1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * AMD Secure Encrypted Virtualization (SEV) interface 4 * 5 * Copyright (C) 2016,2019 Advanced Micro Devices, Inc. 6 * 7 * Author: Brijesh Singh <brijesh.singh@amd.com> 8 */ 9 10 #include <linux/bitfield.h> 11 #include <linux/module.h> 12 #include <linux/kernel.h> 13 #include <linux/kthread.h> 14 #include <linux/sched.h> 15 #include <linux/interrupt.h> 16 #include <linux/spinlock.h> 17 #include <linux/spinlock_types.h> 18 #include <linux/types.h> 19 #include <linux/mutex.h> 20 #include <linux/delay.h> 21 #include <linux/hw_random.h> 22 #include <linux/ccp.h> 23 #include <linux/firmware.h> 24 #include <linux/panic_notifier.h> 25 #include <linux/gfp.h> 26 #include <linux/cpufeature.h> 27 #include <linux/fs.h> 28 #include <linux/fs_struct.h> 29 #include <linux/psp.h> 30 #include <linux/amd-iommu.h> 31 #include <linux/crash_dump.h> 32 33 #include <asm/smp.h> 34 #include <asm/cacheflush.h> 35 #include <asm/e820/types.h> 36 #include <asm/sev.h> 37 #include <asm/msr.h> 38 39 #include "psp-dev.h" 40 #include "sev-dev.h" 41 42 #define DEVICE_NAME "sev" 43 #define SEV_FW_FILE "amd/sev.fw" 44 #define SEV_FW_NAME_SIZE 64 45 46 /* Minimum firmware version required for the SEV-SNP support */ 47 #define SNP_MIN_API_MAJOR 1 48 #define SNP_MIN_API_MINOR 51 49 50 /* 51 * Maximum number of firmware-writable buffers that might be specified 52 * in the parameters of a legacy SEV command buffer. 53 */ 54 #define CMD_BUF_FW_WRITABLE_MAX 2 55 56 /* Leave room in the descriptor array for an end-of-list indicator. */ 57 #define CMD_BUF_DESC_MAX (CMD_BUF_FW_WRITABLE_MAX + 1) 58 59 static DEFINE_MUTEX(sev_cmd_mutex); 60 static struct sev_misc_dev *misc_dev; 61 62 static int psp_cmd_timeout = 100; 63 module_param(psp_cmd_timeout, int, 0644); 64 MODULE_PARM_DESC(psp_cmd_timeout, " default timeout value, in seconds, for PSP commands"); 65 66 static int psp_probe_timeout = 5; 67 module_param(psp_probe_timeout, int, 0644); 68 MODULE_PARM_DESC(psp_probe_timeout, " default timeout value, in seconds, during PSP device probe"); 69 70 static char *init_ex_path; 71 module_param(init_ex_path, charp, 0444); 72 MODULE_PARM_DESC(init_ex_path, " Path for INIT_EX data; if set try INIT_EX"); 73 74 static bool psp_init_on_probe = true; 75 module_param(psp_init_on_probe, bool, 0444); 76 MODULE_PARM_DESC(psp_init_on_probe, " if true, the PSP will be initialized on module init. Else the PSP will be initialized on the first command requiring it"); 77 78 #if IS_ENABLED(CONFIG_PCI_TSM) 79 static bool sev_tio_enabled = true; 80 module_param_named(tio, sev_tio_enabled, bool, 0444); 81 MODULE_PARM_DESC(tio, "Enables TIO in SNP_INIT_EX"); 82 #else 83 static const bool sev_tio_enabled = false; 84 #endif 85 86 MODULE_FIRMWARE("amd/amd_sev_fam17h_model0xh.sbin"); /* 1st gen EPYC */ 87 MODULE_FIRMWARE("amd/amd_sev_fam17h_model3xh.sbin"); /* 2nd gen EPYC */ 88 MODULE_FIRMWARE("amd/amd_sev_fam19h_model0xh.sbin"); /* 3rd gen EPYC */ 89 MODULE_FIRMWARE("amd/amd_sev_fam19h_model1xh.sbin"); /* 4th gen EPYC */ 90 91 static bool psp_dead; 92 static int psp_timeout; 93 94 enum snp_hv_fixed_pages_state { 95 ALLOCATED, 96 HV_FIXED, 97 }; 98 99 struct snp_hv_fixed_pages_entry { 100 struct list_head list; 101 struct page *page; 102 unsigned int order; 103 bool free; 104 enum snp_hv_fixed_pages_state page_state; 105 }; 106 107 static LIST_HEAD(snp_hv_fixed_pages); 108 109 /* Trusted Memory Region (TMR): 110 * The TMR is a 1MB area that must be 1MB aligned. Use the page allocator 111 * to allocate the memory, which will return aligned memory for the specified 112 * allocation order. 113 * 114 * When SEV-SNP is enabled the TMR needs to be 2MB aligned and 2MB sized. 115 */ 116 #define SEV_TMR_SIZE (1024 * 1024) 117 #define SNP_TMR_SIZE (2 * 1024 * 1024) 118 119 static void *sev_es_tmr; 120 static size_t sev_es_tmr_size = SEV_TMR_SIZE; 121 122 /* INIT_EX NV Storage: 123 * The NV Storage is a 32Kb area and must be 4Kb page aligned. Use the page 124 * allocator to allocate the memory, which will return aligned memory for the 125 * specified allocation order. 126 */ 127 #define NV_LENGTH (32 * 1024) 128 static void *sev_init_ex_buffer; 129 130 static void __sev_firmware_shutdown(struct sev_device *sev, bool panic); 131 132 static int snp_shutdown_on_panic(struct notifier_block *nb, 133 unsigned long reason, void *arg); 134 135 static struct notifier_block snp_panic_notifier = { 136 .notifier_call = snp_shutdown_on_panic, 137 }; 138 139 static inline bool sev_version_greater_or_equal(u8 maj, u8 min) 140 { 141 struct sev_device *sev = psp_master->sev_data; 142 143 if (sev->api_major > maj) 144 return true; 145 146 if (sev->api_major == maj && sev->api_minor >= min) 147 return true; 148 149 return false; 150 } 151 152 static void sev_irq_handler(int irq, void *data, unsigned int status) 153 { 154 struct sev_device *sev = data; 155 int reg; 156 157 /* Check if it is command completion: */ 158 if (!(status & SEV_CMD_COMPLETE)) 159 return; 160 161 /* Check if it is SEV command completion: */ 162 reg = ioread32(sev->io_regs + sev->vdata->cmdresp_reg); 163 if (FIELD_GET(PSP_CMDRESP_RESP, reg)) { 164 sev->int_rcvd = 1; 165 wake_up(&sev->int_queue); 166 } 167 } 168 169 static int sev_wait_cmd_ioc(struct sev_device *sev, 170 unsigned int *reg, unsigned int timeout) 171 { 172 int ret; 173 174 /* 175 * If invoked during panic handling, local interrupts are disabled, 176 * so the PSP command completion interrupt can't be used. Poll for 177 * PSP command completion instead. 178 */ 179 if (irqs_disabled()) { 180 unsigned long timeout_usecs = (timeout * USEC_PER_SEC) / 10; 181 182 /* Poll for SEV command completion: */ 183 while (timeout_usecs--) { 184 *reg = ioread32(sev->io_regs + sev->vdata->cmdresp_reg); 185 if (*reg & PSP_CMDRESP_RESP) 186 return 0; 187 188 udelay(10); 189 } 190 return -ETIMEDOUT; 191 } 192 193 ret = wait_event_timeout(sev->int_queue, 194 sev->int_rcvd, timeout * HZ); 195 if (!ret) 196 return -ETIMEDOUT; 197 198 *reg = ioread32(sev->io_regs + sev->vdata->cmdresp_reg); 199 200 return 0; 201 } 202 203 static int sev_cmd_buffer_len(int cmd) 204 { 205 switch (cmd) { 206 case SEV_CMD_INIT: return sizeof(struct sev_data_init); 207 case SEV_CMD_INIT_EX: return sizeof(struct sev_data_init_ex); 208 case SEV_CMD_SNP_SHUTDOWN_EX: return sizeof(struct sev_data_snp_shutdown_ex); 209 case SEV_CMD_SNP_INIT_EX: return sizeof(struct sev_data_snp_init_ex); 210 case SEV_CMD_PLATFORM_STATUS: return sizeof(struct sev_user_data_status); 211 case SEV_CMD_PEK_CSR: return sizeof(struct sev_data_pek_csr); 212 case SEV_CMD_PEK_CERT_IMPORT: return sizeof(struct sev_data_pek_cert_import); 213 case SEV_CMD_PDH_CERT_EXPORT: return sizeof(struct sev_data_pdh_cert_export); 214 case SEV_CMD_LAUNCH_START: return sizeof(struct sev_data_launch_start); 215 case SEV_CMD_LAUNCH_UPDATE_DATA: return sizeof(struct sev_data_launch_update_data); 216 case SEV_CMD_LAUNCH_UPDATE_VMSA: return sizeof(struct sev_data_launch_update_vmsa); 217 case SEV_CMD_LAUNCH_FINISH: return sizeof(struct sev_data_launch_finish); 218 case SEV_CMD_LAUNCH_MEASURE: return sizeof(struct sev_data_launch_measure); 219 case SEV_CMD_ACTIVATE: return sizeof(struct sev_data_activate); 220 case SEV_CMD_DEACTIVATE: return sizeof(struct sev_data_deactivate); 221 case SEV_CMD_DECOMMISSION: return sizeof(struct sev_data_decommission); 222 case SEV_CMD_GUEST_STATUS: return sizeof(struct sev_data_guest_status); 223 case SEV_CMD_DBG_DECRYPT: return sizeof(struct sev_data_dbg); 224 case SEV_CMD_DBG_ENCRYPT: return sizeof(struct sev_data_dbg); 225 case SEV_CMD_SEND_START: return sizeof(struct sev_data_send_start); 226 case SEV_CMD_SEND_UPDATE_DATA: return sizeof(struct sev_data_send_update_data); 227 case SEV_CMD_SEND_UPDATE_VMSA: return sizeof(struct sev_data_send_update_vmsa); 228 case SEV_CMD_SEND_FINISH: return sizeof(struct sev_data_send_finish); 229 case SEV_CMD_RECEIVE_START: return sizeof(struct sev_data_receive_start); 230 case SEV_CMD_RECEIVE_FINISH: return sizeof(struct sev_data_receive_finish); 231 case SEV_CMD_RECEIVE_UPDATE_DATA: return sizeof(struct sev_data_receive_update_data); 232 case SEV_CMD_RECEIVE_UPDATE_VMSA: return sizeof(struct sev_data_receive_update_vmsa); 233 case SEV_CMD_LAUNCH_UPDATE_SECRET: return sizeof(struct sev_data_launch_secret); 234 case SEV_CMD_DOWNLOAD_FIRMWARE: return sizeof(struct sev_data_download_firmware); 235 case SEV_CMD_GET_ID: return sizeof(struct sev_data_get_id); 236 case SEV_CMD_ATTESTATION_REPORT: return sizeof(struct sev_data_attestation_report); 237 case SEV_CMD_SEND_CANCEL: return sizeof(struct sev_data_send_cancel); 238 case SEV_CMD_SNP_GCTX_CREATE: return sizeof(struct sev_data_snp_addr); 239 case SEV_CMD_SNP_LAUNCH_START: return sizeof(struct sev_data_snp_launch_start); 240 case SEV_CMD_SNP_LAUNCH_UPDATE: return sizeof(struct sev_data_snp_launch_update); 241 case SEV_CMD_SNP_ACTIVATE: return sizeof(struct sev_data_snp_activate); 242 case SEV_CMD_SNP_DECOMMISSION: return sizeof(struct sev_data_snp_addr); 243 case SEV_CMD_SNP_PAGE_RECLAIM: return sizeof(struct sev_data_snp_page_reclaim); 244 case SEV_CMD_SNP_GUEST_STATUS: return sizeof(struct sev_data_snp_guest_status); 245 case SEV_CMD_SNP_LAUNCH_FINISH: return sizeof(struct sev_data_snp_launch_finish); 246 case SEV_CMD_SNP_DBG_DECRYPT: return sizeof(struct sev_data_snp_dbg); 247 case SEV_CMD_SNP_DBG_ENCRYPT: return sizeof(struct sev_data_snp_dbg); 248 case SEV_CMD_SNP_VERIFY_MITIGATION: return sizeof(struct sev_data_snp_verify_mitigation); 249 case SEV_CMD_SNP_PAGE_UNSMASH: return sizeof(struct sev_data_snp_page_unsmash); 250 case SEV_CMD_SNP_PLATFORM_STATUS: return sizeof(struct sev_data_snp_addr); 251 case SEV_CMD_SNP_GUEST_REQUEST: return sizeof(struct sev_data_snp_guest_request); 252 case SEV_CMD_SNP_CONFIG: return sizeof(struct sev_user_data_snp_config); 253 case SEV_CMD_SNP_COMMIT: return sizeof(struct sev_data_snp_commit); 254 case SEV_CMD_SNP_FEATURE_INFO: return sizeof(struct sev_data_snp_feature_info); 255 case SEV_CMD_SNP_VLEK_LOAD: return sizeof(struct sev_user_data_snp_vlek_load); 256 default: return sev_tio_cmd_buffer_len(cmd); 257 } 258 259 return 0; 260 } 261 262 static struct file *open_file_as_root(const char *filename, int flags, umode_t mode) 263 { 264 struct path root __free(path_put) = {}; 265 266 task_lock(&init_task); 267 get_fs_root(init_task.fs, &root); 268 task_unlock(&init_task); 269 270 CLASS(prepare_creds, cred)(); 271 if (!cred) 272 return ERR_PTR(-ENOMEM); 273 274 cred->fsuid = GLOBAL_ROOT_UID; 275 276 scoped_with_creds(cred) 277 return file_open_root(&root, filename, flags, mode); 278 } 279 280 static int sev_read_init_ex_file(void) 281 { 282 struct sev_device *sev = psp_master->sev_data; 283 struct file *fp; 284 ssize_t nread; 285 286 lockdep_assert_held(&sev_cmd_mutex); 287 288 if (!sev_init_ex_buffer) 289 return -EOPNOTSUPP; 290 291 fp = open_file_as_root(init_ex_path, O_RDONLY, 0); 292 if (IS_ERR(fp)) { 293 int ret = PTR_ERR(fp); 294 295 if (ret == -ENOENT) { 296 dev_info(sev->dev, 297 "SEV: %s does not exist and will be created later.