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 27 #include "mmu.h" 28 #include "x86.h" 29 #include "svm.h" 30 #include "svm_ops.h" 31 #include "cpuid.h" 32 #include "trace.h" 33 34 #ifndef CONFIG_KVM_AMD_SEV 35 /* 36 * When this config is not defined, SEV feature is not supported and APIs in 37 * this file are not used but this file still gets compiled into the KVM AMD 38 * module. 39 * 40 * We will not have MISC_CG_RES_SEV and MISC_CG_RES_SEV_ES entries in the enum 41 * misc_res_type {} defined in linux/misc_cgroup.h. 42 * 43 * Below macros allow compilation to succeed. 44 */ 45 #define MISC_CG_RES_SEV MISC_CG_RES_TYPES 46 #define MISC_CG_RES_SEV_ES MISC_CG_RES_TYPES 47 #endif 48 49 #ifdef CONFIG_KVM_AMD_SEV 50 /* enable/disable SEV support */ 51 static bool sev_enabled = true; 52 module_param_named(sev, sev_enabled, bool, 0444); 53 54 /* enable/disable SEV-ES support */ 55 static bool sev_es_enabled = true; 56 module_param_named(sev_es, sev_es_enabled, bool, 0444); 57 #else 58 #define sev_enabled false 59 #define sev_es_enabled false 60 #endif /* CONFIG_KVM_AMD_SEV */ 61 62 static u8 sev_enc_bit; 63 static DECLARE_RWSEM(sev_deactivate_lock); 64 static DEFINE_MUTEX(sev_bitmap_lock); 65 unsigned int max_sev_asid; 66 static unsigned int min_sev_asid; 67 static unsigned long sev_me_mask; 68 static unsigned int nr_asids; 69 static unsigned long *sev_asid_bitmap; 70 static unsigned long *sev_reclaim_asid_bitmap; 71 72 struct enc_region { 73 struct list_head list; 74 unsigned long npages; 75 struct page **pages; 76 unsigned long uaddr; 77 unsigned long size; 78 }; 79 80 /* Called with the sev_bitmap_lock held, or on shutdown */ 81 static int sev_flush_asids(int min_asid, int max_asid) 82 { 83 int ret, asid, error = 0; 84 85 /* Check if there are any ASIDs to reclaim before performing a flush */ 86 asid = find_next_bit(sev_reclaim_asid_bitmap, nr_asids, min_asid); 87 if (asid > max_asid) 88 return -EBUSY; 89 90 /* 91 * DEACTIVATE will clear the WBINVD indicator causing DF_FLUSH to fail, 92 * so it must be guarded. 93 */ 94 down_write(&sev_deactivate_lock); 95 96 wbinvd_on_all_cpus(); 97 ret = sev_guest_df_flush(&error); 98 99 up_write(&sev_deactivate_lock); 100 101 if (ret) 102 pr_err("SEV: DF_FLUSH failed, ret=%d, error=%#x\n", ret, error); 103 104 return ret; 105 } 106 107 static inline bool is_mirroring_enc_context(struct kvm *kvm) 108 { 109 return !!to_kvm_svm(kvm)->sev_info.enc_context_owner; 110 } 111 112 /* Must be called with the sev_bitmap_lock held */ 113 static bool __sev_recycle_asids(int min_asid, int max_asid) 114 { 115 if (sev_flush_asids(min_asid, max_asid)) 116 return false; 117 118 /* The flush process will flush all reclaimable SEV and SEV-ES ASIDs */ 119 bitmap_xor(sev_asid_bitmap, sev_asid_bitmap, sev_reclaim_asid_bitmap, 120 nr_asids); 121 bitmap_zero(sev_reclaim_asid_bitmap, nr_asids); 122 123 return true; 124 } 125 126 static int sev_misc_cg_try_charge(struct kvm_sev_info *sev) 127 { 128 enum misc_res_type type = sev->es_active ? MISC_CG_RES_SEV_ES : MISC_CG_RES_SEV; 129 return misc_cg_try_charge(type, sev->misc_cg, 1); 130 } 131 132 static void sev_misc_cg_uncharge(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 misc_cg_uncharge(type, sev->misc_cg, 1); 136 } 137 138 static int sev_asid_new(struct kvm_sev_info *sev) 139 { 140 int asid, min_asid, max_asid, ret; 141 bool retry = true; 142 143 WARN_ON(sev->misc_cg); 144 sev->misc_cg = get_current_misc_cg(); 145 ret = sev_misc_cg_try_charge(sev); 146 if (ret) { 147 put_misc_cg(sev->misc_cg); 148 sev->misc_cg = NULL; 149 return ret; 150 } 151 152 mutex_lock(&sev_bitmap_lock); 153 154 /* 155 * SEV-enabled guests must use asid from min_sev_asid to max_sev_asid. 156 * SEV-ES-enabled guest can use from 1 to min_sev_asid - 1. 157 */ 158 min_asid = sev->es_active ? 1 : min_sev_asid; 159 max_asid = sev->es_active ? min_sev_asid - 1 : max_sev_asid; 160 again: 161 asid = find_next_zero_bit(sev_asid_bitmap, max_asid + 1, min_asid); 162 if (asid > max_asid) { 163 if (retry && __sev_recycle_asids(min_asid, max_asid)) { 164 retry = false; 165 goto again; 166 } 167 mutex_unlock(&sev_bitmap_lock); 168 ret = -EBUSY; 169 goto e_uncharge; 170 } 171 172 __set_bit(asid, sev_asid_bitmap); 173 174 mutex_unlock(&sev_bitmap_lock); 175 176 return asid; 177 e_uncharge: 178 sev_misc_cg_uncharge(sev); 179 put_misc_cg(sev->misc_cg); 180 sev->misc_cg = NULL; 181 return ret; 182 } 183 184 static int sev_get_asid(struct kvm *kvm) 185 { 186 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 187 188 return sev->asid; 189 } 190 191 static void sev_asid_free(struct kvm_sev_info *sev) 192 { 193 struct svm_cpu_data *sd; 194 int cpu; 195 196 mutex_lock(&sev_bitmap_lock); 197 198 __set_bit(sev->asid, sev_reclaim_asid_bitmap); 199 200 for_each_possible_cpu(cpu) { 201 sd = per_cpu_ptr(&svm_data, cpu); 202 sd->sev_vmcbs[sev->asid] = NULL; 203 } 204 205 mutex_unlock(&sev_bitmap_lock); 206 207 sev_misc_cg_uncharge(sev); 208 put_misc_cg(sev->misc_cg); 209 sev->misc_cg = NULL; 210 } 211 212 static void sev_decommission(unsigned int handle) 213 { 214 struct sev_data_decommission decommission; 215 216 if (!handle) 217 return; 218 219 decommission.handle = handle; 220 sev_guest_decommission(&decommission, NULL); 221 } 222 223 static void sev_unbind_asid(struct kvm *kvm, unsigned int handle) 224 { 225 struct sev_data_deactivate deactivate; 226 227 if (!handle) 228 return; 229 230 deactivate.handle = handle; 231 232 /* Guard DEACTIVATE against WBINVD/DF_FLUSH used in ASID recycling */ 233 down_read(&sev_deactivate_lock); 234 sev_guest_deactivate(&deactivate, NULL); 235 up_read(&sev_deactivate_lock); 236 237 sev_decommission(handle); 238 } 239 240 static int sev_guest_init(struct kvm *kvm, struct kvm_sev_cmd *argp) 241 { 242 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 243 int asid, ret; 244 245 if (kvm->created_vcpus) 246 return -EINVAL; 247 248 ret = -EBUSY; 249 if (unlikely(sev->active)) 250 return ret; 251 252 sev->active = true; 253 sev->es_active = argp->id == KVM_SEV_ES_INIT; 254 asid = sev_asid_new(sev); 255 if (asid < 0) 256 goto e_no_asid; 257 sev->asid = asid; 258 259 ret = sev_platform_init(&argp->error); 260 if (ret) 261 goto e_free; 262 263 INIT_LIST_HEAD(&sev->regions_list); 264 INIT_LIST_HEAD(&sev->mirror_vms); 265 266 kvm_set_apicv_inhibit(kvm, APICV_INHIBIT_REASON_SEV); 267 268 return 0; 269 270 e_free: 271 sev_asid_free(sev); 272 sev->asid = 0; 273 e_no_asid: 274 sev->es_active = false; 275 sev->active = false; 276 return ret; 277 } 278 279 static int sev_bind_asid(struct kvm *kvm, unsigned int handle, int *error) 280 { 281 struct sev_data_activate activate; 282 int asid = sev_get_asid(kvm); 283 int ret; 284 285 /* activate ASID on the given handle */ 286 activate.handle = handle; 287 activate.asid = asid; 288 ret = sev_guest_activate(&activate, error); 289 290 return ret; 291 } 292 293 static int __sev_issue_cmd(int fd, int id, void *data, int *error) 294 { 295 struct fd f; 296 int ret; 297 298 f = fdget(fd); 299 if (!f.file) 300 return -EBADF; 301 302 ret = sev_issue_cmd_external_user(f.file, id, data, error); 303 304 fdput(f); 305 return ret; 306 } 307 308 static int sev_issue_cmd(struct kvm *kvm, int id, void *data, int *error) 309 { 310 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 311 312 return __sev_issue_cmd(sev->fd, id, data, error); 313 } 314 315 static int sev_launch_start(struct kvm *kvm, struct kvm_sev_cmd *argp) 316 { 317 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 318 struct sev_data_launch_start start; 319 struct kvm_sev_launch_start params; 320 void *dh_blob, *session_blob; 321 int *error = &argp->error; 322 int ret; 323 324 if (!sev_guest(kvm)) 325 return -ENOTTY; 326 327 if (copy_from_user(¶ms, (void __user *)(uintptr_t)argp->data, sizeof(params))) 328 return -EFAULT; 329 330 memset(&start, 0, sizeof(start)); 331 332 dh_blob = NULL; 333 if (params.dh_uaddr) { 334 dh_blob = psp_copy_user_blob(params.dh_uaddr, params.dh_len); 335 if (IS_ERR(dh_blob)) 336 return PTR_ERR(dh_blob); 337 338 start.dh_cert_address = __sme_set(__pa(dh_blob)); 339 start.dh_cert_len = params.dh_len; 340 } 341 342 session_blob = NULL; 343 if (params.session_uaddr) { 344 session_blob = psp_copy_user_blob(params.session_uaddr, params.session_len); 345 if (IS_ERR(session_blob)) { 346 ret = PTR_ERR(session_blob); 347 goto e_free_dh; 348 } 349 350 start.session_address = __sme_set(__pa(session_blob)); 351 start.session_len = params.session_len; 352 } 353 354 start.handle = params.handle; 355 start.policy = params.policy; 356 357 /* create memory encryption context */ 358 ret = __sev_issue_cmd(argp->sev_fd, SEV_CMD_LAUNCH_START, &start, error); 359 if (ret) 360 goto e_free_session; 361 362 /* Bind ASID to this guest */ 363 ret = sev_bind_asid(kvm, start.handle, error); 364 if (ret) { 365 sev_decommission(start.handle); 366 goto e_free_session; 367 } 368 369 /* return handle to userspace */ 370 params.handle = start.handle; 371 if (copy_to_user((void __user *)(uintptr_t)argp->data, ¶ms, sizeof(params))) { 372 sev_unbind_asid(kvm, start.handle); 373 ret = -EFAULT; 374 goto e_free_session; 375 } 376 377 sev->handle = start.handle; 378 sev->fd = argp->sev_fd; 379 380 e_free_session: 381 kfree(session_blob); 382 e_free_dh: 383 kfree(dh_blob); 384 return ret; 385 } 386 387 static struct page **sev_pin_memory(struct kvm *kvm, unsigned long uaddr, 388 unsigned long ulen, unsigned long *n, 389 int write) 390 { 391 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 392 unsigned long npages, size; 393 int npinned; 394 unsigned long locked, lock_limit; 395 struct page **pages; 396 unsigned long first, last; 397 int ret; 398 399 lockdep_assert_held(&kvm->lock); 400 401 if (ulen == 0 || uaddr + ulen < uaddr) 402 return ERR_PTR(-EINVAL); 403 404 /* Calculate number of pages. */ 405 first = (uaddr & PAGE_MASK) >> PAGE_SHIFT; 406 last = ((uaddr + ulen - 1) & PAGE_MASK) >> PAGE_SHIFT; 407 npages = (last - first + 1); 408 409 locked = sev->pages_locked + npages; 410 lock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT; 411 if (locked > lock_limit && !capable(CAP_IPC_LOCK)) { 412 pr_err("SEV: %lu locked pages exceed the lock limit of %lu.\n", locked, lock_limit); 413 return ERR_PTR(-ENOMEM); 414 } 415 416 if (WARN_ON_ONCE(npages > INT_MAX)) 417 return ERR_PTR(-EINVAL); 418 419 /* Avoid using vmalloc for smaller buffers. */ 420 size = npages * sizeof(struct page *); 421 if (size > PAGE_SIZE) 422 pages = __vmalloc(size, GFP_KERNEL_ACCOUNT | __GFP_ZERO); 423 else 424 pages = kmalloc(size, GFP_KERNEL_ACCOUNT); 425 426 if (!pages) 427 return ERR_PTR(-ENOMEM); 428 429 /* Pin the user virtual address. */ 430 npinned = pin_user_pages_fast(uaddr, npages, write ? FOLL_WRITE : 0, pages); 431 if (npinned != npages) { 432 pr_err("SEV: Failure locking %lu pages.