1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Core of Xen paravirt_ops implementation. 4 * 5 * This file contains the xen_paravirt_ops structure itself, and the 6 * implementations for: 7 * - privileged instructions 8 * - interrupt flags 9 * - segment operations 10 * - booting and setup 11 * 12 * Jeremy Fitzhardinge <jeremy@xensource.com>, XenSource Inc, 2007 13 */ 14 15 #include <linux/cpu.h> 16 #include <linux/kernel.h> 17 #include <linux/init.h> 18 #include <linux/smp.h> 19 #include <linux/preempt.h> 20 #include <linux/hardirq.h> 21 #include <linux/percpu.h> 22 #include <linux/delay.h> 23 #include <linux/start_kernel.h> 24 #include <linux/sched.h> 25 #include <linux/kprobes.h> 26 #include <linux/memblock.h> 27 #include <linux/export.h> 28 #include <linux/mm.h> 29 #include <linux/page-flags.h> 30 #include <linux/highmem.h> 31 #include <linux/console.h> 32 #include <linux/pci.h> 33 #include <linux/gfp.h> 34 #include <linux/edd.h> 35 #include <linux/frame.h> 36 37 #include <xen/xen.h> 38 #include <xen/events.h> 39 #include <xen/interface/xen.h> 40 #include <xen/interface/version.h> 41 #include <xen/interface/physdev.h> 42 #include <xen/interface/vcpu.h> 43 #include <xen/interface/memory.h> 44 #include <xen/interface/nmi.h> 45 #include <xen/interface/xen-mca.h> 46 #include <xen/features.h> 47 #include <xen/page.h> 48 #include <xen/hvc-console.h> 49 #include <xen/acpi.h> 50 51 #include <asm/paravirt.h> 52 #include <asm/apic.h> 53 #include <asm/page.h> 54 #include <asm/xen/pci.h> 55 #include <asm/xen/hypercall.h> 56 #include <asm/xen/hypervisor.h> 57 #include <asm/xen/cpuid.h> 58 #include <asm/fixmap.h> 59 #include <asm/processor.h> 60 #include <asm/proto.h> 61 #include <asm/msr-index.h> 62 #include <asm/traps.h> 63 #include <asm/setup.h> 64 #include <asm/desc.h> 65 #include <asm/pgalloc.h> 66 #include <asm/tlbflush.h> 67 #include <asm/reboot.h> 68 #include <asm/stackprotector.h> 69 #include <asm/hypervisor.h> 70 #include <asm/mach_traps.h> 71 #include <asm/mwait.h> 72 #include <asm/pci_x86.h> 73 #include <asm/cpu.h> 74 #ifdef CONFIG_X86_IOPL_IOPERM 75 #include <asm/io_bitmap.h> 76 #endif 77 78 #ifdef CONFIG_ACPI 79 #include <linux/acpi.h> 80 #include <asm/acpi.h> 81 #include <acpi/pdc_intel.h> 82 #include <acpi/processor.h> 83 #include <xen/interface/platform.h> 84 #endif 85 86 #include "xen-ops.h" 87 #include "mmu.h" 88 #include "smp.h" 89 #include "multicalls.h" 90 #include "pmu.h" 91 92 #include "../kernel/cpu/cpu.h" /* get_cpu_cap() */ 93 94 void *xen_initial_gdt; 95 96 static int xen_cpu_up_prepare_pv(unsigned int cpu); 97 static int xen_cpu_dead_pv(unsigned int cpu); 98 99 struct tls_descs { 100 struct desc_struct desc[3]; 101 }; 102 103 /* 104 * Updating the 3 TLS descriptors in the GDT on every task switch is 105 * surprisingly expensive so we avoid updating them if they haven't 106 * changed. Since Xen writes different descriptors than the one 107 * passed in the update_descriptor hypercall we keep shadow copies to 108 * compare against. 109 */ 110 static DEFINE_PER_CPU(struct tls_descs, shadow_tls_desc); 111 112 static void __init xen_banner(void) 113 { 114 unsigned version = HYPERVISOR_xen_version(XENVER_version, NULL); 115 struct xen_extraversion extra; 116 HYPERVISOR_xen_version(XENVER_extraversion, &extra); 117 118 pr_info("Booting paravirtualized kernel on %s\n", pv_info.name); 119 printk(KERN_INFO "Xen version: %d.%d%s%s\n", 120 version >> 16, version & 0xffff, extra.extraversion, 121 xen_feature(XENFEAT_mmu_pt_update_preserve_ad) ? " (preserve-AD)" : ""); 122 123 #ifdef CONFIG_X86_32 124 pr_warn("WARNING! WARNING! WARNING! WARNING! WARNING! WARNING! WARNING!\n" 125 "Support for running as 32-bit PV-guest under Xen will soon be removed\n" 126 "from the Linux kernel!\n" 127 "Please use either a 64-bit kernel or switch to HVM or PVH mode!\n" 128 "WARNING! WARNING! WARNING! WARNING! WARNING! WARNING! WARNING!\n"); 129 #endif 130 } 131 132 static void __init xen_pv_init_platform(void) 133 { 134 populate_extra_pte(fix_to_virt(FIX_PARAVIRT_BOOTMAP)); 135 136 set_fixmap(FIX_PARAVIRT_BOOTMAP, xen_start_info->shared_info); 137 HYPERVISOR_shared_info = (void *)fix_to_virt(FIX_PARAVIRT_BOOTMAP); 138 139 /* xen clock uses per-cpu vcpu_info, need to init it for boot cpu */ 140 xen_vcpu_info_reset(0); 141 142 /* pvclock is in shared info area */ 143 xen_init_time_ops(); 144 } 145 146 static void __init xen_pv_guest_late_init(void) 147 { 148 #ifndef CONFIG_SMP 149 /* Setup shared vcpu info for non-smp configurations */ 150 xen_setup_vcpu_info_placement(); 151 #endif 152 } 153 154 /* Check if running on Xen version (major, minor) or later */ 155 bool 156 xen_running_on_version_or_later(unsigned int major, unsigned int minor) 157 { 158 unsigned int version; 159 160 if (!xen_domain()) 161 return false; 162 163 version = HYPERVISOR_xen_version(XENVER_version, NULL); 164 if ((((version >> 16) == major) && ((version & 0xffff) >= minor)) || 165 ((version >> 16) > major)) 166 return true; 167 return false; 168 } 169 170 static __read_mostly unsigned int cpuid_leaf5_ecx_val; 171 static __read_mostly unsigned int cpuid_leaf5_edx_val; 172 173 static void xen_cpuid(unsigned int *ax, unsigned int *bx, 174 unsigned int *cx, unsigned int *dx) 175 { 176 unsigned maskebx = ~0; 177 178 /* 179 * Mask out inconvenient features, to try and disable as many 180 * unsupported kernel subsystems as possible. 