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 fd f = fdget(source_fd); 1772 struct kvm *source_kvm; 1773 bool charged = false; 1774 int ret; 1775 1776 if (!f.file) 1777 return -EBADF; 1778 1779 if (!file_is_kvm(f.file)) { 1780 ret = -EBADF; 1781 goto out_fput; 1782 } 1783 1784 source_kvm = f.file->private_data; 1785 ret = sev_lock_two_vms(kvm, source_kvm); 1786 if (ret) 1787 goto out_fput; 1788 1789 if (sev_guest(kvm) || !sev_guest(source_kvm)) { 1790 ret = -EINVAL; 1791 goto out_unlock; 1792 } 1793 1794 src_sev = &to_kvm_svm(source_kvm)->sev_info; 1795 1796 dst_sev->misc_cg = get_current_misc_cg(); 1797 cg_cleanup_sev = dst_sev; 1798 if (dst_sev->misc_cg != src_sev->misc_cg) { 1799 ret = sev_misc_cg_try_charge(dst_sev); 1800 if (ret) 1801 goto out_dst_cgroup; 1802 charged = true; 1803 } 1804 1805 ret = sev_lock_vcpus_for_migration(kvm, SEV_MIGRATION_SOURCE); 1806 if (ret) 1807 goto out_dst_cgroup; 1808 ret = sev_lock_vcpus_for_migration(source_kvm, SEV_MIGRATION_TARGET); 1809 if (ret) 1810 goto out_dst_vcpu; 1811 1812 ret = sev_check_source_vcpus(kvm, source_kvm); 1813 if (ret) 1814 goto out_source_vcpu; 1815 1816 sev_migrate_from(kvm, source_kvm); 1817 kvm_vm_dead(source_kvm); 1818 cg_cleanup_sev = src_sev; 1819 ret = 0; 1820 1821 out_source_vcpu: 1822 sev_unlock_vcpus_for_migration(source_kvm); 1823 out_dst_vcpu: 1824 sev_unlock_vcpus_for_migration(kvm); 1825 out_dst_cgroup: 1826 /* Operates on the source on success, on the destination on failure. */ 1827 if (charged) 1828 sev_misc_cg_uncharge(cg_cleanup_sev); 1829 put_misc_cg(cg_cleanup_sev->misc_cg); 1830 cg_cleanup_sev->misc_cg = NULL; 1831 out_unlock: 1832 sev_unlock_two_vms(kvm, source_kvm); 1833 out_fput: 1834 fdput(f); 1835 return ret; 1836 } 1837 1838 int sev_mem_enc_ioctl(struct kvm *kvm, void __user *argp) 1839 { 1840 struct kvm_sev_cmd sev_cmd; 1841 int r; 1842 1843 if (!sev_enabled) 1844 return -ENOTTY; 1845 1846 if (!argp) 1847 return 0; 1848 1849 if (copy_from_user(&sev_cmd, argp, sizeof(struct kvm_sev_cmd))) 1850 return -EFAULT; 1851 1852 mutex_lock(&kvm->lock); 1853 1854 /* Only the enc_context_owner handles some memory enc operations. */ 1855 if (is_mirroring_enc_context(kvm) && 1856 !is_cmd_allowed_from_mirror(sev_cmd.id)) { 1857 r = -EINVAL; 1858 goto out; 1859 } 1860 1861 switch (sev_cmd.id) { 1862 case KVM_SEV_ES_INIT: 1863 if (!sev_es_enabled) { 1864 r = -ENOTTY; 1865 goto out; 1866 } 1867 fallthrough; 1868 case KVM_SEV_INIT: 1869 r = sev_guest_init(kvm, &sev_cmd); 1870 break; 1871 case KVM_SEV_LAUNCH_START: 1872 r = sev_launch_start(kvm, &sev_cmd); 1873 break; 1874 case KVM_SEV_LAUNCH_UPDATE_DATA: 1875 r = sev_launch_update_data(kvm, &sev_cmd); 1876 break; 1877 case KVM_SEV_LAUNCH_UPDATE_VMSA: 1878 r = sev_launch_update_vmsa(kvm, &sev_cmd); 1879 break; 1880 case KVM_SEV_LAUNCH_MEASURE: 1881 r = sev_launch_measure(kvm, &sev_cmd); 1882 break; 1883 case KVM_SEV_LAUNCH_FINISH: 1884 r = sev_launch_finish(kvm, &sev_cmd); 1885 break; 1886 case KVM_SEV_GUEST_STATUS: 1887 r = sev_guest_status(kvm, &sev_cmd); 1888 break; 1889 case KVM_SEV_DBG_DECRYPT: 1890 r = sev_dbg_crypt(kvm, &sev_cmd, true); 1891 break; 1892 case KVM_SEV_DBG_ENCRYPT: 1893 r = sev_dbg_crypt(kvm, &sev_cmd, false); 1894 break; 1895 case KVM_SEV_LAUNCH_SECRET: 1896 r = sev_launch_secret(kvm, &sev_cmd); 1897 break; 1898 case KVM_SEV_GET_ATTESTATION_REPORT: 1899 r = sev_get_attestation_report(kvm, &sev_cmd); 1900 break; 1901 case KVM_SEV_SEND_START: 1902 r = sev_send_start(kvm, &sev_cmd); 1903 break; 1904 case KVM_SEV_SEND_UPDATE_DATA: 1905 r = sev_send_update_data(kvm, &sev_cmd); 1906 break; 1907 case KVM_SEV_SEND_FINISH: 1908 r = sev_send_finish(kvm, &sev_cmd); 1909 break; 1910 case KVM_SEV_SEND_CANCEL: 1911 r = sev_send_cancel(kvm, &sev_cmd); 1912 break; 1913 case KVM_SEV_RECEIVE_START: 1914 r = sev_receive_start(kvm, &sev_cmd); 1915 break; 1916 case KVM_SEV_RECEIVE_UPDATE_DATA: 1917 r = sev_receive_update_data(kvm, &sev_cmd); 1918 break; 1919 case KVM_SEV_RECEIVE_FINISH: 1920 r = sev_receive_finish(kvm, &sev_cmd); 1921 break; 1922 default: 1923 r = -EINVAL; 1924 goto out; 1925 } 1926 1927 if (copy_to_user(argp, &sev_cmd, sizeof(struct kvm_sev_cmd))) 1928 r = -EFAULT; 1929 1930 out: 1931 mutex_unlock(&kvm->lock); 1932 return r; 1933 } 1934 1935 int sev_mem_enc_register_region(struct kvm *kvm, 1936 struct kvm_enc_region *range) 1937 { 1938 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 1939 struct enc_region *region; 1940 int ret = 0; 1941 1942 if (!sev_guest(kvm)) 1943 return -ENOTTY; 1944 1945 /* If kvm is mirroring encryption context it isn't responsible for it */ 1946 if (is_mirroring_enc_context(kvm)) 1947 return -EINVAL; 1948 1949 if (range->addr > ULONG_MAX || range->size > ULONG_MAX) 1950 return -EINVAL; 1951 1952 region = kzalloc(sizeof(*region), GFP_KERNEL_ACCOUNT); 1953 if (!region) 