cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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processor.h (21985B)


      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 */
      8struct task_struct;
      9struct mm_struct;
     10struct io_bitmap;
     11struct 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/page.h>
     20#include <asm/pgtable_types.h>
     21#include <asm/percpu.h>
     22#include <asm/msr.h>
     23#include <asm/desc_defs.h>
     24#include <asm/nops.h>
     25#include <asm/special_insns.h>
     26#include <asm/fpu/types.h>
     27#include <asm/unwind_hints.h>
     28#include <asm/vmxfeatures.h>
     29#include <asm/vdso/processor.h>
     30
     31#include <linux/personality.h>
     32#include <linux/cache.h>
     33#include <linux/threads.h>
     34#include <linux/math64.h>
     35#include <linux/err.h>
     36#include <linux/irqflags.h>
     37#include <linux/mem_encrypt.h>
     38
     39/*
     40 * We handle most unaligned accesses in hardware.  On the other hand
     41 * unaligned DMA can be quite expensive on some Nehalem processors.
     42 *
     43 * Based on this we disable the IP header alignment in network drivers.
     44 */
     45#define NET_IP_ALIGN	0
     46
     47#define HBP_NUM 4
     48
     49/*
     50 * These alignment constraints are for performance in the vSMP case,
     51 * but in the task_struct case we must also meet hardware imposed
     52 * alignment requirements of the FPU state:
     53 */
     54#ifdef CONFIG_X86_VSMP
     55# define ARCH_MIN_TASKALIGN		(1 << INTERNODE_CACHE_SHIFT)
     56# define ARCH_MIN_MMSTRUCT_ALIGN	(1 << INTERNODE_CACHE_SHIFT)
     57#else
     58# define ARCH_MIN_TASKALIGN		__alignof__(union fpregs_state)
     59# define ARCH_MIN_MMSTRUCT_ALIGN	0
     60#endif
     61
     62enum tlb_infos {
     63	ENTRIES,
     64	NR_INFO
     65};
     66
     67extern u16 __read_mostly tlb_lli_4k[NR_INFO];
     68extern u16 __read_mostly tlb_lli_2m[NR_INFO];
     69extern u16 __read_mostly tlb_lli_4m[NR_INFO];
     70extern u16 __read_mostly tlb_lld_4k[NR_INFO];
     71extern u16 __read_mostly tlb_lld_2m[NR_INFO];
     72extern u16 __read_mostly tlb_lld_4m[NR_INFO];
     73extern u16 __read_mostly tlb_lld_1g[NR_INFO];
     74
     75/*
     76 *  CPU type and hardware bug flags. Kept separately for each CPU.
     77 *  Members of this structure are referenced in head_32.S, so think twice
     78 *  before touching them. [mj]
     79 */
     80
     81struct cpuinfo_x86 {
     82	__u8			x86;		/* CPU family */
     83	__u8			x86_vendor;	/* CPU vendor */
     84	__u8			x86_model;
     85	__u8			x86_stepping;
     86#ifdef CONFIG_X86_64
     87	/* Number of 4K pages in DTLB/ITLB combined(in pages): */
     88	int			x86_tlbsize;
     89#endif
     90#ifdef CONFIG_X86_VMX_FEATURE_NAMES
     91	__u32			vmx_capability[NVMXINTS];
     92#endif
     93	__u8			x86_virt_bits;
     94	__u8			x86_phys_bits;
     95	/* CPUID returned core id bits: */
     96	__u8			x86_coreid_bits;
     97	__u8			cu_id;
     98	/* Max extended CPUID function supported: */
     99	__u32			extended_cpuid_level;
    100	/* Maximum supported CPUID level, -1=no CPUID: */
    101	int			cpuid_level;
    102	/*
    103	 * Align to size of unsigned long because the x86_capability array
    104	 * is passed to bitops which require the alignment. Use unnamed
    105	 * union to enforce the array is aligned to size of unsigned long.
