1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Copyright(c) 2023 Intel Corporation. 4 * 5 * Intel Trusted Domain Extensions (TDX) support 6 */ 7 8 #include "asm/page_types.h" 9 #define pr_fmt(fmt) "virt/tdx: " fmt 10 11 #include <linux/types.h> 12 #include <linux/cache.h> 13 #include <linux/init.h> 14 #include <linux/errno.h> 15 #include <linux/printk.h> 16 #include <linux/cpu.h> 17 #include <linux/spinlock.h> 18 #include <linux/percpu-defs.h> 19 #include <linux/mutex.h> 20 #include <linux/list.h> 21 #include <linux/memblock.h> 22 #include <linux/memory.h> 23 #include <linux/minmax.h> 24 #include <linux/sizes.h> 25 #include <linux/pfn.h> 26 #include <linux/align.h> 27 #include <linux/sort.h> 28 #include <linux/log2.h> 29 #include <linux/acpi.h> 30 #include <linux/suspend.h> 31 #include <linux/idr.h> 32 #include <asm/page.h> 33 #include <asm/special_insns.h> 34 #include <asm/msr-index.h> 35 #include <asm/msr.h> 36 #include <asm/cpufeature.h> 37 #include <asm/tdx.h> 38 #include <asm/cpu_device_id.h> 39 #include <asm/processor.h> 40 #include <asm/mce.h> 41 #include "tdx.h" 42 43 static u32 tdx_global_keyid __ro_after_init; 44 static u32 tdx_guest_keyid_start __ro_after_init; 45 static u32 tdx_nr_guest_keyids __ro_after_init; 46 47 static DEFINE_IDA(tdx_guest_keyid_pool); 48 49 static DEFINE_PER_CPU(bool, tdx_lp_initialized); 50 51 static struct tdmr_info_list tdx_tdmr_list; 52 53 static enum tdx_module_status_t tdx_module_status; 54 static DEFINE_MUTEX(tdx_module_lock); 55 56 /* All TDX-usable memory regions. Protected by mem_hotplug_lock. */ 57 static LIST_HEAD(tdx_memlist); 58 59 static struct tdx_sys_info tdx_sysinfo; 60 61 typedef void (*sc_err_func_t)(u64 fn, u64 err, struct tdx_module_args *args); 62 63 static inline void seamcall_err(u64 fn, u64 err, struct tdx_module_args *args) 64 { 65 pr_err("SEAMCALL (0x%016llx) failed: 0x%016llx\n", fn, err); 66 } 67 68 static inline void seamcall_err_ret(u64 fn, u64 err, 69 struct tdx_module_args *args) 70 { 71 seamcall_err(fn, err, args); 72 pr_err("RCX 0x%016llx RDX 0x%016llx R08 0x%016llx\n", 73 args->rcx, args->rdx, args->r8); 74 pr_err("R09 0x%016llx R10 0x%016llx R11 0x%016llx\n", 75 args->r9, args->r10, args->r11); 76 } 77 78 static __always_inline int sc_retry_prerr(sc_func_t func, 79 sc_err_func_t err_func, 80 u64 fn, struct tdx_module_args *args) 81 { 82 u64 sret = sc_retry(func, fn, args); 83 84 if (sret == TDX_SUCCESS) 85 return 0; 86 87 if (sret == TDX_SEAMCALL_VMFAILINVALID) 88 return -ENODEV; 89 90 if (sret == TDX_SEAMCALL_GP) 91 return -EOPNOTSUPP; 92 93 if (sret == TDX_SEAMCALL_UD) 94 return -EACCES; 95 96 err_func(fn, sret, args); 97 return -EIO; 98 } 99 100 #define seamcall_prerr(__fn, __args) \ 101 sc_retry_prerr(__seamcall, seamcall_err, (__fn), (__args)) 102 103 #define seamcall_prerr_ret(__fn, __args) \ 104 sc_retry_prerr(__seamcall_ret, seamcall_err_ret, (__fn), (__args)) 105 106 /* 107 * Do the module global initialization once and return its result. 108 * It can be done on any cpu. It's always called with interrupts 109 * disabled. 110 */ 111 static int try_init_module_global(void) 112 { 113 struct tdx_module_args args = {}; 114 static DEFINE_RAW_SPINLOCK(sysinit_lock); 115 static bool sysinit_done; 116 static int sysinit_ret; 117 118 lockdep_assert_irqs_disabled(); 119 120 raw_spin_lock(&sysinit_lock); 121 122 if (sysinit_done) 123 goto out; 124 125 /* RCX is module attributes and all bits are reserved */ 126 args.rcx = 0; 127 sysinit_ret = seamcall_prerr(TDH_SYS_INIT, &args); 128 129 /* 130 * The first SEAMCALL also detects the TDX module, thus 131 * it can fail due to the TDX module is not loaded. 132 * Dump message to let the user know. 133 */ 134 if (sysinit_ret == -ENODEV) 135 pr_err("module not loaded\n"); 136 137 sysinit_done = true; 138 out: 139 raw_spin_unlock(&sysinit_lock); 140 return sysinit_ret; 141 } 142 143 /** 144 * tdx_cpu_enable - Enable TDX on local cpu 145 * 146 * Do one-time TDX module per-cpu initialization SEAMCALL (and TDX module 147 * global initialization SEAMCALL if not done) on local cpu to make this 148 * cpu be ready to run any other SEAMCALLs. 149 * 150 * Always call this function via IPI function calls. 151 * 152 * Return 0 on success, otherwise errors. 153 */ 154 int tdx_cpu_enable(void) 155 { 156 struct tdx_module_args args = {}; 157 int ret; 158 159 if (!boot_cpu_has(X86_FEATURE_TDX_HOST_PLATFORM)) 160 return -ENODEV; 161 162 lockdep_assert_irqs_disabled(); 163 164 if (__this_cpu_read(tdx_lp_initialized)) 165 return 0; 166 167 /* 168 * The TDX module global initialization is the very first step 169 * to enable TDX. Need to do it first (if hasn't been done) 170 * before the per-cpu initialization. 171 */ 172 ret = try_init_module_global(); 173 if (ret) 174 return ret; 175 176 ret = seamcall_prerr(TDH_SYS_LP_INIT, &args); 177 if (ret) 178 return ret; 179 180 __this_cpu_write(tdx_lp_initialized, true); 181 182 return 0; 183 } 184 EXPORT_SYMBOL_GPL(tdx_cpu_enable); 185 186 /* 187 * Add a memory region as a TDX memory block. The caller must make sure 188 * all memory regions are added in address ascending order and don't 189 * overlap. 190 */ 191 static int add_tdx_memblock(struct list_head *tmb_list, unsigned long start_pfn, 192 unsigned long end_pfn, int nid) 193 { 194 struct tdx_memblock *tmb; 195 196 tmb = kmalloc(sizeof(*tmb), GFP_KERNEL); 197 if (!tmb) 198 return -ENOMEM; 199 200 INIT_LIST_HEAD(&tmb->list); 201 tmb->start_pfn = start_pfn; 202 tmb->end_pfn = end_pfn; 203 tmb->nid = nid; 204 205 /* @tmb_list is protected by mem_hotplug_lock */ 206 list_add_tail(&tmb->list, tmb_list); 207 return 0; 208 } 209 210 static void free_tdx_memlist(struct list_head *tmb_list) 211 { 212 /* @tmb_list is protected by mem_hotplug_lock */ 213 while (!list_empty(tmb_list)) { 214 struct tdx_memblock *tmb = list_first_entry(tmb_list, 215 struct tdx_memblock, list); 216 217 list_del(&tmb->list); 218 kfree(tmb); 219 } 220 } 221 222 /* 223 * Ensure that all memblock memory regions are convertible to TDX 224 * memory. Once this has been established, stash the memblock 225 * ranges off in a secondary structure because memblock is modified 226 * in memory hotplug while TDX memory regions are fixed. 227 */ 228 static int build_tdx_memlist(struct list_head *tmb_list) 229 { 230 unsigned long start_pfn, end_pfn; 231 int i, nid, ret; 232 233 for_each_mem_pfn_range(i, MAX_NUMNODES, &start_pfn, &end_pfn, &nid) { 234 /* 235 * The first 1MB is not reported as TDX convertible memory. 