2 * Core of Xen paravirt_ops implementation.
4 * This file contains the xen_paravirt_ops structure itself, and the
6 * - privileged instructions
11 * Jeremy Fitzhardinge <jeremy@xensource.com>, XenSource Inc, 2007
14 #include <linux/cpu.h>
15 #include <linux/kernel.h>
16 #include <linux/init.h>
17 #include <linux/smp.h>
18 #include <linux/preempt.h>
19 #include <linux/hardirq.h>
20 #include <linux/percpu.h>
21 #include <linux/delay.h>
22 #include <linux/start_kernel.h>
23 #include <linux/sched.h>
24 #include <linux/kprobes.h>
25 #include <linux/bootmem.h>
26 #include <linux/module.h>
28 #include <linux/page-flags.h>
29 #include <linux/highmem.h>
30 #include <linux/console.h>
31 #include <linux/pci.h>
32 #include <linux/gfp.h>
33 #include <linux/memblock.h>
34 #include <linux/edd.h>
35 #include <linux/frame.h>
37 #ifdef CONFIG_KEXEC_CORE
38 #include <linux/kexec.h>
42 #include <xen/events.h>
43 #include <xen/interface/xen.h>
44 #include <xen/interface/version.h>
45 #include <xen/interface/physdev.h>
46 #include <xen/interface/vcpu.h>
47 #include <xen/interface/memory.h>
48 #include <xen/interface/nmi.h>
49 #include <xen/interface/xen-mca.h>
50 #include <xen/features.h>
53 #include <xen/hvc-console.h>
56 #include <asm/paravirt.h>
59 #include <asm/xen/pci.h>
60 #include <asm/xen/hypercall.h>
61 #include <asm/xen/hypervisor.h>
62 #include <asm/fixmap.h>
63 #include <asm/processor.h>
64 #include <asm/proto.h>
65 #include <asm/msr-index.h>
66 #include <asm/traps.h>
67 #include <asm/setup.h>
69 #include <asm/pgalloc.h>
70 #include <asm/pgtable.h>
71 #include <asm/tlbflush.h>
72 #include <asm/reboot.h>
73 #include <asm/stackprotector.h>
74 #include <asm/hypervisor.h>
75 #include <asm/mach_traps.h>
76 #include <asm/mwait.h>
77 #include <asm/pci_x86.h>
82 #include <linux/acpi.h>
84 #include <acpi/pdc_intel.h>
85 #include <acpi/processor.h>
86 #include <xen/interface/platform.h>
92 #include "multicalls.h"
95 EXPORT_SYMBOL_GPL(hypercall_page
);
98 * Pointer to the xen_vcpu_info structure or
99 * &HYPERVISOR_shared_info->vcpu_info[cpu]. See xen_hvm_init_shared_info
100 * and xen_vcpu_setup for details. By default it points to share_info->vcpu_info
101 * but if the hypervisor supports VCPUOP_register_vcpu_info then it can point
102 * to xen_vcpu_info. The pointer is used in __xen_evtchn_do_upcall to
103 * acknowledge pending events.
104 * Also more subtly it is used by the patched version of irq enable/disable
105 * e.g. xen_irq_enable_direct and xen_iret in PV mode.
107 * The desire to be able to do those mask/unmask operations as a single
108 * instruction by using the per-cpu offset held in %gs is the real reason
109 * vcpu info is in a per-cpu pointer and the original reason for this
113 DEFINE_PER_CPU(struct vcpu_info
*, xen_vcpu
);
116 * Per CPU pages used if hypervisor supports VCPUOP_register_vcpu_info
117 * hypercall. This can be used both in PV and PVHVM mode. The structure
118 * overrides the default per_cpu(xen_vcpu, cpu) value.
120 DEFINE_PER_CPU(struct vcpu_info
, xen_vcpu_info
);
122 enum xen_domain_type xen_domain_type
= XEN_NATIVE
;
123 EXPORT_SYMBOL_GPL(xen_domain_type
);
125 unsigned long *machine_to_phys_mapping
= (void *)MACH2PHYS_VIRT_START
;
126 EXPORT_SYMBOL(machine_to_phys_mapping
);
127 unsigned long machine_to_phys_nr
;
128 EXPORT_SYMBOL(machine_to_phys_nr
);
130 struct start_info
*xen_start_info
;
131 EXPORT_SYMBOL_GPL(xen_start_info
);
133 struct shared_info xen_dummy_shared_info
;
135 void *xen_initial_gdt
;
137 RESERVE_BRK(shared_info_page_brk
, PAGE_SIZE
);
138 __read_mostly
int xen_have_vector_callback
;
139 EXPORT_SYMBOL_GPL(xen_have_vector_callback
);
142 * Point at some empty memory to start with. We map the real shared_info
143 * page as soon as fixmap is up and running.
