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-sev.h> 16 #include <linux/pagemap.h> 17 #include <linux/swap.h> 18 #include <linux/misc_cgroup.h> 19 #include <linux/processor.h> 20 #include <linux/trace_events.h> 21 22 #include <asm/pkru.h> 23 #include <asm/trapnr.h> 24 #include <asm/fpu/xcr.h> 25 26 #include "mmu.h" 27 #include "x86.h" 28 #include "svm.h" 29 #include "svm_ops.h" 30 #include "cpuid.h" 31 #include "trace.h" 32 33 #ifndef CONFIG_KVM_AMD_SEV 34 /* 35 * When this config is not defined, SEV feature is not supported and APIs in 36 * this file are not used but this file still gets compiled into the KVM AMD 37 * module. 38 * 39 * We will not have MISC_CG_RES_SEV and MISC_CG_RES_SEV_ES entries in the enum 40 * misc_res_type {} defined in linux/misc_cgroup.h. 41 * 42 * Below macros allow compilation to succeed. 43 */ 44 #define MISC_CG_RES_SEV MISC_CG_RES_TYPES 45 #define MISC_CG_RES_SEV_ES MISC_CG_RES_TYPES 46 #endif 47 48 #ifdef CONFIG_KVM_AMD_SEV 49 /* enable/disable SEV support */ 50 static bool sev_enabled = true; 51 module_param_named(sev, sev_enabled, bool, 0444); 52 53 /* enable/disable SEV-ES support */ 54 static bool sev_es_enabled = true; 55 module_param_named(sev_es, sev_es_enabled, bool, 0444); 56 #else 57 #define sev_enabled false 58 #define sev_es_enabled false 59 #endif /* CONFIG_KVM_AMD_SEV */ 60 61 static u8 sev_enc_bit; 62 static DECLARE_RWSEM(sev_deactivate_lock); 63 static DEFINE_MUTEX(sev_bitmap_lock); 64 unsigned int max_sev_asid; 65 static unsigned int min_sev_asid; 66 static unsigned long sev_me_mask; 67 static unsigned int nr_asids; 68 static unsigned long *sev_asid_bitmap; 69 static unsigned long *sev_reclaim_asid_bitmap; 70 71 struct enc_region { 72 struct list_head list; 73 unsigned long npages; 74 struct page **pages; 75 unsigned long uaddr; 76 unsigned long size; 77 }; 78 79 /* Called with the sev_bitmap_lock held, or on shutdown */ 80 static int sev_flush_asids(int min_asid, int max_asid) 81 { 82 int ret, asid, error = 0; 83 84 /* Check if there are any ASIDs to reclaim before performing a flush */ 85 asid = find_next_bit(sev_reclaim_asid_bitmap, nr_asids, min_asid); 86 if (asid > max_asid) 87 return -EBUSY; 88 89 /* 90 * DEACTIVATE will clear the WBINVD indicator causing DF_FLUSH to fail, 91 * so it must be guarded. 92 */ 93 down_write(&sev_deactivate_lock); 94 95 wbinvd_on_all_cpus(); 96 ret = sev_guest_df_flush(&error); 97 98 up_write(&sev_deactivate_lock); 99 100 if (ret) 101 pr_err("SEV: DF_FLUSH failed, ret=%d, error=%#x\n", ret, error); 102 103 return ret; 104 } 105 106 static inline bool is_mirroring_enc_context(struct kvm *kvm) 107 { 108 return !!to_kvm_svm(kvm)->sev_info.enc_context_owner; 109 } 110 111 /* Must be called with the sev_bitmap_lock held */ 112 static bool __sev_recycle_asids(int min_asid, int max_asid) 113 { 114 if (sev_flush_asids(min_asid, max_asid)) 115 return false; 116 117 /* The flush process will flush all reclaimable SEV and SEV-ES ASIDs */ 118 bitmap_xor(sev_asid_bitmap, sev_asid_bitmap, sev_reclaim_asid_bitmap, 119 nr_asids); 120 bitmap_zero(sev_reclaim_asid_bitmap, nr_asids); 121 122 return true; 123 } 124 125 static int sev_misc_cg_try_charge(struct kvm_sev_info *sev) 126 { 127 enum misc_res_type type = sev->es_active ? MISC_CG_RES_SEV_ES : MISC_CG_RES_SEV; 128 return misc_cg_try_charge(type, sev->misc_cg, 1); 129 } 130 131 static void sev_misc_cg_uncharge(struct kvm_sev_info *sev) 132 { 133 enum misc_res_type type = sev->es_active ? MISC_CG_RES_SEV_ES : MISC_CG_RES_SEV; 134 misc_cg_uncharge(type, sev->misc_cg, 1); 135 } 136 137 static int sev_asid_new(struct kvm_sev_info *sev) 138 { 139 int asid, min_asid, max_asid, ret; 140 bool retry = true; 141 142 WARN_ON(sev->misc_cg); 143 sev->misc_cg = get_current_misc_cg(); 144 ret = sev_misc_cg_try_charge(sev); 145 if (ret) { 146 put_misc_cg(sev->misc_cg); 147 sev->misc_cg = NULL; 148 return ret; 149 } 150 151 mutex_lock(&sev_bitmap_lock); 152 153 /* 154 * SEV-enabled guests must use asid from min_sev_asid to max_sev_asid. 155 * SEV-ES-enabled guest can use from 1 to min_sev_asid - 1. 156 */ 157 min_asid = sev->es_active ? 1 : min_sev_asid; 158 max_asid = sev->es_active ? min_sev_asid - 1 : max_sev_asid; 159 again: 160 asid = find_next_zero_bit(sev_asid_bitmap, max_asid + 1, min_asid); 161 if (asid > max_asid) { 162 if (retry && __sev_recycle_asids(min_asid, max_asid)) { 163 retry = false; 164 goto again; 165 } 166 mutex_unlock(&sev_bitmap_lock); 167 ret = -EBUSY; 168 goto e_uncharge; 169 } 170 171 __set_bit(asid, sev_asid_bitmap); 172 173 mutex_unlock(&sev_bitmap_lock); 174 175 return asid; 176 e_uncharge: 177 sev_misc_cg_uncharge(sev); 178 put_misc_cg(sev->misc_cg); 179 sev->misc_cg = NULL; 180 return ret; 181 } 182 183 static int sev_get_asid(struct kvm *kvm) 184 { 185 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 186 187 return sev->asid; 188 } 189 190 static void sev_asid_free(struct kvm_sev_info *sev) 191 { 192 struct svm_cpu_data *sd; 193 int cpu; 194 195 mutex_lock(&sev_bitmap_lock); 196 197 __set_bit(sev->asid, sev_reclaim_asid_bitmap); 198 199 for_each_possible_cpu(cpu) { 200 sd = per_cpu_ptr(&svm_data, cpu); 201 sd->sev_vmcbs[sev->asid] = NULL; 202 } 203 204 mutex_unlock(&sev_bitmap_lock); 205 206 sev_misc_cg_uncharge(sev); 207 put_misc_cg(sev->misc_cg); 208 sev->misc_cg = NULL; 209 } 210 211 static void sev_decommission(unsigned int handle) 212 { 213 struct sev_data_decommission decommission; 214 215 if (!handle) 216 return; 217 218 decommission.handle = handle; 219 sev_guest_decommission(&decommission, NULL); 220 } 221 222 static void sev_unbind_asid(struct kvm *kvm, unsigned int handle) 223 { 224 struct sev_data_deactivate deactivate; 225 226 if (!handle) 227 return; 228 229 deactivate.handle = handle; 230 231 /* Guard DEACTIVATE against WBINVD/DF_FLUSH used in ASID recycling */ 232 down_read(&sev_deactivate_lock); 233 sev_guest_deactivate(&deactivate, NULL); 234 up_read(&sev_deactivate_lock); 235 236 sev_decommission(handle); 237 } 238 239 static int sev_guest_init(struct kvm *kvm, struct kvm_sev_cmd *argp) 240 { 241 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 242 int asid, ret; 243 244 if (kvm->created_vcpus) 245 return -EINVAL; 246 247 ret = -EBUSY; 248 if (unlikely(sev->active)) 249 return ret; 250 251 sev->active = true; 252 sev->es_active = argp->id == KVM_SEV_ES_INIT; 253 asid = sev_asid_new(sev); 254 if (asid < 0) 255 goto e_no_asid; 256 sev->asid = asid; 257 258 ret = sev_platform_init(&argp->error); 259 if (ret) 260 goto e_free; 261 262 INIT_LIST_HEAD(&sev->regions_list); 263 INIT_LIST_HEAD(&sev->mirror_vms); 264 265 kvm_set_apicv_inhibit(kvm, APICV_INHIBIT_REASON_SEV); 266 267 return 0; 268 269 e_free: 270 sev_asid_free(sev); 271 sev->asid = 0; 272 e_no_asid: 273 sev->es_active = false; 274 sev->active = false; 275 return ret; 276 } 277 278 static int sev_bind_asid(struct kvm *kvm, unsigned int handle, int *error) 279 { 280 struct sev_data_activate activate; 281 int asid = sev_get_asid(kvm); 282 int ret; 283 284 /* activate ASID on the given handle */ 285 activate.handle = handle; 286 activate.asid = asid; 287 ret = sev_guest_activate(&activate, error); 288 289 return ret; 290 } 291 292 static int __sev_issue_cmd(int fd, int id, void *data, int *error) 293 { 294 struct fd f; 295 int ret; 296 297 f = fdget(fd); 298 if (!f.file) 299 return -EBADF; 300 301 ret = sev_issue_cmd_external_user(f.file, id, data, error); 302 303 fdput(f); 304 return ret; 305 } 306 307 static int sev_issue_cmd(struct kvm *kvm, int id, void *data, int *error) 308 { 309 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 310 311 return __sev_issue_cmd(sev->fd, id, data, error); 312 } 313 314 static int sev_launch_start(struct kvm *kvm, struct kvm_sev_cmd *argp) 315 { 316 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 317 struct sev_data_launch_start start; 318 struct kvm_sev_launch_start params; 319 void *dh_blob, *session_blob; 320 int *error = &argp->error; 321 int ret; 322 323 if (!sev_guest(kvm)) 324 return -ENOTTY; 325 326 if (copy_from_user(¶ms, (void __user *)(uintptr_t)argp->data, sizeof(params))) 327 return -EFAULT; 328 329 memset(&start, 0, sizeof(start)); 330 331 dh_blob = NULL; 332 if (params.dh_uaddr) { 333 dh_blob = psp_copy_user_blob(params.dh_uaddr, params.dh_len); 334 if (IS_ERR(dh_blob)) 335 return PTR_ERR(dh_blob); 336 337 start.dh_cert_address = __sme_set(__pa(dh_blob)); 338 start.dh_cert_len = params.dh_len; 339 } 340 341 session_blob = NULL; 342 if (params.session_uaddr) { 343 session_blob = psp_copy_user_blob(params.session_uaddr, params.session_len); 344 if (IS_ERR(session_blob)) { 345 ret = PTR_ERR(session_blob); 346 goto e_free_dh; 347 } 348 349 start.session_address = __sme_set(__pa(session_blob)); 350 start.session_len = params.session_len; 351 } 352 353 start.handle = params.handle; 354 start.policy = params.policy; 355 356 /* create memory encryption context */ 357 ret = __sev_issue_cmd(argp->sev_fd, SEV_CMD_LAUNCH_START, &start, error); 358 if (ret) 359 goto e_free_session; 360 361 /* Bind ASID to this guest */ 362 ret = sev_bind_asid(kvm, start.handle, error); 363 if (ret) { 364 sev_decommission(start.handle); 365 goto e_free_session; 366 } 367 368 /* return handle to userspace */ 369 params.handle = start.handle; 370 if (copy_to_user((void __user *)(uintptr_t)argp->data, ¶ms, sizeof(params))) { 371 sev_unbind_asid(kvm, start.handle); 372 ret = -EFAULT; 373 goto e_free_session; 374 } 375 376 sev->handle = start.handle; 377 sev->fd = argp->sev_fd; 378 379 e_free_session: 380 kfree(session_blob); 381 e_free_dh: 382 kfree(dh_blob); 383 return ret; 384 } 385 386 static struct page **sev_pin_memory(struct kvm *kvm, unsigned long uaddr, 387 unsigned long ulen, unsigned long *n, 388 int write) 389 { 390 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 391 unsigned long npages, size; 392 int npinned; 393 unsigned long locked, lock_limit; 394 struct page **pages; 395 unsigned long first, last; 396 int ret; 397 398 lockdep_assert_held(&kvm->lock); 399 400 if (ulen == 0 || uaddr + ulen < uaddr) 401 return ERR_PTR(-EINVAL); 402 403 /* Calculate number of pages. */ 404 first = (uaddr & PAGE_MASK) >> PAGE_SHIFT; 405 last = ((uaddr + ulen - 1) & PAGE_MASK) >> PAGE_SHIFT; 406 npages = (last - first + 1); 407 408 locked = sev->pages_locked + npages; 409 lock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT; 410 if (locked > lock_limit && !capable(CAP_IPC_LOCK)) { 411 pr_err("SEV: %lu locked pages exceed the lock limit of %lu.\n", locked, lock_limit); 412 return ERR_PTR(-ENOMEM); 413 } 414 415 if (WARN_ON_ONCE(npages > INT_MAX)) 416 return ERR_PTR(-EINVAL); 417 418 /* Avoid using vmalloc for smaller buffers. */ 419 size = npages * sizeof(struct page *); 420 if (size > PAGE_SIZE) 421 pages = __vmalloc(size, GFP_KERNEL_ACCOUNT | __GFP_ZERO); 422 else 423 pages = kmalloc(size, GFP_KERNEL_ACCOUNT); 424 425 if (!pages) 426 return ERR_PTR(-ENOMEM); 427 428 /* Pin the user virtual address. */ 429 npinned = pin_user_pages_fast(uaddr, npages, write ? FOLL_WRITE : 0, pages); 430 if (npinned != npages) { 431 pr_err("SEV: Failure locking %lu pages.