    106	 */
    107	union {
    108		__u32		x86_capability[NCAPINTS + NBUGINTS];
    109		unsigned long	x86_capability_alignment;
    110	};
    111	char			x86_vendor_id[16];
    112	char			x86_model_id[64];
    113	/* in KB - valid for CPUS which support this call: */
    114	unsigned int		x86_cache_size;
    115	int			x86_cache_alignment;	/* In bytes */
    116	/* Cache QoS architectural values, valid only on the BSP: */
    117	int			x86_cache_max_rmid;	/* max index */
    118	int			x86_cache_occ_scale;	/* scale to bytes */
    119	int			x86_cache_mbm_width_offset;
    120	int			x86_power;
    121	unsigned long		loops_per_jiffy;
    122	/* protected processor identification number */
    123	u64			ppin;
    124	/* cpuid returned max cores value: */
    125	u16			x86_max_cores;
    126	u16			apicid;
    127	u16			initial_apicid;
    128	u16			x86_clflush_size;
    129	/* number of cores as seen by the OS: */
    130	u16			booted_cores;
    131	/* Physical processor id: */
    132	u16			phys_proc_id;
    133	/* Logical processor id: */
    134	u16			logical_proc_id;
    135	/* Core id: */
    136	u16			cpu_core_id;
    137	u16			cpu_die_id;
    138	u16			logical_die_id;
    139	/* Index into per_cpu list: */
    140	u16			cpu_index;
    141	/*  Is SMT active on this core? */
    142	bool			smt_active;
    143	u32			microcode;
    144	/* Address space bits used by the cache internally */
    145	u8			x86_cache_bits;
    146	unsigned		initialized : 1;
    147} __randomize_layout;
    148
    149struct cpuid_regs {
    150	u32 eax, ebx, ecx, edx;
    151};
    152
    153enum cpuid_regs_idx {
    154	CPUID_EAX = 0,
    155	CPUID_EBX,
    156	CPUID_ECX,
    157	CPUID_EDX,
    158};
    159
    160#define X86_VENDOR_INTEL	0
    161#define X86_VENDOR_CYRIX	1
    162#define X86_VENDOR_AMD		2
    163#define X86_VENDOR_UMC		3
    164#define X86_VENDOR_CENTAUR	5
    165#define X86_VENDOR_TRANSMETA	7
    166#define X86_VENDOR_NSC		8
    167#define X86_VENDOR_HYGON	9
    168#define X86_VENDOR_ZHAOXIN	10
    169#define X86_VENDOR_VORTEX	11
    170#define X86_VENDOR_NUM		12
    171
    172#define X86_VENDOR_UNKNOWN	0xff
    173
    174/*
    175 * capabilities of CPUs
    176 */
    177extern struct cpuinfo_x86	boot_cpu_data;
    178extern struct cpuinfo_x86	new_cpu_data;
    179
    180extern __u32			cpu_caps_cleared[NCAPINTS + NBUGINTS];
    181extern __u32			cpu_caps_set[NCAPINTS + NBUGINTS];
    182
    183#ifdef CONFIG_SMP
    184DECLARE_PER_CPU_READ_MOSTLY(struct cpuinfo_x86, cpu_info);
    185#define cpu_data(cpu)		per_cpu(cpu_info, cpu)
    186#else
    187#define cpu_info		boot_cpu_data
    188#define cpu_data(cpu)		boot_cpu_data
    189#endif
    190
    191extern const struct seq_operations cpuinfo_op;
    192
    193#define cache_line_size()	(boot_cpu_data.x86_cache_alignment)
    194
    195extern void cpu_detect(struct cpuinfo_x86 *c);
    196
    197static inline unsigned long long l1tf_pfn_limit(void)
    198{
    199	return BIT_ULL(boot_cpu_data.x86_cache_bits - 1 - PAGE_SHIFT);
    200}
    201
    202extern void early_cpu_init(void);
    203extern void identify_boot_cpu(void);
    204extern void identify_secondary_cpu(struct cpuinfo_x86 *);
    205extern void print_cpu_info(struct cpuinfo_x86 *);
    206void print_cpu_msr(struct cpuinfo_x86 *);
    207
    208#ifdef CONFIG_X86_32
    209extern int have_cpuid_p(void);
    210#else
    211static inline int have_cpuid_p(void)
    212{
    213	return 1;
    214}
    215#endif
    216static inline void native_cpuid(unsigned int *eax, unsigned int *ebx,
    217				unsigned int *ecx, unsigned int *edx)
    218{
    219	/* ecx is often an input as well as an output. */
    220	asm volatile("cpuid"
    221	    : "=a" (*eax),
    222	      "=b" (*ebx),
    223	      "=c" (*ecx),
    224	      "=d" (*edx)
    225	    : "0" (*eax), "2" (*ecx)
    226	    : "memory");
    227}
    228
    229#define native_cpuid_reg(reg)					\
    230static inline unsigned int native_cpuid_##reg(unsigned int op)	\
    231{								\
    232	unsigned int eax = op, ebx, ecx = 0, edx;		\
    233								\
    234	native_cpuid(&eax, &ebx, &ecx, &edx);			\
    235								\
    236	return reg;						\
    237}
    238
    239/*
    240 * Native CPUID functions returning a single datum.
