm_ghcb_rdx_is_valid(svm)) 2557 goto vmgexit_err; 2558 break; 2559 case SVM_EXIT_MWAIT: 2560 if (!kvm_ghcb_rax_is_valid(svm) || 2561 !kvm_ghcb_rcx_is_valid(svm)) 2562 goto vmgexit_err; 2563 break; 2564 case SVM_VMGEXIT_MMIO_READ: 2565 case SVM_VMGEXIT_MMIO_WRITE: 2566 if (!kvm_ghcb_sw_scratch_is_valid(svm)) 2567 goto vmgexit_err; 2568 break; 2569 case SVM_VMGEXIT_NMI_COMPLETE: 2570 case SVM_VMGEXIT_AP_HLT_LOOP: 2571 case SVM_VMGEXIT_AP_JUMP_TABLE: 2572 case SVM_VMGEXIT_UNSUPPORTED_EVENT: 2573 break; 2574 default: 2575 reason = GHCB_ERR_INVALID_EVENT; 2576 goto vmgexit_err; 2577 } 2578 2579 return 0; 2580 2581 vmgexit_err: 2582 if (reason == GHCB_ERR_INVALID_USAGE) { 2583 vcpu_unimpl(vcpu, "vmgexit: ghcb usage %#x is not valid\n", 2584 svm->sev_es.ghcb->ghcb_usage); 2585 } else if (reason == GHCB_ERR_INVALID_EVENT) { 2586 vcpu_unimpl(vcpu, "vmgexit: exit code %#llx is not valid\n", 2587 exit_code); 2588 } else { 2589 vcpu_unimpl(vcpu, "vmgexit: exit code %#llx input is not valid\n", 2590 exit_code); 2591 dump_ghcb(svm); 2592 } 2593 2594 ghcb_set_sw_exit_info_1(svm->sev_es.ghcb, 2); 2595 ghcb_set_sw_exit_info_2(svm->sev_es.ghcb, reason); 2596 2597 /* Resume the guest to "return" the error code. */ 2598 return 1; 2599 } 2600 2601 void sev_es_unmap_ghcb(struct vcpu_svm *svm) 2602 { 2603 if (!svm->sev_es.ghcb) 2604 return; 2605 2606 if (svm->sev_es.ghcb_sa_free) { 2607 /* 2608 * The scratch area lives outside the GHCB, so there is a 2609 * buffer that, depending on the operation performed, may 2610 * need to be synced, then freed. 2611 */ 2612 if (svm->sev_es.ghcb_sa_sync) { 2613 kvm_write_guest(svm->vcpu.kvm, 2614 svm->sev_es.sw_scratch, 2615 svm->sev_es.ghcb_sa, 2616 svm->sev_es.ghcb_sa_len); 2617 svm->sev_es.ghcb_sa_sync = false; 2618 } 2619 2620 kvfree(svm->sev_es.ghcb_sa); 2621 svm->sev_es.ghcb_sa = NULL; 2622 svm->sev_es.ghcb_sa_free = false; 2623 } 2624 2625 trace_kvm_vmgexit_exit(svm->vcpu.vcpu_id, svm->sev_es.ghcb); 2626 2627 sev_es_sync_to_ghcb(svm); 2628 2629 kvm_vcpu_unmap(&svm->vcpu, &svm->sev_es.ghcb_map, true); 2630 svm->sev_es.ghcb = NULL; 2631 } 2632 2633 void pre_sev_run(struct vcpu_svm *svm, int cpu) 2634 { 2635 struct svm_cpu_data *sd = per_cpu_ptr(&svm_data, cpu); 2636 int asid = sev_get_asid(svm->vcpu.kvm); 2637 2638 /* Assign the asid allocated with this SEV guest */ 2639 svm->asid = asid; 2640 2641 /* 2642 * Flush guest TLB: 2643 * 2644 * 1) when different VMCB for the same ASID is to be run on the same host CPU. 2645 * 2) or this VMCB was executed on different host CPU in previous VMRUNs. 