145 struct shared_info
*HYPERVISOR_shared_info
= &xen_dummy_shared_info
;
148 * Flag to determine whether vcpu info placement is available on all
149 * VCPUs. We assume it is to start with, and then set it to zero on
150 * the first failure. This is because it can succeed on some VCPUs
151 * and not others, since it can involve hypervisor memory allocation,
152 * or because the guest failed to guarantee all the appropriate
153 * constraints on all VCPUs (ie buffer can't cross a page boundary).
155 * Note that any particular CPU may be using a placed vcpu structure,
156 * but we can only optimise if the all are.
158 * 0: not available, 1: available
160 static int have_vcpu_info_placement
= 1;
163 struct desc_struct desc
[3];
167 * Updating the 3 TLS descriptors in the GDT on every task switch is
168 * surprisingly expensive so we avoid updating them if they haven't
169 * changed. Since Xen writes different descriptors than the one
170 * passed in the update_descriptor hypercall we keep shadow copies to
173 static DEFINE_PER_CPU(struct tls_descs
, shadow_tls_desc
);
175 static void clamp_max_cpus(void)
178 if (setup_max_cpus
> MAX_VIRT_CPUS
)
179 setup_max_cpus
= MAX_VIRT_CPUS
;
183 static void xen_vcpu_setup(int cpu
)
185 struct vcpu_register_vcpu_info info
;
187 struct vcpu_info
*vcpup
;
189 BUG_ON(HYPERVISOR_shared_info
== &xen_dummy_shared_info
);
192 * This path is called twice on PVHVM - first during bootup via
193 * smp_init -> xen_hvm_cpu_notify, and then if the VCPU is being
194 * hotplugged: cpu_up -> xen_hvm_cpu_notify.
195 * As we can only do the VCPUOP_register_vcpu_info once lets
196 * not over-write its result.
198 * For PV it is called during restore (xen_vcpu_restore) and bootup
199 * (xen_setup_vcpu_info_placement). The hotplug mechanism does not
202 if (xen_hvm_domain()) {
203 if (per_cpu(xen_vcpu
, cpu
) == &per_cpu(xen_vcpu_info
, cpu
))
206 if (cpu
< MAX_VIRT_CPUS
)
207 per_cpu(xen_vcpu
,cpu
) = &HYPERVISOR_shared_info
->vcpu_info
[cpu
];
209 if (!have_vcpu_info_placement
) {
210 if (cpu
>= MAX_VIRT_CPUS
)
215 vcpup
= &per_cpu(xen_vcpu_info
, cpu
);
216 info
.mfn
= arbitrary_virt_to_mfn(vcpup
);
217 info
.offset
= offset_in_page(vcpup
);
219 /* Check to see if the hypervisor will put the vcpu_info
220 structure where we want it, which allows direct access via
222 N.B. This hypercall can _only_ be called once per CPU. Subsequent
223 calls will error out with -EINVAL. This is due to the fact that
224 hypervisor has no unregister variant and this hypercall does not
225 allow to over-write info.mfn and info.offset.
227 err
= HYPERVISOR_vcpu_op(VCPUOP_register_vcpu_info
, cpu
, &info
);
230 printk(KERN_DEBUG
"register_vcpu_info failed: err=%d\n", err
);
231 have_vcpu_info_placement
= 0;
234 /* This cpu is using the registered vcpu info, even if
235 later ones fail to. */
236 per_cpu(xen_vcpu
, cpu
) = vcpup
;
241 * On restore, set the vcpu placement up again.
242 * If it fails, then we're in a bad state, since
243 * we can't back out from using it...