    241 */
    242native_cpuid_reg(eax)
    243native_cpuid_reg(ebx)
    244native_cpuid_reg(ecx)
    245native_cpuid_reg(edx)
    246
    247/*
    248 * Friendlier CR3 helpers.
    249 */
    250static inline unsigned long read_cr3_pa(void)
    251{
    252	return __read_cr3() & CR3_ADDR_MASK;
    253}
    254
    255static inline unsigned long native_read_cr3_pa(void)
    256{
    257	return __native_read_cr3() & CR3_ADDR_MASK;
    258}
    259
    260static inline void load_cr3(pgd_t *pgdir)
    261{
    262	write_cr3(__sme_pa(pgdir));
    263}
    264
    265/*
    266 * Note that while the legacy 'TSS' name comes from 'Task State Segment',
    267 * on modern x86 CPUs the TSS also holds information important to 64-bit mode,
    268 * unrelated to the task-switch mechanism:
    269 */
    270#ifdef CONFIG_X86_32
    271/* This is the TSS defined by the hardware. */
    272struct x86_hw_tss {
    273	unsigned short		back_link, __blh;
    274	unsigned long		sp0;
    275	unsigned short		ss0, __ss0h;
    276	unsigned long		sp1;
    277
    278	/*
    279	 * We don't use ring 1, so ss1 is a convenient scratch space in
    280	 * the same cacheline as sp0.  We use ss1 to cache the value in
    281	 * MSR_IA32_SYSENTER_CS.  When we context switch
    282	 * MSR_IA32_SYSENTER_CS, we first check if the new value being
    283	 * written matches ss1, and, if it's not, then we wrmsr the new
    284	 * value and update ss1.
    285	 *
    286	 * The only reason we context switch MSR_IA32_SYSENTER_CS is
    287	 * that we set it to zero in vm86 tasks to avoid corrupting the
    288	 * stack if we were to go through the sysenter path from vm86
    289	 * mode.
    290	 */
    291	unsigned short		ss1;	/* MSR_IA32_SYSENTER_CS */
    292
    293	unsigned short		__ss1h;
    294	unsigned long		sp2;
    295	unsigned short		ss2, __ss2h;
    296	unsigned long		__cr3;
    297	unsigned long		ip;
    298	unsigned long		flags;
    299	unsigned long		ax;
    300	unsigned long		cx;
    301	unsigned long		dx;
    302	unsigned long		bx;
    303	unsigned long		sp;
    304	unsigned long		bp;
    305	unsigned long		si;
    306	unsigned long		di;
    307	unsigned short		es, __esh;
    308	unsigned short		cs, __csh;
    309	unsigned short		ss, __ssh;
    310	unsigned short		ds, __dsh;
    311	unsigned short		fs, __fsh;
    312	unsigned short		gs, __gsh;
    313	unsigned short		ldt, __ldth;
    314	unsigned short		trace;
    315	unsigned short		io_bitmap_base;
    316
    317} __attribute__((packed));
    318#else
    319struct x86_hw_tss {
    320	u32			reserved1;
    321	u64			sp0;
    322	u64			sp1;
    323
    324	/*
    325	 * Since Linux does not use ring 2, the 'sp2' slot is unused by
    326	 * hardware.  entry_SYSCALL_64 uses it as scratch space to stash
    327	 * the user RSP value.