\n", npages); 432 ret = -ENOMEM; 433 goto err; 434 } 435 436 *n = npages; 437 sev->pages_locked = locked; 438 439 return pages; 440 441 err: 442 if (npinned > 0) 443 unpin_user_pages(pages, npinned); 444 445 kvfree(pages); 446 return ERR_PTR(ret); 447 } 448 449 static void sev_unpin_memory(struct kvm *kvm, struct page **pages, 450 unsigned long npages) 451 { 452 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 453 454 unpin_user_pages(pages, npages); 455 kvfree(pages); 456 sev->pages_locked -= npages; 457 } 458 459 static void sev_clflush_pages(struct page *pages[], unsigned long npages) 460 { 461 uint8_t *page_virtual; 462 unsigned long i; 463 464 if (this_cpu_has(X86_FEATURE_SME_COHERENT) || npages == 0 || 465 pages == NULL) 466 return; 467 468 for (i = 0; i < npages; i++) { 469 page_virtual = kmap_local_page(pages[i]); 470 clflush_cache_range(page_virtual, PAGE_SIZE); 471 kunmap_local(page_virtual); 472 cond_resched(); 473 } 474 } 475 476 static unsigned long get_num_contig_pages(unsigned long idx, 477 struct page **inpages, unsigned long npages) 478 { 479 unsigned long paddr, next_paddr; 480 unsigned long i = idx + 1, pages = 1; 481 482 /* find the number of contiguous pages starting from idx */ 483 paddr = __sme_page_pa(inpages[idx]); 484 while (i < npages) { 485 next_paddr = __sme_page_pa(inpages[i++]); 486 if ((paddr + PAGE_SIZE) == next_paddr) { 487 pages++; 488 paddr = next_paddr; 489 continue; 490 } 491 break; 492 } 493 494 return pages; 495 } 496 497 static int sev_launch_update_data(struct kvm *kvm, struct kvm_sev_cmd *argp) 498 { 499 unsigned long vaddr, vaddr_end, next_vaddr, npages, pages, size, i; 500 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 501 struct kvm_sev_launch_update_data params; 502 struct sev_data_launch_update_data data; 503 struct page **inpages; 504 int ret; 505 506 if (!sev_guest(kvm)) 507 return -ENOTTY; 508 509 if (copy_from_user(¶ms, (void __user *)(uintptr_t)argp->data, sizeof(params))) 510 return -EFAULT; 511 512 vaddr = params.uaddr; 513 size = params.len; 514 vaddr_end = vaddr + size; 515 516 /* Lock the user memory. */ 517 inpages = sev_pin_memory(kvm, vaddr, size, &npages, 1); 518 if (IS_ERR(inpages)) 519 return PTR_ERR(inpages); 520 521 /* 522 * Flush (on non-coherent CPUs) before LAUNCH_UPDATE encrypts pages in 523 * place; the cache may contain the data that was written unencrypted. 524 */ 525 sev_clflush_pages(inpages, npages); 526 527 data.reserved = 0; 528 data.handle = sev->handle; 529 530 for (i = 0; vaddr < vaddr_end; vaddr = next_vaddr, i += pages) { 531 int offset, len; 532 533 /* 534 * If the user buffer is not page-aligned, calculate the offset 535 * within the page. 536 */ 537 offset = vaddr & (PAGE_SIZE - 1); 538 539 /* Calculate the number of pages that can be encrypted in one go. */ 540 pages = get_num_contig_pages(i, inpages, npages); 541 542 len = min_t(size_t, ((pages * PAGE_SIZE) - offset), size); 543 544 data.len = len; 545 data.address = __sme_page_pa(inpages[i]) + offset; 546 ret = sev_issue_cmd(kvm, SEV_CMD_LAUNCH_UPDATE_DATA, &data, &argp->error); 547 if (ret) 548 goto e_unpin; 549 550 size -= len; 551 next_vaddr = vaddr + len; 552 } 553 554 e_unpin: 555 /* content of memory is updated, mark pages dirty */ 556 for (i = 0; i < npages; i++) { 557 set_page_dirty_lock(inpages[i]); 558 mark_page_accessed(inpages[i]); 559 } 560 /* unlock the user pages */ 561 sev_unpin_memory(kvm, inpages, npages); 562 return ret; 563 } 564 565 static int sev_es_sync_vmsa(struct vcpu_svm *svm) 566 { 567 struct sev_es_save_area *save = svm->sev_es.vmsa; 568 569 /* Check some debug related fields before encrypting the VMSA */ 570 if (svm->vcpu.guest_debug || (svm->vmcb->save.dr7 & ~DR7_FIXED_1)) 571 return -EINVAL; 572 573 /* 574 * SEV-ES will use a VMSA that is pointed to by the VMCB, not 575 * the traditional VMSA that is part of the VMCB. Copy the 576 * traditional VMSA as it has been built so far (in prep 577 * for LAUNCH_UPDATE_VMSA) to be the initial SEV-ES state. 578 */ 579 memcpy(save, &svm->vmcb->save, sizeof(svm->vmcb->save)); 580 581 /* Sync registgers */ 582 save->rax = svm->vcpu.arch.regs[VCPU_REGS_RAX]; 583 save->rbx = svm->vcpu.arch.regs[VCPU_REGS_RBX]; 584 save->rcx = svm->vcpu.arch.regs[VCPU_REGS_RCX]; 585 save->rdx = svm->vcpu.arch.regs[VCPU_REGS_RDX]; 586 save->rsp = svm->vcpu.arch.regs[VCPU_REGS_RSP]; 587 save->rbp = svm->vcpu.arch.regs[VCPU_REGS_RBP]; 588 save->rsi = svm->vcpu.arch.regs[VCPU_REGS_RSI]; 589 save->rdi = svm->vcpu.arch.regs[VCPU_REGS_RDI]; 590 #ifdef CONFIG_X86_64 591 save->r8 = svm->vcpu.arch.regs[VCPU_REGS_R8]; 592 save->r9 = svm->vcpu.arch.regs[VCPU_REGS_R9]; 593 save->r10 = svm->vcpu.arch.regs[VCPU_REGS_R10]; 594 save->r11 = svm->vcpu.arch.regs[VCPU_REGS_R11]; 595 save->r12 = svm->vcpu.arch.regs[VCPU_REGS_R12]; 596 save->r13 = svm->vcpu.arch.regs[VCPU_REGS_R13]; 597 save->r14 = svm->vcpu.arch.regs[VCPU_REGS_R14]; 598 save->r15 = svm->vcpu.arch.regs[VCPU_REGS_R15]; 599 #endif 600 save->rip = svm->vcpu.arch.regs[VCPU_REGS_RIP]; 601 602 /* Sync some non-GPR registers before encrypting */ 603 save->xcr0 = svm->vcpu.arch.xcr0; 604 save->pkru = svm->vcpu.arch.pkru; 605 save->xss = svm->vcpu.arch.ia32_xss; 606 save->dr6 = svm->vcpu.arch.dr6; 607 608 pr_debug("Virtual Machine Save Area (VMSA):\n"); 609 print_hex_dump_debug("", DUMP_PREFIX_NONE, 16, 1, save, sizeof(*save), false); 610 611 return 0; 612 } 613 614 static int __sev_launch_update_vmsa(struct kvm *kvm, struct kvm_vcpu *vcpu, 615 int *error) 616 { 617 struct sev_data_launch_update_vmsa vmsa; 618 struct vcpu_svm *svm = to_svm(vcpu); 619 int ret; 620 621 /* Perform some pre-encryption checks against the VMSA */ 622 ret = sev_es_sync_vmsa(svm); 623 if (ret) 624 return ret; 625 626 /* 627 * The LAUNCH_UPDATE_VMSA command will perform in-place encryption of 628 * the VMSA memory content (i.e it will write the same memory region 629 * with the guest's key), so invalidate it first. 630 */ 631 clflush_cache_range(svm->sev_es.vmsa, PAGE_SIZE); 632 633 vmsa.reserved = 0; 634 vmsa.handle = to_kvm_svm(kvm)->sev_info.handle; 635 vmsa.address = __sme_pa(svm->sev_es.vmsa); 636 vmsa.len = PAGE_SIZE; 637 ret = sev_issue_cmd(kvm, SEV_CMD_LAUNCH_UPDATE_VMSA, &vmsa, error); 638 if (ret) 639 return ret; 640 641 vcpu->arch.guest_state_protected = true; 642 return 0; 643 } 644 645 static int sev_launch_update_vmsa(struct kvm *kvm, struct kvm_sev_cmd *argp) 646 { 647 struct kvm_vcpu *vcpu; 648 unsigned long i; 649 int ret; 650 651 if (!sev_es_guest(kvm)) 652 return -ENOTTY; 653 654 kvm_for_each_vcpu(i, vcpu, kvm) { 655 ret = mutex_lock_killable(&vcpu->mutex); 656 if (ret) 657 return ret; 658 659 ret = __sev_launch_update_vmsa(kvm, vcpu, &argp->error); 660 661 mutex_unlock(&vcpu->mutex); 662 if (ret) 663 return ret; 664 } 665 666 return 0; 667 } 668 669 static int sev_launch_measure(struct kvm *kvm, struct kvm_sev_cmd *argp) 670 { 671 void __user *measure = (void __user *)(uintptr_t)argp->data; 672 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 673 struct sev_data_launch_measure data; 674 struct kvm_sev_launch_measure params; 675 void __user *p = NULL; 676 void *blob = NULL; 677 int ret; 678 679 if (!sev_guest(kvm)) 680 return -ENOTTY; 681 682 if (copy_from_user(¶ms, measure, sizeof(params))) 683 return -EFAULT; 684 685 memset(&data, 0, sizeof(data)); 686 687 /* User wants to query the blob length */ 688 if (!params.len) 689 goto cmd; 690 691 p = (void __user *)(uintptr_t)params.uaddr; 692 if (p) { 693 if (params.len > SEV_FW_BLOB_MAX_SIZE) 694 return -EINVAL; 695 696 blob = kzalloc(params.len, GFP_KERNEL_ACCOUNT); 697 if (!blob) 698 return -ENOMEM; 699 700 data.address = __psp_pa(blob); 701 data.len = params.len; 702 } 703 704 cmd: 705 data.handle = sev->handle; 706 ret = sev_issue_cmd(kvm, SEV_CMD_LAUNCH_MEASURE, &data, &argp->error); 707 708 /* 709 * If we query the session length, FW responded with expected data. 710 */ 711 if (!params.len) 712 goto done; 713 714 if (ret) 715 goto e_free_blob; 716 717 if (blob) { 718 if (copy_to_user(p, blob, params.len)) 719 ret = -EFAULT; 720 } 721 722 done: 723 params.len = data.len; 724 if (copy_to_user(measure, ¶ms, sizeof(params))) 725 ret = -EFAULT; 726 e_free_blob: 727 kfree(blob); 728 return ret; 729 } 730 731 static int sev_launch_finish(struct kvm *kvm, struct kvm_sev_cmd *argp) 732 { 733 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 734 struct sev_data_launch_finish data; 735 736 if (!sev_guest(kvm)) 737 return -ENOTTY; 738 739 data.handle = sev->handle; 740 return sev_issue_cmd(kvm, SEV_CMD_LAUNCH_FINISH, &data, &argp->error); 741 } 742 743 static int sev_guest_status(struct kvm *kvm, struct kvm_sev_cmd *argp) 744 { 745 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 746 struct kvm_sev_guest_status params; 747 struct sev_data_guest_status data; 748 int ret; 749 750 if (!sev_guest(kvm)) 751 return -ENOTTY; 752 753 memset(&data, 0, sizeof(data)); 754 755 data.handle = sev->handle; 756 ret = sev_issue_cmd(kvm, SEV_CMD_GUEST_STATUS, &data, &argp->error); 757 if (ret) 758 return ret; 759 760 params.policy = data.policy; 761 params.state = data.state; 762 params.handle = data.handle; 763 764 if (copy_to_user((void __user *)(uintptr_t)argp->data, ¶ms, sizeof(params))) 765 ret = -EFAULT; 766 767 return ret; 768 } 769 770 static int __sev_issue_dbg_cmd(struct kvm *kvm, unsigned long src, 771 unsigned long dst, int size, 772 int *error, bool enc) 773 { 774 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 775 struct sev_data_dbg data; 776 777 data.reserved = 0; 778 data.handle = sev->handle; 779 data.dst_addr = dst; 780 data.src_addr = src; 781 data.len = size; 782 783 return sev_issue_cmd(kvm, 784 enc ? SEV_CMD_DBG_ENCRYPT : SEV_CMD_DBG_DECRYPT, 785 &data, error); 786 } 787 788 static int __sev_dbg_decrypt(struct kvm *kvm, unsigned long src_paddr, 789 unsigned long dst_paddr, int sz, int *err) 790 { 791 int offset; 792 793 /* 794 * Its safe to read more than we are asked, caller should ensure that 795 * destination has enough space. 