xref: /linux/arch/x86/include/asm/processor.h (revision be239684b18e1cdcafcf8c7face4a2f562c745ad)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _ASM_X86_PROCESSOR_H
3 #define _ASM_X86_PROCESSOR_H
4 
5 #include <asm/processor-flags.h>
6 
7 /* Forward declaration, a strange C thing */
8 struct task_struct;
9 struct mm_struct;
10 struct io_bitmap;
11 struct vm86;
12 
13 #include <asm/math_emu.h>
14 #include <asm/segment.h>
15 #include <asm/types.h>
16 #include <uapi/asm/sigcontext.h>
17 #include <asm/current.h>
18 #include <asm/cpufeatures.h>
19 #include <asm/cpuid.h>
20 #include <asm/page.h>
21 #include <asm/pgtable_types.h>
22 #include <asm/percpu.h>
23 #include <asm/msr.h>
24 #include <asm/desc_defs.h>
25 #include <asm/nops.h>
26 #include <asm/special_insns.h>
27 #include <asm/fpu/types.h>
28 #include <asm/unwind_hints.h>
29 #include <asm/vmxfeatures.h>
30 #include <asm/vdso/processor.h>
31 #include <asm/shstk.h>
32 
33 #include <linux/personality.h>
34 #include <linux/cache.h>
35 #include <linux/threads.h>
36 #include <linux/math64.h>
37 #include <linux/err.h>
38 #include <linux/irqflags.h>
39 #include <linux/mem_encrypt.h>
40 
41 /*
42  * We handle most unaligned accesses in hardware.  On the other hand
43  * unaligned DMA can be quite expensive on some Nehalem processors.
44  *
45  * Based on this we disable the IP header alignment in network drivers.
46  */
47 #define NET_IP_ALIGN	0
48 
49 #define HBP_NUM 4
50 
51 /*
52  * These alignment constraints are for performance in the vSMP case,
53  * but in the task_struct case we must also meet hardware imposed
54  * alignment requirements of the FPU state:
55  */
56 #ifdef CONFIG_X86_VSMP
57 # define ARCH_MIN_TASKALIGN		(1 << INTERNODE_CACHE_SHIFT)
58 # define ARCH_MIN_MMSTRUCT_ALIGN	(1 << INTERNODE_CACHE_SHIFT)
59 #else
60 # define ARCH_MIN_TASKALIGN		__alignof__(union fpregs_state)
61 # define ARCH_MIN_MMSTRUCT_ALIGN	0
62 #endif
63 
64 enum tlb_infos {
65 	ENTRIES,
66 	NR_INFO
67 };
68 
69 extern u16 __read_mostly tlb_lli_4k[NR_INFO];
70 extern u16 __read_mostly tlb_lli_2m[NR_INFO];
71 extern u16 __read_mostly tlb_lli_4m[NR_INFO];
72 extern u16 __read_mostly tlb_lld_4k[NR_INFO];
73 extern u16 __read_mostly tlb_lld_2m[NR_INFO];
74 extern u16 __read_mostly tlb_lld_4m[NR_INFO];
75 extern u16 __read_mostly tlb_lld_1g[NR_INFO];
76 
77 /*
78  * CPU type and hardware bug flags. Kept separately for each CPU.
79  */
80 
81 struct cpuinfo_topology {
82 	// Real APIC ID read from the local APIC
83 	u32			apicid;
84 	// The initial APIC ID provided by CPUID
85 	u32			initial_apicid;
86 
87 	// Physical package ID
88 	u32			pkg_id;
89 
90 	// Physical die ID on AMD, Relative on Intel
91 	u32			die_id;
92 
93 	// Compute unit ID - AMD specific
94 	u32			cu_id;
95 
96 	// Core ID relative to the package
97 	u32			core_id;
98 
99 	// Logical ID mappings
100 	u32			logical_pkg_id;
101 	u32			logical_die_id;
102 
103 	// Cache level topology IDs
104 	u32			llc_id;
105 	u32			l2c_id;
106 };
107 
108 struct cpuinfo_x86 {
109 	__u8			x86;		/* CPU family */
110 	__u8			x86_vendor;	/* CPU vendor */
111 	__u8			x86_model;
112 	__u8			x86_stepping;
113 #ifdef CONFIG_X86_64
114 	/* Number of 4K pages in DTLB/ITLB combined(in pages): */
115 	int			x86_tlbsize;
116 #endif
117 #ifdef CONFIG_X86_VMX_FEATURE_NAMES
118 	__u32			vmx_capability[NVMXINTS];
119 #endif
120 	__u8			x86_virt_bits;
121 	__u8			x86_phys_bits;
122 	/* CPUID returned core id bits: */
123 	__u8			x86_coreid_bits;
124 	/* Max extended CPUID function supported: */
125 	__u32			extended_cpuid_level;
126 	/* Maximum supported CPUID level, -1=no CPUID: */
127 	int			cpuid_level;
128 	/*
129 	 * Align to size of unsigned long because the x86_capability array
130 	 * is passed to bitops which require the alignment. Use unnamed
131 	 * union to enforce the array is aligned to size of unsigned long.
