1 #ifndef _ASM_X86_PROCESSOR_H
2 #define _ASM_X86_PROCESSOR_H
4 #include <asm/processor-flags.h>
6 /* Forward declaration, a strange C thing */
11 #include <asm/math_emu.h>
12 #include <asm/segment.h>
13 #include <asm/types.h>
14 #include <uapi/asm/sigcontext.h>
15 #include <asm/current.h>
16 #include <asm/cpufeatures.h>
18 #include <asm/pgtable_types.h>
19 #include <asm/percpu.h>
21 #include <asm/desc_defs.h>
23 #include <asm/special_insns.h>
24 #include <asm/fpu/types.h>
26 #include <linux/personality.h>
27 #include <linux/cache.h>
28 #include <linux/threads.h>
29 #include <linux/math64.h>
30 #include <linux/err.h>
31 #include <linux/irqflags.h>
34 * We handle most unaligned accesses in hardware. On the other hand
35 * unaligned DMA can be quite expensive on some Nehalem processors.
37 * Based on this we disable the IP header alignment in network drivers.
39 #define NET_IP_ALIGN 0
43 * Default implementation of macro that returns current
44 * instruction pointer ("program counter").
46 static inline void *current_text_addr(void)
50 asm volatile("mov $1f, %0; 1:":"=r" (pc));
56 * These alignment constraints are for performance in the vSMP case,
57 * but in the task_struct case we must also meet hardware imposed
58 * alignment requirements of the FPU state:
60 #ifdef CONFIG_X86_VSMP
61 # define ARCH_MIN_TASKALIGN (1 << INTERNODE_CACHE_SHIFT)
62 # define ARCH_MIN_MMSTRUCT_ALIGN (1 << INTERNODE_CACHE_SHIFT)
64 # define ARCH_MIN_TASKALIGN __alignof__(union fpregs_state)
65 # define ARCH_MIN_MMSTRUCT_ALIGN 0
73 extern u16 __read_mostly tlb_lli_4k[NR_INFO];
74 extern u16 __read_mostly tlb_lli_2m[NR_INFO];
75 extern u16 __read_mostly tlb_lli_4m[NR_INFO];
76 extern u16 __read_mostly tlb_lld_4k[NR_INFO];
77 extern u16 __read_mostly tlb_lld_2m[NR_INFO];
78 extern u16 __read_mostly tlb_lld_4m[NR_INFO];
79 extern u16 __read_mostly tlb_lld_1g[NR_INFO];
82 * CPU type and hardware bug flags. Kept separately for each CPU.
83 * Members of this structure are referenced in head.S, so think twice
84 * before touching them. [mj]
88 __u8 x86; /* CPU family */
89 __u8 x86_vendor; /* CPU vendor */
93 char wp_works_ok; /* It doesn't on 386's */
95 /* Problems on some 486Dx4's and old 386's: */
100 /* Number of 4K pages in DTLB/ITLB combined(in pages): */
105 /* CPUID returned core id bits: */
106 __u8 x86_coreid_bits;
108 /* Max extended CPUID function supported: */
109 __u32 extended_cpuid_level;
110 /* Maximum supported CPUID level, -1=no CPUID: */
112 __u32 x86_capability[NCAPINTS + NBUGINTS];
113 char x86_vendor_id[16];
114 char x86_model_id[64];
115 /* in KB - valid for CPUS which support this call: */
117 int x86_cache_alignment; /* In bytes */
118 /* Cache QoS architectural values: */
119 int x86_cache_max_rmid; /* max index */
120 int x86_cache_occ_scale; /* scale to bytes */
122 unsigned long loops_per_jiffy;
123 /* cpuid returned max cores value: */
127 u16 x86_clflush_size;
128 /* number of cores as seen by the OS: */
130 /* Physical processor id: */
132 /* Logical processor id: */
136 /* Index into per_cpu list: */
142 u32 eax, ebx, ecx, edx;
145 enum cpuid_regs_idx {
152 #define X86_VENDOR_INTEL 0
153 #define X86_VENDOR_CYRIX 1
154 #define X86_VENDOR_AMD 2
155 #define X86_VENDOR_UMC 3
156 #define X86_VENDOR_CENTAUR 5
157 #define X86_VENDOR_TRANSMETA 7
158 #define X86_VENDOR_NSC 8
159 #define X86_VENDOR_NUM 9
161 #define X86_VENDOR_UNKNOWN 0xff
164 * capabilities of CPUs
166 extern struct cpuinfo_x86 boot_cpu_data;
167 extern struct cpuinfo_x86 new_cpu_data;