1954 return -ENOMEM; 1955 1956 mutex_lock(&kvm->lock); 1957 region->pages = sev_pin_memory(kvm, range->addr, range->size, ®ion->npages, 1); 1958 if (IS_ERR(region->pages)) { 1959 ret = PTR_ERR(region->pages); 1960 mutex_unlock(&kvm->lock); 1961 goto e_free; 1962 } 1963 1964 region->uaddr = range->addr; 1965 region->size = range->size; 1966 1967 list_add_tail(®ion->list, &sev->regions_list); 1968 mutex_unlock(&kvm->lock); 1969 1970 /* 1971 * The guest may change the memory encryption attribute from C=0 -> C=1 1972 * or vice versa for this memory range. Lets make sure caches are 1973 * flushed to ensure that guest data gets written into memory with 1974 * correct C-bit. 1975 */ 1976 sev_clflush_pages(region->pages, region->npages); 1977 1978 return ret; 1979 1980 e_free: 1981 kfree(region); 1982 return ret; 1983 } 1984 1985 static struct enc_region * 1986 find_enc_region(struct kvm *kvm, struct kvm_enc_region *range) 1987 { 1988 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 1989 struct list_head *head = &sev->regions_list; 1990 struct enc_region *i; 1991 1992 list_for_each_entry(i, head, list) { 1993 if (i->uaddr == range->addr && 1994 i->size == range->size) 1995 return i; 1996 } 1997 1998 return NULL; 1999 } 2000 2001 static void __unregister_enc_region_locked(struct kvm *kvm, 2002 struct enc_region *region) 2003 { 2004 sev_unpin_memory(kvm, region->pages, region->npages); 2005 list_del(®ion->list); 2006 kfree(region); 2007 } 2008 2009 int sev_mem_enc_unregister_region(struct kvm *kvm, 2010 struct kvm_enc_region *range) 2011 { 2012 struct enc_region *region; 2013 int ret; 2014 2015 /* If kvm is mirroring encryption context it isn't responsible for it */ 2016 if (is_mirroring_enc_context(kvm)) 2017 return -EINVAL; 2018 2019 mutex_lock(&kvm->lock); 2020 2021 if (!sev_guest(kvm)) { 2022 ret = -ENOTTY; 2023 goto failed; 2024 } 2025 2026 region = find_enc_region(kvm, range); 2027 if (!region) { 2028 ret = -EINVAL; 2029 goto failed; 2030 } 2031 2032 /* 2033 * Ensure that all guest tagged cache entries are flushed before 2034 * releasing the pages back to the system for use. CLFLUSH will 2035 * not do this, so issue a WBINVD. 2036 */ 2037 wbinvd_on_all_cpus(); 2038 2039 __unregister_enc_region_locked(kvm, region); 2040 2041 mutex_unlock(&kvm->lock); 2042 return 0; 2043 2044 failed: 2045 mutex_unlock(&kvm->lock); 2046 return ret; 2047 } 2048 2049 int sev_vm_copy_enc_context_from(struct kvm *kvm, unsigned int source_fd) 2050 { 2051 struct fd f = fdget(source_fd); 2052 struct kvm *source_kvm; 2053 struct kvm_sev_info *source_sev, *mirror_sev; 2054 int ret; 2055 2056 if (!f.file) 2057 return -EBADF; 2058 2059 if (!file_is_kvm(f.file)) { 2060 ret = -EBADF; 2061 goto e_source_fput; 2062 } 2063 2064 source_kvm = f.file->private_data; 2065 ret = sev_lock_two_vms(kvm, source_kvm); 2066 if (ret) 2067 goto e_source_fput; 2068 2069 /* 2070 * Mirrors of mirrors should work, but let's not get silly. Also 2071 * disallow out-of-band SEV/SEV-ES init if the target is already an 2072 * SEV guest, or if vCPUs have been created. KVM relies on vCPUs being 2073 * created after SEV/SEV-ES initialization, e.g. to init intercepts. 2074 */ 2075 if (sev_guest(kvm) || !sev_guest(source_kvm) || 2076 is_mirroring_enc_context(source_kvm) || kvm->created_vcpus) { 2077 ret = -EINVAL; 2078 goto e_unlock; 2079 } 2080 2081 /* 2082 * The mirror kvm holds an enc_context_owner ref so its asid can't 2083 * disappear until we're done with it 2084 */ 2085 source_sev = &to_kvm_svm(source_kvm)->sev_info; 2086 kvm_get_kvm(source_kvm); 2087 mirror_sev = &to_kvm_svm(kvm)->sev_info; 2088 list_add_tail(&mirror_sev->mirror_entry, &source_sev->mirror_vms); 2089 2090 /* Set enc_context_owner and copy its encryption context over */ 2091 mirror_sev->enc_context_owner = source_kvm; 2092 mirror_sev->active = true; 2093 mirror_sev->asid = source_sev->asid; 2094 mirror_sev->fd = source_sev->fd; 2095 mirror_sev->es_active = source_sev->es_active; 2096 mirror_sev->handle = source_sev->handle; 2097 INIT_LIST_HEAD(&mirror_sev->regions_list); 2098 INIT_LIST_HEAD(&mirror_sev->mirror_vms); 2099 ret = 0; 2100 2101 /* 2102 * Do not copy ap_jump_table. Since the mirror does not share the same 2103 * KVM contexts as the original, and they may have different 2104 * memory-views. 2105 */ 2106 2107 e_unlock: 2108 sev_unlock_two_vms(kvm, source_kvm); 2109 e_source_fput: 2110 fdput(f); 2111 return ret; 2112 } 2113 2114 void sev_vm_destroy(struct kvm *kvm) 2115 { 2116 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 2117 struct list_head *head = &sev->regions_list; 2118 struct list_head *pos, *q; 2119 2120 if (!sev_guest(kvm)) 2121 return; 2122 2123 WARN_ON(!list_empty(&sev->mirror_vms)); 2124 2125 /* If this is a mirror_kvm release the enc_context_owner and skip sev cleanup */ 2126 if (is_mirroring_enc_context(kvm)) { 2127 struct kvm *owner_kvm = sev->enc_context_owner; 2128 2129 mutex_lock(&owner_kvm->lock); 2130 list_del(&sev->mirror_entry); 2131 mutex_unlock(&owner_kvm->lock); 2132 kvm_put_kvm(owner_kvm); 2133 return; 2134 } 2135 2136 /* 2137 * Ensure that all guest tagged cache entries are flushed before 2138 * releasing the pages back to the system for use. CLFLUSH will 2139 * not do this, so issue a WBINVD. 