236 * Although the first 1MB is always reserved and won't end up 237 * to the page allocator, it is still in memblock's memory 238 * regions. Skip them manually to exclude them as TDX memory. 239 */ 240 start_pfn = max(start_pfn, PHYS_PFN(SZ_1M)); 241 if (start_pfn >= end_pfn) 242 continue; 243 244 /* 245 * Add the memory regions as TDX memory. The regions in 246 * memblock has already guaranteed they are in address 247 * ascending order and don't overlap. 248 */ 249 ret = add_tdx_memblock(tmb_list, start_pfn, end_pfn, nid); 250 if (ret) 251 goto err; 252 } 253 254 return 0; 255 err: 256 free_tdx_memlist(tmb_list); 257 return ret; 258 } 259 260 static int read_sys_metadata_field(u64 field_id, u64 *data) 261 { 262 struct tdx_module_args args = {}; 263 int ret; 264 265 /* 266 * TDH.SYS.RD -- reads one global metadata field 267 * - RDX (in): the field to read 268 * - R8 (out): the field data 269 */ 270 args.rdx = field_id; 271 ret = seamcall_prerr_ret(TDH_SYS_RD, &args); 272 if (ret) 273 return ret; 274 275 *data = args.r8; 276 277 return 0; 278 } 279 280 #include "tdx_global_metadata.c" 281 282 static int check_features(struct tdx_sys_info *sysinfo) 283 { 284 u64 tdx_features0 = sysinfo->features.tdx_features0; 285 286 if (!(tdx_features0 & TDX_FEATURES0_NO_RBP_MOD)) { 287 pr_err("frame pointer (RBP) clobber bug present, upgrade TDX module\n"); 288 return -EINVAL; 289 } 290 291 return 0; 292 } 293 294 /* Calculate the actual TDMR size */ 295 static int tdmr_size_single(u16 max_reserved_per_tdmr) 296 { 297 int tdmr_sz; 298 299 /* 300 * The actual size of TDMR depends on the maximum 301 * number of reserved areas. 302 */ 303 tdmr_sz = sizeof(struct tdmr_info); 304 tdmr_sz += sizeof(struct tdmr_reserved_area) * max_reserved_per_tdmr; 305 306 return ALIGN(tdmr_sz, TDMR_INFO_ALIGNMENT); 307 } 308 309 static int alloc_tdmr_list(struct tdmr_info_list *tdmr_list, 310 struct tdx_sys_info_tdmr *sysinfo_tdmr) 311 { 312 size_t tdmr_sz, tdmr_array_sz; 313 void *tdmr_array; 314 315 tdmr_sz = tdmr_size_single(sysinfo_tdmr->max_reserved_per_tdmr); 316 tdmr_array_sz = tdmr_sz * sysinfo_tdmr->max_tdmrs; 317 318 /* 319 * To keep things simple, allocate all TDMRs together. 320 * The buffer needs to be physically contiguous to make 321 * sure each TDMR is physically contiguous. 322 */ 323 tdmr_array = alloc_pages_exact(tdmr_array_sz, 324 GFP_KERNEL | __GFP_ZERO); 325 if (!tdmr_array) 326 return -ENOMEM; 327 328 tdmr_list->tdmrs = tdmr_array; 329 330 /* 331 * Keep the size of TDMR to find the target TDMR 332 * at a given index in the TDMR list. 333 */ 334 tdmr_list->tdmr_sz = tdmr_sz; 335 tdmr_list->max_tdmrs = sysinfo_tdmr->max_tdmrs; 336 tdmr_list->nr_consumed_tdmrs = 0; 337 338 return 0; 339 } 340 341 static void free_tdmr_list(struct tdmr_info_list *tdmr_list) 342 { 343 free_pages_exact(tdmr_list->tdmrs, 344 tdmr_list->max_tdmrs * tdmr_list->tdmr_sz); 345 } 346 347 /* Get the TDMR from the list at the given index. */ 348 static struct tdmr_info *tdmr_entry(struct tdmr_info_list *tdmr_list, 349 int idx) 350 { 351 int tdmr_info_offset = tdmr_list->tdmr_sz * idx; 352 353 return (void *)tdmr_list->tdmrs + tdmr_info_offset; 354 } 355 356 #define TDMR_ALIGNMENT SZ_1G 357 #define TDMR_ALIGN_DOWN(_addr) ALIGN_DOWN((_addr), TDMR_ALIGNMENT) 358 #define TDMR_ALIGN_UP(_addr) ALIGN((_addr), TDMR_ALIGNMENT) 359 360 static inline u64 tdmr_end(struct tdmr_info *tdmr) 361 { 362 return tdmr->base + tdmr->size; 363 } 364 365 /* 366 * Take the memory referenced in @tmb_list and populate the 367 * preallocated @tdmr_list, following all the special alignment 368 * and size rules for TDMR. 369 */ 370 static int fill_out_tdmrs(struct list_head *tmb_list, 371 struct tdmr_info_list *tdmr_list) 372 { 373 struct tdx_memblock *tmb; 374 int tdmr_idx = 0; 375 376 /* 377 * Loop over TDX memory regions and fill out TDMRs to cover them. 378 * To keep it simple, always try to use one TDMR to cover one 379 * memory region. 380 * 381 * In practice TDX supports at least 64 TDMRs. A 2-socket system 382 * typically only consumes less than 10 of those. This code is 383 * dumb and simple and may use more TMDRs than is strictly 384 * required. 385 */ 386 list_for_each_entry(tmb, tmb_list, list) { 387 struct tdmr_info *tdmr = tdmr_entry(tdmr_list, tdmr_idx); 388 u64 start, end; 389 390 start = TDMR_ALIGN_DOWN(PFN_PHYS(tmb->start_pfn)); 391 end = TDMR_ALIGN_UP(PFN_PHYS(tmb->end_pfn)); 392 393 /* 394 * A valid size indicates the current TDMR has already 395 * been filled out to cover the previous memory region(s). 396 */ 397 if (tdmr->size) { 398 /* 399 * Loop to the next if the current memory region 400 * has already been fully covered. 401 */ 402 if (end <= tdmr_end(tdmr)) 403 continue; 404 405 /* Otherwise, skip the already covered part. */ 406 if (start < tdmr_end(tdmr)) 407 start = tdmr_end(tdmr); 408 409 /* 410 * Create a new TDMR to cover the current memory 411 * region, or the remaining part of it. 412 */ 413 tdmr_idx++; 414 if (tdmr_idx >= tdmr_list->max_tdmrs) { 415 pr_warn("initialization failed: TDMRs exhausted.\n"); 416 return -ENOSPC; 417 } 418 419 tdmr = tdmr_entry(tdmr_list, tdmr_idx); 420 } 421 422 tdmr->base = start; 423 tdmr->size = end - start; 424 } 425 426 /* @tdmr_idx is always the index of the last valid TDMR. */ 427 tdmr_list->nr_consumed_tdmrs = tdmr_idx + 1; 428 429 /* 430 * Warn early that kernel is about to run out of TDMRs. 431 * 432 * This is an indication that TDMR allocation has to be 433 * reworked to be smarter to not run into an issue. 434 */ 435 if (tdmr_list->max_tdmrs - tdmr_list->nr_consumed_tdmrs < TDMR_NR_WARN) 436 pr_warn("consumed TDMRs reaching limit: %d used out of %d\n", 437 tdmr_list->nr_consumed_tdmrs, 438 tdmr_list->max_tdmrs); 439 440 return 0; 441 } 442 443 /* 444 * Calculate PAMT size given a TDMR and a page size. The returned 445 * PAMT size is always aligned up to 4K page boundary. 446 */ 447 static unsigned long tdmr_get_pamt_sz(struct tdmr_info *tdmr, int pgsz, 448 u16 pamt_entry_size) 449 { 450 unsigned long pamt_sz, nr_pamt_entries; 451 452 switch (pgsz) { 453 case TDX_PS_4K: 454 nr_pamt_entries = tdmr->size >> PAGE_SHIFT; 455 break; 456 case TDX_PS_2M: 457 nr_pamt_entries = tdmr->size >> PMD_SHIFT; 458 break; 459 case TDX_PS_1G: 460 nr_pamt_entries = tdmr->size >> PUD_SHIFT; 461 break; 462 default: 463 WARN_ON_ONCE(1); 464 return 0; 465 } 466 467 pamt_sz = nr_pamt_entries * pamt_entry_size; 468 /* TDX requires PAMT size must be 4K aligned */ 469 pamt_sz = ALIGN(pamt_sz, PAGE_SIZE); 470 471 return pamt_sz; 472 } 473 474 /* 475 * Locate a NUMA node which should hold the allocation of the @tdmr 476 * PAMT. This node will have some memory covered by the TDMR. The 477 * relative amount of memory covered is not considered. 