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 10 #include <linux/kvm_types.h> 11 #include <linux/kvm_host.h> 12 #include <linux/kernel.h> 13 #include <linux/highmem.h> 14 #include <linux/psp-sev.h> 15 #include <linux/pagemap.h> 16 #include <linux/swap.h> 17 #include <linux/misc_cgroup.h> 18 #include <linux/processor.h> 19 #include <linux/trace_events.h> 20 21 #include <asm/pkru.h> 22 #include <asm/trapnr.h> 23 #include <asm/fpu/xcr.h> 24 25 #include "x86.h" 26 #include "svm.h" 27 #include "svm_ops.h" 28 #include "cpuid.h" 29 #include "trace.h" 30 31 #ifndef CONFIG_KVM_AMD_SEV 32 /* 33 * When this config is not defined, SEV feature is not supported and APIs in 34 * this file are not used but this file still gets compiled into the KVM AMD 35 * module. 36 * 37 * We will not have MISC_CG_RES_SEV and MISC_CG_RES_SEV_ES entries in the enum 38 * misc_res_type {} defined in linux/misc_cgroup.h. 39 * 40 * Below macros allow compilation to succeed. 41 */ 42 #define MISC_CG_RES_SEV MISC_CG_RES_TYPES 43 #define MISC_CG_RES_SEV_ES MISC_CG_RES_TYPES 44 #endif 45 46 #ifdef CONFIG_KVM_AMD_SEV 47 /* enable/disable SEV support */ 48 static bool sev_enabled = true; 49 module_param_named(sev, sev_enabled, bool, 0444); 50 51 /* enable/disable SEV-ES support */ 52 static bool sev_es_enabled = true; 53 module_param_named(sev_es, sev_es_enabled, bool, 0444); 54 #else 55 #define sev_enabled false 56 #define sev_es_enabled false 57 #endif /* CONFIG_KVM_AMD_SEV */ 58 59 static u8 sev_enc_bit; 60 static DECLARE_RWSEM(sev_deactivate_lock); 61 static DEFINE_MUTEX(sev_bitmap_lock); 62 unsigned int max_sev_asid; 63 static unsigned int min_sev_asid; 64 static unsigned long sev_me_mask; 65 static unsigned int nr_asids; 66 static unsigned long *sev_asid_bitmap; 67 static unsigned long *sev_reclaim_asid_bitmap; 68 69 struct enc_region { 70 struct list_head list; 71 unsigned long npages; 72 struct page **pages; 73 unsigned long uaddr; 74 unsigned long size; 75 }; 76 77 /* Called with the sev_bitmap_lock held, or on shutdown */ 78 static int sev_flush_asids(int min_asid, int max_asid) 79 { 80 int ret, asid, error = 0; 81 82 /* Check if there are any ASIDs to reclaim before performing a flush */ 83 asid = find_next_bit(sev_reclaim_asid_bitmap, nr_asids, min_asid); 84 if (asid > max_asid) 85 return -EBUSY; 86 87 /* 88 * DEACTIVATE will clear the WBINVD indicator causing DF_FLUSH to fail, 89 * so it must be guarded. 90 */ 91 down_write(&sev_deactivate_lock); 92 93 wbinvd_on_all_cpus(); 94 ret = sev_guest_df_flush(&error); 95 96 up_write(&sev_deactivate_lock); 97 98 if (ret) 99 pr_err("SEV: DF_FLUSH failed, ret=%d, error=%#x\n", ret, error); 100 101 return ret; 102 } 103 104 static inline bool is_mirroring_enc_context(struct kvm *kvm) 105 { 106 return !!to_kvm_svm(kvm)->sev_info.enc_context_owner; 107 } 108 109 /* Must be called with the sev_bitmap_lock held */ 110 static bool __sev_recycle_asids(int min_asid, int max_asid) 111 { 112 if (sev_flush_asids(min_asid, max_asid)) 113 return false; 114 115 /* The flush process will flush all reclaimable SEV and SEV-ES ASIDs */ 116 bitmap_xor(sev_asid_bitmap, sev_asid_bitmap, sev_reclaim_asid_bitmap, 117 nr_asids); 118 bitmap_zero(sev_reclaim_asid_bitmap, nr_asids); 119 120 return true; 121 } 122 123 static int sev_misc_cg_try_charge(struct kvm_sev_info *sev) 124 { 125 enum misc_res_type type = sev->es_active ? MISC_CG_RES_SEV_ES : MISC_CG_RES_SEV; 126 return misc_cg_try_charge(type, sev->misc_cg, 1); 127 } 128 129 static void sev_misc_cg_uncharge(struct kvm_sev_info *sev) 130 { 131 enum misc_res_type type = sev->es_active ? MISC_CG_RES_SEV_ES : MISC_CG_RES_SEV; 132 misc_cg_uncharge(type, sev->misc_cg, 1); 133 } 134 135 static int sev_asid_new(struct kvm_sev_info *sev) 136 { 137 int asid, min_asid, max_asid, ret; 138 bool retry = true; 139 140 WARN_ON(sev->misc_cg); 141 sev->misc_cg = get_current_misc_cg(); 142 ret = sev_misc_cg_try_charge(sev); 143 if (ret) { 144 put_misc_cg(sev->misc_cg); 145 sev->misc_cg = NULL; 146 return ret; 147 } 148 149 mutex_lock(&sev_bitmap_lock); 150 151 /* 152 * SEV-enabled guests must use asid from min_sev_asid to max_sev_asid. 153 * SEV-ES-enabled guest can use from 1 to min_sev_asid - 1. 154 */ 155 min_asid = sev->es_active ? 1 : min_sev_asid; 156 max_asid = sev->es_active ? min_sev_asid - 1 : max_sev_asid; 157 again: 158 asid = find_next_zero_bit(sev_asid_bitmap, max_asid + 1, min_asid); 159 if (asid > max_asid) { 160 if (retry && __sev_recycle_asids(min_asid, max_asid)) { 161 retry = false; 162 goto again; 163 } 164 mutex_unlock(&sev_bitmap_lock); 165 ret = -EBUSY; 166 goto e_uncharge; 167 } 168 169 __set_bit(asid, sev_asid_bitmap); 170 171 mutex_unlock(&sev_bitmap_lock); 172 173 return asid; 174 e_uncharge: 175 sev_misc_cg_uncharge(sev); 176 put_misc_cg(sev->misc_cg); 177 sev->misc_cg = NULL; 178 return ret; 179 } 180 181 static int sev_get_asid(struct kvm *kvm) 182 { 183 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 184 185 return sev->asid; 186 } 187 188 static void sev_asid_free(struct kvm_sev_info *sev) 189 { 190 struct svm_cpu_data *sd; 191 int cpu; 192 193 mutex_lock(&sev_bitmap_lock); 194 195 __set_bit(sev->asid, sev_reclaim_asid_bitmap); 196 197 for_each_possible_cpu(cpu) { 198 sd = per_cpu(svm_data, cpu); 199 sd->sev_vmcbs[sev->asid] = NULL; 200 } 201 202 mutex_unlock(&sev_bitmap_lock); 203 204 sev_misc_cg_uncharge(sev); 205 put_misc_cg(sev->misc_cg); 206 sev->misc_cg = NULL; 207 } 208 209 static void sev_decommission(unsigned int handle) 210 { 211 struct sev_data_decommission decommission; 212 213 if (!handle) 214 return; 215 216 decommission.handle = handle; 217 sev_guest_decommission(&decommission, NULL); 218 } 219 220 static void sev_unbind_asid(struct kvm *kvm, unsigned int handle) 221 { 222 struct sev_data_deactivate deactivate; 223 224 if (!handle) 225 return; 226 227 deactivate.handle = handle; 228 229 /* Guard DEACTIVATE against WBINVD/DF_FLUSH used in ASID recycling */ 230 down_read(&sev_deactivate_lock); 231 sev_guest_deactivate(&deactivate, NULL); 232 up_read(&sev_deactivate_lock); 233 234 sev_decommission(handle); 235 } 236 237 static int sev_guest_init(struct kvm *kvm, struct kvm_sev_cmd *argp) 238 { 239 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 240 int asid, ret; 241 242 if (kvm->created_vcpus) 243 return -EINVAL; 244 245 ret = -EBUSY; 246 if (unlikely(sev->active)) 247 return ret; 248 249 sev->active = true; 250 sev->es_active = argp->id == KVM_SEV_ES_INIT; 251 asid = sev_asid_new(sev); 252 if (asid < 0) 253 goto e_no_asid; 254 sev->asid = asid; 255 256 ret = sev_platform_init(&argp->error); 257 if (ret) 258 goto e_free; 259 260 INIT_LIST_HEAD(&sev->regions_list); 261 INIT_LIST_HEAD(&sev->mirror_vms); 262 263 kvm_set_apicv_inhibit(kvm, APICV_INHIBIT_REASON_SEV); 264 265 return 0; 266 267 e_free: 268 sev_asid_free(sev); 269 sev->asid = 0; 270 e_no_asid: 271 sev->es_active = false; 272 sev->active = false; 273 return ret; 274 } 275 276 static int sev_bind_asid(struct kvm *kvm, unsigned int handle, int *error) 277 { 278 struct sev_data_activate activate; 279 int asid = sev_get_asid(kvm); 280 int ret; 281 282 /* activate ASID on the given handle */ 283 activate.handle = handle; 284 activate.asid = asid; 285 ret = sev_guest_activate(&activate, error); 286 287 return ret; 288 } 289 290 static int __sev_issue_cmd(int fd, int id, void *data, int *error) 291 { 292 struct fd f; 293 int ret; 294 295 f = fdget(fd); 296 if (!f.file) 297 return -EBADF; 298 299 ret = sev_issue_cmd_external_user(f.file, id, data, error); 300 301 fdput(f); 302 return ret; 303 } 304 305 static int sev_issue_cmd(struct kvm *kvm, int id, void *data, int *error) 306 { 307 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 308 309 return __sev_issue_cmd(sev->fd, id, data, error); 310 } 311 312 static int sev_launch_start(struct kvm *kvm, struct kvm_sev_cmd *argp) 313 { 314 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 315 struct sev_data_launch_start start; 316 struct kvm_sev_launch_start params; 317 void *dh_blob, *session_blob; 318 int *error = &argp->error; 319 int ret; 320 321 if (!sev_guest(kvm)) 322 return -ENOTTY; 323 324 if (copy_from_user(¶ms, (void __user *)(uintptr_t)argp->data, sizeof(params))) 325 return -EFAULT; 326 327 memset(&start, 0, sizeof(start)); 328 329 dh_blob = NULL; 330 if (params.dh_uaddr) { 331 dh_blob = psp_copy_user_blob(params.dh_uaddr, params.dh_len); 332 if (IS_ERR(dh_blob)) 333 return PTR_ERR(dh_blob); 334 335 start.dh_cert_address = __sme_set(__pa(dh_blob)); 336 start.dh_cert_len = params.dh_len; 337 } 338 339 session_blob = NULL; 340 if (params.session_uaddr) { 341 session_blob = psp_copy_user_blob(params.session_uaddr, params.session_len); 342 if (IS_ERR(session_blob)) { 343 ret = PTR_ERR(session_blob); 344 goto e_free_dh; 345 } 346 347 start.session_address = __sme_set(__pa(session_blob)); 348 start.session_len = params.session_len; 349 } 350 351 start.handle = params.handle; 352 start.policy = params.policy; 353 354 /* create memory encryption context */ 355 ret = __sev_issue_cmd(argp->sev_fd, SEV_CMD_LAUNCH_START, &start, error); 356 if (ret) 357 goto e_free_session; 358 359 /* Bind ASID to this guest */ 360 ret = sev_bind_asid(kvm, start.handle, error); 361 if (ret) { 362 sev_decommission(start.handle); 363 goto e_free_session; 364 } 365 366 /* return handle to userspace */ 367 params.handle = start.handle; 368 if (copy_to_user((void __user *)(uintptr_t)argp->data, ¶ms, sizeof(params))) { 369 sev_unbind_asid(kvm, start.handle); 370 ret = -EFAULT; 371 goto e_free_session; 372 } 373 374 sev->handle = start.handle; 375 sev->fd = argp->sev_fd; 376 377 e_free_session: 378 kfree(session_blob); 379 e_free_dh: 380 kfree(dh_blob); 381 return ret; 382 } 383 384 static struct page **sev_pin_memory(struct kvm *kvm, unsigned long uaddr, 385 unsigned long ulen, unsigned long *n, 386 int write) 387 { 388 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 389 unsigned long npages, size; 390 int npinned; 391 unsigned long locked, lock_limit; 392 struct page **pages; 393 unsigned long first, last; 394 int ret; 395 396 lockdep_assert_held(&kvm->lock); 397 398 if (ulen == 0 || uaddr + ulen < uaddr) 399 return ERR_PTR(-EINVAL); 400 401 /* Calculate number of pages. */ 402 first = (uaddr & PAGE_MASK) >> PAGE_SHIFT; 403 last = ((uaddr + ulen - 1) & PAGE_MASK) >> PAGE_SHIFT; 404 npages = (last - first + 1); 405 406 locked = sev->pages_locked + npages; 407 lock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT; 408 if (locked > lock_limit && !capable(CAP_IPC_LOCK)) { 409 pr_err("SEV: %lu locked pages exceed the lock limit of %lu.