245 void xen_vcpu_restore(void)
249 for_each_possible_cpu(cpu
) {
250 bool other_cpu
= (cpu
!= smp_processor_id());
251 bool is_up
= HYPERVISOR_vcpu_op(VCPUOP_is_up
, cpu
, NULL
);
253 if (other_cpu
&& is_up
&&
254 HYPERVISOR_vcpu_op(VCPUOP_down
, cpu
, NULL
))
257 xen_setup_runstate_info(cpu
);
259 if (have_vcpu_info_placement
)
262 if (other_cpu
&& is_up
&&
263 HYPERVISOR_vcpu_op(VCPUOP_up
, cpu
, NULL
))
268 static void __init
xen_banner(void)
270 unsigned version
= HYPERVISOR_xen_version(XENVER_version
, NULL
);
271 struct xen_extraversion extra
;
272 HYPERVISOR_xen_version(XENVER_extraversion
, &extra
);
274 pr_info("Booting paravirtualized kernel %son %s\n",
275 xen_feature(XENFEAT_auto_translated_physmap
) ?
276 "with PVH extensions " : "", pv_info
.name
);
277 printk(KERN_INFO
"Xen version: %d.%d%s%s\n",
278 version
>> 16, version
& 0xffff, extra
.extraversion
,
279 xen_feature(XENFEAT_mmu_pt_update_preserve_ad
) ? " (preserve-AD)" : "");
281 /* Check if running on Xen version (major, minor) or later */
283 xen_running_on_version_or_later(unsigned int major
, unsigned int minor
)
285 unsigned int version
;
290 version
= HYPERVISOR_xen_version(XENVER_version
, NULL
);
291 if ((((version
>> 16) == major
) && ((version
& 0xffff) >= minor
)) ||
292 ((version
>> 16) > major
))
297 #define CPUID_THERM_POWER_LEAF 6
298 #define APERFMPERF_PRESENT 0
300 static __read_mostly
unsigned int cpuid_leaf1_edx_mask
= ~0;
301 static __read_mostly
unsigned int cpuid_leaf1_ecx_mask
= ~0;
303 static __read_mostly
unsigned int cpuid_leaf1_ecx_set_mask
;
304 static __read_mostly
unsigned int cpuid_leaf5_ecx_val
;
305 static __read_mostly
unsigned int cpuid_leaf5_edx_val
;
307 static void xen_cpuid(unsigned int *ax
, unsigned int *bx
,
308 unsigned int *cx
, unsigned int *dx
)
310 unsigned maskebx
= ~0;
311 unsigned maskecx
= ~0;
312 unsigned maskedx
= ~0;
315 * Mask out inconvenient features, to try and disable as many
316 * unsupported kernel subsystems as possible.
320 maskecx
= cpuid_leaf1_ecx_mask
;
321 setecx
= cpuid_leaf1_ecx_set_mask
;
322 maskedx
= cpuid_leaf1_edx_mask
;
325 case CPUID_MWAIT_LEAF
:
326 /* Synthesize the values.. */
329 *cx
= cpuid_leaf5_ecx_val
;
330 *dx
= cpuid_leaf5_edx_val
;
333 case CPUID_THERM_POWER_LEAF
:
334 /* Disabling APERFMPERF for kernel usage */
335 maskecx
= ~(1 << APERFMPERF_PRESENT
);
339 /* Suppress extended topology stuff */
344 asm(XEN_EMULATE_PREFIX
"cpuid"
349 : "0" (*ax
), "2" (*cx
));
356 STACK_FRAME_NON_STANDARD(xen_cpuid
); /* XEN_EMULATE_PREFIX */
358 static bool __init
xen_check_mwait(void)
361 struct xen_platform_op op
= {
362 .cmd
= XENPF_set_processor_pminfo
,
363 .u
.set_pminfo
.id
= -1,
364 .u
.set_pminfo
.type
= XEN_PM_PDC
,
367 unsigned int ax
, bx
, cx
, dx
;
368 unsigned int mwait_mask
;
370 /* We need to determine whether it is OK to expose the MWAIT
371 * capability to the kernel to harvest deeper than C3 states from ACPI
372 * _CST using the processor_harvest_xen.c module. For this to work, we
373 * need to gather the MWAIT_LEAF values (which the cstate.c code
374 * checks against). The hypervisor won't expose the MWAIT flag because
375 * it would break backwards compatibility; so we will find out directly
376 * from the hardware and hypercall.
378 if (!xen_initial_domain())
382 * When running under platform earlier than Xen4.2, do not expose
383 * mwait, to avoid the risk of loading native acpi pad driver
385 if (!xen_running_on_version_or_later(4, 2))
391 native_cpuid(&ax
, &bx
, &cx
, &dx
);
393 mwait_mask
= (1 << (X86_FEATURE_EST
% 32)) |
394 (1 << (X86_FEATURE_MWAIT
% 32));
396 if ((cx
& mwait_mask
) != mwait_mask
)
399 /* We need to emulate the MWAIT_LEAF and for that we need both
400 * ecx and edx. The hypercall provides only partial information.