2646 */ 2647 if (sd->sev_vmcbs[asid] == svm->vmcb && 2648 svm->vcpu.arch.last_vmentry_cpu == cpu) 2649 return; 2650 2651 sd->sev_vmcbs[asid] = svm->vmcb; 2652 svm->vmcb->control.tlb_ctl = TLB_CONTROL_FLUSH_ASID; 2653 vmcb_mark_dirty(svm->vmcb, VMCB_ASID); 2654 } 2655 2656 #define GHCB_SCRATCH_AREA_LIMIT (16ULL * PAGE_SIZE) 2657 static int setup_vmgexit_scratch(struct vcpu_svm *svm, bool sync, u64 len) 2658 { 2659 struct vmcb_control_area *control = &svm->vmcb->control; 2660 u64 ghcb_scratch_beg, ghcb_scratch_end; 2661 u64 scratch_gpa_beg, scratch_gpa_end; 2662 void *scratch_va; 2663 2664 scratch_gpa_beg = svm->sev_es.sw_scratch; 2665 if (!scratch_gpa_beg) { 2666 pr_err("vmgexit: scratch gpa not provided\n"); 2667 goto e_scratch; 2668 } 2669 2670 scratch_gpa_end = scratch_gpa_beg + len; 2671 if (scratch_gpa_end < scratch_gpa_beg) { 2672 pr_err("vmgexit: scratch length (%#llx) not valid for scratch address (%#llx)\n", 2673 len, scratch_gpa_beg); 2674 goto e_scratch; 2675 } 2676 2677 if ((scratch_gpa_beg & PAGE_MASK) == control->ghcb_gpa) { 2678 /* Scratch area begins within GHCB */ 2679 ghcb_scratch_beg = control->ghcb_gpa + 2680 offsetof(struct ghcb, shared_buffer); 2681 ghcb_scratch_end = control->ghcb_gpa + 2682 offsetof(struct ghcb, reserved_0xff0); 2683 2684 /* 2685 * If the scratch area begins within the GHCB, it must be 2686 * completely contained in the GHCB shared buffer area. 2687 */ 2688 if (scratch_gpa_beg < ghcb_scratch_beg || 2689 scratch_gpa_end > ghcb_scratch_end) { 2690 pr_err("vmgexit: scratch area is outside of GHCB shared buffer area (%#llx - %#llx)\n", 2691 scratch_gpa_beg, scratch_gpa_end); 2692 goto e_scratch; 2693 } 2694 2695 scratch_va = (void *)svm->sev_es.ghcb; 2696 scratch_va += (scratch_gpa_beg - control->ghcb_gpa); 2697 } else { 2698 /* 2699 * The guest memory must be read into a kernel buffer, so 2700 * limit the size 2701 */ 2702 if (len > GHCB_SCRATCH_AREA_LIMIT) { 2703 pr_err("vmgexit: scratch area exceeds KVM limits (%#llx requested, %#llx limit)\n", 2704 len, GHCB_SCRATCH_AREA_LIMIT); 2705 goto e_scratch; 2706 } 2707 scratch_va = kvzalloc(len, GFP_KERNEL_ACCOUNT); 2708 if (!scratch_va) 2709 return -ENOMEM; 2710 2711 if (kvm_read_guest(svm->vcpu.kvm, scratch_gpa_beg, scratch_va, len)) { 2712 /* Unable to copy scratch area from guest */ 2713 pr_err("vmgexit: kvm_read_guest for scratch area failed\n"); 2714 2715 kvfree(scratch_va); 2716 return -EFAULT; 2717 } 2718 2719 /* 2720 * The scratch area is outside the GHCB. The operation will 2721 * dictate whether the buffer needs to be synced before running 2722 * the vCPU next time (i.e. a read was requested so the data 2723 * must be written back to the guest memory). 2724 */ 2725 svm->sev_es.ghcb_sa_sync = sync; 2726 svm->sev_es.ghcb_sa_free = true; 2727 } 2728 2729 svm->sev_es.ghcb_sa = scratch_va; 2730 svm->sev_es.ghcb_sa_len = len; 2731 2732 return 0; 2733 2734 e_scratch: 2735 ghcb_set_sw_exit_info_1(svm->sev_es.ghcb, 2); 2736 ghcb_set_sw_exit_info_2(svm->sev_es.ghcb, GHCB_ERR_INVALID_SCRATCH_AREA); 2737 2738 return 1; 2739 } 2740 2741 static void set_ghcb_msr_bits(struct vcpu_svm *svm, u64 value, u64 mask, 2742 unsigned int pos) 2743 { 2744 svm->vmcb->control.ghcb_gpa &= ~(mask << pos); 2745 svm->vmcb->control.ghcb_gpa |= (value & mask) << pos; 2746 } 2747 2748 static u64 get_ghcb_msr_bits(struct