\n", locked, lock_limit); 410 return ERR_PTR(-ENOMEM); 411 } 412 413 if (WARN_ON_ONCE(npages > INT_MAX)) 414 return ERR_PTR(-EINVAL); 415 416 /* Avoid using vmalloc for smaller buffers. */ 417 size = npages * sizeof(struct page *); 418 if (size > PAGE_SIZE) 419 pages = __vmalloc(size, GFP_KERNEL_ACCOUNT | __GFP_ZERO); 420 else 421 pages = kmalloc(size, GFP_KERNEL_ACCOUNT); 422 423 if (!pages) 424 return ERR_PTR(-ENOMEM); 425 426 /* Pin the user virtual address. */ 427 npinned = pin_user_pages_fast(uaddr, npages, write ? FOLL_WRITE : 0, pages); 428 if (npinned != npages) { 429 pr_err("SEV: Failure locking %lu pages.\n", npages); 430 ret = -ENOMEM; 431 goto err; 432 } 433 434 *n = npages; 435 sev->pages_locked = locked; 436 437 return pages; 438 439 err: 440 if (npinned > 0) 441 unpin_user_pages(pages, npinned); 442 443 kvfree(pages); 444 return ERR_PTR(ret); 445 } 446 447 static void sev_unpin_memory(struct kvm *kvm, struct page **pages, 448 unsigned long npages) 449 { 450 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 451 452 unpin_user_pages(pages, npages); 453 kvfree(pages); 454 sev->pages_locked -= npages; 455 } 456 457 static void sev_clflush_pages(struct page *pages[], unsigned long npages) 458 { 459 uint8_t *page_virtual; 460 unsigned long i; 461 462 if (this_cpu_has(X86_FEATURE_SME_COHERENT) || npages == 0 || 463 pages == NULL) 464 return; 465 466 for (i = 0; i < npages; i++) { 467 page_virtual = kmap_atomic(pages[i]); 468 clflush_cache_range(page_virtual, PAGE_SIZE); 469 kunmap_atomic(page_virtual); 470 cond_resched(); 471 } 472 } 473 474 static unsigned long get_num_contig_pages(unsigned long idx, 475 struct page **inpages, unsigned long npages) 476 { 477 unsigned long paddr, next_paddr; 478 unsigned long i = idx + 1, pages = 1; 479 480 /* find the number of contiguous pages starting from idx */ 481 paddr = __sme_page_pa(inpages[idx]); 482 while (i < npages) { 483 next_paddr = __sme_page_pa(inpages[i++]); 484 if ((paddr + PAGE_SIZE) == next_paddr) { 485 pages++; 486 paddr = next_paddr; 487 continue; 488 } 489 break; 490 } 491 492 return pages; 493 } 494 495 static int sev_launch_update_data(struct kvm *kvm, struct kvm_sev_cmd *argp) 496 { 497 unsigned long vaddr, vaddr_end, next_vaddr, npages, pages, size, i; 498 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 499 struct kvm_sev_launch_update_data params; 500 struct sev_data_launch_update_data data; 501 struct page **inpages; 502 int ret; 503 504 if (!sev_guest(kvm)) 505 return -ENOTTY; 506 507 if (copy_from_user(¶ms, (void __user *)(uintptr_t)argp->data, sizeof(params))) 508 return -EFAULT; 509 510 vaddr = params.uaddr; 511 size = params.len; 512 vaddr_end = vaddr + size; 513 514 /* Lock the user memory. */ 515 inpages = sev_pin_memory(kvm, vaddr, size, &npages, 1); 516 if (IS_ERR(inpages)) 517 return PTR_ERR(inpages); 518 519 /* 520 * Flush (on non-coherent CPUs) before LAUNCH_UPDATE encrypts pages in 521 * place; the cache may contain the data that was written unencrypted. 522 */ 523 sev_clflush_pages(inpages, npages); 524 525 data.reserved = 0; 526 data.handle = sev->handle; 527 528 for (i = 0; vaddr < vaddr_end; vaddr = next_vaddr, i += pages) { 529 int offset, len; 530 531 /* 532 * If the user buffer is not page-aligned, calculate the offset 533 * within the page. 534 */ 535 offset = vaddr & (PAGE_SIZE - 1); 536 537 /* Calculate the number of pages that can be encrypted in one go. */ 538 pages = get_num_contig_pages(i, inpages, npages); 539 540 len = min_t(size_t, ((pages * PAGE_SIZE) - offset), size); 541 542 data.len = len; 543 data.address = __sme_page_pa(inpages[i]) + offset; 544 ret = sev_issue_cmd(kvm, SEV_CMD_LAUNCH_UPDATE_DATA, &data, &argp->error); 545 if (ret) 546 goto e_unpin; 547 548 size -= len; 549 next_vaddr = vaddr + len; 550 } 551 552 e_unpin: 553 /* content of memory is updated, mark pages dirty */ 554 for (i = 0; i < npages; i++) { 555 set_page_dirty_lock(inpages[i]); 556 mark_page_accessed(inpages[i]); 557 } 558 /* unlock the user pages */ 559 sev_unpin_memory(kvm, inpages, npages); 560 return ret; 561 } 562 563 static int sev_es_sync_vmsa(struct vcpu_svm *svm) 564 { 565 struct vmcb_save_area *save = &svm->vmcb->save; 566 567 /* Check some debug related fields before encrypting the VMSA */ 568 if (svm->vcpu.guest_debug || (save->dr7 & ~DR7_FIXED_1)) 569 return -EINVAL; 570 571 /* Sync registgers */ 572 save->rax = svm->vcpu.arch.regs[VCPU_REGS_RAX]; 573 save->rbx = svm->vcpu.arch.regs[VCPU_REGS_RBX]; 574 save->rcx = svm->vcpu.arch.regs[VCPU_REGS_RCX]; 575 save->rdx = svm->vcpu.arch.regs[VCPU_REGS_RDX]; 576 save->rsp = svm->vcpu.arch.regs[VCPU_REGS_RSP]; 577 save->rbp = svm->vcpu.arch.regs[VCPU_REGS_RBP]; 578 save->rsi = svm->vcpu.arch.regs[VCPU_REGS_RSI]; 579 save->rdi = svm->vcpu.arch.regs[VCPU_REGS_RDI]; 580 #ifdef CONFIG_X86_64 581 save->r8 = svm->vcpu.arch.regs[VCPU_REGS_R8]; 582 save->r9 = svm->vcpu.arch.regs[VCPU_REGS_R9]; 583 save->r10 = svm->vcpu.arch.regs[VCPU_REGS_R10]; 584 save->r11 = svm->vcpu.arch.regs[VCPU_REGS_R11]; 585 save->r12 = svm->vcpu.arch.regs[VCPU_REGS_R12]; 586 save->r13 = svm->vcpu.arch.regs[VCPU_REGS_R13]; 587 save->r14 = svm->vcpu.arch.regs[VCPU_REGS_R14]; 588 save->r15 = svm->vcpu.arch.regs[VCPU_REGS_R15]; 589 #endif 590 save->rip = svm->vcpu.arch.regs[VCPU_REGS_RIP]; 591 592 /* Sync some non-GPR registers before encrypting */ 593 save->xcr0 = svm->vcpu.arch.xcr0; 594 save->pkru = svm->vcpu.arch.pkru; 595 save->xss = svm->vcpu.arch.ia32_xss; 596 save->dr6 = svm->vcpu.arch.dr6; 597 598 /* 599 * SEV-ES will use a VMSA that is pointed to by the VMCB, not 600 * the traditional VMSA that is part of the VMCB. Copy the 601 * traditional VMSA as it has been built so far (in prep 602 * for LAUNCH_UPDATE_VMSA) to be the initial SEV-ES state. 603 */ 604 memcpy(svm->sev_es.vmsa, save, sizeof(*save)); 605 606 return 0; 607 } 608 609 static int __sev_launch_update_vmsa(struct kvm *kvm, struct kvm_vcpu *vcpu, 610 int *error) 611 { 612 struct sev_data_launch_update_vmsa vmsa; 613 struct vcpu_svm *svm = to_svm(vcpu); 614 int ret; 615 616 /* Perform some pre-encryption checks against the VMSA */ 617 ret = sev_es_sync_vmsa(svm); 618 if (ret) 619 return ret; 620 621 /* 622 * The LAUNCH_UPDATE_VMSA command will perform in-place encryption of 623 * the VMSA memory content (i.e it will write the same memory region 624 * with the guest's key), so invalidate it first. 625 */ 626 clflush_cache_range(svm->sev_es.vmsa, PAGE_SIZE); 627 628 vmsa.reserved = 0; 629 vmsa.handle = to_kvm_svm(kvm)->sev_info.handle; 630 vmsa.address = __sme_pa(svm->sev_es.vmsa); 631 vmsa.len = PAGE_SIZE; 632 ret = sev_issue_cmd(kvm, SEV_CMD_LAUNCH_UPDATE_VMSA, &vmsa, error); 633 if (ret) 634 return ret; 635 636 vcpu->arch.guest_state_protected = true; 637 return 0; 638 } 639 640 static int sev_launch_update_vmsa(struct kvm *kvm, struct kvm_sev_cmd *argp) 641 { 642 struct kvm_vcpu *vcpu; 643 unsigned long i; 644 int ret; 645 646 if (!sev_es_guest(kvm)) 647 return -ENOTTY; 648 649 kvm_for_each_vcpu(i, vcpu, kvm) { 650 ret = mutex_lock_killable(&vcpu->mutex); 651 if (ret) 652 return ret; 653 654 ret = __sev_launch_update_vmsa(kvm, vcpu, &argp->error); 655 656 mutex_unlock(&vcpu->mutex); 657 if (ret) 658 return ret; 659 } 660 661 return 0; 662 } 663 664 static int sev_launch_measure(struct kvm *kvm, struct kvm_sev_cmd *argp) 665 { 666 void __user *measure = (void __user *)(uintptr_t)argp->data; 667 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 668 struct sev_data_launch_measure data; 669 struct kvm_sev_launch_measure params; 670 void __user *p = NULL; 671 void *blob = NULL; 672 int ret; 673 674 if (!sev_guest(kvm)) 675 return -ENOTTY; 676 677 if (copy_from_user(¶ms, measure, sizeof(params))) 678 return -EFAULT; 679 680 memset(&data, 0, sizeof(data)); 681 682 /* User wants to query the blob length */ 683 if (!params.len) 684 goto cmd; 685 686 p = (void __user *)(uintptr_t)params.uaddr; 687 if (p) { 688 if (params.len > SEV_FW_BLOB_MAX_SIZE) 689 return -EINVAL; 690 691 blob = kmalloc(params.len, GFP_KERNEL_ACCOUNT); 692 if (!blob) 693 return -ENOMEM; 694 695 data.address = __psp_pa(blob); 696 data.len = params.len; 697 } 698 699 cmd: 700 data.handle = sev->handle; 701 ret = sev_issue_cmd(kvm, SEV_CMD_LAUNCH_MEASURE, &data, &argp->error); 702 703 /* 704 * If we query the session length, FW responded with expected data. 705 */ 706 if (!params.len) 707 goto done; 708 709 if (ret) 710 goto e_free_blob; 711 712 if (blob) { 713 if (copy_to_user(p, blob, params.len)) 714 ret = -EFAULT; 715 } 716 717 done: 718 params.len = data.len; 719 if (copy_to_user(measure, ¶ms, sizeof(params))) 720 ret = -EFAULT; 721 e_free_blob: 722 kfree(blob); 723 return ret; 724 } 725 726 static int sev_launch_finish(struct kvm *kvm, struct kvm_sev_cmd *argp) 727 { 728 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 729 struct sev_data_launch_finish data; 730 731 if (!sev_guest(kvm)) 732 return -ENOTTY; 733 734 data.handle = sev->handle; 735 return sev_issue_cmd(kvm, SEV_CMD_LAUNCH_FINISH, &data, &argp->error); 736 } 737 738 static int sev_guest_status(struct kvm *kvm, struct kvm_sev_cmd *argp) 739 { 740 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 741 struct kvm_sev_guest_status params; 742 struct sev_data_guest_status data; 743 int ret; 744 745 if (!sev_guest(kvm)) 746 return -ENOTTY; 747 748 memset(&data, 0, sizeof(data)); 749 750 data.handle = sev->handle; 751 ret = sev_issue_cmd(kvm, SEV_CMD_GUEST_STATUS, &data, &argp->error); 752 if (ret) 753 return ret; 754 755 params.policy = data.policy; 756 params.state = data.state; 757 params.handle = data.handle; 758 759 if (copy_to_user((void __user *)(uintptr_t)argp->data, ¶ms, sizeof(params))) 760 ret = -EFAULT; 761 762 return ret; 763 } 764 765 static int __sev_issue_dbg_cmd(struct kvm *kvm, unsigned long src, 766 unsigned long dst, int size, 767 int *error, bool enc) 768 { 769 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 770 struct sev_data_dbg data; 771 772 data.reserved = 0; 773 data.handle = sev->handle; 774 data.dst_addr = dst; 775 data.src_addr = src; 776 data.len = size; 777 778 return sev_issue_cmd(kvm, 779 enc ? SEV_CMD_DBG_ENCRYPT : SEV_CMD_DBG_DECRYPT, 780 &data, error); 781 } 782 783 static int __sev_dbg_decrypt(struct kvm *kvm, unsigned long src_paddr, 784 unsigned long dst_paddr, int sz, int *err) 785 { 786 int offset; 787 788 /* 789 * Its safe to read more than we are asked, caller should ensure that 790 * destination has enough space. 