132 	 */
133 	union {
134 		__u32		x86_capability[NCAPINTS + NBUGINTS];
135 		unsigned long	x86_capability_alignment;
136 	};
137 	char			x86_vendor_id[16];
138 	char			x86_model_id[64];
139 	struct cpuinfo_topology	topo;
140 	/* in KB - valid for CPUS which support this call: */
141 	unsigned int		x86_cache_size;
142 	int			x86_cache_alignment;	/* In bytes */
143 	/* Cache QoS architectural values, valid only on the BSP: */
144 	int			x86_cache_max_rmid;	/* max index */
145 	int			x86_cache_occ_scale;	/* scale to bytes */
146 	int			x86_cache_mbm_width_offset;
147 	int			x86_power;
148 	unsigned long		loops_per_jiffy;
149 	/* protected processor identification number */
150 	u64			ppin;
151 	/* cpuid returned max cores value: */
152 	u16			x86_max_cores;
153 	u16			x86_clflush_size;
154 	/* number of cores as seen by the OS: */
155 	u16			booted_cores;
156 	/* Index into per_cpu list: */
157 	u16			cpu_index;
158 	/*  Is SMT active on this core? */
159 	bool			smt_active;
160 	u32			microcode;
161 	/* Address space bits used by the cache internally */
162 	u8			x86_cache_bits;
163 	unsigned		initialized : 1;
164 } __randomize_layout;
165 
166 #define X86_VENDOR_INTEL	0
167 #define X86_VENDOR_CYRIX	1
168 #define X86_VENDOR_AMD		2
169 #define X86_VENDOR_UMC		3
170 #define X86_VENDOR_CENTAUR	5
171 #define X86_VENDOR_TRANSMETA	7
172 #define X86_VENDOR_NSC		8
173 #define X86_VENDOR_HYGON	9
174 #define X86_VENDOR_ZHAOXIN	10
175 #define X86_VENDOR_VORTEX	11
176 #define X86_VENDOR_NUM		12
177 
178 #define X86_VENDOR_UNKNOWN	0xff
179 
180 /*
181  * capabilities of CPUs
182  */
183 extern struct cpuinfo_x86	boot_cpu_data;
184 extern struct cpuinfo_x86	new_cpu_data;
185 
186 extern __u32			cpu_caps_cleared[NCAPINTS + NBUGINTS];
187 extern __u32			cpu_caps_set[NCAPINTS + NBUGINTS];
188 
189 #ifdef CONFIG_SMP
190 DECLARE_PER_CPU_READ_MOSTLY(struct cpuinfo_x86, cpu_info);
191 #define cpu_data(cpu)		per_cpu(cpu_info, cpu)
192 #else
193 #define cpu_info		boot_cpu_data
194 #define cpu_data(cpu)		boot_cpu_data
195 #endif
196 
197 extern const struct seq_operations cpuinfo_op;
198 
199 #define cache_line_size()	(boot_cpu_data.x86_cache_alignment)
200 
201 extern void cpu_detect(struct cpuinfo_x86 *c);
202 
203 static inline unsigned long long l1tf_pfn_limit(void)
204 {
205 	return BIT_ULL(boot_cpu_data.x86_cache_bits - 1 - PAGE_SHIFT);
206 }
207 
208 extern void early_cpu_init(void);
209 extern void identify_secondary_cpu(struct cpuinfo_x86 *);
210 extern void print_cpu_info(struct cpuinfo_x86 *);
211 void print_cpu_msr(struct cpuinfo_x86 *);
212 
213 /*
214  * Friendlier CR3 helpers.