796 */ 797 offset = src_paddr & 15; 798 src_paddr = round_down(src_paddr, 16); 799 sz = round_up(sz + offset, 16); 800 801 return __sev_issue_dbg_cmd(kvm, src_paddr, dst_paddr, sz, err, false); 802 } 803 804 static int __sev_dbg_decrypt_user(struct kvm *kvm, unsigned long paddr, 805 void __user *dst_uaddr, 806 unsigned long dst_paddr, 807 int size, int *err) 808 { 809 struct page *tpage = NULL; 810 int ret, offset; 811 812 /* if inputs are not 16-byte then use intermediate buffer */ 813 if (!IS_ALIGNED(dst_paddr, 16) || 814 !IS_ALIGNED(paddr, 16) || 815 !IS_ALIGNED(size, 16)) { 816 tpage = (void *)alloc_page(GFP_KERNEL_ACCOUNT | __GFP_ZERO); 817 if (!tpage) 818 return -ENOMEM; 819 820 dst_paddr = __sme_page_pa(tpage); 821 } 822 823 ret = __sev_dbg_decrypt(kvm, paddr, dst_paddr, size, err); 824 if (ret) 825 goto e_free; 826 827 if (tpage) { 828 offset = paddr & 15; 829 if (copy_to_user(dst_uaddr, page_address(tpage) + offset, size)) 830 ret = -EFAULT; 831 } 832 833 e_free: 834 if (tpage) 835 __free_page(tpage); 836 837 return ret; 838 } 839 840 static int __sev_dbg_encrypt_user(struct kvm *kvm, unsigned long paddr, 841 void __user *vaddr, 842 unsigned long dst_paddr, 843 void __user *dst_vaddr, 844 int size, int *error) 845 { 846 struct page *src_tpage = NULL; 847 struct page *dst_tpage = NULL; 848 int ret, len = size; 849 850 /* If source buffer is not aligned then use an intermediate buffer */ 851 if (!IS_ALIGNED((unsigned long)vaddr, 16)) { 852 src_tpage = alloc_page(GFP_KERNEL_ACCOUNT); 853 if (!src_tpage) 854 return -ENOMEM; 855 856 if (copy_from_user(page_address(src_tpage), vaddr, size)) { 857 __free_page(src_tpage); 858 return -EFAULT; 859 } 860 861 paddr = __sme_page_pa(src_tpage); 862 } 863 864 /* 865 * If destination buffer or length is not aligned then do read-modify-write: 866 * - decrypt destination in an intermediate buffer 867 * - copy the source buffer in an intermediate buffer 868 * - use the intermediate buffer as source buffer 869 */ 870 if (!IS_ALIGNED((unsigned long)dst_vaddr, 16) || !IS_ALIGNED(size, 16)) { 871 int dst_offset; 872 873 dst_tpage = alloc_page(GFP_KERNEL_ACCOUNT); 874 if (!dst_tpage) { 875 ret = -ENOMEM; 876 goto e_free; 877 } 878 879 ret = __sev_dbg_decrypt(kvm, dst_paddr, 880 __sme_page_pa(dst_tpage), size, error); 881 if (ret) 882 goto e_free; 883 884 /* 885 * If source is kernel buffer then use memcpy() otherwise 886 * copy_from_user(). 887 */ 888 dst_offset = dst_paddr & 15; 889 890 if (src_tpage) 891 memcpy(page_address(dst_tpage) + dst_offset, 892 page_address(src_tpage), size); 893 else { 894 if (copy_from_user(page_address(dst_tpage) + dst_offset, 895 vaddr, size)) { 896 ret = -EFAULT; 897 goto e_free; 898 } 899 } 900 901 paddr = __sme_page_pa(dst_tpage); 902 dst_paddr = round_down(dst_paddr, 16); 903 len = round_up(size, 16); 904 } 905 906 ret = __sev_issue_dbg_cmd(kvm, paddr, dst_paddr, len, error, true); 907 908 e_free: 909 if (src_tpage) 910 __free_page(src_tpage); 911 if (dst_tpage) 912 __free_page(dst_tpage); 913 return ret; 914 } 915 916 static int sev_dbg_crypt(struct kvm *kvm, struct kvm_sev_cmd *argp, bool dec) 917 { 918 unsigned long vaddr, vaddr_end, next_vaddr; 919 unsigned long dst_vaddr; 920 struct page **src_p, **dst_p; 921 struct kvm_sev_dbg debug; 922 unsigned long n; 923 unsigned int size; 924 int ret; 925 926 if (!sev_guest(kvm)) 927 return -ENOTTY; 928 929 if (copy_from_user(&debug, (void __user *)(uintptr_t)argp->data, sizeof(debug))) 930 return -EFAULT; 931 932 if (!debug.len || debug.src_uaddr + debug.len < debug.src_uaddr) 933 return -EINVAL; 934 if (!debug.dst_uaddr) 935 return -EINVAL; 936 937 vaddr = debug.src_uaddr; 938 size = debug.len; 939 vaddr_end = vaddr + size; 940 dst_vaddr = debug.dst_uaddr; 941 942 for (; vaddr < vaddr_end; vaddr = next_vaddr) { 943 int len, s_off, d_off; 944 945 /* lock userspace source and destination page */ 946 src_p = sev_pin_memory(kvm, vaddr & PAGE_MASK, PAGE_SIZE, &n, 0); 947 if (IS_ERR(src_p)) 948 return PTR_ERR(src_p); 949 950 dst_p = sev_pin_memory(kvm, dst_vaddr & PAGE_MASK, PAGE_SIZE, &n, 1); 951 if (IS_ERR(dst_p)) { 952 sev_unpin_memory(kvm, src_p, n); 953 return PTR_ERR(dst_p); 954 } 955 956 /* 957 * Flush (on non-coherent CPUs) before DBG_{DE,EN}CRYPT read or modify 958 * the pages; flush the destination too so that future accesses do not 959 * see stale data. 960 */ 961 sev_clflush_pages(src_p, 1); 962 sev_clflush_pages(dst_p, 1); 963 964 /* 965 * Since user buffer may not be page aligned, calculate the 966 * offset within the page. 967 */ 968 s_off = vaddr & ~PAGE_MASK; 969 d_off = dst_vaddr & ~PAGE_MASK; 970 len = min_t(size_t, (PAGE_SIZE - s_off), size); 971 972 if (dec) 973 ret = __sev_dbg_decrypt_user(kvm, 974 __sme_page_pa(src_p[0]) + s_off, 975 (void __user *)dst_vaddr, 976 __sme_page_pa(dst_p[0]) + d_off, 977 len, &argp->error); 978 else 979 ret = __sev_dbg_encrypt_user(kvm, 980 __sme_page_pa(src_p[0]) + s_off, 981 (void __user *)vaddr, 982 __sme_page_pa(dst_p[0]) + d_off, 983 (void __user *)dst_vaddr, 984 len, &argp->error); 985 986 sev_unpin_memory(kvm, src_p, n); 987 sev_unpin_memory(kvm, dst_p, n); 988 989 if (ret) 990 goto err; 991 992 next_vaddr = vaddr + len; 993 dst_vaddr = dst_vaddr + len; 994 size -= len; 995 } 996 err: 997 return ret; 998 } 999 1000 static int sev_launch_secret(struct kvm *kvm, struct kvm_sev_cmd *argp) 1001 { 1002 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 1003 struct sev_data_launch_secret data; 1004 struct kvm_sev_launch_secret params; 1005 struct page **pages; 1006 void *blob, *hdr; 1007 unsigned long n, i; 1008 int ret, offset; 1009 1010 if (!sev_guest(kvm)) 1011 return -ENOTTY; 1012 1013 if (copy_from_user(¶ms, (void __user *)(uintptr_t)argp->data, sizeof(params))) 1014 return -EFAULT; 1015 1016 pages = sev_pin_memory(kvm, params.guest_uaddr, params.guest_len, &n, 1); 1017 if (IS_ERR(pages)) 1018 return PTR_ERR(pages); 1019 1020 /* 1021 * Flush (on non-coherent CPUs) before LAUNCH_SECRET encrypts pages in 1022 * place; the cache may contain the data that was written unencrypted. 1023 */ 1024 sev_clflush_pages(pages, n); 1025 1026 /* 1027 * The secret must be copied into contiguous memory region, lets verify 1028 * that userspace memory pages are contiguous before we issue command. 1029 */ 1030 if (get_num_contig_pages(0, pages, n) != n) { 1031 ret = -EINVAL; 1032 goto e_unpin_memory; 1033 } 1034 1035 memset(&data, 0, sizeof(data)); 1036 1037 offset = params.guest_uaddr & (PAGE_SIZE - 1); 1038 data.guest_address = __sme_page_pa(pages[0]) + offset; 1039 data.guest_len = params.guest_len; 1040 1041 blob = psp_copy_user_blob(params.trans_uaddr, params.trans_len); 1042 if (IS_ERR(blob)) { 1043 ret = PTR_ERR(blob); 1044 goto e_unpin_memory; 1045 } 1046 1047 data.trans_address = __psp_pa(blob); 1048 data.trans_len = params.trans_len; 1049 1050 hdr = psp_copy_user_blob(params.hdr_uaddr, params.hdr_len); 1051 if (IS_ERR(hdr)) { 1052 ret = PTR_ERR(hdr); 1053 goto e_free_blob; 1054 } 1055 data.hdr_address = __psp_pa(hdr); 1056 data.hdr_len = params.hdr_len; 1057 1058 data.handle = sev->handle; 1059 ret = sev_issue_cmd(kvm, SEV_CMD_LAUNCH_UPDATE_SECRET, &data, &argp->error); 1060 1061 kfree(hdr); 1062 1063 e_free_blob: 1064 kfree(blob); 1065 e_unpin_memory: 1066 /* content of memory is updated, mark pages dirty */ 1067 for (i = 0; i < n; i++) { 1068 set_page_dirty_lock(pages[i]); 1069 mark_page_accessed(pages[i]); 1070 } 1071 sev_unpin_memory(kvm, pages, n); 1072 return ret; 1073 } 1074 1075 static int sev_get_attestation_report(struct kvm *kvm, struct kvm_sev_cmd *argp) 1076 { 1077 void __user *report = (void __user *)(uintptr_t)argp->data; 1078 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 1079 struct sev_data_attestation_report data; 1080 struct kvm_sev_attestation_report params; 1081 void __user *p; 1082 void *blob = NULL; 1083 int ret; 1084 1085 if (!sev_guest(kvm)) 1086 return -ENOTTY; 1087 1088 if (copy_from_user(¶ms, (void __user *)(uintptr_t)argp->data, sizeof(params))) 1089 return -EFAULT; 1090 1091 memset(&data, 0, sizeof(data)); 1092 1093 /* User wants to query the blob length */ 1094 if (!params.len) 1095 goto cmd; 1096 1097 p = (void __user *)(uintptr_t)params.uaddr; 1098 if (p) { 1099 if (params.len > SEV_FW_BLOB_MAX_SIZE) 1100 return -EINVAL; 1101 1102 blob = kzalloc(params.len, GFP_KERNEL_ACCOUNT); 1103 if (!blob) 1104 return -ENOMEM; 1105 1106 data.address = __psp_pa(blob); 1107 data.len = params.len; 1108 memcpy(data.mnonce, params.mnonce, sizeof(params.mnonce)); 1109 } 1110 cmd: 1111 data.handle = sev->handle; 1112 ret = sev_issue_cmd(kvm, SEV_CMD_ATTESTATION_REPORT, &data, &argp->error); 1113 /* 1114 * If we query the session length, FW responded with expected data. 1115 */ 1116 if (!params.len) 1117 goto done; 1118 1119 if (ret) 1120 goto e_free_blob; 1121 1122 if (blob) { 1123 if (copy_to_user(p, blob, params.len)) 1124 ret = -EFAULT; 1125 } 1126 1127 done: 1128 params.len = data.len; 1129 if (copy_to_user(report, ¶ms, sizeof(params))) 1130 ret = -EFAULT; 1131 e_free_blob: 1132 kfree(blob); 1133 return ret; 1134 } 1135 1136 /* Userspace wants to query session length. */ 1137 static int 1138 __sev_send_start_query_session_length(struct kvm *kvm, struct kvm_sev_cmd *argp, 1139 struct kvm_sev_send_start *params) 1140 { 1141 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 1142 struct sev_data_send_start data; 1143 int ret; 1144 1145 memset(&data, 0, sizeof(data)); 1146 data.handle = sev->handle; 1147 ret = sev_issue_cmd(kvm, SEV_CMD_SEND_START, &data, &argp->error); 1148 1149 params->session_len = data.session_len; 1150 if (copy_to_user((void __user *)(uintptr_t)argp->data, params, 1151 sizeof(struct kvm_sev_send_start))) 1152 ret = -EFAULT; 1153 1154 return ret; 1155 } 1156 1157 static int sev_send_start(struct kvm *kvm, struct kvm_sev_cmd *argp) 1158 { 1159 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 1160 struct sev_data_send_start data; 1161 struct kvm_sev_send_start params; 1162 void *amd_certs, *session_data; 1163 void *pdh_cert, *plat_certs; 1164 int ret; 1165 1166 if (!sev_guest(kvm)) 1167 return -ENOTTY; 1168 1169 if (copy_from_user(¶ms, (void __user *)(uintptr_t)argp->data, 1170 sizeof(struct kvm_sev_send_start))) 1171 return -EFAULT; 1172 1173 /* if session_len is zero, userspace wants to query the session length */ 1174 if (!params.session_len) 1175 return __sev_send_start_query_session_length(kvm, argp, 1176 ¶ms); 1177 1178 /* some sanity checks */ 1179 if (!params.pdh_cert_uaddr || !params.pdh_cert_len || 1180 !params.session_uaddr || params.session_len > SEV_FW_BLOB_MAX_SIZE) 1181 return -EINVAL; 1182 1183 /* allocate the memory to hold the session data blob */ 1184 session_data = kzalloc(params.session_len, GFP_KERNEL_ACCOUNT); 1185 if (!session_data) 1186 return -ENOMEM; 1187 1188 /* copy the certificate blobs from userspace */ 1189 pdh_cert = psp_copy_user_blob(params.pdh_cert_uaddr, 1190 params.pdh_cert_len); 1191 if (IS_ERR(pdh_cert)) { 1192 ret = PTR_ERR(pdh_cert); 1193 goto e_free_session; 1194 } 1195 1196 plat_certs = psp_copy_user_blob(params.plat_certs_uaddr, 1197 params.plat_certs_len); 1198 if (IS_ERR(plat_certs)) { 1199 ret = PTR_ERR(plat_certs); 1200 goto e_free_pdh; 1201 } 1202 1203 amd_certs = psp_copy_user_blob(params.amd_certs_uaddr, 1204 params.amd_certs_len); 1205 if (IS_ERR(amd_certs)) { 1206 ret = PTR_ERR(amd_certs); 1207 goto e_free_plat_cert; 1208 } 1209 1210 /* populate the FW SEND_START field with system physical address */ 1211 memset(&data, 