181 */ 182 switch (*ax) { 183 case CPUID_MWAIT_LEAF: 184 /* Synthesize the values.. */ 185 *ax = 0; 186 *bx = 0; 187 *cx = cpuid_leaf5_ecx_val; 188 *dx = cpuid_leaf5_edx_val; 189 return; 190 191 case 0xb: 192 /* Suppress extended topology stuff */ 193 maskebx = 0; 194 break; 195 } 196 197 asm(XEN_EMULATE_PREFIX "cpuid" 198 : "=a" (*ax), 199 "=b" (*bx), 200 "=c" (*cx), 201 "=d" (*dx) 202 : "0" (*ax), "2" (*cx)); 203 204 *bx &= maskebx; 205 } 206 STACK_FRAME_NON_STANDARD(xen_cpuid); /* XEN_EMULATE_PREFIX */ 207 208 static bool __init xen_check_mwait(void) 209 { 210 #ifdef CONFIG_ACPI 211 struct xen_platform_op op = { 212 .cmd = XENPF_set_processor_pminfo, 213 .u.set_pminfo.id = -1, 214 .u.set_pminfo.type = XEN_PM_PDC, 215 }; 216 uint32_t buf[3]; 217 unsigned int ax, bx, cx, dx; 218 unsigned int mwait_mask; 219 220 /* We need to determine whether it is OK to expose the MWAIT 221 * capability to the kernel to harvest deeper than C3 states from ACPI 222 * _CST using the processor_harvest_xen.c module. For this to work, we 223 * need to gather the MWAIT_LEAF values (which the cstate.c code 224 * checks against). The hypervisor won't expose the MWAIT flag because 225 * it would break backwards compatibility; so we will find out directly 226 * from the hardware and hypercall. 227 */ 228 if (!xen_initial_domain()) 229 return false; 230 231 /* 232 * When running under platform earlier than Xen4.2, do not expose 233 * mwait, to avoid the risk of loading native acpi pad driver 234 */ 235 if (!xen_running_on_version_or_later(4, 2)) 236 return false; 237 238 ax = 1; 239 cx = 0; 240 241 native_cpuid(&ax, &bx, &cx, &dx); 242 243 mwait_mask = (1 << (X86_FEATURE_EST % 32)) | 244 (1 << (X86_FEATURE_MWAIT % 32)); 245 246 if ((cx & mwait_mask) != mwait_mask) 247 return false; 248 249 /* We need to emulate the MWAIT_LEAF and for that we need both 250 * ecx and edx. The hypercall provides only partial information. 251 */ 252 253 ax = CPUID_MWAIT_LEAF; 254 bx = 0; 255 cx = 0; 256 dx = 0; 257 258 native_cpuid(&ax, &bx, &cx, &dx); 259 260 /* Ask the Hypervisor whether to clear ACPI_PDC_C_C2C3_FFH. If so, 261 * don't expose MWAIT_LEAF and let ACPI pick the IOPORT version of C3. 262 */ 263 buf[0] = ACPI_PDC_REVISION_ID; 264 buf[1] = 1; 265 buf[2] = (ACPI_PDC_C_CAPABILITY_SMP | ACPI_PDC_EST_CAPABILITY_SWSMP); 266 267 set_xen_guest_handle(op.u.set_pminfo.pdc, buf); 268 269 if ((HYPERVISOR_platform_op(&op) == 0) && 270 (buf[2] & (ACPI_PDC_C_C1_FFH | ACPI_PDC_C_C2C3_FFH))) { 271 cpuid_leaf5_ecx_val = cx; 272 cpuid_leaf5_edx_val = dx; 273 } 274 return true; 275 #else 276 return false; 277 #endif 278 } 279 280 static bool __init xen_check_xsave(void) 281 { 282 unsigned int cx, xsave_mask; 283 284 cx = cpuid_ecx(1); 285 286 xsave_mask = (1 << (X86_FEATURE_XSAVE % 32)) | 287 (1 << (X86_FEATURE_OSXSAVE % 32)); 288 289 /* Xen will set CR4.OSXSAVE if supported and not disabled by force */ 290 return (cx & xsave_mask) == xsave_mask; 291 } 292 293 static void __init xen_init_capabilities(void) 294 { 295 setup_force_cpu_cap(X86_FEATURE_XENPV); 296 setup_clear_cpu_cap(X86_FEATURE_DCA); 297 setup_clear_cpu_cap(X86_FEATURE_APERFMPERF); 298 setup_clear_cpu_cap(X86_FEATURE_MTRR); 299 setup_clear_cpu_cap(X86_FEATURE_ACC); 300 setup_clear_cpu_cap(X86_FEATURE_X2APIC); 301 setup_clear_cpu_cap(X86_FEATURE_SME); 302 303 /* 304 * Xen PV would need some work to support PCID: CR3 handling as well 305 * as xen_flush_tlb_others() would need updating. 306 */ 307 setup_clear_cpu_cap(X86_FEATURE_PCID); 308 309 if (!xen_initial_domain()) 310 setup_clear_cpu_cap(X86_FEATURE_ACPI); 311 312 if (xen_check_mwait()) 313 setup_force_cpu_cap(X86_FEATURE_MWAIT); 314 else 315 setup_clear_cpu_cap(X86_FEATURE_MWAIT); 316 317 if (!xen_check_xsave()) { 318 setup_clear_cpu_cap(X86_FEATURE_XSAVE); 319 setup_clear_cpu_cap(X86_FEATURE_OSXSAVE); 320 } 321 } 322 323 static void xen_set_debugreg(int reg, unsigned long val) 324 { 325 HYPERVISOR_set_debugreg(reg, val); 326 } 327 328 static unsigned long xen_get_debugreg(int reg) 329 { 330 return HYPERVISOR_get_debugreg(reg); 331 } 332 333 static void xen_end_context_switch(struct task_struct *next) 334 { 335 xen_mc_flush(); 336 paravirt_end_context_switch(next); 337 } 338 339 static unsigned long xen_store_tr(void) 340 { 341 return 0; 342 } 343 344 /* 345 * Set the page permissions for a particular virtual address. If the 346 * address is a vmalloc mapping (or other non-linear mapping), then 347 * find the linear mapping of the page and also set its protections to 348 * match. 349 */ 350 static void set_aliased_prot(void *v, pgprot_t prot) 351 { 352 int level; 353 pte_t *ptep; 354 pte_t pte; 355 unsigned long pfn; 356 struct page *page; 357 unsigned char dummy; 358 359 ptep = lookup_address((unsigned long)v, &level); 360 BUG_ON(ptep == NULL); 361 362 pfn = pte_pfn(*ptep); 363 page = pfn_to_page(pfn); 364 365 pte = pfn_pte(pfn, prot); 366 367 /* 368 * Careful: update_va_mapping() will fail if the virtual address 369 * we're poking isn't populated in the page tables. We don't 370 * need to worry about the direct map (that's always in the page 371 * tables), but we need to be careful about vmap space. In 372 * particular, the top level page table can lazily propagate 373 * entries between processes, so if we've switched mms since we 374 * vmapped the target in the first place, we might not have the 375 * top-level page table entry populated. 