169 extern struct tss_struct doublefault_tss;
170 extern __u32 cpu_caps_cleared[NCAPINTS];
171 extern __u32 cpu_caps_set[NCAPINTS];
174 DECLARE_PER_CPU_READ_MOSTLY(struct cpuinfo_x86, cpu_info);
175 #define cpu_data(cpu) per_cpu(cpu_info, cpu)
177 #define cpu_info boot_cpu_data
178 #define cpu_data(cpu) boot_cpu_data
181 extern const struct seq_operations cpuinfo_op;
183 #define cache_line_size() (boot_cpu_data.x86_cache_alignment)
185 extern void cpu_detect(struct cpuinfo_x86 *c);
187 extern void early_cpu_init(void);
188 extern void identify_boot_cpu(void);
189 extern void identify_secondary_cpu(struct cpuinfo_x86 *);
190 extern void print_cpu_info(struct cpuinfo_x86 *);
191 void print_cpu_msr(struct cpuinfo_x86 *);
192 extern void init_scattered_cpuid_features(struct cpuinfo_x86 *c);
193 extern u32 get_scattered_cpuid_leaf(unsigned int level,
194 unsigned int sub_leaf,
195 enum cpuid_regs_idx reg);
196 extern unsigned int init_intel_cacheinfo(struct cpuinfo_x86 *c);
197 extern void init_amd_cacheinfo(struct cpuinfo_x86 *c);
199 extern void detect_extended_topology(struct cpuinfo_x86 *c);
200 extern void detect_ht(struct cpuinfo_x86 *c);
203 extern int have_cpuid_p(void);
205 static inline int have_cpuid_p(void)
210 static inline void native_cpuid(unsigned int *eax, unsigned int *ebx,
211 unsigned int *ecx, unsigned int *edx)
213 /* ecx is often an input as well as an output. */
219 : "0" (*eax), "2" (*ecx)
223 #define native_cpuid_reg(reg) \
224 static inline unsigned int native_cpuid_##reg(unsigned int op) \
226 unsigned int eax = op, ebx, ecx = 0, edx; \
228 native_cpuid(&eax, &ebx, &ecx, &edx); \
234 * Native CPUID functions returning a single datum.
236 native_cpuid_reg(eax)
237 native_cpuid_reg(ebx)
238 native_cpuid_reg(ecx)
239 native_cpuid_reg(edx)
241 static inline void load_cr3(pgd_t *pgdir)
243 write_cr3(__pa(pgdir));
247 /* This is the TSS defined by the hardware. */
249 unsigned short back_link, __blh;
251 unsigned short ss0, __ss0h;
255 * We don't use ring 1, so ss1 is a convenient scratch space in
256 * the same cacheline as sp0. We use ss1 to cache the value in
257 * MSR_IA32_SYSENTER_CS. When we context switch
258 * MSR_IA32_SYSENTER_CS, we first check if the new value being
259 * written matches ss1, and, if it's not, then we wrmsr the new
260 * value and update ss1.
262 * The only reason we context switch MSR_IA32_SYSENTER_CS is
263 * that we set it to zero in vm86 tasks to avoid corrupting the
264 * stack if we were to go through the sysenter path from vm86
267 unsigned short ss1; /* MSR_IA32_SYSENTER_CS */
269 unsigned short __ss1h;
271 unsigned short ss2, __ss2h;
283 unsigned short es, __esh;
284 unsigned short cs, __csh;
285 unsigned short ss, __ssh;
286 unsigned short ds, __dsh;
287 unsigned short fs, __fsh;
288 unsigned short gs, __gsh;
289 unsigned short ldt, __ldth;
290 unsigned short trace;
291 unsigned short io_bitmap_base;
293 } __attribute__((packed));
307 } __attribute__((packed)) ____cacheline_aligned;
313 #define IO_BITMAP_BITS 65536
314 #define IO_BITMAP_BYTES (IO_BITMAP_BITS/8)
315 #define IO_BITMAP_LONGS (IO_BITMAP_BYTES/sizeof(long))
316 #define IO_BITMAP_OFFSET offsetof(struct tss_struct, io_bitmap)
317 #define INVALID_IO_BITMAP_OFFSET 0x8000
321 * The hardware state:
323 struct x86_hw_tss x86_tss;
326 * The extra 1 is there because the CPU will access an
327 * additional byte beyond the end of the IO permission
328 * bitmap. The extra byte must be all 1 bits, and must
329 * be within the limit.