\n", npages); 433 ret = -ENOMEM; 434 goto err; 435 } 436 437 *n = npages; 438 sev->pages_locked = locked; 439 440 return pages; 441 442 err: 443 if (npinned > 0) 444 unpin_user_pages(pages, npinned); 445 446 kvfree(pages); 447 return ERR_PTR(ret); 448 } 449 450 static void sev_unpin_memory(struct kvm *kvm, struct page **pages, 451 unsigned long npages) 452 { 453 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 454 455 unpin_user_pages(pages, npages); 456 kvfree(pages); 457 sev->pages_locked -= npages; 458 } 459 460 static void sev_clflush_pages(struct page *pages[], unsigned long npages) 461 { 462 uint8_t *page_virtual; 463 unsigned long i; 464 465 if (this_cpu_has(X86_FEATURE_SME_COHERENT) || npages == 0 || 466 pages == NULL) 467 return; 468 469 for (i = 0; i < npages; i++) { 470 page_virtual = kmap_local_page(pages[i]); 471 clflush_cache_range(page_virtual, PAGE_SIZE); 472 kunmap_local(page_virtual); 473 cond_resched(); 474 } 475 } 476 477 static unsigned long get_num_contig_pages(unsigned long idx, 478 struct page **inpages, unsigned long npages) 479 { 480 unsigned long paddr, next_paddr; 481 unsigned long i = idx + 1, pages = 1; 482 483 /* find the number of contiguous pages starting from idx */ 484 paddr = __sme_page_pa(inpages[idx]); 485 while (i < npages) { 486 next_paddr = __sme_page_pa(inpages[i++]); 487 if ((paddr + PAGE_SIZE) == next_paddr) { 488 pages++; 489 paddr = next_paddr; 490 continue; 491 } 492 break; 493 } 494 495 return pages; 496 } 497 498 static int sev_launch_update_data(struct kvm *kvm, struct kvm_sev_cmd *argp) 499 { 500 unsigned long vaddr, vaddr_end, next_vaddr, npages, pages, size, i; 501 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 502 struct kvm_sev_launch_update_data params; 503 struct sev_data_launch_update_data data; 504 struct page **inpages; 505 int ret; 506 507 if (!sev_guest(kvm)) 508 return -ENOTTY; 509 510 if (copy_from_user(¶ms, (void __user *)(uintptr_t)argp->data, sizeof(params))) 511 return -EFAULT; 512 513 vaddr = params.uaddr; 514 size = params.len; 515 vaddr_end = vaddr + size; 516 517 /* Lock the user memory. */ 518 inpages = sev_pin_memory(kvm, vaddr, size, &npages, 1); 519 if (IS_ERR(inpages)) 520 return PTR_ERR(inpages); 521 522 /* 523 * Flush (on non-coherent CPUs) before LAUNCH_UPDATE encrypts pages in 524 * place; the cache may contain the data that was written unencrypted. 525 */ 526 sev_clflush_pages(inpages, npages); 527 528 data.reserved = 0; 529 data.handle = sev->handle; 530 531 for (i = 0; vaddr < vaddr_end; vaddr = next_vaddr, i += pages) { 532 int offset, len; 533 534 /* 535 * If the user buffer is not page-aligned, calculate the offset 536 * within the page. 537 */ 538 offset = vaddr & (PAGE_SIZE - 1); 539 540 /* Calculate the number of pages that can be encrypted in one go. */ 541 pages = get_num_contig_pages(i, inpages, npages); 542 543 len = min_t(size_t, ((pages * PAGE_SIZE) - offset), size); 544 545 data.len = len; 546 data.address = __sme_page_pa(inpages[i]) + offset; 547 ret = sev_issue_cmd(kvm, SEV_CMD_LAUNCH_UPDATE_DATA, &data, &argp->error); 548 if (ret) 549 goto e_unpin; 550 551 size -= len; 552 next_vaddr = vaddr + len; 553 } 554 555 e_unpin: 556 /* content of memory is updated, mark pages dirty */ 557 for (i = 0; i < npages; i++) { 558 set_page_dirty_lock(inpages[i]); 559 mark_page_accessed(inpages[i]); 560 } 561 /* unlock the user pages */ 562 sev_unpin_memory(kvm, inpages, npages); 563 return ret; 564 } 565 566 static int sev_es_sync_vmsa(struct vcpu_svm *svm) 567 { 568 struct sev_es_save_area *save = svm->sev_es.vmsa; 569 570 /* Check some debug related fields before encrypting the VMSA */ 571 if (svm->vcpu.guest_debug || (svm->vmcb->save.dr7 & ~DR7_FIXED_1)) 572 return -EINVAL; 573 574 /* 575 * SEV-ES will use a VMSA that is pointed to by the VMCB, not 576 * the traditional VMSA that is part of the VMCB. Copy the 577 * traditional VMSA as it has been built so far (in prep 578 * for LAUNCH_UPDATE_VMSA) to be the initial SEV-ES state. 579 */ 580 memcpy(save, &svm->vmcb->save, sizeof(svm->vmcb->save)); 581 582 /* Sync registgers */ 583 save->rax = svm->vcpu.arch.regs[VCPU_REGS_RAX]; 584 save->rbx = svm->vcpu.arch.regs[VCPU_REGS_RBX]; 585 save->rcx = svm->vcpu.arch.regs[VCPU_REGS_RCX]; 586 save->rdx = svm->vcpu.arch.regs[VCPU_REGS_RDX]; 587 save->rsp = svm->vcpu.arch.regs[VCPU_REGS_RSP]; 588 save->rbp = svm->vcpu.arch.regs[VCPU_REGS_RBP]; 589 save->rsi = svm->vcpu.arch.regs[VCPU_REGS_RSI]; 590 save->rdi = svm->vcpu.arch.regs[VCPU_REGS_RDI]; 591 #ifdef CONFIG_X86_64 592 save->r8 = svm->vcpu.arch.regs[VCPU_REGS_R8]; 593 save->r9 = svm->vcpu.arch.regs[VCPU_REGS_R9]; 594 save->r10 = svm->vcpu.arch.regs[VCPU_REGS_R10]; 595 save->r11 = svm->vcpu.arch.regs[VCPU_REGS_R11]; 596 save->r12 = svm->vcpu.arch.regs[VCPU_REGS_R12]; 597 save->r13 = svm->vcpu.arch.regs[VCPU_REGS_R13]; 598 save->r14 = svm->vcpu.arch.regs[VCPU_REGS_R14]; 599 save->r15 = svm->vcpu.arch.regs[VCPU_REGS_R15]; 600 #endif 601 save->rip = svm->vcpu.arch.regs[VCPU_REGS_RIP]; 602 603 /* Sync some non-GPR registers before encrypting */ 604 save->xcr0 = svm->vcpu.arch.xcr0; 605 save->pkru = svm->vcpu.arch.pkru; 606 save->xss = svm->vcpu.arch.ia32_xss; 607 save->dr6 = svm->vcpu.arch.dr6; 608 609 pr_debug("Virtual Machine Save Area (VMSA):\n"); 610 print_hex_dump_debug("", DUMP_PREFIX_NONE, 16, 1, save, sizeof(*save), false); 611 612 return 0; 613 } 614 615 static int __sev_launch_update_vmsa(struct kvm *kvm, struct kvm_vcpu *vcpu, 616 int *error) 617 { 618 struct sev_data_launch_update_vmsa vmsa; 619 struct vcpu_svm *svm = to_svm(vcpu); 620 int ret; 621 622 /* Perform some pre-encryption checks against the VMSA */ 623 ret = sev_es_sync_vmsa(svm); 624 if (ret) 625 return ret; 626 627 /* 628 * The LAUNCH_UPDATE_VMSA command will perform in-place encryption of 629 * the VMSA memory content (i.e it will write the same memory region 630 * with the guest's key), so invalidate it first. 631 */ 632 clflush_cache_range(svm->sev_es.vmsa, PAGE_SIZE); 633 634 vmsa.reserved = 0; 635 vmsa.handle = to_kvm_svm(kvm)->sev_info.handle; 636 vmsa.address = __sme_pa(svm->sev_es.vmsa); 637 vmsa.len = PAGE_SIZE; 638 ret = sev_issue_cmd(kvm, SEV_CMD_LAUNCH_UPDATE_VMSA, &vmsa, error); 639 if (ret) 640 return ret; 641 642 vcpu->arch.guest_state_protected = true; 643 return 0; 644 } 645 646 static int sev_launch_update_vmsa(struct kvm *kvm, struct kvm_sev_cmd *argp) 647 { 648 struct kvm_vcpu *vcpu; 649 unsigned long i; 650 int ret; 651 652 if (!sev_es_guest(kvm)) 653 return -ENOTTY; 654 655 kvm_for_each_vcpu(i, vcpu, kvm) { 656 ret = mutex_lock_killable(&vcpu->mutex); 657 if (ret) 658 return ret; 659 660 ret = __sev_launch_update_vmsa(kvm, vcpu, &argp->error); 661 662 mutex_unlock(&vcpu->mutex); 663 if (ret) 664 return ret; 665 } 666 667 return 0; 668 } 669 670 static int sev_launch_measure(struct kvm *kvm, struct kvm_sev_cmd *argp) 671 { 672 void __user *measure = (void __user *)(uintptr_t)argp->data; 673 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 674 struct sev_data_launch_measure data; 675 struct kvm_sev_launch_measure params; 676 void __user *p = NULL; 677 void *blob = NULL; 678 int ret; 679 680 if (!sev_guest(kvm)) 681 return -ENOTTY; 682 683 if (copy_from_user(¶ms, measure, sizeof(params))) 684 return -EFAULT; 685 686 memset(&data, 0, sizeof(data)); 687 688 /* User wants to query the blob length */ 689 if (!params.len) 690 goto cmd; 691 692 p = (void __user *)(uintptr_t)params.uaddr; 693 if (p) { 694 if (params.len > SEV_FW_BLOB_MAX_SIZE) 695 return -EINVAL; 696 697 blob = kzalloc(params.len, GFP_KERNEL_ACCOUNT); 698 if (!blob) 699 return -ENOMEM; 700 701 data.address = __psp_pa(blob); 702 data.len = params.len; 703 } 704 705 cmd: 706 data.handle = sev->handle; 707 ret = sev_issue_cmd(kvm, SEV_CMD_LAUNCH_MEASURE, &data, &argp->error); 708 709 /* 710 * If we query the session length, FW responded with expected data. 711 */ 712 if (!params.len) 713 goto done; 714 715 if (ret) 716 goto e_free_blob; 717 718 if (blob) { 719 if (copy_to_user(p, blob, params.len)) 720 ret = -EFAULT; 721 } 722 723 done: 724 params.len = data.len; 725 if (copy_to_user(measure, ¶ms, sizeof(params))) 726 ret = -EFAULT; 727 e_free_blob: 728 kfree(blob); 729 return ret; 730 } 731 732 static int sev_launch_finish(struct kvm *kvm, struct kvm_sev_cmd *argp) 733 { 734 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 735 struct sev_data_launch_finish data; 736 737 if (!sev_guest(kvm)) 738 return -ENOTTY; 739 740 data.handle = sev->handle; 741 return sev_issue_cmd(kvm, SEV_CMD_LAUNCH_FINISH, &data, &argp->error); 742 } 743 744 static int sev_guest_status(struct kvm *kvm, struct kvm_sev_cmd *argp) 745 { 746 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 747 struct kvm_sev_guest_status params; 748 struct sev_data_guest_status data; 749 int ret; 750 751 if (!sev_guest(kvm)) 752 return -ENOTTY; 753 754 memset(&data, 0, sizeof(data)); 755 756 data.handle = sev->handle; 757 ret = sev_issue_cmd(kvm, SEV_CMD_GUEST_STATUS, &data, &argp->error); 758 if (ret) 759 return ret; 760 761 params.policy = data.policy; 762 params.state = data.state; 763 params.handle = data.handle; 764 765 if (copy_to_user((void __user *)(uintptr_t)argp->data, ¶ms, sizeof(params))) 766 ret = -EFAULT; 767 768 return ret; 769 } 770 771 static int __sev_issue_dbg_cmd(struct kvm *kvm, unsigned long src, 772 unsigned long dst, int size, 773 int *error, bool enc) 774 { 775 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 776 struct sev_data_dbg data; 777 778 data.reserved = 0; 779 data.handle = sev->handle; 780 data.dst_addr = dst; 781 data.src_addr = src; 782 data.len = size; 783 784 return sev_issue_cmd(kvm, 785 enc ? SEV_CMD_DBG_ENCRYPT : SEV_CMD_DBG_DECRYPT, 786 &data, error); 787 } 788 789 static int __sev_dbg_decrypt(struct kvm *kvm, unsigned long src_paddr, 790 unsigned long dst_paddr, int sz, int *err) 791 { 792 int offset; 793 794 /* 795 * Its safe to read more than we are asked, caller should ensure that 796 * destination has enough space. 