791 */ 792 offset = src_paddr & 15; 793 src_paddr = round_down(src_paddr, 16); 794 sz = round_up(sz + offset, 16); 795 796 return __sev_issue_dbg_cmd(kvm, src_paddr, dst_paddr, sz, err, false); 797 } 798 799 static int __sev_dbg_decrypt_user(struct kvm *kvm, unsigned long paddr, 800 void __user *dst_uaddr, 801 unsigned long dst_paddr, 802 int size, int *err) 803 { 804 struct page *tpage = NULL; 805 int ret, offset; 806 807 /* if inputs are not 16-byte then use intermediate buffer */ 808 if (!IS_ALIGNED(dst_paddr, 16) || 809 !IS_ALIGNED(paddr, 16) || 810 !IS_ALIGNED(size, 16)) { 811 tpage = (void *)alloc_page(GFP_KERNEL); 812 if (!tpage) 813 return -ENOMEM; 814 815 dst_paddr = __sme_page_pa(tpage); 816 } 817 818 ret = __sev_dbg_decrypt(kvm, paddr, dst_paddr, size, err); 819 if (ret) 820 goto e_free; 821 822 if (tpage) { 823 offset = paddr & 15; 824 if (copy_to_user(dst_uaddr, page_address(tpage) + offset, size)) 825 ret = -EFAULT; 826 } 827 828 e_free: 829 if (tpage) 830 __free_page(tpage); 831 832 return ret; 833 } 834 835 static int __sev_dbg_encrypt_user(struct kvm *kvm, unsigned long paddr, 836 void __user *vaddr, 837 unsigned long dst_paddr, 838 void __user *dst_vaddr, 839 int size, int *error) 840 { 841 struct page *src_tpage = NULL; 842 struct page *dst_tpage = NULL; 843 int ret, len = size; 844 845 /* If source buffer is not aligned then use an intermediate buffer */ 846 if (!IS_ALIGNED((unsigned long)vaddr, 16)) { 847 src_tpage = alloc_page(GFP_KERNEL); 848 if (!src_tpage) 849 return -ENOMEM; 850 851 if (copy_from_user(page_address(src_tpage), vaddr, size)) { 852 __free_page(src_tpage); 853 return -EFAULT; 854 } 855 856 paddr = __sme_page_pa(src_tpage); 857 } 858 859 /* 860 * If destination buffer or length is not aligned then do read-modify-write: 861 * - decrypt destination in an intermediate buffer 862 * - copy the source buffer in an intermediate buffer 863 * - use the intermediate buffer as source buffer 864 */ 865 if (!IS_ALIGNED((unsigned long)dst_vaddr, 16) || !IS_ALIGNED(size, 16)) { 866 int dst_offset; 867 868 dst_tpage = alloc_page(GFP_KERNEL); 869 if (!dst_tpage) { 870 ret = -ENOMEM; 871 goto e_free; 872 } 873 874 ret = __sev_dbg_decrypt(kvm, dst_paddr, 875 __sme_page_pa(dst_tpage), size, error); 876 if (ret) 877 goto e_free; 878 879 /* 880 * If source is kernel buffer then use memcpy() otherwise 881 * copy_from_user(). 882 */ 883 dst_offset = dst_paddr & 15; 884 885 if (src_tpage) 886 memcpy(page_address(dst_tpage) + dst_offset, 887 page_address(src_tpage), size); 888 else { 889 if (copy_from_user(page_address(dst_tpage) + dst_offset, 890 vaddr, size)) { 891 ret = -EFAULT; 892 goto e_free; 893 } 894 } 895 896 paddr = __sme_page_pa(dst_tpage); 897 dst_paddr = round_down(dst_paddr, 16); 898 len = round_up(size, 16); 899 } 900 901 ret = __sev_issue_dbg_cmd(kvm, paddr, dst_paddr, len, error, true); 902 903 e_free: 904 if (src_tpage) 905 __free_page(src_tpage); 906 if (dst_tpage) 907 __free_page(dst_tpage); 908 return ret; 909 } 910 911 static int sev_dbg_crypt(struct kvm *kvm, struct kvm_sev_cmd *argp, bool dec) 912 { 913 unsigned long vaddr, vaddr_end, next_vaddr; 914 unsigned long dst_vaddr; 915 struct page **src_p, **dst_p; 916 struct kvm_sev_dbg debug; 917 unsigned long n; 918 unsigned int size; 919 int ret; 920 921 if (!sev_guest(kvm)) 922 return -ENOTTY; 923 924 if (copy_from_user(&debug, (void __user *)(uintptr_t)argp->data, sizeof(debug))) 925 return -EFAULT; 926 927 if (!debug.len || debug.src_uaddr + debug.len < debug.src_uaddr) 928 return -EINVAL; 929 if (!debug.dst_uaddr) 930 return -EINVAL; 931 932 vaddr = debug.src_uaddr; 933 size = debug.len; 934 vaddr_end = vaddr + size; 935 dst_vaddr = debug.dst_uaddr; 936 937 for (; vaddr < vaddr_end; vaddr = next_vaddr) { 938 int len, s_off, d_off; 939 940 /* lock userspace source and destination page */ 941 src_p = sev_pin_memory(kvm, vaddr & PAGE_MASK, PAGE_SIZE, &n, 0); 942 if (IS_ERR(src_p)) 943 return PTR_ERR(src_p); 944 945 dst_p = sev_pin_memory(kvm, dst_vaddr & PAGE_MASK, PAGE_SIZE, &n, 1); 946 if (IS_ERR(dst_p)) { 947 sev_unpin_memory(kvm, src_p, n); 948 return PTR_ERR(dst_p); 949 } 950 951 /* 952 * Flush (on non-coherent CPUs) before DBG_{DE,EN}CRYPT read or modify 953 * the pages; flush the destination too so that future accesses do not 954 * see stale data. 955 */ 956 sev_clflush_pages(src_p, 1); 957 sev_clflush_pages(dst_p, 1); 958 959 /* 960 * Since user buffer may not be page aligned, calculate the 961 * offset within the page. 962 */ 963 s_off = vaddr & ~PAGE_MASK; 964 d_off = dst_vaddr & ~PAGE_MASK; 965 len = min_t(size_t, (PAGE_SIZE - s_off), size); 966 967 if (dec) 968 ret = __sev_dbg_decrypt_user(kvm, 969 __sme_page_pa(src_p[0]) + s_off, 970 (void __user *)dst_vaddr, 971 __sme_page_pa(dst_p[0]) + d_off, 972 len, &argp->error); 973 else 974 ret = __sev_dbg_encrypt_user(kvm, 975 __sme_page_pa(src_p[0]) + s_off, 976 (void __user *)vaddr, 977 __sme_page_pa(dst_p[0]) + d_off, 978 (void __user *)dst_vaddr, 979 len, &argp->error); 980 981 sev_unpin_memory(kvm, src_p, n); 982 sev_unpin_memory(kvm, dst_p, n); 983 984 if (ret) 985 goto err; 986 987 next_vaddr = vaddr + len; 988 dst_vaddr = dst_vaddr + len; 989 size -= len; 990 } 991 err: 992 return ret; 993 } 994 995 static int sev_launch_secret(struct kvm *kvm, struct kvm_sev_cmd *argp) 996 { 997 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 998 struct sev_data_launch_secret data; 999 struct kvm_sev_launch_secret params; 1000 struct page **pages; 1001 void *blob, *hdr; 1002 unsigned long n, i; 1003 int ret, offset; 1004 1005 if (!sev_guest(kvm)) 1006 return -ENOTTY; 1007 1008 if (copy_from_user(¶ms, (void __user *)(uintptr_t)argp->data, sizeof(params))) 1009 return -EFAULT; 1010 1011 pages = sev_pin_memory(kvm, params.guest_uaddr, params.guest_len, &n, 1); 1012 if (IS_ERR(pages)) 1013 return PTR_ERR(pages); 1014 1015 /* 1016 * Flush (on non-coherent CPUs) before LAUNCH_SECRET encrypts pages in 1017 * place; the cache may contain the data that was written unencrypted. 1018 */ 1019 sev_clflush_pages(pages, n); 1020 1021 /* 1022 * The secret must be copied into contiguous memory region, lets verify 1023 * that userspace memory pages are contiguous before we issue command. 1024 */ 1025 if (get_num_contig_pages(0, pages, n) != n) { 1026 ret = -EINVAL; 1027 goto e_unpin_memory; 1028 } 1029 1030 memset(&data, 0, sizeof(data)); 1031 1032 offset = params.guest_uaddr & (PAGE_SIZE - 1); 1033 data.guest_address = __sme_page_pa(pages[0]) + offset; 1034 data.guest_len = params.guest_len; 1035 1036 blob = psp_copy_user_blob(params.trans_uaddr, params.trans_len); 1037 if (IS_ERR(blob)) { 1038 ret = PTR_ERR(blob); 1039 goto e_unpin_memory; 1040 } 1041 1042 data.trans_address = __psp_pa(blob); 1043 data.trans_len = params.trans_len; 1044 1045 hdr = psp_copy_user_blob(params.hdr_uaddr, params.hdr_len); 1046 if (IS_ERR(hdr)) { 1047 ret = PTR_ERR(hdr); 1048 goto e_free_blob; 1049 } 1050 data.hdr_address = __psp_pa(hdr); 1051 data.hdr_len = params.hdr_len; 1052 1053 data.handle = sev->handle; 1054 ret = sev_issue_cmd(kvm, SEV_CMD_LAUNCH_UPDATE_SECRET, &data, &argp->error); 1055 1056 kfree(hdr); 1057 1058 e_free_blob: 1059 kfree(blob); 1060 e_unpin_memory: 1061 /* content of memory is updated, mark pages dirty */ 1062 for (i = 0; i < n; i++) { 1063 set_page_dirty_lock(pages[i]); 1064 mark_page_accessed(pages[i]); 1065 } 1066 sev_unpin_memory(kvm, pages, n); 1067 return ret; 1068 } 1069 1070 static int sev_get_attestation_report(struct kvm *kvm, struct kvm_sev_cmd *argp) 1071 { 1072 void __user *report = (void __user *)(uintptr_t)argp->data; 1073 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 1074 struct sev_data_attestation_report data; 1075 struct kvm_sev_attestation_report params; 1076 void __user *p; 1077 void *blob = NULL; 1078 int ret; 1079 1080 if (!sev_guest(kvm)) 1081 return -ENOTTY; 1082 1083 if (copy_from_user(¶ms, (void __user *)(uintptr_t)argp->data, sizeof(params))) 1084 return -EFAULT; 1085 1086 memset(&data, 0, sizeof(data)); 1087 1088 /* User wants to query the blob length */ 1089 if (!params.len) 1090 goto cmd; 1091 1092 p = (void __user *)(uintptr_t)params.uaddr; 1093 if (p) { 1094 if (params.len > SEV_FW_BLOB_MAX_SIZE) 1095 return -EINVAL; 1096 1097 blob = kmalloc(params.len, GFP_KERNEL_ACCOUNT); 1098 if (!blob) 1099 return -ENOMEM; 1100 1101 data.address = __psp_pa(blob); 1102 data.len = params.len; 1103 memcpy(data.mnonce, params.mnonce, sizeof(params.mnonce)); 1104 } 1105 cmd: 1106 data.handle = sev->handle; 1107 ret = sev_issue_cmd(kvm, SEV_CMD_ATTESTATION_REPORT, &data, &argp->error); 1108 /* 1109 * If we query the session length, FW responded with expected data. 1110 */ 1111 if (!params.len) 1112 goto done; 1113 1114 if (ret) 1115 goto e_free_blob; 1116 1117 if (blob) { 1118 if (copy_to_user(p, blob, params.len)) 1119 ret = -EFAULT; 1120 } 1121 1122 done: 1123 params.len = data.len; 1124 if (copy_to_user(report, ¶ms, sizeof(params))) 1125 ret = -EFAULT; 1126 e_free_blob: 1127 kfree(blob); 1128 return ret; 1129 } 1130 1131 /* Userspace wants to query session length. */ 1132 static int 1133 __sev_send_start_query_session_length(struct kvm *kvm, struct kvm_sev_cmd *argp, 1134 struct kvm_sev_send_start *params) 1135 { 1136 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 1137 struct sev_data_send_start data; 1138 int ret; 1139 1140 memset(&data, 0, sizeof(data)); 1141 data.handle = sev->handle; 1142 ret = sev_issue_cmd(kvm, SEV_CMD_SEND_START, &data, &argp->error); 1143 1144 params->session_len = data.session_len; 1145 if (copy_to_user((void __user *)(uintptr_t)argp->data, params, 1146 sizeof(struct kvm_sev_send_start))) 1147 ret = -EFAULT; 1148 1149 return ret; 1150 } 1151 1152 static int sev_send_start(struct kvm *kvm, struct kvm_sev_cmd *argp) 1153 { 1154 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 1155 struct sev_data_send_start data; 1156 struct kvm_sev_send_start params; 1157 void *amd_certs, *session_data; 1158 void *pdh_cert, *plat_certs; 1159 int ret; 1160 1161 if (!sev_guest(kvm)) 1162 return -ENOTTY; 1163 1164 if (copy_from_user(¶ms, (void __user *)(uintptr_t)argp->data, 1165 sizeof(struct kvm_sev_send_start))) 1166 return -EFAULT; 1167 1168 /* if session_len is zero, userspace wants to query the session length */ 1169 if (!params.session_len) 1170 return __sev_send_start_query_session_length(kvm, argp, 1171 ¶ms); 1172 1173 /* some sanity checks */ 1174 if (!params.pdh_cert_uaddr || !params.pdh_cert_len || 1175 !params.session_uaddr || params.session_len > SEV_FW_BLOB_MAX_SIZE) 1176 return -EINVAL; 1177 1178 /* allocate the memory to hold the session data blob */ 1179 session_data = kmalloc(params.session_len, GFP_KERNEL_ACCOUNT); 1180 if (!session_data) 1181 return -ENOMEM; 1182 1183 /* copy the certificate blobs from userspace */ 1184 pdh_cert = psp_copy_user_blob(params.pdh_cert_uaddr, 1185 params.pdh_cert_len); 1186 if (IS_ERR(pdh_cert)) { 1187 ret = PTR_ERR(pdh_cert); 1188 goto e_free_session; 1189 } 1190 1191 plat_certs = psp_copy_user_blob(params.plat_certs_uaddr, 1192 params.plat_certs_len); 1193 if (IS_ERR(plat_certs)) { 1194 ret = PTR_ERR(plat_certs); 1195 goto e_free_pdh; 1196 } 1197 1198 amd_certs = psp_copy_user_blob(params.amd_certs_uaddr, 1199 params.amd_certs_len); 1200 if (IS_ERR(amd_certs)) { 1201 ret = PTR_ERR(amd_certs); 1202 goto e_free_plat_cert; 1203 } 1204 1205 /* populate the FW SEND_START field with system physical address */ 1206 memset(&data, 0, sizeof(data)); 1207 data.pdh_cert_address = __psp_pa(pdh_cert); 1208 data.pdh_cert_len = params.pdh_cert_len; 1209 data.plat_certs_address = __psp_pa(plat_certs); 1210 data.plat_certs_len = params.plat_certs_len; 1211 data.amd_certs_address = __psp_pa(amd_certs); 1212 data.amd_certs_len = params.amd_certs_len; 1213 data.session_address = __psp_pa(session_data); 1214 data.session_len = params.session_len; 1215 data.handle = sev->handle; 1216 1217 ret = sev_issue_cmd(kvm, SEV_CMD_SEND_START, &data, &argp->error); 1218 1219 if (!ret && copy_to_user((void __user *)(uintptr_t)params.session_uaddr, 1220 session_data, params.session_len)) { 1221 ret = -EFAULT; 1222 goto e_free_amd_cert; 1223 } 1224 1225 params.policy = data.policy; 1226 params.session_len = data.session_len; 1227 if (copy_to_user((void __user *)(uintptr_t)argp->data, ¶ms, 1228 sizeof(struct kvm_sev_send_start))) 1229 ret = -EFAULT; 1230 1231 e_free_amd_cert: 1232 kfree(amd_certs); 1233 e_free_plat_cert: 1234 kfree(plat_certs); 1235 e_free_pdh: 1236 kfree(pdh_cert); 1237 e_free_session: 1238 kfree(session_data); 1239 return ret; 1240 } 1241 1242 /* Userspace wants to query either header or trans length. */ 1243 static int 1244 __sev_send_update_data_query_lengths(struct kvm *kvm, struct kvm_sev_cmd *argp, 1245 struct kvm_sev_send_update_data *params) 1246 { 1247 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 1248 struct sev_data_send_update_data data; 1249 int ret; 1250 1251 memset(&data, 0, sizeof(data)); 1252 data.handle = sev->handle; 1253 ret = sev_issue_cmd(kvm, SEV_CMD_SEND_UPDATE_DATA, &data, &argp->error); 1254 1255 params->hdr_len = data.hdr_len; 1256 params->trans_len = data.trans_len; 1257 1258 if (copy_to_user((void __user *)(uintptr_t)argp->data, params, 1259 sizeof(struct kvm_sev_send_update_data))) 1260 ret = -EFAULT; 1261 1262 return ret; 1263 } 1264 1265 static int sev_send_update_data(struct kvm *kvm, struct kvm_sev_cmd *argp) 1266 { 1267 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 1268 struct sev_data_send_update_data data; 1269 struct kvm_sev_send_update_data params; 1270 void *hdr, *trans_data; 1271 struct page **guest_page; 1272 unsigned long n; 1273 int ret, offset; 1274 1275 if (!sev_guest(kvm)) 1276 return -ENOTTY; 1277 1278 if (copy_from_user(¶ms, (void __user *)(uintptr_t)argp->data, 1279 sizeof(struct kvm_sev_send_update_data))) 1280 return -EFAULT; 1281 1282 /* userspace wants to query either header or trans length */ 1283 if (!params.trans_len || !params.hdr_len) 1284 return __sev_send_update_data_query_lengths(kvm, argp, ¶ms); 1285 1286 if (!params.trans_uaddr || !params.guest_uaddr || 1287 !params.guest_len || !params.hdr_uaddr) 1288 return -EINVAL; 1289 1290 /* Check if we are crossing the page boundary */ 1291 offset = params.guest_uaddr & (PAGE_SIZE - 1); 1292 if ((params.guest_len + offset > PAGE_SIZE)) 1293 return -EINVAL; 1294 1295 /* Pin guest memory */ 1296 guest_page = sev_pin_memory(kvm, params.guest_uaddr & PAGE_MASK, 1297 PAGE_SIZE, &n, 0); 1298 if (IS_ERR(guest_page)) 1299 return PTR_ERR(guest_page); 1300 1301 /* allocate memory for header and transport buffer */ 1302 ret = -ENOMEM; 1303 hdr = kmalloc(params.hdr_len, GFP_KERNEL_ACCOUNT); 1304 if (!hdr) 1305 goto e_unpin; 1306 1307 trans_data = kmalloc(params.trans_len, GFP_KERNEL_ACCOUNT); 1308 if (!trans_data) 1309 goto e_free_hdr; 1310 1311 memset(&data, 0, sizeof(data)); 1312 data.hdr_address = __psp_pa(hdr); 1313 data.hdr_len = params.hdr_len; 1314 data.trans_address = __psp_pa(trans_data); 1315 data.trans_len = params.trans_len; 1316 1317 /* The SEND_UPDATE_DATA command requires C-bit to be always set. */ 1318 data.guest_address = (page_to_pfn(guest_page[0]) << PAGE_SHIFT) + offset; 1319 data.guest_address |= sev_me_mask; 1320 data.guest_len = params.guest_len; 1321 data.handle = sev->handle; 1322 1323 ret = sev_issue_cmd(kvm, SEV_CMD_SEND_UPDATE_DATA, &data, &argp->error); 1324 1325 if (ret) 1326 goto e_free_trans_data; 1327 1328 /* copy transport buffer to user space */ 1329 if (copy_to_user((void __user *)(uintptr_t)params.trans_uaddr, 1330 trans_data, params.trans_len)) { 1331 ret = -EFAULT; 1332 goto e_free_trans_data; 1333 } 1334 1335 /* Copy packet header to userspace. */ 1336 if (copy_to_user((void __user *)(uintptr_t)params.hdr_uaddr, hdr, 1337 params.hdr_len)) 1338 ret = -EFAULT; 1339 1340 e_free_trans_data: 1341 kfree(trans_data); 1342 e_free_hdr: 1343 kfree(hdr); 1344 e_unpin: 1345 sev_unpin_memory(kvm, guest_page, n); 1346 1347 return ret; 1348 } 1349 1350 static int sev_send_finish(struct kvm *kvm, struct kvm_sev_cmd *argp) 1351 { 1352 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 1353 struct sev_data_send_finish data; 1354 1355 if (!sev_guest(kvm)) 1356 return -ENOTTY; 1357 1358 data.handle = sev->handle; 1359 return sev_issue_cmd(kvm, SEV_CMD_SEND_FINISH, &data, &argp->error); 1360 } 1361 1362 static int sev_send_cancel(struct kvm *kvm, struct kvm_sev_cmd *argp) 1363 { 1364 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 1365 struct sev_data_send_cancel data; 1366 1367 if (!sev_guest(kvm)) 1368 return -ENOTTY; 1369 1370 data.handle = sev->handle; 1371 return sev_issue_cmd(kvm, SEV_CMD_SEND_CANCEL, &data, &argp->error); 1372 } 1373 1374 static int sev_receive_start(struct kvm *kvm, struct kvm_sev_cmd *argp) 1375 { 1376 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 1377 struct sev_data_receive_start start; 1378 struct kvm_sev_receive_start params; 1379 int *error = &argp->error; 1380 void *session_data; 1381 void *pdh_data; 1382 int ret; 1383 1384 if (!sev_guest(kvm)) 1385 return -ENOTTY; 1386 1387 /* Get parameter from the userspace */ 1388 if (copy_from_user(¶ms, (void __user *)(uintptr_t)argp->data, 1389 sizeof(struct kvm_sev_receive_start))) 1390 return -EFAULT; 1391 1392 /* some sanity checks */ 1393 if (!params.pdh_uaddr || !params.pdh_len || 1394 !params.session_uaddr || !params.session_len) 1395 return -EINVAL; 1396 1397 pdh_data = psp_copy_user_blob(params.pdh_uaddr, params.pdh_len); 1398 if (IS_ERR(pdh_data)) 1399 return PTR_ERR(pdh_data); 1400 1401 session_data = psp_copy_user_blob(params.session_uaddr, 1402 params.session_len); 1403 if (IS_ERR(session_data)) { 1404 ret = PTR_ERR(session_data); 1405 goto e_free_pdh; 1406 } 1407 1408 memset(&start, 0, sizeof(start)); 1409 start.handle = params.handle; 1410 start.policy = params.policy; 1411 start.pdh_cert_address = __psp_pa(pdh_data); 1412 start.pdh_cert_len = params.pdh_len; 1413 start.session_address = __psp_pa(session_data); 1414 start.session_len = params.session_len; 1415 1416 /* create memory encryption context */ 1417 ret = __sev_issue_cmd(argp->sev_fd, SEV_CMD_RECEIVE_START, &start, 1418 error); 1419 if (ret) 1420 goto e_free_session; 1421 1422 /* Bind ASID to this guest */ 1423 ret = sev_bind_asid(kvm, start.handle, error); 1424 if (ret) { 1425 sev_decommission(start.handle); 1426 goto e_free_session; 1427 } 1428 1429 params.handle = start.handle; 1430 if (copy_to_user((void __user *)(uintptr_t)argp->data, 1431 ¶ms, sizeof(struct kvm_sev_receive_start))) { 1432 ret = -EFAULT; 1433 sev_unbind_asid(kvm, start.handle); 1434 goto e_free_session; 1435 } 1436 1437 sev->handle = start.handle; 1438 sev->fd = argp->sev_fd; 1439 1440 e_free_session: 1441 kfree(session_data); 1442 e_free_pdh: 1443 kfree(pdh_data); 1444 1445 return ret; 1446 } 1447 1448 static int sev_receive_update_data(struct kvm *kvm, struct kvm_sev_cmd *argp) 1449 { 1450 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 1451 struct kvm_sev_receive_update_data params; 1452 struct sev_data_receive_update_data data; 1453 void *hdr = NULL, *trans = NULL; 1454 struct page **guest_page; 1455 unsigned long n; 1456 int ret, offset; 1457 1458 if (!sev_guest(kvm)) 1459 return -EINVAL; 1460 1461 if (copy_from_user(¶ms, (void __user *)(uintptr_t)argp->data, 1462 sizeof(struct kvm_sev_receive_update_data))) 1463 return -EFAULT; 1464 1465 if (!params.hdr_uaddr || !params.hdr_len || 1466 !params.guest_uaddr || !params.guest_len || 1467 !params.trans_uaddr || !params.trans_len) 1468 return -EINVAL; 1469 1470 /* Check if we are crossing the page boundary */ 1471 offset = params.guest_uaddr & (PAGE_SIZE - 1); 1472 if ((params.guest_len + offset > PAGE_SIZE)) 1473 return -EINVAL; 1474 1475 hdr = psp_copy_user_blob(params.hdr_uaddr, params.hdr_len); 1476 if (IS_ERR(hdr)) 1477 return PTR_ERR(hdr); 1478 1479 trans = psp_copy_user_blob(params.trans_uaddr, params.trans_len); 1480 if (IS_ERR(trans)) { 1481 ret = PTR_ERR(trans); 1482 goto e_free_hdr; 1483 } 1484 1485 memset(&data, 0, sizeof(data)); 1486 data.hdr_address = __psp_pa(hdr); 1487 data.hdr_len = params.hdr_len; 1488 data.trans_address = __psp_pa(trans); 1489 data.trans_len = params.trans_len; 1490 1491 /* Pin guest memory */ 1492 guest_page = sev_pin_memory(kvm, params.guest_uaddr & PAGE_MASK, 1493 PAGE_SIZE, &n, 1); 1494 if (IS_ERR(guest_page)) { 1495 ret = PTR_ERR(guest_page); 1496 goto e_free_trans; 1497 } 1498 1499 /* 1500 * Flush (on non-coherent CPUs) before RECEIVE_UPDATE_DATA, the PSP 1501 * encrypts the written data with the guest's key, and the cache may 1502 * contain dirty, unencrypted data. 1503 */ 1504 sev_clflush_pages(guest_page, n); 1505 1506 /* The RECEIVE_UPDATE_DATA command requires C-bit to be always set. */ 1507 data.guest_address = (page_to_pfn(guest_page[0]) << PAGE_SHIFT) + offset; 1508 data.guest_address |= sev_me_mask; 1509 data.guest_len = params.guest_len; 1510 data.handle = sev->handle; 1511 1512 ret = sev_issue_cmd(kvm, SEV_CMD_RECEIVE_UPDATE_DATA, &data, 1513 &argp->error); 1514 1515 sev_unpin_memory(kvm, guest_page, n); 1516 1517 e_free_trans: 1518 kfree(trans); 1519 e_free_hdr: 1520 kfree(hdr); 1521 1522 return ret; 1523 } 1524 1525 static int sev_receive_finish(struct kvm *kvm, struct kvm_sev_cmd *argp) 1526 { 1527 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 1528 struct sev_data_receive_finish data; 1529 1530 if (!sev_guest(kvm)) 1531 return -ENOTTY; 1532 1533 data.handle = sev->handle; 1534 return sev_issue_cmd(kvm, SEV_CMD_RECEIVE_FINISH, &data, &argp->error); 1535 } 1536 1537 static bool is_cmd_allowed_from_mirror(u32 cmd_id) 1538 { 1539 /* 1540 * Allow mirrors VM to call KVM_SEV_LAUNCH_UPDATE_VMSA to enable SEV-ES 1541 * active mirror VMs. Also allow the debugging and status commands. 