\n", 298 init_ex_path); 299 ret = 0; 300 } else { 301 dev_err(sev->dev, 302 "SEV: could not open %s for read, error %d\n", 303 init_ex_path, ret); 304 } 305 return ret; 306 } 307 308 nread = kernel_read(fp, sev_init_ex_buffer, NV_LENGTH, NULL); 309 if (nread != NV_LENGTH) { 310 dev_info(sev->dev, 311 "SEV: could not read %u bytes to non volatile memory area, ret %ld\n", 312 NV_LENGTH, nread); 313 } 314 315 dev_dbg(sev->dev, "SEV: read %ld bytes from NV file\n", nread); 316 filp_close(fp, NULL); 317 318 return 0; 319 } 320 321 static int sev_write_init_ex_file(void) 322 { 323 struct sev_device *sev = psp_master->sev_data; 324 struct file *fp; 325 loff_t offset = 0; 326 ssize_t nwrite; 327 328 lockdep_assert_held(&sev_cmd_mutex); 329 330 if (!sev_init_ex_buffer) 331 return 0; 332 333 fp = open_file_as_root(init_ex_path, O_CREAT | O_WRONLY, 0600); 334 if (IS_ERR(fp)) { 335 int ret = PTR_ERR(fp); 336 337 dev_err(sev->dev, 338 "SEV: could not open file for write, error %d\n", 339 ret); 340 return ret; 341 } 342 343 nwrite = kernel_write(fp, sev_init_ex_buffer, NV_LENGTH, &offset); 344 vfs_fsync(fp, 0); 345 filp_close(fp, NULL); 346 347 if (nwrite != NV_LENGTH) { 348 dev_err(sev->dev, 349 "SEV: failed to write %u bytes to non volatile memory area, ret %ld\n", 350 NV_LENGTH, nwrite); 351 return -EIO; 352 } 353 354 dev_dbg(sev->dev, "SEV: write successful to NV file\n"); 355 356 return 0; 357 } 358 359 static int sev_write_init_ex_file_if_required(int cmd_id) 360 { 361 lockdep_assert_held(&sev_cmd_mutex); 362 363 if (!sev_init_ex_buffer) 364 return 0; 365 366 /* 367 * Only a few platform commands modify the SPI/NV area, but none of the 368 * non-platform commands do. Only INIT(_EX), PLATFORM_RESET, PEK_GEN, 369 * PEK_CERT_IMPORT, and PDH_GEN do. 370 */ 371 switch (cmd_id) { 372 case SEV_CMD_FACTORY_RESET: 373 case SEV_CMD_INIT_EX: 374 case SEV_CMD_PDH_GEN: 375 case SEV_CMD_PEK_CERT_IMPORT: 376 case SEV_CMD_PEK_GEN: 377 break; 378 default: 379 return 0; 380 } 381 382 return sev_write_init_ex_file(); 383 } 384 385 int snp_reclaim_pages(unsigned long paddr, unsigned int npages, bool locked) 386 { 387 int ret, err, i; 388 389 paddr = __sme_clr(ALIGN_DOWN(paddr, PAGE_SIZE)); 390 391 for (i = 0; i < npages; i++, paddr += PAGE_SIZE) { 392 struct sev_data_snp_page_reclaim data = {0}; 393 394 data.paddr = paddr; 395 396 if (locked) 397 ret = __sev_do_cmd_locked(SEV_CMD_SNP_PAGE_RECLAIM, &data, &err); 398 else 399 ret = sev_do_cmd(SEV_CMD_SNP_PAGE_RECLAIM, &data, &err); 400 401 if (ret) 402 goto cleanup; 403 404 ret = rmp_make_shared(__phys_to_pfn(paddr), PG_LEVEL_4K); 405 if (ret) 406 goto cleanup; 407 } 408 409 return 0; 410 411 cleanup: 412 /* 413 * If there was a failure reclaiming the page then it is no longer safe 414 * to release it back to the system; leak it instead. 415 */ 416 snp_leak_pages(__phys_to_pfn(paddr), npages - i); 417 return ret; 418 } 419 EXPORT_SYMBOL_GPL(snp_reclaim_pages); 420 421 static int rmp_mark_pages_firmware(unsigned long paddr, unsigned int npages, bool locked) 422 { 423 unsigned long pfn = __sme_clr(paddr) >> PAGE_SHIFT; 424 int rc, i; 425 426 for (i = 0; i < npages; i++, pfn++) { 427 rc = rmp_make_private(pfn, 0, PG_LEVEL_4K, 0, true); 428 if (rc) 429 goto cleanup; 430 } 431 432 return 0; 433 434 cleanup: 435 /* 436 * Try unrolling the firmware state changes by 437 * reclaiming the pages which were already changed to the 438 * firmware state. 439 */ 440 snp_reclaim_pages(paddr, i, locked); 441 442 return rc; 443 } 444 445 static struct page *__snp_alloc_firmware_pages(gfp_t gfp_mask, int order, bool locked) 446 { 447 unsigned long npages = 1ul << order, paddr; 448 struct sev_device *sev; 449 struct page *page; 450 451 if (!psp_master || !psp_master->sev_data) 452 return NULL; 453 454 page = alloc_pages(gfp_mask, order); 455 if (!page) 456 return NULL; 457 458 /* If SEV-SNP is initialized then add the page in RMP table. */ 459 sev = psp_master->sev_data; 460 if (!sev->snp_initialized) 461 return page; 462 463 paddr = __pa((unsigned long)page_address(page)); 464 if (rmp_mark_pages_firmware(paddr, npages, locked)) 465 return NULL; 466 467 return page; 468 } 469 470 void *snp_alloc_firmware_page(gfp_t gfp_mask) 471 { 472 struct page *page; 473 474 page = __snp_alloc_firmware_pages(gfp_mask, 0, false); 475 476 return page ? page_address(page) : NULL; 477 } 478 EXPORT_SYMBOL_GPL(snp_alloc_firmware_page); 479 480 static void __snp_free_firmware_pages(struct page *page, int order, bool locked) 481 { 482 struct sev_device *sev = psp_master->sev_data; 483 unsigned long paddr, npages = 1ul << order; 484 485 if (!page) 486 return; 487 488 paddr = __pa((unsigned long)page_address(page)); 489 if (sev->snp_initialized && 490 snp_reclaim_pages(paddr, npages, locked)) 491 return; 492 493 __free_pages(page, order); 494 } 495 496 void snp_free_firmware_page(void *addr) 497 { 498 if (!addr) 499 return; 500 501 __snp_free_firmware_pages(virt_to_page(addr), 0, false); 502 } 503 EXPORT_SYMBOL_GPL(snp_free_firmware_page); 504 505 static void *sev_fw_alloc(unsigned long len) 506 { 507 struct page *page; 508 509 page = __snp_alloc_firmware_pages(GFP_KERNEL, get_order(len), true); 510 if (!page) 511 return NULL; 512 513 return page_address(page); 514 } 515 516 /** 517 * struct cmd_buf_desc - descriptors for managing legacy SEV command address 518 * parameters corresponding to buffers that may be written to by firmware. 519 * 520 * @paddr_ptr: pointer to the address parameter in the command buffer which may 521 * need to be saved/restored depending on whether a bounce buffer 522 * is used. In the case of a bounce buffer, the command buffer 523 * needs to be updated with the address of the new bounce buffer 524 * snp_map_cmd_buf_desc() has allocated specifically for it. Must 525 * be NULL if this descriptor is only an end-of-list indicator. 526 * 527 * @paddr_orig: storage for the original address parameter, which can be used to 528 * restore the original value in @paddr_ptr in cases where it is 529 * replaced with the address of a bounce buffer. 530 * 531 * @len: length of buffer located at the address originally stored at @paddr_ptr 532 * 533 * @guest_owned: true if the address corresponds to guest-owned pages, in which 534 * case bounce buffers are not needed. 535 */ 536 struct cmd_buf_desc { 537 u64 *paddr_ptr; 538 u64 paddr_orig; 539 u32 len; 540 bool guest_owned; 541 }; 542 543 /* 544 * If a legacy SEV command parameter is a memory address, those pages in 545 * turn need to be transitioned to/from firmware-owned before/after 546 * executing the firmware command. 547 * 548 * Additionally, in cases where those pages are not guest-owned, a bounce 549 * buffer is needed in place of the original memory address parameter. 550 * 551 * A set of descriptors are used to keep track of this handling, and 552 * initialized here based on the specific commands being executed. 553 */ 554 static void snp_populate_cmd_buf_desc_list(int cmd, void *cmd_buf, 555 struct cmd_buf_desc *desc_list) 556 { 557 switch (cmd) { 558 case SEV_CMD_PDH_CERT_EXPORT: { 559 struct sev_data_pdh_cert_export *data = cmd_buf; 560 561 desc_list[0].paddr_ptr = &data->pdh_cert_address; 562 desc_list[0].len = data->pdh_cert_len; 563 desc_list[1].paddr_ptr = &data->cert_chain_address; 564 desc_list[1].len = data->cert_chain_len; 565 break; 566 } 567 case SEV_CMD_GET_ID: { 568 struct sev_data_get_id *data = cmd_buf; 569 570 desc_list[0].paddr_ptr = &data->address; 571 desc_list[0].len = data->len; 572 break; 573 } 574 case SEV_CMD_PEK_CSR: { 575 struct sev_data_pek_csr *data = cmd_buf; 576 577 desc_list[0].paddr_ptr = &data->address; 578 desc_list[0].len = data->len; 579 break; 580 } 581 case SEV_CMD_LAUNCH_UPDATE_DATA: { 582 struct sev_data_launch_update_data *data = cmd_buf; 583 584 desc_list[0].paddr_ptr = &data->address; 585 desc_list[0].len = data->len; 586 desc_list[0].guest_owned = true; 587 break; 588 } 589 case SEV_CMD_LAUNCH_UPDATE_VMSA: { 590 struct sev_data_launch_update_vmsa *data = cmd_buf; 591 592 desc_list[0].paddr_ptr = &data->address; 593 desc_list[0].len = data->len; 594 desc_list[0].guest_owned = true; 595 break; 596 } 597 case SEV_CMD_LAUNCH_MEASURE: { 598 struct sev_data_launch_measure *data = cmd_buf; 599 600 desc_list[0].paddr_ptr = &data->address; 601 desc_list[0].len = data->len; 602 break; 603 } 604 case SEV_CMD_LAUNCH_UPDATE_SECRET: { 605 struct sev_data_launch_secret *data = cmd_buf; 606 607 desc_list[0].paddr_ptr = &data->guest_address; 608 desc_list[0].len = data->guest_len; 609 desc_list[0].guest_owned = true; 610 break; 611 } 612 case SEV_CMD_DBG_DECRYPT: { 613 struct sev_data_dbg *data = cmd_buf; 614 615 desc_list[0].paddr_ptr = &data->dst_addr; 616 desc_list[0].len = data->len; 617 desc_list[0].guest_owned = true; 618 break; 619 } 620 case SEV_CMD_DBG_ENCRYPT: { 621 struct sev_data_dbg *data = cmd_buf; 622 623 desc_list[0].paddr_ptr = &data->dst_addr; 624 desc_list[0].len = data->len; 625 desc_list[0].guest_owned = true; 626 break; 627 } 628 case SEV_CMD_ATTESTATION_REPORT: { 629 struct sev_data_attestation_report *data = cmd_buf; 630 631 desc_list[0].paddr_ptr = &data->address; 632 desc_list[0].len = data->len; 633 break; 634 } 635 case SEV_CMD_SEND_START: { 636 struct sev_data_send_start *data = cmd_buf; 637 638 desc_list[0].paddr_ptr = &data->session_address; 639 desc_list[0].len = data->session_len; 640 break; 641 } 642 case SEV_CMD_SEND_UPDATE_DATA: { 643 struct sev_data_send_update_data *data = cmd_buf; 644 645 desc_list[0].paddr_ptr = &data->hdr_address; 646 desc_list[0].len = data->hdr_len; 647 desc_list[1].paddr_ptr = &data->trans_address; 648 desc_list[1].len = data->trans_len; 649 break; 650 } 651 case SEV_CMD_SEND_UPDATE_VMSA: { 652 struct sev_data_send_update_vmsa *data = cmd_buf; 653 654 desc_list[0].paddr_ptr = &data->hdr_address; 655 desc_list[0].len = data->hdr_len; 656 desc_list[1].paddr_ptr = &data->trans_address; 657 desc_list[1].len = data->trans_len; 658 break; 659 } 660 case SEV_CMD_RECEIVE_UPDATE_DATA: { 661 struct sev_data_receive_update_data *data = cmd_buf; 662 663 desc_list[0].paddr_ptr = &data->guest_address; 664 desc_list[0].len = data->guest_len; 665 desc_list[0].guest_owned = true; 666 break; 667 } 668 case SEV_CMD_RECEIVE_UPDATE_VMSA: { 669 struct sev_data_receive_update_vmsa *data = cmd_buf; 670 671 desc_list[0].paddr_ptr = &data->guest_address; 672 desc_list[0].len = data->guest_len; 673 desc_list[0].guest_owned = true; 674 break; 675 } 676 default: 677 break; 678 } 679 } 680 681 static int snp_map_cmd_buf_desc(struct cmd_buf_desc *desc) 682 { 683 unsigned int npages; 684 685 if (!desc->len) 686 return 0; 687 688 /* Allocate a bounce buffer if this isn't a guest owned page. */ 689 if (!desc->guest_owned) { 690 struct page *page; 691 692 page = alloc_pages(GFP_KERNEL_ACCOUNT, get_order(desc->len)); 693 if (!page) { 694 pr_warn("Failed to allocate bounce buffer for SEV legacy command.\n"); 695 return -ENOMEM; 696 } 697 698 desc->paddr_orig = *desc->paddr_ptr; 699 *desc->paddr_ptr = __psp_pa(page_to_virt(page)); 700 } 701 702 npages = PAGE_ALIGN(desc->len) >> PAGE_SHIFT; 703 704 /* Transition the buffer to firmware-owned. */ 705 if (rmp_mark_pages_firmware(*desc->paddr_ptr, npages, true)) { 706 pr_warn("Error moving pages to firmware-owned state for SEV legacy command.\n"); 707 return -EFAULT; 708 } 709 710 return 0; 711 } 712 713 static int snp_unmap_cmd_buf_desc(struct cmd_buf_desc *desc) 714 { 715 unsigned int npages; 716 717 if (!desc->len) 718 return 0; 719 720 npages = PAGE_ALIGN(desc->len) >> PAGE_SHIFT; 721 722 /* Transition the buffers back to hypervisor-owned. */ 723 if (snp_reclaim_pages(*desc->paddr_ptr, npages, true)) { 724 pr_warn("Failed to reclaim firmware-owned pages while issuing SEV legacy command.