    328	 */
    329	u64			sp2;
    330
    331	u64			reserved2;
    332	u64			ist[7];
    333	u32			reserved3;
    334	u32			reserved4;
    335	u16			reserved5;
    336	u16			io_bitmap_base;
    337
    338} __attribute__((packed));
    339#endif
    340
    341/*
    342 * IO-bitmap sizes:
    343 */
    344#define IO_BITMAP_BITS			65536
    345#define IO_BITMAP_BYTES			(IO_BITMAP_BITS / BITS_PER_BYTE)
    346#define IO_BITMAP_LONGS			(IO_BITMAP_BYTES / sizeof(long))
    347
    348#define IO_BITMAP_OFFSET_VALID_MAP				\
    349	(offsetof(struct tss_struct, io_bitmap.bitmap) -	\
    350	 offsetof(struct tss_struct, x86_tss))
    351
    352#define IO_BITMAP_OFFSET_VALID_ALL				\
    353	(offsetof(struct tss_struct, io_bitmap.mapall) -	\
    354	 offsetof(struct tss_struct, x86_tss))
    355
    356#ifdef CONFIG_X86_IOPL_IOPERM
    357/*
    358 * sizeof(unsigned long) coming from an extra "long" at the end of the
    359 * iobitmap. The limit is inclusive, i.e. the last valid byte.
    360 */
    361# define __KERNEL_TSS_LIMIT	\
    362	(IO_BITMAP_OFFSET_VALID_ALL + IO_BITMAP_BYTES + \
    363	 sizeof(unsigned long) - 1)
    364#else
    365# define __KERNEL_TSS_LIMIT	\
    366	(offsetof(struct tss_struct, x86_tss) + sizeof(struct x86_hw_tss) - 1)
    367#endif
    368
    369/* Base offset outside of TSS_LIMIT so unpriviledged IO causes #GP */
    370#define IO_BITMAP_OFFSET_INVALID	(__KERNEL_TSS_LIMIT + 1)
    371
    372struct entry_stack {
    373	char	stack[PAGE_SIZE];
    374};
    375
    376struct entry_stack_page {
    377	struct entry_stack stack;
    378} __aligned(PAGE_SIZE);
    379
    380/*
    381 * All IO bitmap related data stored in the TSS:
    382 */
    383struct x86_io_bitmap {
    384	/* The sequence number of the last active bitmap. */
    385	u64			prev_sequence;
    386
    387	/*
    388	 * Store the dirty size of the last io bitmap offender. The next
    389	 * one will have to do the cleanup as the switch out to a non io
    390	 * bitmap user will just set x86_tss.io_bitmap_base to a value
    391	 * outside of the TSS limit. So for sane tasks there is no need to
    392	 * actually touch the io_bitmap at all.
    393	 */
    394	unsigned int		prev_max;
    395
    396	/*
    397	 * The extra 1 is there because the CPU will access an
    398	 * additional byte beyond the end of the IO permission
    399	 * bitmap. The extra byte must be all 1 bits, and must
    400	 * be within the limit.
    401	 */
    402	unsigned long		bitmap[IO_BITMAP_LONGS + 1];
    403
    404	/*
    405	 * Special I/O bitmap to emulate IOPL(3). All bytes zero,
    406	 * except the additional byte at the end.
    407	 */
    408	unsigned long		mapall[IO_BITMAP_LONGS + 1];
    409};
    410
    411struct tss_struct {
    412	/*
    413	 * The fixed hardware portion.  This must not cross a page boundary
    414	 * at risk of violating the SDM's advice and potentially triggering
    415	 * errata.
    416	 */
    417	struct x86_hw_tss	x86_tss;
    418
    419	struct x86_io_bitmap	io_bitmap;
    420} __aligned(PAGE_SIZE);
    421
    422DECLARE_PER_CPU_PAGE_ALIGNED(struct tss_struct, cpu_tss_rw);
    423
    424/* Per CPU interrupt stacks */
    425struct irq_stack {
    426	char		stack[IRQ_STACK_SIZE];
    427} __aligned(IRQ_STACK_SIZE);
    428
    429DECLARE_PER_CPU(unsigned long, cpu_current_top_of_stack);
    430
    431#ifdef CONFIG_X86_64
    432struct fixed_percpu_data {
    433	/*
    434	 * GCC hardcodes the stack canary as %gs:40.  Since the
    435	 * irq_stack is the object at %gs:0, we reserve the bottom
    436	 * 48 bytes of the irq stack for the canary.