0, sizeof(data)); 1212 data.pdh_cert_address = __psp_pa(pdh_cert); 1213 data.pdh_cert_len = params.pdh_cert_len; 1214 data.plat_certs_address = __psp_pa(plat_certs); 1215 data.plat_certs_len = params.plat_certs_len; 1216 data.amd_certs_address = __psp_pa(amd_certs); 1217 data.amd_certs_len = params.amd_certs_len; 1218 data.session_address = __psp_pa(session_data); 1219 data.session_len = params.session_len; 1220 data.handle = sev->handle; 1221 1222 ret = sev_issue_cmd(kvm, SEV_CMD_SEND_START, &data, &argp->error); 1223 1224 if (!ret && copy_to_user((void __user *)(uintptr_t)params.session_uaddr, 1225 session_data, params.session_len)) { 1226 ret = -EFAULT; 1227 goto e_free_amd_cert; 1228 } 1229 1230 params.policy = data.policy; 1231 params.session_len = data.session_len; 1232 if (copy_to_user((void __user *)(uintptr_t)argp->data, ¶ms, 1233 sizeof(struct kvm_sev_send_start))) 1234 ret = -EFAULT; 1235 1236 e_free_amd_cert: 1237 kfree(amd_certs); 1238 e_free_plat_cert: 1239 kfree(plat_certs); 1240 e_free_pdh: 1241 kfree(pdh_cert); 1242 e_free_session: 1243 kfree(session_data); 1244 return ret; 1245 } 1246 1247 /* Userspace wants to query either header or trans length. */ 1248 static int 1249 __sev_send_update_data_query_lengths(struct kvm *kvm, struct kvm_sev_cmd *argp, 1250 struct kvm_sev_send_update_data *params) 1251 { 1252 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 1253 struct sev_data_send_update_data data; 1254 int ret; 1255 1256 memset(&data, 0, sizeof(data)); 1257 data.handle = sev->handle; 1258 ret = sev_issue_cmd(kvm, SEV_CMD_SEND_UPDATE_DATA, &data, &argp->error); 1259 1260 params->hdr_len = data.hdr_len; 1261 params->trans_len = data.trans_len; 1262 1263 if (copy_to_user((void __user *)(uintptr_t)argp->data, params, 1264 sizeof(struct kvm_sev_send_update_data))) 1265 ret = -EFAULT; 1266 1267 return ret; 1268 } 1269 1270 static int sev_send_update_data(struct kvm *kvm, struct kvm_sev_cmd *argp) 1271 { 1272 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 1273 struct sev_data_send_update_data data; 1274 struct kvm_sev_send_update_data params; 1275 void *hdr, *trans_data; 1276 struct page **guest_page; 1277 unsigned long n; 1278 int ret, offset; 1279 1280 if (!sev_guest(kvm)) 1281 return -ENOTTY; 1282 1283 if (copy_from_user(¶ms, (void __user *)(uintptr_t)argp->data, 1284 sizeof(struct kvm_sev_send_update_data))) 1285 return -EFAULT; 1286 1287 /* userspace wants to query either header or trans length */ 1288 if (!params.trans_len || !params.hdr_len) 1289 return __sev_send_update_data_query_lengths(kvm, argp, ¶ms); 1290 1291 if (!params.trans_uaddr || !params.guest_uaddr || 1292 !params.guest_len || !params.hdr_uaddr) 1293 return -EINVAL; 1294 1295 /* Check if we are crossing the page boundary */ 1296 offset = params.guest_uaddr & (PAGE_SIZE - 1); 1297 if (params.guest_len > PAGE_SIZE || (params.guest_len + offset) > PAGE_SIZE) 1298 return -EINVAL; 1299 1300 /* Pin guest memory */ 1301 guest_page = sev_pin_memory(kvm, params.guest_uaddr & PAGE_MASK, 1302 PAGE_SIZE, &n, 0); 1303 if (IS_ERR(guest_page)) 1304 return PTR_ERR(guest_page); 1305 1306 /* allocate memory for header and transport buffer */ 1307 ret = -ENOMEM; 1308 hdr = kzalloc(params.hdr_len, GFP_KERNEL_ACCOUNT); 1309 if (!hdr) 1310 goto e_unpin; 1311 1312 trans_data = kzalloc(params.trans_len, GFP_KERNEL_ACCOUNT); 1313 if (!trans_data) 1314 goto e_free_hdr; 1315 1316 memset(&data, 0, sizeof(data)); 1317 data.hdr_address = __psp_pa(hdr); 1318 data.hdr_len = params.hdr_len; 1319 data.trans_address = __psp_pa(trans_data); 1320 data.trans_len = params.trans_len; 1321 1322 /* The SEND_UPDATE_DATA command requires C-bit to be always set. */ 1323 data.guest_address = (page_to_pfn(guest_page[0]) << PAGE_SHIFT) + offset; 1324 data.guest_address |= sev_me_mask; 1325 data.guest_len = params.guest_len; 1326 data.handle = sev->handle; 1327 1328 ret = sev_issue_cmd(kvm, SEV_CMD_SEND_UPDATE_DATA, &data, &argp->error); 1329 1330 if (ret) 1331 goto e_free_trans_data; 1332 1333 /* copy transport buffer to user space */ 1334 if (copy_to_user((void __user *)(uintptr_t)params.trans_uaddr, 1335 trans_data, params.trans_len)) { 1336 ret = -EFAULT; 1337 goto e_free_trans_data; 1338 } 1339 1340 /* Copy packet header to userspace. */ 1341 if (copy_to_user((void __user *)(uintptr_t)params.hdr_uaddr, hdr, 1342 params.hdr_len)) 1343 ret = -EFAULT; 1344 1345 e_free_trans_data: 1346 kfree(trans_data); 1347 e_free_hdr: 1348 kfree(hdr); 1349 e_unpin: 1350 sev_unpin_memory(kvm, guest_page, n); 1351 1352 return ret; 1353 } 1354 1355 static int sev_send_finish(struct kvm *kvm, struct kvm_sev_cmd *argp) 1356 { 1357 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 1358 struct sev_data_send_finish data; 1359 1360 if (!sev_guest(kvm)) 1361 return -ENOTTY; 1362 1363 data.handle = sev->handle; 1364 return sev_issue_cmd(kvm, SEV_CMD_SEND_FINISH, &data, &argp->error); 1365 } 1366 1367 static int sev_send_cancel(struct kvm *kvm, struct kvm_sev_cmd *argp) 1368 { 1369 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 1370 struct sev_data_send_cancel data; 1371 1372 if (!sev_guest(kvm)) 1373 return -ENOTTY; 1374 1375 data.handle = sev->handle; 1376 return sev_issue_cmd(kvm, SEV_CMD_SEND_CANCEL, &data, &argp->error); 1377 } 1378 1379 static int sev_receive_start(struct kvm *kvm, struct kvm_sev_cmd *argp) 1380 { 1381 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 1382 struct sev_data_receive_start start; 1383 struct kvm_sev_receive_start params; 1384 int *error = &argp->error; 1385 void *session_data; 1386 void *pdh_data; 1387 int ret; 1388 1389 if (!sev_guest(kvm)) 1390 return -ENOTTY; 1391 1392 /* Get parameter from the userspace */ 1393 if (copy_from_user(¶ms, (void __user *)(uintptr_t)argp->data, 1394 sizeof(struct kvm_sev_receive_start))) 1395 return -EFAULT; 1396 1397 /* some sanity checks */ 1398 if (!params.pdh_uaddr || !params.pdh_len || 1399 !params.session_uaddr || !params.session_len) 1400 return -EINVAL; 1401 1402 pdh_data = psp_copy_user_blob(params.pdh_uaddr, params.pdh_len); 1403 if (IS_ERR(pdh_data)) 1404 return PTR_ERR(pdh_data); 1405 1406 session_data = psp_copy_user_blob(params.session_uaddr, 1407 params.session_len); 1408 if (IS_ERR(session_data)) { 1409 ret = PTR_ERR(session_data); 1410 goto e_free_pdh; 1411 } 1412 1413 memset(&start, 0, sizeof(start)); 1414 start.handle = params.handle; 1415 start.policy = params.policy; 1416 start.pdh_cert_address = __psp_pa(pdh_data); 1417 start.pdh_cert_len = params.pdh_len; 1418 start.session_address = __psp_pa(session_data); 1419 start.session_len = params.session_len; 1420 1421 /* create memory encryption context */ 1422 ret = __sev_issue_cmd(argp->sev_fd, SEV_CMD_RECEIVE_START, &start, 1423 error); 1424 if (ret) 1425 goto e_free_session; 1426 1427 /* Bind ASID to this guest */ 1428 ret = sev_bind_asid(kvm, start.handle, error); 1429 if (ret) { 1430 sev_decommission(start.handle); 1431 goto e_free_session; 1432 } 1433 1434 params.handle = start.handle; 1435 if (copy_to_user((void __user *)(uintptr_t)argp->data, 1436 ¶ms, sizeof(struct kvm_sev_receive_start))) { 1437 ret = -EFAULT; 1438 sev_unbind_asid(kvm, start.handle); 1439 goto e_free_session; 1440 } 1441 1442 sev->handle = start.handle; 1443 sev->fd = argp->sev_fd; 1444 1445 e_free_session: 1446 kfree(session_data); 1447 e_free_pdh: 1448 kfree(pdh_data); 1449 1450 return ret; 1451 } 1452 1453 static int sev_receive_update_data(struct kvm *kvm, struct kvm_sev_cmd *argp) 1454 { 1455 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 1456 struct kvm_sev_receive_update_data params; 1457 struct sev_data_receive_update_data data; 1458 void *hdr = NULL, *trans = NULL; 1459 struct page **guest_page; 1460 unsigned long n; 1461 int ret, offset; 1462 1463 if (!sev_guest(kvm)) 1464 return -EINVAL; 1465 1466 if (copy_from_user(¶ms, (void __user *)(uintptr_t)argp->data, 1467 sizeof(struct kvm_sev_receive_update_data))) 1468 return -EFAULT; 1469 1470 if (!params.hdr_uaddr || !params.hdr_len || 1471 !params.guest_uaddr || !params.guest_len || 1472 !params.trans_uaddr || !params.trans_len) 1473 return -EINVAL; 1474 1475 /* Check if we are crossing the page boundary */ 1476 offset = params.guest_uaddr & (PAGE_SIZE - 1); 1477 if (params.guest_len > PAGE_SIZE || (params.guest_len + offset) > PAGE_SIZE) 1478 return -EINVAL; 1479 1480 hdr = psp_copy_user_blob(params.hdr_uaddr, params.hdr_len); 1481 if (IS_ERR(hdr)) 1482 return PTR_ERR(hdr); 1483 1484 trans = psp_copy_user_blob(params.trans_uaddr, params.trans_len); 1485 if (IS_ERR(trans)) { 1486 ret = PTR_ERR(trans); 1487 goto e_free_hdr; 1488 } 1489 1490 memset(&data, 0, sizeof(data)); 1491 data.hdr_address = __psp_pa(hdr); 1492 data.hdr_len = params.hdr_len; 1493 data.trans_address = __psp_pa(trans); 1494 data.trans_len = params.trans_len; 1495 1496 /* Pin guest memory */ 1497 guest_page = sev_pin_memory(kvm, params.guest_uaddr & PAGE_MASK, 1498 PAGE_SIZE, &n, 1); 1499 if (IS_ERR(guest_page)) { 1500 ret = PTR_ERR(guest_page); 1501 goto e_free_trans; 1502 } 1503 1504 /* 1505 * Flush (on non-coherent CPUs) before RECEIVE_UPDATE_DATA, the PSP 1506 * encrypts the written data with the guest's key, and the cache may 1507 * contain dirty, unencrypted data. 1508 */ 1509 sev_clflush_pages(guest_page, n); 1510 1511 /* The RECEIVE_UPDATE_DATA command requires C-bit to be always set. */ 1512 data.guest_address = (page_to_pfn(guest_page[0]) << PAGE_SHIFT) + offset; 1513 data.guest_address |= sev_me_mask; 1514 data.guest_len = params.guest_len; 1515 data.handle = sev->handle; 1516 1517 ret = sev_issue_cmd(kvm, SEV_CMD_RECEIVE_UPDATE_DATA, &data, 1518 &argp->error); 1519 1520 sev_unpin_memory(kvm, guest_page, n); 1521 1522 e_free_trans: 1523 kfree(trans); 1524 e_free_hdr: 1525 kfree(hdr); 1526 1527 return ret; 1528 } 1529 1530 static int sev_receive_finish(struct kvm *kvm, struct kvm_sev_cmd *argp) 1531 { 1532 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 1533 struct sev_data_receive_finish data; 1534 1535 if (!sev_guest(kvm)) 1536 return -ENOTTY; 1537 1538 data.handle = sev->handle; 1539 return sev_issue_cmd(kvm, SEV_CMD_RECEIVE_FINISH, &data, &argp->error); 1540 } 1541 1542 static bool is_cmd_allowed_from_mirror(u32 cmd_id) 1543 { 1544 /* 1545 * Allow mirrors VM to call KVM_SEV_LAUNCH_UPDATE_VMSA to enable SEV-ES 1546 * active mirror VMs. Also allow the debugging and status commands. 1547 */ 1548 if (cmd_id == KVM_SEV_LAUNCH_UPDATE_VMSA || 1549 cmd_id == KVM_SEV_GUEST_STATUS || cmd_id == KVM_SEV_DBG_DECRYPT || 1550 cmd_id == KVM_SEV_DBG_ENCRYPT) 1551 return true; 1552 1553 return false; 1554 } 1555 1556 static int sev_lock_two_vms(struct kvm *dst_kvm, struct kvm *src_kvm) 1557 { 1558 struct kvm_sev_info *dst_sev = &to_kvm_svm(dst_kvm)->sev_info; 1559 struct kvm_sev_info *src_sev = &to_kvm_svm(src_kvm)->sev_info; 1560 int r = -EBUSY; 1561 1562 if (dst_kvm == src_kvm) 1563 return -EINVAL; 1564 1565 /* 1566 * Bail if these VMs are already involved in a migration to avoid 1567 * deadlock between two VMs trying to migrate to/from each other. 