\n"); 725 return -EFAULT; 726 } 727 728 /* Copy data from bounce buffer and then free it. */ 729 if (!desc->guest_owned) { 730 void *bounce_buf = __va(__sme_clr(*desc->paddr_ptr)); 731 void *dst_buf = __va(__sme_clr(desc->paddr_orig)); 732 733 memcpy(dst_buf, bounce_buf, desc->len); 734 __free_pages(virt_to_page(bounce_buf), get_order(desc->len)); 735 736 /* Restore the original address in the command buffer. */ 737 *desc->paddr_ptr = desc->paddr_orig; 738 } 739 740 return 0; 741 } 742 743 static int snp_map_cmd_buf_desc_list(int cmd, void *cmd_buf, struct cmd_buf_desc *desc_list) 744 { 745 int i; 746 747 snp_populate_cmd_buf_desc_list(cmd, cmd_buf, desc_list); 748 749 for (i = 0; i < CMD_BUF_DESC_MAX; i++) { 750 struct cmd_buf_desc *desc = &desc_list[i]; 751 752 if (!desc->paddr_ptr) 753 break; 754 755 if (snp_map_cmd_buf_desc(desc)) 756 goto err_unmap; 757 } 758 759 return 0; 760 761 err_unmap: 762 for (i--; i >= 0; i--) 763 snp_unmap_cmd_buf_desc(&desc_list[i]); 764 765 return -EFAULT; 766 } 767 768 static int snp_unmap_cmd_buf_desc_list(struct cmd_buf_desc *desc_list) 769 { 770 int i, ret = 0; 771 772 for (i = 0; i < CMD_BUF_DESC_MAX; i++) { 773 struct cmd_buf_desc *desc = &desc_list[i]; 774 775 if (!desc->paddr_ptr) 776 break; 777 778 if (snp_unmap_cmd_buf_desc(&desc_list[i])) 779 ret = -EFAULT; 780 } 781 782 return ret; 783 } 784 785 static bool sev_cmd_buf_writable(int cmd) 786 { 787 switch (cmd) { 788 case SEV_CMD_PLATFORM_STATUS: 789 case SEV_CMD_GUEST_STATUS: 790 case SEV_CMD_LAUNCH_START: 791 case SEV_CMD_RECEIVE_START: 792 case SEV_CMD_LAUNCH_MEASURE: 793 case SEV_CMD_SEND_START: 794 case SEV_CMD_SEND_UPDATE_DATA: 795 case SEV_CMD_SEND_UPDATE_VMSA: 796 case SEV_CMD_PEK_CSR: 797 case SEV_CMD_PDH_CERT_EXPORT: 798 case SEV_CMD_GET_ID: 799 case SEV_CMD_ATTESTATION_REPORT: 800 return true; 801 default: 802 return false; 803 } 804 } 805 806 /* After SNP is INIT'ed, the behavior of legacy SEV commands is changed. */ 807 static bool snp_legacy_handling_needed(int cmd) 808 { 809 struct sev_device *sev = psp_master->sev_data; 810 811 return cmd < SEV_CMD_SNP_INIT && sev->snp_initialized; 812 } 813 814 static int snp_prep_cmd_buf(int cmd, void *cmd_buf, struct cmd_buf_desc *desc_list) 815 { 816 if (!snp_legacy_handling_needed(cmd)) 817 return 0; 818 819 if (snp_map_cmd_buf_desc_list(cmd, cmd_buf, desc_list)) 820 return -EFAULT; 821 822 /* 823 * Before command execution, the command buffer needs to be put into 824 * the firmware-owned state. 825 */ 826 if (sev_cmd_buf_writable(cmd)) { 827 if (rmp_mark_pages_firmware(__pa(cmd_buf), 1, true)) 828 return -EFAULT; 829 } 830 831 return 0; 832 } 833 834 static int snp_reclaim_cmd_buf(int cmd, void *cmd_buf) 835 { 836 if (!snp_legacy_handling_needed(cmd)) 837 return 0; 838 839 /* 840 * After command completion, the command buffer needs to be put back 841 * into the hypervisor-owned state. 842 */ 843 if (sev_cmd_buf_writable(cmd)) 844 if (snp_reclaim_pages(__pa(cmd_buf), 1, true)) 845 return -EFAULT; 846 847 return 0; 848 } 849 850 int __sev_do_cmd_locked(int cmd, void *data, int *psp_ret) 851 { 852 struct cmd_buf_desc desc_list[CMD_BUF_DESC_MAX] = {0}; 853 struct psp_device *psp = psp_master; 854 struct sev_device *sev; 855 unsigned int cmdbuff_hi, cmdbuff_lo; 856 unsigned int phys_lsb, phys_msb; 857 unsigned int reg; 858 void *cmd_buf; 859 int buf_len; 860 int ret = 0; 861 862 if (!psp || !psp->sev_data) 863 return -ENODEV; 864 865 if (psp_dead) 866 return -EBUSY; 867 868 sev = psp->sev_data; 869 870 buf_len = sev_cmd_buffer_len(cmd); 871 if (WARN_ON_ONCE(!data != !buf_len)) 872 return -EINVAL; 873 874 /* 875 * Copy the incoming data to driver's scratch buffer as __pa() will not 876 * work for some memory, e.g. vmalloc'd addresses, and @data may not be 877 * physically contiguous. 878 */ 879 if (data) { 880 /* 881 * Commands are generally issued one at a time and require the 882 * sev_cmd_mutex, but there could be recursive firmware requests 883 * due to SEV_CMD_SNP_PAGE_RECLAIM needing to be issued while 884 * preparing buffers for another command. This is the only known 885 * case of nesting in the current code, so exactly one 886 * additional command buffer is available for that purpose. 887 */ 888 if (!sev->cmd_buf_active) { 889 cmd_buf = sev->cmd_buf; 890 sev->cmd_buf_active = true; 891 } else if (!sev->cmd_buf_backup_active) { 892 cmd_buf = sev->cmd_buf_backup; 893 sev->cmd_buf_backup_active = true; 894 } else { 895 dev_err(sev->dev, 896 "SEV: too many firmware commands in progress, no command buffers available.\n"); 897 return -EBUSY; 898 } 899 900 memcpy(cmd_buf, data, buf_len); 901 902 /* 903 * The behavior of the SEV-legacy commands is altered when the 904 * SNP firmware is in the INIT state. 905 */ 906 ret = snp_prep_cmd_buf(cmd, cmd_buf, desc_list); 907 if (ret) { 908 dev_err(sev->dev, 909 "SEV: failed to prepare buffer for legacy command 0x%x. Error: %d\n", 910 cmd, ret); 911 return ret; 912 } 913 } else { 914 cmd_buf = sev->cmd_buf; 915 } 916 917 /* Get the physical address of the command buffer */ 918 phys_lsb = data ? lower_32_bits(__psp_pa(cmd_buf)) : 0; 919 phys_msb = data ? upper_32_bits(__psp_pa(cmd_buf)) : 0; 920 921 dev_dbg(sev->dev, "sev command id %#x buffer 0x%08x%08x timeout %us\n", 922 cmd, phys_msb, phys_lsb, psp_timeout); 923 924 print_hex_dump_debug("(in): ", DUMP_PREFIX_OFFSET, 16, 2, data, 925 buf_len, false); 926 927 iowrite32(phys_lsb, sev->io_regs + sev->vdata->cmdbuff_addr_lo_reg); 928 iowrite32(phys_msb, sev->io_regs + sev->vdata->cmdbuff_addr_hi_reg); 929 930 sev->int_rcvd = 0; 931 932 reg = FIELD_PREP(SEV_CMDRESP_CMD, cmd); 933 934 /* 935 * If invoked during panic handling, local interrupts are disabled so 936 * the PSP command completion interrupt can't be used. 937 * sev_wait_cmd_ioc() already checks for interrupts disabled and 938 * polls for PSP command completion. Ensure we do not request an 939 * interrupt from the PSP if irqs disabled. 940 */ 941 if (!irqs_disabled()) 942 reg |= SEV_CMDRESP_IOC; 943 944 iowrite32(reg, sev->io_regs + sev->vdata->cmdresp_reg); 945 946 /* wait for command completion */ 947 ret = sev_wait_cmd_ioc(sev, ®, psp_timeout); 948 if (ret) { 949 if (psp_ret) 950 *psp_ret = 0; 951 952 dev_err(sev->dev, "sev command %#x timed out, disabling PSP\n", cmd); 953 psp_dead = true; 954 955 return ret; 956 } 957 958 psp_timeout = psp_cmd_timeout; 959 960 if (psp_ret) 961 *psp_ret = FIELD_GET(PSP_CMDRESP_STS, reg); 962 963 if (FIELD_GET(PSP_CMDRESP_STS, reg)) { 964 dev_dbg(sev->dev, "sev command %#x failed (%#010lx)\n", 965 cmd, FIELD_GET(PSP_CMDRESP_STS, reg)); 966 967 /* 968 * PSP firmware may report additional error information in the 969 * command buffer registers on error. Print contents of command 970 * buffer registers if they changed. 971 */ 972 cmdbuff_hi = ioread32(sev->io_regs + sev->vdata->cmdbuff_addr_hi_reg); 973 cmdbuff_lo = ioread32(sev->io_regs + sev->vdata->cmdbuff_addr_lo_reg); 974 if (cmdbuff_hi != phys_msb || cmdbuff_lo != phys_lsb) { 975 dev_dbg(sev->dev, "Additional error information reported in cmdbuff:"); 976 dev_dbg(sev->dev, " cmdbuff hi: %#010x\n", cmdbuff_hi); 977 dev_dbg(sev->dev, " cmdbuff lo: %#010x\n", cmdbuff_lo); 978 } 979 ret = -EIO; 980 } else { 981 ret = sev_write_init_ex_file_if_required(cmd); 982 } 983 984 /* 985 * Copy potential output from the PSP back to data. Do this even on 986 * failure in case the caller wants to glean something from the error. 987 */ 988 if (data) { 989 int ret_reclaim; 990 /* 991 * Restore the page state after the command completes. 992 */ 993 ret_reclaim = snp_reclaim_cmd_buf(cmd, cmd_buf); 994 if (ret_reclaim) { 995 dev_err(sev->dev, 996 "SEV: failed to reclaim buffer for legacy command %#x. Error: %d\n", 997 cmd, ret_reclaim); 998 return ret_reclaim; 999 } 1000 1001 memcpy(data, cmd_buf, buf_len); 1002 1003 if (sev->cmd_buf_backup_active) 1004 sev->cmd_buf_backup_active = false; 1005 else 1006 sev->cmd_buf_active = false; 1007 1008 if (snp_unmap_cmd_buf_desc_list(desc_list)) 1009 return -EFAULT; 1010 } 1011 1012 print_hex_dump_debug("(out): ", DUMP_PREFIX_OFFSET, 16, 2, data, 1013 buf_len, false); 1014 1015 return ret; 1016 } 1017 1018 int sev_do_cmd(int cmd, void *data, int *psp_ret) 1019 { 1020 int rc; 1021 1022 mutex_lock(&sev_cmd_mutex); 1023 rc = __sev_do_cmd_locked(cmd, data, psp_ret); 1024 mutex_unlock(&sev_cmd_mutex); 1025 1026 return rc; 1027 } 1028 EXPORT_SYMBOL_GPL(sev_do_cmd); 1029 1030 static int __sev_init_locked(int *error) 1031 { 1032 struct sev_data_init data; 1033 1034 memset(&data, 0, sizeof(data)); 1035 if (sev_es_tmr) { 1036 /* 1037 * Do not include the encryption mask on the physical 1038 * address of the TMR (firmware should clear it anyway). 1039 */ 1040 data.tmr_address = __pa(sev_es_tmr); 1041 1042 data.flags |= SEV_INIT_FLAGS_SEV_ES; 1043 data.tmr_len = sev_es_tmr_size; 1044 } 1045 1046 return __sev_do_cmd_locked(SEV_CMD_INIT, &data, error); 1047 } 1048 1049 static int __sev_init_ex_locked(int *error) 1050 { 1051 struct sev_data_init_ex data; 1052 1053 memset(&data, 0, sizeof(data)); 1054 data.length = sizeof(data); 1055 data.nv_address = __psp_pa(sev_init_ex_buffer); 1056 data.nv_len = NV_LENGTH; 1057 1058 if (sev_es_tmr) { 1059 /* 1060 * Do not include the encryption mask on the physical 1061 * address of the TMR (firmware should clear it anyway). 1062 */ 1063 data.tmr_address = __pa(sev_es_tmr); 1064 1065 data.flags |= SEV_INIT_FLAGS_SEV_ES; 1066 data.tmr_len = sev_es_tmr_size; 1067 } 1068 1069 return __sev_do_cmd_locked(SEV_CMD_INIT_EX, &data, error); 1070 } 1071 1072 static inline int __sev_do_init_locked(int *psp_ret) 1073 { 1074 if (sev_init_ex_buffer) 1075 return __sev_init_ex_locked(psp_ret); 1076 else 1077 return __sev_init_locked(psp_ret); 1078 } 1079 1080 /* Hypervisor Fixed pages API interface */ 1081 static void snp_hv_fixed_pages_state_update(struct sev_device *sev, 1082 enum snp_hv_fixed_pages_state page_state) 1083 { 1084 struct snp_hv_fixed_pages_entry *entry; 1085 1086 /* List is protected by sev_cmd_mutex */ 1087 lockdep_assert_held(&sev_cmd_mutex); 1088 1089 if (list_empty(&snp_hv_fixed_pages)) 1090 return; 1091 1092 list_for_each_entry(entry, &snp_hv_fixed_pages, list) 1093 entry->page_state = page_state; 1094 } 1095 1096 /* 1097 * Allocate HV_FIXED pages in 2MB aligned sizes to ensure the whole 1098 * 2MB pages are marked as HV_FIXED. 1099 */ 1100 struct page *snp_alloc_hv_fixed_pages(unsigned int num_2mb_pages) 1101 { 1102 struct psp_device *psp_master = psp_get_master_device(); 1103 struct snp_hv_fixed_pages_entry *entry; 1104 unsigned int order; 1105 struct page *page; 1106 1107 if (!psp_master) 1108 return NULL; 1109 1110 order = get_order(PMD_SIZE * num_2mb_pages); 1111 1112 /* 1113 * SNP_INIT_EX is protected by sev_cmd_mutex, therefore this list 1114 * also needs to be protected using the same mutex. 1115 */ 1116 guard(mutex)(&sev_cmd_mutex); 1117 1118 /* 1119 * This API uses SNP_INIT_EX to transition allocated pages to HV_Fixed 1120 * page state, fail if SNP is already initialized. 1121 */ 1122 if (psp_master->sev_data && 1123 ((struct sev_device *)psp_master->sev_data)->snp_initialized) 1124 return NULL; 1125 1126 /* Re-use freed pages that match the request */ 1127 list_for_each_entry(entry, &snp_hv_fixed_pages, list) { 1128 /* Hypervisor fixed page allocator implements exact fit policy */ 1129 if (entry->order == order && entry->free) { 1130 entry->free = false; 1131 memset(page_address(entry->page), 0, 1132 (1 << entry->order) * PAGE_SIZE); 1133 return entry->page; 1134 } 1135 } 1136 1137 page = alloc_pages(GFP_KERNEL | __GFP_ZERO, order); 1138 if (!page) 1139 return NULL; 1140 1141 entry = kzalloc_obj(*entry); 1142 if (!entry) { 1143 __free_pages(page, order); 1144 return NULL; 1145 } 1146 1147 entry->page = page; 1148 entry->order = order; 1149 list_add_tail(&entry->list, &snp_hv_fixed_pages); 1150 1151 return page; 1152 } 1153 1154 void snp_free_hv_fixed_pages(struct page *page) 1155 { 1156 struct psp_device *psp_master = psp_get_master_device(); 1157 struct snp_hv_fixed_pages_entry *entry, *nentry; 1158 1159 if (!psp_master) 1160 return; 1161 1162 /* 1163 * SNP_INIT_EX is protected by sev_cmd_mutex, therefore this list 1164 * also needs to be protected using the same mutex. 