215  */
216 static inline unsigned long read_cr3_pa(void)
217 {
218 	return __read_cr3() & CR3_ADDR_MASK;
219 }
220 
221 static inline unsigned long native_read_cr3_pa(void)
222 {
223 	return __native_read_cr3() & CR3_ADDR_MASK;
224 }
225 
226 static inline void load_cr3(pgd_t *pgdir)
227 {
228 	write_cr3(__sme_pa(pgdir));
229 }
230 
231 /*
232  * Note that while the legacy 'TSS' name comes from 'Task State Segment',
233  * on modern x86 CPUs the TSS also holds information important to 64-bit mode,
234  * unrelated to the task-switch mechanism:
235  */
236 #ifdef CONFIG_X86_32
237 /* This is the TSS defined by the hardware. */
238 struct x86_hw_tss {
239 	unsigned short		back_link, __blh;
240 	unsigned long		sp0;
241 	unsigned short		ss0, __ss0h;
242 	unsigned long		sp1;
243 
244 	/*
245 	 * We don't use ring 1, so ss1 is a convenient scratch space in
246 	 * the same cacheline as sp0.  We use ss1 to cache the value in
247 	 * MSR_IA32_SYSENTER_CS.  When we context switch
248 	 * MSR_IA32_SYSENTER_CS, we first check if the new value being
249 	 * written matches ss1, and, if it's not, then we wrmsr the new
250 	 * value and update ss1.
251 	 *
252 	 * The only reason we context switch MSR_IA32_SYSENTER_CS is
253 	 * that we set it to zero in vm86 tasks to avoid corrupting the
254 	 * stack if we were to go through the sysenter path from vm86
255 	 * mode.
256 	 */
257 	unsigned short		ss1;	/* MSR_IA32_SYSENTER_CS */
258 
259 	unsigned short		__ss1h;
260 	unsigned long		sp2;
261 	unsigned short		ss2, __ss2h;
262 	unsigned long		__cr3;
263 	unsigned long		ip;
264 	unsigned long		flags;
265 	unsigned long		ax;
266 	unsigned long		cx;
267 	unsigned long		dx;
268 	unsigned long		bx;
269 	unsigned long		sp;
270 	unsigned long		bp;
271 	unsigned long		si;
272 	unsigned long		di;
273 	unsigned short		es, __esh;
274 	unsigned short		cs, __csh;
275 	unsigned short		ss, __ssh;
276 	unsigned short		ds, __dsh;
277 	unsigned short		fs, __fsh;
278 	unsigned short		gs, __gsh;
279 	unsigned short		ldt, __ldth;
280 	unsigned short		trace;
281 	unsigned short		io_bitmap_base;
282 
283 } __attribute__((packed));
284 #else
285 struct x86_hw_tss {
286 	u32			reserved1;
287 	u64			sp0;
288 	u64			sp1;
289 
290 	/*
291 	 * Since Linux does not use ring 2, the 'sp2' slot is unused by
292 	 * hardware.  entry_SYSCALL_64 uses it as scratch space to stash
293 	 * the user RSP value.
294 	 */
295 	u64			sp2;
296 
297 	u64			reserved2;
298 	u64			ist[7];
299 	u32			reserved3;
300 	u32			reserved4;
301 	u16			reserved5;
302 	u16			io_bitmap_base;
303 
304 } __attribute__((packed));
305 #endif
306 
307 /*
308  * IO-bitmap sizes:
309  */
310 #define IO_BITMAP_BITS			65536
311 #define IO_BITMAP_BYTES			(IO_BITMAP_BITS / BITS_PER_BYTE)
312 #define IO_BITMAP_LONGS			(IO_BITMAP_BYTES / sizeof(long))
313 
314 #define IO_BITMAP_OFFSET_VALID_MAP				\
315 	(offsetof(struct tss_struct, io_bitmap.bitmap) -	\
316 	 offsetof(struct tss_struct, x86_tss))
317 
318 #define IO_BITMAP_OFFSET_VALID_ALL				\
319 	(offsetof(struct tss_struct, io_bitmap.mapall) -	\
320 	 offsetof(struct tss_struct, x86_tss))
321 
322 #ifdef CONFIG_X86_IOPL_IOPERM
323 /*
324  * sizeof(unsigned long) coming from an extra "long" at the end of the
325  * iobitmap. The limit is inclusive, i.e. the last valid byte.