478 */ 479 static int tdmr_get_nid(struct tdmr_info *tdmr, struct list_head *tmb_list) 480 { 481 struct tdx_memblock *tmb; 482 483 /* 484 * A TDMR must cover at least part of one TMB. That TMB will end 485 * after the TDMR begins. But, that TMB may have started before 486 * the TDMR. Find the next 'tmb' that _ends_ after this TDMR 487 * begins. Ignore 'tmb' start addresses. They are irrelevant. 488 */ 489 list_for_each_entry(tmb, tmb_list, list) { 490 if (tmb->end_pfn > PHYS_PFN(tdmr->base)) 491 return tmb->nid; 492 } 493 494 /* 495 * Fall back to allocating the TDMR's metadata from node 0 when 496 * no TDX memory block can be found. This should never happen 497 * since TDMRs originate from TDX memory blocks. 498 */ 499 pr_warn("TDMR [0x%llx, 0x%llx): unable to find local NUMA node for PAMT allocation, fallback to use node 0.\n", 500 tdmr->base, tdmr_end(tdmr)); 501 return 0; 502 } 503 504 /* 505 * Allocate PAMTs from the local NUMA node of some memory in @tmb_list 506 * within @tdmr, and set up PAMTs for @tdmr. 507 */ 508 static int tdmr_set_up_pamt(struct tdmr_info *tdmr, 509 struct list_head *tmb_list, 510 u16 pamt_entry_size[]) 511 { 512 unsigned long pamt_base[TDX_PS_NR]; 513 unsigned long pamt_size[TDX_PS_NR]; 514 unsigned long tdmr_pamt_base; 515 unsigned long tdmr_pamt_size; 516 struct page *pamt; 517 int pgsz, nid; 518 519 nid = tdmr_get_nid(tdmr, tmb_list); 520 521 /* 522 * Calculate the PAMT size for each TDX supported page size 523 * and the total PAMT size. 524 */ 525 tdmr_pamt_size = 0; 526 for (pgsz = TDX_PS_4K; pgsz < TDX_PS_NR; pgsz++) { 527 pamt_size[pgsz] = tdmr_get_pamt_sz(tdmr, pgsz, 528 pamt_entry_size[pgsz]); 529 tdmr_pamt_size += pamt_size[pgsz]; 530 } 531 532 /* 533 * Allocate one chunk of physically contiguous memory for all 534 * PAMTs. This helps minimize the PAMT's use of reserved areas 535 * in overlapped TDMRs. 536 */ 537 pamt = alloc_contig_pages(tdmr_pamt_size >> PAGE_SHIFT, GFP_KERNEL, 538 nid, &node_online_map); 539 if (!pamt) 540 return -ENOMEM; 541 542 /* 543 * Break the contiguous allocation back up into the 544 * individual PAMTs for each page size. 545 */ 546 tdmr_pamt_base = page_to_pfn(pamt) << PAGE_SHIFT; 547 for (pgsz = TDX_PS_4K; pgsz < TDX_PS_NR; pgsz++) { 548 pamt_base[pgsz] = tdmr_pamt_base; 549 tdmr_pamt_base += pamt_size[pgsz]; 550 } 551 552 tdmr->pamt_4k_base = pamt_base[TDX_PS_4K]; 553 tdmr->pamt_4k_size = pamt_size[TDX_PS_4K]; 554 tdmr->pamt_2m_base = pamt_base[TDX_PS_2M]; 555 tdmr->pamt_2m_size = pamt_size[TDX_PS_2M]; 556 tdmr->pamt_1g_base = pamt_base[TDX_PS_1G]; 557 tdmr->pamt_1g_size = pamt_size[TDX_PS_1G]; 558 559 return 0; 560 } 561 562 static void tdmr_get_pamt(struct tdmr_info *tdmr, unsigned long *pamt_base, 563 unsigned long *pamt_size) 564 { 565 unsigned long pamt_bs, pamt_sz; 566 567 /* 568 * The PAMT was allocated in one contiguous unit. The 4K PAMT 569 * should always point to the beginning of that allocation. 570 */ 571 pamt_bs = tdmr->pamt_4k_base; 572 pamt_sz = tdmr->pamt_4k_size + tdmr->pamt_2m_size + tdmr->pamt_1g_size; 573 574 WARN_ON_ONCE((pamt_bs & ~PAGE_MASK) || (pamt_sz & ~PAGE_MASK)); 575 576 *pamt_base = pamt_bs; 577 *pamt_size = pamt_sz; 578 } 579 580 static void tdmr_do_pamt_func(struct tdmr_info *tdmr, 581 void (*pamt_func)(unsigned long base, unsigned long size)) 582 { 583 unsigned long pamt_base, pamt_size; 584 585 tdmr_get_pamt(tdmr, &pamt_base, &pamt_size); 586 587 /* Do nothing if PAMT hasn't been allocated for this TDMR */ 588 if (!pamt_size) 589 return; 590 591 if (WARN_ON_ONCE(!pamt_base)) 592 return; 593 594 pamt_func(pamt_base, pamt_size); 595 } 596 597 static void free_pamt(unsigned long pamt_base, unsigned long pamt_size) 598 { 599 free_contig_range(pamt_base >> PAGE_SHIFT, pamt_size >> PAGE_SHIFT); 600 } 601 602 static void tdmr_free_pamt(struct tdmr_info *tdmr) 603 { 604 tdmr_do_pamt_func(tdmr, free_pamt); 605 } 606 607 static void tdmrs_free_pamt_all(struct tdmr_info_list *tdmr_list) 608 { 609 int i; 610 611 for (i = 0; i < tdmr_list->nr_consumed_tdmrs; i++) 612 tdmr_free_pamt(tdmr_entry(tdmr_list, i)); 613 } 614 615 /* Allocate and set up PAMTs for all TDMRs */ 616 static int tdmrs_set_up_pamt_all(struct tdmr_info_list *tdmr_list, 617 struct list_head *tmb_list, 618 u16 pamt_entry_size[]) 619 { 620 int i, ret = 0; 621 622 for (i = 0; i < tdmr_list->nr_consumed_tdmrs; i++) { 623 ret = tdmr_set_up_pamt(tdmr_entry(tdmr_list, i), tmb_list, 624 pamt_entry_size); 625 if (ret) 626 goto err; 627 } 628 629 return 0; 630 err: 631 tdmrs_free_pamt_all(tdmr_list); 632 return ret; 633 } 634 635 /* 636 * Convert TDX private pages back to normal by using MOVDIR64B to 637 * clear these pages. Note this function doesn't flush cache of 638 * these TDX private pages. The caller should make sure of that. 639 */ 640 static void reset_tdx_pages(unsigned long base, unsigned long size) 641 { 642 const void *zero_page = (const void *)page_address(ZERO_PAGE(0)); 643 unsigned long phys, end; 644 645 end = base + size; 646 for (phys = base; phys < end; phys += 64) 647 movdir64b(__va(phys), zero_page); 648 649 /* 650 * MOVDIR64B uses WC protocol. Use memory barrier to 651 * make sure any later user of these pages sees the 652 * updated data. 653 */ 654 mb(); 655 } 656 657 static void tdmr_reset_pamt(struct tdmr_info *tdmr) 658 { 659 tdmr_do_pamt_func(tdmr, reset_tdx_pages); 660 } 661 662 static void tdmrs_reset_pamt_all(struct tdmr_info_list *tdmr_list) 663 { 664 int i; 665 666 for (i = 0; i < tdmr_list->nr_consumed_tdmrs; i++) 667 tdmr_reset_pamt(tdmr_entry(tdmr_list, i)); 668 } 669 670 static unsigned long tdmrs_count_pamt_kb(struct tdmr_info_list *tdmr_list) 671 { 672 unsigned long pamt_size = 0; 673 int i; 674 675 for (i = 0; i < tdmr_list->nr_consumed_tdmrs; i++) { 676 unsigned long base, size; 677 678 tdmr_get_pamt(tdmr_entry(tdmr_list, i), &base, &size); 679 pamt_size += size; 680 } 681 682 return pamt_size / 1024; 683 } 684 685 static int tdmr_add_rsvd_area(struct tdmr_info *tdmr, int *p_idx, u64 addr, 686 u64 size, u16 max_reserved_per_tdmr) 687 { 688 struct tdmr_reserved_area *rsvd_areas = tdmr->reserved_areas; 689 int idx = *p_idx; 690 691 /* Reserved area must be 4K aligned in offset and size */ 692 if (WARN_ON(addr & ~PAGE_MASK || size & ~PAGE_MASK)) 693 return -EINVAL; 694 695 if (idx >= max_reserved_per_tdmr) { 696 pr_warn("initialization failed: TDMR [0x%llx, 0x%llx): reserved areas exhausted.