1165 */ 1166 guard(mutex)(&sev_cmd_mutex); 1167 1168 list_for_each_entry_safe(entry, nentry, &snp_hv_fixed_pages, list) { 1169 if (entry->page != page) 1170 continue; 1171 1172 /* 1173 * HV_FIXED page state cannot be changed until reboot 1174 * and they cannot be used by an SNP guest, so they cannot 1175 * be returned back to the page allocator. 1176 * Mark the pages as free internally to allow possible re-use. 1177 */ 1178 if (entry->page_state == HV_FIXED) { 1179 entry->free = true; 1180 } else { 1181 __free_pages(page, entry->order); 1182 list_del(&entry->list); 1183 kfree(entry); 1184 } 1185 return; 1186 } 1187 } 1188 1189 static void snp_add_hv_fixed_pages(struct sev_device *sev, struct sev_data_range_list *range_list) 1190 { 1191 struct snp_hv_fixed_pages_entry *entry; 1192 struct sev_data_range *range; 1193 int num_elements; 1194 1195 lockdep_assert_held(&sev_cmd_mutex); 1196 1197 if (list_empty(&snp_hv_fixed_pages)) 1198 return; 1199 1200 num_elements = list_count_nodes(&snp_hv_fixed_pages) + 1201 range_list->num_elements; 1202 1203 /* 1204 * Ensure the list of HV_FIXED pages that will be passed to firmware 1205 * do not exceed the page-sized argument buffer. 1206 */ 1207 if (num_elements * sizeof(*range) + sizeof(*range_list) > PAGE_SIZE) { 1208 dev_warn(sev->dev, "Additional HV_Fixed pages cannot be accommodated, omitting\n"); 1209 return; 1210 } 1211 1212 range = &range_list->ranges[range_list->num_elements]; 1213 list_for_each_entry(entry, &snp_hv_fixed_pages, list) { 1214 range->base = page_to_pfn(entry->page) << PAGE_SHIFT; 1215 range->page_count = 1 << entry->order; 1216 range++; 1217 } 1218 range_list->num_elements = num_elements; 1219 } 1220 1221 static void snp_leak_hv_fixed_pages(void) 1222 { 1223 struct snp_hv_fixed_pages_entry *entry, *nentry; 1224 1225 /* List is protected by sev_cmd_mutex */ 1226 lockdep_assert_held(&sev_cmd_mutex); 1227 1228 if (list_empty(&snp_hv_fixed_pages)) 1229 return; 1230 1231 list_for_each_entry_safe(entry, nentry, &snp_hv_fixed_pages, list) { 1232 if (entry->free && entry->page_state != HV_FIXED) 1233 __free_pages(entry->page, entry->order); 1234 else 1235 __snp_leak_pages(page_to_pfn(entry->page), 1236 1 << entry->order, false); 1237 1238 list_del(&entry->list); 1239 kfree(entry); 1240 } 1241 } 1242 1243 bool sev_is_snp_ciphertext_hiding_supported(void) 1244 { 1245 struct psp_device *psp = psp_master; 1246 struct sev_device *sev; 1247 1248 if (!psp || !psp->sev_data) 1249 return false; 1250 1251 sev = psp->sev_data; 1252 1253 /* 1254 * Feature information indicates if CipherTextHiding feature is 1255 * supported by the SEV firmware and additionally platform status 1256 * indicates if CipherTextHiding feature is enabled in the 1257 * Platform BIOS. 1258 */ 1259 return ((sev->snp_feat_info_0.ecx & SNP_CIPHER_TEXT_HIDING_SUPPORTED) && 1260 sev->snp_plat_status.ciphertext_hiding_cap); 1261 } 1262 EXPORT_SYMBOL_GPL(sev_is_snp_ciphertext_hiding_supported); 1263 1264 static int snp_get_platform_data(struct sev_device *sev, int *error) 1265 { 1266 struct sev_data_snp_feature_info snp_feat_info; 1267 struct snp_feature_info *feat_info; 1268 struct sev_data_snp_addr buf; 1269 struct page *page; 1270 int rc; 1271 1272 /* 1273 * This function is expected to be called before SNP is 1274 * initialized. 1275 */ 1276 if (sev->snp_initialized) 1277 return -EINVAL; 1278 1279 buf.address = __psp_pa(&sev->snp_plat_status); 1280 rc = sev_do_cmd(SEV_CMD_SNP_PLATFORM_STATUS, &buf, error); 1281 if (rc) { 1282 dev_err(sev->dev, "SNP PLATFORM_STATUS command failed, ret = %d, error = %#x\n", 1283 rc, *error); 1284 return rc; 1285 } 1286 1287 sev->api_major = sev->snp_plat_status.api_major; 1288 sev->api_minor = sev->snp_plat_status.api_minor; 1289 sev->build = sev->snp_plat_status.build_id; 1290 1291 /* 1292 * Do feature discovery of the currently loaded firmware, 1293 * and cache feature information from CPUID 0x8000_0024, 1294 * sub-function 0. 1295 */ 1296 if (!sev->snp_plat_status.feature_info) 1297 return 0; 1298 1299 /* 1300 * Use dynamically allocated structure for the SNP_FEATURE_INFO 1301 * command to ensure structure is 8-byte aligned, and does not 1302 * cross a page boundary. 1303 */ 1304 page = alloc_page(GFP_KERNEL); 1305 if (!page) 1306 return -ENOMEM; 1307 1308 feat_info = page_address(page); 1309 snp_feat_info.length = sizeof(snp_feat_info); 1310 snp_feat_info.ecx_in = 0; 1311 snp_feat_info.feature_info_paddr = __psp_pa(feat_info); 1312 1313 rc = sev_do_cmd(SEV_CMD_SNP_FEATURE_INFO, &snp_feat_info, error); 1314 if (!rc) 1315 sev->snp_feat_info_0 = *feat_info; 1316 else 1317 dev_err(sev->dev, "SNP FEATURE_INFO command failed, ret = %d, error = %#x\n", 1318 rc, *error); 1319 1320 __free_page(page); 1321 1322 return rc; 1323 } 1324 1325 static int snp_filter_reserved_mem_regions(struct resource *rs, void *arg) 1326 { 1327 struct sev_data_range_list *range_list = arg; 1328 struct sev_data_range *range = &range_list->ranges[range_list->num_elements]; 1329 size_t size; 1330 1331 /* 1332 * Ensure the list of HV_FIXED pages passed to the firmware including 1333 * the one about to be written to do not exceed the page-sized argument 1334 * buffer. 1335 */ 1336 if (((range_list->num_elements + 1) * sizeof(struct sev_data_range) + 1337 sizeof(struct sev_data_range_list)) > PAGE_SIZE) 1338 return -E2BIG; 1339 1340 switch (rs->desc) { 1341 case E820_TYPE_RESERVED: 1342 case E820_TYPE_PMEM: 1343 case E820_TYPE_ACPI: 1344 range->base = rs->start & PAGE_MASK; 1345 size = PAGE_ALIGN((rs->end + 1) - rs->start); 1346 range->page_count = size >> PAGE_SHIFT; 1347 range_list->num_elements++; 1348 break; 1349 default: 1350 break; 1351 } 1352 1353 return 0; 1354 } 1355 1356 #ifdef CONFIG_SYSFS 1357 static int snp_verify_mitigation(u16 command, u64 vector, 1358 struct sev_data_snp_verify_mitigation_dst *dst) 1359 { 1360 struct sev_data_snp_verify_mitigation_dst *mit_dst = NULL; 1361 struct sev_data_snp_verify_mitigation data = {0}; 1362 struct sev_device *sev = psp_master->sev_data; 1363 int ret, error = 0; 1364 1365 mit_dst = snp_alloc_firmware_page(GFP_KERNEL | __GFP_ZERO); 1366 if (!mit_dst) 1367 return -ENOMEM; 1368 1369 data.length = sizeof(data); 1370 data.subcommand = command; 1371 data.vector = vector; 1372 data.dst_paddr = __psp_pa(mit_dst); 1373 data.dst_paddr_en = true; 1374 1375 ret = sev_do_cmd(SEV_CMD_SNP_VERIFY_MITIGATION, &data, &error); 1376 if (!ret) 1377 memcpy(dst, mit_dst, sizeof(*mit_dst)); 1378 else 1379 dev_err(sev->dev, "SNP_VERIFY_MITIGATION command failed, ret = %d, error = %#x\n", 1380 ret, error); 1381 1382 snp_free_firmware_page(mit_dst); 1383 1384 return ret; 1385 } 1386 1387 static ssize_t supported_mitigations_show(struct kobject *kobj, 1388 struct kobj_attribute *attr, char *buf) 1389 { 1390 struct sev_data_snp_verify_mitigation_dst dst; 1391 int ret; 1392 1393 ret = snp_verify_mitigation(SNP_MIT_SUBCMD_REQ_STATUS, 0, &dst); 1394 if (ret) 1395 return ret; 1396 1397 return sysfs_emit(buf, "0x%llx\n", dst.mit_supported_vector); 1398 } 1399 1400 static struct kobj_attribute supported_attr = 1401 __ATTR_RO_MODE(supported_mitigations, 0400); 1402 1403 static ssize_t verified_mitigations_show(struct kobject *kobj, 1404 struct kobj_attribute *attr, char *buf) 1405 { 1406 struct sev_data_snp_verify_mitigation_dst dst; 1407 int ret; 1408 1409 ret = snp_verify_mitigation(SNP_MIT_SUBCMD_REQ_STATUS, 0, &dst); 1410 if (ret) 1411 return ret; 1412 1413 return sysfs_emit(buf, "0x%llx\n", dst.mit_verified_vector); 1414 } 1415 1416 static ssize_t verified_mitigations_store(struct kobject *kobj, 1417 struct kobj_attribute *attr, 1418 const char *buf, size_t count) 1419 { 1420 struct sev_data_snp_verify_mitigation_dst dst; 1421 struct sev_device *sev = psp_master->sev_data; 1422 u64 vector; 1423 int ret; 1424 1425 ret = kstrtoull(buf, 0, &vector); 1426 if (ret) 1427 return ret; 1428 1429 /* 1430 * The firmware verifies a single mitigation per call. Reject vectors 1431 * with more than one bit set early to avoid a guaranteed-to-fail call 1432 */ 1433 if (hweight64(vector) != 1) 1434 return -EINVAL; 1435 1436 ret = snp_verify_mitigation(SNP_MIT_SUBCMD_REQ_VERIFY, vector, &dst); 1437 if (ret) 1438 return ret; 1439 1440 if (dst.mit_failure_status) { 1441 dev_err(sev->dev, "Verify Mitigation - failure status: 0x%x\n", 1442 dst.mit_failure_status); 1443 return -EINVAL; 1444 } 1445 1446 return count; 1447 } 1448 1449 static struct kobj_attribute verified_attr = 1450 __ATTR_RW_MODE(verified_mitigations, 0600); 1451 1452 static struct attribute *mitigation_attrs[] = { 1453 &supported_attr.attr, 1454 &verified_attr.attr, 1455 NULL 1456 }; 1457 1458 static const struct attribute_group mit_attr_group = { 1459 .attrs = mitigation_attrs, 1460 }; 1461 1462 static void sev_snp_register_verify_mitigation(struct sev_device *sev) 1463 { 1464 int rc; 1465 1466 if (!(sev->snp_feat_info_0.ecx & SNP_VERIFY_MITIGATION_SUPPORTED) || 1467 sev->verify_mit) 1468 return; 1469 1470 if (!sev->sev_kobj) { 1471 sev->sev_kobj = kobject_create_and_add("sev", firmware_kobj); 1472 if (!sev->sev_kobj) 1473 return; 1474 } 1475 1476 sev->verify_mit = kobject_create_and_add("vulnerabilities", sev->sev_kobj); 1477 if (!sev->verify_mit) 1478 goto err_sev_kobj; 1479 1480 rc = sysfs_create_group(sev->verify_mit, &mit_attr_group); 1481 if (rc) 1482 goto err_verify_mit; 1483 1484 return; 1485 1486 err_verify_mit: 1487 kobject_put(sev->verify_mit); 1488 sev->verify_mit = NULL; 1489 err_sev_kobj: 1490 kobject_put(sev->sev_kobj); 1491 sev->sev_kobj = NULL; 1492 } 1493 1494 static void sev_snp_unregister_verify_mitigation(struct sev_device *sev) 1495 { 1496 if (sev->verify_mit) { 1497 sysfs_remove_group(sev->verify_mit, &mit_attr_group); 1498 kobject_put(sev->verify_mit); 1499 sev->verify_mit = NULL; 1500 } 1501 1502 if (sev->sev_kobj) { 1503 kobject_put(sev->sev_kobj); 1504 sev->sev_kobj = NULL; 1505 } 1506 } 1507 #else // CONFIG_SYSFS 1508 static void sev_snp_register_verify_mitigation(struct sev_device *sev) { } 1509 static void sev_snp_unregister_verify_mitigation(struct sev_device *sev) { } 1510 #endif // CONFIG_SYSFS 1511 1512 static int __sev_snp_init_locked(int *error, unsigned int max_snp_asid) 1513 { 1514 struct sev_data_range_list *snp_range_list __free(kfree) = NULL; 1515 struct psp_device *psp = psp_master; 1516 struct sev_data_snp_init_ex data = {}; 1517 struct sev_device *sev; 1518 void *arg = &data; 1519 int cmd, rc = 0; 1520 1521 if (!cc_platform_has(CC_ATTR_HOST_SEV_SNP)) 1522 return -ENODEV; 1523 1524 sev = psp->sev_data; 1525 1526 if (sev->snp_initialized) 1527 return 0; 1528 1529 if (!sev_version_greater_or_equal(SNP_MIN_API_MAJOR, SNP_MIN_API_MINOR)) { 1530 dev_dbg(sev->dev, "SEV-SNP support requires firmware version >= %d:%d\n", 1531 SNP_MIN_API_MAJOR, SNP_MIN_API_MINOR); 1532 return -EOPNOTSUPP; 1533 } 1534 1535 rc = snp_prepare(); 1536 if (rc) 1537 return rc; 1538 1539 /* 1540 * Starting in SNP firmware v1.52, the SNP_INIT_EX command takes a list 1541 * of system physical address ranges to convert into HV-fixed page 1542 * states during the RMP initialization. For instance, the memory that 1543 * UEFI reserves should be included in the that list. This allows system 1544 * components that occasionally write to memory (e.g. logging to UEFI 1545 * reserved regions) to not fail due to RMP initialization and SNP 1546 * enablement. 