403 ax
= CPUID_MWAIT_LEAF
;
408 native_cpuid(&ax
, &bx
, &cx
, &dx
);
410 /* Ask the Hypervisor whether to clear ACPI_PDC_C_C2C3_FFH. If so,
411 * don't expose MWAIT_LEAF and let ACPI pick the IOPORT version of C3.
413 buf
[0] = ACPI_PDC_REVISION_ID
;
415 buf
[2] = (ACPI_PDC_C_CAPABILITY_SMP
| ACPI_PDC_EST_CAPABILITY_SWSMP
);
417 set_xen_guest_handle(op
.u
.set_pminfo
.pdc
, buf
);
419 if ((HYPERVISOR_platform_op(&op
) == 0) &&
420 (buf
[2] & (ACPI_PDC_C_C1_FFH
| ACPI_PDC_C_C2C3_FFH
))) {
421 cpuid_leaf5_ecx_val
= cx
;
422 cpuid_leaf5_edx_val
= dx
;
429 static void __init
xen_init_cpuid_mask(void)
431 unsigned int ax
, bx
, cx
, dx
;
432 unsigned int xsave_mask
;
434 cpuid_leaf1_edx_mask
=
435 ~((1 << X86_FEATURE_MTRR
) | /* disable MTRR */
436 (1 << X86_FEATURE_ACC
)); /* thermal monitoring */
438 if (!xen_initial_domain())
439 cpuid_leaf1_edx_mask
&=
440 ~((1 << X86_FEATURE_ACPI
)); /* disable ACPI */
442 cpuid_leaf1_ecx_mask
&= ~(1 << (X86_FEATURE_X2APIC
% 32));
446 cpuid(1, &ax
, &bx
, &cx
, &dx
);
449 (1 << (X86_FEATURE_XSAVE
% 32)) |
450 (1 << (X86_FEATURE_OSXSAVE
% 32));
452 /* Xen will set CR4.OSXSAVE if supported and not disabled by force */
453 if ((cx
& xsave_mask
) != xsave_mask
)
454 cpuid_leaf1_ecx_mask
&= ~xsave_mask
; /* disable XSAVE & OSXSAVE */
455 if (xen_check_mwait())
456 cpuid_leaf1_ecx_set_mask
= (1 << (X86_FEATURE_MWAIT
% 32));
459 static void xen_set_debugreg(int reg
, unsigned long val
)
461 HYPERVISOR_set_debugreg(reg
, val
);
464 static unsigned long xen_get_debugreg(int reg
)
466 return HYPERVISOR_get_debugreg(reg
);
469 static void xen_end_context_switch(struct task_struct
*next
)
472 paravirt_end_context_switch(next
);
475 static unsigned long xen_store_tr(void)
481 * Set the page permissions for a particular virtual address. If the
482 * address is a vmalloc mapping (or other non-linear mapping), then
483 * find the linear mapping of the page and also set its protections to
486 static void set_aliased_prot(void *v
, pgprot_t prot
)
495 ptep
= lookup_address((unsigned long)v
, &level
);
496 BUG_ON(ptep
== NULL
);
498 pfn
= pte_pfn(*ptep
);
499 page
= pfn_to_page(pfn
);
501 pte
= pfn_pte(pfn
, prot
);
504 * Careful: update_va_mapping() will fail if the virtual address
505 * we're poking isn't populated in the page tables. We don't
506 * need to worry about the direct map (that's always in the page
507 * tables), but we need to be careful about vmap space. In
508 * particular, the top level page table can lazily propagate
509 * entries between processes, so if we've switched mms since we
510 * vmapped the target in the first place, we might not have the
511 * top-level page table entry populated.
513 * We disable preemption because we want the same mm active when
514 * we probe the target and when we issue the hypercall. We'll
515 * have the same nominal mm, but if we're a kernel thread, lazy
516 * mm dropping could change our pgd.
518 * Out of an abundance of caution, this uses __get_user() to fault
519 * in the target address just in case there's some obscure case
520 * in which the target address isn't readable.