797 */ 798 offset = src_paddr & 15; 799 src_paddr = round_down(src_paddr, 16); 800 sz = round_up(sz + offset, 16); 801 802 return __sev_issue_dbg_cmd(kvm, src_paddr, dst_paddr, sz, err, false); 803 } 804 805 static int __sev_dbg_decrypt_user(struct kvm *kvm, unsigned long paddr, 806 void __user *dst_uaddr, 807 unsigned long dst_paddr, 808 int size, int *err) 809 { 810 struct page *tpage = NULL; 811 int ret, offset; 812 813 /* if inputs are not 16-byte then use intermediate buffer */ 814 if (!IS_ALIGNED(dst_paddr, 16) || 815 !IS_ALIGNED(paddr, 16) || 816 !IS_ALIGNED(size, 16)) { 817 tpage = (void *)alloc_page(GFP_KERNEL_ACCOUNT | __GFP_ZERO); 818 if (!tpage) 819 return -ENOMEM; 820 821 dst_paddr = __sme_page_pa(tpage); 822 } 823 824 ret = __sev_dbg_decrypt(kvm, paddr, dst_paddr, size, err); 825 if (ret) 826 goto e_free; 827 828 if (tpage) { 829 offset = paddr & 15; 830 if (copy_to_user(dst_uaddr, page_address(tpage) + offset, size)) 831 ret = -EFAULT; 832 } 833 834 e_free: 835 if (tpage) 836 __free_page(tpage); 837 838 return ret; 839 } 840 841 static int __sev_dbg_encrypt_user(struct kvm *kvm, unsigned long paddr, 842 void __user *vaddr, 843 unsigned long dst_paddr, 844 void __user *dst_vaddr, 845 int size, int *error) 846 { 847 struct page *src_tpage = NULL; 848 struct page *dst_tpage = NULL; 849 int ret, len = size; 850 851 /* If source buffer is not aligned then use an intermediate buffer */ 852 if (!IS_ALIGNED((unsigned long)vaddr, 16)) { 853 src_tpage = alloc_page(GFP_KERNEL_ACCOUNT); 854 if (!src_tpage) 855 return -ENOMEM; 856 857 if (copy_from_user(page_address(src_tpage), vaddr, size)) { 858 __free_page(src_tpage); 859 return -EFAULT; 860 } 861 862 paddr = __sme_page_pa(src_tpage); 863 } 864 865 /* 866 * If destination buffer or length is not aligned then do read-modify-write: 867 * - decrypt destination in an intermediate buffer 868 * - copy the source buffer in an intermediate buffer 869 * - use the intermediate buffer as source buffer 870 */ 871 if (!IS_ALIGNED((unsigned long)dst_vaddr, 16) || !IS_ALIGNED(size, 16)) { 872 int dst_offset; 873 874 dst_tpage = alloc_page(GFP_KERNEL_ACCOUNT); 875 if (!dst_tpage) { 876 ret = -ENOMEM; 877 goto e_free; 878 } 879 880 ret = __sev_dbg_decrypt(kvm, dst_paddr, 881 __sme_page_pa(dst_tpage), size, error); 882 if (ret) 883 goto e_free; 884 885 /* 886 * If source is kernel buffer then use memcpy() otherwise 887 * copy_from_user(). 888 */ 889 dst_offset = dst_paddr & 15; 890 891 if (src_tpage) 892 memcpy(page_address(dst_tpage) + dst_offset, 893 page_address(src_tpage), size); 894 else { 895 if (copy_from_user(page_address(dst_tpage) + dst_offset, 896 vaddr, size)) { 897 ret = -EFAULT; 898 goto e_free; 899 } 900 } 901 902 paddr = __sme_page_pa(dst_tpage); 903 dst_paddr = round_down(dst_paddr, 16); 904 len = round_up(size, 16); 905 } 906 907 ret = __sev_issue_dbg_cmd(kvm, paddr, dst_paddr, len, error, true); 908 909 e_free: 910 if (src_tpage) 911 __free_page(src_tpage); 912 if (dst_tpage) 913 __free_page(dst_tpage); 914 return ret; 915 } 916 917 static int sev_dbg_crypt(struct kvm *kvm, struct kvm_sev_cmd *argp, bool dec) 918 { 919 unsigned long vaddr, vaddr_end, next_vaddr; 920 unsigned long dst_vaddr; 921 struct page **src_p, **dst_p; 922 struct kvm_sev_dbg debug; 923 unsigned long n; 924 unsigned int size; 925 int ret; 926 927 if (!sev_guest(kvm)) 928 return -ENOTTY; 929 930 if (copy_from_user(&debug, (void __user *)(uintptr_t)argp->data, sizeof(debug))) 931 return -EFAULT; 932 933 if (!debug.len || debug.src_uaddr + debug.len < debug.src_uaddr) 934 return -EINVAL; 935 if (!debug.dst_uaddr) 936 return -EINVAL; 937 938 vaddr = debug.src_uaddr; 939 size = debug.len; 940 vaddr_end = vaddr + size; 941 dst_vaddr = debug.dst_uaddr; 942 943 for (; vaddr < vaddr_end; vaddr = next_vaddr) { 944 int len, s_off, d_off; 945 946 /* lock userspace source and destination page */ 947 src_p = sev_pin_memory(kvm, vaddr & PAGE_MASK, PAGE_SIZE, &n, 0); 948 if (IS_ERR(src_p)) 949 return PTR_ERR(src_p); 950 951 dst_p = sev_pin_memory(kvm, dst_vaddr & PAGE_MASK, PAGE_SIZE, &n, 1); 952 if (IS_ERR(dst_p)) { 953 sev_unpin_memory(kvm, src_p, n); 954 return PTR_ERR(dst_p); 955 } 956 957 /* 958 * Flush (on non-coherent CPUs) before DBG_{DE,EN}CRYPT read or modify 959 * the pages; flush the destination too so that future accesses do not 960 * see stale data. 961 */ 962 sev_clflush_pages(src_p, 1); 963 sev_clflush_pages(dst_p, 1); 964 965 /* 966 * Since user buffer may not be page aligned, calculate the 967 * offset within the page. 968 */ 969 s_off = vaddr & ~PAGE_MASK; 970 d_off = dst_vaddr & ~PAGE_MASK; 971 len = min_t(size_t, (PAGE_SIZE - s_off), size); 972 973 if (dec) 974 ret = __sev_dbg_decrypt_user(kvm, 975 __sme_page_pa(src_p[0]) + s_off, 976 (void __user *)dst_vaddr, 977 __sme_page_pa(dst_p[0]) + d_off, 978 len, &argp->error); 979 else 980 ret = __sev_dbg_encrypt_user(kvm, 981 __sme_page_pa(src_p[0]) + s_off, 982 (void __user *)vaddr, 983 __sme_page_pa(dst_p[0]) + d_off, 984 (void __user *)dst_vaddr, 985 len, &argp->error); 986 987 sev_unpin_memory(kvm, src_p, n); 988 sev_unpin_memory(kvm, dst_p, n); 989 990 if (ret) 991 goto err; 992 993 next_vaddr = vaddr + len; 994 dst_vaddr = dst_vaddr + len; 995 size -= len; 996 } 997 err: 998 return ret; 999 } 1000 1001 static int sev_launch_secret(struct kvm *kvm, struct kvm_sev_cmd *argp) 1002 { 1003 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 1004 struct sev_data_launch_secret data; 1005 struct kvm_sev_launch_secret params; 1006 struct page **pages; 1007 void *blob, *hdr; 1008 unsigned long n, i; 1009 int ret, offset; 1010 1011 if (!sev_guest(kvm)) 1012 return -ENOTTY; 1013 1014 if (copy_from_user(¶ms, (void __user *)(uintptr_t)argp->data, sizeof(params))) 1015 return -EFAULT; 1016 1017 pages = sev_pin_memory(kvm, params.guest_uaddr, params.guest_len, &n, 1); 1018 if (IS_ERR(pages)) 1019 return PTR_ERR(pages); 1020 1021 /* 1022 * Flush (on non-coherent CPUs) before LAUNCH_SECRET encrypts pages in 1023 * place; the cache may contain the data that was written unencrypted. 1024 */ 1025 sev_clflush_pages(pages, n); 1026 1027 /* 1028 * The secret must be copied into contiguous memory region, lets verify 1029 * that userspace memory pages are contiguous before we issue command. 1030 */ 1031 if (get_num_contig_pages(0, pages, n) != n) { 1032 ret = -EINVAL; 1033 goto e_unpin_memory; 1034 } 1035 1036 memset(&data, 0, sizeof(data)); 1037 1038 offset = params.guest_uaddr & (PAGE_SIZE - 1); 1039 data.guest_address = __sme_page_pa(pages[0]) + offset; 1040 data.guest_len = params.guest_len; 1041 1042 blob = psp_copy_user_blob(params.trans_uaddr, params.trans_len); 1043 if (IS_ERR(blob)) { 1044 ret = PTR_ERR(blob); 1045 goto e_unpin_memory; 1046 } 1047 1048 data.trans_address = __psp_pa(blob); 1049 data.trans_len = params.trans_len; 1050 1051 hdr = psp_copy_user_blob(params.hdr_uaddr, params.hdr_len); 1052 if (IS_ERR(hdr)) { 1053 ret = PTR_ERR(hdr); 1054 goto e_free_blob; 1055 } 1056 data.hdr_address = __psp_pa(hdr); 1057 data.hdr_len = params.hdr_len; 1058 1059 data.handle = sev->handle; 1060 ret = sev_issue_cmd(kvm, SEV_CMD_LAUNCH_UPDATE_SECRET, &data, &argp->error); 1061 1062 kfree(hdr); 1063 1064 e_free_blob: 1065 kfree(blob); 1066 e_unpin_memory: 1067 /* content of memory is updated, mark pages dirty */ 1068 for (i = 0; i < n; i++) { 1069 set_page_dirty_lock(pages[i]); 1070 mark_page_accessed(pages[i]); 1071 } 1072 sev_unpin_memory(kvm, pages, n); 1073 return ret; 1074 } 1075 1076 static int sev_get_attestation_report(struct kvm *kvm, struct kvm_sev_cmd *argp) 1077 { 1078 void __user *report = (void __user *)(uintptr_t)argp->data; 1079 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 1080 struct sev_data_attestation_report data; 1081 struct kvm_sev_attestation_report params; 1082 void __user *p; 1083 void *blob = NULL; 1084 int ret; 1085 1086 if (!sev_guest(kvm)) 1087 return -ENOTTY; 1088 1089 if (copy_from_user(¶ms, (void __user *)(uintptr_t)argp->data, sizeof(params))) 1090 return -EFAULT; 1091 1092 memset(&data, 0, sizeof(data)); 1093 1094 /* User wants to query the blob length */ 1095 if (!params.len) 1096 goto cmd; 1097 1098 p = (void __user *)(uintptr_t)params.uaddr; 1099 if (p) { 1100 if (params.len > SEV_FW_BLOB_MAX_SIZE) 1101 return -EINVAL; 1102 1103 blob = kzalloc(params.len, GFP_KERNEL_ACCOUNT); 1104 if (!blob) 1105 return -ENOMEM; 1106 1107 data.address = __psp_pa(blob); 1108 data.len = params.len; 1109 memcpy(data.mnonce, params.mnonce, sizeof(params.mnonce)); 1110 } 1111 cmd: 1112 data.handle = sev->handle; 1113 ret = sev_issue_cmd(kvm, SEV_CMD_ATTESTATION_REPORT, &data, &argp->error); 1114 /* 1115 * If we query the session length, FW responded with expected data. 1116 */ 1117 if (!params.len) 1118 goto done; 1119 1120 if (ret) 1121 goto e_free_blob; 1122 1123 if (blob) { 1124 if (copy_to_user(p, blob, params.len)) 1125 ret = -EFAULT; 1126 } 1127 1128 done: 1129 params.len = data.len; 1130 if (copy_to_user(report, ¶ms, sizeof(params))) 1131 ret = -EFAULT; 1132 e_free_blob: 1133 kfree(blob); 1134 return ret; 1135 } 1136 1137 /* Userspace wants to query session length. */ 1138 static int 1139 __sev_send_start_query_session_length(struct kvm *kvm, struct kvm_sev_cmd *argp, 1140 struct kvm_sev_send_start *params) 1141 { 1142 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 1143 struct sev_data_send_start data; 1144 int ret; 1145 1146 memset(&data, 0, sizeof(data)); 1147 data.handle = sev->handle; 1148 ret = sev_issue_cmd(kvm, SEV_CMD_SEND_START, &data, &argp->error); 1149 1150 params->session_len = data.session_len; 1151 if (copy_to_user((void __user *)(uintptr_t)argp->data, params, 1152 sizeof(struct kvm_sev_send_start))) 1153 ret = -EFAULT; 1154 1155 return ret; 1156 } 1157 1158 static int sev_send_start(struct kvm *kvm, struct kvm_sev_cmd *argp) 1159 { 1160 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 1161 struct sev_data_send_start data; 1162 struct kvm_sev_send_start params; 1163 void *amd_certs, *session_data; 1164 void *pdh_cert, *plat_certs; 1165 int ret; 1166 1167 if (!sev_guest(kvm)) 1168 return -ENOTTY; 1169 1170 if (copy_from_user(¶ms, (void __user *)(uintptr_t)argp->data, 1171 sizeof(struct kvm_sev_send_start))) 1172 return -EFAULT; 1173 1174 /* if session_len is zero, userspace wants to query the session length */ 1175 if (!params.session_len) 1176 return __sev_send_start_query_session_length(kvm, argp, 1177 ¶ms); 1178 1179 /* some sanity checks */ 1180 if (!params.pdh_cert_uaddr || !params.pdh_cert_len || 1181 !params.session_uaddr || params.session_len > SEV_FW_BLOB_MAX_SIZE) 1182 return -EINVAL; 1183 1184 /* allocate the memory to hold the session data blob */ 1185 session_data = kzalloc(params.session_len, GFP_KERNEL_ACCOUNT); 1186 if (!session_data) 1187 return -ENOMEM; 1188 1189 /* copy the certificate blobs from userspace */ 1190 pdh_cert = psp_copy_user_blob(params.pdh_cert_uaddr, 1191 params.pdh_cert_len); 1192 if (IS_ERR(pdh_cert)) { 1193 ret = PTR_ERR(pdh_cert); 1194 goto e_free_session; 1195 } 1196 1197 plat_certs = psp_copy_user_blob(params.plat_certs_uaddr, 1198 params.plat_certs_len); 1199 if (IS_ERR(plat_certs)) { 1200 ret = PTR_ERR(plat_certs); 1201 goto e_free_pdh; 1202 } 1203 1204 amd_certs = psp_copy_user_blob(params.amd_certs_uaddr, 1205 params.amd_certs_len); 1206 if (IS_ERR(amd_certs)) { 1207 ret = PTR_ERR(amd_certs); 1208 goto e_free_plat_cert; 1209 } 1210 1211 /* populate the FW SEND_START field with system physical address */ 1212 memset(&data, 0, sizeof(data)); 1213 data.pdh_cert_address = __psp_pa(pdh_cert); 1214 data.pdh_cert_len = params.pdh_cert_len; 1215 data.plat_certs_address = __psp_pa(plat_certs); 1216 data.plat_certs_len = params.plat_certs_len; 1217 data.amd_certs_address = __psp_pa(amd_certs); 1218 data.amd_certs_len = params.amd_certs_len; 1219 data.session_address = __psp_pa(session_data); 1220 data.session_len = params.session_len; 1221 data.handle = sev->handle; 1222 1223 