1547 * 1548 */ 1549 if (sev_version_greater_or_equal(SNP_MIN_API_MAJOR, 52)) { 1550 bool tio_supp = !!(sev->snp_feat_info_0.ebx & SNP_SEV_TIO_SUPPORTED); 1551 1552 /* 1553 * Firmware checks that the pages containing the ranges enumerated 1554 * in the RANGES structure are either in the default page state or in the 1555 * firmware page state. 1556 */ 1557 snp_range_list = kzalloc(PAGE_SIZE, GFP_KERNEL); 1558 if (!snp_range_list) { 1559 dev_err(sev->dev, 1560 "SEV: SNP_INIT_EX range list memory allocation failed\n"); 1561 return -ENOMEM; 1562 } 1563 1564 /* 1565 * Retrieve all reserved memory regions from the e820 memory map 1566 * to be setup as HV-fixed pages. 1567 */ 1568 rc = walk_iomem_res_desc(IORES_DESC_NONE, IORESOURCE_MEM, 0, ~0, 1569 snp_range_list, snp_filter_reserved_mem_regions); 1570 if (rc) { 1571 dev_err(sev->dev, 1572 "SEV: SNP_INIT_EX walk_iomem_res_desc failed rc = %d\n", rc); 1573 return rc; 1574 } 1575 1576 /* 1577 * Add HV_Fixed pages from other PSP sub-devices, such as SFS to the 1578 * HV_Fixed page list. 1579 */ 1580 snp_add_hv_fixed_pages(sev, snp_range_list); 1581 1582 if (max_snp_asid) { 1583 data.ciphertext_hiding_en = 1; 1584 data.max_snp_asid = max_snp_asid; 1585 } 1586 1587 data.init_rmp = 1; 1588 data.list_paddr_en = 1; 1589 data.list_paddr = __psp_pa(snp_range_list); 1590 1591 data.tio_en = tio_supp && sev_tio_enabled && amd_iommu_sev_tio_supported(); 1592 1593 /* 1594 * When psp_init_on_probe is disabled, the userspace calling 1595 * SEV ioctl can inadvertently shut down SNP and SEV-TIO causing 1596 * unexpected state loss. 1597 */ 1598 if (data.tio_en && !psp_init_on_probe) 1599 dev_warn(sev->dev, "SEV-TIO as incompatible with psp_init_on_probe=0\n"); 1600 1601 cmd = SEV_CMD_SNP_INIT_EX; 1602 } else { 1603 cmd = SEV_CMD_SNP_INIT; 1604 arg = NULL; 1605 } 1606 1607 /* 1608 * The following sequence must be issued before launching the first SNP 1609 * guest to ensure all dirty cache lines are flushed, including from 1610 * updates to the RMP table itself via the RMPUPDATE instruction: 1611 * 1612 * - WBINVD on all running CPUs 1613 * - SEV_CMD_SNP_INIT[_EX] firmware command 1614 * - WBINVD on all running CPUs 1615 * - SEV_CMD_SNP_DF_FLUSH firmware command 1616 */ 1617 wbinvd_on_all_cpus(); 1618 1619 rc = __sev_do_cmd_locked(cmd, arg, error); 1620 if (rc) { 1621 dev_err(sev->dev, "SEV-SNP: %s failed rc %d, error %#x\n", 1622 cmd == SEV_CMD_SNP_INIT_EX ? "SNP_INIT_EX" : "SNP_INIT", 1623 rc, *error); 1624 return rc; 1625 } 1626 1627 /* Prepare for first SNP guest launch after INIT. */ 1628 wbinvd_on_all_cpus(); 1629 rc = __sev_do_cmd_locked(SEV_CMD_SNP_DF_FLUSH, NULL, error); 1630 if (rc) { 1631 dev_err(sev->dev, "SEV-SNP: SNP_DF_FLUSH failed rc %d, error %#x\n", 1632 rc, *error); 1633 return rc; 1634 } 1635 1636 snp_hv_fixed_pages_state_update(sev, HV_FIXED); 1637 sev->snp_initialized = true; 1638 dev_dbg(sev->dev, "SEV-SNP firmware initialized, SEV-TIO is %s\n", 1639 data.tio_en ? "enabled" : "disabled"); 1640 1641 dev_info(sev->dev, "SEV-SNP API:%d.%d build:%d\n", sev->api_major, 1642 sev->api_minor, sev->build); 1643 1644 atomic_notifier_chain_register(&panic_notifier_list, 1645 &snp_panic_notifier); 1646 1647 if (data.tio_en) { 1648 struct page *page; 1649 1650 /* 1651 * This executes with the sev_cmd_mutex held so down the stack 1652 * snp_reclaim_pages(locked=false) might be needed (which is extremely 1653 * unlikely) but will cause a deadlock. 1654 * Instead of exporting __snp_alloc_firmware_pages(), allocate a page 1655 * for this one call here. 1656 */ 1657 page = __snp_alloc_firmware_pages(GFP_KERNEL_ACCOUNT | __GFP_ZERO, 1658 0, true); 1659 if (page) { 1660 void *tio_status = page_address(page); 1661 1662 sev_tsm_init_locked(sev, tio_status); 1663 1664 __snp_free_firmware_pages(page, 0, true); 1665 } 1666 } 1667 1668 sev_es_tmr_size = SNP_TMR_SIZE; 1669 1670 return 0; 1671 } 1672 1673 static void __sev_platform_init_handle_tmr(struct sev_device *sev) 1674 { 1675 if (sev_es_tmr) 1676 return; 1677 1678 /* Obtain the TMR memory area for SEV-ES use */ 1679 sev_es_tmr = sev_fw_alloc(sev_es_tmr_size); 1680 if (sev_es_tmr) { 1681 /* Must flush the cache before giving it to the firmware */ 1682 if (!sev->snp_initialized) 1683 clflush_cache_range(sev_es_tmr, sev_es_tmr_size); 1684 } else { 1685 dev_warn(sev->dev, "SEV: TMR allocation failed, SEV-ES support unavailable\n"); 1686 } 1687 } 1688 1689 /* 1690 * If an init_ex_path is provided allocate a buffer for the file and 1691 * read in the contents. Additionally, if SNP is initialized, convert 1692 * the buffer pages to firmware pages. 1693 */ 1694 static int __sev_platform_init_handle_init_ex_path(struct sev_device *sev) 1695 { 1696 struct page *page; 1697 int rc; 1698 1699 if (!init_ex_path) 1700 return 0; 1701 1702 if (sev_init_ex_buffer) 1703 return 0; 1704 1705 page = alloc_pages(GFP_KERNEL | __GFP_ZERO, get_order(NV_LENGTH)); 1706 if (!page) { 1707 dev_err(sev->dev, "SEV: INIT_EX NV memory allocation failed\n"); 1708 return -ENOMEM; 1709 } 1710 1711 sev_init_ex_buffer = page_address(page); 1712 1713 rc = sev_read_init_ex_file(); 1714 if (rc) 1715 goto err_free; 1716 1717 /* If SEV-SNP is initialized, transition to firmware page. */ 1718 if (sev->snp_initialized) { 1719 unsigned long npages; 1720 1721 npages = 1UL << get_order(NV_LENGTH); 1722 if (rmp_mark_pages_firmware(__pa(sev_init_ex_buffer), npages, true)) { 1723 dev_err(sev->dev, "SEV: INIT_EX NV memory page state change failed.\n"); 1724 rc = -ENOMEM; 1725 /* 1726 * Pages can be in an inconsistent state, don't release them back to the 1727 * system. 1728 */ 1729 goto err_reset; 1730 } 1731 } 1732 1733 return 0; 1734 1735 err_free: 1736 __free_pages(page, get_order(NV_LENGTH)); 1737 err_reset: 1738 sev_init_ex_buffer = NULL; 1739 return rc; 1740 } 1741 1742 static int __sev_platform_init_locked(int *error) 1743 { 1744 int rc, psp_ret, dfflush_error; 1745 struct sev_device *sev; 1746 1747 psp_ret = dfflush_error = SEV_RET_NO_FW_CALL; 1748 1749 if (!psp_master || !psp_master->sev_data) 1750 return -ENODEV; 1751 1752 sev = psp_master->sev_data; 1753 1754 if (sev->sev_plat_status.state == SEV_STATE_INIT) 1755 return 0; 1756 1757 __sev_platform_init_handle_tmr(sev); 1758 1759 rc = __sev_platform_init_handle_init_ex_path(sev); 1760 if (rc) 1761 return rc; 1762 1763 rc = __sev_do_init_locked(&psp_ret); 1764 if (rc && psp_ret == SEV_RET_SECURE_DATA_INVALID) { 1765 /* 1766 * Initialization command returned an integrity check failure 1767 * status code, meaning that firmware load and validation of SEV 1768 * related persistent data has failed. Retrying the 1769 * initialization function should succeed by replacing the state 1770 * with a reset state. 1771 */ 1772 dev_err(sev->dev, 1773 "SEV: retrying INIT command because of SECURE_DATA_INVALID error. Retrying once to reset PSP SEV state."); 1774 rc = __sev_do_init_locked(&psp_ret); 1775 } 1776 1777 if (error) 1778 *error = psp_ret; 1779 1780 if (rc) { 1781 dev_err(sev->dev, "SEV: %s failed %#x, rc %d\n", 1782 sev_init_ex_buffer ? "INIT_EX" : "INIT", psp_ret, rc); 1783 return rc; 1784 } 1785 1786 sev->sev_plat_status.state = SEV_STATE_INIT; 1787 1788 /* Prepare for first SEV guest launch after INIT */ 1789 wbinvd_on_all_cpus(); 1790 rc = __sev_do_cmd_locked(SEV_CMD_DF_FLUSH, NULL, &dfflush_error); 1791 if (rc) { 1792 dev_err(sev->dev, "SEV: DF_FLUSH failed %#x, rc %d\n", 1793 dfflush_error, rc); 1794 return rc; 1795 } 1796 1797 dev_dbg(sev->dev, "SEV firmware initialized\n"); 1798 1799 dev_info(sev->dev, "SEV API:%d.%d build:%d\n", sev->api_major, 1800 sev->api_minor, sev->build); 1801 1802 return 0; 1803 } 1804 1805 static int _sev_platform_init_locked(struct sev_platform_init_args *args) 1806 { 1807 struct sev_device *sev; 1808 int rc; 1809 1810 if (!psp_master || !psp_master->sev_data) 1811 return -ENODEV; 1812 1813 /* 1814 * Skip SNP/SEV initialization under a kdump kernel as SEV/SNP 1815 * may already be initialized in the previous kernel. Since no 1816 * SNP/SEV guests are run under a kdump kernel, there is no 1817 * need to initialize SNP or SEV during kdump boot. 1818 */ 1819 if (is_kdump_kernel()) 1820 return 0; 1821 1822 sev = psp_master->sev_data; 1823 1824 if (sev->sev_plat_status.state == SEV_STATE_INIT) 1825 return 0; 1826 1827 rc = __sev_snp_init_locked(&args->error, args->max_snp_asid); 1828 if (rc && rc != -ENODEV) 1829 return rc; 1830 1831 /* Defer legacy SEV/SEV-ES support if allowed by caller/module. */ 1832 if (args->probe && !psp_init_on_probe) 1833 return 0; 1834 1835 return __sev_platform_init_locked(&args->error); 1836 } 1837 1838 int sev_platform_init(struct sev_platform_init_args *args) 1839 { 1840 int rc; 1841 1842 mutex_lock(&sev_cmd_mutex); 1843 rc = _sev_platform_init_locked(args); 1844 mutex_unlock(&sev_cmd_mutex); 1845 1846 /* 1847 * Register the sysfs interface outside the sev_cmd_mutex. The 1848 * _show()/_store() handlers issue SEV commands that acquire the 1849 * sev_cmd_mutex, so creating (and on the shutdown path, removing) the 1850 * sysfs group must stay outside that lock. sysfs provides its own 1851 * synchronization between group creation/removal and concurrent 1852 * attribute access. 1853 */ 1854 if (!rc) 1855 sev_snp_register_verify_mitigation(psp_master->sev_data); 1856 1857 return rc; 1858 } 1859 EXPORT_SYMBOL_GPL(sev_platform_init); 1860 1861 static int __sev_platform_shutdown_locked(int *error) 1862 { 1863 struct psp_device *psp = psp_master; 1864 struct sev_device *sev; 1865 int ret; 1866 1867 if (!psp || !psp->sev_data) 1868 return 0; 1869 1870 sev = psp->sev_data; 1871 1872 if (sev->sev_plat_status.state == SEV_STATE_UNINIT) 1873 return 0; 1874 1875 ret = __sev_do_cmd_locked(SEV_CMD_SHUTDOWN, NULL, error); 1876 if (ret) { 1877 dev_err(sev->dev, "SEV: failed to SHUTDOWN error %#x, rc %d\n", 1878 *error, ret); 1879 return ret; 1880 } 1881 1882 sev->sev_plat_status.state = SEV_STATE_UNINIT; 1883 dev_dbg(sev->dev, "SEV firmware shutdown\n"); 1884 1885 return ret; 1886 } 1887 1888 static int sev_get_platform_state(int *state, int *error) 1889 { 1890 struct sev_user_data_status data; 1891 int rc; 1892 1893 rc = __sev_do_cmd_locked(SEV_CMD_PLATFORM_STATUS, &data, error); 1894 if (rc) 1895 return rc; 1896 1897 *state = data.state; 1898 return rc; 1899 } 1900 1901 static int sev_move_to_init_state(struct sev_issue_cmd *argp, bool *shutdown_required) 1902 { 1903 int rc; 1904 1905 rc = __sev_platform_init_locked(&argp->error); 1906 if (rc) 1907 return rc; 1908 1909 *shutdown_required = true; 1910 1911 return 0; 1912 } 1913 1914 static int sev_ioctl_do_reset(struct sev_issue_cmd *argp, bool writable) 1915 { 1916 int state, rc; 1917 1918 if (!writable) 1919 return -EPERM; 1920 1921 /* 1922 * The SEV spec requires that FACTORY_RESET must be issued in 1923 * UNINIT state. Before we go further lets check if any guest is 1924 * active. 1925 * 1926 * If FW is in WORKING state then deny the request otherwise issue 1927 * SHUTDOWN command do INIT -> UNINIT before issuing the FACTORY_RESET. 