376 * 377 * We disable preemption because we want the same mm active when 378 * we probe the target and when we issue the hypercall. We'll 379 * have the same nominal mm, but if we're a kernel thread, lazy 380 * mm dropping could change our pgd. 381 * 382 * Out of an abundance of caution, this uses __get_user() to fault 383 * in the target address just in case there's some obscure case 384 * in which the target address isn't readable. 385 */ 386 387 preempt_disable(); 388 389 copy_from_kernel_nofault(&dummy, v, 1); 390 391 if (HYPERVISOR_update_va_mapping((unsigned long)v, pte, 0)) 392 BUG(); 393 394 if (!PageHighMem(page)) { 395 void *av = __va(PFN_PHYS(pfn)); 396 397 if (av != v) 398 if (HYPERVISOR_update_va_mapping((unsigned long)av, pte, 0)) 399 BUG(); 400 } else 401 kmap_flush_unused(); 402 403 preempt_enable(); 404 } 405 406 static void xen_alloc_ldt(struct desc_struct *ldt, unsigned entries) 407 { 408 const unsigned entries_per_page = PAGE_SIZE / LDT_ENTRY_SIZE; 409 int i; 410 411 /* 412 * We need to mark the all aliases of the LDT pages RO. We 413 * don't need to call vm_flush_aliases(), though, since that's 414 * only responsible for flushing aliases out the TLBs, not the 415 * page tables, and Xen will flush the TLB for us if needed. 416 * 417 * To avoid confusing future readers: none of this is necessary 418 * to load the LDT. The hypervisor only checks this when the 419 * LDT is faulted in due to subsequent descriptor access. 420 */ 421 422 for (i = 0; i < entries; i += entries_per_page) 423 set_aliased_prot(ldt + i, PAGE_KERNEL_RO); 424 } 425 426 static void xen_free_ldt(struct desc_struct *ldt, unsigned entries) 427 { 428 const unsigned entries_per_page = PAGE_SIZE / LDT_ENTRY_SIZE; 429 int i; 430 431 for (i = 0; i < entries; i += entries_per_page) 432 set_aliased_prot(ldt + i, PAGE_KERNEL); 433 } 434 435 static void xen_set_ldt(const void *addr, unsigned entries) 436 { 437 struct mmuext_op *op; 438 struct multicall_space mcs = xen_mc_entry(sizeof(*op)); 439 440 trace_xen_cpu_set_ldt(addr, entries); 441 442 op = mcs.args; 443 op->cmd = MMUEXT_SET_LDT; 444 op->arg1.linear_addr = (unsigned long)addr; 445 op->arg2.nr_ents = entries; 446 447 MULTI_mmuext_op(mcs.mc, op, 1, NULL, DOMID_SELF); 448 449 xen_mc_issue(PARAVIRT_LAZY_CPU); 450 } 451 452 static void xen_load_gdt(const struct desc_ptr *dtr) 453 { 454 unsigned long va = dtr->address; 455 unsigned int size = dtr->size + 1; 456 unsigned long pfn, mfn; 457 int level; 458 pte_t *ptep; 459 void *virt; 460 461 /* @size should be at most GDT_SIZE which is smaller than PAGE_SIZE. */ 462 BUG_ON(size > PAGE_SIZE); 463 BUG_ON(va & ~PAGE_MASK); 464 465 /* 466 * The GDT is per-cpu and is in the percpu data area. 467 * That can be virtually mapped, so we need to do a 468 * page-walk to get the underlying MFN for the 469 * hypercall. The page can also be in the kernel's 470 * linear range, so we need to RO that mapping too. 471 */ 472 ptep = lookup_address(va, &level); 473 BUG_ON(ptep == NULL); 474 475 pfn = pte_pfn(*ptep); 476 mfn = pfn_to_mfn(pfn); 477 virt = __va(PFN_PHYS(pfn)); 478 479 make_lowmem_page_readonly((void *)va); 480 make_lowmem_page_readonly(virt); 481 482 if (HYPERVISOR_set_gdt(&mfn, size / sizeof(struct desc_struct))) 483 BUG(); 484 } 485 486 /* 487 * load_gdt for early boot, when the gdt is only mapped once 488 */ 489 static void __init xen_load_gdt_boot(const struct desc_ptr *dtr) 490 { 491 unsigned long va = dtr->address; 492 unsigned int size = dtr->size + 1; 493 unsigned long pfn, mfn; 494 pte_t pte; 495 496 /* @size should be at most GDT_SIZE which is smaller than PAGE_SIZE. */ 497 BUG_ON(size > PAGE_SIZE); 498 BUG_ON(va & ~PAGE_MASK); 499 500 pfn = virt_to_pfn(va); 501 mfn = pfn_to_mfn(pfn); 502 503 pte = pfn_pte(pfn, PAGE_KERNEL_RO); 504 505 if (HYPERVISOR_update_va_mapping((unsigned long)va, pte, 0)) 506 BUG(); 507 508 if (HYPERVISOR_set_gdt(&mfn, size / sizeof(struct desc_struct))) 509 BUG(); 510 } 511 512 static inline bool desc_equal(const struct desc_struct *d1, 513 const struct desc_struct *d2) 514 { 515 return !memcmp(d1, d2, sizeof(*d1)); 516 } 517 518 static void load_TLS_descriptor(struct thread_struct *t, 519 unsigned int cpu, unsigned int i) 520 { 521 struct desc_struct *shadow = &per_cpu(shadow_tls_desc, cpu).desc[i]; 522 struct desc_struct *gdt; 523 xmaddr_t maddr; 524 struct multicall_space mc; 525 526 if (desc_equal(shadow, &t->tls_array[i])) 527 return; 528 529 *shadow = t->tls_array[i]; 530 531 gdt = get_cpu_gdt_rw(cpu); 532 maddr = arbitrary_virt_to_machine(&gdt[GDT_ENTRY_TLS_MIN+i]); 533 mc = __xen_mc_entry(0); 534 535 MULTI_update_descriptor(mc.mc, maddr.maddr, t->tls_array[i]); 536 } 537 538 static void xen_load_tls(struct thread_struct *t, unsigned int cpu) 539 { 540 /* 541 * XXX sleazy hack: If we're being called in a lazy-cpu zone 542 * and lazy gs handling is enabled, it means we're in a 543 * context switch, and %gs has just been saved. This means we 544 * can zero it out to prevent faults on exit from the 545 * hypervisor if the next process has no %gs. Either way, it 546 * has been saved, and the new value will get loaded properly. 