    437	 *
    438	 * Once we are willing to require -mstack-protector-guard-symbol=
    439	 * support for x86_64 stackprotector, we can get rid of this.
    440	 */
    441	char		gs_base[40];
    442	unsigned long	stack_canary;
    443};
    444
    445DECLARE_PER_CPU_FIRST(struct fixed_percpu_data, fixed_percpu_data) __visible;
    446DECLARE_INIT_PER_CPU(fixed_percpu_data);
    447
    448static inline unsigned long cpu_kernelmode_gs_base(int cpu)
    449{
    450	return (unsigned long)per_cpu(fixed_percpu_data.gs_base, cpu);
    451}
    452
    453DECLARE_PER_CPU(void *, hardirq_stack_ptr);
    454DECLARE_PER_CPU(bool, hardirq_stack_inuse);
    455extern asmlinkage void ignore_sysret(void);
    456
    457/* Save actual FS/GS selectors and bases to current->thread */
    458void current_save_fsgs(void);
    459#else	/* X86_64 */
    460#ifdef CONFIG_STACKPROTECTOR
    461DECLARE_PER_CPU(unsigned long, __stack_chk_guard);
    462#endif
    463DECLARE_PER_CPU(struct irq_stack *, hardirq_stack_ptr);
    464DECLARE_PER_CPU(struct irq_stack *, softirq_stack_ptr);
    465#endif	/* !X86_64 */
    466
    467struct perf_event;
    468
    469struct thread_struct {
    470	/* Cached TLS descriptors: */
    471	struct desc_struct	tls_array[GDT_ENTRY_TLS_ENTRIES];
    472#ifdef CONFIG_X86_32
    473	unsigned long		sp0;
    474#endif
    475	unsigned long		sp;
    476#ifdef CONFIG_X86_32
    477	unsigned long		sysenter_cs;
    478#else
    479	unsigned short		es;
    480	unsigned short		ds;
    481	unsigned short		fsindex;
    482	unsigned short		gsindex;
    483#endif
    484
    485#ifdef CONFIG_X86_64
    486	unsigned long		fsbase;
    487	unsigned long		gsbase;
    488#else
    489	/*
    490	 * XXX: this could presumably be unsigned short.  Alternatively,
    491	 * 32-bit kernels could be taught to use fsindex instead.
    492	 */
    493	unsigned long fs;
    494	unsigned long gs;
    495#endif
    496
    497	/* Save middle states of ptrace breakpoints */
    498	struct perf_event	*ptrace_bps[HBP_NUM];
    499	/* Debug status used for traps, single steps, etc... */
    500	unsigned long           virtual_dr6;
    501	/* Keep track of the exact dr7 value set by the user */
    502	unsigned long           ptrace_dr7;
    503	/* Fault info: */
    504	unsigned long		cr2;
    505	unsigned long		trap_nr;
    506	unsigned long		error_code;
    507#ifdef CONFIG_VM86
    508	/* Virtual 86 mode info */
    509	struct vm86		*vm86;
    510#endif
    511	/* IO permissions: */
    512	struct io_bitmap	*io_bitmap;
    513
    514	/*
    515	 * IOPL. Privilege level dependent I/O permission which is
    516	 * emulated via the I/O bitmap to prevent user space from disabling
    517	 * interrupts.
    518	 */
    519	unsigned long		iopl_emul;
    520
    521	unsigned int		iopl_warn:1;
    522	unsigned int		sig_on_uaccess_err:1;
    523
    524	/*
    525	 * Protection Keys Register for Userspace.  Loaded immediately on
    526	 * context switch. Store it in thread_struct to avoid a lookup in
    527	 * the tasks's FPU xstate buffer. This value is only valid when a
    528	 * task is scheduled out. For 'current' the authoritative source of
    529	 * PKRU is the hardware itself.