1928 * 1929 */ 1930 rc = sev_get_platform_state(&state, &argp->error); 1931 if (rc) 1932 return rc; 1933 1934 if (state == SEV_STATE_WORKING) 1935 return -EBUSY; 1936 1937 if (state == SEV_STATE_INIT) { 1938 rc = __sev_platform_shutdown_locked(&argp->error); 1939 if (rc) 1940 return rc; 1941 } 1942 1943 return __sev_do_cmd_locked(SEV_CMD_FACTORY_RESET, NULL, &argp->error); 1944 } 1945 1946 static int sev_ioctl_do_platform_status(struct sev_issue_cmd *argp) 1947 { 1948 struct sev_user_data_status data; 1949 int ret; 1950 1951 memset(&data, 0, sizeof(data)); 1952 1953 ret = __sev_do_cmd_locked(SEV_CMD_PLATFORM_STATUS, &data, &argp->error); 1954 if (ret) 1955 return ret; 1956 1957 if (copy_to_user((void __user *)argp->data, &data, sizeof(data))) 1958 ret = -EFAULT; 1959 1960 return ret; 1961 } 1962 1963 static int sev_ioctl_do_pek_pdh_gen(int cmd, struct sev_issue_cmd *argp, bool writable) 1964 { 1965 struct sev_device *sev = psp_master->sev_data; 1966 bool shutdown_required = false; 1967 int rc; 1968 1969 if (!writable) 1970 return -EPERM; 1971 1972 if (sev->sev_plat_status.state == SEV_STATE_UNINIT) { 1973 rc = sev_move_to_init_state(argp, &shutdown_required); 1974 if (rc) 1975 return rc; 1976 } 1977 1978 rc = __sev_do_cmd_locked(cmd, NULL, &argp->error); 1979 1980 if (shutdown_required) 1981 __sev_firmware_shutdown(sev, false); 1982 1983 return rc; 1984 } 1985 1986 static int sev_ioctl_do_pek_csr(struct sev_issue_cmd *argp, bool writable) 1987 { 1988 struct sev_device *sev = psp_master->sev_data; 1989 struct sev_user_data_pek_csr input; 1990 bool shutdown_required = false; 1991 struct sev_data_pek_csr data; 1992 void __user *input_address; 1993 void *blob = NULL; 1994 int ret; 1995 1996 if (!writable) 1997 return -EPERM; 1998 1999 if (copy_from_user(&input, (void __user *)argp->data, sizeof(input))) 2000 return -EFAULT; 2001 2002 memset(&data, 0, sizeof(data)); 2003 2004 /* userspace wants to query CSR length */ 2005 if (!input.address || !input.length) 2006 goto cmd; 2007 2008 /* allocate a physically contiguous buffer to store the CSR blob */ 2009 input_address = (void __user *)input.address; 2010 if (input.length > SEV_FW_BLOB_MAX_SIZE) 2011 return -EFAULT; 2012 2013 blob = kzalloc(input.length, GFP_KERNEL); 2014 if (!blob) 2015 return -ENOMEM; 2016 2017 data.address = __psp_pa(blob); 2018 data.len = input.length; 2019 2020 cmd: 2021 if (sev->sev_plat_status.state == SEV_STATE_UNINIT) { 2022 ret = sev_move_to_init_state(argp, &shutdown_required); 2023 if (ret) 2024 goto e_free_blob; 2025 } 2026 2027 ret = __sev_do_cmd_locked(SEV_CMD_PEK_CSR, &data, &argp->error); 2028 2029 /* 2030 * Firmware will returns the length of the CSR blob (either the minimum 2031 * required length or the actual length written), return it to the user. 2032 */ 2033 input.length = data.len; 2034 2035 if (copy_to_user((void __user *)argp->data, &input, sizeof(input))) { 2036 ret = -EFAULT; 2037 goto e_free_blob; 2038 } 2039 2040 if (ret || WARN_ON_ONCE(argp->error)) 2041 goto e_free_blob; 2042 2043 if (blob) { 2044 if (copy_to_user(input_address, blob, input.length)) 2045 ret = -EFAULT; 2046 } 2047 2048 e_free_blob: 2049 if (shutdown_required) 2050 __sev_firmware_shutdown(sev, false); 2051 2052 kfree(blob); 2053 return ret; 2054 } 2055 2056 void *psp_copy_user_blob(u64 uaddr, u32 len) 2057 { 2058 if (!uaddr || !len) 2059 return ERR_PTR(-EINVAL); 2060 2061 /* verify that blob length does not exceed our limit */ 2062 if (len > SEV_FW_BLOB_MAX_SIZE) 2063 return ERR_PTR(-EINVAL); 2064 2065 return memdup_user((void __user *)uaddr, len); 2066 } 2067 EXPORT_SYMBOL_GPL(psp_copy_user_blob); 2068 2069 static int sev_get_api_version(void) 2070 { 2071 struct sev_device *sev = psp_master->sev_data; 2072 struct sev_user_data_status status; 2073 int error = 0, ret; 2074 2075 /* 2076 * Cache SNP platform status and SNP feature information 2077 * if SNP is available. 2078 */ 2079 if (cc_platform_has(CC_ATTR_HOST_SEV_SNP)) { 2080 ret = snp_get_platform_data(sev, &error); 2081 if (ret) 2082 return 1; 2083 } 2084 2085 ret = sev_platform_status(&status, &error); 2086 if (ret) { 2087 dev_err(sev->dev, 2088 "SEV: failed to get status. Error: %#x\n", error); 2089 return 1; 2090 } 2091 2092 /* Cache SEV platform status */ 2093 sev->sev_plat_status = status; 2094 2095 sev->api_major = status.api_major; 2096 sev->api_minor = status.api_minor; 2097 sev->build = status.build; 2098 2099 return 0; 2100 } 2101 2102 static int sev_get_firmware(struct device *dev, 2103 const struct firmware **firmware) 2104 { 2105 char fw_name_specific[SEV_FW_NAME_SIZE]; 2106 char fw_name_subset[SEV_FW_NAME_SIZE]; 2107 2108 snprintf(fw_name_specific, sizeof(fw_name_specific), 2109 "amd/amd_sev_fam%.2xh_model%.2xh.sbin", 2110 boot_cpu_data.x86, boot_cpu_data.x86_model); 2111 2112 snprintf(fw_name_subset, sizeof(fw_name_subset), 2113 "amd/amd_sev_fam%.2xh_model%.1xxh.sbin", 2114 boot_cpu_data.x86, (boot_cpu_data.x86_model & 0xf0) >> 4); 2115 2116 /* Check for SEV FW for a particular model. 2117 * Ex. amd_sev_fam17h_model00h.sbin for Family 17h Model 00h 2118 * 2119 * or 2120 * 2121 * Check for SEV FW common to a subset of models. 2122 * Ex. amd_sev_fam17h_model0xh.sbin for 2123 * Family 17h Model 00h -- Family 17h Model 0Fh 2124 * 2125 * or 2126 * 2127 * Fall-back to using generic name: sev.fw 2128 */ 2129 if ((firmware_request_nowarn(firmware, fw_name_specific, dev) >= 0) || 2130 (firmware_request_nowarn(firmware, fw_name_subset, dev) >= 0) || 2131 (firmware_request_nowarn(firmware, SEV_FW_FILE, dev) >= 0)) 2132 return 0; 2133 2134 return -ENOENT; 2135 } 2136 2137 /* Don't fail if SEV FW couldn't be updated. Continue with existing SEV FW */ 2138 static int sev_update_firmware(struct device *dev) 2139 { 2140 struct sev_data_download_firmware data; 2141 const struct firmware *firmware; 2142 int ret, error, order; 2143 struct page *p; 2144 void *fw_blob; 2145 2146 if (!sev_version_greater_or_equal(0, 15)) { 2147 dev_dbg(dev, "DOWNLOAD_FIRMWARE not supported\n"); 2148 return -1; 2149 } 2150 2151 if (sev_get_firmware(dev, &firmware) == -ENOENT) { 2152 dev_dbg(dev, "No SEV firmware file present\n"); 2153 return -1; 2154 } 2155 2156 order = get_order(firmware->size); 2157 p = alloc_pages(GFP_KERNEL, order); 2158 if (!p) { 2159 ret = -1; 2160 goto fw_err; 2161 } 2162 2163 /* 2164 * Copy firmware data to a kernel allocated contiguous 2165 * memory region. 2166 */ 2167 fw_blob = page_address(p); 2168 memcpy(fw_blob, firmware->data, firmware->size); 2169 2170 data.address = __psp_pa(fw_blob); 2171 data.len = firmware->size; 2172 2173 ret = sev_do_cmd(SEV_CMD_DOWNLOAD_FIRMWARE, &data, &error); 2174 2175 /* 2176 * A quirk for fixing the committed TCB version, when upgrading from 2177 * earlier firmware version than 1.50. 2178 */ 2179 if (!ret && !sev_version_greater_or_equal(1, 50)) 2180 ret = sev_do_cmd(SEV_CMD_DOWNLOAD_FIRMWARE, &data, &error); 2181 2182 if (ret) 2183 dev_dbg(dev, "Failed to update SEV firmware: %#x\n", error); 2184 2185 __free_pages(p, order); 2186 2187 fw_err: 2188 release_firmware(firmware); 2189 2190 return ret; 2191 } 2192 2193 static int __sev_snp_shutdown_locked(int *error, bool panic) 2194 { 2195 struct psp_device *psp = psp_master; 2196 struct sev_device *sev; 2197 struct sev_data_snp_shutdown_ex data; 2198 int ret; 2199 2200 if (!psp || !psp->sev_data) 2201 return 0; 2202 2203 sev = psp->sev_data; 2204 2205 if (!sev->snp_initialized) 2206 return 0; 2207 2208 memset(&data, 0, sizeof(data)); 2209 data.len = sizeof(data); 2210 data.iommu_snp_shutdown = 1; 2211 if (sev->snp_feat_info_0.ecx & SNP_X86_SHUTDOWN_SUPPORTED) 2212 data.x86_snp_shutdown = 1; 2213 2214 /* 2215 * If invoked during panic handling, local interrupts are disabled 2216 * and all CPUs are stopped, so wbinvd_on_all_cpus() can't be called. 2217 * In that case, a wbinvd() is done on remote CPUs via the NMI 2218 * callback, so only a local wbinvd() is needed here. 2219 */ 2220 if (!panic) 2221 wbinvd_on_all_cpus(); 2222 else 2223 wbinvd(); 2224 2225 ret = __sev_do_cmd_locked(SEV_CMD_SNP_SHUTDOWN_EX, &data, error); 2226 /* SHUTDOWN may require DF_FLUSH */ 2227 if (*error == SEV_RET_DFFLUSH_REQUIRED) { 2228 int dfflush_error = SEV_RET_NO_FW_CALL; 2229 2230 ret = __sev_do_cmd_locked(SEV_CMD_SNP_DF_FLUSH, NULL, &dfflush_error); 2231 if (ret) { 2232 dev_err(sev->dev, "SEV-SNP DF_FLUSH failed, ret = %d, error = %#x\n", 2233 ret, dfflush_error); 2234 return ret; 2235 } 2236 /* reissue the shutdown command */ 2237 ret = __sev_do_cmd_locked(SEV_CMD_SNP_SHUTDOWN_EX, &data, 2238 error); 2239 } 2240 if (ret) { 2241 dev_err(sev->dev, "SEV-SNP firmware shutdown failed, rc %d, error %#x\n", 2242 ret, *error); 2243 return ret; 2244 } 2245 2246 if (data.x86_snp_shutdown) { 2247 if (!panic) 2248 snp_shutdown(); 2249 snp_hv_fixed_pages_state_update(sev, ALLOCATED); 2250 } else { 2251 /* 2252 * SNP_SHUTDOWN_EX with IOMMU_SNP_SHUTDOWN set to 1 disables SNP 2253 * enforcement by the IOMMU and also transitions all pages 2254 * associated with the IOMMU to the Reclaim state. 2255 * Firmware was transitioning the IOMMU pages to Hypervisor state 2256 * before version 1.53. But, accounting for the number of assigned 2257 * 4kB pages in a 2M page was done incorrectly by not transitioning 2258 * to the Reclaim state. This resulted in RMP #PF when later accessing 2259 * the 2M page containing those pages during kexec boot. Hence, the 2260 * firmware now transitions these pages to Reclaim state and hypervisor 2261 * needs to transition these pages to shared state. SNP Firmware 2262 * version 1.53 and above are needed for kexec boot. 2263 */ 2264 ret = amd_iommu_snp_disable(); 2265 if (ret) { 2266 dev_err(sev->dev, "SNP IOMMU shutdown failed\n"); 2267 return ret; 2268 } 2269 } 2270 2271 snp_leak_hv_fixed_pages(); 2272 sev->snp_initialized = false; 2273 dev_dbg(sev->dev, "SEV-SNP firmware shutdown\n"); 2274 2275 /* 2276 * __sev_snp_shutdown_locked() deadlocks when it tries to unregister 2277 * itself during panic as the panic notifier is called with RCU read 2278 * lock held and notifier unregistration does RCU synchronization. 2279 */ 2280 if (!panic) 2281 atomic_notifier_chain_unregister(&panic_notifier_list, 2282 &snp_panic_notifier); 2283 2284 /* Reset TMR size back to default */ 2285 sev_es_tmr_size = SEV_TMR_SIZE; 2286 2287 return ret; 2288 } 2289 2290 static int sev_ioctl_do_pek_import(struct sev_issue_cmd *argp, bool writable) 2291 { 2292 struct sev_device *sev = psp_master->sev_data; 2293 struct sev_user_data_pek_cert_import input; 2294 struct sev_data_pek_cert_import data; 2295 bool shutdown_required = false; 2296 void *pek_blob, *oca_blob; 2297 int ret; 2298 2299 if (!writable) 2300 return -EPERM; 2301 2302 if (copy_from_user(&input, (void __user *)argp->data, sizeof(input))) 2303 return -EFAULT; 2304 2305 /* copy PEK certificate blobs from userspace */ 2306 pek_blob = psp_copy_user_blob(input.pek_cert_address, input.pek_cert_len); 2307 if (IS_ERR(pek_blob)) 2308 return PTR_ERR(pek_blob); 2309 2310 data.reserved = 0; 2311 data.pek_cert_address = __psp_pa(pek_blob); 2312 data.pek_cert_len = input.pek_cert_len; 2313 2314 /* copy PEK certificate blobs from userspace */ 2315 oca_blob = psp_copy_user_blob(input.oca_cert_address, input.oca_cert_len); 2316 if (IS_ERR(oca_blob)) { 2317 ret = PTR_ERR(oca_blob); 2318 goto e_free_pek; 2319 } 2320 2321 data.oca_cert_address = __psp_pa(oca_blob); 2322 data.oca_cert_len = input.oca_cert_len; 2323 2324 /* If platform is not in INIT state then transition it to INIT */ 2325 if (sev->sev_plat_status.state != SEV_STATE_INIT) { 2326 ret = sev_move_to_init_state(argp, &shutdown_required); 2327 if (ret) 2328 goto e_free_oca; 2329 } 2330 2331 ret = __sev_do_cmd_locked(SEV_CMD_PEK_CERT_IMPORT, &data, &argp->error); 2332 2333 e_free_oca: 2334 if (shutdown_required) 2335 __sev_firmware_shutdown(sev, false); 2336 2337 kfree(oca_blob); 2338 e_free_pek: 2339 kfree(pek_blob); 2340 return ret; 2341 } 2342 2343 static int sev_ioctl_do_get_id2(struct sev_issue_cmd *argp) 2344 { 2345 struct sev_user_data_get_id2 input; 2346 struct sev_data_get_id data; 2347 void __user *input_address; 2348 void *id_blob = NULL; 2349 int ret; 2350 2351 /* SEV GET_ID is available from SEV API v0.16 and up */ 2352 if (!sev_version_greater_or_equal(0, 16)) 2353 return -ENOTSUPP; 2354 2355 if (copy_from_user(&input, (void __user *)argp->data, sizeof(input))) 2356 return -EFAULT; 2357 2358 input_address = (void __user *)input.address; 2359 2360 if (input.address && input.length) { 2361 /* 2362 * The length of the ID shouldn't be assumed by software since 2363 * it may change in the future. The allocation size is limited 2364 * to 1 << (PAGE_SHIFT + MAX_PAGE_ORDER) by the page allocator. 