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