\n", 697 tdmr->base, tdmr_end(tdmr)); 698 return -ENOSPC; 699 } 700 701 /* 702 * Consume one reserved area per call. Make no effort to 703 * optimize or reduce the number of reserved areas which are 704 * consumed by contiguous reserved areas, for instance. 705 */ 706 rsvd_areas[idx].offset = addr - tdmr->base; 707 rsvd_areas[idx].size = size; 708 709 *p_idx = idx + 1; 710 711 return 0; 712 } 713 714 /* 715 * Go through @tmb_list to find holes between memory areas. If any of 716 * those holes fall within @tdmr, set up a TDMR reserved area to cover 717 * the hole. 718 */ 719 static int tdmr_populate_rsvd_holes(struct list_head *tmb_list, 720 struct tdmr_info *tdmr, 721 int *rsvd_idx, 722 u16 max_reserved_per_tdmr) 723 { 724 struct tdx_memblock *tmb; 725 u64 prev_end; 726 int ret; 727 728 /* 729 * Start looking for reserved blocks at the 730 * beginning of the TDMR. 731 */ 732 prev_end = tdmr->base; 733 list_for_each_entry(tmb, tmb_list, list) { 734 u64 start, end; 735 736 start = PFN_PHYS(tmb->start_pfn); 737 end = PFN_PHYS(tmb->end_pfn); 738 739 /* Break if this region is after the TDMR */ 740 if (start >= tdmr_end(tdmr)) 741 break; 742 743 /* Exclude regions before this TDMR */ 744 if (end < tdmr->base) 745 continue; 746 747 /* 748 * Skip over memory areas that 749 * have already been dealt with. 750 */ 751 if (start <= prev_end) { 752 prev_end = end; 753 continue; 754 } 755 756 /* Add the hole before this region */ 757 ret = tdmr_add_rsvd_area(tdmr, rsvd_idx, prev_end, 758 start - prev_end, 759 max_reserved_per_tdmr); 760 if (ret) 761 return ret; 762 763 prev_end = end; 764 } 765 766 /* Add the hole after the last region if it exists. */ 767 if (prev_end < tdmr_end(tdmr)) { 768 ret = tdmr_add_rsvd_area(tdmr, rsvd_idx, prev_end, 769 tdmr_end(tdmr) - prev_end, 770 max_reserved_per_tdmr); 771 if (ret) 772 return ret; 773 } 774 775 return 0; 776 } 777 778 /* 779 * Go through @tdmr_list to find all PAMTs. If any of those PAMTs 780 * overlaps with @tdmr, set up a TDMR reserved area to cover the 781 * overlapping part. 782 */ 783 static int tdmr_populate_rsvd_pamts(struct tdmr_info_list *tdmr_list, 784 struct tdmr_info *tdmr, 785 int *rsvd_idx, 786 u16 max_reserved_per_tdmr) 787 { 788 int i, ret; 789 790 for (i = 0; i < tdmr_list->nr_consumed_tdmrs; i++) { 791 struct tdmr_info *tmp = tdmr_entry(tdmr_list, i); 792 unsigned long pamt_base, pamt_size, pamt_end; 793 794 tdmr_get_pamt(tmp, &pamt_base, &pamt_size); 795 /* Each TDMR must already have PAMT allocated */ 796 WARN_ON_ONCE(!pamt_size || !pamt_base); 797 798 pamt_end = pamt_base + pamt_size; 799 /* Skip PAMTs outside of the given TDMR */ 800 if ((pamt_end <= tdmr->base) || 801 (pamt_base >= tdmr_end(tdmr))) 802 continue; 803 804 /* Only mark the part within the TDMR as reserved */ 805 if (pamt_base < tdmr->base) 806 pamt_base = tdmr->base; 807 if (pamt_end > tdmr_end(tdmr)) 808 pamt_end = tdmr_end(tdmr); 809 810 ret = tdmr_add_rsvd_area(tdmr, rsvd_idx, pamt_base, 811 pamt_end - pamt_base, 812 max_reserved_per_tdmr); 813 if (ret) 814 return ret; 815 } 816 817 return 0; 818 } 819 820 /* Compare function called by sort() for TDMR reserved areas */ 821 static int rsvd_area_cmp_func(const void *a, const void *b) 822 { 823 struct tdmr_reserved_area *r1 = (struct tdmr_reserved_area *)a; 824 struct tdmr_reserved_area *r2 = (struct tdmr_reserved_area *)b; 825 826 if (r1->offset + r1->size <= r2->offset) 827 return -1; 828 if (r1->offset >= r2->offset + r2->size) 829 return 1; 830 831 /* Reserved areas cannot overlap. The caller must guarantee. */ 832 WARN_ON_ONCE(1); 833 return -1; 834 } 835 836 /* 837 * Populate reserved areas for the given @tdmr, including memory holes 838 * (via @tmb_list) and PAMTs (via @tdmr_list). 839 */ 840 static int tdmr_populate_rsvd_areas(struct tdmr_info *tdmr, 841 struct list_head *tmb_list, 842 struct tdmr_info_list *tdmr_list, 843 u16 max_reserved_per_tdmr) 844 { 845 int ret, rsvd_idx = 0; 846 847 ret = tdmr_populate_rsvd_holes(tmb_list, tdmr, &rsvd_idx, 848 max_reserved_per_tdmr); 849 if (ret) 850 return ret; 851 852 ret = tdmr_populate_rsvd_pamts(tdmr_list, tdmr, &rsvd_idx, 853 max_reserved_per_tdmr); 854 if (ret) 855 return ret; 856 857 /* TDX requires reserved areas listed in address ascending order */ 858 sort(tdmr->reserved_areas, rsvd_idx, sizeof(struct tdmr_reserved_area), 859 rsvd_area_cmp_func, NULL); 860 861 return 0; 862 } 863 864 /* 865 * Populate reserved areas for all TDMRs in @tdmr_list, including memory 866 * holes (via @tmb_list) and PAMTs. 867 */ 868 static int tdmrs_populate_rsvd_areas_all(struct tdmr_info_list *tdmr_list, 869 struct list_head *tmb_list, 870 u16 max_reserved_per_tdmr) 871 { 872 int i; 873 874 for (i = 0; i < tdmr_list->nr_consumed_tdmrs; i++) { 875 int ret; 876 877 ret = tdmr_populate_rsvd_areas(tdmr_entry(tdmr_list, i), 878 tmb_list, tdmr_list, max_reserved_per_tdmr); 879 if (ret) 880 return ret; 881 } 882 883 return 0; 884 } 885 886 /* 887 * Construct a list of TDMRs on the preallocated space in @tdmr_list 888 * to cover all TDX memory regions in @tmb_list based on the TDX module 889 * TDMR global information in @sysinfo_tdmr. 890 */ 891 static int construct_tdmrs(struct list_head *tmb_list, 892 struct tdmr_info_list *tdmr_list, 893 struct tdx_sys_info_tdmr *sysinfo_tdmr) 894 { 895 u16 pamt_entry_size[TDX_PS_NR] = { 896 sysinfo_tdmr->pamt_4k_entry_size, 897 sysinfo_tdmr->pamt_2m_entry_size, 898 sysinfo_tdmr->pamt_1g_entry_size, 899 }; 900 int ret; 901 902 ret = fill_out_tdmrs(tmb_list, tdmr_list); 903 if (ret) 904 return ret; 905 906 ret = tdmrs_set_up_pamt_all(tdmr_list, tmb_list, pamt_entry_size); 907 if (ret) 908 return ret; 909 910 ret = tdmrs_populate_rsvd_areas_all(tdmr_list, tmb_list, 911 sysinfo_tdmr->max_reserved_per_tdmr); 912 if (ret) 913 tdmrs_free_pamt_all(tdmr_list); 914 915 /* 916 * The tdmr_info_list is read-only from here on out. 917 * Ensure that these writes are seen by other CPUs. 918 * Pairs with a smp_rmb() in is_pamt_page(). 919 */ 920 smp_wmb(); 921 922 return ret; 923 } 924 925 static int config_tdx_module(struct tdmr_info_list *tdmr_list, u64 global_keyid) 926 { 927 struct tdx_module_args args = {}; 928 u64 *tdmr_pa_array; 929 size_t array_sz; 930 int i, ret; 931 932 /* 933 * TDMRs are passed to the TDX module via an array of physical 934 * addresses of each TDMR. The array itself also has certain 935 * alignment requirement. 