vcpu_svm *svm, u64 mask, unsigned int pos) 2749 { 2750 return (svm->vmcb->control.ghcb_gpa >> pos) & mask; 2751 } 2752 2753 static void set_ghcb_msr(struct vcpu_svm *svm, u64 value) 2754 { 2755 svm->vmcb->control.ghcb_gpa = value; 2756 } 2757 2758 static int sev_handle_vmgexit_msr_protocol(struct vcpu_svm *svm) 2759 { 2760 struct vmcb_control_area *control = &svm->vmcb->control; 2761 struct kvm_vcpu *vcpu = &svm->vcpu; 2762 u64 ghcb_info; 2763 int ret = 1; 2764 2765 ghcb_info = control->ghcb_gpa & GHCB_MSR_INFO_MASK; 2766 2767 trace_kvm_vmgexit_msr_protocol_enter(svm->vcpu.vcpu_id, 2768 control->ghcb_gpa); 2769 2770 switch (ghcb_info) { 2771 case GHCB_MSR_SEV_INFO_REQ: 2772 set_ghcb_msr(svm, GHCB_MSR_SEV_INFO(GHCB_VERSION_MAX, 2773 GHCB_VERSION_MIN, 2774 sev_enc_bit)); 2775 break; 2776 case GHCB_MSR_CPUID_REQ: { 2777 u64 cpuid_fn, cpuid_reg, cpuid_value; 2778 2779 cpuid_fn = get_ghcb_msr_bits(svm, 2780 GHCB_MSR_CPUID_FUNC_MASK, 2781 GHCB_MSR_CPUID_FUNC_POS); 2782 2783 /* Initialize the registers needed by the CPUID intercept */ 2784 vcpu->arch.regs[VCPU_REGS_RAX] = cpuid_fn; 2785 vcpu->arch.regs[VCPU_REGS_RCX] = 0; 2786 2787 ret = svm_invoke_exit_handler(vcpu, SVM_EXIT_CPUID); 2788 if (!ret) { 2789 /* Error, keep GHCB MSR value as-is */ 2790 break; 2791 } 2792 2793 cpuid_reg = get_ghcb_msr_bits(svm, 2794 GHCB_MSR_CPUID_REG_MASK, 2795 GHCB_MSR_CPUID_REG_POS); 2796 if (cpuid_reg == 0) 2797 cpuid_value = vcpu->arch.regs[VCPU_REGS_RAX]; 2798 else if (cpuid_reg == 1) 2799 cpuid_value = vcpu->arch.regs[VCPU_REGS_RBX]; 2800 else if (cpuid_reg == 2) 2801 cpuid_value = vcpu->arch.regs[VCPU_REGS_RCX]; 2802 else 2803 cpuid_value = vcpu->arch.regs[VCPU_REGS_RDX]; 2804 2805 set_ghcb_msr_bits(svm, cpuid_value, 2806 GHCB_MSR_CPUID_VALUE_MASK, 2807 GHCB_MSR_CPUID_VALUE_POS); 2808 2809 set_ghcb_msr_bits(svm, GHCB_MSR_CPUID_RESP, 2810 GHCB_MSR_INFO_MASK, 2811 GHCB_MSR_INFO_POS); 2812 break; 2813 } 2814 case GHCB_MSR_TERM_REQ: { 2815 u64 reason_set, reason_code; 2816 2817 reason_set = get_ghcb_msr_bits(svm, 2818 GHCB_MSR_TERM_REASON_SET_MASK, 2819 GHCB_MSR_TERM_REASON_SET_POS); 2820 reason_code = get_ghcb_msr_bits(svm, 2821 GHCB_MSR_TERM_REASON_MASK, 2822 GHCB_MSR_TERM_REASON_POS); 2823 pr_info("SEV-ES guest requested termination: %#llx:%#llx\n", 2824 reason_set, reason_code); 2825 2826 vcpu->run->exit_reason = KVM_EXIT_SYSTEM_EVENT; 2827 vcpu->run->system_event.type = KVM_SYSTEM_EVENT_SEV_TERM; 2828 vcpu->run->system_event.ndata = 1; 2829 vcpu->run->system_event.data[0] = control->ghcb_gpa; 2830 2831 return 0; 2832 } 2833 default: 2834 /* Error, keep GHCB MSR value as-is */ 2835 break; 2836 } 2837 2838 trace_kvm_vmgexit_msr_protocol_exit(svm->vcpu.vcpu_id, 2839 control->ghcb_gpa, ret); 2840 2841 return ret; 2842 } 2843 2844 int sev_handle_vmgexit(struct kvm_vcpu *vcpu) 2845 { 2846 struct vcpu_svm *svm = to_svm(vcpu); 2847 struct vmcb_control_area *control = &svm->vmcb->control; 2848 u64 ghcb_gpa, exit_code; 