547 * This will go away as soon as Xen has been modified to not 548 * save/restore %gs for normal hypercalls. 549 * 550 * On x86_64, this hack is not used for %gs, because gs points 551 * to KERNEL_GS_BASE (and uses it for PDA references), so we 552 * must not zero %gs on x86_64 553 * 554 * For x86_64, we need to zero %fs, otherwise we may get an 555 * exception between the new %fs descriptor being loaded and 556 * %fs being effectively cleared at __switch_to(). 557 */ 558 if (paravirt_get_lazy_mode() == PARAVIRT_LAZY_CPU) { 559 #ifdef CONFIG_X86_32 560 lazy_load_gs(0); 561 #else 562 loadsegment(fs, 0); 563 #endif 564 } 565 566 xen_mc_batch(); 567 568 load_TLS_descriptor(t, cpu, 0); 569 load_TLS_descriptor(t, cpu, 1); 570 load_TLS_descriptor(t, cpu, 2); 571 572 xen_mc_issue(PARAVIRT_LAZY_CPU); 573 } 574 575 #ifdef CONFIG_X86_64 576 static void xen_load_gs_index(unsigned int idx) 577 { 578 if (HYPERVISOR_set_segment_base(SEGBASE_GS_USER_SEL, idx)) 579 BUG(); 580 } 581 #endif 582 583 static void xen_write_ldt_entry(struct desc_struct *dt, int entrynum, 584 const void *ptr) 585 { 586 xmaddr_t mach_lp = arbitrary_virt_to_machine(&dt[entrynum]); 587 u64 entry = *(u64 *)ptr; 588 589 trace_xen_cpu_write_ldt_entry(dt, entrynum, entry); 590 591 preempt_disable(); 592 593 xen_mc_flush(); 594 if (HYPERVISOR_update_descriptor(mach_lp.maddr, entry)) 595 BUG(); 596 597 preempt_enable(); 598 } 599 600 #ifdef CONFIG_X86_64 601 struct trap_array_entry { 602 void (*orig)(void); 603 void (*xen)(void); 604 bool ist_okay; 605 }; 606 607 #define TRAP_ENTRY(func, ist_ok) { \ 608 .orig = asm_##func, \ 609 .xen = xen_asm_##func, \ 610 .ist_okay = ist_ok } 611 612 #define TRAP_ENTRY_REDIR(func, xenfunc, ist_ok) { \ 613 .orig = asm_##func, \ 614 .xen = xen_asm_##xenfunc, \ 615 .ist_okay = ist_ok } 616 617 static struct trap_array_entry trap_array[] = { 618 TRAP_ENTRY_REDIR(exc_debug, exc_xendebug, true ), 619 TRAP_ENTRY(exc_double_fault, true ), 620 #ifdef CONFIG_X86_MCE 621 TRAP_ENTRY(exc_machine_check, true ), 622 #endif 623 TRAP_ENTRY_REDIR(exc_nmi, exc_xennmi, true ), 624 TRAP_ENTRY(exc_int3, false ), 625 TRAP_ENTRY(exc_overflow, false ), 626 #ifdef CONFIG_IA32_EMULATION 627 { entry_INT80_compat, xen_entry_INT80_compat, false }, 628 #endif 629 TRAP_ENTRY(exc_page_fault, false ), 630 TRAP_ENTRY(exc_divide_error, false ), 631 TRAP_ENTRY(exc_bounds, false ), 632 TRAP_ENTRY(exc_invalid_op, false ), 633 TRAP_ENTRY(exc_device_not_available, false ), 634 TRAP_ENTRY(exc_coproc_segment_overrun, false ), 635 TRAP_ENTRY(exc_invalid_tss, false ), 636 TRAP_ENTRY(exc_segment_not_present, false ), 637 TRAP_ENTRY(exc_stack_segment, false ), 638 TRAP_ENTRY(exc_general_protection, false ), 639 TRAP_ENTRY(exc_spurious_interrupt_bug, false ), 640 TRAP_ENTRY(exc_coprocessor_error, false ), 641 TRAP_ENTRY(exc_alignment_check, false ), 642 TRAP_ENTRY(exc_simd_coprocessor_error, false ), 643 }; 644 645 static bool __ref get_trap_addr(void **addr, unsigned int ist) 646 { 647 unsigned int nr; 648 bool ist_okay = false; 649 650 /* 651 * Replace trap handler addresses by Xen specific ones. 652 * Check for known traps using IST and whitelist them. 653 * The debugger ones are the only ones we care about. 654 * Xen will handle faults like double_fault, so we should never see 655 * them. Warn if there's an unexpected IST-using fault handler. 656 */ 657 for (nr = 0; nr < ARRAY_SIZE(trap_array); nr++) { 658 struct trap_array_entry *entry = trap_array + nr; 659 660 if (*addr == entry->orig) { 661 *addr = entry->xen; 662 ist_okay = entry->ist_okay; 663 break; 664 } 665 } 666 667 if (nr == ARRAY_SIZE(trap_array) && 668 *addr >= (void *)early_idt_handler_array[0] && 669 *addr < (void *)early_idt_handler_array[NUM_EXCEPTION_VECTORS]) { 670 nr = (*addr - (void *)early_idt_handler_array[0]) / 671 EARLY_IDT_HANDLER_SIZE; 672 *addr = (void *)xen_early_idt_handler_array[nr]; 673 } 674 675 if (WARN_ON(ist != 0 && !ist_okay)) 676 return false; 677 678 return true; 679 } 680 #endif 681 682 static int cvt_gate_to_trap(int vector, const gate_desc *val, 683 struct trap_info *info) 684 { 685 unsigned long addr; 686 687 if (val->bits.type != GATE_TRAP && val->bits.type != GATE_INTERRUPT) 688 return 0; 689 690 info->vector = vector; 691 692 addr = gate_offset(val); 693 #ifdef CONFIG_X86_64 694 if (!get_trap_addr((void **)&addr, val->bits.ist)) 695 return 0; 696 #endif /* CONFIG_X86_64 */ 697 info->address = addr; 698 699 info->cs = gate_segment(val); 700 info->flags = val->bits.dpl; 701 /* interrupt gates clear IF */ 702 if (val->bits.type == GATE_INTERRUPT) 703 info->flags |= 1 << 2; 704 705 return 1; 706 } 707 708 /* Locations of each CPU's IDT */ 709 static DEFINE_PER_CPU(struct desc_ptr, idt_desc); 710 711 /* Set an IDT entry. If the entry is part of the current IDT, then 712 also update Xen. */ 713 static void xen_write_idt_entry(gate_desc *dt, int entrynum, const gate_desc *g) 714 { 715 unsigned long p = (unsigned long)&dt[entrynum]; 716 unsigned long start, end; 717 718 trace_xen_cpu_write_idt_entry(dt, entrynum, g); 719 720 preempt_disable(); 721 722 start = __this_cpu_read(idt_desc.address); 723 end = start + __this_cpu_read(idt_desc.size) + 1; 724 725 xen_mc_flush(); 726 727 native_write_idt_entry(dt, entrynum, g); 728 729 if (p >= start && (p + 8) <= end) { 730 struct trap_info info[2]; 731 732 info[1].address = 0; 733 734 if (cvt_gate_to_trap(entrynum, g, &info[0])) 735 if (HYPERVISOR_set_trap_table(info)) 736 BUG(); 737 } 738 739 preempt_enable(); 740 } 741 742 static void xen_convert_trap_info(const struct desc_ptr *desc, 743 struct trap_info *traps) 744 { 745 unsigned in, out, count; 746 747 count = (desc->size+1) / sizeof(gate_desc); 748 BUG_ON(count > 256); 749 750 for (in = out = 0; in < count; in++) { 751 gate_desc *entry = (gate_desc *)(desc->address) + in; 752 753 if (cvt_gate_to_trap(in, entry, &traps[out])) 754 out++; 755 } 756 traps[out].address = 0; 757 } 758 759 void xen_copy_trap_info(struct trap_info *traps) 760 { 761 const struct desc_ptr *desc = this_cpu_ptr(&idt_desc); 762 763 xen_convert_trap_info(desc, traps); 764 } 765 766 /* Load a new IDT into Xen. In principle this can be per-CPU, so we 767 hold a spinlock to protect the static traps[] array (static because 768 it avoids allocation, and saves stack space). */ 769 static void xen_load_idt(const struct desc_ptr *desc) 770 { 771 static DEFINE_SPINLOCK(lock); 772 static struct trap_info traps[257]; 773 774 trace_xen_cpu_load_idt(desc); 775 776 spin_lock(&lock); 777 778 memcpy(this_cpu_ptr(&idt_desc), desc, sizeof(idt_desc)); 779 780 xen_convert_trap_info(desc, traps); 781 782 xen_mc_flush(); 783 if (HYPERVISOR_set_trap_table(traps)) 784 BUG(); 785 786 spin_unlock(&lock); 787 } 788 789 /* Write a GDT descriptor entry. Ignore LDT descriptors, since 790 they're handled differently. */ 791 static void xen_write_gdt_entry(struct desc_struct *dt, int entry, 792 const void *desc, int type) 793 { 794 trace_xen_cpu_write_gdt_entry(dt, entry, desc, type); 795 796 preempt_disable(); 797 798 switch (type) { 799 case DESC_LDT: 800 case DESC_TSS: 801 /* ignore */ 802 break; 803 804 default: { 805 xmaddr_t maddr = arbitrary_virt_to_machine(&dt[entry]); 806 807 xen_mc_flush(); 808 if (HYPERVISOR_update_descriptor(maddr.maddr, *(u64 *)desc)) 809 BUG(); 810 } 811 812 } 813 814 preempt_enable(); 815 } 816 817 /* 818 * Version of write_gdt_entry for use at early boot-time needed to 819 * update an entry as simply as possible. 820 */ 821 static void __init xen_write_gdt_entry_boot(struct desc_struct *dt, int entry, 822 const void *desc, int type) 823 { 824 trace_xen_cpu_write_gdt_entry(dt, entry, desc, type); 825 826 switch (type) { 827 case DESC_LDT: 828 case DESC_TSS: 829 /* ignore */ 830 break; 831 832 default: { 833 xmaddr_t maddr = virt_to_machine(&dt[entry]); 834 835 if (HYPERVISOR_update_descriptor(maddr.maddr, *(u64 *)desc)) 836 dt[entry] = *(struct desc_struct *)desc; 837 } 838 839 } 840 } 841 842 static void xen_load_sp0(unsigned long sp0) 843 { 844 struct multicall_space mcs; 845 846 mcs = xen_mc_entry(0); 847 MULTI_stack_switch(mcs.mc, __KERNEL_DS, sp0); 848 xen_mc_issue(PARAVIRT_LAZY_CPU); 849 this_cpu_write(cpu_tss_rw.x86_tss.sp0, sp0); 850 } 851 852 #ifdef CONFIG_X86_IOPL_IOPERM 853 static void xen_update_io_bitmap(void) 854 { 855 struct physdev_set_iobitmap iobitmap; 856 struct tss_struct *tss = this_cpu_ptr(&cpu_tss_rw); 857 858 native_tss_update_io_bitmap(); 859 860 iobitmap.bitmap = (uint8_t *)(&tss->x86_tss) + 861 tss->x86_tss.io_bitmap_base; 862 if (tss->x86_tss.io_bitmap_base == IO_BITMAP_OFFSET_INVALID) 863 iobitmap.nr_ports = 0; 864 else 865 iobitmap.nr_ports = IO_BITMAP_BITS; 866 867 HYPERVISOR_physdev_op(PHYSDEVOP_set_iobitmap, &iobitmap); 868 } 869 #endif 870 871 static void xen_io_delay(void) 872 { 873 } 874 875 static DEFINE_PER_CPU(unsigned long, xen_cr0_value); 876 877 static unsigned long xen_read_cr0(void) 878 { 879 unsigned long cr0 = this_cpu_read(xen_cr0_value); 880 881 if (unlikely(cr0 == 0)) { 882 cr0 = native_read_cr0(); 883 this_cpu_write(xen_cr0_value, cr0); 884 } 885 886 return cr0; 887 } 888 889 static void xen_write_cr0(unsigned long cr0) 890 { 891 struct multicall_space mcs; 892 893 this_cpu_write(xen_cr0_value, cr0); 894 895 /* Only pay attention to cr0.TS; everything else is 896 ignored. */ 897 mcs = xen_mc_entry(0); 898 899 MULTI_fpu_taskswitch(mcs.mc, (cr0 & X86_CR0_TS) != 0); 900 901 xen_mc_issue(PARAVIRT_LAZY_CPU); 902 } 903 904 static void xen_write_cr4(unsigned long cr4) 905 { 906 cr4 &= ~(X86_CR4_PGE | X86_CR4_PSE | X86_CR4_PCE); 907 908 native_write_cr4(cr4); 909 } 910 911 static u64 xen_read_msr_safe(unsigned int msr, int *err) 912 { 913 u64 val; 914 915 if (pmu_msr_read(msr, &val, err)) 916 return val; 917 918 val = native_read_msr_safe(msr, err); 919 switch (msr) { 920 case MSR_IA32_APICBASE: 921 val &= ~X2APIC_ENABLE; 922 break; 923 } 924 return val; 925 } 926 927 static int xen_write_msr_safe(unsigned int msr, unsigned low, unsigned high) 928 { 929 int ret; 930 #ifdef CONFIG_X86_64 931 unsigned int which; 