936 */ 937 array_sz = tdmr_list->nr_consumed_tdmrs * sizeof(u64); 938 array_sz = roundup_pow_of_two(array_sz); 939 if (array_sz < TDMR_INFO_PA_ARRAY_ALIGNMENT) 940 array_sz = TDMR_INFO_PA_ARRAY_ALIGNMENT; 941 942 tdmr_pa_array = kzalloc(array_sz, GFP_KERNEL); 943 if (!tdmr_pa_array) 944 return -ENOMEM; 945 946 for (i = 0; i < tdmr_list->nr_consumed_tdmrs; i++) 947 tdmr_pa_array[i] = __pa(tdmr_entry(tdmr_list, i)); 948 949 args.rcx = __pa(tdmr_pa_array); 950 args.rdx = tdmr_list->nr_consumed_tdmrs; 951 args.r8 = global_keyid; 952 ret = seamcall_prerr(TDH_SYS_CONFIG, &args); 953 954 /* Free the array as it is not required anymore. */ 955 kfree(tdmr_pa_array); 956 957 return ret; 958 } 959 960 static int do_global_key_config(void *unused) 961 { 962 struct tdx_module_args args = {}; 963 964 return seamcall_prerr(TDH_SYS_KEY_CONFIG, &args); 965 } 966 967 /* 968 * Attempt to configure the global KeyID on all physical packages. 969 * 970 * This requires running code on at least one CPU in each package. 971 * TDMR initialization) will fail will fail if any package in the 972 * system has no online CPUs. 973 * 974 * This code takes no affirmative steps to online CPUs. Callers (aka. 975 * KVM) can ensure success by ensuring sufficient CPUs are online and 976 * can run SEAMCALLs. 977 */ 978 static int config_global_keyid(void) 979 { 980 cpumask_var_t packages; 981 int cpu, ret = -EINVAL; 982 983 if (!zalloc_cpumask_var(&packages, GFP_KERNEL)) 984 return -ENOMEM; 985 986 /* 987 * Hardware doesn't guarantee cache coherency across different 988 * KeyIDs. The kernel needs to flush PAMT's dirty cachelines 989 * (associated with KeyID 0) before the TDX module can use the 990 * global KeyID to access the PAMT. Given PAMTs are potentially 991 * large (~1/256th of system RAM), just use WBINVD. 992 */ 993 wbinvd_on_all_cpus(); 994 995 for_each_online_cpu(cpu) { 996 /* 997 * The key configuration only needs to be done once per 998 * package and will return an error if configured more 999 * than once. Avoid doing it multiple times per package. 1000 */ 1001 if (cpumask_test_and_set_cpu(topology_physical_package_id(cpu), 1002 packages)) 1003 continue; 1004 1005 /* 1006 * TDH.SYS.KEY.CONFIG cannot run concurrently on 1007 * different cpus. Do it one by one. 1008 */ 1009 ret = smp_call_on_cpu(cpu, do_global_key_config, NULL, true); 1010 if (ret) 1011 break; 1012 } 1013 1014 free_cpumask_var(packages); 1015 return ret; 1016 } 1017 1018 static int init_tdmr(struct tdmr_info *tdmr) 1019 { 1020 u64 next; 1021 1022 /* 1023 * Initializing a TDMR can be time consuming. To avoid long 1024 * SEAMCALLs, the TDX module may only initialize a part of the 1025 * TDMR in each call. 1026 */ 1027 do { 1028 struct tdx_module_args args = { 1029 .rcx = tdmr->base, 1030 }; 1031 int ret; 1032 1033 ret = seamcall_prerr_ret(TDH_SYS_TDMR_INIT, &args); 1034 if (ret) 1035 return ret; 1036 /* 1037 * RDX contains 'next-to-initialize' address if 1038 * TDH.SYS.TDMR.INIT did not fully complete and 1039 * should be retried. 1040 */ 1041 next = args.rdx; 1042 cond_resched(); 1043 /* Keep making SEAMCALLs until the TDMR is done */ 1044 } while (next < tdmr->base + tdmr->size); 1045 1046 return 0; 1047 } 1048 1049 static int init_tdmrs(struct tdmr_info_list *tdmr_list) 1050 { 1051 int i; 1052 1053 /* 1054 * This operation is costly. It can be parallelized, 1055 * but keep it simple for now. 1056 */ 1057 for (i = 0; i < tdmr_list->nr_consumed_tdmrs; i++) { 1058 int ret; 1059 1060 ret = init_tdmr(tdmr_entry(tdmr_list, i)); 1061 if (ret) 1062 return ret; 1063 } 1064 1065 return 0; 1066 } 1067 1068 static int init_tdx_module(void) 1069 { 1070 int ret; 1071 1072 ret = get_tdx_sys_info(&tdx_sysinfo); 1073 if (ret) 1074 return ret; 1075 1076 /* Check whether the kernel can support this module */ 1077 ret = check_features(&tdx_sysinfo); 1078 if (ret) 1079 return ret; 1080 1081 /* 1082 * To keep things simple, assume that all TDX-protected memory 1083 * will come from the page allocator. Make sure all pages in the 1084 * page allocator are TDX-usable memory. 1085 * 1086 * Build the list of "TDX-usable" memory regions which cover all 1087 * pages in the page allocator to guarantee that. Do it while 1088 * holding mem_hotplug_lock read-lock as the memory hotplug code 1089 * path reads the @tdx_memlist to reject any new memory. 1090 */ 1091 get_online_mems(); 1092 1093 ret = build_tdx_memlist(&tdx_memlist); 1094 if (ret) 1095 goto out_put_tdxmem; 1096 1097 /* Allocate enough space for constructing TDMRs */ 1098 ret = alloc_tdmr_list(&tdx_tdmr_list, &tdx_sysinfo.tdmr); 1099 if (ret) 1100 goto err_free_tdxmem; 1101 1102 /* Cover all TDX-usable memory regions in TDMRs */ 1103 ret = construct_tdmrs(&tdx_memlist, &tdx_tdmr_list, &tdx_sysinfo.tdmr); 1104 if (ret) 1105 goto err_free_tdmrs; 1106 1107 /* Pass the TDMRs and the global KeyID to the TDX module */ 1108 ret = config_tdx_module(&tdx_tdmr_list, tdx_global_keyid); 1109 if (ret) 1110 goto err_free_pamts; 1111 1112 /* Config the key of global KeyID on all packages */ 1113 ret = config_global_keyid(); 1114 if (ret) 1115 goto err_reset_pamts; 1116 1117 /* Initialize TDMRs to complete the TDX module initialization */ 1118 ret = init_tdmrs(&tdx_tdmr_list); 1119 if (ret) 1120 goto err_reset_pamts; 1121 1122 pr_info("%lu KB allocated for PAMT\n", tdmrs_count_pamt_kb(&tdx_tdmr_list)); 1123 1124 out_put_tdxmem: 1125 /* 1126 * @tdx_memlist is written here and read at memory hotplug time. 1127 * Lock out memory hotplug code while building it. 1128 */ 1129 put_online_mems(); 1130 return ret; 1131 1132 err_reset_pamts: 1133 /* 1134 * Part of PAMTs may already have been initialized by the 1135 * TDX module. Flush cache before returning PAMTs back 1136 * to the kernel. 