    530	 */
    531	u32			pkru;
    532
    533	/* Floating point and extended processor state */
    534	struct fpu		fpu;
    535	/*
    536	 * WARNING: 'fpu' is dynamically-sized.  It *MUST* be at
    537	 * the end.
    538	 */
    539};
    540
    541extern void fpu_thread_struct_whitelist(unsigned long *offset, unsigned long *size);
    542
    543static inline void arch_thread_struct_whitelist(unsigned long *offset,
    544						unsigned long *size)
    545{
    546	fpu_thread_struct_whitelist(offset, size);
    547}
    548
    549static inline void
    550native_load_sp0(unsigned long sp0)
    551{
    552	this_cpu_write(cpu_tss_rw.x86_tss.sp0, sp0);
    553}
    554
    555static __always_inline void native_swapgs(void)
    556{
    557#ifdef CONFIG_X86_64
    558	asm volatile("swapgs" ::: "memory");
    559#endif
    560}
    561
    562static __always_inline unsigned long current_top_of_stack(void)
    563{
    564	/*
    565	 *  We can't read directly from tss.sp0: sp0 on x86_32 is special in
    566	 *  and around vm86 mode and sp0 on x86_64 is special because of the
    567	 *  entry trampoline.
    568	 */
    569	return this_cpu_read_stable(cpu_current_top_of_stack);
    570}
    571
    572static __always_inline bool on_thread_stack(void)
    573{
    574	return (unsigned long)(current_top_of_stack() -
    575			       current_stack_pointer) < THREAD_SIZE;
    576}
    577
    578#ifdef CONFIG_PARAVIRT_XXL
    579#include <asm/paravirt.h>
    580#else
    581#define __cpuid			native_cpuid
    582
    583static inline void load_sp0(unsigned long sp0)
    584{
    585	native_load_sp0(sp0);
    586}
    587
    588#endif /* CONFIG_PARAVIRT_XXL */
    589
    590/* Free all resources held by a thread. */
    591extern void release_thread(struct task_struct *);
    592
    593unsigned long __get_wchan(struct task_struct *p);
    594
    595/*
    596 * Generic CPUID function
    597 * clear %ecx since some cpus (Cyrix MII) do not set or clear %ecx
    598 * resulting in stale register contents being returned.
    599 */
    600static inline void cpuid(unsigned int op,
    601			 unsigned int *eax, unsigned int *ebx,
    602			 unsigned int *ecx, unsigned int *edx)
    603{
    604	*eax = op;
    605	*ecx = 0;
    606	__cpuid(eax, ebx, ecx, edx);
    607}
    608
    609/* Some CPUID calls want 'count' to be placed in ecx */
    610static inline void cpuid_count(unsigned int op, int count,
    611			       unsigned int *eax, unsigned int *ebx,
    612			       unsigned int *ecx, unsigned int *edx)
    613{
    614	*eax = op;
    615	*ecx = count;
    616	__cpuid(eax, ebx, ecx, edx);
    617}
    618
    619/*
    620 * CPUID functions returning a single datum
    621 */
    622static inline unsigned int cpuid_eax(unsigned int op)
    623{
    624	unsigned int eax, ebx, ecx, edx;
    625
    626	cpuid(op, &eax, &ebx, &ecx, &edx);
    627
    628	return eax;
    629}
    630
    631static inline unsigned int cpuid_ebx(unsigned int op)
    632{
    633	unsigned int eax, ebx, ecx, edx;
    634
    635	cpuid(op, &eax, &ebx, &ecx, &edx);
    636
    637	return ebx;
    638}
    639
    640static inline unsigned int cpuid_ecx(unsigned int op)
    641{
    642	unsigned int eax, ebx, ecx, edx;
    643
    644	cpuid(op, &eax, &ebx, &ecx, &edx);
    645
    646	return ecx;
    647}
    648
    649static inline unsigned int cpuid_edx(unsigned int op)
    650{
    651	unsigned int eax, ebx, ecx, edx;
    652
    653	cpuid(op, &eax, &ebx, &ecx, &edx);
    654
    655	return edx;
    656}
    657
    658extern void select_idle_routine(const struct cpuinfo_x86 *c);
    659extern void amd_e400_c1e_apic_setup(void);
    660
    661extern unsigned long		boot_option_idle_override;
    662
    663enum idle_boot_override {IDLE_NO_OVERRIDE=0, IDLE_HALT, IDLE_NOMWAIT,