326  */
327 # define __KERNEL_TSS_LIMIT	\
328 	(IO_BITMAP_OFFSET_VALID_ALL + IO_BITMAP_BYTES + \
329 	 sizeof(unsigned long) - 1)
330 #else
331 # define __KERNEL_TSS_LIMIT	\
332 	(offsetof(struct tss_struct, x86_tss) + sizeof(struct x86_hw_tss) - 1)
333 #endif
334 
335 /* Base offset outside of TSS_LIMIT so unpriviledged IO causes #GP */
336 #define IO_BITMAP_OFFSET_INVALID	(__KERNEL_TSS_LIMIT + 1)
337 
338 struct entry_stack {
339 	char	stack[PAGE_SIZE];
340 };
341 
342 struct entry_stack_page {
343 	struct entry_stack stack;
344 } __aligned(PAGE_SIZE);
345 
346 /*
347  * All IO bitmap related data stored in the TSS:
348  */
349 struct x86_io_bitmap {
350 	/* The sequence number of the last active bitmap. */
351 	u64			prev_sequence;
352 
353 	/*
354 	 * Store the dirty size of the last io bitmap offender. The next
355 	 * one will have to do the cleanup as the switch out to a non io
356 	 * bitmap user will just set x86_tss.io_bitmap_base to a value
357 	 * outside of the TSS limit. So for sane tasks there is no need to
358 	 * actually touch the io_bitmap at all.
359 	 */
360 	unsigned int		prev_max;
361 
362 	/*
363 	 * The extra 1 is there because the CPU will access an
364 	 * additional byte beyond the end of the IO permission
365 	 * bitmap. The extra byte must be all 1 bits, and must
366 	 * be within the limit.
367 	 */
368 	unsigned long		bitmap[IO_BITMAP_LONGS + 1];
369 
370 	/*
371 	 * Special I/O bitmap to emulate IOPL(3). All bytes zero,
372 	 * except the additional byte at the end.
373 	 */
374 	unsigned long		mapall[IO_BITMAP_LONGS + 1];
375 };
376 
377 struct tss_struct {
378 	/*
379 	 * The fixed hardware portion.  This must not cross a page boundary
380 	 * at risk of violating the SDM's advice and potentially triggering
381 	 * errata.
382 	 */
383 	struct x86_hw_tss	x86_tss;
384 
385 	struct x86_io_bitmap	io_bitmap;
386 } __aligned(PAGE_SIZE);
387 
388 DECLARE_PER_CPU_PAGE_ALIGNED(struct tss_struct, cpu_tss_rw);
389 
390 /* Per CPU interrupt stacks */
391 struct irq_stack {
392 	char		stack[IRQ_STACK_SIZE];
393 } __aligned(IRQ_STACK_SIZE);
394 
395 #ifdef CONFIG_X86_64
396 struct fixed_percpu_data {
397 	/*
398 	 * GCC hardcodes the stack canary as %gs:40.  Since the
399 	 * irq_stack is the object at %gs:0, we reserve the bottom
400 	 * 48 bytes of the irq stack for the canary.
401 	 *
402 	 * Once we are willing to require -mstack-protector-guard-symbol=
403 	 * support for x86_64 stackprotector, we can get rid of this.
404 	 */
405 	char		gs_base[40];
406 	unsigned long	stack_canary;
407 };
408 
409 DECLARE_PER_CPU_FIRST(struct fixed_percpu_data, fixed_percpu_data) __visible;
410 DECLARE_INIT_PER_CPU(fixed_percpu_data);
411 
412 static inline unsigned long cpu_kernelmode_gs_base(int cpu)
413 {
414 	return (unsigned long)per_cpu(fixed_percpu_data.gs_base, cpu);
415 }
416 
417 extern asmlinkage void entry_SYSCALL32_ignore(void);
418 
419 /* Save actual FS/GS selectors and bases to current->thread */
420 void current_save_fsgs(void);
421 #else	/* X86_64 */
422 #ifdef CONFIG_STACKPROTECTOR
423 DECLARE_PER_CPU(unsigned long, __stack_chk_guard);
424 #endif
425 #endif	/* !X86_64 */
426 
427 struct perf_event;
428 
429 struct thread_struct {
430 	/* Cached TLS descriptors: */
431 	struct desc_struct	tls_array[GDT_ENTRY_TLS_ENTRIES];
432 #ifdef CONFIG_X86_32
433 	unsigned long		sp0;
434 #endif
435 	unsigned long		sp;
436 #ifdef CONFIG_X86_32
437 	unsigned long		sysenter_cs;
438 #else
439 	unsigned short		es;
440 	unsigned short		ds;
441 	unsigned short		fsindex;
442 	unsigned short		gsindex;
443 #endif
444 
445 #ifdef CONFIG_X86_64
446 	unsigned long		fsbase;
447 	unsigned long		gsbase;
448 #else
449 	/*
450 	 * XXX: this could presumably be unsigned short.  Alternatively,
451 	 * 32-bit kernels could be taught to use fsindex instead.