ret = sev_issue_cmd(kvm, SEV_CMD_SEND_START, &data, &argp->error); 1224 1225 if (!ret && copy_to_user((void __user *)(uintptr_t)params.session_uaddr, 1226 session_data, params.session_len)) { 1227 ret = -EFAULT; 1228 goto e_free_amd_cert; 1229 } 1230 1231 params.policy = data.policy; 1232 params.session_len = data.session_len; 1233 if (copy_to_user((void __user *)(uintptr_t)argp->data, ¶ms, 1234 sizeof(struct kvm_sev_send_start))) 1235 ret = -EFAULT; 1236 1237 e_free_amd_cert: 1238 kfree(amd_certs); 1239 e_free_plat_cert: 1240 kfree(plat_certs); 1241 e_free_pdh: 1242 kfree(pdh_cert); 1243 e_free_session: 1244 kfree(session_data); 1245 return ret; 1246 } 1247 1248 /* Userspace wants to query either header or trans length. */ 1249 static int 1250 __sev_send_update_data_query_lengths(struct kvm *kvm, struct kvm_sev_cmd *argp, 1251 struct kvm_sev_send_update_data *params) 1252 { 1253 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 1254 struct sev_data_send_update_data data; 1255 int ret; 1256 1257 memset(&data, 0, sizeof(data)); 1258 data.handle = sev->handle; 1259 ret = sev_issue_cmd(kvm, SEV_CMD_SEND_UPDATE_DATA, &data, &argp->error); 1260 1261 params->hdr_len = data.hdr_len; 1262 params->trans_len = data.trans_len; 1263 1264 if (copy_to_user((void __user *)(uintptr_t)argp->data, params, 1265 sizeof(struct kvm_sev_send_update_data))) 1266 ret = -EFAULT; 1267 1268 return ret; 1269 } 1270 1271 static int sev_send_update_data(struct kvm *kvm, struct kvm_sev_cmd *argp) 1272 { 1273 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 1274 struct sev_data_send_update_data data; 1275 struct kvm_sev_send_update_data params; 1276 void *hdr, *trans_data; 1277 struct page **guest_page; 1278 unsigned long n; 1279 int ret, offset; 1280 1281 if (!sev_guest(kvm)) 1282 return -ENOTTY; 1283 1284 if (copy_from_user(¶ms, (void __user *)(uintptr_t)argp->data, 1285 sizeof(struct kvm_sev_send_update_data))) 1286 return -EFAULT; 1287 1288 /* userspace wants to query either header or trans length */ 1289 if (!params.trans_len || !params.hdr_len) 1290 return __sev_send_update_data_query_lengths(kvm, argp, ¶ms); 1291 1292 if (!params.trans_uaddr || !params.guest_uaddr || 1293 !params.guest_len || !params.hdr_uaddr) 1294 return -EINVAL; 1295 1296 /* Check if we are crossing the page boundary */ 1297 offset = params.guest_uaddr & (PAGE_SIZE - 1); 1298 if (params.guest_len > PAGE_SIZE || (params.guest_len + offset) > PAGE_SIZE) 1299 return -EINVAL; 1300 1301 /* Pin guest memory */ 1302 guest_page = sev_pin_memory(kvm, params.guest_uaddr & PAGE_MASK, 1303 PAGE_SIZE, &n, 0); 1304 if (IS_ERR(guest_page)) 1305 return PTR_ERR(guest_page); 1306 1307 /* allocate memory for header and transport buffer */ 1308 ret = -ENOMEM; 1309 hdr = kzalloc(params.hdr_len, GFP_KERNEL_ACCOUNT); 1310 if (!hdr) 1311 goto e_unpin; 1312 1313 trans_data = kzalloc(params.trans_len, GFP_KERNEL_ACCOUNT); 1314 if (!trans_data) 1315 goto e_free_hdr; 1316 1317 memset(&data, 0, sizeof(data)); 1318 data.hdr_address = __psp_pa(hdr); 1319 data.hdr_len = params.hdr_len; 1320 data.trans_address = __psp_pa(trans_data); 1321 data.trans_len = params.trans_len; 1322 1323 /* The SEND_UPDATE_DATA command requires C-bit to be always set. */ 1324 data.guest_address = (page_to_pfn(guest_page[0]) << PAGE_SHIFT) + offset; 1325 data.guest_address |= sev_me_mask; 1326 data.guest_len = params.guest_len; 1327 data.handle = sev->handle; 1328 1329 ret = sev_issue_cmd(kvm, SEV_CMD_SEND_UPDATE_DATA, &data, &argp->error); 1330 1331 if (ret) 1332 goto e_free_trans_data; 1333 1334 /* copy transport buffer to user space */ 1335 if (copy_to_user((void __user *)(uintptr_t)params.trans_uaddr, 1336 trans_data, params.trans_len)) { 1337 ret = -EFAULT; 1338 goto e_free_trans_data; 1339 } 1340 1341 /* Copy packet header to userspace. */ 1342 if (copy_to_user((void __user *)(uintptr_t)params.hdr_uaddr, hdr, 1343 params.hdr_len)) 1344 ret = -EFAULT; 1345 1346 e_free_trans_data: 1347 kfree(trans_data); 1348 e_free_hdr: 1349 kfree(hdr); 1350 e_unpin: 1351 sev_unpin_memory(kvm, guest_page, n); 1352 1353 return ret; 1354 } 1355 1356 static int sev_send_finish(struct kvm *kvm, struct kvm_sev_cmd *argp) 1357 { 1358 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 1359 struct sev_data_send_finish data; 1360 1361 if (!sev_guest(kvm)) 1362 return -ENOTTY; 1363 1364 data.handle = sev->handle; 1365 return sev_issue_cmd(kvm, SEV_CMD_SEND_FINISH, &data, &argp->error); 1366 } 1367 1368 static int sev_send_cancel(struct kvm *kvm, struct kvm_sev_cmd *argp) 1369 { 1370 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 1371 struct sev_data_send_cancel data; 1372 1373 if (!sev_guest(kvm)) 1374 return -ENOTTY; 1375 1376 data.handle = sev->handle; 1377 return sev_issue_cmd(kvm, SEV_CMD_SEND_CANCEL, &data, &argp->error); 1378 } 1379 1380 static int sev_receive_start(struct kvm *kvm, struct kvm_sev_cmd *argp) 1381 { 1382 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 1383 struct sev_data_receive_start start; 1384 struct kvm_sev_receive_start params; 1385 int *error = &argp->error; 1386 void *session_data; 1387 void *pdh_data; 1388 int ret; 1389 1390 if (!sev_guest(kvm)) 1391 return -ENOTTY; 1392 1393 /* Get parameter from the userspace */ 1394 if (copy_from_user(¶ms, (void __user *)(uintptr_t)argp->data, 1395 sizeof(struct kvm_sev_receive_start))) 1396 return -EFAULT; 1397 1398 /* some sanity checks */ 1399 if (!params.pdh_uaddr || !params.pdh_len || 1400 !params.session_uaddr || !params.session_len) 1401 return -EINVAL; 1402 1403 pdh_data = psp_copy_user_blob(params.pdh_uaddr, params.pdh_len); 1404 if (IS_ERR(pdh_data)) 1405 return PTR_ERR(pdh_data); 1406 1407 session_data = psp_copy_user_blob(params.session_uaddr, 1408 params.session_len); 1409 if (IS_ERR(session_data)) { 1410 ret = PTR_ERR(session_data); 1411 goto e_free_pdh; 1412 } 1413 1414 memset(&start, 0, sizeof(start)); 1415 start.handle = params.handle; 1416 start.policy = params.policy; 1417 start.pdh_cert_address = __psp_pa(pdh_data); 1418 start.pdh_cert_len = params.pdh_len; 1419 start.session_address = __psp_pa(session_data); 1420 start.session_len = params.session_len; 1421 1422 /* create memory encryption context */ 1423 ret = __sev_issue_cmd(argp->sev_fd, SEV_CMD_RECEIVE_START, &start, 1424 error); 1425 if (ret) 1426 goto e_free_session; 1427 1428 /* Bind ASID to this guest */ 1429 ret = sev_bind_asid(kvm, start.handle, error); 1430 if (ret) { 1431 sev_decommission(start.handle); 1432 goto e_free_session; 1433 } 1434 1435 params.handle = start.handle; 1436 if (copy_to_user((void __user *)(uintptr_t)argp->data, 1437 ¶ms, sizeof(struct kvm_sev_receive_start))) { 1438 ret = -EFAULT; 1439 sev_unbind_asid(kvm, start.handle); 1440 goto e_free_session; 1441 } 1442 1443 sev->handle = start.handle; 1444 sev->fd = argp->sev_fd; 1445 1446 e_free_session: 1447 kfree(session_data); 1448 e_free_pdh: 1449 kfree(pdh_data); 1450 1451 return ret; 1452 } 1453 1454 static int sev_receive_update_data(struct kvm *kvm, struct kvm_sev_cmd *argp) 1455 { 1456 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 1457 struct kvm_sev_receive_update_data params; 1458 struct sev_data_receive_update_data data; 1459 void *hdr = NULL, *trans = NULL; 1460 struct page **guest_page; 1461 unsigned long n; 1462 int ret, offset; 1463 1464 if (!sev_guest(kvm)) 1465 return -EINVAL; 1466 1467 if (copy_from_user(¶ms, (void __user *)(uintptr_t)argp->data, 1468 sizeof(struct kvm_sev_receive_update_data))) 1469 return -EFAULT; 1470 1471 if (!params.hdr_uaddr || !params.hdr_len || 1472 !params.guest_uaddr || !params.guest_len || 1473 !params.trans_uaddr || !params.trans_len) 1474 return -EINVAL; 1475 1476 /* Check if we are crossing the page boundary */ 1477 offset = params.guest_uaddr & (PAGE_SIZE - 1); 1478 if (params.guest_len > PAGE_SIZE || (params.guest_len + offset) > PAGE_SIZE) 1479 return -EINVAL; 1480 1481 hdr = psp_copy_user_blob(params.hdr_uaddr, params.hdr_len); 1482 if (IS_ERR(hdr)) 1483 return PTR_ERR(hdr); 1484 1485 trans = psp_copy_user_blob(params.trans_uaddr, params.trans_len); 1486 if (IS_ERR(trans)) { 1487 ret = PTR_ERR(trans); 1488 goto e_free_hdr; 1489 } 1490 1491 memset(&data, 0, sizeof(data)); 1492 data.hdr_address = __psp_pa(hdr); 1493 data.hdr_len = params.hdr_len; 1494 data.trans_address = __psp_pa(trans); 1495 data.trans_len = params.trans_len; 1496 1497 /* Pin guest memory */ 1498 guest_page = sev_pin_memory(kvm, params.guest_uaddr & PAGE_MASK, 1499 PAGE_SIZE, &n, 1); 1500 if (IS_ERR(guest_page)) { 1501 ret = PTR_ERR(guest_page); 1502 goto e_free_trans; 1503 } 1504 1505 /* 1506 * Flush (on non-coherent CPUs) before RECEIVE_UPDATE_DATA, the PSP 1507 * encrypts the written data with the guest's key, and the cache may 1508 * contain dirty, unencrypted data. 1509 */ 1510 sev_clflush_pages(guest_page, n); 1511 1512 /* The RECEIVE_UPDATE_DATA command requires C-bit to be always set. */ 1513 data.guest_address = (page_to_pfn(guest_page[0]) << PAGE_SHIFT) + offset; 1514 data.guest_address |= sev_me_mask; 1515 data.guest_len = params.guest_len; 1516 data.handle = sev->handle; 1517 1518 ret = sev_issue_cmd(kvm, SEV_CMD_RECEIVE_UPDATE_DATA, &data, 1519 &argp->error); 1520 1521 sev_unpin_memory(kvm, guest_page, n); 1522 1523 e_free_trans: 1524 kfree(trans); 1525 e_free_hdr: 1526 kfree(hdr); 1527 1528 return ret; 1529 } 1530 1531 static int sev_receive_finish(struct kvm *kvm, struct kvm_sev_cmd *argp) 1532 { 1533 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 1534 struct sev_data_receive_finish data; 1535 1536 if (!sev_guest(kvm)) 1537 return -ENOTTY; 1538 1539 data.handle = sev->handle; 1540 return sev_issue_cmd(kvm, SEV_CMD_RECEIVE_FINISH, &data, &argp->error); 1541 } 1542 1543 static bool is_cmd_allowed_from_mirror(u32 cmd_id) 1544 { 1545 /* 1546 * Allow mirrors VM to call KVM_SEV_LAUNCH_UPDATE_VMSA to enable SEV-ES 1547 * active mirror VMs. Also allow the debugging and status commands. 1548 */ 1549 if (cmd_id == KVM_SEV_LAUNCH_UPDATE_VMSA || 1550 cmd_id == KVM_SEV_GUEST_STATUS || cmd_id == KVM_SEV_DBG_DECRYPT || 1551 cmd_id == KVM_SEV_DBG_ENCRYPT) 1552 return true; 1553 1554 return false; 1555 } 1556 1557 static int sev_lock_two_vms(struct kvm *dst_kvm, struct kvm *src_kvm) 1558 { 1559 struct kvm_sev_info *dst_sev = &to_kvm_svm(dst_kvm)->sev_info; 1560 struct kvm_sev_info *src_sev = &to_kvm_svm(src_kvm)->sev_info; 1561 int r = -EBUSY; 1562 1563 if (dst_kvm == src_kvm) 1564 return -EINVAL; 1565 1566 /* 1567 * Bail if these VMs are already involved in a migration to avoid 1568 * deadlock between two VMs trying to migrate to/from each other. 