1568 */ 1569 if (atomic_cmpxchg_acquire(&dst_sev->migration_in_progress, 0, 1)) 1570 return -EBUSY; 1571 1572 if (atomic_cmpxchg_acquire(&src_sev->migration_in_progress, 0, 1)) 1573 goto release_dst; 1574 1575 r = -EINTR; 1576 if (mutex_lock_killable(&dst_kvm->lock)) 1577 goto release_src; 1578 if (mutex_lock_killable_nested(&src_kvm->lock, SINGLE_DEPTH_NESTING)) 1579 goto unlock_dst; 1580 return 0; 1581 1582 unlock_dst: 1583 mutex_unlock(&dst_kvm->lock); 1584 release_src: 1585 atomic_set_release(&src_sev->migration_in_progress, 0); 1586 release_dst: 1587 atomic_set_release(&dst_sev->migration_in_progress, 0); 1588 return r; 1589 } 1590 1591 static void sev_unlock_two_vms(struct kvm *dst_kvm, struct kvm *src_kvm) 1592 { 1593 struct kvm_sev_info *dst_sev = &to_kvm_svm(dst_kvm)->sev_info; 1594 struct kvm_sev_info *src_sev = &to_kvm_svm(src_kvm)->sev_info; 1595 1596 mutex_unlock(&dst_kvm->lock); 1597 mutex_unlock(&src_kvm->lock); 1598 atomic_set_release(&dst_sev->migration_in_progress, 0); 1599 atomic_set_release(&src_sev->migration_in_progress, 0); 1600 } 1601 1602 /* vCPU mutex subclasses. */ 1603 enum sev_migration_role { 1604 SEV_MIGRATION_SOURCE = 0, 1605 SEV_MIGRATION_TARGET, 1606 SEV_NR_MIGRATION_ROLES, 1607 }; 1608 1609 static int sev_lock_vcpus_for_migration(struct kvm *kvm, 1610 enum sev_migration_role role) 1611 { 1612 struct kvm_vcpu *vcpu; 1613 unsigned long i, j; 1614 1615 kvm_for_each_vcpu(i, vcpu, kvm) { 1616 if (mutex_lock_killable_nested(&vcpu->mutex, role)) 1617 goto out_unlock; 1618 1619 #ifdef CONFIG_PROVE_LOCKING 1620 if (!i) 1621 /* 1622 * Reset the role to one that avoids colliding with 1623 * the role used for the first vcpu mutex. 1624 */ 1625 role = SEV_NR_MIGRATION_ROLES; 1626 else 1627 mutex_release(&vcpu->mutex.dep_map, _THIS_IP_); 1628 #endif 1629 } 1630 1631 return 0; 1632 1633 out_unlock: 1634 1635 kvm_for_each_vcpu(j, vcpu, kvm) { 1636 if (i == j) 1637 break; 1638 1639 #ifdef CONFIG_PROVE_LOCKING 1640 if (j) 1641 mutex_acquire(&vcpu->mutex.dep_map, role, 0, _THIS_IP_); 1642 #endif 1643 1644 mutex_unlock(&vcpu->mutex); 1645 } 1646 return -EINTR; 1647 } 1648 1649 static void sev_unlock_vcpus_for_migration(struct kvm *kvm) 1650 { 1651 struct kvm_vcpu *vcpu; 1652 unsigned long i; 1653 bool first = true; 1654 1655 kvm_for_each_vcpu(i, vcpu, kvm) { 1656 if (first) 1657 first = false; 1658 else 1659 mutex_acquire(&vcpu->mutex.dep_map, 1660 SEV_NR_MIGRATION_ROLES, 0, _THIS_IP_); 1661 1662 mutex_unlock(&vcpu->mutex); 1663 } 1664 } 1665 1666 static void sev_migrate_from(struct kvm *dst_kvm, struct kvm *src_kvm) 1667 { 1668 struct kvm_sev_info *dst = &to_kvm_svm(dst_kvm)->sev_info; 1669 struct kvm_sev_info *src = &to_kvm_svm(src_kvm)->sev_info; 1670 struct kvm_vcpu *dst_vcpu, *src_vcpu; 1671 struct vcpu_svm *dst_svm, *src_svm; 1672 struct kvm_sev_info *mirror; 1673 unsigned long i; 1674 1675 dst->active = true; 1676 dst->asid = src->asid; 1677 dst->handle = src->handle; 1678 dst->pages_locked = src->pages_locked; 1679 dst->enc_context_owner = src->enc_context_owner; 1680 dst->es_active = src->es_active; 1681 1682 src->asid = 0; 1683 src->active = false; 1684 src->handle = 0; 1685 src->pages_locked = 0; 1686 src->enc_context_owner = NULL; 1687 src->es_active = false; 1688 1689 list_cut_before(&dst->regions_list, &src->regions_list, &src->regions_list); 1690 1691 /* 1692 * If this VM has mirrors, "transfer" each mirror's refcount of the 1693 * source to the destination (this KVM). The caller holds a reference 1694 * to the source, so there's no danger of use-after-free. 1695 */ 1696 list_cut_before(&dst->mirror_vms, &src->mirror_vms, &src->mirror_vms); 1697 list_for_each_entry(mirror, &dst->mirror_vms, mirror_entry) { 1698 kvm_get_kvm(dst_kvm); 1699 kvm_put_kvm(src_kvm); 1700 mirror->enc_context_owner = dst_kvm; 1701 } 1702 1703 /* 1704 * If this VM is a mirror, remove the old mirror from the owners list 1705 * and add the new mirror to the list. 1706 */ 1707 if (is_mirroring_enc_context(dst_kvm)) { 1708 struct kvm_sev_info *owner_sev_info = 1709 &to_kvm_svm(dst->enc_context_owner)->sev_info; 1710 1711 list_del(&src->mirror_entry); 1712 list_add_tail(&dst->mirror_entry, &owner_sev_info->mirror_vms); 1713 } 1714 1715 kvm_for_each_vcpu(i, dst_vcpu, dst_kvm) { 1716 dst_svm = to_svm(dst_vcpu); 1717 1718 sev_init_vmcb(dst_svm); 1719 1720 if (!dst->es_active) 1721 continue; 1722 1723 /* 1724 * Note, the source is not required to have the same number of 1725 * vCPUs as the destination when migrating a vanilla SEV VM. 1726 */ 1727 src_vcpu = kvm_get_vcpu(dst_kvm, i); 1728 src_svm = to_svm(src_vcpu); 1729 1730 /* 1731 * Transfer VMSA and GHCB state to the destination. Nullify and 1732 * clear source fields as appropriate, the state now belongs to 1733 * the destination. 1734 */ 1735 memcpy(&dst_svm->sev_es, &src_svm->sev_es, sizeof(src_svm->sev_es)); 1736 dst_svm->vmcb->control.ghcb_gpa = src_svm->vmcb->control.ghcb_gpa; 1737 dst_svm->vmcb->control.vmsa_pa = src_svm->vmcb->control.vmsa_pa; 1738 dst_vcpu->arch.guest_state_protected = true; 1739 1740 memset(&src_svm->sev_es, 0, sizeof(src_svm->sev_es)); 1741 src_svm->vmcb->control.ghcb_gpa = INVALID_PAGE; 1742 src_svm->vmcb->control.vmsa_pa = INVALID_PAGE; 1743 src_vcpu->arch.guest_state_protected = false; 1744 } 1745 } 1746 1747 static int sev_check_source_vcpus(struct kvm *dst, struct kvm *src) 1748 { 1749 struct kvm_vcpu *src_vcpu; 1750 unsigned long i; 1751 1752 if (!sev_es_guest(src)) 1753 return 0; 1754 1755 if (atomic_read(&src->online_vcpus) != atomic_read(&dst->online_vcpus)) 1756 return -EINVAL; 1757 1758 kvm_for_each_vcpu(i, src_vcpu, src) { 1759 if (!src_vcpu->arch.guest_state_protected) 1760 return -EINVAL; 1761 } 1762 1763 return 0; 1764 } 1765 1766 int sev_vm_move_enc_context_from(struct kvm *kvm, unsigned int source_fd) 1767 { 1768 struct kvm_sev_info *dst_sev = &to_kvm_svm(kvm)->sev_info; 1769 struct kvm_sev_info *src_sev, *cg_cleanup_sev; 1770 struct file *source_kvm_file; 1771 struct kvm *source_kvm; 1772 bool charged = false; 1773 int ret; 1774 1775 source_kvm_file = fget(source_fd); 1776 if (!file_is_kvm(source_kvm_file)) { 1777 ret = -EBADF; 1778 goto out_fput; 1779 } 1780 1781 source_kvm = source_kvm_file->private_data; 1782 ret = sev_lock_two_vms(kvm, source_kvm); 1783 if (ret) 1784 goto out_fput; 1785 1786 if (sev_guest(kvm) || !sev_guest(source_kvm)) { 1787 ret = -EINVAL; 1788 goto out_unlock; 1789 } 1790 1791 src_sev = &to_kvm_svm(source_kvm)->sev_info; 1792 1793 dst_sev->misc_cg = get_current_misc_cg(); 1794 cg_cleanup_sev = dst_sev; 1795 if (dst_sev->misc_cg != src_sev->misc_cg) { 1796 ret = sev_misc_cg_try_charge(dst_sev); 1797 if (ret) 1798 goto out_dst_cgroup; 1799 charged = true; 1800 } 1801 1802 ret = sev_lock_vcpus_for_migration(kvm, SEV_MIGRATION_SOURCE); 1803 if (ret) 1804 goto out_dst_cgroup; 1805 ret = sev_lock_vcpus_for_migration(source_kvm, SEV_MIGRATION_TARGET); 1806 if (ret) 1807 goto out_dst_vcpu; 1808 1809 ret = sev_check_source_vcpus(kvm, source_kvm); 1810 if (ret) 1811 goto out_source_vcpu; 1812 1813 sev_migrate_from(kvm, source_kvm); 1814 kvm_vm_dead(source_kvm); 1815 cg_cleanup_sev = src_sev; 1816 ret = 0; 1817 1818 out_source_vcpu: 1819 sev_unlock_vcpus_for_migration(source_kvm); 1820 out_dst_vcpu: 1821 sev_unlock_vcpus_for_migration(kvm); 1822 out_dst_cgroup: 1823 /* Operates on the source on success, on the destination on failure. */ 1824 if (charged) 1825 sev_misc_cg_uncharge(cg_cleanup_sev); 1826 put_misc_cg(cg_cleanup_sev->misc_cg); 1827 cg_cleanup_sev->misc_cg = NULL; 1828 out_unlock: 1829 sev_unlock_two_vms(kvm, source_kvm); 1830 out_fput: 1831 if (source_kvm_file) 1832 fput(source_kvm_file); 1833 return ret; 1834 } 1835 1836 int sev_mem_enc_ioctl(struct kvm *kvm, void __user *argp) 1837 { 1838 struct kvm_sev_cmd sev_cmd; 1839 int r; 1840 1841 if (!sev_enabled) 1842 return -ENOTTY; 1843 1844 if (!argp) 1845 return 0; 1846 1847 if (copy_from_user(&sev_cmd, argp, sizeof(struct kvm_sev_cmd))) 1848 return -EFAULT; 1849 1850 mutex_lock(&kvm->lock); 1851 1852 /* Only the enc_context_owner handles some memory enc operations. */ 1853 if (is_mirroring_enc_context(kvm) && 1854 !is_cmd_allowed_from_mirror(sev_cmd.id)) { 1855 r = -EINVAL; 1856 goto out; 1857 } 1858 1859 switch (sev_cmd.id) { 1860 case KVM_SEV_ES_INIT: 1861 if (!sev_es_enabled) { 1862 r = -ENOTTY; 1863 goto out; 1864 } 1865 fallthrough; 1866 case KVM_SEV_INIT: 1867 r = sev_guest_init(kvm, &sev_cmd); 1868 break; 1869 case KVM_SEV_LAUNCH_START: 1870 r = sev_launch_start(kvm, &sev_cmd); 1871 break; 1872 case KVM_SEV_LAUNCH_UPDATE_DATA: 1873 r = sev_launch_update_data(kvm, &sev_cmd); 1874 break; 1875 case KVM_SEV_LAUNCH_UPDATE_VMSA: 1876 r = sev_launch_update_vmsa(kvm, &sev_cmd); 1877 break; 1878 case KVM_SEV_LAUNCH_MEASURE: 1879 r = sev_launch_measure(kvm, &sev_cmd); 1880 break; 1881 case KVM_SEV_LAUNCH_FINISH: 1882 r = sev_launch_finish(kvm, &sev_cmd); 1883 break; 1884 case KVM_SEV_GUEST_STATUS: 1885 r = sev_guest_status(kvm, &sev_cmd); 1886 break; 1887 case KVM_SEV_DBG_DECRYPT: 1888 r = sev_dbg_crypt(kvm, &sev_cmd, true); 1889 break; 1890 case KVM_SEV_DBG_ENCRYPT: 1891 r = sev_dbg_crypt(kvm, &sev_cmd, false); 1892 break; 1893 case KVM_SEV_LAUNCH_SECRET: 1894 r = sev_launch_secret(kvm, &sev_cmd); 1895 break; 1896 case KVM_SEV_GET_ATTESTATION_REPORT: 1897 r = sev_get_attestation_report(kvm, &sev_cmd); 1898 break; 1899 case KVM_SEV_SEND_START: 1900 r = sev_send_start(kvm, &sev_cmd); 1901 break; 1902 case KVM_SEV_SEND_UPDATE_DATA: 1903 r = sev_send_update_data(kvm, &sev_cmd); 1904 break; 1905 case KVM_SEV_SEND_FINISH: 1906 r = sev_send_finish(kvm, &sev_cmd); 1907 break; 1908 case KVM_SEV_SEND_CANCEL: 1909 r = sev_send_cancel(kvm, &sev_cmd); 1910 break; 1911 case KVM_SEV_RECEIVE_START: 1912 r = sev_receive_start(kvm, &sev_cmd); 1913 break; 1914 case KVM_SEV_RECEIVE_UPDATE_DATA: 1915 r = sev_receive_update_data(kvm, &sev_cmd); 1916 break; 1917 case KVM_SEV_RECEIVE_FINISH: 1918 r = sev_receive_finish(kvm, &sev_cmd); 1919 break; 1920 default: 1921 r = -EINVAL; 1922 goto out; 1923 } 1924 1925 if (copy_to_user(argp, &sev_cmd, sizeof(struct kvm_sev_cmd))) 1926 r = -EFAULT; 1927 1928 out: 1929 mutex_unlock(&kvm->lock); 1930 return r; 1931 } 1932 1933 int sev_mem_enc_register_region(struct kvm *kvm, 1934 struct kvm_enc_region *range) 1935 { 1936 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 1937 struct enc_region *region; 1938 int ret = 0; 1939 1940 if (!sev_guest(kvm)) 1941 return -ENOTTY; 1942 1943 /* If kvm is mirroring encryption context it isn't responsible for it */ 1944 if (is_mirroring_enc_context(kvm)) 1945 return -EINVAL; 1946 1947 if (range->addr > ULONG_MAX || range->size > ULONG_MAX) 1948 return -EINVAL; 1949 1950 region = kzalloc(sizeof(*region), GFP_KERNEL_ACCOUNT); 1951 if (!region) 1952 return -ENOMEM; 1953 1954 mutex_lock(&kvm->lock); 1955 region->pages = sev_pin_memory(kvm, range->addr, range->size, ®ion->npages, 1); 1956 if (IS_ERR(region->pages)) { 1957 ret = PTR_ERR(region->pages); 1958 mutex_unlock(&kvm->lock); 1959 goto e_free; 1960 } 1961 1962 region->uaddr = range->addr; 1963 region->size = range->size; 1964 1965 list_add_tail(®ion->list, &sev->regions_list); 1966 mutex_unlock(&kvm->lock); 1967 1968 /* 1969 * The guest may change the memory encryption attribute from C=0 -> C=1 1970 * or vice versa for this memory range. Lets make sure caches are 1971 * flushed to ensure that guest data gets written into memory with 1972 * correct C-bit. 1973 */ 1974 sev_clflush_pages(region->pages, region->npages); 1975 1976 return ret; 1977 1978 e_free: 1979 kfree(region); 1980 return ret; 1981 } 1982 1983 static struct enc_region * 1984 find_enc_region(struct kvm *kvm, struct kvm_enc_region *range) 1985 { 1986 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 1987 struct list_head *head = &sev->regions_list; 1988 struct enc_region *i; 1989 1990 list_for_each_entry(i, head, list) { 1991 if (i->uaddr == range->addr && 1992 i->size == range->size) 1993 return i; 1994 } 1995 1996 return NULL; 1997 } 1998 1999 static void __unregister_enc_region_locked(struct kvm *kvm, 2000 struct enc_region *region) 2001 { 2002 sev_unpin_memory(kvm, region->pages, region->npages); 2003 list_del(®ion->list); 2004 kfree(region); 2005 } 2006 2007 int sev_mem_enc_unregister_region(struct kvm *kvm, 2008 struct kvm_enc_region *range) 2009 { 2010 struct enc_region *region; 2011 int ret; 2012 2013 /* If kvm is mirroring encryption context it isn't responsible for it */ 2014 if (is_mirroring_enc_context(kvm)) 2015 return -EINVAL; 2016 2017 mutex_lock(&kvm->lock); 2018 2019 if (!sev_guest(kvm)) { 2020 ret = -ENOTTY; 2021 goto failed; 2022 } 2023 2024 region = find_enc_region(kvm, range); 2025 if (!region) { 2026 ret = -EINVAL; 2027 goto failed; 2028 } 2029 2030 /* 2031 * Ensure that all guest tagged cache entries are flushed before 2032 * releasing the pages back to the system for use. CLFLUSH will 2033 * not do this, so issue a WBINVD. 2034 */ 2035 wbinvd_on_all_cpus(); 2036 2037 __unregister_enc_region_locked(kvm, region); 2038 2039 mutex_unlock(&kvm->lock); 2040 return 0; 2041 2042 failed: 2043 mutex_unlock(&kvm->lock); 2044 return ret; 2045 } 2046 2047 int sev_vm_copy_enc_context_from(struct kvm *kvm, unsigned int source_fd) 2048 { 2049 struct file *source_kvm_file; 2050 struct kvm *source_kvm; 2051 struct kvm_sev_info *source_sev, *mirror_sev; 2052 int ret; 2053 2054 source_kvm_file = fget(source_fd); 2055 if (!file_is_kvm(source_kvm_file)) { 2056 ret = -EBADF; 2057 goto e_source_fput; 2058 } 2059 2060 source_kvm = source_kvm_file->private_data; 2061 ret = sev_lock_two_vms(kvm, source_kvm); 2062 if (ret) 2063 goto e_source_fput; 2064 2065 /* 2066 * Mirrors of mirrors should work, but let's not get silly. Also 2067 * disallow out-of-band SEV/SEV-ES init if the target is already an 2068 * SEV guest, or if vCPUs have been created. KVM relies on vCPUs being 2069 * created after SEV/SEV-ES initialization, e.g. to init intercepts. 2070 */ 2071 if (sev_guest(kvm) || !sev_guest(source_kvm) || 2072 is_mirroring_enc_context(source_kvm) || kvm->created_vcpus) { 2073 ret = -EINVAL; 2074 goto e_unlock; 2075 } 2076 2077 /* 2078 * The mirror kvm holds an enc_context_owner ref so its asid can't 2079 * disappear until we're done with it 2080 */ 2081 source_sev = &to_kvm_svm(source_kvm)->sev_info; 2082 kvm_get_kvm(source_kvm); 2083 mirror_sev = &to_kvm_svm(kvm)->sev_info; 2084 list_add_tail(&mirror_sev->mirror_entry, &source_sev->mirror_vms); 2085 2086 /* Set enc_context_owner and copy its encryption context over */ 2087 mirror_sev->enc_context_owner = source_kvm; 2088 mirror_sev->active = true; 2089 mirror_sev->asid = source_sev->asid; 2090 mirror_sev->fd = source_sev->fd; 2091 mirror_sev->es_active = source_sev->es_active; 2092 mirror_sev->handle = source_sev->handle; 2093 INIT_LIST_HEAD(&mirror_sev->regions_list); 2094 INIT_LIST_HEAD(&mirror_sev->mirror_vms); 2095 ret = 0; 2096 2097 /* 2098 * Do not copy ap_jump_table. Since the mirror does not share the same 2099 * KVM contexts as the original, and they may have different 2100 * memory-views. 2101 */ 2102 2103 e_unlock: 2104 sev_unlock_two_vms(kvm, source_kvm); 2105 e_source_fput: 2106 if (source_kvm_file) 2107 fput(source_kvm_file); 2108 return ret; 2109 } 2110 2111 void sev_vm_destroy(struct kvm *kvm) 2112 { 2113 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; 2114 struct list_head *head = &sev->regions_list; 2115 struct list_head *pos, *q; 2116 2117 if (!sev_guest(kvm)) 2118 return; 2119 2120 WARN_ON(!list_empty(&sev->mirror_vms)); 2121 2122 /* If this is a mirror_kvm release the enc_context_owner and skip sev cleanup */ 2123 if (is_mirroring_enc_context(kvm)) { 2124 struct kvm *owner_kvm = sev->enc_context_owner; 2125 2126 mutex_lock(&owner_kvm->lock); 2127 list_del(&sev->mirror_entry); 2128 mutex_unlock(&owner_kvm->lock); 2129 kvm_put_kvm(owner_kvm); 2130 return; 2131 } 2132 2133 /* 2134 * Ensure that all guest tagged cache entries are flushed before 2135 * releasing the pages back to the system for use. CLFLUSH will 2136 * not do this, so issue a WBINVD. 2137 */ 2138 wbinvd_on_all_cpus(); 2139 2140 /* 2141 * if userspace was terminated before unregistering the memory regions 2142 * then lets unpin all the registered memory. 2143 */ 2144 if (!list_empty(head)) { 2145 list_for_each_safe(pos, q, head) { 2146 __unregister_enc_region_locked(kvm, 2147 list_entry(pos, struct enc_region, list)); 2148 cond_resched(); 2149 } 2150 } 2151 2152 sev_unbind_asid(kvm, sev->handle); 2153 sev_asid_free(sev); 2154 } 2155 2156 void __init sev_set_cpu_caps(void) 2157 { 2158 if (!sev_enabled) 2159 kvm_cpu_cap_clear(X86_FEATURE_SEV); 2160 if (!sev_es_enabled) 2161 kvm_cpu_cap_clear(X86_FEATURE_SEV_ES); 2162 } 2163 2164 void __init sev_hardware_setup(void) 2165 { 2166 #ifdef CONFIG_KVM_AMD_SEV 2167 unsigned int eax, ebx, ecx, edx, sev_asid_count, sev_es_asid_count; 2168 bool sev_es_supported = false; 2169 bool sev_supported = false; 2170 2171 if (!sev_enabled || !npt_enabled) 2172 goto out; 2173 2174 /* 2175 * SEV must obviously be supported in hardware. Sanity check that the 2176 * CPU supports decode assists, which is mandatory for SEV guests to 2177 * support instruction emulation. 2178 */ 2179 if (!boot_cpu_has(X86_FEATURE_SEV) || 2180 WARN_ON_ONCE(!boot_cpu_has(X86_FEATURE_DECODEASSISTS))) 2181 goto out; 2182 2183 /* Retrieve SEV CPUID information */ 2184 cpuid(0x8000001f, &eax, &ebx, &ecx, &edx); 2185 2186 /* Set encryption bit location for SEV-ES guests */ 2187 sev_enc_bit = ebx & 0x3f; 2188 2189 /* Maximum number of encrypted guests supported simultaneously */ 2190 max_sev_asid = ecx; 2191 if (!max_sev_asid) 2192 goto out; 2193 2194 /* Minimum ASID value that should be used for SEV guest */ 2195 min_sev_asid = edx; 2196 sev_me_mask = 1UL << (ebx & 0x3f); 2197 2198 /* 2199 * Initialize SEV ASID bitmaps. Allocate space for ASID 0 in the bitmap, 2200 * even though it's never used, so that the bitmap is indexed by the 2201 * actual ASID. 2202 */ 2203 nr_asids = max_sev_asid + 1; 2204 sev_asid_bitmap = bitmap_zalloc(nr_asids, GFP_KERNEL); 2205 if (!sev_asid_bitmap) 2206 goto out; 2207 2208 sev_reclaim_asid_bitmap = bitmap_zalloc(nr_asids, GFP_KERNEL); 2209 if (!sev_reclaim_asid_bitmap) { 2210 bitmap_free(sev_asid_bitmap); 2211 sev_asid_bitmap = NULL; 2212 goto out; 2213 } 2214 2215 sev_asid_count = max_sev_asid - min_sev_asid + 1; 2216 if (misc_cg_set_capacity(MISC_CG_RES_SEV, sev_asid_count)) 2217 goto out; 2218 2219 pr_info("SEV supported: %u ASIDs\n", 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 if (misc_cg_set_capacity(MISC_CG_RES_SEV_ES, sev_es_asid_count)) 2245 goto out; 2246 2247 pr_info("SEV-ES supported: %u ASIDs\n", sev_es_asid_count); 2248 sev_es_supported = true; 2249 2250 out: 2251 sev_enabled = sev_supported; 2252 sev_es_enabled = sev_es_supported; 2253 #endif 2254 } 2255 2256 void sev_hardware_unsetup(void) 2257 { 2258 if (!sev_enabled) 2259 return; 2260 2261 /* No need to take sev_bitmap_lock, all VMs have been destroyed. */ 2262 sev_flush_asids(1, max_sev_asid); 2263 2264 bitmap_free(sev_asid_bitmap); 2265 bitmap_free(sev_reclaim_asid_bitmap); 2266 2267 misc_cg_set_capacity(MISC_CG_RES_SEV, 0); 2268 misc_cg_set_capacity(MISC_CG_RES_SEV_ES, 0); 2269 } 2270 2271 int sev_cpu_init(struct svm_cpu_data *sd) 2272 { 2273 if (!sev_enabled) 2274 return 0; 2275 2276 sd->sev_vmcbs = kcalloc(nr_asids, sizeof(void *), GFP_KERNEL); 2277 if (!sd->sev_vmcbs) 2278 return -ENOMEM; 2279 2280 return 0; 2281 } 2282 2283 /* 2284 * Pages used by hardware to hold guest encrypted state must be flushed before 2285 * returning them to the system. 2286 */ 2287 static void sev_flush_encrypted_page(struct kvm_vcpu *vcpu, void *va) 2288 { 2289 int asid = to_kvm_svm(vcpu->kvm)->sev_info.asid; 2290 2291 /* 2292 * Note! The address must be a kernel address, as regular page walk 2293 * checks are performed by VM_PAGE_FLUSH, i.e. operating on a user 2294 * address is non-deterministic and unsafe. This function deliberately 2295 * takes a pointer to deter passing in a user address. 2296 */ 2297 unsigned long addr = (unsigned long)va; 2298 2299 /* 2300 * If CPU enforced cache coherency for encrypted mappings of the 2301 * same physical page is supported, use CLFLUSHOPT instead. NOTE: cache 2302 * flush is still needed in order to work properly with DMA devices. 2303 */ 2304 if (boot_cpu_has(X86_FEATURE_SME_COHERENT)) { 2305 clflush_cache_range(va, PAGE_SIZE); 2306 return; 2307 } 2308 2309 /* 2310 * VM Page Flush takes a host virtual address and a guest ASID. Fall 2311 * back to WBINVD if this faults so as not to make any problems worse 2312 * by leaving stale encrypted data in the cache. 2313 */ 2314 if (WARN_ON_ONCE(wrmsrl_safe(MSR_AMD64_VM_PAGE_FLUSH, addr | asid))) 2315 goto do_wbinvd; 2316 2317 return; 2318 2319 do_wbinvd: 2320 wbinvd_on_all_cpus(); 2321 } 2322 2323 void sev_guest_memory_reclaimed(struct kvm *kvm) 2324 { 2325 if (!sev_guest(kvm)) 2326 return; 2327 2328 wbinvd_on_all_cpus(); 2329 } 2330 2331 void sev_free_vcpu(struct kvm_vcpu *vcpu) 2332 { 2333 struct vcpu_svm *svm; 2334 2335 if (!sev_es_guest(vcpu->kvm)) 2336 return; 2337 2338 svm = to_svm(vcpu); 2339 2340 if (vcpu->arch.guest_state_protected) 2341 sev_flush_encrypted_page(vcpu, svm->sev_es.vmsa); 2342 2343 __free_page(virt_to_page(svm->sev_es.vmsa)); 2344 2345 if (svm->sev_es.ghcb_sa_free) 2346 kvfree(svm->sev_es.ghcb_sa); 2347 } 2348 2349 static void dump_ghcb(struct vcpu_svm *svm) 2350 { 2351 struct ghcb *ghcb = svm->sev_es.ghcb; 2352 unsigned int nbits; 2353 2354 /* Re-use the dump_invalid_vmcb module parameter */ 2355 if (!dump_invalid_vmcb) { 2356 pr_warn_ratelimited("set kvm_amd.dump_invalid_vmcb=1 to dump internal KVM state.