452 	 */
453 	unsigned long fs;
454 	unsigned long gs;
455 #endif
456 
457 	/* Save middle states of ptrace breakpoints */
458 	struct perf_event	*ptrace_bps[HBP_NUM];
459 	/* Debug status used for traps, single steps, etc... */
460 	unsigned long           virtual_dr6;
461 	/* Keep track of the exact dr7 value set by the user */
462 	unsigned long           ptrace_dr7;
463 	/* Fault info: */
464 	unsigned long		cr2;
465 	unsigned long		trap_nr;
466 	unsigned long		error_code;
467 #ifdef CONFIG_VM86
468 	/* Virtual 86 mode info */
469 	struct vm86		*vm86;
470 #endif
471 	/* IO permissions: */
472 	struct io_bitmap	*io_bitmap;
473 
474 	/*
475 	 * IOPL. Privilege level dependent I/O permission which is
476 	 * emulated via the I/O bitmap to prevent user space from disabling
477 	 * interrupts.
478 	 */
479 	unsigned long		iopl_emul;
480 
481 	unsigned int		iopl_warn:1;
482 	unsigned int		sig_on_uaccess_err:1;
483 
484 	/*
485 	 * Protection Keys Register for Userspace.  Loaded immediately on
486 	 * context switch. Store it in thread_struct to avoid a lookup in
487 	 * the tasks's FPU xstate buffer. This value is only valid when a
488 	 * task is scheduled out. For 'current' the authoritative source of
489 	 * PKRU is the hardware itself.
490 	 */
491 	u32			pkru;
492 
493 #ifdef CONFIG_X86_USER_SHADOW_STACK
494 	unsigned long		features;
495 	unsigned long		features_locked;
496 
497 	struct thread_shstk	shstk;
498 #endif
499 
500 	/* Floating point and extended processor state */
501 	struct fpu		fpu;
502 	/*
503 	 * WARNING: 'fpu' is dynamically-sized.  It *MUST* be at
504 	 * the end.
505 	 */
506 };
507 
508 extern void fpu_thread_struct_whitelist(unsigned long *offset, unsigned long *size);
509 
510 static inline void arch_thread_struct_whitelist(unsigned long *offset,
511 						unsigned long *size)
512 {
513 	fpu_thread_struct_whitelist(offset, size);
514 }
515 
516 static inline void
517 native_load_sp0(unsigned long sp0)
518 {
519 	this_cpu_write(cpu_tss_rw.x86_tss.sp0, sp0);
520 }
521 
522 static __always_inline void native_swapgs(void)
523 {
524 #ifdef CONFIG_X86_64
525 	asm volatile("swapgs" ::: "memory");
526 #endif
527 }
528 
529 static __always_inline unsigned long current_top_of_stack(void)
530 {
531 	/*
532 	 *  We can't read directly from tss.sp0: sp0 on x86_32 is special in
533 	 *  and around vm86 mode and sp0 on x86_64 is special because of the
534 	 *  entry trampoline.