2140 */ 2141 wbinvd_on_all_cpus(); 2142 2143 /* 2144 * if userspace was terminated before unregistering the memory regions 2145 * then lets unpin all the registered memory. 2146 */ 2147 if (!list_empty(head)) { 2148 list_for_each_safe(pos, q, head) { 2149 __unregister_enc_region_locked(kvm, 2150 list_entry(pos, struct enc_region, list)); 2151 cond_resched(); 2152 } 2153 } 2154 2155 sev_unbind_asid(kvm, sev->handle); 2156 sev_asid_free(sev); 2157 } 2158 2159 void __init sev_set_cpu_caps(void) 2160 { 2161 if (!sev_enabled) 2162 kvm_cpu_cap_clear(X86_FEATURE_SEV); 2163 if (!sev_es_enabled) 2164 kvm_cpu_cap_clear(X86_FEATURE_SEV_ES); 2165 } 2166 2167 void __init sev_hardware_setup(void) 2168 { 2169 #ifdef CONFIG_KVM_AMD_SEV 2170 unsigned int eax, ebx, ecx, edx, sev_asid_count, sev_es_asid_count; 2171 bool sev_es_supported = false; 2172 bool sev_supported = false; 2173 2174 if (!sev_enabled || !npt_enabled) 2175 goto out; 2176 2177 /* 2178 * SEV must obviously be supported in hardware. Sanity check that the 2179 * CPU supports decode assists, which is mandatory for SEV guests to 2180 * support instruction emulation. 2181 */ 2182 if (!boot_cpu_has(X86_FEATURE_SEV) || 2183 WARN_ON_ONCE(!boot_cpu_has(X86_FEATURE_DECODEASSISTS))) 2184 goto out; 2185 2186 /* Retrieve SEV CPUID information */ 2187 cpuid(0x8000001f, &eax, &ebx, &ecx, &edx); 2188 2189 /* Set encryption bit location for SEV-ES guests */ 2190 sev_enc_bit = ebx & 0x3f; 2191 2192 /* Maximum number of encrypted guests supported simultaneously */ 2193 max_sev_asid = ecx; 2194 if (!max_sev_asid) 2195 goto out; 2196 2197 /* Minimum ASID value that should be used for SEV guest */ 2198 min_sev_asid = edx; 2199 sev_me_mask = 1UL << (ebx & 0x3f); 2200 2201 /* 2202 * Initialize SEV ASID bitmaps. Allocate space for ASID 0 in the bitmap, 2203 * even though it's never used, so that the bitmap is indexed by the 2204 * actual ASID. 2205 */ 2206 nr_asids = max_sev_asid + 1; 2207 sev_asid_bitmap = bitmap_zalloc(nr_asids, GFP_KERNEL); 2208 if (!sev_asid_bitmap) 2209 goto out; 2210 2211 sev_reclaim_asid_bitmap = bitmap_zalloc(nr_asids, GFP_KERNEL); 2212 if (!sev_reclaim_asid_bitmap) { 2213 bitmap_free(sev_asid_bitmap); 2214 sev_asid_bitmap = NULL; 2215 goto out; 2216 } 2217 2218 sev_asid_count = max_sev_asid - min_sev_asid + 1; 2219 WARN_ON_ONCE(misc_cg_set_capacity(MISC_CG_RES_SEV, sev_asid_count)); 2220 sev_supported = true; 2221 2222 /* SEV-ES support requested? */ 2223 if (!sev_es_enabled) 2224 goto out; 2225 2226 /* 2227 * SEV-ES requires MMIO caching as KVM doesn't have access to the guest 2228 * instruction stream, i.e. can't emulate in response to a #NPF and 2229 * instead relies on #NPF(RSVD) being reflected into the guest as #VC 2230 * (the guest can then do a #VMGEXIT to request MMIO emulation). 2231 */ 2232 if (!enable_mmio_caching) 2233 goto out; 2234 2235 /* Does the CPU support SEV-ES? */ 2236 if (!boot_cpu_has(X86_FEATURE_SEV_ES)) 2237 goto out; 2238 2239 /* Has the system been allocated ASIDs for SEV-ES? */ 2240 if (min_sev_asid == 1) 2241 goto out; 2242 2243 sev_es_asid_count = min_sev_asid - 1; 2244 WARN_ON_ONCE(misc_cg_set_capacity(MISC_CG_RES_SEV_ES, sev_es_asid_count)); 2245 sev_es_supported = true; 2246 2247 out: 2248 if (boot_cpu_has(X86_FEATURE_SEV)) 2249 pr_info("SEV %s (ASIDs %u - %u)\n", 2250 sev_supported ? "enabled" : "disabled", 2251 min_sev_asid, max_sev_asid); 2252 if (boot_cpu_has(X86_FEATURE_SEV_ES)) 2253 pr_info("SEV-ES %s (ASIDs %u - %u)\n", 2254 sev_es_supported ? "enabled" : "disabled", 2255 min_sev_asid > 1 ? 1 : 0, min_sev_asid - 1); 2256 2257 sev_enabled = sev_supported; 2258 sev_es_enabled = sev_es_supported; 2259 #endif 2260 } 2261 2262 void sev_hardware_unsetup(void) 2263 { 2264 if (!sev_enabled) 2265 return; 2266 2267 /* No need to take sev_bitmap_lock, all VMs have been destroyed. */ 2268 sev_flush_asids(1, max_sev_asid); 2269 2270 bitmap_free(sev_asid_bitmap); 2271 bitmap_free(sev_reclaim_asid_bitmap); 2272 2273 misc_cg_set_capacity(MISC_CG_RES_SEV, 0); 2274 misc_cg_set_capacity(MISC_CG_RES_SEV_ES, 0); 2275 } 2276 2277 int sev_cpu_init(struct svm_cpu_data *sd) 2278 { 2279 if (!sev_enabled) 2280 return 0; 2281 2282 sd->sev_vmcbs = kcalloc(nr_asids, sizeof(void *), GFP_KERNEL); 2283 if (!sd->sev_vmcbs) 2284 return -ENOMEM; 2285 2286 return 0; 2287 } 2288 2289 /* 2290 * Pages used by hardware to hold guest encrypted state must be flushed before 2291 * returning them to the system. 