    664			 IDLE_POLL};
    665
    666extern void enable_sep_cpu(void);
    667extern int sysenter_setup(void);
    668
    669
    670/* Defined in head.S */
    671extern struct desc_ptr		early_gdt_descr;
    672
    673extern void switch_to_new_gdt(int);
    674extern void load_direct_gdt(int);
    675extern void load_fixmap_gdt(int);
    676extern void load_percpu_segment(int);
    677extern void cpu_init(void);
    678extern void cpu_init_secondary(void);
    679extern void cpu_init_exception_handling(void);
    680extern void cr4_init(void);
    681
    682static inline unsigned long get_debugctlmsr(void)
    683{
    684	unsigned long debugctlmsr = 0;
    685
    686#ifndef CONFIG_X86_DEBUGCTLMSR
    687	if (boot_cpu_data.x86 < 6)
    688		return 0;
    689#endif
    690	rdmsrl(MSR_IA32_DEBUGCTLMSR, debugctlmsr);
    691
    692	return debugctlmsr;
    693}
    694
    695static inline void update_debugctlmsr(unsigned long debugctlmsr)
    696{
    697#ifndef CONFIG_X86_DEBUGCTLMSR
    698	if (boot_cpu_data.x86 < 6)
    699		return;
    700#endif
    701	wrmsrl(MSR_IA32_DEBUGCTLMSR, debugctlmsr);
    702}
    703
    704extern void set_task_blockstep(struct task_struct *task, bool on);
    705
    706/* Boot loader type from the setup header: */
    707extern int			bootloader_type;
    708extern int			bootloader_version;
    709
    710extern char			ignore_fpu_irq;
    711
    712#define HAVE_ARCH_PICK_MMAP_LAYOUT 1
    713#define ARCH_HAS_PREFETCHW
    714#define ARCH_HAS_SPINLOCK_PREFETCH
    715
    716#ifdef CONFIG_X86_32
    717# define BASE_PREFETCH		""
    718# define ARCH_HAS_PREFETCH
    719#else
    720# define BASE_PREFETCH		"prefetcht0 %P1"
    721#endif
    722
    723/*
    724 * Prefetch instructions for Pentium III (+) and AMD Athlon (+)
    725 *
    726 * It's not worth to care about 3dnow prefetches for the K6
    727 * because they are microcoded there and very slow.
    728 */
    729static inline void prefetch(const void *x)
    730{
    731	alternative_input(BASE_PREFETCH, "prefetchnta %P1",
    732			  X86_FEATURE_XMM,
    733			  "m" (*(const char *)x));
    734}
    735
    736/*
    737 * 3dnow prefetch to get an exclusive cache line.
    738 * Useful for spinlocks to avoid one state transition in the
    739 * cache coherency protocol:
    740 */
    741static __always_inline void prefetchw(const void *x)
    742{
    743	alternative_input(BASE_PREFETCH, "prefetchw %P1",
    744			  X86_FEATURE_3DNOWPREFETCH,
    745			  "m" (*(const char *)x));
    746}
    747
    748static inline void spin_lock_prefetch(const void *x)
    749{
    750	prefetchw(x);
    751}
    752
    753#define TOP_OF_INIT_STACK ((unsigned long)&init_stack + sizeof(init_stack) - \
    754			   TOP_OF_KERNEL_STACK_PADDING)
    755
    756#define task_top_of_stack(task) ((unsigned long)(task_pt_regs(task) + 1))
    757
    758#define task_pt_regs(task) \
    759({									\
    760	unsigned long __ptr = (unsigned long)task_stack_page(task);	\
    761	__ptr += THREAD_SIZE - TOP_OF_KERNEL_STACK_PADDING;		\
    762	((struct pt_regs *)__ptr) - 1;					\
    763})
    764
    765#ifdef CONFIG_X86_32
    766#define INIT_THREAD  {							  \
    767	.sp0			= TOP_OF_INIT_STACK,			  \
    768	.sysenter_cs		= __KERNEL_CS,				  \
    769}
    770
    771#define KSTK_ESP(task)		(task_pt_regs(task)->sp)
    772
    773#else
    774#define INIT_THREAD { }
    775
    776extern unsigned long KSTK_ESP(struct task_struct *task);
    777
    778#endif /* CONFIG_X86_64 */
    779
    780extern void start_thread(struct pt_regs *regs, unsigned long new_ip,
    781					       unsigned long new_sp);
    782
    783/*
    784 * This decides where the kernel will search for a free chunk of vm
    785 * space during mmap's.