2849 int ret; 2850 2851 /* Validate the GHCB */ 2852 ghcb_gpa = control->ghcb_gpa; 2853 if (ghcb_gpa & GHCB_MSR_INFO_MASK) 2854 return sev_handle_vmgexit_msr_protocol(svm); 2855 2856 if (!ghcb_gpa) { 2857 vcpu_unimpl(vcpu, "vmgexit: GHCB gpa is not set\n"); 2858 2859 /* Without a GHCB, just return right back to the guest */ 2860 return 1; 2861 } 2862 2863 if (kvm_vcpu_map(vcpu, ghcb_gpa >> PAGE_SHIFT, &svm->sev_es.ghcb_map)) { 2864 /* Unable to map GHCB from guest */ 2865 vcpu_unimpl(vcpu, "vmgexit: error mapping GHCB [%#llx] from guest\n", 2866 ghcb_gpa); 2867 2868 /* Without a GHCB, just return right back to the guest */ 2869 return 1; 2870 } 2871 2872 svm->sev_es.ghcb = svm->sev_es.ghcb_map.hva; 2873 2874 trace_kvm_vmgexit_enter(vcpu->vcpu_id, svm->sev_es.ghcb); 2875 2876 sev_es_sync_from_ghcb(svm); 2877 ret = sev_es_validate_vmgexit(svm); 2878 if (ret) 2879 return ret; 2880 2881 ghcb_set_sw_exit_info_1(svm->sev_es.ghcb, 0); 2882 ghcb_set_sw_exit_info_2(svm->sev_es.ghcb, 0); 2883 2884 exit_code = kvm_ghcb_get_sw_exit_code(control); 2885 switch (exit_code) { 2886 case SVM_VMGEXIT_MMIO_READ: 2887 ret = setup_vmgexit_scratch(svm, true, control->exit_info_2); 2888 if (ret) 2889 break; 2890 2891 ret = kvm_sev_es_mmio_read(vcpu, 2892 control->exit_info_1, 2893 control->exit_info_2, 2894 svm->sev_es.ghcb_sa); 2895 break; 2896 case SVM_VMGEXIT_MMIO_WRITE: 2897 ret = setup_vmgexit_scratch(svm, false, control->exit_info_2); 2898 if (ret) 2899 break; 2900 2901 ret = kvm_sev_es_mmio_write(vcpu, 2902 control->exit_info_1, 2903 control->exit_info_2, 2904 svm->sev_es.ghcb_sa); 2905 break; 2906 case SVM_VMGEXIT_NMI_COMPLETE: 2907 ++vcpu->stat.nmi_window_exits; 2908 svm->nmi_masked = false; 2909 kvm_make_request(KVM_REQ_EVENT, vcpu); 2910 ret = 1; 2911 break; 2912 case SVM_VMGEXIT_AP_HLT_LOOP: 2913 ret = kvm_emulate_ap_reset_hold(vcpu); 2914 break; 2915 case SVM_VMGEXIT_AP_JUMP_TABLE: { 2916 struct kvm_sev_info *sev = &to_kvm_svm(vcpu->kvm)->sev_info; 2917 2918 switch (control->exit_info_1) { 2919 case 0: 2920 /* Set AP jump table address */ 2921 sev->ap_jump_table = control->exit_info_2; 2922 break; 2923 case 1: 2924 /* Get AP jump table address */ 2925 ghcb_set_sw_exit_info_2(svm->sev_es.ghcb, sev->ap_jump_table); 2926 break; 2927 default: 2928 pr_err("svm: vmgexit: unsupported AP jump table request - exit_info_1=%#llx\n", 2929 control->exit_info_1); 2930 ghcb_set_sw_exit_info_1(svm->sev_es.ghcb, 2); 2931 ghcb_set_sw_exit_info_2(svm->sev_es.ghcb, GHCB_ERR_INVALID_INPUT); 2932 } 2933 2934 ret = 1; 2935 break; 2936 } 2937 case SVM_VMGEXIT_UNSUPPORTED_EVENT: 2938 vcpu_unimpl(vcpu, 2939 "vmgexit: unsupported event - exit_info_1=%#llx, exit_info_2=%#llx\n", 2940 control->exit_info_1, control->exit_info_2); 2941 ret = -EINVAL; 2942 break; 2943 default: 2944 ret = svm_invoke_exit_handler(vcpu, exit_code); 2945 } 2946 2947 return ret; 2948 } 2949 2950 int sev_es_string_io(struct vcpu_svm *svm, int