1542 */ 1543 if (cmd_id == KVM_SEV_LAUNCH_UPDATE_VMSA || 1544 cmd_id == KVM_SEV_GUEST_STATUS || cmd_id == KVM_SEV_DBG_DECRYPT || 1545 cmd_id == KVM_SEV_DBG_ENCRYPT) 1546 return true; 1547 1548 return false; 1549 } 1550 1551 static int sev_lock_two_vms(struct kvm *dst_kvm, struct kvm *src_kvm) 1552 { 1553 struct kvm_sev_info *dst_sev = &to_kvm_svm(dst_kvm)->sev_info; 1554 struct kvm_sev_info *src_sev = &to_kvm_svm(src_kvm)->sev_info; 1555 int r = -EBUSY; 1556 1557 if (dst_kvm == src_kvm) 1558 return -EINVAL; 1559 1560 /* 1561 * Bail if these VMs are already involved in a migration to avoid 1562 * deadlock between two VMs trying to migrate to/from each other. 1563 */ 1564 if (atomic_cmpxchg_acquire(&dst_sev->migration_in_progress, 0, 1)) 1565 return -EBUSY; 1566 1567 if (atomic_cmpxchg_acquire(&src_sev->migration_in_progress, 0, 1)) 1568 goto release_dst; 1569 1570 r = -EINTR; 1571 if (mutex_lock_killable(&dst_kvm->lock)) 1572 goto release_src; 1573 if (mutex_lock_killable_nested(&src_kvm->lock, SINGLE_DEPTH_NESTING)) 1574 goto unlock_dst; 1575 return 0; 1576 1577 unlock_dst: 1578 mutex_unlock(&dst_kvm->lock); 1579 release_src: 1580 atomic_set_release(&src_sev->migration_in_progress, 0); 1581 release_dst: 1582 atomic_set_release(&dst_sev->migration_in_progress, 0); 1583 return r; 1584 } 1585 1586 static void sev_unlock_two_vms(struct kvm *dst_kvm, struct kvm *src_kvm) 1587 { 1588 struct kvm_sev_info *dst_sev = &to_kvm_svm(dst_kvm)->sev_info; 1589 struct kvm_sev_info *src_sev = &to_kvm_svm(src_kvm)->sev_info; 1590 1591 mutex_unlock(&dst_kvm->lock); 1592 mutex_unlock(&src_kvm->lock); 1593 atomic_set_release(&dst_sev->migration_in_progress, 0); 1594 atomic_set_release(&src_sev->migration_in_progress, 0); 1595 } 1596 1597 /* vCPU mutex subclasses. */ 1598 enum sev_migration_role { 1599 SEV_MIGRATION_SOURCE = 0, 1600 SEV_MIGRATION_TARGET, 1601 SEV_NR_MIGRATION_ROLES, 1602 }; 1603 1604 static int sev_lock_vcpus_for_migration(struct kvm *kvm, 1605 enum sev_migration_role role) 1606 { 1607 struct kvm_vcpu *vcpu; 1608 unsigned long i, j; 1609 bool first = true; 1610 1611 kvm_for_each_vcpu(i, vcpu, kvm) { 1612 if (mutex_lock_killable_nested(&vcpu->mutex, role)) 1613 goto out_unlock; 1614 1615 if (first) { 1616 /* 1617 * Reset the role to one that avoids colliding with 1618 * the role used for the first vcpu mutex. 1619 */ 1620 role = SEV_NR_MIGRATION_ROLES; 1621 first = false; 1622 } else { 1623 mutex_release(&vcpu->mutex.dep_map, _THIS_IP_); 1624 } 1625 } 1626 1627 return 0; 1628 1629 out_unlock: 1630 1631 first = true; 1632 kvm_for_each_vcpu(j, vcpu, kvm) { 1633 if (i == j) 1634 break; 1635 1636 if (first) 1637 first = false; 1638 else 1639 mutex_acquire(&vcpu->mutex.dep_map, role, 0, _THIS_IP_); 1640 1641 1642 mutex_unlock(&vcpu->mutex); 1643 } 1644 return -EINTR; 1645 } 1646 1647 static void sev_unlock_vcpus_for_migration(struct kvm *kvm) 1648 { 1649 struct kvm_vcpu *vcpu; 1650 unsigned long i; 1651 bool first = true; 1652 1653 kvm_for_each_vcpu(i, vcpu, kvm) { 1654 if (first) 1655 first = false; 1656 else 1657 mutex_acquire(&vcpu->mutex.dep_map, 1658 SEV_NR_MIGRATION_ROLES, 0, _THIS_IP_); 1659 1660 mutex_unlock(&vcpu->mutex); 1661 } 1662 } 1663 1664 static void sev_migrate_from(struct kvm *dst_kvm, struct kvm *src_kvm) 1665 { 1666 struct kvm_sev_info *dst = &to_kvm_svm(dst_kvm)->sev_info; 1667 struct kvm_sev_info *src = &to_kvm_svm(src_kvm)->sev_info; 1668 struct kvm_sev_info *mirror; 1669 1670 dst->active = true; 1671 dst->asid = src->asid; 1672 dst->handle = src->handle; 1673 dst->pages_locked = src->pages_locked; 1674 dst->enc_context_owner = src->enc_context_owner; 1675 1676 src->asid = 0; 1677 src->active = false; 1678 src->handle = 0; 1679 src->pages_locked = 0; 1680 src->enc_context_owner = NULL; 1681 1682 list_cut_before(&dst->regions_list, &src->regions_list, &src->regions_list); 1683 1684 /* 1685 * If this VM has mirrors, "transfer" each mirror's refcount of the 1686 * source to the destination (this KVM). The caller holds a reference 1687 * to the source, so there's no danger of use-after-free. 1688 */ 1689 list_cut_before(&dst->mirror_vms, &src->mirror_vms, &src->mirror_vms); 1690 list_for_each_entry(mirror, &dst->mirror_vms, mirror_entry) { 1691 kvm_get_kvm(dst_kvm); 1692 kvm_put_kvm(src_kvm); 1693 mirror->enc_context_owner = dst_kvm; 1694 } 1695 1696 /* 1697 * If this VM is a mirror, remove the old mirror from the owners list 1698 * and add the new mirror to the list. 1699 */ 1700 if (is_mirroring_enc_context(dst_kvm)) { 1701 struct kvm_sev_info *owner_sev_info = 1702 &to_kvm_svm(dst->enc_context_owner)->sev_info; 1703 1704 list_del(&src->mirror_entry); 1705 list_add_tail(&dst->mirror_entry, &owner_sev_info->mirror_vms); 1706 } 1707 } 1708 1709 static int sev_es_migrate_from(struct kvm *dst, struct kvm *src) 1710 { 1711 unsigned long i; 1712 struct kvm_vcpu *dst_vcpu, *src_vcpu; 1713 struct vcpu_svm *dst_svm, *src_svm; 1714 1715 if (atomic_read(&src->online_vcpus) != atomic_read(&dst->online_vcpus)) 1716 return -EINVAL; 1717 1718 kvm_for_each_vcpu(i, src_vcpu, src) { 1719 if (!src_vcpu->arch.guest_state_protected) 1720 return -EINVAL; 1721 } 1722 1723 kvm_for_each_vcpu(i, src_vcpu, src) { 1724 src_svm = to_svm(src_vcpu); 1725 dst_vcpu = kvm_get_vcpu(dst, i); 1726 dst_svm = to_svm(dst_vcpu); 1727 1728 /* 1729 * Transfer VMSA and GHCB state to the destination. Nullify and 1730 * clear source fields as appropriate, the state now belongs to 1731 * the destination. 1732 */ 1733 memcpy(&dst_svm->sev_es, &src_svm->sev_es, sizeof(src_svm->sev_es)); 1734 dst_svm->vmcb->control.ghcb_gpa = src_svm->vmcb->control.ghcb_gpa; 1735 dst_svm->vmcb->control.vmsa_pa = src_svm->vmcb->control.vmsa_pa; 1736 dst_vcpu->arch.guest_state_protected = true; 1737 1738 memset(&src_svm->sev_es, 0, sizeof(src_svm->sev_es)); 1739 src_svm->vmcb->control.ghcb_gpa = INVALID_PAGE; 1740 src_svm->vmcb->control.vmsa_pa = INVALID_PAGE; 1741 src_vcpu->arch.guest_state_protected = false; 1742 } 1743 to_kvm_svm(src)->sev_info.es_active = false; 1744 to_kvm_svm(dst)->sev_info.es_active = true; 1745 1746 return 0; 1747 } 1748 1749 int sev_vm_move_enc_context_from(struct kvm *kvm, unsigned int source_fd) 1750 { 1751 struct kvm_sev_info *dst_sev = &to_kvm_svm(kvm)->sev_info; 1752 struct kvm_sev_info *src_sev, *cg_cleanup_sev; 1753 struct file *source_kvm_file; 1754 struct kvm *source_kvm; 1755 bool charged = false; 1756 int ret; 1757 1758 source_kvm_file = fget(source_fd); 1759 if (!file_is_kvm(source_kvm_file)) { 1760 ret = -EBADF; 1761 goto out_fput; 1762 } 1763 1764 source_kvm = source_kvm_file->private_data; 1765 ret = sev_lock_two_vms(kvm, source_kvm); 1766 if (ret) 1767 goto out_fput; 1768 1769 if (sev_guest(kvm) || !sev_guest(source_kvm)) { 1770 ret = -EINVAL; 1771 goto out_unlock; 1772 } 1773 1774 src_sev = &to_kvm_svm(source_kvm)->sev_info; 1775 1776 dst_sev->misc_cg = get_current_misc_cg(); 1777 cg_cleanup_sev = dst_sev; 1778 if (dst_sev->misc_cg != src_sev->misc_cg) { 1779 ret = sev_misc_cg_try_charge(dst_sev); 1780 if (ret) 1781 goto out_dst_cgroup; 1782 charged = true; 1783 } 1784 1785 ret = sev_lock_vcpus_for_migration(kvm, SEV_MIGRATION_SOURCE); 1786 if (ret) 1787 goto out_dst_cgroup; 1788 ret = sev_lock_vcpus_for_migration(source_kvm, SEV_MIGRATION_TARGET); 1789 if (ret) 1790 goto out_dst_vcpu; 1791 1792 if (sev_es_guest(source_kvm)) { 1793 ret = sev_es_migrate_from(kvm, source_kvm); 1794 if (ret) 1795 goto out_source_vcpu; 1796 } 1797 1798 sev_migrate_from(kvm, source_kvm); 1799 kvm_vm_dead(source_kvm); 1800 cg_cleanup_sev = src_sev; 1801 ret = 0; 1802 1803 out_source_vcpu: 1804 sev_unlock_vcpus_for_migration(source_kvm); 1805 out_dst_vcpu: 1806 sev_unlock_vcpus_for_migration(kvm); 1807 out_dst_cgroup: 1808 /* Operates on the source on success, on the destination on failure. */ 1809 if (charged) 1810 sev_misc_cg_uncharge(cg_cleanup_sev); 1811 put_misc_cg(cg_cleanup_sev->misc_cg); 1812 cg_cleanup_sev->misc_cg = NULL; 1813 out_unlock: 1814 sev_unlock_two_vms(kvm, source_kvm); 1815 out_fput: 1816 if (source_kvm_file) 1817 fput(source_kvm_file); 1818 return ret; 1819 } 1820 1821 int sev_mem_enc_ioctl(struct kvm *kvm, void __user *argp) 1822 { 1823 struct kvm_sev_cmd sev_cmd; 1824 int r; 1825 1826 if (!sev_enabled) 1827 return -ENOTTY; 1828 1829 if (!argp) 1830 return 0; 1831 1832 if (copy_from_user(&sev_cmd, argp, sizeof(struct kvm_sev_cmd))) 1833 return -EFAULT; 1834 1835 mutex_lock(&kvm->lock); 1836 1837 /* Only the enc_context_owner handles some memory enc operations. */ 1838 if (is_mirroring_enc_context(kvm) && 1839 !is_cmd_allowed_from_mirror(sev_cmd.id)) { 1840 r = -EINVAL; 1841 goto out; 1842 } 1843 1844 switch (sev_cmd.id) { 1845 case KVM_SEV_ES_INIT: 1846 if (!sev_es_enabled) { 1847 r = -ENOTTY; 1848 goto out; 1849 } 1850 fallthrough; 1851 case KVM_SEV_INIT: 1852 r = sev_guest_init(kvm, &sev_cmd); 1853 break; 1854 case KVM_SEV_LAUNCH_START: 1855 r = sev_launch_start(kvm, &sev_cmd); 1856 break; 1857 case KVM_SEV_LAUNCH_UPDATE_DATA: 1858 r = sev_launch_update_data(kvm, &sev_cmd); 1859 break; 1860 case KVM_SEV_LAUNCH_UPDATE_VMSA: 1861 r = sev_launch_update_vmsa(kvm, &sev_cmd); 1862 break; 1863 case KVM_SEV_LAUNCH_MEASURE: 1864 r = sev_launch_measure(kvm, &sev_cmd); 1865 break; 1866 case KVM_SEV_LAUNCH_FINISH: 1867 r = sev_launch_finish(kvm, &sev_cmd); 1868 break; 1869 case KVM_SEV_GUEST_STATUS: 1870 r = sev_guest_status(kvm, &sev_cmd); 1871 break; 1872 case KVM_SEV_DBG_DECRYPT: 1873 r = sev_dbg_crypt(kvm, &sev_cmd, true); 1874 break; 1875 case KVM_SEV_DBG_ENCRYPT: 1876 r = sev_dbg_crypt(kvm, &sev_cmd, false); 1877 break; 1878 case KVM_SEV_LAUNCH_SECRET: 1879 r = sev_launch_secret(kvm, &sev_cmd); 1880 break; 1881 case KVM_SEV_GET_ATTESTATION_REPORT: 1882 r = sev_get_attestation_report(kvm, &sev_cmd); 1883 break; 1884 case KVM_SEV_SEND_START: 1885 r = sev_send_start(kvm, &sev_cmd); 1886 break; 1887 case KVM_SEV_SEND_UPDATE_DATA: 1888 r = sev_send_update_data(kvm, &sev_cmd); 1889 break; 1890 case KVM_SEV_SEND_FINISH: 1891 r = sev_send_finish(kvm, &sev_cmd); 1892 break; 1893 case KVM_SEV_SEND_CANCEL: 1894 r = sev_send_cancel(kvm, &sev_cmd); 1895 break; 1896 case KVM_SEV_RECEIVE_START: 1897 r = sev_receive_start(kvm, &sev_cmd); 1898 break; 1899 case KVM_SEV_RECEIVE_UPDATE_DATA: 1900 r = sev_receive_update_data(kvm, &sev_cmd); 1901 break; 1902 case KVM_SEV_RECEIVE_FINISH: 1903 r = sev_receive_finish(kvm, &sev_cmd); 1904 break; 1905 default: 1906 r = -EINVAL; 1907 goto out; 1908 } 1909 1910 if (copy_to_user(argp, &sev_cmd, sizeof(struct kvm_sev_cmd))) 1911 r = -EFAULT; 1912 1913 out: 1914 mutex_unlock(&kvm->lock); 1915 return r; 1916 } 1917 1918 int sev_mem_enc_register_region(struct kvm *kvm, 1919 struct kvm_enc_region *range) 1920 { 1921 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 1922 struct enc_region *region; 1923 int ret = 0; 1924 1925 if (!sev_guest(kvm)) 1926 return -ENOTTY; 1927 1928 /* If kvm is mirroring encryption context it isn't responsible for it */ 1929 if (is_mirroring_enc_context(kvm)) 1930 return -EINVAL; 1931 1932 if (range->addr > ULONG_MAX || range->size > ULONG_MAX) 1933 return -EINVAL; 1934 1935 region = kzalloc(sizeof(*region), GFP_KERNEL_ACCOUNT); 1936 if (!region) 1937 return -ENOMEM; 1938 1939 mutex_lock(&kvm->lock); 1940 region->pages = sev_pin_memory(kvm, range->addr, range->size, ®ion->npages, 1); 1941 if (IS_ERR(region->pages)) { 1942 ret = PTR_ERR(region->pages); 1943 mutex_unlock(&kvm->lock); 1944 goto e_free; 1945 } 1946 1947 region->uaddr = range->addr; 1948 region->size = range->size; 1949 1950 list_add_tail(®ion->list, &sev->regions_list); 1951 mutex_unlock(&kvm->lock); 1952 1953 /* 1954 * The guest may change the memory encryption attribute from C=0 -> C=1 1955 * or vice versa for this memory range. Lets make sure caches are 1956 * flushed to ensure that guest data gets written into memory with 1957 * correct C-bit. 1958 */ 1959 sev_clflush_pages(region->pages, region->npages); 1960 1961 return ret; 1962 1963 e_free: 1964 kfree(region); 1965 return ret; 1966 } 1967 1968 static struct enc_region * 1969 find_enc_region(struct kvm *kvm, struct kvm_enc_region *range) 1970 { 1971 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 1972 struct list_head *head = &sev->regions_list; 1973 struct enc_region *i; 1974 1975 list_for_each_entry(i, head, list) { 1976 if (i->uaddr == range->addr && 1977 i->size == range->size) 1978 return i; 1979 } 1980 1981 return NULL; 1982 } 1983 1984 static void __unregister_enc_region_locked(struct kvm *kvm, 1985 struct enc_region *region) 1986 { 1987 sev_unpin_memory(kvm, region->pages, region->npages); 1988 list_del(®ion->list); 1989 kfree(region); 1990 } 1991 1992 int sev_mem_enc_unregister_region(struct kvm *kvm, 1993 struct kvm_enc_region *range) 1994 { 1995 struct enc_region *region; 1996 int ret; 1997 1998 /* If kvm is mirroring encryption context it isn't responsible for it */ 1999 if (is_mirroring_enc_context(kvm)) 2000 return -EINVAL; 2001 2002 mutex_lock(&kvm->lock); 2003 2004 if (!sev_guest(kvm)) { 2005 ret = -ENOTTY; 2006 goto failed; 2007 } 2008 2009 region = find_enc_region(kvm, range); 2010 if (!region) { 2011 ret = -EINVAL; 2012 goto failed; 2013 } 2014 2015 /* 2016 * Ensure that all guest tagged cache entries are flushed before 2017 * releasing the pages back to the system for use. CLFLUSH will 2018 * not do this, so issue a WBINVD. 2019 */ 2020 wbinvd_on_all_cpus(); 2021 2022 __unregister_enc_region_locked(kvm, region); 2023 2024 mutex_unlock(&kvm->lock); 2025 return 0; 2026 2027 failed: 2028 mutex_unlock(&kvm->lock); 2029 return ret; 2030 } 2031 2032 int sev_vm_copy_enc_context_from(struct kvm *kvm, unsigned int source_fd) 2033 { 2034 struct file *source_kvm_file; 2035 struct kvm *source_kvm; 2036 struct kvm_sev_info *source_sev, *mirror_sev; 2037 int ret; 2038 2039 source_kvm_file = fget(source_fd); 2040 if (!file_is_kvm(source_kvm_file)) { 2041 ret = -EBADF; 2042 goto e_source_fput; 2043 } 2044 2045 source_kvm = source_kvm_file->private_data; 2046 ret = sev_lock_two_vms(kvm, source_kvm); 2047 if (ret) 2048 goto e_source_fput; 2049 2050 /* 2051 * Mirrors of mirrors should work, but let's not get silly. Also 2052 * disallow out-of-band SEV/SEV-ES init if the target is already an 2053 * SEV guest, or if vCPUs have been created. KVM relies on vCPUs being 2054 * created after SEV/SEV-ES initialization, e.g. to init intercepts. 2055 */ 2056 if (sev_guest(kvm) || !sev_guest(source_kvm) || 2057 is_mirroring_enc_context(source_kvm) || kvm->created_vcpus) { 2058 ret = -EINVAL; 2059 goto e_unlock; 2060 } 2061 2062 /* 2063 * The mirror kvm holds an enc_context_owner ref so its asid can't 2064 * disappear until we're done with it 2065 */ 2066 source_sev = &to_kvm_svm(source_kvm)->sev_info; 2067 kvm_get_kvm(source_kvm); 2068 mirror_sev = &to_kvm_svm(kvm)->sev_info; 2069 list_add_tail(&mirror_sev->mirror_entry, &source_sev->mirror_vms); 2070 2071 /* Set enc_context_owner and copy its encryption context over */ 2072 mirror_sev->enc_context_owner = source_kvm; 2073 mirror_sev->active = true; 2074 mirror_sev->asid = source_sev->asid; 2075 mirror_sev->fd = source_sev->fd; 2076 mirror_sev->es_active = source_sev->es_active; 2077 mirror_sev->handle = source_sev->handle; 2078 INIT_LIST_HEAD(&mirror_sev->regions_list); 2079 INIT_LIST_HEAD(&mirror_sev->mirror_vms); 2080 ret = 0; 2081 2082 /* 2083 * Do not copy ap_jump_table. Since the mirror does not share the same 2084 * KVM contexts as the original, and they may have different 2085 * memory-views. 2086 */ 2087 2088 e_unlock: 2089 sev_unlock_two_vms(kvm, source_kvm); 2090 e_source_fput: 2091 if (source_kvm_file) 2092 fput(source_kvm_file); 2093 return ret; 2094 } 2095 2096 void sev_vm_destroy(struct kvm *kvm) 2097 { 2098 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 2099 struct list_head *head = &sev->regions_list; 2100 struct list_head *pos, *q; 2101 2102 if (!sev_guest(kvm)) 2103 return; 2104 2105 WARN_ON(!list_empty(&sev->mirror_vms)); 2106 2107 /* If this is a mirror_kvm release the enc_context_owner and skip sev cleanup */ 2108 if (is_mirroring_enc_context(kvm)) { 2109 struct kvm *owner_kvm = sev->enc_context_owner; 2110 2111 mutex_lock(&owner_kvm->lock); 2112 list_del(&sev->mirror_entry); 2113 mutex_unlock(&owner_kvm->lock); 2114 kvm_put_kvm(owner_kvm); 2115 return; 2116 } 2117 2118 /* 2119 * Ensure that all guest tagged cache entries are flushed before 2120 * releasing the pages back to the system for use. CLFLUSH will 2121 * not do this, so issue a WBINVD. 2122 */ 2123 wbinvd_on_all_cpus(); 2124 2125 /* 2126 * if userspace was terminated before unregistering the memory regions 2127 * then lets unpin all the registered memory. 2128 */ 2129 if (!list_empty(head)) { 2130 list_for_each_safe(pos, q, head) { 2131 __unregister_enc_region_locked(kvm, 2132 list_entry(pos, struct enc_region, list)); 2133 cond_resched(); 2134 } 2135 } 2136 2137 sev_unbind_asid(kvm, sev->handle); 2138 sev_asid_free(sev); 2139 } 2140 2141 void __init sev_set_cpu_caps(void) 2142 { 2143 if (!sev_enabled) 2144 kvm_cpu_cap_clear(X86_FEATURE_SEV); 2145 if (!sev_es_enabled) 2146 kvm_cpu_cap_clear(X86_FEATURE_SEV_ES); 2147 } 2148 2149 void __init sev_hardware_setup(void) 2150 { 2151 #ifdef CONFIG_KVM_AMD_SEV 2152 unsigned int eax, ebx, ecx, edx, sev_asid_count, sev_es_asid_count; 2153 bool sev_es_supported = false; 2154 bool sev_supported = false; 2155 2156 if (!sev_enabled || !npt_enabled) 2157 goto out; 2158 2159 /* 2160 * SEV must obviously be supported in hardware. Sanity check that the 2161 * CPU supports decode assists, which is mandatory for SEV guests to 2162 * support instruction emulation. 2163 */ 2164 if (!boot_cpu_has(X86_FEATURE_SEV) || 2165 WARN_ON_ONCE(!boot_cpu_has(X86_FEATURE_DECODEASSISTS))) 2166 goto out; 2167 2168 /* Retrieve SEV CPUID information */ 2169 cpuid(0x8000001f, &eax, &ebx, &ecx, &edx); 2170 2171 /* Set encryption bit location for SEV-ES guests */ 2172 sev_enc_bit = ebx & 0x3f; 2173 2174 /* Maximum number of encrypted guests supported simultaneously */ 2175 max_sev_asid = ecx; 2176 if (!max_sev_asid) 2177 goto out; 2178 2179 /* Minimum ASID value that should be used for SEV guest */ 2180 min_sev_asid = edx; 2181 sev_me_mask = 1UL << (ebx & 0x3f); 2182 2183 /* 2184 * Initialize SEV ASID bitmaps. Allocate space for ASID 0 in the bitmap, 2185 * even though it's never used, so that the bitmap is indexed by the 2186 * actual ASID. 2187 */ 2188 nr_asids = max_sev_asid + 1; 2189 sev_asid_bitmap = bitmap_zalloc(nr_asids, GFP_KERNEL); 2190 if (!sev_asid_bitmap) 2191 goto out; 2192 2193 sev_reclaim_asid_bitmap = bitmap_zalloc(nr_asids, GFP_KERNEL); 2194 if (!sev_reclaim_asid_bitmap) { 2195 bitmap_free(sev_asid_bitmap); 2196 sev_asid_bitmap = NULL; 2197 goto out; 2198 } 2199 2200 sev_asid_count = max_sev_asid - min_sev_asid + 1; 2201 if (misc_cg_set_capacity(MISC_CG_RES_SEV, sev_asid_count)) 2202 goto out; 2203 2204 pr_info("SEV supported: %u ASIDs\n", sev_asid_count); 2205 sev_supported = true; 2206 2207 /* SEV-ES support requested? */ 2208 if (!sev_es_enabled) 2209 goto out; 2210 2211 /* Does the CPU support SEV-ES? */ 2212 if (!boot_cpu_has(X86_FEATURE_SEV_ES)) 2213 goto out; 2214 2215 /* Has the system been allocated ASIDs for SEV-ES? */ 2216 if (min_sev_asid == 1) 2217 goto out; 2218 2219 sev_es_asid_count = min_sev_asid - 1; 2220 if (misc_cg_set_capacity(MISC_CG_RES_SEV_ES, sev_es_asid_count)) 2221 goto out; 2222 2223 pr_info("SEV-ES supported: %u ASIDs\n", sev_es_asid_count); 2224 sev_es_supported = true; 2225 2226 out: 2227 sev_enabled = sev_supported; 2228 sev_es_enabled = sev_es_supported; 2229 #endif 2230 } 2231 2232 void sev_hardware_unsetup(void) 2233 { 2234 if (!sev_enabled) 2235 return; 2236 2237 /* No need to take sev_bitmap_lock, all VMs have been destroyed. */ 2238 sev_flush_asids(1, max_sev_asid); 2239 2240 bitmap_free(sev_asid_bitmap); 2241 bitmap_free(sev_reclaim_asid_bitmap); 2242 2243 misc_cg_set_capacity(MISC_CG_RES_SEV, 0); 2244 misc_cg_set_capacity(MISC_CG_RES_SEV_ES, 0); 2245 } 2246 2247 int sev_cpu_init(struct svm_cpu_data *sd) 2248 { 2249 if (!sev_enabled) 2250 return 0; 2251 2252 sd->sev_vmcbs = kcalloc(nr_asids, sizeof(void *), GFP_KERNEL); 2253 if (!sd->sev_vmcbs) 2254 return -ENOMEM; 2255 2256 return 0; 2257 } 2258 2259 /* 2260 * Pages used by hardware to hold guest encrypted state must be flushed before 2261 * returning them to the system. 2262 */ 2263 static void sev_flush_encrypted_page(struct kvm_vcpu *vcpu, void *va) 2264 { 2265 int asid = to_kvm_svm(vcpu->kvm)->sev_info.asid; 2266 2267 /* 2268 * Note! The address must be a kernel address, as regular page walk 2269 * checks are performed by VM_PAGE_FLUSH, i.e. operating on a user 2270 * address is non-deterministic and unsafe. This function deliberately 2271 * takes a pointer to deter passing in a user address. 2272 */ 2273 unsigned long addr = (unsigned long)va; 2274 2275 /* 2276 * If CPU enforced cache coherency for encrypted mappings of the 2277 * same physical page is supported, use CLFLUSHOPT instead. NOTE: cache 2278 * flush is still needed in order to work properly with DMA devices. 2279 */ 2280 if (boot_cpu_has(X86_FEATURE_SME_COHERENT)) { 2281 clflush_cache_range(va, PAGE_SIZE); 2282 return; 2283 } 2284 2285 /* 2286 * VM Page Flush takes a host virtual address and a guest ASID. Fall 2287 * back to WBINVD if this faults so as not to make any problems worse 2288 * by leaving stale encrypted data in the cache. 