932 u64 base; 933 #endif 934 935 ret = 0; 936 937 switch (msr) { 938 #ifdef CONFIG_X86_64 939 case MSR_FS_BASE: which = SEGBASE_FS; goto set; 940 case MSR_KERNEL_GS_BASE: which = SEGBASE_GS_USER; goto set; 941 case MSR_GS_BASE: which = SEGBASE_GS_KERNEL; goto set; 942 943 set: 944 base = ((u64)high << 32) | low; 945 if (HYPERVISOR_set_segment_base(which, base) != 0) 946 ret = -EIO; 947 break; 948 #endif 949 950 case MSR_STAR: 951 case MSR_CSTAR: 952 case MSR_LSTAR: 953 case MSR_SYSCALL_MASK: 954 case MSR_IA32_SYSENTER_CS: 955 case MSR_IA32_SYSENTER_ESP: 956 case MSR_IA32_SYSENTER_EIP: 957 /* Fast syscall setup is all done in hypercalls, so 958 these are all ignored. Stub them out here to stop 959 Xen console noise. */ 960 break; 961 962 default: 963 if (!pmu_msr_write(msr, low, high, &ret)) 964 ret = native_write_msr_safe(msr, low, high); 965 } 966 967 return ret; 968 } 969 970 static u64 xen_read_msr(unsigned int msr) 971 { 972 /* 973 * This will silently swallow a #GP from RDMSR. It may be worth 974 * changing that. 975 */ 976 int err; 977 978 return xen_read_msr_safe(msr, &err); 979 } 980 981 static void xen_write_msr(unsigned int msr, unsigned low, unsigned high) 982 { 983 /* 984 * This will silently swallow a #GP from WRMSR. It may be worth 985 * changing that. 986 */ 987 xen_write_msr_safe(msr, low, high); 988 } 989 990 /* This is called once we have the cpu_possible_mask */ 991 void __init xen_setup_vcpu_info_placement(void) 992 { 993 int cpu; 994 995 for_each_possible_cpu(cpu) { 996 /* Set up direct vCPU id mapping for PV guests. */ 997 per_cpu(xen_vcpu_id, cpu) = cpu; 998 999 /* 1000 * xen_vcpu_setup(cpu) can fail -- in which case it 1001 * falls back to the shared_info version for cpus 1002 * where xen_vcpu_nr(cpu) < MAX_VIRT_CPUS. 1003 * 1004 * xen_cpu_up_prepare_pv() handles the rest by failing 1005 * them in hotplug. 1006 */ 1007 (void) xen_vcpu_setup(cpu); 1008 } 1009 1010 /* 1011 * xen_vcpu_setup managed to place the vcpu_info within the 1012 * percpu area for all cpus, so make use of it. 1013 */ 1014 if (xen_have_vcpu_info_placement) { 1015 pv_ops.irq.save_fl = __PV_IS_CALLEE_SAVE(xen_save_fl_direct); 1016 pv_ops.irq.restore_fl = 1017 __PV_IS_CALLEE_SAVE(xen_restore_fl_direct); 1018 pv_ops.irq.irq_disable = 1019 __PV_IS_CALLEE_SAVE(xen_irq_disable_direct); 1020 pv_ops.irq.irq_enable = 1021 __PV_IS_CALLEE_SAVE(xen_irq_enable_direct); 1022 pv_ops.mmu.read_cr2 = 1023 __PV_IS_CALLEE_SAVE(xen_read_cr2_direct); 1024 } 1025 } 1026 1027 static const struct pv_info xen_info __initconst = { 1028 .shared_kernel_pmd = 0, 1029 1030 #ifdef CONFIG_X86_64 1031 .extra_user_64bit_cs = FLAT_USER_CS64, 1032 #endif 1033 .name = "Xen", 1034 }; 1035 1036 static const struct pv_cpu_ops xen_cpu_ops __initconst = { 1037 .cpuid = xen_cpuid, 1038 1039 .set_debugreg = xen_set_debugreg, 1040 .get_debugreg = xen_get_debugreg, 1041 1042 .read_cr0 = xen_read_cr0, 1043 .write_cr0 = xen_write_cr0, 1044 1045 .write_cr4 = xen_write_cr4, 1046 1047 .wbinvd = native_wbinvd, 1048 1049 .read_msr = xen_read_msr, 1050 .write_msr = xen_write_msr, 1051 1052 .read_msr_safe = xen_read_msr_safe, 1053 .write_msr_safe = xen_write_msr_safe, 1054 1055 .read_pmc = xen_read_pmc, 1056 1057 .iret = xen_iret, 1058 #ifdef CONFIG_X86_64 1059 .usergs_sysret64 = xen_sysret64, 1060 #endif 1061 1062 .load_tr_desc = paravirt_nop, 1063 .set_ldt = xen_set_ldt, 1064 .load_gdt = xen_load_gdt, 1065 .load_idt = xen_load_idt, 1066 .load_tls = xen_load_tls, 1067 #ifdef CONFIG_X86_64 1068 .load_gs_index = xen_load_gs_index, 1069 #endif 1070 1071 .alloc_ldt = xen_alloc_ldt, 1072 .free_ldt = xen_free_ldt, 1073 1074 .store_tr = xen_store_tr, 1075 1076 .write_ldt_entry = xen_write_ldt_entry, 1077 .write_gdt_entry = xen_write_gdt_entry, 1078 .write_idt_entry = xen_write_idt_entry, 1079 .load_sp0 = xen_load_sp0, 1080 1081 #ifdef CONFIG_X86_IOPL_IOPERM 1082 .update_io_bitmap = xen_update_io_bitmap, 1083 #endif 1084 .io_delay = xen_io_delay, 1085 1086 /* Xen takes care of %gs when switching to usermode for us */ 1087 .swapgs = paravirt_nop, 1088 1089 .start_context_switch = paravirt_start_context_switch, 1090 .end_context_switch = xen_end_context_switch, 1091 }; 1092 1093 static void xen_restart(char *msg) 1094 { 1095 xen_reboot(SHUTDOWN_reboot); 1096 } 1097 1098 static void xen_machine_halt(void) 1099 { 1100 xen_reboot(SHUTDOWN_poweroff); 1101 } 1102 1103 static void xen_machine_power_off(void) 1104 { 1105 if (pm_power_off) 1106 pm_power_off(); 1107 xen_reboot(SHUTDOWN_poweroff); 1108 } 1109 1110 static void xen_crash_shutdown(struct pt_regs *regs) 1111 { 1112 xen_reboot(SHUTDOWN_crash); 1113 } 1114 1115 static const struct machine_ops xen_machine_ops __initconst = { 1116 .restart = xen_restart, 1117 .halt = xen_machine_halt, 1118 .power_off = xen_machine_power_off, 1119 .shutdown = xen_machine_halt, 1120 .crash_shutdown = xen_crash_shutdown, 1121 .emergency_restart = xen_emergency_restart, 1122 }; 1123 1124 static unsigned char xen_get_nmi_reason(void) 1125 { 1126 unsigned char reason = 0; 1127 1128 /* Construct a value which looks like it came from port 0x61. */ 1129 if (test_bit(_XEN_NMIREASON_io_error, 1130 &HYPERVISOR_shared_info->arch.nmi_reason)) 1131 