size, unsigned int port, int in) 2951 { 2952 int count; 2953 int bytes; 2954 int r; 2955 2956 if (svm->vmcb->control.exit_info_2 > INT_MAX) 2957 return -EINVAL; 2958 2959 count = svm->vmcb->control.exit_info_2; 2960 if (unlikely(check_mul_overflow(count, size, &bytes))) 2961 return -EINVAL; 2962 2963 r = setup_vmgexit_scratch(svm, in, bytes); 2964 if (r) 2965 return r; 2966 2967 return kvm_sev_es_string_io(&svm->vcpu, size, port, svm->sev_es.ghcb_sa, 2968 count, in); 2969 } 2970 2971 static void sev_es_vcpu_after_set_cpuid(struct vcpu_svm *svm) 2972 { 2973 struct kvm_vcpu *vcpu = &svm->vcpu; 2974 2975 if (boot_cpu_has(X86_FEATURE_V_TSC_AUX)) { 2976 bool v_tsc_aux = guest_cpuid_has(vcpu, X86_FEATURE_RDTSCP) || 2977 guest_cpuid_has(vcpu, X86_FEATURE_RDPID); 2978 2979 set_msr_interception(vcpu, svm->msrpm, MSR_TSC_AUX, v_tsc_aux, v_tsc_aux); 2980 } 2981 2982 /* 2983 * For SEV-ES, accesses to MSR_IA32_XSS should not be intercepted if 2984 * the host/guest supports its use. 2985 * 2986 * guest_can_use() checks a number of requirements on the host/guest to 2987 * ensure that MSR_IA32_XSS is available, but it might report true even 2988 * if X86_FEATURE_XSAVES isn't configured in the guest to ensure host 2989 * MSR_IA32_XSS is always properly restored. For SEV-ES, it is better 2990 * to further check that the guest CPUID actually supports 2991 * X86_FEATURE_XSAVES so that accesses to MSR_IA32_XSS by misbehaved 2992 * guests will still get intercepted and caught in the normal 2993 * kvm_emulate_rdmsr()/kvm_emulated_wrmsr() paths. 2994 */ 2995 if (guest_can_use(vcpu, X86_FEATURE_XSAVES) && 2996 guest_cpuid_has(vcpu, X86_FEATURE_XSAVES)) 2997 set_msr_interception(vcpu, svm->msrpm, MSR_IA32_XSS, 1, 1); 2998 else 2999 set_msr_interception(vcpu, svm->msrpm, MSR_IA32_XSS, 0, 0); 3000 } 3001 3002 void sev_vcpu_after_set_cpuid(struct vcpu_svm *svm) 3003 { 3004 struct kvm_vcpu *vcpu = &svm->vcpu; 3005 struct kvm_cpuid_entry2 *best; 3006 3007 /* For sev guests, the memory encryption bit is not reserved in CR3. */ 3008 best = kvm_find_cpuid_entry(vcpu, 0x8000001F); 3009 if (best) 3010 vcpu->arch.reserved_gpa_bits &= ~(1UL << (best->ebx & 0x3f)); 3011 3012 if (sev_es_guest(svm->vcpu.kvm)) 3013 sev_es_vcpu_after_set_cpuid(svm); 3014 } 3015 3016 static void sev_es_init_vmcb(struct vcpu_svm *svm) 3017 { 3018 struct vmcb *vmcb = svm->vmcb01.ptr; 3019 struct kvm_vcpu *vcpu = &svm->vcpu; 3020 3021 svm->vmcb->control.nested_ctl |= SVM_NESTED_CTL_SEV_ES_ENABLE; 3022 svm->vmcb->control.virt_ext |= LBR_CTL_ENABLE_MASK; 3023 3024 /* 3025 * An SEV-ES guest requires a VMSA area that is a separate from the 3026 * VMCB page. Do not include the encryption mask on the VMSA physical 3027 * address since hardware will access it using the guest key. Note, 3028 * the VMSA will be NULL if this vCPU is the destination for intrahost 3029 * migration, and will be copied later. 