2292 */ 2293 static void sev_flush_encrypted_page(struct kvm_vcpu *vcpu, void *va) 2294 { 2295 int asid = to_kvm_svm(vcpu->kvm)->sev_info.asid; 2296 2297 /* 2298 * Note! The address must be a kernel address, as regular page walk 2299 * checks are performed by VM_PAGE_FLUSH, i.e. operating on a user 2300 * address is non-deterministic and unsafe. This function deliberately 2301 * takes a pointer to deter passing in a user address. 2302 */ 2303 unsigned long addr = (unsigned long)va; 2304 2305 /* 2306 * If CPU enforced cache coherency for encrypted mappings of the 2307 * same physical page is supported, use CLFLUSHOPT instead. NOTE: cache 2308 * flush is still needed in order to work properly with DMA devices. 2309 */ 2310 if (boot_cpu_has(X86_FEATURE_SME_COHERENT)) { 2311 clflush_cache_range(va, PAGE_SIZE); 2312 return; 2313 } 2314 2315 /* 2316 * VM Page Flush takes a host virtual address and a guest ASID. Fall 2317 * back to WBINVD if this faults so as not to make any problems worse 2318 * by leaving stale encrypted data in the cache. 2319 */ 2320 if (WARN_ON_ONCE(wrmsrl_safe(MSR_AMD64_VM_PAGE_FLUSH, addr | asid))) 2321 goto do_wbinvd; 2322 2323 return; 2324 2325 do_wbinvd: 2326 wbinvd_on_all_cpus(); 2327 } 2328 2329 void sev_guest_memory_reclaimed(struct kvm *kvm) 2330 { 2331 if (!sev_guest(kvm)) 2332 return; 2333 2334 wbinvd_on_all_cpus(); 2335 } 2336 2337 void sev_free_vcpu(struct kvm_vcpu *vcpu) 2338 { 2339 struct vcpu_svm *svm; 2340 2341 if (!sev_es_guest(vcpu->kvm)) 2342 return; 2343 2344 svm = to_svm(vcpu); 2345 2346 if (vcpu->arch.guest_state_protected) 2347 sev_flush_encrypted_page(vcpu, svm->sev_es.vmsa); 2348 2349 __free_page(virt_to_page(svm->sev_es.vmsa)); 2350 2351 if (svm->sev_es.ghcb_sa_free) 2352 kvfree(svm->sev_es.ghcb_sa); 2353 } 2354 2355 static void dump_ghcb(struct vcpu_svm *svm) 2356 { 2357 struct ghcb *ghcb = svm->sev_es.ghcb; 2358 unsigned int nbits; 2359 2360 /* Re-use the dump_invalid_vmcb module parameter */ 2361 if (!dump_invalid_vmcb) { 2362 pr_warn_ratelimited("set kvm_amd.dump_invalid_vmcb=1 to dump internal KVM state.\n"); 2363 return; 2364 } 2365 2366 nbits = sizeof(ghcb->save.valid_bitmap) * 8; 2367 2368 pr_err("GHCB (GPA=%016llx):\n", svm->vmcb->control.ghcb_gpa); 2369 pr_err("%-20s%016llx is_valid: %u\n", "sw_exit_code", 2370 ghcb->save.sw_exit_code, ghcb_sw_exit_code_is_valid(ghcb)); 2371 pr_err("%-20s%016llx is_valid: %u\n", "sw_exit_info_1", 2372 ghcb->save.sw_exit_info_1, ghcb_sw_exit_info_1_is_valid(ghcb)); 2373 pr_err("%-20s%016llx is_valid: %u\n", "sw_exit_info_2", 2374 ghcb->save.sw_exit_info_2, ghcb_sw_exit_info_2_is_valid(ghcb)); 2375 pr_err("%-20s%016llx is_valid: %u\n", "sw_scratch", 2376 ghcb->save.sw_scratch, ghcb_sw_scratch_is_valid(ghcb)); 2377 pr_err("%-20s%*pb\n", "valid_bitmap", nbits, ghcb->save.valid_bitmap); 2378 } 2379 2380 static void sev_es_sync_to_ghcb(struct vcpu_svm *svm) 2381 { 2382 struct kvm_vcpu *vcpu = &svm->vcpu; 2383 struct ghcb *ghcb = svm->sev_es.ghcb; 2384 2385 /* 2386 * The GHCB protocol so far allows for the following data 2387 * to be returned: 2388 * GPRs RAX, RBX, RCX, RDX 2389 * 2390 * Copy their values, even if they may not have been written during the 2391 * VM-Exit. It's the guest's responsibility to not consume random data. 2392 */ 2393 ghcb_set_rax(ghcb, vcpu->arch.regs[VCPU_REGS_RAX]); 2394 ghcb_set_rbx(ghcb, vcpu->arch.regs[VCPU_REGS_RBX]); 2395 ghcb_set_rcx(ghcb, vcpu->arch.regs[VCPU_REGS_RCX]); 2396 ghcb_set_rdx(ghcb, vcpu->arch.regs[VCPU_REGS_RDX]); 2397 } 2398 2399 static void sev_es_sync_from_ghcb(struct vcpu_svm *svm) 2400 { 2401 struct vmcb_control_area *control = &svm->vmcb->control; 2402 struct kvm_vcpu *vcpu = &svm->vcpu; 2403 struct ghcb *ghcb = svm->sev_es.ghcb; 2404 u64 exit_code; 2405 2406 /* 2407 * The GHCB protocol so far allows for the following data 2408 * to be supplied: 2409 * GPRs RAX, RBX, RCX, RDX 2410 * XCR0 2411 * CPL 2412 * 2413 * VMMCALL allows the guest to provide extra registers. KVM also 2414 * expects RSI for hypercalls, so include that, too. 2415 * 2416 * Copy their values to the appropriate location if supplied. 