1569 */ 1570 if (atomic_cmpxchg_acquire(&dst_sev->migration_in_progress, 0, 1)) 1571 return -EBUSY; 1572 1573 if (atomic_cmpxchg_acquire(&src_sev->migration_in_progress, 0, 1)) 1574 goto release_dst; 1575 1576 r = -EINTR; 1577 if (mutex_lock_killable(&dst_kvm->lock)) 1578 goto release_src; 1579 if (mutex_lock_killable_nested(&src_kvm->lock, SINGLE_DEPTH_NESTING)) 1580 goto unlock_dst; 1581 return 0; 1582 1583 unlock_dst: 1584 mutex_unlock(&dst_kvm->lock); 1585 release_src: 1586 atomic_set_release(&src_sev->migration_in_progress, 0); 1587 release_dst: 1588 atomic_set_release(&dst_sev->migration_in_progress, 0); 1589 return r; 1590 } 1591 1592 static void sev_unlock_two_vms(struct kvm *dst_kvm, struct kvm *src_kvm) 1593 { 1594 struct kvm_sev_info *dst_sev = &to_kvm_svm(dst_kvm)->sev_info; 1595 struct kvm_sev_info *src_sev = &to_kvm_svm(src_kvm)->sev_info; 1596 1597 mutex_unlock(&dst_kvm->lock); 1598 mutex_unlock(&src_kvm->lock); 1599 atomic_set_release(&dst_sev->migration_in_progress, 0); 1600 atomic_set_release(&src_sev->migration_in_progress, 0); 1601 } 1602 1603 /* vCPU mutex subclasses. */ 1604 enum sev_migration_role { 1605 SEV_MIGRATION_SOURCE = 0, 1606 SEV_MIGRATION_TARGET, 1607 SEV_NR_MIGRATION_ROLES, 1608 }; 1609 1610 static int sev_lock_vcpus_for_migration(struct kvm *kvm, 1611 enum sev_migration_role role) 1612 { 1613 struct kvm_vcpu *vcpu; 1614 unsigned long i, j; 1615 1616 kvm_for_each_vcpu(i, vcpu, kvm) { 1617 if (mutex_lock_killable_nested(&vcpu->mutex, role)) 1618 goto out_unlock; 1619 1620 #ifdef CONFIG_PROVE_LOCKING 1621 if (!i) 1622 /* 1623 * Reset the role to one that avoids colliding with 1624 * the role used for the first vcpu mutex. 1625 */ 1626 role = SEV_NR_MIGRATION_ROLES; 1627 else 1628 mutex_release(&vcpu->mutex.dep_map, _THIS_IP_); 1629 #endif 1630 } 1631 1632 return 0; 1633 1634 out_unlock: 1635 1636 kvm_for_each_vcpu(j, vcpu, kvm) { 1637 if (i == j) 1638 break; 1639 1640 #ifdef CONFIG_PROVE_LOCKING 1641 if (j) 1642 mutex_acquire(&vcpu->mutex.dep_map, role, 0, _THIS_IP_); 1643 #endif 1644 1645 mutex_unlock(&vcpu->mutex); 1646 } 1647 return -EINTR; 1648 } 1649 1650 static void sev_unlock_vcpus_for_migration(struct kvm *kvm) 1651 { 1652 struct kvm_vcpu *vcpu; 1653 unsigned long i; 1654 bool first = true; 1655 1656 kvm_for_each_vcpu(i, vcpu, kvm) { 1657 if (first) 1658 first = false; 1659 else 1660 mutex_acquire(&vcpu->mutex.dep_map, 1661 SEV_NR_MIGRATION_ROLES, 0, _THIS_IP_); 1662 1663 mutex_unlock(&vcpu->mutex); 1664 } 1665 } 1666 1667 static void sev_migrate_from(struct kvm *dst_kvm, struct kvm *src_kvm) 1668 { 1669 struct kvm_sev_info *dst = &to_kvm_svm(dst_kvm)->sev_info; 1670 struct kvm_sev_info *src = &to_kvm_svm(src_kvm)->sev_info; 1671 struct kvm_vcpu *dst_vcpu, *src_vcpu; 1672 struct vcpu_svm *dst_svm, *src_svm; 1673 struct kvm_sev_info *mirror; 1674 unsigned long i; 1675 1676 dst->active = true; 1677 dst->asid = src->asid; 1678 dst->handle = src->handle; 1679 dst->pages_locked = src->pages_locked; 1680 dst->enc_context_owner = src->enc_context_owner; 1681 dst->es_active = src->es_active; 1682 1683 src->asid = 0; 1684 src->active = false; 1685 src->handle = 0; 1686 src->pages_locked = 0; 1687 src->enc_context_owner = NULL; 1688 src->es_active = false; 1689 1690 list_cut_before(&dst->regions_list, &src->regions_list, &src->regions_list); 1691 1692 /* 1693 * If this VM has mirrors, "transfer" each mirror's refcount of the 1694 * source to the destination (this KVM). The caller holds a reference 1695 * to the source, so there's no danger of use-after-free. 1696 */ 1697 list_cut_before(&dst->mirror_vms, &src->mirror_vms, &src->mirror_vms); 1698 list_for_each_entry(mirror, &dst->mirror_vms, mirror_entry) { 1699 kvm_get_kvm(dst_kvm); 1700 kvm_put_kvm(src_kvm); 1701 mirror->enc_context_owner = dst_kvm; 1702 } 1703 1704 /* 1705 * If this VM is a mirror, remove the old mirror from the owners list 1706 * and add the new mirror to the list. 1707 */ 1708 if (is_mirroring_enc_context(dst_kvm)) { 1709 struct kvm_sev_info *owner_sev_info = 1710 &to_kvm_svm(dst->enc_context_owner)->sev_info; 1711 1712 list_del(&src->mirror_entry); 1713 list_add_tail(&dst->mirror_entry, &owner_sev_info->mirror_vms); 1714 } 1715 1716 kvm_for_each_vcpu(i, dst_vcpu, dst_kvm) { 1717 dst_svm = to_svm(dst_vcpu); 1718 1719 sev_init_vmcb(dst_svm); 1720 1721 if (!dst->es_active) 1722 continue; 1723 1724 /* 1725 * Note, the source is not required to have the same number of 1726 * vCPUs as the destination when migrating a vanilla SEV VM. 1727 */ 1728 src_vcpu = kvm_get_vcpu(dst_kvm, i); 1729 src_svm = to_svm(src_vcpu); 1730 1731 /* 1732 * Transfer VMSA and GHCB state to the destination. Nullify and 1733 * clear source fields as appropriate, the state now belongs to 1734 * the destination. 1735 */ 1736 memcpy(&dst_svm->sev_es, &src_svm->sev_es, sizeof(src_svm->sev_es)); 1737 dst_svm->vmcb->control.ghcb_gpa = src_svm->vmcb->control.ghcb_gpa; 1738 dst_svm->vmcb->control.vmsa_pa = src_svm->vmcb->control.vmsa_pa; 1739 dst_vcpu->arch.guest_state_protected = true; 1740 1741 memset(&src_svm->sev_es, 0, sizeof(src_svm->sev_es)); 1742 src_svm->vmcb->control.ghcb_gpa = INVALID_PAGE; 1743 src_svm->vmcb->control.vmsa_pa = INVALID_PAGE; 1744 src_vcpu->arch.guest_state_protected = false; 1745 } 1746 } 1747 1748 static int sev_check_source_vcpus(struct kvm *dst, struct kvm *src) 1749 { 1750 struct kvm_vcpu *src_vcpu; 1751 unsigned long i; 1752 1753 if (!sev_es_guest(src)) 1754 return 0; 1755 1756 if (atomic_read(&src->online_vcpus) != atomic_read(&dst->online_vcpus)) 1757 return -EINVAL; 1758 1759 kvm_for_each_vcpu(i, src_vcpu, src) { 1760 if (!src_vcpu->arch.guest_state_protected) 1761 return -EINVAL; 1762 } 1763 1764 return 0; 1765 } 1766 1767 int sev_vm_move_enc_context_from(struct kvm *kvm, unsigned int source_fd) 1768 { 1769 struct kvm_sev_info *dst_sev = &to_kvm_svm(kvm)->sev_info; 1770 struct kvm_sev_info *src_sev, *cg_cleanup_sev; 1771 struct file *source_kvm_file; 1772 struct kvm *source_kvm; 1773 bool charged = false; 1774 int ret; 1775 1776 source_kvm_file = fget(source_fd); 1777 if (!file_is_kvm(source_kvm_file)) { 1778 ret = -EBADF; 1779 goto out_fput; 1780 } 1781 1782 source_kvm = source_kvm_file->private_data; 1783 ret = sev_lock_two_vms(kvm, source_kvm); 1784 if (ret) 1785 goto out_fput; 1786 1787 if (sev_guest(kvm) || !sev_guest(source_kvm)) { 1788 ret = -EINVAL; 1789 goto out_unlock; 1790 } 1791 1792 src_sev = &to_kvm_svm(source_kvm)->sev_info; 1793 1794 dst_sev->misc_cg = get_current_misc_cg(); 1795 cg_cleanup_sev = dst_sev; 1796 if (dst_sev->misc_cg != src_sev->misc_cg) { 1797 ret = sev_misc_cg_try_charge(dst_sev); 1798 if (ret) 1799 goto out_dst_cgroup; 1800 charged = true; 1801 } 1802 1803 ret = sev_lock_vcpus_for_migration(kvm, SEV_MIGRATION_SOURCE); 1804 if (ret) 1805 goto out_dst_cgroup; 1806 ret = sev_lock_vcpus_for_migration(source_kvm, SEV_MIGRATION_TARGET); 1807 if (ret) 1808 goto out_dst_vcpu; 1809 1810 ret = sev_check_source_vcpus(kvm, source_kvm); 1811 if (ret) 1812 goto out_source_vcpu; 1813 1814 sev_migrate_from(kvm, source_kvm); 1815 kvm_vm_dead(source_kvm); 1816 cg_cleanup_sev = src_sev; 1817 ret = 0; 1818 1819 out_source_vcpu: 1820 sev_unlock_vcpus_for_migration(source_kvm); 1821 out_dst_vcpu: 1822 sev_unlock_vcpus_for_migration(kvm); 1823 out_dst_cgroup: 1824 /* Operates on the source on success, on the destination on failure. */ 1825 if (charged) 1826 sev_misc_cg_uncharge(cg_cleanup_sev); 1827 put_misc_cg(cg_cleanup_sev->misc_cg); 1828 cg_cleanup_sev->misc_cg = NULL; 1829 out_unlock: 1830 sev_unlock_two_vms(kvm, source_kvm); 1831 out_fput: 1832 if (source_kvm_file) 1833 fput(source_kvm_file); 1834 return ret; 1835 } 1836 1837 int sev_mem_enc_ioctl(struct kvm *kvm, void __user *argp) 1838 { 1839 struct kvm_sev_cmd sev_cmd; 1840 int r; 1841 1842 if (!sev_enabled) 1843 return -ENOTTY; 1844 1845 if (!argp) 1846 return 0; 1847 1848 if (copy_from_user(&sev_cmd, argp, sizeof(struct kvm_sev_cmd))) 1849 return -EFAULT; 1850 1851 mutex_lock(&kvm->lock); 1852 1853 /* Only the enc_context_owner handles some memory enc operations. */ 1854 if (is_mirroring_enc_context(kvm) && 1855 !is_cmd_allowed_from_mirror(sev_cmd.id)) { 1856 r = -EINVAL; 1857 goto out; 1858 } 1859 1860 switch (sev_cmd.id) { 1861 case KVM_SEV_ES_INIT: 1862 if (!sev_es_enabled) { 1863 r = -ENOTTY; 1864 goto out; 1865 } 1866 fallthrough; 1867 case KVM_SEV_INIT: 1868 r = sev_guest_init(kvm, &sev_cmd); 1869 break; 1870 case KVM_SEV_LAUNCH_START: 1871 r = sev_launch_start(kvm, &sev_cmd); 1872 break; 1873 case KVM_SEV_LAUNCH_UPDATE_DATA: 1874 r = sev_launch_update_data(kvm, &sev_cmd); 1875 break; 1876 case KVM_SEV_LAUNCH_UPDATE_VMSA: 1877 r = sev_launch_update_vmsa(kvm, &sev_cmd); 1878 break; 1879 case KVM_SEV_LAUNCH_MEASURE: 1880 r = sev_launch_measure(kvm, &sev_cmd); 1881 break; 1882 case KVM_SEV_LAUNCH_FINISH: 1883 r = sev_launch_finish(kvm, &sev_cmd); 1884 break; 1885 case KVM_SEV_GUEST_STATUS: 1886 r = sev_guest_status(kvm, &sev_cmd); 1887 break; 1888 case KVM_SEV_DBG_DECRYPT: 1889 r = sev_dbg_crypt(kvm, &sev_cmd, true); 1890 break; 1891 case KVM_SEV_DBG_ENCRYPT: 1892 r = sev_dbg_crypt(kvm, &sev_cmd, false); 1893 break; 1894 case KVM_SEV_LAUNCH_SECRET: 1895 r = sev_launch_secret(kvm, &sev_cmd); 1896 break; 1897 case KVM_SEV_GET_ATTESTATION_REPORT: 1898 r = sev_get_attestation_report(kvm, &sev_cmd); 1899 break; 1900 case KVM_SEV_SEND_START: 1901 r = sev_send_start(kvm, &sev_cmd); 1902 break; 1903 case KVM_SEV_SEND_UPDATE_DATA: 1904 r = sev_send_update_data(kvm, &sev_cmd); 1905 break; 1906 case KVM_SEV_SEND_FINISH: 1907 r = sev_send_finish(kvm, &sev_cmd); 1908 break; 1909 case KVM_SEV_SEND_CANCEL: 1910 r = sev_send_cancel(kvm, &sev_cmd); 1911 break; 1912 case KVM_SEV_RECEIVE_START: 1913 r = sev_receive_start(kvm, &sev_cmd); 1914 break; 1915 case KVM_SEV_RECEIVE_UPDATE_DATA: 1916 r = sev_receive_update_data(kvm, &sev_cmd); 1917 break; 1918 case KVM_SEV_RECEIVE_FINISH: 1919 r = sev_receive_finish(kvm, &sev_cmd); 1920 break; 1921 default: 1922 r = -EINVAL; 1923 goto out; 1924 } 1925 1926 if (copy_to_user(argp, &sev_cmd, sizeof(struct kvm_sev_cmd))) 1927 r = -EFAULT; 1928 1929 out: 1930 mutex_unlock(&kvm->lock); 1931 return r; 1932 } 1933 1934 int sev_mem_enc_register_region(struct kvm *kvm, 1935 struct kvm_enc_region *range) 1936 { 1937 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 1938 struct enc_region *region; 1939 int ret = 0; 1940 1941 if (!sev_guest(kvm)) 1942 return -ENOTTY; 1943 1944 /* If kvm is mirroring encryption context it isn't responsible for it */ 1945 if (is_mirroring_enc_context(kvm)) 1946 return -EINVAL; 1947 1948 if (range->addr > ULONG_MAX || range->size > ULONG_MAX) 1949 return -EINVAL; 1950 1951 region = kzalloc(sizeof(*region), GFP_KERNEL_ACCOUNT); 1952 if (!region) 1953 return -ENOMEM; 1954 1955 mutex_lock(&kvm->lock); 1956 region->pages = sev_pin_memory(kvm, range->addr, range->size, ®ion->npages, 1); 1957 if (IS_ERR(region->pages)) { 1958 ret = PTR_ERR(region->pages); 1959 mutex_unlock(&kvm->lock); 1960 goto e_free; 1961 } 1962 1963 region->uaddr = range->addr; 1964 region->size = range->size; 1965 1966 list_add_tail(®ion->list, &sev->regions_list); 1967 mutex_unlock(&kvm->lock); 1968 1969 /* 1970 * The guest may change the memory encryption