3030 */ 3031 if (svm->sev_es.vmsa) 3032 svm->vmcb->control.vmsa_pa = __pa(svm->sev_es.vmsa); 3033 3034 /* Can't intercept CR register access, HV can't modify CR registers */ 3035 svm_clr_intercept(svm, INTERCEPT_CR0_READ); 3036 svm_clr_intercept(svm, INTERCEPT_CR4_READ); 3037 svm_clr_intercept(svm, INTERCEPT_CR8_READ); 3038 svm_clr_intercept(svm, INTERCEPT_CR0_WRITE); 3039 svm_clr_intercept(svm, INTERCEPT_CR4_WRITE); 3040 svm_clr_intercept(svm, INTERCEPT_CR8_WRITE); 3041 3042 svm_clr_intercept(svm, INTERCEPT_SELECTIVE_CR0); 3043 3044 /* Track EFER/CR register changes */ 3045 svm_set_intercept(svm, TRAP_EFER_WRITE); 3046 svm_set_intercept(svm, TRAP_CR0_WRITE); 3047 svm_set_intercept(svm, TRAP_CR4_WRITE); 3048 svm_set_intercept(svm, TRAP_CR8_WRITE); 3049 3050 vmcb->control.intercepts[INTERCEPT_DR] = 0; 3051 if (!sev_es_debug_swap_enabled) { 3052 vmcb_set_intercept(&vmcb->control, INTERCEPT_DR7_READ); 3053 vmcb_set_intercept(&vmcb->control, INTERCEPT_DR7_WRITE); 3054 recalc_intercepts(svm); 3055 } else { 3056 /* 3057 * Disable #DB intercept iff DebugSwap is enabled. KVM doesn't 3058 * allow debugging SEV-ES guests, and enables DebugSwap iff 3059 * NO_NESTED_DATA_BP is supported, so there's no reason to 3060 * intercept #DB when DebugSwap is enabled. For simplicity 3061 * with respect to guest debug, intercept #DB for other VMs 3062 * even if NO_NESTED_DATA_BP is supported, i.e. even if the 3063 * guest can't DoS the CPU with infinite #DB vectoring. 3064 */ 3065 clr_exception_intercept(svm, DB_VECTOR); 3066 } 3067 3068 /* Can't intercept XSETBV, HV can't modify XCR0 directly */ 3069 svm_clr_intercept(svm, INTERCEPT_XSETBV); 3070 3071 /* Clear intercepts on selected MSRs */ 3072 set_msr_interception(vcpu, svm->msrpm, MSR_EFER, 1, 1); 3073 set_msr_interception(vcpu, svm->msrpm, MSR_IA32_CR_PAT, 1, 1); 3074 set_msr_interception(vcpu, svm->msrpm, MSR_IA32_LASTBRANCHFROMIP, 1, 1); 3075 set_msr_interception(vcpu, svm->msrpm, MSR_IA32_LASTBRANCHTOIP, 1, 1); 3076 set_msr_interception(vcpu, svm->msrpm, MSR_IA32_LASTINTFROMIP, 1, 1); 3077 set_msr_interception(vcpu, svm->msrpm, MSR_IA32_LASTINTTOIP, 1, 1); 3078 } 3079 3080 void sev_init_vmcb(struct vcpu_svm *svm) 3081 { 3082 svm->vmcb->control.nested_ctl |= SVM_NESTED_CTL_SEV_ENABLE; 3083 clr_exception_intercept(svm, UD_VECTOR); 3084 3085 /* 3086 * Don't intercept #GP for SEV guests, e.g. for the VMware backdoor, as 3087 * KVM can't decrypt guest memory to decode the faulting instruction. 3088 */ 3089 clr_exception_intercept(svm, GP_VECTOR); 3090 3091 if (sev_es_guest(svm->vcpu.kvm)) 3092 sev_es_init_vmcb(svm); 3093 } 3094 3095 void sev_es_vcpu_reset(struct vcpu_svm *svm) 3096 { 3097 /* 3098 * Set the GHCB MSR value as per the GHCB specification when emulating 3099 * vCPU RESET for an SEV-ES guest. 