2417 */ 2418 memset(vcpu->arch.regs, 0, sizeof(vcpu->arch.regs)); 2419 2420 BUILD_BUG_ON(sizeof(svm->sev_es.valid_bitmap) != sizeof(ghcb->save.valid_bitmap)); 2421 memcpy(&svm->sev_es.valid_bitmap, &ghcb->save.valid_bitmap, sizeof(ghcb->save.valid_bitmap)); 2422 2423 vcpu->arch.regs[VCPU_REGS_RAX] = kvm_ghcb_get_rax_if_valid(svm, ghcb); 2424 vcpu->arch.regs[VCPU_REGS_RBX] = kvm_ghcb_get_rbx_if_valid(svm, ghcb); 2425 vcpu->arch.regs[VCPU_REGS_RCX] = kvm_ghcb_get_rcx_if_valid(svm, ghcb); 2426 vcpu->arch.regs[VCPU_REGS_RDX] = kvm_ghcb_get_rdx_if_valid(svm, ghcb); 2427 vcpu->arch.regs[VCPU_REGS_RSI] = kvm_ghcb_get_rsi_if_valid(svm, ghcb); 2428 2429 svm->vmcb->save.cpl = kvm_ghcb_get_cpl_if_valid(svm, ghcb); 2430 2431 if (kvm_ghcb_xcr0_is_valid(svm)) { 2432 vcpu->arch.xcr0 = ghcb_get_xcr0(ghcb); 2433 kvm_update_cpuid_runtime(vcpu); 2434 } 2435 2436 /* Copy the GHCB exit information into the VMCB fields */ 2437 exit_code = ghcb_get_sw_exit_code(ghcb); 2438 control->exit_code = lower_32_bits(exit_code); 2439 control->exit_code_hi = upper_32_bits(exit_code); 2440 control->exit_info_1 = ghcb_get_sw_exit_info_1(ghcb); 2441 control->exit_info_2 = ghcb_get_sw_exit_info_2(ghcb); 2442 svm->sev_es.sw_scratch = kvm_ghcb_get_sw_scratch_if_valid(svm, ghcb); 2443 2444 /* Clear the valid entries fields */ 2445 memset(ghcb->save.valid_bitmap, 0, sizeof(ghcb->save.valid_bitmap)); 2446 } 2447 2448 static u64 kvm_ghcb_get_sw_exit_code(struct vmcb_control_area *control) 2449 { 2450 return (((u64)control->exit_code_hi) << 32) | control->exit_code; 2451 } 2452 2453 static int sev_es_validate_vmgexit(struct vcpu_svm *svm) 2454 { 2455 struct vmcb_control_area *control = &svm->vmcb->control; 2456 struct kvm_vcpu *vcpu = &svm->vcpu; 2457 u64 exit_code; 2458 u64 reason; 2459 2460 /* 2461 * Retrieve the exit code now even though it may not be marked valid 2462 * as it could help with debugging. 2463 */ 2464 exit_code = kvm_ghcb_get_sw_exit_code(control); 2465 2466 /* Only GHCB Usage code 0 is supported */ 2467 if (svm->sev_es.ghcb->ghcb_usage) { 2468 reason = GHCB_ERR_INVALID_USAGE; 2469 goto vmgexit_err; 2470 } 2471 2472 reason = GHCB_ERR_MISSING_INPUT; 2473 2474 if (!kvm_ghcb_sw_exit_code_is_valid(svm) || 2475 !kvm_ghcb_sw_exit_info_1_is_valid(svm) || 2476 !kvm_ghcb_sw_exit_info_2_is_valid(svm)) 2477 goto vmgexit_err; 2478 2479 switch (exit_code) { 2480 case SVM_EXIT_READ_DR7: 2481 break; 2482 case SVM_EXIT_WRITE_DR7: 2483 if (!kvm_ghcb_rax_is_valid(svm)) 2484 goto vmgexit_err; 2485 break; 2486 case SVM_EXIT_RDTSC: 2487 break; 2488 case SVM_EXIT_RDPMC: 2489 if (!kvm_ghcb_rcx_is_valid(svm)) 2490 goto vmgexit_err; 2491 break; 2492 case SVM_EXIT_CPUID: 2493 if (!kvm_ghcb_rax_is_valid(svm) || 2494 !kvm_ghcb_rcx_is_valid(svm)) 2495 goto vmgexit_err; 2496 if (vcpu->arch.regs[VCPU_REGS_RAX] == 0xd) 2497 if (!kvm_ghcb_xcr0_is_valid(svm)) 2498 goto vmgexit_err; 2499 break; 2500 case SVM_EXIT_INVD: 2501 break; 2502 case SVM_EXIT_IOIO: 2503 if (control->exit_info_1 & SVM_IOIO_STR_MASK) { 2504 if (!kvm_ghcb_sw_scratch_is_valid(svm)) 2505 goto vmgexit_err; 2506 } else { 2507 if (!(control->exit_info_1 & SVM_IOIO_TYPE_MASK)) 2508 if (!kvm_ghcb_rax_is_valid(svm)) 2509 goto vmgexit_err; 2510 } 2511 break; 2512 case SVM_EXIT_MSR: 2513 if (!kvm_ghcb_rcx_is_valid(svm)) 2514 goto vmgexit_err; 2515 if (control->exit_info_1) { 2516 if (!kvm_ghcb_rax_is_valid(svm) || 2517 !kvm_ghcb_rdx_is_valid(svm)) 2518 goto vmgexit_err; 2519 } 2520 break; 2521 case SVM_EXIT_VMMCALL: 2522 if (!kvm_ghcb_rax_is_valid(svm) || 2523 !kvm_ghcb_cpl_is_valid(svm)) 2524 goto vmgexit_err; 2525 break; 2526 case SVM_EXIT_RDTSCP: 2527 break; 2528 case SVM_EXIT_WBINVD: 2529 break; 2530 case SVM_EXIT_MONITOR: 2531 if (!kvm_ghcb_rax_is_valid(svm) || 2532 !kvm_ghcb_rcx_is_valid(svm) || 2533 !kvm_ghcb_rdx_is_valid(svm)) 2534 goto vmgexit_err; 2535 break; 2536 case SVM_EXIT_MWAIT: 2537 if (!kvm_ghcb_rax_is_valid(svm) || 2538 !kvm_ghcb_rcx_is_valid(svm)) 2539 goto vmgexit_err; 2540 break; 2541 case SVM_VMGEXIT_MMIO_READ: 2542 case SVM_VMGEXIT_MMIO_WRITE: 2543 if (!kvm_ghcb_sw_scratch_is_valid(svm)) 2544 goto vmgexit_err; 2545 break; 2546 case SVM_VMGEXIT_NMI_COMPLETE: 2547 case SVM_VMGEXIT_AP_HLT_LOOP: 2548 case SVM_VMGEXIT_AP_JUMP_TABLE: 2549 case SVM_VMGEXIT_UNSUPPORTED_EVENT: 2550 break; 2551 default: 2552 reason = GHCB_ERR_INVALID_EVENT; 2553 goto vmgexit_err; 2554 } 2555 2556 return 0; 2557 2558 vmgexit_err: 2559 if (reason == GHCB_ERR_INVALID_USAGE) { 2560 vcpu_unimpl(vcpu, "vmgexit: ghcb usage %#x is not valid\n", 2561 svm->sev_es.ghcb->ghcb_usage); 2562 } else if (reason == GHCB_ERR_INVALID_EVENT) { 2563 vcpu_unimpl(vcpu, "vmgexit: exit code %#llx is not valid\n", 2564 exit_code); 2565 } else { 2566 vcpu_unimpl(vcpu, "vmgexit: exit code %#llx input is not valid\n", 2567 exit_code); 2568 dump_ghcb(svm); 2569 } 2570 2571 ghcb_set_sw_exit_info_1(svm->sev_es.ghcb, 2); 2572 ghcb_set_sw_exit_info_2(svm->sev_es.ghcb, reason); 2573 2574 /* Resume the guest to "return" the error code. */ 2575 return 1; 2576 } 2577 2578 void sev_es_unmap_ghcb(struct vcpu_svm *svm) 2579 { 2580 if (!svm->sev_es.ghcb) 2581 return; 2582 2583 if (svm->sev_es.ghcb_sa_free) { 2584 /* 2585 * The scratch area lives outside the GHCB, so there is a 2586 * buffer that, depending on the operation performed, may 2587 * need to be synced, then freed. 