525 pagefault_disable(); /* Avoid warnings due to being atomic. */
526 __get_user(dummy
, (unsigned char __user __force
*)v
);
529 if (HYPERVISOR_update_va_mapping((unsigned long)v
, pte
, 0))
532 if (!PageHighMem(page
)) {
533 void *av
= __va(PFN_PHYS(pfn
));
536 if (HYPERVISOR_update_va_mapping((unsigned long)av
, pte
, 0))
544 static void xen_alloc_ldt(struct desc_struct
*ldt
, unsigned entries
)
546 const unsigned entries_per_page
= PAGE_SIZE
/ LDT_ENTRY_SIZE
;
550 * We need to mark the all aliases of the LDT pages RO. We
551 * don't need to call vm_flush_aliases(), though, since that's
552 * only responsible for flushing aliases out the TLBs, not the
553 * page tables, and Xen will flush the TLB for us if needed.
555 * To avoid confusing future readers: none of this is necessary
556 * to load the LDT. The hypervisor only checks this when the
557 * LDT is faulted in due to subsequent descriptor access.
560 for(i
= 0; i
< entries
; i
+= entries_per_page
)
561 set_aliased_prot(ldt
+ i
, PAGE_KERNEL_RO
);
564 static void xen_free_ldt(struct desc_struct
*ldt
, unsigned entries
)
566 const unsigned entries_per_page
= PAGE_SIZE
/ LDT_ENTRY_SIZE
;
569 for(i
= 0; i
< entries
; i
+= entries_per_page
)
570 set_aliased_prot(ldt
+ i
, PAGE_KERNEL
);
573 static void xen_set_ldt(const void *addr
, unsigned entries
)
575 struct mmuext_op
*op
;
576 struct multicall_space mcs
= xen_mc_entry(sizeof(*op
));
578 trace_xen_cpu_set_ldt(addr
, entries
);
581 op
->cmd
= MMUEXT_SET_LDT
;
582 op
->arg1
.linear_addr
= (unsigned long)addr
;
583 op
->arg2
.nr_ents
= entries
;
585 MULTI_mmuext_op(mcs
.mc
, op
, 1, NULL
, DOMID_SELF
);
587 xen_mc_issue(PARAVIRT_LAZY_CPU
);
590 static void xen_load_gdt(const struct desc_ptr
*dtr
)
592 unsigned long va
= dtr
->address
;
593 unsigned int size
= dtr
->size
+ 1;
594 unsigned pages
= (size
+ PAGE_SIZE
- 1) / PAGE_SIZE
;
595 unsigned long frames
[pages
];
599 * A GDT can be up to 64k in size, which corresponds to 8192
600 * 8-byte entries, or 16 4k pages..
603 BUG_ON(size
> 65536);
604 BUG_ON(va
& ~PAGE_MASK
);
606 for (f
= 0; va
< dtr
->address
+ size
; va
+= PAGE_SIZE
, f
++) {
609 unsigned long pfn
, mfn
;
613 * The GDT is per-cpu and is in the percpu data area.
614 * That can be virtually mapped, so we need to do a
615 * page-walk to get the underlying MFN for the
616 * hypercall. The page can also be in the kernel's
617 * linear range, so we need to RO that mapping too.
619 ptep
= lookup_address(va
, &level
);
620 BUG_ON(ptep
== NULL
);
622 pfn
= pte_pfn(*ptep
);
623 mfn
= pfn_to_mfn(pfn
);
624 virt
= __va(PFN_PHYS(pfn
));
628 make_lowmem_page_readonly((void *)va
);
629 make_lowmem_page_readonly(virt
);
632 if (HYPERVISOR_set_gdt(frames
, size
/ sizeof(struct desc_struct
)))
637 * load_gdt for early boot, when the gdt is only mapped once
639 static void __init
xen_load_gdt_boot(const struct desc_ptr
*dtr
)
641 unsigned long va
= dtr
->address
;
642 unsigned int size
= dtr
->size
+ 1;
643 unsigned pages
= (size
+ PAGE_SIZE
- 1) / PAGE_SIZE
;
644 unsigned long frames
[pages
];
648 * A GDT can be up to 64k in size, which corresponds to 8192
649 * 8-byte entries, or 16 4k pages..