3100 */ 3101 set_ghcb_msr(svm, GHCB_MSR_SEV_INFO(GHCB_VERSION_MAX, 3102 GHCB_VERSION_MIN, 3103 sev_enc_bit)); 3104 } 3105 3106 void sev_es_prepare_switch_to_guest(struct sev_es_save_area *hostsa) 3107 { 3108 /* 3109 * All host state for SEV-ES guests is categorized into three swap types 3110 * based on how it is handled by hardware during a world switch: 3111 * 3112 * A: VMRUN: Host state saved in host save area 3113 * VMEXIT: Host state loaded from host save area 3114 * 3115 * B: VMRUN: Host state _NOT_ saved in host save area 3116 * VMEXIT: Host state loaded from host save area 3117 * 3118 * C: VMRUN: Host state _NOT_ saved in host save area 3119 * VMEXIT: Host state initialized to default(reset) values 3120 * 3121 * Manually save type-B state, i.e. state that is loaded by VMEXIT but 3122 * isn't saved by VMRUN, that isn't already saved by VMSAVE (performed 3123 * by common SVM code). 3124 */ 3125 hostsa->xcr0 = xgetbv(XCR_XFEATURE_ENABLED_MASK); 3126 hostsa->pkru = read_pkru(); 3127 hostsa->xss = host_xss; 3128 3129 /* 3130 * If DebugSwap is enabled, debug registers are loaded but NOT saved by 3131 * the CPU (Type-B). If DebugSwap is disabled/unsupported, the CPU both 3132 * saves and loads debug registers (Type-A). 3133 */ 3134 if (sev_es_debug_swap_enabled) { 3135 hostsa->dr0 = native_get_debugreg(0); 3136 hostsa->dr1 = native_get_debugreg(1); 3137 hostsa->dr2 = native_get_debugreg(2); 3138 hostsa->dr3 = native_get_debugreg(3); 3139 hostsa->dr0_addr_mask = amd_get_dr_addr_mask(0); 3140 hostsa->dr1_addr_mask = amd_get_dr_addr_mask(1); 3141 hostsa->dr2_addr_mask = amd_get_dr_addr_mask(2); 3142 hostsa->dr3_addr_mask = amd_get_dr_addr_mask(3); 3143 } 3144 } 3145 3146 void sev_vcpu_deliver_sipi_vector(struct kvm_vcpu *vcpu, u8 vector) 3147 { 3148 struct vcpu_svm *svm = to_svm(vcpu); 3149 3150 /* First SIPI: Use the values as initially set by the VMM */ 3151 if (!svm->sev_es.received_first_sipi) { 3152 svm->sev_es.received_first_sipi = true; 3153 return; 3154 } 3155 3156 /* 3157 * Subsequent SIPI: Return from an AP Reset Hold VMGEXIT, where 3158 * the guest will set the CS and RIP. Set SW_EXIT_INFO_2 to a 3159 * non-zero value. 3160 */ 3161 if (!svm->sev_es.ghcb) 3162 return; 3163 3164 ghcb_set_sw_exit_info_2(svm->sev_es.ghcb, 1); 3165 } 3166 3167 struct page *snp_safe_alloc_page(struct kvm_vcpu *vcpu) 3168 { 3169 unsigned long pfn; 3170 struct page *p; 3171 3172 if (!cpu_feature_enabled(X86_FEATURE_SEV_SNP)) 3173 return alloc_page(GFP_KERNEL_ACCOUNT | __GFP_ZERO); 3174 3175 /* 3176 * Allocate an SNP-safe page to workaround the SNP erratum where 3177 * the CPU will incorrectly signal an RMP violation #PF if a 3178 * hugepage (2MB or 1GB) collides with the RMP entry of a 3179 * 2MB-aligned VMCB, VMSA, or AVIC backing page. 3180 * 3181 * Allocate one extra page, choose a page which is not 3182 * 2MB-aligned, and free the other. 3183 */ 3184 p = alloc_pages(GFP_KERNEL_ACCOUNT | __GFP_ZERO, 1); 3185 if (!p) 3186 return NULL; 3187 3188 split_page(p, 1); 3189 3190 pfn = page_to_pfn(p); 3191 if (IS_ALIGNED(pfn, PTRS_PER_PMD)) 3192 __free_page(p++); 3193 else 3194 __free_page(p + 1); 3195 3196 return p; 3197 } 3198