    786 */
    787#define __TASK_UNMAPPED_BASE(task_size)	(PAGE_ALIGN(task_size / 3))
    788#define TASK_UNMAPPED_BASE		__TASK_UNMAPPED_BASE(TASK_SIZE_LOW)
    789
    790#define KSTK_EIP(task)		(task_pt_regs(task)->ip)
    791
    792/* Get/set a process' ability to use the timestamp counter instruction */
    793#define GET_TSC_CTL(adr)	get_tsc_mode((adr))
    794#define SET_TSC_CTL(val)	set_tsc_mode((val))
    795
    796extern int get_tsc_mode(unsigned long adr);
    797extern int set_tsc_mode(unsigned int val);
    798
    799DECLARE_PER_CPU(u64, msr_misc_features_shadow);
    800
    801extern u16 get_llc_id(unsigned int cpu);
    802
    803#ifdef CONFIG_CPU_SUP_AMD
    804extern u32 amd_get_nodes_per_socket(void);
    805extern u32 amd_get_highest_perf(void);
    806#else
    807static inline u32 amd_get_nodes_per_socket(void)	{ return 0; }
    808static inline u32 amd_get_highest_perf(void)		{ return 0; }
    809#endif
    810
    811#define for_each_possible_hypervisor_cpuid_base(function) \
    812	for (function = 0x40000000; function < 0x40010000; function += 0x100)
    813
    814static inline uint32_t hypervisor_cpuid_base(const char *sig, uint32_t leaves)
    815{
    816	uint32_t base, eax, signature[3];
    817
    818	for_each_possible_hypervisor_cpuid_base(base) {
    819		cpuid(base, &eax, &signature[0], &signature[1], &signature[2]);
    820
    821		if (!memcmp(sig, signature, 12) &&
    822		    (leaves == 0 || ((eax - base) >= leaves)))
    823			return base;
    824	}
    825
    826	return 0;
    827}
    828
    829extern unsigned long arch_align_stack(unsigned long sp);
    830void free_init_pages(const char *what, unsigned long begin, unsigned long end);
    831extern void free_kernel_image_pages(const char *what, void *begin, void *end);
    832
    833void default_idle(void);
    834#ifdef	CONFIG_XEN
    835bool xen_set_default_idle(void);
    836#else
    837#define xen_set_default_idle 0
    838#endif
    839
    840void __noreturn stop_this_cpu(void *dummy);
    841void microcode_check(void);
    842
    843enum l1tf_mitigations {
    844	L1TF_MITIGATION_OFF,
    845	L1TF_MITIGATION_FLUSH_NOWARN,
    846	L1TF_MITIGATION_FLUSH,
    847	L1TF_MITIGATION_FLUSH_NOSMT,
    848	L1TF_MITIGATION_FULL,
    849	L1TF_MITIGATION_FULL_FORCE
    850};
    851
    852extern enum l1tf_mitigations l1tf_mitigation;
    853
    854enum mds_mitigations {
    855	MDS_MITIGATION_OFF,
    856	MDS_MITIGATION_FULL,
    857	MDS_MITIGATION_VMWERV,
    858};
    859
    860#ifdef CONFIG_X86_SGX
    861int arch_memory_failure(unsigned long pfn, int flags);
    862#define arch_memory_failure arch_memory_failure
    863
    864bool arch_is_platform_page(u64 paddr);
    865#define arch_is_platform_page arch_is_platform_page
    866#endif
    867
    868#endif /* _ASM_X86_PROCESSOR_H */