331 unsigned long io_bitmap[IO_BITMAP_LONGS + 1];
335 * Space for the temporary SYSENTER stack.
337 unsigned long SYSENTER_stack_canary;
338 unsigned long SYSENTER_stack[64];
341 } ____cacheline_aligned;
343 DECLARE_PER_CPU_SHARED_ALIGNED(struct tss_struct, cpu_tss);
346 DECLARE_PER_CPU(unsigned long, cpu_current_top_of_stack);
350 * Save the original ist values for checking stack pointers during debugging
353 unsigned long ist[7];
357 DECLARE_PER_CPU(struct orig_ist, orig_ist);
359 union irq_stack_union {
360 char irq_stack[IRQ_STACK_SIZE];
362 * GCC hardcodes the stack canary as %gs:40. Since the
363 * irq_stack is the object at %gs:0, we reserve the bottom
364 * 48 bytes of the irq stack for the canary.
368 unsigned long stack_canary;
372 DECLARE_PER_CPU_FIRST(union irq_stack_union, irq_stack_union) __visible;
373 DECLARE_INIT_PER_CPU(irq_stack_union);
375 DECLARE_PER_CPU(char *, irq_stack_ptr);
376 DECLARE_PER_CPU(unsigned int, irq_count);
377 extern asmlinkage void ignore_sysret(void);
379 #ifdef CONFIG_CC_STACKPROTECTOR
381 * Make sure stack canary segment base is cached-aligned:
382 * "For Intel Atom processors, avoid non zero segment base address
383 * that is not aligned to cache line boundary at all cost."
384 * (Optim Ref Manual Assembly/Compiler Coding Rule 15.)
386 struct stack_canary {
387 char __pad[20]; /* canary at %gs:20 */
388 unsigned long canary;
390 DECLARE_PER_CPU_ALIGNED(struct stack_canary, stack_canary);
393 * per-CPU IRQ handling stacks
396 u32 stack[THREAD_SIZE/sizeof(u32)];
397 } __aligned(THREAD_SIZE);
399 DECLARE_PER_CPU(struct irq_stack *, hardirq_stack);
400 DECLARE_PER_CPU(struct irq_stack *, softirq_stack);
403 extern unsigned int fpu_kernel_xstate_size;
404 extern unsigned int fpu_user_xstate_size;
412 struct thread_struct {
413 /* Cached TLS descriptors: */
414 struct desc_struct tls_array[GDT_ENTRY_TLS_ENTRIES];
418 unsigned long sysenter_cs;
422 unsigned short fsindex;
423 unsigned short gsindex;
426 u32 status; /* thread synchronous flags */
429 unsigned long fsbase;
430 unsigned long gsbase;
433 * XXX: this could presumably be unsigned short. Alternatively,
434 * 32-bit kernels could be taught to use fsindex instead.
440 /* Save middle states of ptrace breakpoints */
441 struct perf_event *ptrace_bps[HBP_NUM];
442 /* Debug status used for traps, single steps, etc... */
443 unsigned long debugreg6;
444 /* Keep track of the exact dr7 value set by the user */
445 unsigned long ptrace_dr7;
448 unsigned long trap_nr;
449 unsigned long error_code;
451 /* Virtual 86 mode info */
454 /* IO permissions: */
455 unsigned long *io_bitmap_ptr;
457 /* Max allowed port in the bitmap, in bytes: */
458 unsigned io_bitmap_max;
460 mm_segment_t addr_limit;
462 unsigned int sig_on_uaccess_err:1;
463 unsigned int uaccess_err:1; /* uaccess failed */
465 /* Floating point and extended processor state */
468 * WARNING: 'fpu' is dynamically-sized. It *MUST* be at
474 * Thread-synchronous status.
476 * This is different from the flags in that nobody else
477 * ever touches our thread-synchronous status, so we don't
478 * have to worry about atomic accesses.