2289 */ 2290 if (WARN_ON_ONCE(wrmsrl_safe(MSR_AMD64_VM_PAGE_FLUSH, addr | asid))) 2291 goto do_wbinvd; 2292 2293 return; 2294 2295 do_wbinvd: 2296 wbinvd_on_all_cpus(); 2297 } 2298 2299 void sev_guest_memory_reclaimed(struct kvm *kvm) 2300 { 2301 if (!sev_guest(kvm)) 2302 return; 2303 2304 wbinvd_on_all_cpus(); 2305 } 2306 2307 void sev_free_vcpu(struct kvm_vcpu *vcpu) 2308 { 2309 struct vcpu_svm *svm; 2310 2311 if (!sev_es_guest(vcpu->kvm)) 2312 return; 2313 2314 svm = to_svm(vcpu); 2315 2316 if (vcpu->arch.guest_state_protected) 2317 sev_flush_encrypted_page(vcpu, svm->sev_es.vmsa); 2318 2319 __free_page(virt_to_page(svm->sev_es.vmsa)); 2320 2321 if (svm->sev_es.ghcb_sa_free) 2322 kvfree(svm->sev_es.ghcb_sa); 2323 } 2324 2325 static void dump_ghcb(struct vcpu_svm *svm) 2326 { 2327 struct ghcb *ghcb = svm->sev_es.ghcb; 2328 unsigned int nbits; 2329 2330 /* Re-use the dump_invalid_vmcb module parameter */ 2331 if (!dump_invalid_vmcb) { 2332 pr_warn_ratelimited("set kvm_amd.dump_invalid_vmcb=1 to dump internal KVM state.\n"); 2333 return; 2334 } 2335 2336 nbits = sizeof(ghcb->save.valid_bitmap) * 8; 2337 2338 pr_err("GHCB (GPA=%016llx):\n", svm->vmcb->control.ghcb_gpa); 2339 pr_err("%-20s%016llx is_valid: %u\n", "sw_exit_code", 2340 ghcb->save.sw_exit_code, ghcb_sw_exit_code_is_valid(ghcb)); 2341 pr_err("%-20s%016llx is_valid: %u\n", "sw_exit_info_1", 2342 ghcb->save.sw_exit_info_1, ghcb_sw_exit_info_1_is_valid(ghcb)); 2343 pr_err("%-20s%016llx is_valid: %u\n", "sw_exit_info_2", 2344 ghcb->save.sw_exit_info_2, ghcb_sw_exit_info_2_is_valid(ghcb)); 2345 pr_err("%-20s%016llx is_valid: %u\n", "sw_scratch", 2346 ghcb->save.sw_scratch, ghcb_sw_scratch_is_valid(ghcb)); 2347 pr_err("%-20s%*pb\n", "valid_bitmap", nbits, ghcb->save.valid_bitmap); 2348 } 2349 2350 static void sev_es_sync_to_ghcb(struct vcpu_svm *svm) 2351 { 2352 struct kvm_vcpu *vcpu = &svm->vcpu; 2353 struct ghcb *ghcb = svm->sev_es.ghcb; 2354 2355 /* 2356 * The GHCB protocol so far allows for the following data 2357 * to be returned: 2358 * GPRs RAX, RBX, RCX, RDX 2359 * 2360 * Copy their values, even if they may not have been written during the 2361 * VM-Exit. It's the guest's responsibility to not consume random data. 2362 */ 2363 ghcb_set_rax(ghcb, vcpu->arch.regs[VCPU_REGS_RAX]); 2364 ghcb_set_rbx(ghcb, vcpu->arch.regs[VCPU_REGS_RBX]); 2365 ghcb_set_rcx(ghcb, vcpu->arch.regs[VCPU_REGS_RCX]); 2366 ghcb_set_rdx(ghcb, vcpu->arch.regs[VCPU_REGS_RDX]); 2367 } 2368 2369 static void sev_es_sync_from_ghcb(struct vcpu_svm *svm) 2370 { 2371 struct vmcb_control_area *control = &svm->vmcb->control; 2372 struct kvm_vcpu *vcpu = &svm->vcpu; 2373 struct ghcb *ghcb = svm->sev_es.ghcb; 2374 u64 exit_code; 2375 2376 /* 2377 * The GHCB protocol so far allows for the following data 2378 * to be supplied: 2379 * GPRs RAX, RBX, RCX, RDX 2380 * XCR0 2381 * CPL 2382 * 2383 * VMMCALL allows the guest to provide extra registers. KVM also 2384 * expects RSI for hypercalls, so include that, too. 2385 * 2386 * Copy their values to the appropriate location if supplied. 2387 */ 2388 memset(vcpu->arch.regs, 0, sizeof(vcpu->arch.regs)); 2389 2390 vcpu->arch.regs[VCPU_REGS_RAX] = ghcb_get_rax_if_valid(ghcb); 2391 vcpu->arch.regs[VCPU_REGS_RBX] = ghcb_get_rbx_if_valid(ghcb); 2392 vcpu->arch.regs[VCPU_REGS_RCX] = ghcb_get_rcx_if_valid(ghcb); 2393 vcpu->arch.regs[VCPU_REGS_RDX] = ghcb_get_rdx_if_valid(ghcb); 2394 vcpu->arch.regs[VCPU_REGS_RSI] = ghcb_get_rsi_if_valid(ghcb); 2395 2396 svm->vmcb->save.cpl = ghcb_get_cpl_if_valid(ghcb); 2397 2398 if (ghcb_xcr0_is_valid(ghcb)) { 2399 vcpu->arch.xcr0 = ghcb_get_xcr0(ghcb); 2400 kvm_update_cpuid_runtime(vcpu); 2401 } 2402 2403 /* Copy the GHCB exit information into the VMCB fields */ 2404 exit_code = ghcb_get_sw_exit_code(ghcb); 2405 control->exit_code = lower_32_bits(exit_code); 2406 control->exit_code_hi = upper_32_bits(exit_code); 2407 control->exit_info_1 = ghcb_get_sw_exit_info_1(ghcb); 2408 control->exit_info_2 = ghcb_get_sw_exit_info_2(ghcb); 2409 2410 /* Clear the valid entries fields */ 2411 memset(ghcb->save.valid_bitmap, 0, sizeof(ghcb->save.valid_bitmap)); 2412 } 2413 2414 static int sev_es_validate_vmgexit(struct vcpu_svm *svm) 2415 { 2416 struct kvm_vcpu *vcpu; 2417 struct ghcb *ghcb; 2418 u64 exit_code; 2419 u64 reason; 2420 2421 ghcb = svm->sev_es.ghcb; 2422 2423 /* 2424 * Retrieve the exit code now even though it may not be marked valid 2425 * as it could help with debugging. 2426 */ 2427 exit_code = ghcb_get_sw_exit_code(ghcb); 2428 2429 /* Only GHCB Usage code 0 is supported */ 2430 if (ghcb->ghcb_usage) { 2431 reason = GHCB_ERR_INVALID_USAGE; 2432 goto vmgexit_err; 2433 } 2434 2435 reason = GHCB_ERR_MISSING_INPUT; 2436 2437 if (!ghcb_sw_exit_code_is_valid(ghcb) || 2438 !ghcb_sw_exit_info_1_is_valid(ghcb) || 2439 !ghcb_sw_exit_info_2_is_valid(ghcb)) 2440 goto vmgexit_err; 2441 2442 switch (ghcb_get_sw_exit_code(ghcb)) { 2443 case SVM_EXIT_READ_DR7: 2444 break; 2445 case SVM_EXIT_WRITE_DR7: 2446 if (!ghcb_rax_is_valid(ghcb)) 2447 goto vmgexit_err; 2448 break; 2449 case SVM_EXIT_RDTSC: 2450 break; 2451 case SVM_EXIT_RDPMC: 2452 if (!ghcb_rcx_is_valid(ghcb)) 2453 goto vmgexit_err; 2454 break; 2455 case SVM_EXIT_CPUID: 2456 if (!ghcb_rax_is_valid(ghcb) || 2457 !ghcb_rcx_is_valid(ghcb)) 2458 goto vmgexit_err; 2459 if (ghcb_get_rax(ghcb) == 0xd) 2460 if (!ghcb_xcr0_is_valid(ghcb)) 2461 goto vmgexit_err; 2462 break; 2463 case SVM_EXIT_INVD: 2464 break; 2465 case SVM_EXIT_IOIO: 2466 if (ghcb_get_sw_exit_info_1(ghcb) & SVM_IOIO_STR_MASK) { 2467 if (!ghcb_sw_scratch_is_valid(ghcb)) 2468 goto vmgexit_err; 2469 } else { 2470 if (!(ghcb_get_sw_exit_info_1(ghcb) & SVM_IOIO_TYPE_MASK)) 2471 if (!ghcb_rax_is_valid(ghcb)) 2472 goto vmgexit_err; 2473 } 2474 break; 2475 case SVM_EXIT_MSR: 2476 if (!ghcb_rcx_is_valid(ghcb)) 2477 goto vmgexit_err; 2478 if (ghcb_get_sw_exit_info_1(ghcb)) { 2479 if (!ghcb_rax_is_valid(ghcb) || 2480 !ghcb_rdx_is_valid(ghcb)) 2481 goto vmgexit_err; 2482 } 2483 break; 2484 case SVM_EXIT_VMMCALL: 2485 if (!ghcb_rax_is_valid(ghcb) || 2486 !ghcb_cpl_is_valid(ghcb)) 2487 goto vmgexit_err; 2488 break; 2489 case SVM_EXIT_RDTSCP: 2490 break; 2491 case SVM_EXIT_WBINVD: 2492 break; 2493 case SVM_EXIT_MONITOR: 2494 if (!ghcb_rax_is_valid(ghcb) || 2495 !ghcb_rcx_is_valid(ghcb) || 2496 !ghcb_rdx_is_valid(ghcb)) 2497 goto vmgexit_err; 2498 break; 2499 case SVM_EXIT_MWAIT: 2500 if (!ghcb_rax_is_valid(ghcb) || 2501 !ghcb_rcx_is_valid(ghcb)) 2502 goto vmgexit_err; 2503 break; 2504 case SVM_VMGEXIT_MMIO_READ: 2505 case SVM_VMGEXIT_MMIO_WRITE: 2506 if (!ghcb_sw_scratch_is_valid(ghcb)) 2507 goto vmgexit_err; 2508 break; 2509 case SVM_VMGEXIT_NMI_COMPLETE: 2510 case SVM_VMGEXIT_AP_HLT_LOOP: 2511 case SVM_VMGEXIT_AP_JUMP_TABLE: 2512 case SVM_VMGEXIT_UNSUPPORTED_EVENT: 2513 break; 2514 default: 2515 reason = GHCB_ERR_INVALID_EVENT; 2516 goto vmgexit_err; 2517 } 2518 2519 return 0; 2520 2521 vmgexit_err: 2522 vcpu = &svm->vcpu; 2523 2524 if (reason == GHCB_ERR_INVALID_USAGE) { 2525 vcpu_unimpl(vcpu, "vmgexit: ghcb usage %#x is not valid\n", 2526 ghcb->ghcb_usage); 2527 } else if (reason == GHCB_ERR_INVALID_EVENT) { 2528 vcpu_unimpl(vcpu, "vmgexit: exit code %#llx is not valid\n", 2529 exit_code); 2530 } else { 2531 vcpu_unimpl(vcpu, "vmgexit: exit code %#llx input is not valid\n", 2532 exit_code); 2533 dump_ghcb(svm); 2534 } 2535 2536 /* Clear the valid entries fields */ 2537 memset(ghcb->save.valid_bitmap, 0, sizeof(ghcb->save.valid_bitmap)); 2538 2539 ghcb_set_sw_exit_info_1(ghcb, 2); 2540 ghcb_set_sw_exit_info_2(ghcb, reason); 2541 2542 /* Resume the guest to "return" the error code. */ 2543 return 1; 2544 } 2545 2546 void sev_es_unmap_ghcb(struct vcpu_svm *svm) 2547 { 2548 if (!svm->sev_es.ghcb) 2549 return; 2550 2551 if (svm->sev_es.ghcb_sa_free) { 2552 /* 2553 * The scratch area lives outside the GHCB, so there is a 2554 * buffer that, depending on the operation performed, may 2555 * need to be synced, then freed. 2556 */ 2557 if (svm->sev_es.ghcb_sa_sync) { 2558 kvm_write_guest(svm->vcpu.kvm, 2559 ghcb_get_sw_scratch(svm->sev_es.ghcb), 2560 svm->sev_es.ghcb_sa, 2561 svm->sev_es.ghcb_sa_len); 2562 svm->sev_es.ghcb_sa_sync = false; 2563 } 2564 2565 kvfree(svm->sev_es.ghcb_sa); 2566 svm->sev_es.ghcb_sa = NULL; 2567 svm->sev_es.ghcb_sa_free = false; 2568 } 2569 2570 trace_kvm_vmgexit_exit(svm->vcpu.vcpu_id, svm->sev_es.ghcb); 2571 2572 sev_es_sync_to_ghcb(svm); 2573 2574 kvm_vcpu_unmap(&svm->vcpu, &svm->sev_es.ghcb_map, true); 2575 svm->sev_es.ghcb = NULL; 2576 } 2577 2578 void pre_sev_run(struct vcpu_svm *svm, int cpu) 2579 { 2580 struct svm_cpu_data *sd = per_cpu(svm_data, cpu); 2581 int asid = sev_get_asid(svm->vcpu.kvm); 2582 2583 /* Assign the asid allocated with this SEV guest */ 2584 svm->asid = asid; 2585 2586 /* 2587 * Flush guest TLB: 2588 * 2589 * 1) when different VMCB for the same ASID is to be run on the same host CPU. 2590 * 2) or this VMCB was executed on different host CPU in previous VMRUNs. 2591 */ 2592 if (sd->sev_vmcbs[asid] == svm->vmcb && 2593 svm->vcpu.arch.last_vmentry_cpu == cpu) 2594 return; 2595 2596 sd->sev_vmcbs[asid] = svm->vmcb; 2597 svm->vmcb->control.tlb_ctl = TLB_CONTROL_FLUSH_ASID; 2598 vmcb_mark_dirty(svm->vmcb, VMCB_ASID); 2599 } 2600 2601 #define GHCB_SCRATCH_AREA_LIMIT (16ULL * PAGE_SIZE) 2602 static int setup_vmgexit_scratch(struct vcpu_svm *svm, bool sync, u64 len) 2603 { 2604 struct vmcb_control_area *control = &svm->vmcb->control; 2605 struct ghcb *ghcb = svm->sev_es.ghcb; 2606 u64 ghcb_scratch_beg, ghcb_scratch_end; 2607 u64 scratch_gpa_beg, scratch_gpa_end; 2608 void *scratch_va; 2609 2610 scratch_gpa_beg = ghcb_get_sw_scratch(ghcb); 2611 if (!scratch_gpa_beg) { 2612 pr_err("vmgexit: scratch gpa not provided\n"); 2613 goto e_scratch; 2614 } 2615 2616 scratch_gpa_end = scratch_gpa_beg + len; 2617 if (scratch_gpa_end < scratch_gpa_beg) { 2618 pr_err("vmgexit: scratch length (%#llx) not valid for scratch address (%#llx)\n", 2619 len, scratch_gpa_beg); 2620 goto e_scratch; 2621 } 2622 2623 if ((scratch_gpa_beg & PAGE_MASK) == control->ghcb_gpa) { 2624 /* Scratch area begins within GHCB */ 2625 ghcb_scratch_beg = control->ghcb_gpa + 2626 offsetof(struct ghcb, shared_buffer); 2627 ghcb_scratch_end = control->ghcb_gpa + 2628 offsetof(struct ghcb, reserved_1); 2629 2630 /* 2631 * If the scratch area begins within the GHCB, it must be 2632 * completely contained in the GHCB shared buffer area. 2633 */ 2634 if (scratch_gpa_beg < ghcb_scratch_beg || 2635 scratch_gpa_end > ghcb_scratch_end) { 2636 pr_err("vmgexit: scratch area is outside of GHCB shared buffer area (%#llx - %#llx)\n", 2637 scratch_gpa_beg, scratch_gpa_end); 2638 goto e_scratch; 2639 } 2640 2641 scratch_va = (void *)svm->sev_es.ghcb; 2642 scratch_va += (scratch_gpa_beg - control->ghcb_gpa); 2643 } else { 2644 /* 2645 * The guest memory must be read into a kernel buffer, so 2646 * limit the size 2647 */ 2648 if (len > GHCB_SCRATCH_AREA_LIMIT) { 2649 pr_err("vmgexit: scratch area exceeds KVM limits (%#llx requested, %#llx limit)\n", 2650 len, GHCB_SCRATCH_AREA_LIMIT); 2651 goto e_scratch; 2652 } 2653 scratch_va = kvzalloc(len, GFP_KERNEL_ACCOUNT); 2654 if (!scratch_va) 2655 return -ENOMEM; 2656 2657 if (kvm_read_guest(svm->vcpu.kvm, scratch_gpa_beg, scratch_va, len)) { 2658 /* Unable to copy scratch area from guest */ 2659 pr_err("vmgexit: kvm_read_guest for scratch area failed\n"); 2660 2661 kvfree(scratch_va); 2662 return -EFAULT; 2663 } 2664 2665 /* 2666 * The scratch area is outside the GHCB. The operation will 2667 * dictate whether the buffer needs to be synced before running 2668 * the vCPU next time (i.e. a read was requested so the data 2669 * must be written back to the guest memory). 