2365 * If the allocation fails, simply return ENOMEM rather than 2366 * warning in the kernel log. 2367 */ 2368 id_blob = kzalloc(input.length, GFP_KERNEL | __GFP_NOWARN); 2369 if (!id_blob) 2370 return -ENOMEM; 2371 2372 data.address = __psp_pa(id_blob); 2373 data.len = input.length; 2374 } else { 2375 data.address = 0; 2376 data.len = 0; 2377 } 2378 2379 ret = __sev_do_cmd_locked(SEV_CMD_GET_ID, &data, &argp->error); 2380 2381 /* 2382 * Firmware will return the length of the ID value (either the minimum 2383 * required length or the actual length written), return it to the user. 2384 */ 2385 input.length = data.len; 2386 2387 if (copy_to_user((void __user *)argp->data, &input, sizeof(input))) { 2388 ret = -EFAULT; 2389 goto e_free; 2390 } 2391 2392 if (ret || WARN_ON_ONCE(argp->error)) 2393 goto e_free; 2394 2395 if (id_blob) { 2396 if (copy_to_user(input_address, id_blob, data.len)) { 2397 ret = -EFAULT; 2398 goto e_free; 2399 } 2400 } 2401 2402 e_free: 2403 kfree(id_blob); 2404 2405 return ret; 2406 } 2407 2408 static int sev_ioctl_do_get_id(struct sev_issue_cmd *argp) 2409 { 2410 struct sev_data_get_id *data; 2411 u64 data_size, user_size; 2412 void *id_blob, *mem; 2413 int ret; 2414 2415 /* SEV GET_ID available from SEV API v0.16 and up */ 2416 if (!sev_version_greater_or_equal(0, 16)) 2417 return -ENOTSUPP; 2418 2419 /* SEV FW expects the buffer it fills with the ID to be 2420 * 8-byte aligned. Memory allocated should be enough to 2421 * hold data structure + alignment padding + memory 2422 * where SEV FW writes the ID. 2423 */ 2424 data_size = ALIGN(sizeof(struct sev_data_get_id), 8); 2425 user_size = sizeof(struct sev_user_data_get_id); 2426 2427 mem = kzalloc(data_size + user_size, GFP_KERNEL); 2428 if (!mem) 2429 return -ENOMEM; 2430 2431 data = mem; 2432 id_blob = mem + data_size; 2433 2434 data->address = __psp_pa(id_blob); 2435 data->len = user_size; 2436 2437 ret = __sev_do_cmd_locked(SEV_CMD_GET_ID, data, &argp->error); 2438 if (!ret) { 2439 if (copy_to_user((void __user *)argp->data, id_blob, data->len)) 2440 ret = -EFAULT; 2441 } 2442 2443 kfree(mem); 2444 2445 return ret; 2446 } 2447 2448 static int sev_ioctl_do_pdh_export(struct sev_issue_cmd *argp, bool writable) 2449 { 2450 struct sev_device *sev = psp_master->sev_data; 2451 struct sev_user_data_pdh_cert_export input; 2452 void *pdh_blob = NULL, *cert_blob = NULL; 2453 struct sev_data_pdh_cert_export data; 2454 void __user *input_cert_chain_address; 2455 void __user *input_pdh_cert_address; 2456 bool shutdown_required = false; 2457 int ret; 2458 2459 if (copy_from_user(&input, (void __user *)argp->data, sizeof(input))) 2460 return -EFAULT; 2461 2462 memset(&data, 0, sizeof(data)); 2463 2464 input_pdh_cert_address = (void __user *)input.pdh_cert_address; 2465 input_cert_chain_address = (void __user *)input.cert_chain_address; 2466 2467 /* Userspace wants to query the certificate length. */ 2468 if (!input.pdh_cert_address || 2469 !input.pdh_cert_len || 2470 !input.cert_chain_address || 2471 !input.cert_chain_len) 2472 goto cmd; 2473 2474 /* Allocate a physically contiguous buffer to store the PDH blob. */ 2475 if (input.pdh_cert_len > SEV_FW_BLOB_MAX_SIZE) 2476 return -EFAULT; 2477 2478 /* Allocate a physically contiguous buffer to store the cert chain blob. */ 2479 if (input.cert_chain_len > SEV_FW_BLOB_MAX_SIZE) 2480 return -EFAULT; 2481 2482 pdh_blob = kzalloc(input.pdh_cert_len, GFP_KERNEL); 2483 if (!pdh_blob) 2484 return -ENOMEM; 2485 2486 data.pdh_cert_address = __psp_pa(pdh_blob); 2487 data.pdh_cert_len = input.pdh_cert_len; 2488 2489 cert_blob = kzalloc(input.cert_chain_len, GFP_KERNEL); 2490 if (!cert_blob) { 2491 ret = -ENOMEM; 2492 goto e_free_pdh; 2493 } 2494 2495 data.cert_chain_address = __psp_pa(cert_blob); 2496 data.cert_chain_len = input.cert_chain_len; 2497 2498 cmd: 2499 /* If platform is not in INIT state then transition it to INIT. */ 2500 if (sev->sev_plat_status.state != SEV_STATE_INIT) { 2501 if (!writable) { 2502 ret = -EPERM; 2503 goto e_free_cert; 2504 } 2505 ret = sev_move_to_init_state(argp, &shutdown_required); 2506 if (ret) 2507 goto e_free_cert; 2508 } 2509 2510 ret = __sev_do_cmd_locked(SEV_CMD_PDH_CERT_EXPORT, &data, &argp->error); 2511 2512 /* 2513 * Firmware will return the length of the blobs (either the minimum 2514 * required length or the actual length written), return 'em to the user. 2515 */ 2516 input.cert_chain_len = data.cert_chain_len; 2517 input.pdh_cert_len = data.pdh_cert_len; 2518 2519 if (copy_to_user((void __user *)argp->data, &input, sizeof(input))) { 2520 ret = -EFAULT; 2521 goto e_free_cert; 2522 } 2523 2524 if (ret || WARN_ON_ONCE(argp->error)) 2525 goto e_free_cert; 2526 2527 if (pdh_blob) { 2528 if (copy_to_user(input_pdh_cert_address, 2529 pdh_blob, input.pdh_cert_len)) { 2530 ret = -EFAULT; 2531 goto e_free_cert; 2532 } 2533 } 2534 2535 if (cert_blob) { 2536 if (copy_to_user(input_cert_chain_address, 2537 cert_blob, input.cert_chain_len)) 2538 ret = -EFAULT; 2539 } 2540 2541 e_free_cert: 2542 if (shutdown_required) 2543 __sev_firmware_shutdown(sev, false); 2544 2545 kfree(cert_blob); 2546 e_free_pdh: 2547 kfree(pdh_blob); 2548 return ret; 2549 } 2550 2551 static int __sev_do_snp_platform_status(struct sev_user_data_snp_status *status, 2552 int *error) 2553 { 2554 struct sev_device *sev = psp_master->sev_data; 2555 struct sev_data_snp_addr buf; 2556 struct page *status_page; 2557 void *data; 2558 int ret; 2559 2560 status_page = alloc_page(GFP_KERNEL_ACCOUNT); 2561 if (!status_page) 2562 return -ENOMEM; 2563 2564 data = page_address(status_page); 2565 2566 /* 2567 * SNP_PLATFORM_STATUS can be executed in any SNP state. But if executed 2568 * when SNP has been initialized, the status page must be firmware-owned. 2569 */ 2570 if (sev->snp_initialized) { 2571 /* 2572 * Firmware expects the status page to be in Firmware state, 2573 * otherwise it will report an error INVALID_PAGE_STATE. 2574 */ 2575 if (rmp_mark_pages_firmware(__pa(data), 1, true)) { 2576 ret = -EFAULT; 2577 goto cleanup; 2578 } 2579 } 2580 2581 buf.address = __psp_pa(data); 2582 ret = __sev_do_cmd_locked(SEV_CMD_SNP_PLATFORM_STATUS, &buf, error); 2583 2584 if (sev->snp_initialized) { 2585 /* 2586 * The status page will be in Reclaim state on success, or left 2587 * in Firmware state on failure. Use snp_reclaim_pages() to 2588 * transition either case back to Hypervisor-owned state. 2589 */ 2590 if (snp_reclaim_pages(__pa(data), 1, true)) 2591 return -EFAULT; 2592 } 2593 2594 if (ret) 2595 goto cleanup; 2596 2597 memcpy(status, data, sizeof(*status)); 2598 2599 cleanup: 2600 __free_pages(status_page, 0); 2601 return ret; 2602 } 2603 2604 static int sev_ioctl_do_snp_platform_status(struct sev_issue_cmd *argp) 2605 { 2606 struct sev_user_data_snp_status status; 2607 int ret; 2608 2609 if (!argp->data) 2610 return -EINVAL; 2611 2612 ret = __sev_do_snp_platform_status(&status, &argp->error); 2613 if (ret < 0) 2614 return ret; 2615 2616 if (copy_to_user((void __user *)argp->data, &status, 2617 sizeof(struct sev_user_data_snp_status))) 2618 ret = -EFAULT; 2619 2620 return ret; 2621 } 2622 2623 static int sev_ioctl_do_snp_commit(struct sev_issue_cmd *argp) 2624 { 2625 struct sev_data_snp_commit buf; 2626 int ret; 2627 2628 buf.len = sizeof(buf); 2629 2630 ret = __sev_do_cmd_locked(SEV_CMD_SNP_COMMIT, &buf, &argp->error); 2631 2632 return ret; 2633 } 2634 2635 static int sev_ioctl_do_snp_set_config(struct sev_issue_cmd *argp, bool writable) 2636 { 2637 struct sev_device *sev = psp_master->sev_data; 2638 struct sev_user_data_snp_config config; 2639 2640 if (!argp->data) 2641 return -EINVAL; 2642 2643 if (!writable) 2644 return -EPERM; 2645 2646 if (!sev->snp_initialized) 2647 return -ENODEV; 2648 2649 if (copy_from_user(&config, (void __user *)argp->data, sizeof(config))) 2650 return -EFAULT; 2651 2652 return __sev_do_cmd_locked(SEV_CMD_SNP_CONFIG, &config, &argp->error); 2653 } 2654 2655 static int sev_ioctl_do_snp_vlek_load(struct sev_issue_cmd *argp, bool writable) 2656 { 2657 struct sev_device *sev = psp_master->sev_data; 2658 struct sev_user_data_snp_vlek_load input; 2659 void *blob; 2660 int ret; 2661 2662 if (!argp->data) 2663 return -EINVAL; 2664 2665 if (!writable) 2666 return -EPERM; 2667 2668 if (!sev->snp_initialized) 2669 return -ENODEV; 2670 2671 if (copy_from_user(&input, u64_to_user_ptr(argp->data), sizeof(input))) 2672 return -EFAULT; 2673 2674 if (input.len != sizeof(input) || input.vlek_wrapped_version != 0) 2675 return -EINVAL; 2676 2677 blob = psp_copy_user_blob(input.vlek_wrapped_address, 2678 sizeof(struct sev_user_data_snp_wrapped_vlek_hashstick)); 2679 if (IS_ERR(blob)) 2680 return PTR_ERR(blob); 2681 2682 input.vlek_wrapped_address = __psp_pa(blob); 2683 2684 ret = __sev_do_cmd_locked(SEV_CMD_SNP_VLEK_LOAD, &input, &argp->error); 2685 kfree(blob); 2686 2687 return ret; 2688 } 2689 2690 static long sev_ioctl(struct file *file, unsigned int ioctl, unsigned long arg) 2691 { 2692 void __user *argp = (void __user *)arg; 2693 struct sev_issue_cmd input; 2694 int ret = -EFAULT; 2695 bool writable = file->f_mode & FMODE_WRITE; 2696 2697 if (!psp_master || !psp_master->sev_data) 2698 return -ENODEV; 2699 2700 if (ioctl != SEV_ISSUE_CMD) 2701 return -EINVAL; 2702 2703 if (copy_from_user(&input, argp, sizeof(struct sev_issue_cmd))) 2704 return -EFAULT; 2705 2706 if (input.cmd > SEV_MAX) 2707 return -EINVAL; 2708 2709 mutex_lock(&sev_cmd_mutex); 2710 2711 switch (input.cmd) { 2712 2713 case SEV_FACTORY_RESET: 2714 ret = sev_ioctl_do_reset(&input, writable); 2715 break; 2716 case SEV_PLATFORM_STATUS: 2717 ret = sev_ioctl_do_platform_status(&input); 2718 break; 2719 case SEV_PEK_GEN: 2720 ret = sev_ioctl_do_pek_pdh_gen(SEV_CMD_PEK_GEN, &input, writable); 2721 break; 2722 case SEV_PDH_GEN: 2723 ret = sev_ioctl_do_pek_pdh_gen(SEV_CMD_PDH_GEN, &input, writable); 2724 break; 2725 case SEV_PEK_CSR: 2726 ret = sev_ioctl_do_pek_csr(&input, writable); 2727 break; 2728 case SEV_PEK_CERT_IMPORT: 2729 ret = sev_ioctl_do_pek_import(&input, writable); 2730 break; 2731 case SEV_PDH_CERT_EXPORT: 2732 ret = sev_ioctl_do_pdh_export(&input, writable); 2733 break; 2734 case SEV_GET_ID: 2735 pr_warn_once("SEV_GET_ID command is deprecated, use SEV_GET_ID2\n"); 2736 ret = sev_ioctl_do_get_id(&input); 2737 break; 2738 case SEV_GET_ID2: 2739 ret = sev_ioctl_do_get_id2(&input); 2740 break; 2741 case SNP_PLATFORM_STATUS: 