1137 */ 1138 wbinvd_on_all_cpus(); 1139 /* 1140 * According to the TDX hardware spec, if the platform 1141 * doesn't have the "partial write machine check" 1142 * erratum, any kernel read/write will never cause #MC 1143 * in kernel space, thus it's OK to not convert PAMTs 1144 * back to normal. But do the conversion anyway here 1145 * as suggested by the TDX spec. 1146 */ 1147 tdmrs_reset_pamt_all(&tdx_tdmr_list); 1148 err_free_pamts: 1149 tdmrs_free_pamt_all(&tdx_tdmr_list); 1150 err_free_tdmrs: 1151 free_tdmr_list(&tdx_tdmr_list); 1152 err_free_tdxmem: 1153 free_tdx_memlist(&tdx_memlist); 1154 goto out_put_tdxmem; 1155 } 1156 1157 static int __tdx_enable(void) 1158 { 1159 int ret; 1160 1161 ret = init_tdx_module(); 1162 if (ret) { 1163 pr_err("module initialization failed (%d)\n", ret); 1164 tdx_module_status = TDX_MODULE_ERROR; 1165 return ret; 1166 } 1167 1168 pr_info("module initialized\n"); 1169 tdx_module_status = TDX_MODULE_INITIALIZED; 1170 1171 return 0; 1172 } 1173 1174 /** 1175 * tdx_enable - Enable TDX module to make it ready to run TDX guests 1176 * 1177 * This function assumes the caller has: 1) held read lock of CPU hotplug 1178 * lock to prevent any new cpu from becoming online; 2) done both VMXON 1179 * and tdx_cpu_enable() on all online cpus. 1180 * 1181 * This function requires there's at least one online cpu for each CPU 1182 * package to succeed. 1183 * 1184 * This function can be called in parallel by multiple callers. 1185 * 1186 * Return 0 if TDX is enabled successfully, otherwise error. 1187 */ 1188 int tdx_enable(void) 1189 { 1190 int ret; 1191 1192 if (!boot_cpu_has(X86_FEATURE_TDX_HOST_PLATFORM)) 1193 return -ENODEV; 1194 1195 lockdep_assert_cpus_held(); 1196 1197 mutex_lock(&tdx_module_lock); 1198 1199 switch (tdx_module_status) { 1200 case TDX_MODULE_UNINITIALIZED: 1201 ret = __tdx_enable(); 1202 break; 1203 case TDX_MODULE_INITIALIZED: 1204 /* Already initialized, great, tell the caller. */ 1205 ret = 0; 1206 break; 1207 default: 1208 /* Failed to initialize in the previous attempts */ 1209 ret = -EINVAL; 1210 break; 1211 } 1212 1213 mutex_unlock(&tdx_module_lock); 1214 1215 return ret; 1216 } 1217 EXPORT_SYMBOL_GPL(tdx_enable); 1218 1219 static bool is_pamt_page(unsigned long phys) 1220 { 1221 struct tdmr_info_list *tdmr_list = &tdx_tdmr_list; 1222 int i; 1223 1224 /* Ensure that all remote 'tdmr_list' writes are visible: */ 1225 smp_rmb(); 1226 1227 /* 1228 * The TDX module is no longer returning TDX_SYS_NOT_READY and 1229 * is initialized. The 'tdmr_list' was initialized long ago 1230 * and is now read-only. 1231 */ 1232 for (i = 0; i < tdmr_list->nr_consumed_tdmrs; i++) { 1233 unsigned long base, size; 1234 1235 tdmr_get_pamt(tdmr_entry(tdmr_list, i), &base, &size); 1236 1237 if (phys >= base && phys < (base + size)) 1238 return true; 1239 } 1240 1241 return false; 1242 } 1243 1244 /* 1245 * Return whether the memory page at the given physical address is TDX 1246 * private memory or not. 1247 * 1248 * This can be imprecise for two known reasons: 1249 * 1. PAMTs are private memory and exist before the TDX module is 1250 * ready and TDH_PHYMEM_PAGE_RDMD works. This is a relatively 1251 * short window that occurs once per boot. 1252 * 2. TDH_PHYMEM_PAGE_RDMD reflects the TDX module's knowledge of the 1253 * page. However, the page can still cause #MC until it has been 1254 * fully converted to shared using 64-byte writes like MOVDIR64B. 1255 * Buggy hosts might still leave #MC-causing memory in place which 1256 * this function can not detect. 1257 */ 1258 static bool paddr_is_tdx_private(unsigned long phys) 1259 { 1260 struct tdx_module_args args = { 1261 .rcx = phys & PAGE_MASK, 1262 }; 1263 u64 sret; 1264 1265 if (!boot_cpu_has(X86_FEATURE_TDX_HOST_PLATFORM)) 1266 return false; 1267 1268 /* Get page type from the TDX module */ 1269 sret = __seamcall_ret(TDH_PHYMEM_PAGE_RDMD, &args); 1270 1271 /* 1272 * The SEAMCALL will not return success unless there is a 1273 * working, "ready" TDX module. Assume an absence of TDX 1274 * private pages until SEAMCALL is working. 1275 */ 1276 if (sret) 1277 return false; 1278 1279 /* 1280 * SEAMCALL was successful -- read page type (via RCX): 1281 * 1282 * - PT_NDA: Page is not used by the TDX module 1283 * - PT_RSVD: Reserved for Non-TDX use 1284 * - Others: Page is used by the TDX module 1285 * 1286 * Note PAMT pages are marked as PT_RSVD but they are also TDX 1287 * private memory. 1288 */ 1289 switch (args.rcx) { 1290 case PT_NDA: 1291 return false; 1292 case PT_RSVD: 1293 return is_pamt_page(phys); 1294 default: 1295 return true; 1296 } 1297 } 1298 1299 /* 1300 * Some TDX-capable CPUs have an erratum. A write to TDX private 1301 * memory poisons that memory, and a subsequent read of that memory 1302 * triggers #MC. 1303 * 1304 * Help distinguish erratum-triggered #MCs from a normal hardware one. 1305 * Just print additional message to show such #MC may be result of the 1306 * erratum. 1307 */ 1308 const char *tdx_dump_mce_info(struct mce *m) 1309 { 1310 if (!m || !mce_is_memory_error(m) || !mce_usable_address(m)) 1311 return NULL; 1312 1313 if (!paddr_is_tdx_private(m->addr)) 1314 return NULL; 1315 1316 return "TDX private memory error. Possible kernel bug."; 1317 } 1318 1319 static __init int record_keyid_partitioning(u32 *tdx_keyid_start, 1320 u32 *nr_tdx_keyids) 1321 { 1322 u32 _nr_mktme_keyids, _tdx_keyid_start, _nr_tdx_keyids; 1323 int ret; 1324 1325 /* 1326 * IA32_MKTME_KEYID_PARTIONING: 1327 * Bit [31:0]: Number of MKTME KeyIDs. 1328 * Bit [63:32]: Number of TDX private KeyIDs. 1329 */ 1330 ret = rdmsr_safe(MSR_IA32_MKTME_KEYID_PARTITIONING, &_nr_mktme_keyids, 1331 &_nr_tdx_keyids); 1332 if (ret || !_nr_tdx_keyids) 1333 return -EINVAL; 1334 1335 /* TDX KeyIDs start after the last MKTME KeyID. */ 1336 _tdx_keyid_start = _nr_mktme_keyids + 1; 1337 1338 *tdx_keyid_start = _tdx_keyid_start; 1339 *nr_tdx_keyids = _nr_tdx_keyids; 1340 1341 return 0; 1342 } 1343 1344 static bool is_tdx_memory(unsigned long start_pfn, unsigned long end_pfn) 1345 { 1346 struct tdx_memblock *tmb; 1347 1348 /* 1349 * This check assumes that the start_pfn<->end_pfn range does not 1350 * cross multiple @tdx_memlist entries. A single memory online 1351 * event across multiple memblocks (from which @tdx_memlist 1352 * entries are derived at the time of module initialization) is 1353 * not possible. This is because memory offline/online is done 1354 * on granularity of 'struct memory_block', and the hotpluggable 1355 * memory region (one memblock) must be multiple of memory_block. 1356 */ 1357 list_for_each_entry(tmb, &tdx_memlist, list) { 1358 if (start_pfn >= tmb->start_pfn && end_pfn <= tmb->end_pfn) 1359 return true; 1360 } 1361 return false; 1362 } 1363 1364 static int tdx_memory_notifier(struct notifier_block *nb, unsigned long action, 1365 void *v) 1366 { 1367 struct memory_notify *mn = v; 1368 1369 if (action != MEM_GOING_ONLINE) 1370 return NOTIFY_OK; 1371 1372 /* 1373 * Empty list means TDX isn't enabled. Allow any memory 1374 * to go online. 