2670 */ 2671 svm->sev_es.ghcb_sa_sync = sync; 2672 svm->sev_es.ghcb_sa_free = true; 2673 } 2674 2675 svm->sev_es.ghcb_sa = scratch_va; 2676 svm->sev_es.ghcb_sa_len = len; 2677 2678 return 0; 2679 2680 e_scratch: 2681 ghcb_set_sw_exit_info_1(ghcb, 2); 2682 ghcb_set_sw_exit_info_2(ghcb, GHCB_ERR_INVALID_SCRATCH_AREA); 2683 2684 return 1; 2685 } 2686 2687 static void set_ghcb_msr_bits(struct vcpu_svm *svm, u64 value, u64 mask, 2688 unsigned int pos) 2689 { 2690 svm->vmcb->control.ghcb_gpa &= ~(mask << pos); 2691 svm->vmcb->control.ghcb_gpa |= (value & mask) << pos; 2692 } 2693 2694 static u64 get_ghcb_msr_bits(struct vcpu_svm *svm, u64 mask, unsigned int pos) 2695 { 2696 return (svm->vmcb->control.ghcb_gpa >> pos) & mask; 2697 } 2698 2699 static void set_ghcb_msr(struct vcpu_svm *svm, u64 value) 2700 { 2701 svm->vmcb->control.ghcb_gpa = value; 2702 } 2703 2704 static int sev_handle_vmgexit_msr_protocol(struct vcpu_svm *svm) 2705 { 2706 struct vmcb_control_area *control = &svm->vmcb->control; 2707 struct kvm_vcpu *vcpu = &svm->vcpu; 2708 u64 ghcb_info; 2709 int ret = 1; 2710 2711 ghcb_info = control->ghcb_gpa & GHCB_MSR_INFO_MASK; 2712 2713 trace_kvm_vmgexit_msr_protocol_enter(svm->vcpu.vcpu_id, 2714 control->ghcb_gpa); 2715 2716 switch (ghcb_info) { 2717 case GHCB_MSR_SEV_INFO_REQ: 2718 set_ghcb_msr(svm, GHCB_MSR_SEV_INFO(GHCB_VERSION_MAX, 2719 GHCB_VERSION_MIN, 2720 sev_enc_bit)); 2721 break; 2722 case GHCB_MSR_CPUID_REQ: { 2723 u64 cpuid_fn, cpuid_reg, cpuid_value; 2724 2725 cpuid_fn = get_ghcb_msr_bits(svm, 2726 GHCB_MSR_CPUID_FUNC_MASK, 2727 GHCB_MSR_CPUID_FUNC_POS); 2728 2729 /* Initialize the registers needed by the CPUID intercept */ 2730 vcpu->arch.regs[VCPU_REGS_RAX] = cpuid_fn; 2731 vcpu->arch.regs[VCPU_REGS_RCX] = 0; 2732 2733 ret = svm_invoke_exit_handler(vcpu, SVM_EXIT_CPUID); 2734 if (!ret) { 2735 /* Error, keep GHCB MSR value as-is */ 2736 break; 2737 } 2738 2739 cpuid_reg = get_ghcb_msr_bits(svm, 2740 GHCB_MSR_CPUID_REG_MASK, 2741 GHCB_MSR_CPUID_REG_POS); 2742 if (cpuid_reg == 0) 2743 cpuid_value = vcpu->arch.regs[VCPU_REGS_RAX]; 2744 else if (cpuid_reg == 1) 2745 cpuid_value = vcpu->arch.regs[VCPU_REGS_RBX]; 2746 else if (cpuid_reg == 2) 2747 cpuid_value = vcpu->arch.regs[VCPU_REGS_RCX]; 2748 else 2749 cpuid_value = vcpu->arch.regs[VCPU_REGS_RDX]; 2750 2751 set_ghcb_msr_bits(svm, cpuid_value, 2752 GHCB_MSR_CPUID_VALUE_MASK, 2753 GHCB_MSR_CPUID_VALUE_POS); 2754 2755 set_ghcb_msr_bits(svm, GHCB_MSR_CPUID_RESP, 2756 GHCB_MSR_INFO_MASK, 2757 GHCB_MSR_INFO_POS); 2758 break; 2759 } 2760 case GHCB_MSR_TERM_REQ: { 2761 u64 reason_set, reason_code; 2762 2763 reason_set = get_ghcb_msr_bits(svm, 2764 GHCB_MSR_TERM_REASON_SET_MASK, 2765 GHCB_MSR_TERM_REASON_SET_POS); 2766 reason_code = get_ghcb_msr_bits(svm, 2767 GHCB_MSR_TERM_REASON_MASK, 2768 GHCB_MSR_TERM_REASON_POS); 2769 pr_info("SEV-ES guest requested termination: %#llx:%#llx\n", 2770 reason_set, reason_code); 2771 2772 ret = -EINVAL; 2773 break; 2774 } 2775 default: 2776 /* Error, keep GHCB MSR value as-is */ 2777 break; 2778 } 2779 2780 trace_kvm_vmgexit_msr_protocol_exit(svm->vcpu.vcpu_id, 2781 control->ghcb_gpa, ret); 2782 2783 return ret; 2784 } 2785 2786 int sev_handle_vmgexit(struct kvm_vcpu *vcpu) 2787 { 2788 struct vcpu_svm *svm = to_svm(vcpu); 2789 struct vmcb_control_area *control = &svm->vmcb->control; 2790 u64 ghcb_gpa, exit_code; 2791 struct ghcb *ghcb; 2792 int ret; 2793 2794 /* Validate the GHCB */ 2795 ghcb_gpa = control->ghcb_gpa; 2796 if (ghcb_gpa & GHCB_MSR_INFO_MASK) 2797 return sev_handle_vmgexit_msr_protocol(svm); 2798 2799 if (!ghcb_gpa) { 2800 vcpu_unimpl(vcpu, "vmgexit: GHCB gpa is not set\n"); 2801 2802 /* Without a GHCB, just return right back to the guest */ 2803 return 1; 2804 } 2805 2806 if (kvm_vcpu_map(vcpu, ghcb_gpa >> PAGE_SHIFT, &svm->sev_es.ghcb_map)) { 2807 /* Unable to map GHCB from guest */ 2808 vcpu_unimpl(vcpu, "vmgexit: error mapping GHCB [%#llx] from guest\n", 2809 ghcb_gpa); 2810 2811 /* Without a GHCB, just return right back to the guest */ 2812 return 1; 2813 } 2814 2815 svm->sev_es.ghcb = svm->sev_es.ghcb_map.hva; 2816 ghcb = svm->sev_es.ghcb_map.hva; 2817 2818 trace_kvm_vmgexit_enter(vcpu->vcpu_id, ghcb); 2819 2820 exit_code = ghcb_get_sw_exit_code(ghcb); 2821 2822 ret = sev_es_validate_vmgexit(svm); 2823 if (ret) 2824 return ret; 2825 2826 sev_es_sync_from_ghcb(svm); 2827 ghcb_set_sw_exit_info_1(ghcb, 0); 2828 ghcb_set_sw_exit_info_2(ghcb, 0); 2829 2830 switch (exit_code) { 2831 case SVM_VMGEXIT_MMIO_READ: 2832 ret = setup_vmgexit_scratch(svm, true, control->exit_info_2); 2833 if (ret) 2834 break; 2835 2836 ret = kvm_sev_es_mmio_read(vcpu, 2837 control->exit_info_1, 2838 control->exit_info_2, 2839 svm->sev_es.ghcb_sa); 2840 break; 2841 case SVM_VMGEXIT_MMIO_WRITE: 2842 ret = setup_vmgexit_scratch(svm, false, control->exit_info_2); 2843 if (ret) 2844 break; 2845 2846 ret = kvm_sev_es_mmio_write(vcpu, 2847 control->exit_info_1, 2848 control->exit_info_2, 2849 svm->sev_es.ghcb_sa); 2850 break; 2851 case SVM_VMGEXIT_NMI_COMPLETE: 2852 ret = svm_invoke_exit_handler(vcpu, SVM_EXIT_IRET); 2853 break; 2854 case SVM_VMGEXIT_AP_HLT_LOOP: 2855 ret = kvm_emulate_ap_reset_hold(vcpu); 2856 break; 2857 case SVM_VMGEXIT_AP_JUMP_TABLE: { 2858 struct kvm_sev_info *sev = &to_kvm_svm(vcpu->kvm)->sev_info; 2859 2860 switch (control->exit_info_1) { 2861 case 0: 2862 /* Set AP jump table address */ 2863 sev->ap_jump_table = control->exit_info_2; 2864 break; 2865 case 1: 2866 /* Get AP jump table address */ 2867 ghcb_set_sw_exit_info_2(ghcb, sev->ap_jump_table); 2868 break; 2869 default: 2870 pr_err("svm: vmgexit: unsupported AP jump table request - exit_info_1=%#llx\n", 2871 control->exit_info_1); 2872 ghcb_set_sw_exit_info_1(ghcb, 2); 2873 ghcb_set_sw_exit_info_2(ghcb, GHCB_ERR_INVALID_INPUT); 2874 } 2875 2876 ret = 1; 2877 break; 2878 } 2879 case SVM_VMGEXIT_UNSUPPORTED_EVENT: 2880 vcpu_unimpl(vcpu, 2881 "vmgexit: unsupported event - exit_info_1=%#llx, exit_info_2=%#llx\n", 2882 control->exit_info_1, control->exit_info_2); 2883 ret = -EINVAL; 2884 break; 2885 default: 2886 ret = svm_invoke_exit_handler(vcpu, exit_code); 2887 } 2888 2889 return ret; 2890 } 2891 2892 int sev_es_string_io(struct vcpu_svm *svm, int size, unsigned int port, int in) 2893 { 2894 int count; 2895 int bytes; 2896 int r; 2897 2898 if (svm->vmcb->control.exit_info_2 > INT_MAX) 2899 return -EINVAL; 2900 2901 count = svm->vmcb->control.exit_info_2; 2902 if (unlikely(check_mul_overflow(count, size, &bytes))) 2903 return -EINVAL; 2904 2905 r = setup_vmgexit_scratch(svm, in, bytes); 2906 if (r) 2907 return r; 2908 2909 return kvm_sev_es_string_io(&svm->vcpu, size, port, svm->sev_es.ghcb_sa, 2910 count, in); 2911 } 2912 2913 void sev_es_init_vmcb(struct vcpu_svm *svm) 2914 { 2915 struct kvm_vcpu *vcpu = &svm->vcpu; 2916 2917 svm->vmcb->control.nested_ctl |= SVM_NESTED_CTL_SEV_ES_ENABLE; 2918 svm->vmcb->control.virt_ext |= LBR_CTL_ENABLE_MASK; 2919 2920 /* 2921 * An SEV-ES guest requires a VMSA area that is a separate from the 2922 * VMCB page. Do not include the encryption mask on the VMSA physical 2923 * address since hardware will access it using the guest key. 2924 */ 2925 svm->vmcb->control.vmsa_pa = __pa(svm->sev_es.vmsa); 2926 2927 /* Can't intercept CR register access, HV can't modify CR registers */ 2928 svm_clr_intercept(svm, INTERCEPT_CR0_READ); 2929 svm_clr_intercept(svm, INTERCEPT_CR4_READ); 2930 svm_clr_intercept(svm, INTERCEPT_CR8_READ); 2931 svm_clr_intercept(svm, INTERCEPT_CR0_WRITE); 2932 svm_clr_intercept(svm, INTERCEPT_CR4_WRITE); 2933 svm_clr_intercept(svm, INTERCEPT_CR8_WRITE); 2934 2935 svm_clr_intercept(svm, INTERCEPT_SELECTIVE_CR0); 2936 2937 /* Track EFER/CR register changes */ 2938 svm_set_intercept(svm, TRAP_EFER_WRITE); 2939 svm_set_intercept(svm, TRAP_CR0_WRITE); 2940 svm_set_intercept(svm, TRAP_CR4_WRITE); 2941 svm_set_intercept(svm, TRAP_CR8_WRITE); 2942 2943 /* No support for enable_vmware_backdoor */ 2944 clr_exception_intercept(svm, GP_VECTOR); 2945 2946 /* Can't intercept XSETBV, HV can't modify XCR0 directly */ 2947 svm_clr_intercept(svm, INTERCEPT_XSETBV); 2948 2949 /* Clear intercepts on selected MSRs */ 2950 set_msr_interception(vcpu, svm->msrpm, MSR_EFER, 1, 1); 2951 set_msr_interception(vcpu, svm->msrpm, MSR_IA32_CR_PAT, 1, 1); 2952 set_msr_interception(vcpu, svm->msrpm, MSR_IA32_LASTBRANCHFROMIP, 1, 1); 2953 set_msr_interception(vcpu, svm->msrpm, MSR_IA32_LASTBRANCHTOIP, 1, 1); 2954 set_msr_interception(vcpu, svm->msrpm, MSR_IA32_LASTINTFROMIP, 1, 1); 2955 set_msr_interception(vcpu, svm->msrpm, MSR_IA32_LASTINTTOIP, 1, 1); 2956 } 2957 2958 void sev_es_vcpu_reset(struct vcpu_svm *svm) 2959 { 2960 /* 2961 * Set the GHCB MSR value as per the GHCB specification when emulating 2962 * vCPU RESET for an SEV-ES guest. 2963 */ 2964 set_ghcb_msr(svm, GHCB_MSR_SEV_INFO(GHCB_VERSION_MAX, 2965 GHCB_VERSION_MIN, 2966 sev_enc_bit)); 2967 } 2968 2969 void sev_es_prepare_switch_to_guest(struct vmcb_save_area *hostsa) 2970 { 2971 /* 2972 * As an SEV-ES guest, hardware will restore the host state on VMEXIT, 2973 * of which one step is to perform a VMLOAD. KVM performs the 2974 * corresponding VMSAVE in svm_prepare_guest_switch for both 2975 * traditional and SEV-ES guests. 2976 */ 2977 2978 /* XCR0 is restored on VMEXIT, save the current host value */ 2979 hostsa->xcr0 = xgetbv(XCR_XFEATURE_ENABLED_MASK); 2980 2981 /* PKRU is restored on VMEXIT, save the current host value */ 2982 hostsa->pkru = read_pkru(); 2983 2984 /* MSR_IA32_XSS is restored on VMEXIT, save the currnet host value */ 2985 hostsa->xss = host_xss; 2986 } 2987 2988 void sev_vcpu_deliver_sipi_vector(struct kvm_vcpu *vcpu, u8 vector) 2989 { 2990 struct vcpu_svm *svm = to_svm(vcpu); 2991 2992 /* First SIPI: Use the values as initially set by the VMM */ 2993 if (!svm->sev_es.received_first_sipi) { 2994 svm->sev_es.received_first_sipi = true; 2995 return; 2996 } 2997 2998 /* 2999 * Subsequent SIPI: Return from an AP Reset Hold VMGEXIT, where 3000 * the guest will set the CS and RIP. Set SW_EXIT_INFO_2 to a 3001 * non-zero value. 3002 */ 3003 if (!svm->sev_es.ghcb) 3004 return; 3005 3006 ghcb_set_sw_exit_info_2(svm->sev_es.ghcb, 1); 3007 } 3008