652 BUG_ON(size
> 65536);
653 BUG_ON(va
& ~PAGE_MASK
);
655 for (f
= 0; va
< dtr
->address
+ size
; va
+= PAGE_SIZE
, f
++) {
657 unsigned long pfn
, mfn
;
659 pfn
= virt_to_pfn(va
);
660 mfn
= pfn_to_mfn(pfn
);
662 pte
= pfn_pte(pfn
, PAGE_KERNEL_RO
);
664 if (HYPERVISOR_update_va_mapping((unsigned long)va
, pte
, 0))
670 if (HYPERVISOR_set_gdt(frames
, size
/ sizeof(struct desc_struct
)))
674 static inline bool desc_equal(const struct desc_struct
*d1
,
675 const struct desc_struct
*d2
)
677 return d1
->a
== d2
->a
&& d1
->b
== d2
->b
;
680 static void load_TLS_descriptor(struct thread_struct
*t
,
681 unsigned int cpu
, unsigned int i
)
683 struct desc_struct
*shadow
= &per_cpu(shadow_tls_desc
, cpu
).desc
[i
];
684 struct desc_struct
*gdt
;
686 struct multicall_space mc
;
688 if (desc_equal(shadow
, &t
->tls_array
[i
]))
691 *shadow
= t
->tls_array
[i
];
693 gdt
= get_cpu_gdt_table(cpu
);
694 maddr
= arbitrary_virt_to_machine(&gdt
[GDT_ENTRY_TLS_MIN
+i
]);
695 mc
= __xen_mc_entry(0);
697 MULTI_update_descriptor(mc
.mc
, maddr
.maddr
, t
->tls_array
[i
]);
700 static void xen_load_tls(struct thread_struct
*t
, unsigned int cpu
)
703 * XXX sleazy hack: If we're being called in a lazy-cpu zone
704 * and lazy gs handling is enabled, it means we're in a
705 * context switch, and %gs has just been saved. This means we
706 * can zero it out to prevent faults on exit from the
707 * hypervisor if the next process has no %gs. Either way, it
708 * has been saved, and the new value will get loaded properly.
709 * This will go away as soon as Xen has been modified to not
710 * save/restore %gs for normal hypercalls.
712 * On x86_64, this hack is not used for %gs, because gs points
713 * to KERNEL_GS_BASE (and uses it for PDA references), so we
714 * must not zero %gs on x86_64
716 * For x86_64, we need to zero %fs, otherwise we may get an
717 * exception between the new %fs descriptor being loaded and
718 * %fs being effectively cleared at __switch_to().
720 if (paravirt_get_lazy_mode() == PARAVIRT_LAZY_CPU
) {
730 load_TLS_descriptor(t
, cpu
, 0);
731 load_TLS_descriptor(t
, cpu
, 1);
732 load_TLS_descriptor(t
, cpu
, 2);
734 xen_mc_issue(PARAVIRT_LAZY_CPU
);
738 static void xen_load_gs_index(unsigned int idx
)
740 if (HYPERVISOR_set_segment_base(SEGBASE_GS_USER_SEL
, idx
))
745 static void xen_write_ldt_entry(struct desc_struct
*dt
, int entrynum
,
748 xmaddr_t mach_lp
= arbitrary_virt_to_machine(&dt
[entrynum
]);
749 u64 entry
= *(u64
*)ptr
;
751 trace_xen_cpu_write_ldt_entry(dt
, entrynum
, entry
);
756 if (HYPERVISOR_update_descriptor(mach_lp
.maddr
, entry
))
762 static int cvt_gate_to_trap(int vector
, const gate_desc
*val
,
763 struct trap_info
*info
)
767 if (val
->type
!= GATE_TRAP
&& val
->type
!= GATE_INTERRUPT
)
770 info
->vector
= vector
;
772 addr
= gate_offset(*val
);
775 * Look for known traps using IST, and substitute them
776 * appropriately. The debugger ones are the only ones we care
777 * about. Xen will handle faults like double_fault,
778 * so we should never see them. Warn if
779 * there's an unexpected IST-using fault handler.
781 if (addr
== (unsigned long)debug
)
782 addr
= (unsigned long)xen_debug
;
783 else if (addr
== (unsigned long)int3
)
784 addr
= (unsigned long)xen_int3
;
785 else if (addr
== (unsigned long)stack_segment
)
786 addr
= (unsigned long)xen_stack_segment
;
787 else if (addr
== (unsigned long)double_fault
) {
788 /* Don't need to handle these */
790 #ifdef CONFIG_X86_MCE
791 } else if (addr
== (unsigned long)machine_check
) {
793 * when xen hypervisor inject vMCE to guest,
794 * use native mce handler to handle it
798 } else if (addr
== (unsigned long)nmi
)
800 * Use the native version as well.