480 #define TS_COMPAT 0x0002 /* 32bit syscall active (64BIT)*/
483 * Set IOPL bits in EFLAGS from given mask
485 static inline void native_set_iopl_mask(unsigned mask)
490 asm volatile ("pushfl;"
497 : "i" (~X86_EFLAGS_IOPL), "r" (mask));
502 native_load_sp0(struct tss_struct *tss, struct thread_struct *thread)
504 tss->x86_tss.sp0 = thread->sp0;
506 /* Only happens when SEP is enabled, no need to test "SEP"arately: */
507 if (unlikely(tss->x86_tss.ss1 != thread->sysenter_cs)) {
508 tss->x86_tss.ss1 = thread->sysenter_cs;
509 wrmsr(MSR_IA32_SYSENTER_CS, thread->sysenter_cs, 0);
514 static inline void native_swapgs(void)
517 asm volatile("swapgs" ::: "memory");
521 static inline unsigned long current_top_of_stack(void)
524 return this_cpu_read_stable(cpu_tss.x86_tss.sp0);
526 /* sp0 on x86_32 is special in and around vm86 mode. */
527 return this_cpu_read_stable(cpu_current_top_of_stack);
531 #ifdef CONFIG_PARAVIRT
532 #include <asm/paravirt.h>
534 #define __cpuid native_cpuid
536 static inline void load_sp0(struct tss_struct *tss,
537 struct thread_struct *thread)
539 native_load_sp0(tss, thread);
542 #define set_iopl_mask native_set_iopl_mask
543 #endif /* CONFIG_PARAVIRT */
545 /* Free all resources held by a thread. */
546 extern void release_thread(struct task_struct *);
548 unsigned long get_wchan(struct task_struct *p);
551 * Generic CPUID function
552 * clear %ecx since some cpus (Cyrix MII) do not set or clear %ecx
553 * resulting in stale register contents being returned.
555 static inline void cpuid(unsigned int op,
556 unsigned int *eax, unsigned int *ebx,
557 unsigned int *ecx, unsigned int *edx)
561 __cpuid(eax, ebx, ecx, edx);
564 /* Some CPUID calls want 'count' to be placed in ecx */
565 static inline void cpuid_count(unsigned int op, int count,
566 unsigned int *eax, unsigned int *ebx,
567 unsigned int *ecx, unsigned int *edx)
571 __cpuid(eax, ebx, ecx, edx);
575 * CPUID functions returning a single datum
577 static inline unsigned int cpuid_eax(unsigned int op)
579 unsigned int eax, ebx, ecx, edx;
581 cpuid(op, &eax, &ebx, &ecx, &edx);
586 static inline unsigned int cpuid_ebx(unsigned int op)
588 unsigned int eax, ebx, ecx, edx;
590 cpuid(op, &eax, &ebx, &ecx, &edx);
595 static inline unsigned int cpuid_ecx(unsigned int op)
597 unsigned int eax, ebx, ecx, edx;
599 cpuid(op, &eax, &ebx, &ecx, &edx);
604 static inline unsigned int cpuid_edx(unsigned int op)
606 unsigned int eax, ebx, ecx, edx;
608 cpuid(op, &eax, &ebx, &ecx, &edx);
613 /* REP NOP (PAUSE) is a good thing to insert into busy-wait loops. */
614 static __always_inline void rep_nop(void)
616 asm volatile("rep; nop" ::: "memory");
619 static __always_inline void cpu_relax(void)
625 * This function forces the icache and prefetched instruction stream to
626 * catch up with reality in two very specific cases:
628 * a) Text was modified using one virtual address and is about to be executed
629 * from the same physical page at a different virtual address.
631 * b) Text was modified on a different CPU, may subsequently be
632 * executed on this CPU, and you want to make sure the new version
633 * gets executed. This generally means you're calling this in a IPI.
635 * If you're calling this for a different reason, you're probably doing
638 static inline void sync_core(void)
641 * There are quite a few ways to do this. IRET-to-self is nice
642 * because it works on every CPU, at any CPL (so it's compatible
643 * with paravirtualization), and it never exits to a hypervisor.
644 * The only down sides are that it's a bit slow (it seems to be
645 * a bit more than 2x slower than the fastest options) and that
646 * it unmasks NMIs. The "push %cs" is needed because, in
647 * paravirtual environments, __KERNEL_CS may not be a valid CS
648 * value when we do IRET directly.
650 * In case NMI unmasking or performance ever becomes a problem,
651 * the next best option appears to be MOV-to-CR2 and an
652 * unconditional jump. That sequence also works on all CPUs,
653 * but it will fault at CPL3 (i.e. Xen PV and lguest).