\n"); 2357 return; 2358 } 2359 2360 nbits = sizeof(ghcb->save.valid_bitmap) * 8; 2361 2362 pr_err("GHCB (GPA=%016llx):\n", svm->vmcb->control.ghcb_gpa); 2363 pr_err("%-20s%016llx is_valid: %u\n", "sw_exit_code", 2364 ghcb->save.sw_exit_code, ghcb_sw_exit_code_is_valid(ghcb)); 2365 pr_err("%-20s%016llx is_valid: %u\n", "sw_exit_info_1", 2366 ghcb->save.sw_exit_info_1, ghcb_sw_exit_info_1_is_valid(ghcb)); 2367 pr_err("%-20s%016llx is_valid: %u\n", "sw_exit_info_2", 2368 ghcb->save.sw_exit_info_2, ghcb_sw_exit_info_2_is_valid(ghcb)); 2369 pr_err("%-20s%016llx is_valid: %u\n", "sw_scratch", 2370 ghcb->save.sw_scratch, ghcb_sw_scratch_is_valid(ghcb)); 2371 pr_err("%-20s%*pb\n", "valid_bitmap", nbits, ghcb->save.valid_bitmap); 2372 } 2373 2374 static void sev_es_sync_to_ghcb(struct vcpu_svm *svm) 2375 { 2376 struct kvm_vcpu *vcpu = &svm->vcpu; 2377 struct ghcb *ghcb = svm->sev_es.ghcb; 2378 2379 /* 2380 * The GHCB protocol so far allows for the following data 2381 * to be returned: 2382 * GPRs RAX, RBX, RCX, RDX 2383 * 2384 * Copy their values, even if they may not have been written during the 2385 * VM-Exit. It's the guest's responsibility to not consume random data. 2386 */ 2387 ghcb_set_rax(ghcb, vcpu->arch.regs[VCPU_REGS_RAX]); 2388 ghcb_set_rbx(ghcb, vcpu->arch.regs[VCPU_REGS_RBX]); 2389 ghcb_set_rcx(ghcb, vcpu->arch.regs[VCPU_REGS_RCX]); 2390 ghcb_set_rdx(ghcb, vcpu->arch.regs[VCPU_REGS_RDX]); 2391 } 2392 2393 static void sev_es_sync_from_ghcb(struct vcpu_svm *svm) 2394 { 2395 struct vmcb_control_area *control = &svm->vmcb->control; 2396 struct kvm_vcpu *vcpu = &svm->vcpu; 2397 struct ghcb *ghcb = svm->sev_es.ghcb; 2398 u64 exit_code; 2399 2400 /* 2401 * The GHCB protocol so far allows for the following data 2402 * to be supplied: 2403 * GPRs RAX, RBX, RCX, RDX 2404 * XCR0 2405 * CPL 2406 * 2407 * VMMCALL allows the guest to provide extra registers. KVM also 2408 * expects RSI for hypercalls, so include that, too. 2409 * 2410 * Copy their values to the appropriate location if supplied. 2411 */ 2412 memset(vcpu->arch.regs, 0, sizeof(vcpu->arch.regs)); 2413 2414 vcpu->arch.regs[VCPU_REGS_RAX] = ghcb_get_rax_if_valid(ghcb); 2415 vcpu->arch.regs[VCPU_REGS_RBX] = ghcb_get_rbx_if_valid(ghcb); 2416 vcpu->arch.regs[VCPU_REGS_RCX] = ghcb_get_rcx_if_valid(ghcb); 2417 vcpu->arch.regs[VCPU_REGS_RDX] = ghcb_get_rdx_if_valid(ghcb); 2418 vcpu->arch.regs[VCPU_REGS_RSI] = ghcb_get_rsi_if_valid(ghcb); 2419 2420 svm->vmcb->save.cpl = ghcb_get_cpl_if_valid(ghcb); 2421 2422 if (ghcb_xcr0_is_valid(ghcb)) { 2423 vcpu->arch.xcr0 = ghcb_get_xcr0(ghcb); 2424 kvm_update_cpuid_runtime(vcpu); 2425 } 2426 2427 /* Copy the GHCB exit information into the VMCB fields */ 2428 exit_code = ghcb_get_sw_exit_code(ghcb); 2429 control->exit_code = lower_32_bits(exit_code); 2430 control->exit_code_hi = upper_32_bits(exit_code); 2431 control->exit_info_1 = ghcb_get_sw_exit_info_1(ghcb); 2432 control->exit_info_2 = ghcb_get_sw_exit_info_2(ghcb); 2433 2434 /* Clear the valid entries fields */ 2435 memset(ghcb->save.valid_bitmap, 0, sizeof(ghcb->save.valid_bitmap)); 2436 } 2437 2438 static int sev_es_validate_vmgexit(struct vcpu_svm *svm) 2439 { 2440 struct kvm_vcpu *vcpu; 2441 struct ghcb *ghcb; 2442 u64 exit_code; 2443 u64 reason; 2444 2445 ghcb = svm->sev_es.ghcb; 2446 2447 /* 2448 * Retrieve the exit code now even though it may not be marked valid 2449 * as it could help with debugging. 2450 */ 2451 exit_code = ghcb_get_sw_exit_code(ghcb); 2452 2453 /* Only GHCB Usage code 0 is supported */ 2454 if (ghcb->ghcb_usage) { 2455 reason = GHCB_ERR_INVALID_USAGE; 2456 goto vmgexit_err; 2457 } 2458 2459 reason = GHCB_ERR_MISSING_INPUT; 2460 2461 if (!ghcb_sw_exit_code_is_valid(ghcb) || 2462 !ghcb_sw_exit_info_1_is_valid(ghcb) || 2463 !ghcb_sw_exit_info_2_is_valid(ghcb)) 2464 goto vmgexit_err; 2465 2466 switch (ghcb_get_sw_exit_code(ghcb)) { 2467 case SVM_EXIT_READ_DR7: 2468 break; 2469 case SVM_EXIT_WRITE_DR7: 2470 if (!ghcb_rax_is_valid(ghcb)) 2471 goto vmgexit_err; 2472 break; 2473 case SVM_EXIT_RDTSC: 2474 break; 2475 case SVM_EXIT_RDPMC: 2476 if (!ghcb_rcx_is_valid(ghcb)) 2477 goto vmgexit_err; 2478 break; 2479 case SVM_EXIT_CPUID: 2480 if (!ghcb_rax_is_valid(ghcb) || 2481 !ghcb_rcx_is_valid(ghcb)) 2482 goto vmgexit_err; 2483 if (ghcb_get_rax(ghcb) == 0xd) 2484 if (!ghcb_xcr0_is_valid(ghcb)) 2485 goto vmgexit_err; 2486 break; 2487 case SVM_EXIT_INVD: 2488 break; 2489 case SVM_EXIT_IOIO: 2490 if (ghcb_get_sw_exit_info_1(ghcb) & SVM_IOIO_STR_MASK) { 2491 if (!ghcb_sw_scratch_is_valid(ghcb)) 2492 goto vmgexit_err; 2493 } else { 2494 if (!(ghcb_get_sw_exit_info_1(ghcb) & SVM_IOIO_TYPE_MASK)) 2495 if (!ghcb_rax_is_valid(ghcb)) 2496 goto vmgexit_err; 2497 } 2498 break; 2499 case SVM_EXIT_MSR: 2500 if (!ghcb_rcx_is_valid(ghcb)) 2501 goto vmgexit_err; 2502 if (ghcb_get_sw_exit_info_1(ghcb)) { 2503 if (!ghcb_rax_is_valid(ghcb) || 2504 !ghcb_rdx_is_valid(ghcb)) 2505 goto vmgexit_err; 2506 } 2507 break; 2508 case SVM_EXIT_VMMCALL: 2509 if (!ghcb_rax_is_valid(ghcb) || 2510 !ghcb_cpl_is_valid(ghcb)) 2511 goto vmgexit_err; 2512 break; 2513 case SVM_EXIT_RDTSCP: 2514 break; 2515 case SVM_EXIT_WBINVD: 2516 break; 2517 case SVM_EXIT_MONITOR: 2518 if (!ghcb_rax_is_valid(ghcb) || 2519 !ghcb_rcx_is_valid(ghcb) || 2520 !ghcb_rdx_is_valid(ghcb)) 2521 goto vmgexit_err; 2522 break; 2523 case SVM_EXIT_MWAIT: 2524 if (!ghcb_rax_is_valid(ghcb) || 2525 !ghcb_rcx_is_valid(ghcb)) 2526 goto vmgexit_err; 2527 break; 2528 case SVM_VMGEXIT_MMIO_READ: 2529 case SVM_VMGEXIT_MMIO_WRITE: 2530 if (!ghcb_sw_scratch_is_valid(ghcb)) 2531 goto vmgexit_err; 2532 break; 2533 case SVM_VMGEXIT_NMI_COMPLETE: 2534 case SVM_VMGEXIT_AP_HLT_LOOP: 2535 case SVM_VMGEXIT_AP_JUMP_TABLE: 2536 case SVM_VMGEXIT_UNSUPPORTED_EVENT: 2537 break; 2538 default: 2539 reason = GHCB_ERR_INVALID_EVENT; 2540 goto vmgexit_err; 2541 } 2542 2543 return 0; 2544 2545 vmgexit_err: 2546 vcpu = &svm->vcpu; 2547 2548 if (reason == GHCB_ERR_INVALID_USAGE) { 2549 vcpu_unimpl(vcpu, "vmgexit: ghcb usage %#x is not valid\n", 2550 ghcb->ghcb_usage); 2551 } else if (reason == GHCB_ERR_INVALID_EVENT) { 2552 vcpu_unimpl(vcpu, "vmgexit: exit code %#llx is not valid\n", 2553 exit_code); 2554 } else { 2555 vcpu_unimpl(vcpu, "vmgexit: exit code %#llx input is not valid\n", 2556 exit_code); 2557 dump_ghcb(svm); 2558 } 2559 2560 /* Clear the valid entries fields */ 2561 memset(ghcb->save.valid_bitmap, 0, sizeof(ghcb->save.valid_bitmap)); 2562 2563 ghcb_set_sw_exit_info_1(ghcb, 2); 2564 ghcb_set_sw_exit_info_2(ghcb, reason); 2565 2566 /* Resume the guest to "return" the error code. */ 2567 return 1; 2568 } 2569 2570 void sev_es_unmap_ghcb(struct vcpu_svm *svm) 2571 { 2572 if (!svm->sev_es.ghcb) 2573 return; 2574 2575 if (svm->sev_es.ghcb_sa_free) { 2576 /* 2577 * The scratch area lives outside the GHCB, so there is a 2578 * buffer that, depending on the operation performed, may 2579 * need to be synced, then freed. 2580 */ 2581 if (svm->sev_es.ghcb_sa_sync) { 2582 kvm_write_guest(svm->vcpu.kvm, 2583 ghcb_get_sw_scratch(svm->sev_es.ghcb), 2584 svm->sev_es.ghcb_sa, 2585 svm->sev_es.ghcb_sa_len); 2586 svm->sev_es.ghcb_sa_sync = false; 2587 } 2588 2589 kvfree(svm->sev_es.ghcb_sa); 2590 svm->sev_es.ghcb_sa = NULL; 2591 svm->sev_es.ghcb_sa_free = false; 2592 } 2593 2594 trace_kvm_vmgexit_exit(svm->vcpu.vcpu_id, svm->sev_es.ghcb); 2595 2596 sev_es_sync_to_ghcb(svm); 2597 2598 kvm_vcpu_unmap(&svm->vcpu, &svm->sev_es.ghcb_map, true); 2599 svm->sev_es.ghcb = NULL; 2600 } 2601 2602 void pre_sev_run(struct vcpu_svm *svm, int cpu) 2603 { 2604 struct svm_cpu_data *sd = per_cpu_ptr(&svm_data, cpu); 2605 int asid = sev_get_asid(svm->vcpu.kvm); 2606 2607 /* Assign the asid allocated with this SEV guest */ 2608 svm->asid = asid; 2609 2610 /* 2611 * Flush guest TLB: 2612 * 2613 * 1) when different VMCB for the same ASID is to be run on the same host CPU. 2614 * 2) or this VMCB was executed on different host CPU in previous VMRUNs. 2615 */ 2616 if (sd->sev_vmcbs[asid] == svm->vmcb && 2617 svm->vcpu.arch.last_vmentry_cpu == cpu) 2618 return; 2619 2620 sd->sev_vmcbs[asid] = svm->vmcb; 2621 svm->vmcb->control.tlb_ctl = TLB_CONTROL_FLUSH_ASID; 2622 vmcb_mark_dirty(svm->vmcb, VMCB_ASID); 2623 } 2624 2625 #define GHCB_SCRATCH_AREA_LIMIT (16ULL * PAGE_SIZE) 2626 static int setup_vmgexit_scratch(struct vcpu_svm *svm, bool sync, u64 len) 2627 { 2628 struct vmcb_control_area *control = &svm->vmcb->control; 2629 struct ghcb *ghcb = svm->sev_es.ghcb; 2630 u64 ghcb_scratch_beg, ghcb_scratch_end; 2631 u64 scratch_gpa_beg, scratch_gpa_end; 2632 void *scratch_va; 2633 2634 scratch_gpa_beg = ghcb_get_sw_scratch(ghcb); 2635 if (!scratch_gpa_beg) { 2636 pr_err("vmgexit: scratch gpa not provided\n"); 2637 goto e_scratch; 2638 } 2639 2640 scratch_gpa_end = scratch_gpa_beg + len; 2641 if (scratch_gpa_end < scratch_gpa_beg) { 2642 pr_err("vmgexit: scratch length (%#llx) not valid for scratch address (%#llx)\n", 2643 len, scratch_gpa_beg); 2644 goto e_scratch; 2645 } 2646 2647 if ((scratch_gpa_beg & PAGE_MASK) == control->ghcb_gpa) { 2648 /* Scratch area begins within GHCB */ 2649 ghcb_scratch_beg = control->ghcb_gpa + 2650 offsetof(struct ghcb, shared_buffer); 2651 ghcb_scratch_end = control->ghcb_gpa + 2652 offsetof(struct ghcb, reserved_0xff0); 2653 2654 /* 2655 * If the scratch area begins within the GHCB, it must be 2656 * completely contained in the GHCB shared buffer area. 2657 */ 2658 if (scratch_gpa_beg < ghcb_scratch_beg || 2659 scratch_gpa_end > ghcb_scratch_end) { 2660 pr_err("vmgexit: scratch area is outside of GHCB shared buffer area (%#llx - %#llx)\n", 2661 scratch_gpa_beg, scratch_gpa_end); 2662 goto e_scratch; 2663 } 2664 2665 scratch_va = (void *)svm->sev_es.ghcb; 2666 scratch_va += (scratch_gpa_beg - control->ghcb_gpa); 2667 } else { 2668 /* 2669 * The guest memory must be read into a kernel buffer, so 2670 * limit the size 2671 */ 2672 if (len > GHCB_SCRATCH_AREA_LIMIT) { 2673 pr_err("vmgexit: scratch area exceeds KVM limits (%#llx requested, %#llx limit)\n", 2674 len, GHCB_SCRATCH_AREA_LIMIT); 2675 goto e_scratch; 2676 } 2677 scratch_va = kvzalloc(len, GFP_KERNEL_ACCOUNT); 2678 if (!scratch_va) 2679 return -ENOMEM; 2680 2681 if (kvm_read_guest(svm->vcpu.kvm, scratch_gpa_beg, scratch_va, len)) { 2682 /* Unable to copy scratch area from guest */ 2683 pr_err("vmgexit: kvm_read_guest for scratch area failed\n"); 2684 2685 kvfree(scratch_va); 2686 return -EFAULT; 2687 } 2688 2689 /* 2690 * The scratch area is outside the GHCB. The operation will 2691 * dictate whether the buffer needs to be synced before running 2692 * the vCPU next time (i.e. a read was requested so the data 2693 * must be written back to the guest memory). 