535 	 */
536 	return this_cpu_read_stable(pcpu_hot.top_of_stack);
537 }
538 
539 static __always_inline bool on_thread_stack(void)
540 {
541 	return (unsigned long)(current_top_of_stack() -
542 			       current_stack_pointer) < THREAD_SIZE;
543 }
544 
545 #ifdef CONFIG_PARAVIRT_XXL
546 #include <asm/paravirt.h>
547 #else
548 
549 static inline void load_sp0(unsigned long sp0)
550 {
551 	native_load_sp0(sp0);
552 }
553 
554 #endif /* CONFIG_PARAVIRT_XXL */
555 
556 unsigned long __get_wchan(struct task_struct *p);
557 
558 extern void select_idle_routine(const struct cpuinfo_x86 *c);
559 extern void amd_e400_c1e_apic_setup(void);
560 
561 extern unsigned long		boot_option_idle_override;
562 
563 enum idle_boot_override {IDLE_NO_OVERRIDE=0, IDLE_HALT, IDLE_NOMWAIT,
564 			 IDLE_POLL};
565 
566 extern void enable_sep_cpu(void);
567 
568 
569 /* Defined in head.S */
570 extern struct desc_ptr		early_gdt_descr;
571 
572 extern void switch_gdt_and_percpu_base(int);
573 extern void load_direct_gdt(int);
574 extern void load_fixmap_gdt(int);
575 extern void cpu_init(void);
576 extern void cpu_init_exception_handling(void);
577 extern void cr4_init(void);
578 
579 static inline unsigned long get_debugctlmsr(void)
580 {
581 	unsigned long debugctlmsr = 0;
582 
583 #ifndef CONFIG_X86_DEBUGCTLMSR
584 	if (boot_cpu_data.x86 < 6)
585 		return 0;
586 #endif
587 	rdmsrl(MSR_IA32_DEBUGCTLMSR, debugctlmsr);
588 
589 	return debugctlmsr;
590 }
591 
592 static inline void update_debugctlmsr(unsigned long debugctlmsr)
593 {
594 #ifndef CONFIG_X86_DEBUGCTLMSR
595 	if (boot_cpu_data.x86 < 6)
596 		return;
597 #endif
598 	wrmsrl(MSR_IA32_DEBUGCTLMSR, debugctlmsr);
599 }
600 
601 extern void set_task_blockstep(struct task_struct *task, bool on);
602 
603 /* Boot loader type from the setup header: */
604 extern int			bootloader_type;
605 extern int			bootloader_version;
606 
607 extern char			ignore_fpu_irq;
608 
609 #define HAVE_ARCH_PICK_MMAP_LAYOUT 1
610 #define ARCH_HAS_PREFETCHW
611 
612 #ifdef CONFIG_X86_32
613 # define BASE_PREFETCH		""
614 # define ARCH_HAS_PREFETCH
615 #else
616 # define BASE_PREFETCH		"prefetcht0 %P1"
617 #endif
618 
619 /*
620  * Prefetch instructions for Pentium III (+) and AMD Athlon (+)
621  *
622  * It's not worth to care about 3dnow prefetches for the K6
623  * because they are microcoded there and very slow.
624  */
625 static inline void prefetch(const void *x)
626 {
627 	alternative_input(BASE_PREFETCH, "prefetchnta %P1",
628 			  X86_FEATURE_XMM,
629 			  "m" (*(const char *)x));
630 }
631 
632 /*
633  * 3dnow prefetch to get an exclusive cache line.
634  * Useful for spinlocks to avoid one state transition in the
635  * cache coherency protocol:
636  */
637 static __always_inline void prefetchw(const void *x)
638 {
639 	alternative_input(BASE_PREFETCH, "prefetchw %P1",
640 			  X86_FEATURE_3DNOWPREFETCH,
641 			  "m" (*(const char *)x));
642 }
643 
644 #define TOP_OF_INIT_STACK ((unsigned long)&init_stack + sizeof(init_stack) - \
645 			   TOP_OF_KERNEL_STACK_PADDING)
646 
647 #define task_top_of_stack(task) ((unsigned long)(task_pt_regs(task) + 1))
648 
649 #define task_pt_regs(task) \
650 ({									\
651 	unsigned long __ptr = (unsigned long)task_stack_page(task);	\
652 	__ptr += THREAD_SIZE - TOP_OF_KERNEL_STACK_PADDING;		\
653 	((struct pt_regs *)__ptr) - 1;					\
654 })
655 
656 #ifdef CONFIG_X86_32
657 #define INIT_THREAD  {							  \
658 	.sp0			= TOP_OF_INIT_STACK,			  \
659 	.sysenter_cs		= __KERNEL_CS,				  \
660 }
661 
662 #define KSTK_ESP(task)		(task_pt_regs(task)->sp)
663 
664 #else
665 extern unsigned long __end_init_task[];
666 
667 #define INIT_THREAD {							    \
668 	.sp	= (unsigned long)&__end_init_task - sizeof(struct pt_regs), \
669 }
670 
671 extern unsigned long KSTK_ESP(struct task_struct *task);
672 
673 #endif /* CONFIG_X86_64 */
674 
675 extern void start_thread(struct pt_regs *regs, unsigned long new_ip,
676 					       unsigned long new_sp);
677 
678 /*
679  * This decides where the kernel will search for a free chunk of vm
680  * space during mmap's.