655 * CPUID is the conventional way, but it's nasty: it doesn't
656 * exist on some 486-like CPUs, and it usually exits to a
659 * Like all of Linux's memory ordering operations, this is a
660 * compiler barrier as well.
662 register void *__sp asm(_ASM_SP);
671 : "+r" (__sp) : : "memory");
679 "addq $8, (%%rsp)\n\t"
686 : "=&r" (tmp), "+r" (__sp) : : "cc", "memory");
690 extern void select_idle_routine(const struct cpuinfo_x86 *c);
691 extern void amd_e400_c1e_apic_setup(void);
693 extern unsigned long boot_option_idle_override;
695 enum idle_boot_override {IDLE_NO_OVERRIDE=0, IDLE_HALT, IDLE_NOMWAIT,
698 extern void enable_sep_cpu(void);
699 extern int sysenter_setup(void);
701 extern void early_trap_init(void);
702 void early_trap_pf_init(void);
704 /* Defined in head.S */
705 extern struct desc_ptr early_gdt_descr;
707 extern void cpu_set_gdt(int);
708 extern void switch_to_new_gdt(int);
709 extern void load_percpu_segment(int);
710 extern void cpu_init(void);
712 static inline unsigned long get_debugctlmsr(void)
714 unsigned long debugctlmsr = 0;
716 #ifndef CONFIG_X86_DEBUGCTLMSR
717 if (boot_cpu_data.x86 < 6)
720 rdmsrl(MSR_IA32_DEBUGCTLMSR, debugctlmsr);
725 static inline void update_debugctlmsr(unsigned long debugctlmsr)
727 #ifndef CONFIG_X86_DEBUGCTLMSR
728 if (boot_cpu_data.x86 < 6)
731 wrmsrl(MSR_IA32_DEBUGCTLMSR, debugctlmsr);
734 extern void set_task_blockstep(struct task_struct *task, bool on);
736 /* Boot loader type from the setup header: */
737 extern int bootloader_type;
738 extern int bootloader_version;
740 extern char ignore_fpu_irq;
742 #define HAVE_ARCH_PICK_MMAP_LAYOUT 1
743 #define ARCH_HAS_PREFETCHW
744 #define ARCH_HAS_SPINLOCK_PREFETCH
747 # define BASE_PREFETCH ""
748 # define ARCH_HAS_PREFETCH
750 # define BASE_PREFETCH "prefetcht0 %P1"
754 * Prefetch instructions for Pentium III (+) and AMD Athlon (+)
756 * It's not worth to care about 3dnow prefetches for the K6
757 * because they are microcoded there and very slow.
759 static inline void prefetch(const void *x)
761 alternative_input(BASE_PREFETCH, "prefetchnta %P1",
763 "m" (*(const char *)x));
767 * 3dnow prefetch to get an exclusive cache line.
768 * Useful for spinlocks to avoid one state transition in the
769 * cache coherency protocol:
771 static inline void prefetchw(const void *x)
773 alternative_input(BASE_PREFETCH, "prefetchw %P1",
774 X86_FEATURE_3DNOWPREFETCH,
775 "m" (*(const char *)x));
778 static inline void spin_lock_prefetch(const void *x)
783 #define TOP_OF_INIT_STACK ((unsigned long)&init_stack + sizeof(init_stack) - \
784 TOP_OF_KERNEL_STACK_PADDING)
788 * User space process size: 3GB (default).
790 #define TASK_SIZE PAGE_OFFSET
791 #define TASK_SIZE_MAX TASK_SIZE
792 #define STACK_TOP TASK_SIZE
793 #define STACK_TOP_MAX STACK_TOP
795 #define INIT_THREAD { \
796 .sp0 = TOP_OF_INIT_STACK, \
797 .sysenter_cs = __KERNEL_CS, \
798 .io_bitmap_ptr = NULL, \
799 .addr_limit = KERNEL_DS, \
803 * TOP_OF_KERNEL_STACK_PADDING reserves 8 bytes on top of the ring0 stack.
804 * This is necessary to guarantee that the entire "struct pt_regs"
805 * is accessible even if the CPU haven't stored the SS/ESP registers
806 * on the stack (interrupt gate does not save these registers
807 * when switching to the same priv ring).