1375 */ 1376 if (list_empty(&tdx_memlist)) 1377 return NOTIFY_OK; 1378 1379 /* 1380 * The TDX memory configuration is static and can not be 1381 * changed. Reject onlining any memory which is outside of 1382 * the static configuration whether it supports TDX or not. 1383 */ 1384 if (is_tdx_memory(mn->start_pfn, mn->start_pfn + mn->nr_pages)) 1385 return NOTIFY_OK; 1386 1387 return NOTIFY_BAD; 1388 } 1389 1390 static struct notifier_block tdx_memory_nb = { 1391 .notifier_call = tdx_memory_notifier, 1392 }; 1393 1394 static void __init check_tdx_erratum(void) 1395 { 1396 /* 1397 * These CPUs have an erratum. A partial write from non-TD 1398 * software (e.g. via MOVNTI variants or UC/WC mapping) to TDX 1399 * private memory poisons that memory, and a subsequent read of 1400 * that memory triggers #MC. 1401 */ 1402 switch (boot_cpu_data.x86_vfm) { 1403 case INTEL_SAPPHIRERAPIDS_X: 1404 case INTEL_EMERALDRAPIDS_X: 1405 setup_force_cpu_bug(X86_BUG_TDX_PW_MCE); 1406 } 1407 } 1408 1409 void __init tdx_init(void) 1410 { 1411 u32 tdx_keyid_start, nr_tdx_keyids; 1412 int err; 1413 1414 err = record_keyid_partitioning(&tdx_keyid_start, &nr_tdx_keyids); 1415 if (err) 1416 return; 1417 1418 pr_info("BIOS enabled: private KeyID range [%u, %u)\n", 1419 tdx_keyid_start, tdx_keyid_start + nr_tdx_keyids); 1420 1421 /* 1422 * The TDX module itself requires one 'global KeyID' to protect 1423 * its metadata. If there's only one TDX KeyID, there won't be 1424 * any left for TDX guests thus there's no point to enable TDX 1425 * at all. 1426 */ 1427 if (nr_tdx_keyids < 2) { 1428 pr_err("initialization failed: too few private KeyIDs available.\n"); 1429 return; 1430 } 1431 1432 /* 1433 * At this point, hibernation_available() indicates whether or 1434 * not hibernation support has been permanently disabled. 1435 */ 1436 if (hibernation_available()) { 1437 pr_err("initialization failed: Hibernation support is enabled\n"); 1438 return; 1439 } 1440 1441 err = register_memory_notifier(&tdx_memory_nb); 1442 if (err) { 1443 pr_err("initialization failed: register_memory_notifier() failed (%d)\n", 1444 err); 1445 return; 1446 } 1447 1448 #if defined(CONFIG_ACPI) && defined(CONFIG_SUSPEND) 1449 pr_info("Disable ACPI S3. Turn off TDX in the BIOS to use ACPI S3.\n"); 1450 acpi_suspend_lowlevel = NULL; 1451 #endif 1452 1453 /* 1454 * Just use the first TDX KeyID as the 'global KeyID' and 1455 * leave the rest for TDX guests. 1456 */ 1457 tdx_global_keyid = tdx_keyid_start; 1458 tdx_guest_keyid_start = tdx_keyid_start + 1; 1459 tdx_nr_guest_keyids = nr_tdx_keyids - 1; 1460 1461 setup_force_cpu_cap(X86_FEATURE_TDX_HOST_PLATFORM); 1462 1463 check_tdx_erratum(); 1464 } 1465 1466 const struct tdx_sys_info *tdx_get_sysinfo(void) 1467 { 1468 const struct tdx_sys_info *p = NULL; 1469 1470 /* Make sure all fields in @tdx_sysinfo have been populated */ 1471 mutex_lock(&tdx_module_lock); 1472 if (tdx_module_status == TDX_MODULE_INITIALIZED) 1473 p = (const struct tdx_sys_info *)&tdx_sysinfo; 1474 mutex_unlock(&tdx_module_lock); 1475 1476 return p; 1477 } 1478 EXPORT_SYMBOL_GPL(tdx_get_sysinfo); 1479 1480 u32 tdx_get_nr_guest_keyids(void) 1481 { 1482 return tdx_nr_guest_keyids; 1483 } 1484 EXPORT_SYMBOL_GPL(tdx_get_nr_guest_keyids); 1485 1486 int tdx_guest_keyid_alloc(void) 1487 { 1488 return ida_alloc_range(&tdx_guest_keyid_pool, tdx_guest_keyid_start, 1489 tdx_guest_keyid_start + tdx_nr_guest_keyids - 1, 1490 GFP_KERNEL); 1491 } 1492 EXPORT_SYMBOL_GPL(tdx_guest_keyid_alloc); 1493 1494 void tdx_guest_keyid_free(unsigned int keyid) 1495 { 1496 ida_free(&tdx_guest_keyid_pool, keyid); 1497 } 1498 EXPORT_SYMBOL_GPL(tdx_guest_keyid_free); 1499 1500 static inline u64 tdx_tdr_pa(struct tdx_td *td) 1501 { 1502 return page_to_phys(td->tdr_page); 1503 } 1504 1505 static inline u64 tdx_tdvpr_pa(struct tdx_vp *td) 1506 { 1507 return page_to_phys(td->tdvpr_page); 1508 } 1509 1510 /* 1511 * The TDX module exposes a CLFLUSH_BEFORE_ALLOC bit to specify whether 1512 * a CLFLUSH of pages is required before handing them to the TDX module. 1513 * Be conservative and make the code simpler by doing the CLFLUSH 1514 * unconditionally. 1515 */ 1516 static void tdx_clflush_page(struct page *page) 1517 { 1518 clflush_cache_range(page_to_virt(page), PAGE_SIZE); 1519 } 1520 1521 noinstr __flatten u64 tdh_vp_enter(struct tdx_vp *td, struct tdx_module_args *args) 1522 { 1523 args->rcx = tdx_tdvpr_pa(td); 1524 1525 return __seamcall_saved_ret(TDH_VP_ENTER, args); 1526 } 1527 EXPORT_SYMBOL_GPL(tdh_vp_enter); 1528 1529 u64 tdh_mng_addcx(struct tdx_td *td, struct page *tdcs_page) 1530 { 1531 struct tdx_module_args args = { 1532 .rcx = page_to_phys(tdcs_page), 1533 .rdx = tdx_tdr_pa(td), 1534 }; 1535 1536 tdx_clflush_page(tdcs_page); 1537 return seamcall(TDH_MNG_ADDCX, &args); 1538 } 1539 EXPORT_SYMBOL_GPL(tdh_mng_addcx); 1540 1541 u64 tdh_mem_page_add(struct tdx_td *td, u64 gpa, struct page *page, struct page *source, u64 *ext_err1, u64 *ext_err2) 1542 { 1543 struct tdx_module_args args = { 1544 .rcx = gpa, 1545 .rdx = tdx_tdr_pa(td), 1546 .r8 = page_to_phys(page), 1547 .r9 = page_to_phys(source), 1548 }; 1549 u64 ret; 1550 1551 tdx_clflush_page(page); 1552 ret = seamcall_ret(TDH_MEM_PAGE_ADD, &args); 1553 1554 *ext_err1 = args.rcx; 1555 *ext_err2 = args.rdx; 1556 1557 return ret; 1558 } 1559 EXPORT_SYMBOL_GPL(tdh_mem_page_add); 1560 1561 u64 tdh_mem_sept_add(struct tdx_td *td, u64 gpa, int level, struct page *page, u64 *ext_err1, u64 *ext_err2) 1562 { 1563 struct tdx_module_args args = { 1564 .rcx = gpa | level, 1565 .rdx = tdx_tdr_pa(td), 1566 .r8 = page_to_phys(page), 1567 }; 1568 u64 ret; 1569 1570 tdx_clflush_page(page); 1571 ret = seamcall_ret(TDH_MEM_SEPT_ADD, &args); 1572 1573 *ext_err1 = args.rcx; 1574 *ext_err2 = args.rdx; 1575 1576 return ret; 1577 } 1578 EXPORT_SYMBOL_GPL(tdh_mem_sept_add); 1579 1580 u64 tdh_vp_addcx(struct tdx_vp *vp, struct page *tdcx_page) 1581 { 1582 struct tdx_module_args args = { 1583 .rcx = page_to_phys(tdcx_page), 1584 .rdx = tdx_tdvpr_pa(vp), 1585 }; 1586 1587 tdx_clflush_page(tdcx_page); 1588 return seamcall(TDH_VP_ADDCX, &args); 1589 } 1590 EXPORT_SYMBOL_GPL(tdh_vp_addcx); 1591 1592 u64 tdh_mem_page_aug(struct tdx_td *td, u64 gpa, int level, struct page *page, u64 *ext_err1, u64 *ext_err2) 1593 { 1594 struct tdx_module_args args = { 1595 .rcx = gpa | level, 1596 .rdx = tdx_tdr_pa(td), 1597 .r8 = page_to_phys(page), 1598 }; 1599 u64 ret; 1600 1601 tdx_clflush_page(page); 1602 ret = seamcall_ret(TDH_MEM_PAGE_AUG, &args); 1603 1604 *ext_err1 = args.rcx; 1605 *ext_err2 = args.rdx; 1606 1607 return ret; 1608 } 1609 