2694 */ 2695 svm->sev_es.ghcb_sa_sync = sync; 2696 svm->sev_es.ghcb_sa_free = true; 2697 } 2698 2699 svm->sev_es.ghcb_sa = scratch_va; 2700 svm->sev_es.ghcb_sa_len = len; 2701 2702 return 0; 2703 2704 e_scratch: 2705 ghcb_set_sw_exit_info_1(ghcb, 2); 2706 ghcb_set_sw_exit_info_2(ghcb, GHCB_ERR_INVALID_SCRATCH_AREA); 2707 2708 return 1; 2709 } 2710 2711 static void set_ghcb_msr_bits(struct vcpu_svm *svm, u64 value, u64 mask, 2712 unsigned int pos) 2713 { 2714 svm->vmcb->control.ghcb_gpa &= ~(mask << pos); 2715 svm->vmcb->control.ghcb_gpa |= (value & mask) << pos; 2716 } 2717 2718 static u64 get_ghcb_msr_bits(struct vcpu_svm *svm, u64 mask, unsigned int pos) 2719 { 2720 return (svm->vmcb->control.ghcb_gpa >> pos) & mask; 2721 } 2722 2723 static void set_ghcb_msr(struct vcpu_svm *svm, u64 value) 2724 { 2725 svm->vmcb->control.ghcb_gpa = value; 2726 } 2727 2728 static int sev_handle_vmgexit_msr_protocol(struct vcpu_svm *svm) 2729 { 2730 struct vmcb_control_area *control = &svm->vmcb->control; 2731 struct kvm_vcpu *vcpu = &svm->vcpu; 2732 u64 ghcb_info; 2733 int ret = 1; 2734 2735 ghcb_info = control->ghcb_gpa & GHCB_MSR_INFO_MASK; 2736 2737 trace_kvm_vmgexit_msr_protocol_enter(svm->vcpu.vcpu_id, 2738 control->ghcb_gpa); 2739 2740 switch (ghcb_info) { 2741 case GHCB_MSR_SEV_INFO_REQ: 2742 set_ghcb_msr(svm, GHCB_MSR_SEV_INFO(GHCB_VERSION_MAX, 2743 GHCB_VERSION_MIN, 2744 sev_enc_bit)); 2745 break; 2746 case GHCB_MSR_CPUID_REQ: { 2747 u64 cpuid_fn, cpuid_reg, cpuid_value; 2748 2749 cpuid_fn = get_ghcb_msr_bits(svm, 2750 GHCB_MSR_CPUID_FUNC_MASK, 2751 GHCB_MSR_CPUID_FUNC_POS); 2752 2753 /* Initialize the registers needed by the CPUID intercept */ 2754 vcpu->arch.regs[VCPU_REGS_RAX] = cpuid_fn; 2755 vcpu->arch.regs[VCPU_REGS_RCX] = 0; 2756 2757 ret = svm_invoke_exit_handler(vcpu, SVM_EXIT_CPUID); 2758 if (!ret) { 2759 /* Error, keep GHCB MSR value as-is */ 2760 break; 2761 } 2762 2763 cpuid_reg = get_ghcb_msr_bits(svm, 2764 GHCB_MSR_CPUID_REG_MASK, 2765 GHCB_MSR_CPUID_REG_POS); 2766 if (cpuid_reg == 0) 2767 cpuid_value = vcpu->arch.regs[VCPU_REGS_RAX]; 2768 else if (cpuid_reg == 1) 2769 cpuid_value = vcpu->arch.regs[VCPU_REGS_RBX]; 2770 else if (cpuid_reg == 2) 2771 cpuid_value = vcpu->arch.regs[VCPU_REGS_RCX]; 2772 else 2773 cpuid_value = vcpu->arch.regs[VCPU_REGS_RDX]; 2774 2775 set_ghcb_msr_bits(svm, cpuid_value, 2776 GHCB_MSR_CPUID_VALUE_MASK, 2777 GHCB_MSR_CPUID_VALUE_POS); 2778 2779 set_ghcb_msr_bits(svm, GHCB_MSR_CPUID_RESP, 2780 GHCB_MSR_INFO_MASK, 2781 GHCB_MSR_INFO_POS); 2782 break; 2783 } 2784 case GHCB_MSR_TERM_REQ: { 2785 u64 reason_set, reason_code; 2786 2787 reason_set = get_ghcb_msr_bits(svm, 2788 GHCB_MSR_TERM_REASON_SET_MASK, 2789 GHCB_MSR_TERM_REASON_SET_POS); 2790 reason_code = get_ghcb_msr_bits(svm, 2791 GHCB_MSR_TERM_REASON_MASK, 2792 GHCB_MSR_TERM_REASON_POS); 2793 pr_info("SEV-ES guest requested termination: %#llx:%#llx\n", 2794 reason_set, reason_code); 2795 2796 vcpu->run->exit_reason = KVM_EXIT_SYSTEM_EVENT; 2797 vcpu->run->system_event.type = KVM_SYSTEM_EVENT_SEV_TERM; 2798 vcpu->run->system_event.ndata = 1; 2799 vcpu->run->system_event.data[0] = control->ghcb_gpa; 2800 2801 return 0; 2802 } 2803 default: 2804 /* Error, keep GHCB MSR value as-is */ 2805 break; 2806 } 2807 2808 trace_kvm_vmgexit_msr_protocol_exit(svm->vcpu.vcpu_id, 2809 control->ghcb_gpa, ret); 2810 2811 return ret; 2812 } 2813 2814 int sev_handle_vmgexit(struct kvm_vcpu *vcpu) 2815 { 2816 struct vcpu_svm *svm = to_svm(vcpu); 2817 struct vmcb_control_area *control = &svm->vmcb->control; 2818 u64 ghcb_gpa, exit_code; 2819 struct ghcb *ghcb; 2820 int ret; 2821 2822 /* Validate the GHCB */ 2823 ghcb_gpa = control->ghcb_gpa; 2824 if (ghcb_gpa & GHCB_MSR_INFO_MASK) 2825 return sev_handle_vmgexit_msr_protocol(svm); 2826 2827 if (!ghcb_gpa) { 2828 vcpu_unimpl(vcpu, "vmgexit: GHCB gpa is not set\n"); 2829 2830 /* Without a GHCB, just return right back to the guest */ 2831 return 1; 2832 } 2833 2834 if (kvm_vcpu_map(vcpu, ghcb_gpa >> PAGE_SHIFT, &svm->sev_es.ghcb_map)) { 2835 /* Unable to map GHCB from guest */ 2836 vcpu_unimpl(vcpu, "vmgexit: error mapping GHCB [%#llx] from guest\n", 2837 ghcb_gpa); 2838 2839 /* Without a GHCB, just return right back to the guest */ 2840 return 1; 2841 } 2842 2843 svm->sev_es.ghcb = svm->sev_es.ghcb_map.hva; 2844 ghcb = svm->sev_es.ghcb_map.hva; 2845 2846 trace_kvm_vmgexit_enter(vcpu->vcpu_id, ghcb); 2847 2848 exit_code = ghcb_get_sw_exit_code(ghcb); 2849 2850 ret = sev_es_validate_vmgexit(svm); 2851 if (ret) 2852 return ret; 2853 2854 sev_es_sync_from_ghcb(svm); 2855 ghcb_set_sw_exit_info_1(ghcb, 0); 2856 ghcb_set_sw_exit_info_2(ghcb, 0); 2857 2858 switch (exit_code) { 2859 case SVM_VMGEXIT_MMIO_READ: 2860 ret = setup_vmgexit_scratch(svm, true, control->exit_info_2); 2861 if (ret) 2862 break; 2863 2864 ret = kvm_sev_es_mmio_read(vcpu, 2865 control->exit_info_1, 2866 control->exit_info_2, 2867 svm->sev_es.ghcb_sa); 2868 break; 2869 case SVM_VMGEXIT_MMIO_WRITE: 2870 ret = setup_vmgexit_scratch(svm, false, control->exit_info_2); 2871 if (ret) 2872 break; 2873 2874 ret = kvm_sev_es_mmio_write(vcpu, 2875 control->exit_info_1, 2876 control->exit_info_2, 2877 svm->sev_es.ghcb_sa); 2878 break; 2879 case SVM_VMGEXIT_NMI_COMPLETE: 2880 ret = svm_invoke_exit_handler(vcpu, SVM_EXIT_IRET); 2881 break; 2882 case SVM_VMGEXIT_AP_HLT_LOOP: 2883 ret = kvm_emulate_ap_reset_hold(vcpu); 2884 break; 2885 case SVM_VMGEXIT_AP_JUMP_TABLE: { 2886 struct kvm_sev_info *sev = &to_kvm_svm(vcpu->kvm)->sev_info; 2887 2888 switch (control->exit_info_1) { 2889 case 0: 2890 /* Set AP jump table address */ 2891 sev->ap_jump_table = control->exit_info_2; 2892 break; 2893 case 1: 2894 /* Get AP jump table address */ 2895 ghcb_set_sw_exit_info_2(ghcb, sev->ap_jump_table); 2896 break; 2897 default: 2898 pr_err("svm: vmgexit: unsupported AP jump table request - exit_info_1=%#llx\n", 2899 control->exit_info_1); 2900 ghcb_set_sw_exit_info_1(ghcb, 2); 2901 ghcb_set_sw_exit_info_2(ghcb, GHCB_ERR_INVALID_INPUT); 2902 } 2903 2904 ret = 1; 2905 break; 2906 } 2907 case SVM_VMGEXIT_UNSUPPORTED_EVENT: 2908 vcpu_unimpl(vcpu, 2909 "vmgexit: unsupported event - exit_info_1=%#llx, exit_info_2=%#llx\n", 2910 control->exit_info_1, control->exit_info_2); 2911 ret = -EINVAL; 2912 break; 2913 default: 2914 ret = svm_invoke_exit_handler(vcpu, exit_code); 2915 } 2916 2917 return ret; 2918 } 2919 2920 int sev_es_string_io(struct vcpu_svm *svm, int size, unsigned int port, int in) 2921 { 2922 int count; 2923 int bytes; 2924 int r; 2925 2926 if (svm->vmcb->control.exit_info_2 > INT_MAX) 2927 return -EINVAL; 2928 2929 count = svm->vmcb->control.exit_info_2; 2930 if (unlikely(check_mul_overflow(count, size, &bytes))) 2931 return -EINVAL; 2932 2933 r = setup_vmgexit_scratch(svm, in, bytes); 2934 if (r) 2935 return r; 2936 2937 return kvm_sev_es_string_io(&svm->vcpu, size, port, svm->sev_es.ghcb_sa, 2938 count, in); 2939 } 2940 2941 static void sev_es_init_vmcb(struct vcpu_svm *svm) 2942 { 2943 struct kvm_vcpu *vcpu = &svm->vcpu; 2944 2945 svm->vmcb->control.nested_ctl |= SVM_NESTED_CTL_SEV_ES_ENABLE; 2946 svm->vmcb->control.virt_ext |= LBR_CTL_ENABLE_MASK; 2947 2948 /* 2949 * An SEV-ES guest requires a VMSA area that is a separate from the 2950 * VMCB page. Do not include the encryption mask on the VMSA physical 2951 * address since hardware will access it using the guest key. 2952 */ 2953 svm->vmcb->control.vmsa_pa = __pa(svm->sev_es.vmsa); 2954 2955 /* Can't intercept CR register access, HV can't modify CR registers */ 2956 svm_clr_intercept(svm, INTERCEPT_CR0_READ); 2957 svm_clr_intercept(svm, INTERCEPT_CR4_READ); 2958 svm_clr_intercept(svm, INTERCEPT_CR8_READ); 2959 svm_clr_intercept(svm, INTERCEPT_CR0_WRITE); 2960 svm_clr_intercept(svm, INTERCEPT_CR4_WRITE); 2961 svm_clr_intercept(svm, INTERCEPT_CR8_WRITE); 2962 2963 svm_clr_intercept(svm, INTERCEPT_SELECTIVE_CR0); 2964 2965 /* Track EFER/CR register changes */ 2966 svm_set_intercept(svm, TRAP_EFER_WRITE); 2967 svm_set_intercept(svm, TRAP_CR0_WRITE); 2968 svm_set_intercept(svm, TRAP_CR4_WRITE); 2969 svm_set_intercept(svm, TRAP_CR8_WRITE); 2970 2971 /* No support for enable_vmware_backdoor */ 2972 clr_exception_intercept(svm, GP_VECTOR); 2973 2974 /* Can't intercept XSETBV, HV can't modify XCR0 directly */ 2975 svm_clr_intercept(svm, INTERCEPT_XSETBV); 2976 2977 /* Clear intercepts on selected MSRs */ 2978 set_msr_interception(vcpu, svm->msrpm, MSR_EFER, 1, 1); 2979 set_msr_interception(vcpu, svm->msrpm, MSR_IA32_CR_PAT, 1, 1); 2980 set_msr_interception(vcpu, svm->msrpm, MSR_IA32_LASTBRANCHFROMIP, 1, 1); 2981 set_msr_interception(vcpu, svm->msrpm, MSR_IA32_LASTBRANCHTOIP, 1, 1); 2982 set_msr_interception(vcpu, svm->msrpm, MSR_IA32_LASTINTFROMIP, 1, 1); 2983 set_msr_interception(vcpu, svm->msrpm, MSR_IA32_LASTINTTOIP, 1, 1); 2984 2985 if (boot_cpu_has(X86_FEATURE_V_TSC_AUX) && 2986 (guest_cpuid_has(&svm->vcpu, X86_FEATURE_RDTSCP) || 2987 guest_cpuid_has(&svm->vcpu, X86_FEATURE_RDPID))) { 2988 set_msr_interception(vcpu, svm->msrpm, MSR_TSC_AUX, 1, 1); 2989 if (guest_cpuid_has(&svm->vcpu, X86_FEATURE_RDTSCP)) 2990 svm_clr_intercept(svm, INTERCEPT_RDTSCP); 2991 } 2992 } 2993 2994 void sev_init_vmcb(struct vcpu_svm *svm) 2995 { 2996 svm->vmcb->control.nested_ctl |= SVM_NESTED_CTL_SEV_ENABLE; 2997 clr_exception_intercept(svm, UD_VECTOR); 2998 2999 if (sev_es_guest(svm->vcpu.kvm)) 3000 sev_es_init_vmcb(svm); 3001 } 3002 3003 void sev_es_vcpu_reset(struct vcpu_svm *svm) 3004 { 3005 /* 3006 * Set the GHCB MSR value as per the GHCB specification when emulating 3007 * vCPU RESET for an SEV-ES guest. 3008 */ 3009 set_ghcb_msr(svm, GHCB_MSR_SEV_INFO(GHCB_VERSION_MAX, 3010 GHCB_VERSION_MIN, 3011 sev_enc_bit)); 3012 } 3013 3014 void sev_es_prepare_switch_to_guest(struct sev_es_save_area *hostsa) 3015 { 3016 /* 3017 * As an SEV-ES guest, hardware will restore the host state on VMEXIT, 3018 * of which one step is to perform a VMLOAD. KVM performs the 3019 * corresponding VMSAVE in svm_prepare_guest_switch for both 3020 * traditional and SEV-ES guests. 3021 */ 3022 3023 /* XCR0 is restored on VMEXIT, save the current host value */ 3024 hostsa->xcr0 = xgetbv(XCR_XFEATURE_ENABLED_MASK); 3025 3026 /* PKRU is restored on VMEXIT, save the current host value */ 3027 hostsa->pkru = read_pkru(); 3028 3029 /* MSR_IA32_XSS is restored on VMEXIT, save the currnet host value */ 3030 hostsa->xss = host_xss; 3031 } 3032 3033 void sev_vcpu_deliver_sipi_vector(struct kvm_vcpu *vcpu, u8 vector) 3034 { 3035 struct vcpu_svm *svm = to_svm(vcpu); 3036 3037 /* First SIPI: Use the values as initially set by the VMM */ 3038 if (!svm->sev_es.received_first_sipi) { 3039 svm->sev_es.received_first_sipi = true; 3040 return; 3041 } 3042 3043 /* 3044 * Subsequent SIPI: Return from an AP Reset Hold VMGEXIT, where 3045 * the guest will set the CS and RIP. Set SW_EXIT_INFO_2 to a 3046 * non-zero value. 3047 */ 3048 if (!svm->sev_es.ghcb) 3049 return; 3050 3051 ghcb_set_sw_exit_info_2(svm->sev_es.ghcb, 1); 3052 } 3053