attribute from C=0 -> C=1 1971 * or vice versa for this memory range. Lets make sure caches are 1972 * flushed to ensure that guest data gets written into memory with 1973 * correct C-bit. 1974 */ 1975 sev_clflush_pages(region->pages, region->npages); 1976 1977 return ret; 1978 1979 e_free: 1980 kfree(region); 1981 return ret; 1982 } 1983 1984 static struct enc_region * 1985 find_enc_region(struct kvm *kvm, struct kvm_enc_region *range) 1986 { 1987 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 1988 struct list_head *head = &sev->regions_list; 1989 struct enc_region *i; 1990 1991 list_for_each_entry(i, head, list) { 1992 if (i->uaddr == range->addr && 1993 i->size == range->size) 1994 return i; 1995 } 1996 1997 return NULL; 1998 } 1999 2000 static void __unregister_enc_region_locked(struct kvm *kvm, 2001 struct enc_region *region) 2002 { 2003 sev_unpin_memory(kvm, region->pages, region->npages); 2004 list_del(®ion->list); 2005 kfree(region); 2006 } 2007 2008 int sev_mem_enc_unregister_region(struct kvm *kvm, 2009 struct kvm_enc_region *range) 2010 { 2011 struct enc_region *region; 2012 int ret; 2013 2014 /* If kvm is mirroring encryption context it isn't responsible for it */ 2015 if (is_mirroring_enc_context(kvm)) 2016 return -EINVAL; 2017 2018 mutex_lock(&kvm->lock); 2019 2020 if (!sev_guest(kvm)) { 2021 ret = -ENOTTY; 2022 goto failed; 2023 } 2024 2025 region = find_enc_region(kvm, range); 2026 if (!region) { 2027 ret = -EINVAL; 2028 goto failed; 2029 } 2030 2031 /* 2032 * Ensure that all guest tagged cache entries are flushed before 2033 * releasing the pages back to the system for use. CLFLUSH will 2034 * not do this, so issue a WBINVD. 2035 */ 2036 wbinvd_on_all_cpus(); 2037 2038 __unregister_enc_region_locked(kvm, region); 2039 2040 mutex_unlock(&kvm->lock); 2041 return 0; 2042 2043 failed: 2044 mutex_unlock(&kvm->lock); 2045 return ret; 2046 } 2047 2048 int sev_vm_copy_enc_context_from(struct kvm *kvm, unsigned int source_fd) 2049 { 2050 struct file *source_kvm_file; 2051 struct kvm *source_kvm; 2052 struct kvm_sev_info *source_sev, *mirror_sev; 2053 int ret; 2054 2055 source_kvm_file = fget(source_fd); 2056 if (!file_is_kvm(source_kvm_file)) { 2057 ret = -EBADF; 2058 goto e_source_fput; 2059 } 2060 2061 source_kvm = source_kvm_file->private_data; 2062 ret = sev_lock_two_vms(kvm, source_kvm); 2063 if (ret) 2064 goto e_source_fput; 2065 2066 /* 2067 * Mirrors of mirrors should work, but let's not get silly. Also 2068 * disallow out-of-band SEV/SEV-ES init if the target is already an 2069 * SEV guest, or if vCPUs have been created. KVM relies on vCPUs being 2070 * created after SEV/SEV-ES initialization, e.g. to init intercepts. 2071 */ 2072 if (sev_guest(kvm) || !sev_guest(source_kvm) || 2073 is_mirroring_enc_context(source_kvm) || kvm->created_vcpus) { 2074 ret = -EINVAL; 2075 goto e_unlock; 2076 } 2077 2078 /* 2079 * The mirror kvm holds an enc_context_owner ref so its asid can't 2080 * disappear until we're done with it 2081 */ 2082 source_sev = &to_kvm_svm(source_kvm)->sev_info; 2083 kvm_get_kvm(source_kvm); 2084 mirror_sev = &to_kvm_svm(kvm)->sev_info; 2085 list_add_tail(&mirror_sev->mirror_entry, &source_sev->mirror_vms); 2086 2087 /* Set enc_context_owner and copy its encryption context over */ 2088 mirror_sev->enc_context_owner = source_kvm; 2089 mirror_sev->active = true; 2090 mirror_sev->asid = source_sev->asid; 2091 mirror_sev->fd = source_sev->fd; 2092 mirror_sev->es_active = source_sev->es_active; 2093 mirror_sev->handle = source_sev->handle; 2094 INIT_LIST_HEAD(&mirror_sev->regions_list); 2095 INIT_LIST_HEAD(&mirror_sev->mirror_vms); 2096 ret = 0; 2097 2098 /* 2099 * Do not copy ap_jump_table. Since the mirror does not share the same 2100 * KVM contexts as the original, and they may have different 2101 * memory-views. 2102 */ 2103 2104 e_unlock: 2105 sev_unlock_two_vms(kvm, source_kvm); 2106 e_source_fput: 2107 if (source_kvm_file) 2108 fput(source_kvm_file); 2109 return ret; 2110 } 2111 2112 void sev_vm_destroy(struct kvm *kvm) 2113 { 2114 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 2115 struct list_head *head = &sev->regions_list; 2116 struct list_head *pos, *q; 2117 2118 if (!sev_guest(kvm)) 2119 return; 2120 2121 WARN_ON(!list_empty(&sev->mirror_vms)); 2122 2123 /* If this is a mirror_kvm release the enc_context_owner and skip sev cleanup */ 2124 if (is_mirroring_enc_context(kvm)) { 2125 struct kvm *owner_kvm = sev->enc_context_owner; 2126 2127 mutex_lock(&owner_kvm->lock); 2128 list_del(&sev->mirror_entry); 2129 mutex_unlock(&owner_kvm->lock); 2130 kvm_put_kvm(owner_kvm); 2131 return; 2132 } 2133 2134 /* 2135 * Ensure that all guest tagged cache entries are flushed before 2136 * releasing the pages back to the system for use. CLFLUSH will 2137 * not do this, so issue a WBINVD. 2138 */ 2139 wbinvd_on_all_cpus(); 2140 2141 /* 2142 * if userspace was terminated before unregistering the memory regions 2143 * then lets unpin all the registered memory. 2144 */ 2145 if (!list_empty(head)) { 2146 list_for_each_safe(pos, q, head) { 2147 __unregister_enc_region_locked(kvm, 2148 list_entry(pos, struct enc_region, list)); 2149 cond_resched(); 2150 } 2151 } 2152 2153 sev_unbind_asid(kvm, sev->handle); 2154 sev_asid_free(sev); 2155 } 2156 2157 void __init sev_set_cpu_caps(void) 2158 { 2159 if (!sev_enabled) 2160 kvm_cpu_cap_clear(X86_FEATURE_SEV); 2161 if (!sev_es_enabled) 2162 kvm_cpu_cap_clear(X86_FEATURE_SEV_ES); 2163 } 2164 2165 void __init sev_hardware_setup(void) 2166 { 2167 #ifdef CONFIG_KVM_AMD_SEV 2168 unsigned int eax, ebx, ecx, edx, sev_asid_count, sev_es_asid_count; 2169 bool sev_es_supported = false; 2170 bool sev_supported = false; 2171 2172 if (!sev_enabled || !npt_enabled) 2173 goto out; 2174 2175 /* 2176 * SEV must obviously be supported in hardware. Sanity check that the 2177 * CPU supports decode assists, which is mandatory for SEV guests to 2178 * support instruction emulation. 2179 */ 2180 if (!boot_cpu_has(X86_FEATURE_SEV) || 2181 WARN_ON_ONCE(!boot_cpu_has(X86_FEATURE_DECODEASSISTS))) 2182 goto out; 2183 2184 /* Retrieve SEV CPUID information */ 2185 cpuid(0x8000001f, &eax, &ebx, &ecx, &edx); 2186 2187 /* Set encryption bit location for SEV-ES guests */ 2188 sev_enc_bit = ebx & 0x3f; 2189 2190 /* Maximum number of encrypted guests supported simultaneously */ 2191 max_sev_asid = ecx; 2192 if (!max_sev_asid) 2193 goto out; 2194 2195 /* Minimum ASID value that should be used for SEV guest */ 2196 min_sev_asid = edx; 2197 sev_me_mask = 1UL << (ebx & 0x3f); 2198 2199 /* 2200 * Initialize SEV ASID bitmaps. Allocate space for ASID 0 in the bitmap, 2201 * even though it's never used, so that the bitmap is indexed by the 2202 * actual ASID. 2203 */ 2204 nr_asids = max_sev_asid + 1; 2205 sev_asid_bitmap = bitmap_zalloc(nr_asids, GFP_KERNEL); 2206 if (!sev_asid_bitmap) 2207 goto out; 2208 2209 sev_reclaim_asid_bitmap = bitmap_zalloc(nr_asids, GFP_KERNEL); 2210 if (!sev_reclaim_asid_bitmap) { 2211 bitmap_free(sev_asid_bitmap); 2212 sev_asid_bitmap = NULL; 2213 goto out; 2214 } 2215 2216 sev_asid_count = max_sev_asid - min_sev_asid + 1; 2217 if (misc_cg_set_capacity(MISC_CG_RES_SEV, sev_asid_count)) 2218 goto out; 2219 2220 pr_info("SEV supported: %u ASIDs\n", sev_asid_count); 2221 sev_supported = true; 2222 2223 /* SEV-ES support requested? */ 2224 if (!sev_es_enabled) 2225 goto out; 2226 2227 /* 2228 * SEV-ES requires MMIO caching as KVM doesn't have access to the guest 2229 * instruction stream, i.e. can't emulate in response to a #NPF and 2230 * instead relies on #NPF(RSVD) being reflected into the guest as #VC 2231 * (the guest can then do a #VMGEXIT to request MMIO emulation). 2232 */ 2233 if (!enable_mmio_caching) 2234 goto out; 2235 2236 /* Does the CPU support SEV-ES? */ 2237 if (!boot_cpu_has(X86_FEATURE_SEV_ES)) 2238 goto out; 2239 2240 /* Has the system been allocated ASIDs for SEV-ES? */ 2241 if (min_sev_asid == 1) 2242 goto out; 2243 2244 sev_es_asid_count = min_sev_asid - 1; 2245 if (misc_cg_set_capacity(MISC_CG_RES_SEV_ES, sev_es_asid_count)) 2246 goto out; 2247 2248 pr_info("SEV-ES supported: %u ASIDs\n", sev_es_asid_count); 2249 sev_es_supported = true; 2250 2251 out: 2252 sev_enabled = sev_supported; 2253 sev_es_enabled = sev_es_supported; 2254 #endif 2255 } 2256 2257 void sev_hardware_unsetup(void) 2258 { 2259 if (!sev_enabled) 2260 return; 2261 2262 /* No need to take sev_bitmap_lock, all VMs have been destroyed. */ 2263 sev_flush_asids(1, max_sev_asid); 2264 2265 bitmap_free(sev_asid_bitmap); 2266 bitmap_free(sev_reclaim_asid_bitmap); 2267 2268 misc_cg_set_capacity(MISC_CG_RES_SEV, 0); 2269 misc_cg_set_capacity(MISC_CG_RES_SEV_ES, 0); 2270 } 2271 2272 int sev_cpu_init(struct svm_cpu_data *sd) 2273 { 2274 if (!sev_enabled) 2275 return 0; 2276 2277 sd->sev_vmcbs = kcalloc(nr_asids, sizeof(void *), GFP_KERNEL); 2278 if (!sd->sev_vmcbs) 2279 return -ENOMEM; 2280 2281 return 0; 2282 } 2283 2284 /* 2285 * Pages used by hardware to hold guest encrypted state must be flushed before 2286 * returning them to the system. 2287 */ 2288 static void sev_flush_encrypted_page(struct kvm_vcpu *vcpu, void *va) 2289 { 2290 int asid = to_kvm_svm(vcpu->kvm)->sev_info.asid; 2291 2292 /* 2293 * Note! The address must be a kernel address, as regular page walk 2294 * checks are performed by VM_PAGE_FLUSH, i.e. operating on a user 2295 * address is non-deterministic and unsafe. This function deliberately 2296 * takes a pointer to deter passing in a user address. 2297 */ 2298 unsigned long addr = (unsigned long)va; 2299 2300 /* 2301 * If CPU enforced cache coherency for encrypted mappings of the 2302 * same physical page is supported, use CLFLUSHOPT instead. NOTE: cache 2303 * flush is still needed in order to work properly with DMA devices. 2304 */ 2305 if (boot_cpu_has(X86_FEATURE_SME_COHERENT)) { 2306 clflush_cache_range(va, PAGE_SIZE); 2307 return; 2308 } 2309 2310 /* 2311 * VM Page Flush takes a host virtual address and a guest ASID. Fall 2312 * back to WBINVD if this faults so as not to make any problems worse 2313 * by leaving stale encrypted data in the cache. 2314 */ 2315 if (WARN_ON_ONCE(wrmsrl_safe(MSR_AMD64_VM_PAGE_FLUSH, addr | asid))) 2316 goto do_wbinvd; 2317 2318 return; 2319 2320 do_wbinvd: 2321 wbinvd_on_all_cpus(); 2322 } 2323 2324 void sev_guest_memory_reclaimed(struct kvm *kvm) 2325 { 2326 if (!sev_guest(kvm)) 2327 return; 2328 2329 wbinvd_on_all_cpus(); 2330 } 2331 2332 void sev_free_vcpu(struct kvm_vcpu *vcpu) 2333 { 2334 struct vcpu_svm *svm; 2335 2336 if (!sev_es_guest(vcpu->kvm)) 2337 return; 2338 2339 svm = to_svm(vcpu); 2340 2341 if (vcpu->arch.guest_state_protected) 2342 sev_flush_encrypted_page(vcpu, svm->sev_es.vmsa); 2343 2344 __free_page(virt_to_page(svm->sev_es.vmsa)); 2345 2346 if (svm->sev_es.ghcb_sa_free) 2347 kvfree(svm->sev_es.ghcb_sa); 2348 } 2349 2350 static void dump_ghcb(struct vcpu_svm *svm) 2351 { 2352 struct ghcb *ghcb = svm->sev_es.ghcb; 2353 unsigned int nbits; 2354 2355 /* Re-use the dump_invalid_vmcb module parameter */ 2356 if (!dump_invalid_vmcb) { 2357 pr_warn_ratelimited("set kvm_amd.dump_invalid_vmcb=1 to dump internal KVM state.