reason |= NMI_REASON_IOCHK; 1132 if (test_bit(_XEN_NMIREASON_pci_serr, 1133 &HYPERVISOR_shared_info->arch.nmi_reason)) 1134 reason |= NMI_REASON_SERR; 1135 1136 return reason; 1137 } 1138 1139 static void __init xen_boot_params_init_edd(void) 1140 { 1141 #if IS_ENABLED(CONFIG_EDD) 1142 struct xen_platform_op op; 1143 struct edd_info *edd_info; 1144 u32 *mbr_signature; 1145 unsigned nr; 1146 int ret; 1147 1148 edd_info = boot_params.eddbuf; 1149 mbr_signature = boot_params.edd_mbr_sig_buffer; 1150 1151 op.cmd = XENPF_firmware_info; 1152 1153 op.u.firmware_info.type = XEN_FW_DISK_INFO; 1154 for (nr = 0; nr < EDDMAXNR; nr++) { 1155 struct edd_info *info = edd_info + nr; 1156 1157 op.u.firmware_info.index = nr; 1158 info->params.length = sizeof(info->params); 1159 set_xen_guest_handle(op.u.firmware_info.u.disk_info.edd_params, 1160 &info->params); 1161 ret = HYPERVISOR_platform_op(&op); 1162 if (ret) 1163 break; 1164 1165 #define C(x) info->x = op.u.firmware_info.u.disk_info.x 1166 C(device); 1167 C(version); 1168 C(interface_support); 1169 C(legacy_max_cylinder); 1170 C(legacy_max_head); 1171 C(legacy_sectors_per_track); 1172 #undef C 1173 } 1174 boot_params.eddbuf_entries = nr; 1175 1176 op.u.firmware_info.type = XEN_FW_DISK_MBR_SIGNATURE; 1177 for (nr = 0; nr < EDD_MBR_SIG_MAX; nr++) { 1178 op.u.firmware_info.index = nr; 1179 ret = HYPERVISOR_platform_op(&op); 1180 if (ret) 1181 break; 1182 mbr_signature[nr] = op.u.firmware_info.u.disk_mbr_signature.mbr_signature; 1183 } 1184 boot_params.edd_mbr_sig_buf_entries = nr; 1185 #endif 1186 } 1187 1188 /* 1189 * Set up the GDT and segment registers for -fstack-protector. Until 1190 * we do this, we have to be careful not to call any stack-protected 1191 * function, which is most of the kernel. 1192 */ 1193 static void __init xen_setup_gdt(int cpu) 1194 { 1195 pv_ops.cpu.write_gdt_entry = xen_write_gdt_entry_boot; 1196 pv_ops.cpu.load_gdt = xen_load_gdt_boot; 1197 1198 setup_stack_canary_segment(cpu); 1199 switch_to_new_gdt(cpu); 1200 1201 pv_ops.cpu.write_gdt_entry = xen_write_gdt_entry; 1202 pv_ops.cpu.load_gdt = xen_load_gdt; 1203 } 1204 1205 static void __init xen_dom0_set_legacy_features(void) 1206 { 1207 x86_platform.legacy.rtc = 1; 1208 } 1209 1210 /* First C function to be called on Xen boot */ 1211 asmlinkage __visible void __init xen_start_kernel(void) 1212 { 1213 struct physdev_set_iopl set_iopl; 1214 unsigned long initrd_start = 0; 1215 int rc; 1216 1217 if (!xen_start_info) 1218 return; 1219 1220 xen_domain_type = XEN_PV_DOMAIN; 1221 xen_start_flags = xen_start_info->flags; 1222 1223 xen_setup_features(); 1224 1225 /* Install Xen paravirt ops */ 1226 pv_info = xen_info; 1227 pv_ops.init.patch = paravirt_patch_default; 1228 pv_ops.cpu = xen_cpu_ops; 1229 xen_init_irq_ops(); 1230 1231 /* 1232 * Setup xen_vcpu early because it is needed for 1233 * local_irq_disable(), irqs_disabled(), e.g. in printk(). 1234 * 1235 * Don't do the full vcpu_info placement stuff until we have 1236 * the cpu_possible_mask and a non-dummy shared_info. 1237 */ 1238 xen_vcpu_info_reset(0); 1239 1240 x86_platform.get_nmi_reason = xen_get_nmi_reason; 1241 1242 x86_init.resources.memory_setup = xen_memory_setup; 1243 x86_init.irqs.intr_mode_select = x86_init_noop; 1244 x86_init.irqs.intr_mode_init = x86_init_noop; 1245 x86_init.oem.arch_setup = xen_arch_setup; 1246 x86_init.oem.banner = xen_banner; 1247 x86_init.hyper.init_platform = xen_pv_init_platform; 1248 x86_init.hyper.guest_late_init = xen_pv_guest_late_init; 1249 1250 /* 1251 * Set up some pagetable state before starting to set any ptes. 1252 */ 1253 1254 xen_setup_machphys_mapping(); 1255 xen_init_mmu_ops(); 1256 1257 /* Prevent unwanted bits from being set in PTEs. */ 1258 __supported_pte_mask &= ~_PAGE_GLOBAL; 1259 __default_kernel_pte_mask &= ~_PAGE_GLOBAL; 1260 1261 /* 1262 * Prevent page tables from being allocated in highmem, even 1263 * if CONFIG_HIGHPTE is enabled. 1264 */ 1265 __userpte_alloc_gfp &= ~__GFP_HIGHMEM; 1266 1267 /* Get mfn list */ 1268 xen_build_dynamic_phys_to_machine(); 1269 1270 /* 1271 * Set up kernel GDT and segment registers, mainly so that 1272 * -fstack-protector code can be executed. 1273 */ 1274 xen_setup_gdt(0); 1275 1276 /* Work out if we support NX */ 1277 get_cpu_cap(&boot_cpu_data); 1278 x86_configure_nx(); 1279 1280 /* Determine virtual and physical address sizes */ 1281 get_cpu_address_sizes(&boot_cpu_data); 1282 1283 /* Let's presume PV guests always boot on vCPU with id 0. */ 1284 per_cpu(xen_vcpu_id, 0) = 0; 1285 1286 idt_setup_early_handler(); 1287 1288 xen_init_capabilities(); 1289 1290 #ifdef CONFIG_X86_LOCAL_APIC 1291 /* 1292 * set up the basic apic ops. 1293 */ 1294 xen_init_apic(); 1295 #endif 1296 1297 if (xen_feature(XENFEAT_mmu_pt_update_preserve_ad)) { 1298 pv_ops.mmu.ptep_modify_prot_start = 1299 xen_ptep_modify_prot_start; 1300 pv_ops.mmu.ptep_modify_prot_commit = 1301 xen_ptep_modify_prot_commit; 1302 } 1303 1304 machine_ops = xen_machine_ops; 1305 1306 /* 1307 * The only reliable way to retain the initial address of the 1308 * percpu gdt_page is to remember it here, so we can go and 1309 * mark it RW later, when the initial percpu area is freed. 