2742 ret = sev_ioctl_do_snp_platform_status(&input); 2743 break; 2744 case SNP_COMMIT: 2745 ret = sev_ioctl_do_snp_commit(&input); 2746 break; 2747 case SNP_SET_CONFIG: 2748 ret = sev_ioctl_do_snp_set_config(&input, writable); 2749 break; 2750 case SNP_VLEK_LOAD: 2751 ret = sev_ioctl_do_snp_vlek_load(&input, writable); 2752 break; 2753 default: 2754 ret = -EINVAL; 2755 goto out; 2756 } 2757 2758 if (copy_to_user(argp, &input, sizeof(struct sev_issue_cmd))) 2759 ret = -EFAULT; 2760 out: 2761 mutex_unlock(&sev_cmd_mutex); 2762 2763 return ret; 2764 } 2765 2766 static const struct file_operations sev_fops = { 2767 .owner = THIS_MODULE, 2768 .unlocked_ioctl = sev_ioctl, 2769 }; 2770 2771 int sev_platform_status(struct sev_user_data_status *data, int *error) 2772 { 2773 return sev_do_cmd(SEV_CMD_PLATFORM_STATUS, data, error); 2774 } 2775 EXPORT_SYMBOL_GPL(sev_platform_status); 2776 2777 int sev_guest_deactivate(struct sev_data_deactivate *data, int *error) 2778 { 2779 return sev_do_cmd(SEV_CMD_DEACTIVATE, data, error); 2780 } 2781 EXPORT_SYMBOL_GPL(sev_guest_deactivate); 2782 2783 int sev_guest_activate(struct sev_data_activate *data, int *error) 2784 { 2785 return sev_do_cmd(SEV_CMD_ACTIVATE, data, error); 2786 } 2787 EXPORT_SYMBOL_GPL(sev_guest_activate); 2788 2789 int sev_guest_decommission(struct sev_data_decommission *data, int *error) 2790 { 2791 return sev_do_cmd(SEV_CMD_DECOMMISSION, data, error); 2792 } 2793 EXPORT_SYMBOL_GPL(sev_guest_decommission); 2794 2795 int sev_guest_df_flush(int *error) 2796 { 2797 return sev_do_cmd(SEV_CMD_DF_FLUSH, NULL, error); 2798 } 2799 EXPORT_SYMBOL_GPL(sev_guest_df_flush); 2800 2801 static void sev_exit(struct kref *ref) 2802 { 2803 misc_deregister(&misc_dev->misc); 2804 kfree(misc_dev); 2805 misc_dev = NULL; 2806 } 2807 2808 static int sev_misc_init(struct sev_device *sev) 2809 { 2810 struct device *dev = sev->dev; 2811 int ret; 2812 2813 /* 2814 * SEV feature support can be detected on multiple devices but the SEV 2815 * FW commands must be issued on the master. During probe, we do not 2816 * know the master hence we create /dev/sev on the first device probe. 2817 * sev_do_cmd() finds the right master device to which to issue the 2818 * command to the firmware. 2819 */ 2820 if (!misc_dev) { 2821 struct miscdevice *misc; 2822 2823 misc_dev = kzalloc_obj(*misc_dev); 2824 if (!misc_dev) 2825 return -ENOMEM; 2826 2827 misc = &misc_dev->misc; 2828 misc->minor = MISC_DYNAMIC_MINOR; 2829 misc->name = DEVICE_NAME; 2830 misc->fops = &sev_fops; 2831 2832 ret = misc_register(misc); 2833 if (ret) 2834 return ret; 2835 2836 kref_init(&misc_dev->refcount); 2837 } else { 2838 kref_get(&misc_dev->refcount); 2839 } 2840 2841 init_waitqueue_head(&sev->int_queue); 2842 sev->misc = misc_dev; 2843 dev_dbg(dev, "registered SEV device\n"); 2844 2845 return 0; 2846 } 2847 2848 int sev_dev_init(struct psp_device *psp) 2849 { 2850 struct device *dev = psp->dev; 2851 struct sev_device *sev; 2852 int ret = -ENOMEM; 2853 2854 if (!boot_cpu_has(X86_FEATURE_SEV)) { 2855 dev_info_once(dev, "SEV: memory encryption not enabled by BIOS\n"); 2856 return 0; 2857 } 2858 2859 sev = devm_kzalloc(dev, sizeof(*sev), GFP_KERNEL); 2860 if (!sev) 2861 goto e_err; 2862 2863 sev->cmd_buf = (void *)devm_get_free_pages(dev, GFP_KERNEL, 1); 2864 if (!sev->cmd_buf) 2865 goto e_sev; 2866 2867 sev->cmd_buf_backup = (uint8_t *)sev->cmd_buf + PAGE_SIZE; 2868 2869 psp->sev_data = sev; 2870 2871 sev->dev = dev; 2872 sev->psp = psp; 2873 2874 sev->io_regs = psp->io_regs; 2875 2876 sev->vdata = (struct sev_vdata *)psp->vdata->sev; 2877 if (!sev->vdata) { 2878 ret = -ENODEV; 2879 dev_err(dev, "sev: missing driver data\n"); 2880 goto e_buf; 2881 } 2882 2883 psp_set_sev_irq_handler(psp, sev_irq_handler, sev); 2884 2885 ret = sev_misc_init(sev); 2886 if (ret) 2887 goto e_irq; 2888 2889 dev_notice(dev, "sev enabled\n"); 2890 2891 return 0; 2892 2893 e_irq: 2894 psp_clear_sev_irq_handler(psp); 2895 e_buf: 2896 devm_free_pages(dev, (unsigned long)sev->cmd_buf); 2897 e_sev: 2898 devm_kfree(dev, sev); 2899 e_err: 2900 psp->sev_data = NULL; 2901 2902 dev_notice(dev, "sev initialization failed\n"); 2903 2904 return ret; 2905 } 2906 2907 static void __sev_firmware_shutdown(struct sev_device *sev, bool panic) 2908 { 2909 int error; 2910 2911 __sev_platform_shutdown_locked(&error); 2912 2913 if (sev_es_tmr) { 2914 /* 2915 * The TMR area was encrypted, flush it from the cache. 2916 * 2917 * If invoked during panic handling, local interrupts are 2918 * disabled and all CPUs are stopped, so wbinvd_on_all_cpus() 2919 * can't be used. In that case, wbinvd() is done on remote CPUs 2920 * via the NMI callback, and done for this CPU later during 2921 * SNP shutdown, so wbinvd_on_all_cpus() can be skipped. 2922 */ 2923 if (!panic) 2924 wbinvd_on_all_cpus(); 2925 2926 __snp_free_firmware_pages(virt_to_page(sev_es_tmr), 2927 get_order(sev_es_tmr_size), 2928 true); 2929 sev_es_tmr = NULL; 2930 } 2931 2932 if (sev_init_ex_buffer) { 2933 __snp_free_firmware_pages(virt_to_page(sev_init_ex_buffer), 2934 get_order(NV_LENGTH), 2935 true); 2936 sev_init_ex_buffer = NULL; 2937 } 2938 2939 __sev_snp_shutdown_locked(&error, panic); 2940 } 2941 2942 static void sev_firmware_shutdown(struct sev_device *sev) 2943 { 2944 /* 2945 * Calling without sev_cmd_mutex held as TSM will likely try disconnecting 2946 * IDE and this ends up calling sev_do_cmd() which locks sev_cmd_mutex. 2947 */ 2948 if (sev->tio_status) 2949 sev_tsm_uninit(sev); 2950 2951 /* 2952 * Remove the sysfs interface before taking the sev_cmd_mutex. 2953 * sysfs_remove_group() waits for in-flight _show()/_store() handlers 2954 * to drain, and those handlers issue SNP_VERIFY_MITIGATION via 2955 * sev_do_cmd() which acquires the sev_cmd_mutex. Removing the group 2956 * while holding the mutex could therefore deadlock. 2957 */ 2958 sev_snp_unregister_verify_mitigation(sev); 2959 2960 mutex_lock(&sev_cmd_mutex); 2961 2962 __sev_firmware_shutdown(sev, false); 2963 2964 kfree(sev->tio_status); 2965 sev->tio_status = NULL; 2966 2967 mutex_unlock(&sev_cmd_mutex); 2968 } 2969 2970 void sev_platform_shutdown(void) 2971 { 2972 if (!psp_master || !psp_master->sev_data) 2973 return; 2974 2975 sev_firmware_shutdown(psp_master->sev_data); 2976 } 2977 EXPORT_SYMBOL_GPL(sev_platform_shutdown); 2978 2979 u64 sev_get_snp_policy_bits(void) 2980 { 2981 struct psp_device *psp = psp_master; 2982 struct sev_device *sev; 2983 u64 policy_bits; 2984 2985 if (!cc_platform_has(CC_ATTR_HOST_SEV_SNP)) 2986 return 0; 2987 2988 if (!psp || !psp->sev_data) 2989 return 0; 2990 2991 sev = psp->sev_data; 2992 2993 policy_bits = SNP_POLICY_MASK_BASE; 2994 2995 if (sev->snp_plat_status.feature_info) { 2996 if (sev->snp_feat_info_0.ecx & SNP_RAPL_DISABLE_SUPPORTED) 2997 policy_bits |= SNP_POLICY_MASK_RAPL_DIS; 2998 2999 if (sev->snp_feat_info_0.ecx & SNP_CIPHER_TEXT_HIDING_SUPPORTED) 3000 policy_bits |= SNP_POLICY_MASK_CIPHERTEXT_HIDING_DRAM; 3001 3002 if (sev->snp_feat_info_0.ecx & SNP_AES_256_XTS_POLICY_SUPPORTED) 3003 policy_bits |= SNP_POLICY_MASK_MEM_AES_256_XTS; 3004 3005 if (sev->snp_feat_info_0.ecx & SNP_CXL_ALLOW_POLICY_SUPPORTED) 3006 policy_bits |= SNP_POLICY_MASK_CXL_ALLOW; 3007 3008 if (sev_version_greater_or_equal(1, 58)) 3009 policy_bits |= SNP_POLICY_MASK_PAGE_SWAP_DISABLE; 3010 } 3011 3012 return policy_bits; 3013 } 3014 EXPORT_SYMBOL_GPL(sev_get_snp_policy_bits); 3015 3016 void sev_dev_destroy(struct psp_device *psp) 3017 { 3018 struct sev_device *sev = psp->sev_data; 3019 3020 if (!sev) 3021 return; 3022 3023 sev_firmware_shutdown(sev); 3024 3025 if (sev->misc) 3026 kref_put(&misc_dev->refcount, sev_exit); 3027 3028 psp_clear_sev_irq_handler(psp); 3029 } 3030 3031 static int snp_shutdown_on_panic(struct notifier_block *nb, 3032 unsigned long reason, void *arg) 3033 { 3034 struct sev_device *sev = psp_master->sev_data; 3035 3036 /* 3037 * If sev_cmd_mutex is already acquired, then it's likely 3038 * another PSP command is in flight and issuing a shutdown 3039 * would fail in unexpected ways. Rather than create even 3040 * more confusion during a panic, just bail out here. 3041 */ 3042 if (mutex_is_locked(&sev_cmd_mutex)) 3043 return NOTIFY_DONE; 3044 3045 __sev_firmware_shutdown(sev, true); 3046 3047 return NOTIFY_DONE; 3048 } 3049 3050 int sev_issue_cmd_external_user(struct file *filep, unsigned int cmd, 3051 void *data, int *error) 3052 { 3053 if (!filep || filep->f_op != &sev_fops) 3054 return -EBADF; 3055 3056 return sev_do_cmd(cmd, data, error); 3057 } 3058 EXPORT_SYMBOL_GPL(sev_issue_cmd_external_user); 3059 3060 void sev_pci_init(void) 3061 { 3062 struct sev_device *sev = psp_master->sev_data; 3063 u8 api_major, api_minor, build; 3064 3065 if (!sev) 3066 return; 3067 3068 psp_timeout = psp_probe_timeout; 3069 3070 if (sev_get_api_version()) 3071 goto err; 3072 3073 api_major = sev->api_major; 3074 api_minor = sev->api_minor; 3075 build = sev->build; 3076 3077 if (sev_update_firmware(sev->dev) == 0) 3078 sev_get_api_version(); 3079 3080 if (api_major != sev->api_major || api_minor != sev->api_minor || 3081 build != sev->build) 3082 dev_info(sev->dev, "SEV firmware updated from %d.%d.%d to %d.%d.%d\n", 3083 api_major, api_minor, build, 3084 sev->api_major, sev->api_minor, sev->build); 3085 3086 return; 3087 3088 err: 3089 sev_dev_destroy(psp_master); 3090 3091 psp_master->sev_data = NULL; 3092 } 3093 3094 void sev_pci_exit(void) 3095 { 3096 struct sev_device *sev = psp_master->sev_data; 3097 3098 if (!sev) 3099 return; 3100 3101 sev_firmware_shutdown(sev); 3102 } 3103 3104 static int get_v1_svn(struct sev_device *sev) 3105 { 3106 struct sev_snp_tcb_version_genoa_milan *tcb; 3107 struct sev_user_data_snp_status status; 3108 int ret, error = 0; 3109 3110 mutex_lock(&sev_cmd_mutex); 3111 ret = __sev_do_snp_platform_status(&status, &error); 3112 mutex_unlock(&sev_cmd_mutex); 3113 if (ret < 0) 3114 return ret; 3115 3116 tcb = (struct sev_snp_tcb_version_genoa_milan *)&status 3117 .current_tcb_version; 3118 return tcb->snp; 3119 } 3120 3121 static int get_v2_svn(struct sev_device *sev) 3122 { 3123 struct sev_user_data_snp_status status; 3124 struct sev_snp_tcb_version_turin *tcb; 3125 int ret, error = 0; 3126 3127 mutex_lock(&sev_cmd_mutex); 3128 ret = __sev_do_snp_platform_status(&status, &error); 3129 mutex_unlock(&sev_cmd_mutex); 3130 if (ret < 0) 3131 return ret; 3132 3133 tcb = (struct sev_snp_tcb_version_turin *)&status 3134 .current_tcb_version; 3135 return tcb->snp; 3136 } 3137 3138 static bool sev_firmware_allows_es(struct sev_device *sev) 3139 { 3140 /* Documented in AMD-SB-3023 */ 3141 if (boot_cpu_has(X86_FEATURE_ZEN4) || boot_cpu_has(X86_FEATURE_ZEN3)) 3142 return get_v1_svn(sev) < 0x1b; 3143 else if (boot_cpu_has(X86_FEATURE_ZEN5)) 3144 return get_v2_svn(sev) < 0x4; 3145 else 3146 return true; 3147 } 3148 3149 int sev_firmware_supported_vm_types(void) 3150 { 3151 int supported_vm_types = 0; 3152 struct sev_device *sev; 3153 3154 if (!psp_master || !psp_master->sev_data) 3155 return supported_vm_types; 3156 sev = psp_master->sev_data; 3157 3158 supported_vm_types |= BIT(KVM_X86_SEV_VM); 3159 supported_vm_types |= BIT(KVM_X86_SEV_ES_VM); 3160 3161 if (!sev->snp_initialized) 3162 return supported_vm_types; 3163 3164 supported_vm_types |= BIT(KVM_X86_SNP_VM); 3165 3166 if (!sev_firmware_allows_es(sev)) 3167 supported_vm_types &= ~BIT(KVM_X86_SEV_ES_VM); 3168 3169 return supported_vm_types; 3170 3171 } 3172 EXPORT_SYMBOL_FOR_MODULES(sev_firmware_supported_vm_types, "kvm-amd"); 3173