804 /* Some other trap using IST? */
805 if (WARN_ON(val
->ist
!= 0))
808 #endif /* CONFIG_X86_64 */
809 info
->address
= addr
;
811 info
->cs
= gate_segment(*val
);
812 info
->flags
= val
->dpl
;
813 /* interrupt gates clear IF */
814 if (val
->type
== GATE_INTERRUPT
)
815 info
->flags
|= 1 << 2;
820 /* Locations of each CPU's IDT */
821 static DEFINE_PER_CPU(struct desc_ptr
, idt_desc
);
823 /* Set an IDT entry. If the entry is part of the current IDT, then
825 static void xen_write_idt_entry(gate_desc
*dt
, int entrynum
, const gate_desc
*g
)
827 unsigned long p
= (unsigned long)&dt
[entrynum
];
828 unsigned long start
, end
;
830 trace_xen_cpu_write_idt_entry(dt
, entrynum
, g
);
834 start
= __this_cpu_read(idt_desc
.address
);
835 end
= start
+ __this_cpu_read(idt_desc
.size
) + 1;
839 native_write_idt_entry(dt
, entrynum
, g
);
841 if (p
>= start
&& (p
+ 8) <= end
) {
842 struct trap_info info
[2];
846 if (cvt_gate_to_trap(entrynum
, g
, &info
[0]))
847 if (HYPERVISOR_set_trap_table(info
))
854 static void xen_convert_trap_info(const struct desc_ptr
*desc
,
855 struct trap_info
*traps
)
857 unsigned in
, out
, count
;
859 count
= (desc
->size
+1) / sizeof(gate_desc
);
862 for (in
= out
= 0; in
< count
; in
++) {
863 gate_desc
*entry
= (gate_desc
*)(desc
->address
) + in
;
865 if (cvt_gate_to_trap(in
, entry
, &traps
[out
]))
868 traps
[out
].address
= 0;
871 void xen_copy_trap_info(struct trap_info
*traps
)
873 const struct desc_ptr
*desc
= this_cpu_ptr(&idt_desc
);
875 xen_convert_trap_info(desc
, traps
);
878 /* Load a new IDT into Xen. In principle this can be per-CPU, so we
879 hold a spinlock to protect the static traps[] array (static because
880 it avoids allocation, and saves stack space). */
881 static void xen_load_idt(const struct desc_ptr
*desc
)
883 static DEFINE_SPINLOCK(lock
);
884 static struct trap_info traps
[257];
886 trace_xen_cpu_load_idt(desc
);
890 memcpy(this_cpu_ptr(&idt_desc
), desc
, sizeof(idt_desc
));
892 xen_convert_trap_info(desc
, traps
);
895 if (HYPERVISOR_set_trap_table(traps
))
901 /* Write a GDT descriptor entry. Ignore LDT descriptors, since
902 they're handled differently. */
903 static void xen_write_gdt_entry(struct desc_struct
*dt
, int entry
,
904 const void *desc
, int type
)
906 trace_xen_cpu_write_gdt_entry(dt
, entry
, desc
, type
);
917 xmaddr_t maddr
= arbitrary_virt_to_machine(&dt
[entry
]);
920 if (HYPERVISOR_update_descriptor(maddr
.maddr
, *(u64
*)desc
))
930 * Version of write_gdt_entry for use at early boot-time needed to
931 * update an entry as simply as possible.