681  */
682 #define __TASK_UNMAPPED_BASE(task_size)	(PAGE_ALIGN(task_size / 3))
683 #define TASK_UNMAPPED_BASE		__TASK_UNMAPPED_BASE(TASK_SIZE_LOW)
684 
685 #define KSTK_EIP(task)		(task_pt_regs(task)->ip)
686 
687 /* Get/set a process' ability to use the timestamp counter instruction */
688 #define GET_TSC_CTL(adr)	get_tsc_mode((adr))
689 #define SET_TSC_CTL(val)	set_tsc_mode((val))
690 
691 extern int get_tsc_mode(unsigned long adr);
692 extern int set_tsc_mode(unsigned int val);
693 
694 DECLARE_PER_CPU(u64, msr_misc_features_shadow);
695 
696 static inline u32 per_cpu_llc_id(unsigned int cpu)
697 {
698 	return per_cpu(cpu_info.topo.llc_id, cpu);
699 }
700 
701 static inline u32 per_cpu_l2c_id(unsigned int cpu)
702 {
703 	return per_cpu(cpu_info.topo.l2c_id, cpu);
704 }
705 
706 #ifdef CONFIG_CPU_SUP_AMD
707 extern u32 amd_get_nodes_per_socket(void);
708 extern u32 amd_get_highest_perf(void);
709 extern void amd_clear_divider(void);
710 extern void amd_check_microcode(void);
711 #else
712 static inline u32 amd_get_nodes_per_socket(void)	{ return 0; }
713 static inline u32 amd_get_highest_perf(void)		{ return 0; }
714 static inline void amd_clear_divider(void)		{ }
715 static inline void amd_check_microcode(void)		{ }
716 #endif
717 
718 extern unsigned long arch_align_stack(unsigned long sp);
719 void free_init_pages(const char *what, unsigned long begin, unsigned long end);
720 extern void free_kernel_image_pages(const char *what, void *begin, void *end);
721 
722 void default_idle(void);
723 #ifdef	CONFIG_XEN
724 bool xen_set_default_idle(void);
725 #else
726 #define xen_set_default_idle 0
727 #endif
728 
729 void __noreturn stop_this_cpu(void *dummy);
730 void microcode_check(struct cpuinfo_x86 *prev_info);
731 void store_cpu_caps(struct cpuinfo_x86 *info);
732 
733 enum l1tf_mitigations {
734 	L1TF_MITIGATION_OFF,
735 	L1TF_MITIGATION_FLUSH_NOWARN,
736 	L1TF_MITIGATION_FLUSH,
737 	L1TF_MITIGATION_FLUSH_NOSMT,
738 	L1TF_MITIGATION_FULL,
739 	L1TF_MITIGATION_FULL_FORCE
740 };
741 
742 extern enum l1tf_mitigations l1tf_mitigation;
743 
744 enum mds_mitigations {
745 	MDS_MITIGATION_OFF,
746 	MDS_MITIGATION_FULL,
747 	MDS_MITIGATION_VMWERV,
748 };
749 
750 extern bool gds_ucode_mitigated(void);
751 
752 /*
753  * Make previous memory operations globally visible before
754  * a WRMSR.
755  *
756  * MFENCE makes writes visible, but only affects load/store
757  * instructions.  WRMSR is unfortunately not a load/store
758  * instruction and is unaffected by MFENCE.  The LFENCE ensures
759  * that the WRMSR is not reordered.
760  *
761  * Most WRMSRs are full serializing instructions themselves and
762  * do not require this barrier.  This is only required for the
763  * IA32_TSC_DEADLINE and X2APIC MSRs.
764  */
765 static inline void weak_wrmsr_fence(void)
766 {
767 	alternative("mfence; lfence", "", ALT_NOT(X86_FEATURE_APIC_MSRS_FENCE));
768 }
769 
770 #endif /* _ASM_X86_PROCESSOR_H */
771