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