1310 */ 1311 xen_initial_gdt = &per_cpu(gdt_page, 0); 1312 1313 xen_smp_init(); 1314 1315 #ifdef CONFIG_ACPI_NUMA 1316 /* 1317 * The pages we from Xen are not related to machine pages, so 1318 * any NUMA information the kernel tries to get from ACPI will 1319 * be meaningless. Prevent it from trying. 1320 */ 1321 acpi_numa = -1; 1322 #endif 1323 WARN_ON(xen_cpuhp_setup(xen_cpu_up_prepare_pv, xen_cpu_dead_pv)); 1324 1325 local_irq_disable(); 1326 early_boot_irqs_disabled = true; 1327 1328 xen_raw_console_write("mapping kernel into physical memory\n"); 1329 xen_setup_kernel_pagetable((pgd_t *)xen_start_info->pt_base, 1330 xen_start_info->nr_pages); 1331 xen_reserve_special_pages(); 1332 1333 /* keep using Xen gdt for now; no urgent need to change it */ 1334 1335 #ifdef CONFIG_X86_32 1336 pv_info.kernel_rpl = 1; 1337 if (xen_feature(XENFEAT_supervisor_mode_kernel)) 1338 pv_info.kernel_rpl = 0; 1339 #else 1340 pv_info.kernel_rpl = 0; 1341 #endif 1342 /* set the limit of our address space */ 1343 xen_reserve_top(); 1344 1345 /* 1346 * We used to do this in xen_arch_setup, but that is too late 1347 * on AMD were early_cpu_init (run before ->arch_setup()) calls 1348 * early_amd_init which pokes 0xcf8 port. 1349 */ 1350 set_iopl.iopl = 1; 1351 rc = HYPERVISOR_physdev_op(PHYSDEVOP_set_iopl, &set_iopl); 1352 if (rc != 0) 1353 xen_raw_printk("physdev_op failed %d\n", rc); 1354 1355 #ifdef CONFIG_X86_32 1356 /* set up basic CPUID stuff */ 1357 cpu_detect(&new_cpu_data); 1358 set_cpu_cap(&new_cpu_data, X86_FEATURE_FPU); 1359 new_cpu_data.x86_capability[CPUID_1_EDX] = cpuid_edx(1); 1360 #endif 1361 1362 if (xen_start_info->mod_start) { 1363 if (xen_start_info->flags & SIF_MOD_START_PFN) 1364 initrd_start = PFN_PHYS(xen_start_info->mod_start); 1365 else 1366 initrd_start = __pa(xen_start_info->mod_start); 1367 } 1368 1369 /* Poke various useful things into boot_params */ 1370 boot_params.hdr.type_of_loader = (9 << 4) | 0; 1371 boot_params.hdr.ramdisk_image = initrd_start; 1372 boot_params.hdr.ramdisk_size = xen_start_info->mod_len; 1373 boot_params.hdr.cmd_line_ptr = __pa(xen_start_info->cmd_line); 1374 boot_params.hdr.hardware_subarch = X86_SUBARCH_XEN; 1375 1376 if (!xen_initial_domain()) { 1377 add_preferred_console("xenboot", 0, NULL); 1378 if (pci_xen) 1379 x86_init.pci.arch_init = pci_xen_init; 1380 } else { 1381 const struct dom0_vga_console_info *info = 1382 (void *)((char *)xen_start_info + 1383 xen_start_info->console.dom0.info_off); 1384 struct xen_platform_op op = { 1385 .cmd = XENPF_firmware_info, 1386 .interface_version = XENPF_INTERFACE_VERSION, 1387 .u.firmware_info.type = XEN_FW_KBD_SHIFT_FLAGS, 1388 }; 1389 1390 x86_platform.set_legacy_features = 1391 xen_dom0_set_legacy_features; 1392 xen_init_vga(info, xen_start_info->console.dom0.info_size); 1393 xen_start_info->console.domU.mfn = 0; 1394 xen_start_info->console.domU.evtchn = 0; 1395 1396 if (HYPERVISOR_platform_op(&op) == 0) 1397 boot_params.kbd_status = op.u.firmware_info.u.kbd_shift_flags; 1398 1399 /* Make sure ACS will be enabled */ 1400 pci_request_acs(); 1401 1402 xen_acpi_sleep_register(); 1403 1404 /* Avoid searching for BIOS MP tables */ 1405 x86_init.mpparse.find_smp_config = x86_init_noop; 1406 x86_init.mpparse.get_smp_config = x86_init_uint_noop; 1407 1408 xen_boot_params_init_edd(); 1409 } 1410 1411 if (!boot_params.screen_info.orig_video_isVGA) 1412 add_preferred_console("tty", 0, NULL); 1413 add_preferred_console("hvc", 0, NULL); 1414 if (boot_params.screen_info.orig_video_isVGA) 1415 add_preferred_console("tty", 0, NULL); 1416 1417 #ifdef CONFIG_PCI 1418 /* PCI BIOS service won't work from a PV guest. */ 1419 pci_probe &= ~PCI_PROBE_BIOS; 1420 #endif 1421 xen_raw_console_write("about to get started...\n"); 1422 1423 /* We need this for printk timestamps */ 1424 xen_setup_runstate_info(0); 1425 1426 xen_efi_init(&boot_params); 1427 1428 /* Start the world */ 1429 #ifdef CONFIG_X86_32 1430 i386_start_kernel(); 1431 #else 1432 cr4_init_shadow(); /* 32b kernel does this in i386_start_kernel() */ 1433 x86_64_start_reservations((char *)__pa_symbol(&boot_params)); 1434 #endif 1435 } 1436 1437 static int xen_cpu_up_prepare_pv(unsigned int cpu) 1438 { 1439 int rc; 1440 1441 if (per_cpu(xen_vcpu, cpu) == NULL) 1442 return -ENODEV; 1443 1444 xen_setup_timer(cpu); 1445 1446 rc = xen_smp_intr_init(cpu); 1447 if (rc) { 1448 WARN(1, "xen_smp_intr_init() for CPU %d failed: %d\n", 1449 cpu, rc); 1450 return rc; 1451 } 1452 1453 rc = xen_smp_intr_init_pv(cpu); 1454 if (rc) { 1455 WARN(1, "xen_smp_intr_init_pv() for CPU %d failed: %d\n", 1456 cpu, rc); 1457 return rc; 1458 } 1459 1460 return 0; 1461 } 1462 1463 static int xen_cpu_dead_pv(unsigned int cpu) 1464 { 1465 xen_smp_intr_free(cpu); 1466 xen_smp_intr_free_pv(cpu); 1467 1468 xen_teardown_timer(cpu); 1469 1470 return 0; 1471 } 1472 1473 static uint32_t __init xen_platform_pv(void) 1474 { 1475 if (xen_pv_domain()) 1476 return xen_cpuid_base(); 1477 1478 return 0; 1479 } 1480 1481 const __initconst struct hypervisor_x86 x86_hyper_xen_pv = { 1482 .name = "Xen PV", 1483 .detect = xen_platform_pv, 1484 .type = X86_HYPER_XEN_PV, 1485 .runtime.pin_vcpu = xen_pin_vcpu, 1486 .ignore_nopv = true, 1487 }; 1488