2588 */ 2589 if (svm->sev_es.ghcb_sa_sync) { 2590 kvm_write_guest(svm->vcpu.kvm, 2591 svm->sev_es.sw_scratch, 2592 svm->sev_es.ghcb_sa, 2593 svm->sev_es.ghcb_sa_len); 2594 svm->sev_es.ghcb_sa_sync = false; 2595 } 2596 2597 kvfree(svm->sev_es.ghcb_sa); 2598 svm->sev_es.ghcb_sa = NULL; 2599 svm->sev_es.ghcb_sa_free = false; 2600 } 2601 2602 trace_kvm_vmgexit_exit(svm->vcpu.vcpu_id, svm->sev_es.ghcb); 2603 2604 sev_es_sync_to_ghcb(svm); 2605 2606 kvm_vcpu_unmap(&svm->vcpu, &svm->sev_es.ghcb_map, true); 2607 svm->sev_es.ghcb = NULL; 2608 } 2609 2610 void pre_sev_run(struct vcpu_svm *svm, int cpu) 2611 { 2612 struct svm_cpu_data *sd = per_cpu_ptr(&svm_data, cpu); 2613 int asid = sev_get_asid(svm->vcpu.kvm); 2614 2615 /* Assign the asid allocated with this SEV guest */ 2616 svm->asid = asid; 2617 2618 /* 2619 * Flush guest TLB: 2620 * 2621 * 1) when different VMCB for the same ASID is to be run on the same host CPU. 2622 * 2) or this VMCB was executed on different host CPU in previous VMRUNs. 2623 */ 2624 if (sd->sev_vmcbs[asid] == svm->vmcb && 2625 svm->vcpu.arch.last_vmentry_cpu == cpu) 2626 return; 2627 2628 sd->sev_vmcbs[asid] = svm->vmcb; 2629 svm->vmcb->control.tlb_ctl = TLB_CONTROL_FLUSH_ASID; 2630 vmcb_mark_dirty(svm->vmcb, VMCB_ASID); 2631 } 2632 2633 #define GHCB_SCRATCH_AREA_LIMIT (16ULL * PAGE_SIZE) 2634 static int setup_vmgexit_scratch(struct vcpu_svm *svm, bool sync, u64 len) 2635 { 2636 struct vmcb_control_area *control = &svm->vmcb->control; 2637 u64 ghcb_scratch_beg, ghcb_scratch_end; 2638 u64 scratch_gpa_beg, scratch_gpa_end; 2639 void *scratch_va; 2640 2641 scratch_gpa_beg = svm->sev_es.sw_scratch; 2642 if (!scratch_gpa_beg) { 2643 pr_err("vmgexit: scratch gpa not provided\n"); 2644 goto e_scratch; 2645 } 2646 2647 scratch_gpa_end = scratch_gpa_beg + len; 2648 if (scratch_gpa_end < scratch_gpa_beg) { 2649 pr_err("vmgexit: scratch length (%#llx) not valid for scratch address (%#llx)\n", 2650 len, scratch_gpa_beg); 2651 goto e_scratch; 2652 } 2653 2654 if ((scratch_gpa_beg & PAGE_MASK) == control->ghcb_gpa) { 2655 /* Scratch area begins within GHCB */ 2656 ghcb_scratch_beg = control->ghcb_gpa + 2657 offsetof(struct ghcb, shared_buffer); 2658 ghcb_scratch_end = control->ghcb_gpa + 2659 offsetof(struct ghcb, reserved_0xff0); 2660 2661 /* 2662 * If the scratch area begins within the GHCB, it must be 2663 * completely contained in the GHCB shared buffer area. 2664 */ 2665 if (scratch_gpa_beg < ghcb_scratch_beg || 2666 scratch_gpa_end > ghcb_scratch_end) { 2667 pr_err("vmgexit: scratch area is outside of GHCB shared buffer area (%#llx - %#llx)\n", 2668 scratch_gpa_beg, scratch_gpa_end); 2669 goto e_scratch; 2670 } 2671 2672 scratch_va = (void *)svm->sev_es.ghcb; 2673 scratch_va += (scratch_gpa_beg - control->ghcb_gpa); 2674 } else { 2675 /* 2676 * The guest memory must be read into a kernel buffer, so 2677 * limit the size 2678 */ 2679 if (len > GHCB_SCRATCH_AREA_LIMIT) { 2680 pr_err("vmgexit: scratch area exceeds KVM limits (%#llx requested, %#llx limit)\n", 2681 len, GHCB_SCRATCH_AREA_LIMIT); 2682 goto e_scratch; 2683 } 2684 scratch_va = kvzalloc(len, GFP_KERNEL_ACCOUNT); 2685 if (!scratch_va) 2686 return -ENOMEM; 2687 2688 if (kvm_read_guest(svm->vcpu.kvm, scratch_gpa_beg, scratch_va, len)) { 2689 /* Unable to copy scratch area from guest */ 2690 pr_err("vmgexit: kvm_read_guest for scratch area failed\n"); 2691 2692 kvfree(scratch_va); 2693 return -EFAULT; 2694 } 2695 2696 /* 2697 * The scratch area is outside the GHCB. The operation will 2698 * dictate whether the buffer needs to be synced before running 2699 * the vCPU next time (i.e. a read was requested so the data 2700 * must be written back to the guest memory). 2701 */ 2702 svm->sev_es.ghcb_sa_sync = sync; 2703 svm->sev_es.ghcb_sa_free = true; 2704 } 2705 2706 svm->sev_es.ghcb_sa = scratch_va; 2707 svm->sev_es.ghcb_sa_len = len; 2708 2709 return 0; 2710 2711 e_scratch: 2712 ghcb_set_sw_exit_info_1(svm->sev_es.ghcb, 2); 2713 ghcb_set_sw_exit_info_2(svm->sev_es.ghcb, GHCB_ERR_INVALID_SCRATCH_AREA); 2714 2715 return 1; 2716 } 2717 2718 static void set_ghcb_msr_bits(struct vcpu_svm *svm, u64 value, u64 mask, 2719 unsigned int pos) 2720 { 2721 svm->vmcb->control.ghcb_gpa &= ~(mask << pos); 2722 svm->vmcb->control.ghcb_gpa |= (value & mask) << pos; 2723 } 2724 2725 static u64 get_ghcb_msr_bits(struct vcpu_svm *svm, u64 mask, unsigned int pos) 2726 { 2727 return (svm->vmcb->control.ghcb_gpa >> pos) & mask; 2728 } 2729 2730 static void set_ghcb_msr(struct vcpu_svm *svm, u64 value) 2731 { 2732 svm->vmcb->control.ghcb_gpa = value; 2733 } 2734 2735 static int sev_handle_vmgexit_msr_protocol(struct vcpu_svm *svm) 2736 { 2737 struct vmcb_control_area *control = &svm->vmcb->control; 2738 struct kvm_vcpu *vcpu = &svm->vcpu; 2739 u64 ghcb_info; 2740 int ret = 1; 2741 2742 ghcb_info = control->ghcb_gpa & GHCB_MSR_INFO_MASK; 2743 2744 trace_kvm_vmgexit_msr_protocol_enter(svm->vcpu.vcpu_id, 2745 control->ghcb_gpa); 2746 2747 switch (ghcb_info) { 2748 case GHCB_MSR_SEV_INFO_REQ: 2749 