808 * Therefore beware: accessing the ss/esp fields of the
809 * "struct pt_regs" is possible, but they may contain the
810 * completely wrong values.
812 #define task_pt_regs(task) \
814 unsigned long __ptr = (unsigned long)task_stack_page(task); \
815 __ptr += THREAD_SIZE - TOP_OF_KERNEL_STACK_PADDING; \
816 ((struct pt_regs *)__ptr) - 1; \
819 #define KSTK_ESP(task) (task_pt_regs(task)->sp)
823 * User space process size. 47bits minus one guard page. The guard
824 * page is necessary on Intel CPUs: if a SYSCALL instruction is at
825 * the highest possible canonical userspace address, then that
826 * syscall will enter the kernel with a non-canonical return
827 * address, and SYSRET will explode dangerously. We avoid this
828 * particular problem by preventing anything from being mapped
829 * at the maximum canonical address.
831 #define TASK_SIZE_MAX ((1UL << 47) - PAGE_SIZE)
833 /* This decides where the kernel will search for a free chunk of vm
834 * space during mmap's.
836 #define IA32_PAGE_OFFSET ((current->personality & ADDR_LIMIT_3GB) ? \
837 0xc0000000 : 0xFFFFe000)
839 #define TASK_SIZE (test_thread_flag(TIF_ADDR32) ? \
840 IA32_PAGE_OFFSET : TASK_SIZE_MAX)
841 #define TASK_SIZE_OF(child) ((test_tsk_thread_flag(child, TIF_ADDR32)) ? \
842 IA32_PAGE_OFFSET : TASK_SIZE_MAX)
844 #define STACK_TOP TASK_SIZE
845 #define STACK_TOP_MAX TASK_SIZE_MAX
847 #define INIT_THREAD { \
848 .sp0 = TOP_OF_INIT_STACK, \
849 .addr_limit = KERNEL_DS, \
852 #define task_pt_regs(tsk) ((struct pt_regs *)(tsk)->thread.sp0 - 1)
853 extern unsigned long KSTK_ESP(struct task_struct *task);
855 #endif /* CONFIG_X86_64 */
857 extern unsigned long thread_saved_pc(struct task_struct *tsk);
859 extern void start_thread(struct pt_regs *regs, unsigned long new_ip,
860 unsigned long new_sp);
863 * This decides where the kernel will search for a free chunk of vm
864 * space during mmap's.
866 #define TASK_UNMAPPED_BASE (PAGE_ALIGN(TASK_SIZE / 3))
868 #define KSTK_EIP(task) (task_pt_regs(task)->ip)
870 /* Get/set a process' ability to use the timestamp counter instruction */
871 #define GET_TSC_CTL(adr) get_tsc_mode((adr))
872 #define SET_TSC_CTL(val) set_tsc_mode((val))
874 extern int get_tsc_mode(unsigned long adr);
875 extern int set_tsc_mode(unsigned int val);
877 /* Register/unregister a process' MPX related resource */
878 #define MPX_ENABLE_MANAGEMENT() mpx_enable_management()
879 #define MPX_DISABLE_MANAGEMENT() mpx_disable_management()
881 #ifdef CONFIG_X86_INTEL_MPX
882 extern int mpx_enable_management(void);
883 extern int mpx_disable_management(void);
885 static inline int mpx_enable_management(void)
889 static inline int mpx_disable_management(void)
893 #endif /* CONFIG_X86_INTEL_MPX */
895 extern u16 amd_get_nb_id(int cpu);
896 extern u32 amd_get_nodes_per_socket(void);
898 static inline uint32_t hypervisor_cpuid_base(const char *sig, uint32_t leaves)
900 uint32_t base, eax, signature[3];
902 for (base = 0x40000000; base < 0x40010000; base += 0x100) {
903 cpuid(base, &eax, &signature[0], &signature[1], &signature[2]);
905 if (!memcmp(sig, signature, 12) &&
906 (leaves == 0 || ((eax - base) >= leaves)))
913 extern unsigned long arch_align_stack(unsigned long sp);
914 extern void free_init_pages(char *what, unsigned long begin, unsigned long end);
916 void default_idle(void);
918 bool xen_set_default_idle(void);
920 #define xen_set_default_idle 0
923 void stop_this_cpu(void *dummy);
924 void df_debug(struct pt_regs *regs, long error_code);
925 #endif /* _ASM_X86_PROCESSOR_H */