\n"); 2358 return; 2359 } 2360 2361 nbits = sizeof(ghcb->save.valid_bitmap) * 8; 2362 2363 pr_err("GHCB (GPA=%016llx):\n", svm->vmcb->control.ghcb_gpa); 2364 pr_err("%-20s%016llx is_valid: %u\n", "sw_exit_code", 2365 ghcb->save.sw_exit_code, ghcb_sw_exit_code_is_valid(ghcb)); 2366 pr_err("%-20s%016llx is_valid: %u\n", "sw_exit_info_1", 2367 ghcb->save.sw_exit_info_1, ghcb_sw_exit_info_1_is_valid(ghcb)); 2368 pr_err("%-20s%016llx is_valid: %u\n", "sw_exit_info_2", 2369 ghcb->save.sw_exit_info_2, ghcb_sw_exit_info_2_is_valid(ghcb)); 2370 pr_err("%-20s%016llx is_valid: %u\n", "sw_scratch", 2371 ghcb->save.sw_scratch, ghcb_sw_scratch_is_valid(ghcb)); 2372 pr_err("%-20s%*pb\n", "valid_bitmap", nbits, ghcb->save.valid_bitmap); 2373 } 2374 2375 static void sev_es_sync_to_ghcb(struct vcpu_svm *svm) 2376 { 2377 struct kvm_vcpu *vcpu = &svm->vcpu; 2378 struct ghcb *ghcb = svm->sev_es.ghcb; 2379 2380 /* 2381 * The GHCB protocol so far allows for the following data 2382 * to be returned: 2383 * GPRs RAX, RBX, RCX, RDX 2384 * 2385 * Copy their values, even if they may not have been written during the 2386 * VM-Exit. It's the guest's responsibility to not consume random data. 2387 */ 2388 ghcb_set_rax(ghcb, vcpu->arch.regs[VCPU_REGS_RAX]); 2389 ghcb_set_rbx(ghcb, vcpu->arch.regs[VCPU_REGS_RBX]); 2390 ghcb_set_rcx(ghcb, vcpu->arch.regs[VCPU_REGS_RCX]); 2391 ghcb_set_rdx(ghcb, vcpu->arch.regs[VCPU_REGS_RDX]); 2392 } 2393 2394 static void sev_es_sync_from_ghcb(struct vcpu_svm *svm) 2395 { 2396 struct vmcb_control_area *control = &svm->vmcb->control; 2397 struct kvm_vcpu *vcpu = &svm->vcpu; 2398 struct ghcb *ghcb = svm->sev_es.ghcb; 2399 u64 exit_code; 2400 2401 /* 2402 * The GHCB protocol so far allows for the following data 2403 * to be supplied: 2404 * GPRs RAX, RBX, RCX, RDX 2405 * XCR0 2406 * CPL 2407 * 2408 * VMMCALL allows the guest to provide extra registers. KVM also 2409 * expects RSI for hypercalls, so include that, too. 2410 * 2411 * Copy their values to the appropriate location if supplied. 2412 */ 2413 memset(vcpu->arch.regs, 0, sizeof(vcpu->arch.regs)); 2414 2415 vcpu->arch.regs[VCPU_REGS_RAX] = ghcb_get_rax_if_valid(ghcb); 2416 vcpu->arch.regs[VCPU_REGS_RBX] = ghcb_get_rbx_if_valid(ghcb); 2417 vcpu->arch.regs[VCPU_REGS_RCX] = ghcb_get_rcx_if_valid(ghcb); 2418 vcpu->arch.regs[VCPU_REGS_RDX] = ghcb_get_rdx_if_valid(ghcb); 2419 vcpu->arch.regs[VCPU_REGS_RSI] = ghcb_get_rsi_if_valid(ghcb); 2420 2421 svm->vmcb->save.cpl = ghcb_get_cpl_if_valid(ghcb); 2422 2423 if (ghcb_xcr0_is_valid(ghcb)) { 2424 vcpu->arch.xcr0 = ghcb_get_xcr0(ghcb); 2425 kvm_update_cpuid_runtime(vcpu); 2426 } 2427 2428 /* Copy the GHCB exit information into the VMCB fields */ 2429 exit_code = ghcb_get_sw_exit_code(ghcb); 2430 control->exit_code = lower_32_bits(exit_code); 2431 control->exit_code_hi = upper_32_bits(exit_code); 2432 control->exit_info_1 = ghcb_get_sw_exit_info_1(ghcb); 2433 control->exit_info_2 = ghcb_get_sw_exit_info_2(ghcb); 2434 2435 /* Clear the valid entries fields */ 2436 memset(ghcb->save.valid_bitmap, 0, sizeof(ghcb->save.valid_bitmap)); 2437 } 2438 2439 static int sev_es_validate_vmgexit(struct vcpu_svm *svm) 2440 { 2441 struct kvm_vcpu *vcpu; 2442 struct ghcb *ghcb; 2443 u64 exit_code; 2444 u64 reason; 2445 2446 ghcb = svm->sev_es.ghcb; 2447 2448 /* 2449 * Retrieve the exit code now even though it may not be marked valid 2450 * as it could help with debugging. 2451 */ 2452 exit_code = ghcb_get_sw_exit_code(ghcb); 2453 2454 /* Only GHCB Usage code 0 is supported */ 2455 if (ghcb->ghcb_usage) { 2456 reason = GHCB_ERR_INVALID_USAGE; 2457 goto vmgexit_err; 2458 } 2459 2460 reason = GHCB_ERR_MISSING_INPUT; 2461 2462 if (!ghcb_sw_exit_code_is_valid(ghcb) || 2463 !ghcb_sw_exit_info_1_is_valid(ghcb) || 2464 !ghcb_sw_exit_info_2_is_valid(ghcb)) 2465 goto vmgexit_err; 2466 2467 switch (ghcb_get_sw_exit_code(ghcb)) { 2468 case SVM_EXIT_READ_DR7: 2469 break; 2470 case SVM_EXIT_WRITE_DR7: 2471 if (!ghcb_rax_is_valid(ghcb)) 2472 goto vmgexit_err; 2473 break; 2474 case SVM_EXIT_RDTSC: 2475 break; 2476 case SVM_EXIT_RDPMC: 2477 if (!ghcb_rcx_is_valid(ghcb)) 2478 goto vmgexit_err; 2479 break; 2480 case SVM_EXIT_CPUID: 2481 if (!ghcb_rax_is_valid(ghcb) || 2482 !ghcb_rcx_is_valid(ghcb)) 2483 goto vmgexit_err; 2484 if (ghcb_get_rax(ghcb) == 0xd) 2485 if (!ghcb_xcr0_is_valid(ghcb)) 2486 goto vmgexit_err; 2487 break; 2488 case SVM_EXIT_INVD: 2489 break; 2490 case SVM_EXIT_IOIO: 2491 if (ghcb_get_sw_exit_info_1(ghcb) & SVM_IOIO_STR_MASK) { 2492 if (!ghcb_sw_scratch_is_valid(ghcb)) 2493 goto vmgexit_err; 2494 } else { 2495 if (!(ghcb_get_sw_exit_info_1(ghcb) & SVM_IOIO_TYPE_MASK)) 2496 if (!ghcb_rax_is_valid(ghcb)) 2497 goto vmgexit_err; 2498 } 2499 break; 2500 case SVM_EXIT_MSR: 2501 if (!ghcb_rcx_is_valid(ghcb)) 2502 goto vmgexit_err; 2503 if (ghcb_get_sw_exit_info_1(ghcb)) { 2504 if (!ghcb_rax_is_valid(ghcb) || 2505 !ghcb_rdx_is_valid(ghcb)) 2506 goto vmgexit_err; 2507 } 2508 break; 2509 case SVM_EXIT_VMMCALL: 2510 if (!ghcb_rax_is_valid(ghcb) || 2511 !ghcb_cpl_is_valid(ghcb)) 2512 goto vmgexit_err; 2513 break; 2514 case SVM_EXIT_RDTSCP: 2515 break; 2516 case SVM_EXIT_WBINVD: 2517 break; 2518 case SVM_EXIT_MONITOR: 2519 if (!ghcb_rax_is_valid(ghcb) || 2520 !ghcb_rcx_is_valid(ghcb) || 2521 !ghcb_rdx_is_valid(ghcb)) 2522 goto vmgexit_err; 2523 break; 2524 case SVM_EXIT_MWAIT: 2525 if (!ghcb_rax_is_valid(ghcb) || 2526 !ghcb_rcx_is_valid(ghcb)) 2527 goto vmgexit_err; 2528 break; 2529 case SVM_VMGEXIT_MMIO_READ: 2530 case SVM_VMGEXIT_MMIO_WRITE: 2531 if (!ghcb_sw_scratch_is_valid(ghcb)) 2532 goto vmgexit_err; 2533 break; 2534 case SVM_VMGEXIT_NMI_COMPLETE: 2535 case SVM_VMGEXIT_AP_HLT_LOOP: 2536 case SVM_VMGEXIT_AP_JUMP_TABLE: 2537 case SVM_VMGEXIT_UNSUPPORTED_EVENT: 2538 break; 2539 default: 2540 reason = GHCB_ERR_INVALID_EVENT; 2541 goto vmgexit_err; 2542 } 2543 2544 return 0; 2545 2546 vmgexit_err: 2547 vcpu = &svm->vcpu; 2548 2549 if (reason == GHCB_ERR_INVALID_USAGE) { 2550 vcpu_unimpl(vcpu, "vmgexit: ghcb usage %#x is not valid\n", 2551 ghcb->ghcb_usage); 2552 } else if (reason == GHCB_ERR_INVALID_EVENT) { 2553 vcpu_unimpl(vcpu, "vmgexit: exit code %#llx is not valid\n", 2554 exit_code); 2555 } else { 2556 vcpu_unimpl(vcpu, "vmgexit: exit code %#llx input is not valid\n", 2557 exit_code); 2558 dump_ghcb(svm); 2559 } 2560 2561 /* Clear the valid entries fields */ 2562 memset(ghcb->save.valid_bitmap, 0, sizeof(ghcb->save.valid_bitmap)); 2563 2564 ghcb_set_sw_exit_info_1(ghcb, 2); 2565 ghcb_set_sw_exit_info_2(ghcb, reason); 2566 2567 /* Resume the guest to "return" the error code. */ 2568 return 1; 2569 } 2570 2571 void sev_es_unmap_ghcb(struct vcpu_svm *svm) 2572 { 2573 if (!svm->sev_es.ghcb) 2574 return; 2575 2576 if (svm->sev_es.ghcb_sa_free) { 2577 /* 2578 * The scratch area lives outside the GHCB, so there is a 2579 * buffer that, depending on the operation performed, may 2580 * need to be synced, then freed. 2581 */ 2582 if (svm->sev_es.ghcb_sa_sync) { 2583 kvm_write_guest(svm->vcpu.kvm, 2584 ghcb_get_sw_scratch(svm->sev_es.ghcb), 2585 svm->sev_es.ghcb_sa, 2586 svm->sev_es.ghcb_sa_len); 2587 svm->sev_es.ghcb_sa_sync = false; 2588 } 2589 2590 kvfree(svm->sev_es.ghcb_sa); 2591 svm->sev_es.ghcb_sa = NULL; 2592 svm->sev_es.ghcb_sa_free = false; 2593 } 2594 2595 trace_kvm_vmgexit_exit(svm->vcpu.vcpu_id, svm->sev_es.ghcb); 2596 2597 sev_es_sync_to_ghcb(svm); 2598 2599 kvm_vcpu_unmap(&svm->vcpu, &svm->sev_es.ghcb_map, true); 2600 svm->sev_es.ghcb = NULL; 2601 } 2602 2603 void pre_sev_run(struct vcpu_svm *svm, int cpu) 2604 { 2605 struct svm_cpu_data *sd = per_cpu_ptr(&svm_data, cpu); 2606 int asid = sev_get_asid(svm->vcpu.kvm); 2607 2608 /* Assign the asid allocated with this SEV guest */ 2609 svm->asid = asid; 2610 2611 /* 2612 * Flush guest TLB: 2613 * 2614 * 1) when different VMCB for the same ASID is to be run on the same host CPU. 2615 * 2) or this VMCB was executed on different host CPU in previous VMRUNs. 2616 */ 2617 if (sd->sev_vmcbs[asid] == svm->vmcb && 2618 svm->vcpu.arch.last_vmentry_cpu == cpu) 2619 return; 2620 2621 sd->sev_vmcbs[asid] = svm->vmcb; 2622 svm->vmcb->control.tlb_ctl = TLB_CONTROL_FLUSH_ASID; 2623 vmcb_mark_dirty(svm->vmcb, VMCB_ASID); 2624 } 2625 2626 #define GHCB_SCRATCH_AREA_LIMIT (16ULL * PAGE_SIZE) 2627 static int setup_vmgexit_scratch(struct vcpu_svm *svm, bool sync, u64 len) 2628 { 2629 struct vmcb_control_area *control = &svm->vmcb->control; 2630 struct ghcb *ghcb = svm->sev_es.ghcb; 2631 u64 ghcb_scratch_beg, ghcb_scratch_end; 2632 u64 scratch_gpa_beg, scratch_gpa_end; 2633 void *scratch_va; 2634 2635 scratch_gpa_beg = ghcb_get_sw_scratch(ghcb); 2636 if (!scratch_gpa_beg) { 2637 pr_err("vmgexit: scratch gpa not provided\n"); 2638 goto e_scratch; 2639 } 2640 2641 scratch_gpa_end = scratch_gpa_beg + len; 2642 if (scratch_gpa_end < scratch_gpa_beg) { 2643 pr_err("vmgexit: scratch length (%#llx) not valid for scratch address (%#llx)\n", 2644 len, scratch_gpa_beg); 2645 goto e_scratch; 2646 } 2647 2648 if ((scratch_gpa_beg & PAGE_MASK) == control->ghcb_gpa) { 2649 /* Scratch area begins within GHCB */ 2650 ghcb_scratch_beg = control->ghcb_gpa + 2651 offsetof(struct ghcb, shared_buffer); 2652 ghcb_scratch_end = control->ghcb_gpa + 2653 offsetof(struct ghcb, reserved_0xff0); 2654 2655 /* 2656 * If the scratch area begins within the GHCB, it must be 2657 * completely contained in the GHCB shared buffer area. 2658 */ 2659 if (scratch_gpa_beg < ghcb_scratch_beg || 2660 scratch_gpa_end > ghcb_scratch_end) { 2661 pr_err("vmgexit: scratch area is outside of GHCB shared buffer area (%#llx - %#llx)\n", 2662 scratch_gpa_beg, scratch_gpa_end); 2663 goto e_scratch; 2664 } 2665 2666 scratch_va = (void *)svm->sev_es.ghcb; 2667 scratch_va += (scratch_gpa_beg - control->ghcb_gpa); 2668 } else { 2669 /* 2670 * The guest memory must be read into a kernel buffer, so 2671 * limit the size 2672 */ 2673 if (len > GHCB_SCRATCH_AREA_LIMIT) { 2674 pr_err("vmgexit: scratch area exceeds KVM limits (%#llx requested, %#llx limit)\n", 2675 len, GHCB_SCRATCH_AREA_LIMIT); 2676 goto e_scratch; 2677 } 2678 scratch_va = kvzalloc(len, GFP_KERNEL_ACCOUNT); 2679 if (!scratch_va) 2680 return -ENOMEM; 2681 2682 if (kvm_read_guest(svm->vcpu.kvm, scratch_gpa_beg, scratch_va, len)) { 2683 /* Unable to copy scratch area from guest */ 2684 pr_err("vmgexit: kvm_read_guest for scratch area failed\n"); 2685 2686 kvfree(scratch_va); 2687 return -EFAULT; 2688 } 2689 2690 /* 2691 * The scratch area is outside the GHCB. The operation will 2692 * dictate whether the buffer needs to be synced before running 2693 * the vCPU next time (i.e. a read was requested so the data 2694 * must be written back to the guest memory). 