set_ghcb_msr(svm, GHCB_MSR_SEV_INFO(GHCB_VERSION_MAX, 2750 GHCB_VERSION_MIN, 2751 sev_enc_bit)); 2752 break; 2753 case GHCB_MSR_CPUID_REQ: { 2754 u64 cpuid_fn, cpuid_reg, cpuid_value; 2755 2756 cpuid_fn = get_ghcb_msr_bits(svm, 2757 GHCB_MSR_CPUID_FUNC_MASK, 2758 GHCB_MSR_CPUID_FUNC_POS); 2759 2760 /* Initialize the registers needed by the CPUID intercept */ 2761 vcpu->arch.regs[VCPU_REGS_RAX] = cpuid_fn; 2762 vcpu->arch.regs[VCPU_REGS_RCX] = 0; 2763 2764 ret = svm_invoke_exit_handler(vcpu, SVM_EXIT_CPUID); 2765 if (!ret) { 2766 /* Error, keep GHCB MSR value as-is */ 2767 break; 2768 } 2769 2770 cpuid_reg = get_ghcb_msr_bits(svm, 2771 GHCB_MSR_CPUID_REG_MASK, 2772 GHCB_MSR_CPUID_REG_POS); 2773 if (cpuid_reg == 0) 2774 cpuid_value = vcpu->arch.regs[VCPU_REGS_RAX]; 2775 else if (cpuid_reg == 1) 2776 cpuid_value = vcpu->arch.regs[VCPU_REGS_RBX]; 2777 else if (cpuid_reg == 2) 2778 cpuid_value = vcpu->arch.regs[VCPU_REGS_RCX]; 2779 else 2780 cpuid_value = vcpu->arch.regs[VCPU_REGS_RDX]; 2781 2782 set_ghcb_msr_bits(svm, cpuid_value, 2783 GHCB_MSR_CPUID_VALUE_MASK, 2784 GHCB_MSR_CPUID_VALUE_POS); 2785 2786 set_ghcb_msr_bits(svm, GHCB_MSR_CPUID_RESP, 2787 GHCB_MSR_INFO_MASK, 2788 GHCB_MSR_INFO_POS); 2789 break; 2790 } 2791 case GHCB_MSR_TERM_REQ: { 2792 u64 reason_set, reason_code; 2793 2794 reason_set = get_ghcb_msr_bits(svm, 2795 GHCB_MSR_TERM_REASON_SET_MASK, 2796 GHCB_MSR_TERM_REASON_SET_POS); 2797 reason_code = get_ghcb_msr_bits(svm, 2798 GHCB_MSR_TERM_REASON_MASK, 2799 GHCB_MSR_TERM_REASON_POS); 2800 pr_info("SEV-ES guest requested termination: %#llx:%#llx\n", 2801 reason_set, reason_code); 2802 2803 vcpu->run->exit_reason = KVM_EXIT_SYSTEM_EVENT; 2804 vcpu->run->system_event.type = KVM_SYSTEM_EVENT_SEV_TERM; 2805 vcpu->run->system_event.ndata = 1; 2806 vcpu->run->system_event.data[0] = control->ghcb_gpa; 2807 2808 return 0; 2809 } 2810 default: 2811 /* Error, keep GHCB MSR value as-is */ 2812 break; 2813 } 2814 2815 trace_kvm_vmgexit_msr_protocol_exit(svm->vcpu.vcpu_id, 2816 control->ghcb_gpa, ret); 2817 2818 return ret; 2819 } 2820 2821 int sev_handle_vmgexit(struct kvm_vcpu *vcpu) 2822 { 2823 struct vcpu_svm *svm = to_svm(vcpu); 2824 struct vmcb_control_area *control = &svm->vmcb->control; 2825 u64 ghcb_gpa, exit_code; 2826 int ret; 2827 2828 /* Validate the GHCB */ 2829 ghcb_gpa = control->ghcb_gpa; 2830 if (ghcb_gpa & GHCB_MSR_INFO_MASK) 2831 return sev_handle_vmgexit_msr_protocol(svm); 2832 2833 if (!ghcb_gpa) { 2834 vcpu_unimpl(vcpu, "vmgexit: GHCB gpa is not set\n"); 2835 2836 /* Without a GHCB, just return right back to the guest */ 2837 return 1; 2838 } 2839 2840 if (kvm_vcpu_map(vcpu, ghcb_gpa >> PAGE_SHIFT, &svm->sev_es.ghcb_map)) { 2841 /* Unable to map GHCB from guest */ 2842 vcpu_unimpl(vcpu, "vmgexit: error mapping GHCB [%#llx] from guest\n", 2843 ghcb_gpa); 2844 2845 /* Without a GHCB, just return right back to the guest */ 2846 return 1; 2847 } 2848 2849 svm->sev_es.ghcb = svm->sev_es.ghcb_map.hva; 2850 2851 trace_kvm_vmgexit_enter(vcpu->vcpu_id, svm->sev_es.ghcb); 2852 2853 sev_es_sync_from_ghcb(svm); 2854 ret = sev_es_validate_vmgexit(svm); 2855 if (ret) 2856 return ret; 2857 2858 ghcb_set_sw_exit_info_1(svm->sev_es.ghcb, 0); 2859 ghcb_set_sw_exit_info_2(svm->sev_es.ghcb, 0); 2860 2861 exit_code = kvm_ghcb_get_sw_exit_code(control); 2862 switch (exit_code) { 2863 case SVM_VMGEXIT_MMIO_READ: 2864 ret = setup_vmgexit_scratch(svm, true, control->exit_info_2); 2865 if (ret) 2866 break; 2867 2868 ret = kvm_sev_es_mmio_read(vcpu, 2869 control->exit_info_1, 2870 control->exit_info_2, 2871 svm->sev_es.ghcb_sa); 2872 break; 2873 case SVM_VMGEXIT_MMIO_WRITE: 2874 ret = setup_vmgexit_scratch(svm, false, control->exit_info_2); 2875 if (ret) 2876 break; 2877 2878 ret = kvm_sev_es_mmio_write(vcpu, 2879 control->exit_info_1, 2880 control->exit_info_2, 2881 svm->sev_es.ghcb_sa); 2882 break; 2883 case SVM_VMGEXIT_NMI_COMPLETE: 2884 ret = svm_invoke_exit_handler(vcpu, SVM_EXIT_IRET); 2885 break; 2886 case SVM_VMGEXIT_AP_HLT_LOOP: 2887 ret = kvm_emulate_ap_reset_hold(vcpu); 2888 break; 2889 case SVM_VMGEXIT_AP_JUMP_TABLE: { 2890 struct kvm_sev_info *sev = &to_kvm_svm(vcpu->kvm)->sev_info; 2891 2892 switch (control->exit_info_1) { 2893 case 0: 2894 /* Set AP jump table address */ 2895 sev->ap_jump_table = control->exit_info_2; 2896 break; 2897 case 1: 2898 /* Get AP jump table address */ 2899 ghcb_set_sw_exit_info_2(svm->sev_es.ghcb, sev->ap_jump_table); 2900 break; 2901 default: 2902 pr_err("svm: vmgexit: unsupported AP jump table request - exit_info_1=%#llx\n", 2903 control->exit_info_1); 2904 ghcb_set_sw_exit_info_1(svm->sev_es.ghcb, 2); 2905 ghcb_set_sw_exit_info_2(svm->sev_es.ghcb, GHCB_ERR_INVALID_INPUT); 2906 } 2907 2908 ret = 1; 2909 break; 2910 } 2911 case SVM_VMGEXIT_UNSUPPORTED_EVENT: 2912 vcpu_unimpl(vcpu, 2913 "vmgexit: unsupported event - exit_info_1=%#llx, exit_info_2=%#llx\n", 2914 control->exit_info_1, control->exit_info_2); 2915 ret = -EINVAL; 2916 break; 2917 default: 2918 ret = svm_invoke_exit_handler(vcpu, exit_code); 2919 } 2920 2921 return ret; 2922 } 2923 2924 int sev_es_string_io(struct vcpu_svm *svm, int size, unsigned int port, int in) 2925 { 2926 int count; 2927 int bytes; 2928 int r; 2929 2930 if (svm->vmcb->control.exit_info_2 > INT_MAX) 2931 return -EINVAL; 2932 2933 count = svm->vmcb->control.exit_info_2; 2934 if (unlikely(check_mul_overflow(count, size, &bytes))) 2935 return -EINVAL; 2936 2937 r = setup_vmgexit_scratch(svm, in, bytes); 2938 if (r) 2939 return r; 2940 2941 return kvm_sev_es_string_io(&svm->vcpu, size, port, svm->sev_es.ghcb_sa, 2942 count, in); 2943 } 2944 2945 static void sev_es_init_vmcb(struct vcpu_svm *svm) 2946 { 2947 struct kvm_vcpu *vcpu = &svm->vcpu; 2948 2949 svm->vmcb->control.nested_ctl |= SVM_NESTED_CTL_SEV_ES_ENABLE; 2950 svm->vmcb->control.virt_ext |= LBR_CTL_ENABLE_MASK; 2951 2952 /* 2953 * An SEV-ES guest requires a VMSA area that is a separate from the 2954 * VMCB page. Do not include the encryption mask on the VMSA physical 2955 * address since hardware will access it using the guest key. 2956 */ 2957 svm->vmcb->control.vmsa_pa = __pa(svm->sev_es.vmsa); 2958 2959 /* Can't intercept CR register access, HV can't modify CR registers */ 2960 svm_clr_intercept(svm, INTERCEPT_CR0_READ); 2961 svm_clr_intercept(svm, INTERCEPT_CR4_READ); 2962 svm_clr_intercept(svm, INTERCEPT_CR8_READ); 2963 svm_clr_intercept(svm, INTERCEPT_CR0_WRITE); 2964 svm_clr_intercept(svm, INTERCEPT_CR4_WRITE); 2965 svm_clr_intercept(svm, INTERCEPT_CR8_WRITE); 2966 2967 svm_clr_intercept(svm, INTERCEPT_SELECTIVE_CR0); 2968 2969 /* Track EFER/CR register changes */ 2970 svm_set_intercept(svm, TRAP_EFER_WRITE); 2971 svm_set_intercept(svm, TRAP_CR0_WRITE); 2972 svm_set_intercept(svm, TRAP_CR4_WRITE); 2973 svm_set_intercept(svm, TRAP_CR8_WRITE); 2974 2975 /* No support for enable_vmware_backdoor */ 2976 clr_exception_intercept(svm, GP_VECTOR); 2977 2978 /* Can't intercept XSETBV, HV can't modify XCR0 directly */ 2979 svm_clr_intercept(svm, INTERCEPT_XSETBV); 2980 2981 /* Clear intercepts on selected MSRs */ 2982 set_msr_interception(vcpu, svm->msrpm, MSR_EFER, 1, 1); 2983 set_msr_interception(vcpu, svm->msrpm, MSR_IA32_CR_PAT, 1, 1); 2984 set_msr_interception(vcpu, svm->msrpm, MSR_IA32_LASTBRANCHFROMIP, 1, 1); 2985 set_msr_interception(vcpu, svm->msrpm, MSR_IA32_LASTBRANCHTOIP, 1, 1); 2986 set_msr_interception(vcpu, svm->msrpm, MSR_IA32_LASTINTFROMIP, 1, 1); 2987 set_msr_interception(vcpu, svm->msrpm, MSR_IA32_LASTINTTOIP, 1, 1); 2988 2989 if (boot_cpu_has(X86_FEATURE_V_TSC_AUX) && 2990 (guest_cpuid_has(&svm->vcpu, X86_FEATURE_RDTSCP) || 2991 guest_cpuid_has(&svm->vcpu, X86_FEATURE_RDPID))) { 2992 set_msr_interception(vcpu, svm->msrpm, MSR_TSC_AUX, 1, 1); 2993 if (guest_cpuid_has(&svm->vcpu, X86_FEATURE_RDTSCP)) 2994 svm_clr_intercept(svm, INTERCEPT_RDTSCP); 2995 } 2996 } 2997 2998 void sev_init_vmcb(struct vcpu_svm *svm) 2999 { 3000 svm->vmcb->control.nested_ctl |= SVM_NESTED_CTL_SEV_ENABLE; 3001 clr_exception_intercept(svm, UD_VECTOR); 3002 3003 if (sev_es_guest(svm->vcpu.kvm)) 3004 sev_es_init_vmcb(svm); 3005 } 3006 3007 void sev_es_vcpu_reset(struct vcpu_svm *svm) 3008 { 3009 /* 3010 * Set the GHCB MSR value as per the GHCB specification when emulating 3011 * vCPU RESET for an SEV-ES guest. 3012 */ 3013 set_ghcb_msr(svm, GHCB_MSR_SEV_INFO(GHCB_VERSION_MAX, 3014 GHCB_VERSION_MIN, 3015 sev_enc_bit)); 3016 } 3017 3018 void sev_es_prepare_switch_to_guest(struct sev_es_save_area *hostsa) 3019 { 3020 /* 3021 * As an SEV-ES guest, hardware will restore the host state on VMEXIT, 3022 * of which one step is to perform a VMLOAD. KVM performs the 3023 * corresponding VMSAVE in svm_prepare_guest_switch for both 3024 * traditional and SEV-ES guests. 3025 */ 3026 3027 /* XCR0 is restored on VMEXIT, save the current host value */ 3028 hostsa->xcr0 = xgetbv(XCR_XFEATURE_ENABLED_MASK); 3029 3030 /* PKRU is restored on VMEXIT, save the current host value */ 3031 hostsa->pkru = read_pkru(); 3032 3033 /* MSR_IA32_XSS is restored on VMEXIT, save the currnet host value */ 3034 hostsa->xss = host_xss; 3035 } 3036 3037 void sev_vcpu_deliver_sipi_vector(struct kvm_vcpu *vcpu, u8 vector) 3038 { 3039 struct vcpu_svm *svm = to_svm(vcpu); 3040 3041 /* First SIPI: Use the values as initially set by the VMM */ 3042 if (!svm->sev_es.received_first_sipi) { 3043 svm->sev_es.received_first_sipi = true; 3044 return; 3045 } 3046 3047 /* 3048 * Subsequent SIPI: Return from an AP Reset Hold VMGEXIT, where 3049 * the guest will set the CS and RIP. Set SW_EXIT_INFO_2 to a 3050 * non-zero value. 3051 */ 3052 if (!svm->sev_es.ghcb) 3053 return; 3054 3055 ghcb_set_sw_exit_info_2(svm->sev_es.ghcb, 1); 3056 } 3057