EXPORT_SYMBOL_GPL(tdh_mem_page_aug); 1610 1611 u64 tdh_mem_range_block(struct tdx_td *td, u64 gpa, int level, u64 *ext_err1, u64 *ext_err2) 1612 { 1613 struct tdx_module_args args = { 1614 .rcx = gpa | level, 1615 .rdx = tdx_tdr_pa(td), 1616 }; 1617 u64 ret; 1618 1619 ret = seamcall_ret(TDH_MEM_RANGE_BLOCK, &args); 1620 1621 *ext_err1 = args.rcx; 1622 *ext_err2 = args.rdx; 1623 1624 return ret; 1625 } 1626 EXPORT_SYMBOL_GPL(tdh_mem_range_block); 1627 1628 u64 tdh_mng_key_config(struct tdx_td *td) 1629 { 1630 struct tdx_module_args args = { 1631 .rcx = tdx_tdr_pa(td), 1632 }; 1633 1634 return seamcall(TDH_MNG_KEY_CONFIG, &args); 1635 } 1636 EXPORT_SYMBOL_GPL(tdh_mng_key_config); 1637 1638 u64 tdh_mng_create(struct tdx_td *td, u16 hkid) 1639 { 1640 struct tdx_module_args args = { 1641 .rcx = tdx_tdr_pa(td), 1642 .rdx = hkid, 1643 }; 1644 1645 tdx_clflush_page(td->tdr_page); 1646 return seamcall(TDH_MNG_CREATE, &args); 1647 } 1648 EXPORT_SYMBOL_GPL(tdh_mng_create); 1649 1650 u64 tdh_vp_create(struct tdx_td *td, struct tdx_vp *vp) 1651 { 1652 struct tdx_module_args args = { 1653 .rcx = tdx_tdvpr_pa(vp), 1654 .rdx = tdx_tdr_pa(td), 1655 }; 1656 1657 tdx_clflush_page(vp->tdvpr_page); 1658 return seamcall(TDH_VP_CREATE, &args); 1659 } 1660 EXPORT_SYMBOL_GPL(tdh_vp_create); 1661 1662 u64 tdh_mng_rd(struct tdx_td *td, u64 field, u64 *data) 1663 { 1664 struct tdx_module_args args = { 1665 .rcx = tdx_tdr_pa(td), 1666 .rdx = field, 1667 }; 1668 u64 ret; 1669 1670 ret = seamcall_ret(TDH_MNG_RD, &args); 1671 1672 /* R8: Content of the field, or 0 in case of error. */ 1673 *data = args.r8; 1674 1675 return ret; 1676 } 1677 EXPORT_SYMBOL_GPL(tdh_mng_rd); 1678 1679 u64 tdh_mr_extend(struct tdx_td *td, u64 gpa, u64 *ext_err1, u64 *ext_err2) 1680 { 1681 struct tdx_module_args args = { 1682 .rcx = gpa, 1683 .rdx = tdx_tdr_pa(td), 1684 }; 1685 u64 ret; 1686 1687 ret = seamcall_ret(TDH_MR_EXTEND, &args); 1688 1689 *ext_err1 = args.rcx; 1690 *ext_err2 = args.rdx; 1691 1692 return ret; 1693 } 1694 EXPORT_SYMBOL_GPL(tdh_mr_extend); 1695 1696 u64 tdh_mr_finalize(struct tdx_td *td) 1697 { 1698 struct tdx_module_args args = { 1699 .rcx = tdx_tdr_pa(td), 1700 }; 1701 1702 return seamcall(TDH_MR_FINALIZE, &args); 1703 } 1704 EXPORT_SYMBOL_GPL(tdh_mr_finalize); 1705 1706 u64 tdh_vp_flush(struct tdx_vp *vp) 1707 { 1708 struct tdx_module_args args = { 1709 .rcx = tdx_tdvpr_pa(vp), 1710 }; 1711 1712 return seamcall(TDH_VP_FLUSH, &args); 1713 } 1714 EXPORT_SYMBOL_GPL(tdh_vp_flush); 1715 1716 u64 tdh_mng_vpflushdone(struct tdx_td *td) 1717 { 1718 struct tdx_module_args args = { 1719 .rcx = tdx_tdr_pa(td), 1720 }; 1721 1722 return seamcall(TDH_MNG_VPFLUSHDONE, &args); 1723 } 1724 EXPORT_SYMBOL_GPL(tdh_mng_vpflushdone); 1725 1726 u64 tdh_mng_key_freeid(struct tdx_td *td) 1727 { 1728 struct tdx_module_args args = { 1729 .rcx = tdx_tdr_pa(td), 1730 }; 1731 1732 return seamcall(TDH_MNG_KEY_FREEID, &args); 1733 } 1734 EXPORT_SYMBOL_GPL(tdh_mng_key_freeid); 1735 1736 u64 tdh_mng_init(struct tdx_td *td, u64 td_params, u64 *extended_err) 1737 { 1738 struct tdx_module_args args = { 1739 .rcx = tdx_tdr_pa(td), 1740 .rdx = td_params, 1741 }; 1742 u64 ret; 1743 1744 ret = seamcall_ret(TDH_MNG_INIT, &args); 1745 1746 *extended_err = args.rcx; 1747 1748 return ret; 1749 } 1750 EXPORT_SYMBOL_GPL(tdh_mng_init); 1751 1752 u64 tdh_vp_rd(struct tdx_vp *vp, u64 field, u64 *data) 1753 { 1754 struct tdx_module_args args = { 1755 .rcx = tdx_tdvpr_pa(vp), 1756 .rdx = field, 1757 }; 1758 u64 ret; 1759 1760 ret = seamcall_ret(TDH_VP_RD, &args); 1761 1762 /* R8: Content of the field, or 0 in case of error. */ 1763 *data = args.r8; 1764 1765 return ret; 1766 } 1767 EXPORT_SYMBOL_GPL(tdh_vp_rd); 1768 1769 u64 tdh_vp_wr(struct tdx_vp *vp, u64 field, u64 data, u64 mask) 1770 { 1771 struct tdx_module_args args = { 1772 .rcx = tdx_tdvpr_pa(vp), 1773 .rdx = field, 1774 .r8 = data, 1775 .r9 = mask, 1776 }; 1777 1778 return seamcall(TDH_VP_WR, &args); 1779 } 1780 EXPORT_SYMBOL_GPL(tdh_vp_wr); 1781 1782 u64 tdh_vp_init(struct tdx_vp *vp, u64 initial_rcx, u32 x2apicid) 1783 { 1784 struct tdx_module_args args = { 1785 .rcx = tdx_tdvpr_pa(vp), 1786 .rdx = initial_rcx, 1787 .r8 = x2apicid, 1788 }; 1789 1790 /* apicid requires version == 1. */ 1791 return seamcall(TDH_VP_INIT | (1ULL << TDX_VERSION_SHIFT), &args); 1792 } 1793 EXPORT_SYMBOL_GPL(tdh_vp_init); 1794 1795 /* 1796 * TDX ABI defines output operands as PT, OWNER and SIZE. These are TDX defined fomats. 1797 * So despite the names, they must be interpted specially as described by the spec. Return 1798 * them only for error reporting purposes. 1799 */ 1800 u64 tdh_phymem_page_reclaim(struct page *page, u64 *tdx_pt, u64 *tdx_owner, u64 *tdx_size) 1801 { 1802 struct tdx_module_args args = { 1803 .rcx = page_to_phys(page), 1804 }; 1805 u64 ret; 1806 1807 ret = seamcall_ret(TDH_PHYMEM_PAGE_RECLAIM, &args); 1808 1809 *tdx_pt = args.rcx; 1810 *tdx_owner = args.rdx; 1811 *tdx_size = args.r8; 1812 1813 return ret; 1814 } 1815 EXPORT_SYMBOL_GPL(tdh_phymem_page_reclaim); 1816 1817 u64 tdh_mem_track(struct tdx_td *td) 1818 { 1819 struct tdx_module_args args = { 1820 .rcx = tdx_tdr_pa(td), 1821 }; 1822 1823 return seamcall(TDH_MEM_TRACK, &args); 1824 } 1825 EXPORT_SYMBOL_GPL(tdh_mem_track); 1826 1827 u64 tdh_mem_page_remove(struct tdx_td *td, u64 gpa, u64 level, u64 *ext_err1, u64 *ext_err2) 1828 { 1829 struct tdx_module_args args = { 1830 .rcx = gpa | level, 1831 .rdx = tdx_tdr_pa(td), 1832 }; 1833 u64 ret; 1834 1835 ret = seamcall_ret(TDH_MEM_PAGE_REMOVE, &args); 1836 1837 *ext_err1 = args.rcx; 1838 *ext_err2 = args.rdx; 1839 1840 return ret; 1841 } 1842 EXPORT_SYMBOL_GPL(tdh_mem_page_remove); 1843 1844 u64 tdh_phymem_cache_wb(bool resume) 1845 { 1846 struct tdx_module_args args = { 1847 .rcx = resume ? 1 : 0, 1848 }; 1849 1850 return seamcall(TDH_PHYMEM_CACHE_WB, &args); 1851 } 1852 EXPORT_SYMBOL_GPL(tdh_phymem_cache_wb); 1853 1854 u64 tdh_phymem_page_wbinvd_tdr(struct tdx_td *td) 1855 { 1856 struct tdx_module_args args = {}; 1857 1858 args.rcx = mk_keyed_paddr(tdx_global_keyid, td->tdr_page); 1859 1860 return seamcall(TDH_PHYMEM_PAGE_WBINVD, &args); 1861 } 1862 EXPORT_SYMBOL_GPL(tdh_phymem_page_wbinvd_tdr); 1863 1864 u64 tdh_phymem_page_wbinvd_hkid(u64 hkid, struct page *page) 1865 { 1866 struct tdx_module_args args = {}; 1867 1868 args.rcx = mk_keyed_paddr(hkid, page); 1869 1870 return seamcall(TDH_PHYMEM_PAGE_WBINVD, &args); 1871 } 1872 EXPORT_SYMBOL_GPL(tdh_phymem_page_wbinvd_hkid); 1873