2695 */ 2696 svm->sev_es.ghcb_sa_sync = sync; 2697 svm->sev_es.ghcb_sa_free = true; 2698 } 2699 2700 svm->sev_es.ghcb_sa = scratch_va; 2701 svm->sev_es.ghcb_sa_len = len; 2702 2703 return 0; 2704 2705 e_scratch: 2706 ghcb_set_sw_exit_info_1(ghcb, 2); 2707 ghcb_set_sw_exit_info_2(ghcb, GHCB_ERR_INVALID_SCRATCH_AREA); 2708 2709 return 1; 2710 } 2711 2712 static void set_ghcb_msr_bits(struct vcpu_svm *svm, u64 value, u64 mask, 2713 unsigned int pos) 2714 { 2715 svm->vmcb->control.ghcb_gpa &= ~(mask << pos); 2716 svm->vmcb->control.ghcb_gpa |= (value & mask) << pos; 2717 } 2718 2719 static u64 get_ghcb_msr_bits(struct vcpu_svm *svm, u64 mask, unsigned int pos) 2720 { 2721 return (svm->vmcb->control.ghcb_gpa >> pos) & mask; 2722 } 2723 2724 static void set_ghcb_msr(struct vcpu_svm *svm, u64 value) 2725 { 2726 svm->vmcb->control.ghcb_gpa = value; 2727 } 2728 2729 static int sev_handle_vmgexit_msr_protocol(struct vcpu_svm *svm) 2730 { 2731 struct vmcb_control_area *control = &svm->vmcb->control; 2732 struct kvm_vcpu *vcpu = &svm->vcpu; 2733 u64 ghcb_info; 2734 int ret = 1; 2735 2736 ghcb_info = control->ghcb_gpa & GHCB_MSR_INFO_MASK; 2737 2738 trace_kvm_vmgexit_msr_protocol_enter(svm->vcpu.vcpu_id, 2739 control->ghcb_gpa); 2740 2741 switch (ghcb_info) { 2742 case GHCB_MSR_SEV_INFO_REQ: 2743 set_ghcb_msr(svm, GHCB_MSR_SEV_INFO(GHCB_VERSION_MAX, 2744 GHCB_VERSION_MIN, 2745 sev_enc_bit)); 2746 break; 2747 case GHCB_MSR_CPUID_REQ: { 2748 u64 cpuid_fn, cpuid_reg, cpuid_value; 2749 2750 cpuid_fn = get_ghcb_msr_bits(svm, 2751 GHCB_MSR_CPUID_FUNC_MASK, 2752 GHCB_MSR_CPUID_FUNC_POS); 2753 2754 /* Initialize the registers needed by the CPUID intercept */ 2755 vcpu->arch.regs[VCPU_REGS_RAX] = cpuid_fn; 2756 vcpu->arch.regs[VCPU_REGS_RCX] = 0; 2757 2758 ret = svm_invoke_exit_handler(vcpu, SVM_EXIT_CPUID); 2759 if (!ret) { 2760 /* Error, keep GHCB MSR value as-is */ 2761 break; 2762 } 2763 2764 cpuid_reg = get_ghcb_msr_bits(svm, 2765 GHCB_MSR_CPUID_REG_MASK, 2766 GHCB_MSR_CPUID_REG_POS); 2767 if (cpuid_reg == 0) 2768 cpuid_value = vcpu->arch.regs[VCPU_REGS_RAX]; 2769 else if (cpuid_reg == 1) 2770 cpuid_value = vcpu->arch.regs[VCPU_REGS_RBX]; 2771 else if (cpuid_reg == 2) 2772 cpuid_value = vcpu->arch.regs[VCPU_REGS_RCX]; 2773 else 2774 cpuid_value = vcpu->arch.regs[VCPU_REGS_RDX]; 2775 2776 set_ghcb_msr_bits(svm, cpuid_value, 2777 GHCB_MSR_CPUID_VALUE_MASK, 2778 GHCB_MSR_CPUID_VALUE_POS); 2779 2780 set_ghcb_msr_bits(svm, GHCB_MSR_CPUID_RESP, 2781 GHCB_MSR_INFO_MASK, 2782 GHCB_MSR_INFO_POS); 2783 break; 2784 } 2785 case GHCB_MSR_TERM_REQ: { 2786 u64 reason_set, reason_code; 2787 2788 reason_set = get_ghcb_msr_bits(svm, 2789 GHCB_MSR_TERM_REASON_SET_MASK, 2790 GHCB_MSR_TERM_REASON_SET_POS); 2791 reason_code = get_ghcb_msr_bits(svm, 2792 GHCB_MSR_TERM_REASON_MASK, 2793 GHCB_MSR_TERM_REASON_POS); 2794 pr_info("SEV-ES guest requested termination: %#llx:%#llx\n", 2795 reason_set, reason_code); 2796 2797 vcpu->run->exit_reason = KVM_EXIT_SYSTEM_EVENT; 2798 vcpu->run->system_event.type = KVM_SYSTEM_EVENT_SEV_TERM; 2799 vcpu->run->system_event.ndata = 1; 2800 vcpu->run->system_event.data[0] = control->ghcb_gpa; 2801 2802 return 0; 2803 } 2804 default: 2805 /* Error, keep GHCB MSR value as-is */ 2806 break; 2807 } 2808 2809 trace_kvm_vmgexit_msr_protocol_exit(svm->vcpu.vcpu_id, 2810 control->ghcb_gpa, ret); 2811 2812 return ret; 2813 } 2814 2815 int sev_handle_vmgexit(struct kvm_vcpu *vcpu) 2816 { 2817 struct vcpu_svm *svm = to_svm(vcpu); 2818 struct vmcb_control_area *control = &svm->vmcb->control; 2819 u64 ghcb_gpa, exit_code; 2820 struct ghcb *ghcb; 2821 int ret; 2822 2823 /* Validate the GHCB */ 2824 ghcb_gpa = control->ghcb_gpa; 2825 if (ghcb_gpa & GHCB_MSR_INFO_MASK) 2826 return sev_handle_vmgexit_msr_protocol(svm); 2827 2828 if (!ghcb_gpa) { 2829 vcpu_unimpl(vcpu, "vmgexit: GHCB gpa is not set\n"); 2830 2831 /* Without a GHCB, just return right back to the guest */ 2832 return 1; 2833 } 2834 2835 if (kvm_vcpu_map(vcpu, ghcb_gpa >> PAGE_SHIFT, &svm->sev_es.ghcb_map)) { 2836 /* Unable to map GHCB from guest */ 2837 vcpu_unimpl(vcpu, "vmgexit: error mapping GHCB [%#llx] from guest\n", 2838 ghcb_gpa); 2839 2840 /* Without a GHCB, just return right back to the guest */ 2841 return 1; 2842 } 2843 2844 svm->sev_es.ghcb = svm->sev_es.ghcb_map.hva; 2845 ghcb = svm->sev_es.ghcb_map.hva; 2846 2847 trace_kvm_vmgexit_enter(vcpu->vcpu_id, ghcb); 2848 2849 exit_code = ghcb_get_sw_exit_code(ghcb); 2850 2851 ret = sev_es_validate_vmgexit(svm); 2852 if (ret) 2853 return ret; 2854 2855 sev_es_sync_from_ghcb(svm); 2856 ghcb_set_sw_exit_info_1(ghcb, 0); 2857 ghcb_set_sw_exit_info_2(ghcb, 0); 2858 2859 switch (exit_code) { 2860 case SVM_VMGEXIT_MMIO_READ: 2861 ret = setup_vmgexit_scratch(svm, true, control->exit_info_2); 2862 if (ret) 2863 break; 2864 2865 ret = kvm_sev_es_mmio_read(vcpu, 2866 control->exit_info_1, 2867 control->exit_info_2, 2868 svm->sev_es.ghcb_sa); 2869 break; 2870 case SVM_VMGEXIT_MMIO_WRITE: 2871 ret = setup_vmgexit_scratch(svm, false, control->exit_info_2); 2872 if (ret) 2873 break; 2874 2875 ret = kvm_sev_es_mmio_write(vcpu, 2876 control->exit_info_1, 2877 control->exit_info_2, 2878 svm->sev_es.ghcb_sa); 2879 break; 2880 case SVM_VMGEXIT_NMI_COMPLETE: 2881 ret = svm_invoke_exit_handler(vcpu, SVM_EXIT_IRET); 2882 break; 2883 case SVM_VMGEXIT_AP_HLT_LOOP: 2884 ret = kvm_emulate_ap_reset_hold(vcpu); 2885 break; 2886 case SVM_VMGEXIT_AP_JUMP_TABLE: { 2887 struct kvm_sev_info *sev = &to_kvm_svm(vcpu->kvm)->sev_info; 2888 2889 switch (control->exit_info_1) { 2890 case 0: 2891 /* Set AP jump table address */ 2892 sev->ap_jump_table = control->exit_info_2; 2893 break; 2894 case 1: 2895 /* Get AP jump table address */ 2896 ghcb_set_sw_exit_info_2(ghcb, sev->ap_jump_table); 2897 break; 2898 default: 2899 pr_err("svm: vmgexit: unsupported AP jump table request - exit_info_1=%#llx\n", 2900 control->exit_info_1); 2901 ghcb_set_sw_exit_info_1(ghcb, 2); 2902 ghcb_set_sw_exit_info_2(ghcb, GHCB_ERR_INVALID_INPUT); 2903 } 2904 2905 ret = 1; 2906 break; 2907 } 2908 case SVM_VMGEXIT_UNSUPPORTED_EVENT: 2909 vcpu_unimpl(vcpu, 2910 "vmgexit: unsupported event - exit_info_1=%#llx, exit_info_2=%#llx\n", 2911 control->exit_info_1, control->exit_info_2); 2912 ret = -EINVAL; 2913 break; 2914 default: 2915 ret = svm_invoke_exit_handler(vcpu, exit_code); 2916 } 2917 2918 return ret; 2919 } 2920 2921 int sev_es_string_io(struct vcpu_svm *svm, int size, unsigned int port, int in) 2922 { 2923 int count; 2924 int bytes; 2925 int r; 2926 2927 if (svm->vmcb->control.exit_info_2 > INT_MAX) 2928 return -EINVAL; 2929 2930 count = svm->vmcb->control.exit_info_2; 2931 if (unlikely(check_mul_overflow(count, size, &bytes))) 2932 return -EINVAL; 2933 2934 r = setup_vmgexit_scratch(svm, in, bytes); 2935 if (r) 2936 return r; 2937 2938 return kvm_sev_es_string_io(&svm->vcpu, size, port, svm->sev_es.ghcb_sa, 2939 count, in); 2940 } 2941 2942 static void sev_es_init_vmcb(struct vcpu_svm *svm) 2943 { 2944 struct kvm_vcpu *vcpu = &svm->vcpu; 2945 2946 svm->vmcb->control.nested_ctl |= SVM_NESTED_CTL_SEV_ES_ENABLE; 2947 svm->vmcb->control.virt_ext |= LBR_CTL_ENABLE_MASK; 2948 2949 /* 2950 * An SEV-ES guest requires a VMSA area that is a separate from the 2951 * VMCB page. Do not include the encryption mask on the VMSA physical 2952 * address since hardware will access it using the guest key. 2953 */ 2954 svm->vmcb->control.vmsa_pa = __pa(svm->sev_es.vmsa); 2955 2956 /* Can't intercept CR register access, HV can't modify CR registers */ 2957 svm_clr_intercept(svm, INTERCEPT_CR0_READ); 2958 svm_clr_intercept(svm, INTERCEPT_CR4_READ); 2959 svm_clr_intercept(svm, INTERCEPT_CR8_READ); 2960 svm_clr_intercept(svm, INTERCEPT_CR0_WRITE); 2961 svm_clr_intercept(svm, INTERCEPT_CR4_WRITE); 2962 svm_clr_intercept(svm, INTERCEPT_CR8_WRITE); 2963 2964 svm_clr_intercept(svm, INTERCEPT_SELECTIVE_CR0); 2965 2966 /* Track EFER/CR register changes */ 2967 svm_set_intercept(svm, TRAP_EFER_WRITE); 2968 svm_set_intercept(svm, TRAP_CR0_WRITE); 2969 svm_set_intercept(svm, TRAP_CR4_WRITE); 2970 svm_set_intercept(svm, TRAP_CR8_WRITE); 2971 2972 /* No support for enable_vmware_backdoor */ 2973 clr_exception_intercept(svm, GP_VECTOR); 2974 2975 /* Can't intercept XSETBV, HV can't modify XCR0 directly */ 2976 svm_clr_intercept(svm, INTERCEPT_XSETBV); 2977 2978 /* Clear intercepts on selected MSRs */ 2979 set_msr_interception(vcpu, svm->msrpm, MSR_EFER, 1, 1); 2980 set_msr_interception(vcpu, svm->msrpm, MSR_IA32_CR_PAT, 1, 1); 2981 set_msr_interception(vcpu, svm->msrpm, MSR_IA32_LASTBRANCHFROMIP, 1, 1); 2982 set_msr_interception(vcpu, svm->msrpm, MSR_IA32_LASTBRANCHTOIP, 1, 1); 2983 set_msr_interception(vcpu, svm->msrpm, MSR_IA32_LASTINTFROMIP, 1, 1); 2984 set_msr_interception(vcpu, svm->msrpm, MSR_IA32_LASTINTTOIP, 1, 1); 2985 2986 if (boot_cpu_has(X86_FEATURE_V_TSC_AUX) && 2987 (guest_cpuid_has(&svm->vcpu, X86_FEATURE_RDTSCP) || 2988 guest_cpuid_has(&svm->vcpu, X86_FEATURE_RDPID))) { 2989 set_msr_interception(vcpu, svm->msrpm, MSR_TSC_AUX, 1, 1); 2990 if (guest_cpuid_has(&svm->vcpu, X86_FEATURE_RDTSCP)) 2991 svm_clr_intercept(svm, INTERCEPT_RDTSCP); 2992 } 2993 } 2994 2995 void sev_init_vmcb(struct vcpu_svm *svm) 2996 { 2997 svm->vmcb->control.nested_ctl |= SVM_NESTED_CTL_SEV_ENABLE; 2998 clr_exception_intercept(svm, UD_VECTOR); 2999 3000 if (sev_es_guest(svm->vcpu.kvm)) 3001 sev_es_init_vmcb(svm); 3002 } 3003 3004 void sev_es_vcpu_reset(struct vcpu_svm *svm) 3005 { 3006 /* 3007 * Set the GHCB MSR value as per the GHCB specification when emulating 3008 * vCPU RESET for an SEV-ES guest. 3009 */ 3010 set_ghcb_msr(svm, GHCB_MSR_SEV_INFO(GHCB_VERSION_MAX, 3011 GHCB_VERSION_MIN, 3012 sev_enc_bit)); 3013 } 3014 3015 void sev_es_prepare_switch_to_guest(struct sev_es_save_area *hostsa) 3016 { 3017 /* 3018 * As an SEV-ES guest, hardware will restore the host state on VMEXIT, 3019 * of which one step is to perform a VMLOAD. KVM performs the 3020 * corresponding VMSAVE in svm_prepare_guest_switch for both 3021 * traditional and SEV-ES guests. 3022 */ 3023 3024 /* XCR0 is restored on VMEXIT, save the current host value */ 3025 hostsa->xcr0 = xgetbv(XCR_XFEATURE_ENABLED_MASK); 3026 3027 /* PKRU is restored on VMEXIT, save the current host value */ 3028 hostsa->pkru = read_pkru(); 3029 3030 /* MSR_IA32_XSS is restored on VMEXIT, save the currnet host value */ 3031 hostsa->xss = host_xss; 3032 } 3033 3034 void sev_vcpu_deliver_sipi_vector(struct kvm_vcpu *vcpu, u8 vector) 3035 { 3036 struct vcpu_svm *svm = to_svm(vcpu); 3037 3038 /* First SIPI: Use the values as initially set by the VMM */ 3039 if (!svm->sev_es.received_first_sipi) { 3040 svm->sev_es.received_first_sipi = true; 3041 return; 3042 } 3043 3044 /* 3045 * Subsequent SIPI: Return from an AP Reset Hold VMGEXIT, where 3046 * the guest will set the CS and RIP. Set SW_EXIT_INFO_2 to a 3047 * non-zero value. 3048 */ 3049 if (!svm->sev_es.ghcb) 3050 return; 3051 3052 ghcb_set_sw_exit_info_2(svm->sev_es.ghcb, 1); 3053 } 3054