933 static void __init
xen_write_gdt_entry_boot(struct desc_struct
*dt
, int entry
,
934 const void *desc
, int type
)
936 trace_xen_cpu_write_gdt_entry(dt
, entry
, desc
, type
);
945 xmaddr_t maddr
= virt_to_machine(&dt
[entry
]);
947 if (HYPERVISOR_update_descriptor(maddr
.maddr
, *(u64
*)desc
))
948 dt
[entry
] = *(struct desc_struct
*)desc
;
954 static void xen_load_sp0(struct tss_struct
*tss
,
955 struct thread_struct
*thread
)
957 struct multicall_space mcs
;
959 mcs
= xen_mc_entry(0);
960 MULTI_stack_switch(mcs
.mc
, __KERNEL_DS
, thread
->sp0
);
961 xen_mc_issue(PARAVIRT_LAZY_CPU
);
962 tss
->x86_tss
.sp0
= thread
->sp0
;
965 void xen_set_iopl_mask(unsigned mask
)
967 struct physdev_set_iopl set_iopl
;
969 /* Force the change at ring 0. */
970 set_iopl
.iopl
= (mask
== 0) ? 1 : (mask
>> 12) & 3;
971 HYPERVISOR_physdev_op(PHYSDEVOP_set_iopl
, &set_iopl
);
974 static void xen_io_delay(void)
978 static void xen_clts(void)
980 struct multicall_space mcs
;
982 mcs
= xen_mc_entry(0);
984 MULTI_fpu_taskswitch(mcs
.mc
, 0);
986 xen_mc_issue(PARAVIRT_LAZY_CPU
);
989 static DEFINE_PER_CPU(unsigned long, xen_cr0_value
);
991 static unsigned long xen_read_cr0(void)
993 unsigned long cr0
= this_cpu_read(xen_cr0_value
);
995 if (unlikely(cr0
== 0)) {
996 cr0
= native_read_cr0();
997 this_cpu_write(xen_cr0_value
, cr0
);
1003 static void xen_write_cr0(unsigned long cr0
)
1005 struct multicall_space mcs
;
1007 this_cpu_write(xen_cr0_value
, cr0
);
1009 /* Only pay attention to cr0.TS; everything else is
1011 mcs
= xen_mc_entry(0);
1013 MULTI_fpu_taskswitch(mcs
.mc
, (cr0
& X86_CR0_TS
) != 0);
1015 xen_mc_issue(PARAVIRT_LAZY_CPU
);
1018 static void xen_write_cr4(unsigned long cr4
)
1020 cr4
&= ~(X86_CR4_PGE
| X86_CR4_PSE
| X86_CR4_PCE
);
1022 native_write_cr4(cr4
);
1024 #ifdef CONFIG_X86_64
1025 static inline unsigned long xen_read_cr8(void)
1029 static inline void xen_write_cr8(unsigned long val
)
1035 static u64
xen_read_msr_safe(unsigned int msr
, int *err
)
1039 if (pmu_msr_read(msr
, &val
, err
))
1042 val
= native_read_msr_safe(msr
, err
);
1044 case MSR_IA32_APICBASE
:
1045 #ifdef CONFIG_X86_X2APIC
1046 if (!(cpuid_ecx(1) & (1 << (X86_FEATURE_X2APIC
& 31))))
1048 val
&= ~X2APIC_ENABLE
;
1054 static int xen_write_msr_safe(unsigned int msr
, unsigned low
, unsigned high
)
1061 #ifdef CONFIG_X86_64
1065 case MSR_FS_BASE
: which
= SEGBASE_FS
; goto set
;
1066 case MSR_KERNEL_GS_BASE
: which
= SEGBASE_GS_USER
; goto set
;
1067 case MSR_GS_BASE
: which
= SEGBASE_GS_KERNEL
; goto set
;
1070 base
= ((u64
)high
<< 32) | low
;
1071 if (HYPERVISOR_set_segment_base(which
, base
) != 0)
1079 case MSR_SYSCALL_MASK
:
1080 case MSR_IA32_SYSENTER_CS
:
1081 case MSR_IA32_SYSENTER_ESP
:
1082 case MSR_IA32_SYSENTER_EIP
:
1083 /* Fast syscall setup is all done in hypercalls, so
1084 these are all ignored. Stub them out here to stop
1085 Xen console noise. */
1089 if (!pmu_msr_write(msr
, low
, high
, &ret
))
1090 ret
= native_write_msr_safe(msr
, low
, high
);
1096 void xen_setup_shared_info(void)
1098 if (!xen_feature(XENFEAT_auto_translated_physmap
)) {
1099 set_fixmap(FIX_PARAVIRT_BOOTMAP
,
1100 xen_start_info
->shared_info
);
1102 HYPERVISOR_shared_info
=
1103 (struct shared_info
*)fix_to_virt(FIX_PARAVIRT_BOOTMAP
);
1105 HYPERVISOR_shared_info
=
1106 (struct shared_info
*)__va(xen_start_info
->shared_info
);
1109 /* In UP this is as good a place as any to set up shared info */
1110 xen_setup_vcpu_info_placement();
1113 xen_setup_mfn_list_list();
1116 /* This is called once we have the cpu_possible_mask */
1117 void xen_setup_vcpu_info_placement(void)
1121 for_each_possible_cpu(cpu
)
1122 xen_vcpu_setup(cpu
);
1124 /* xen_vcpu_setup managed to place the vcpu_info within the
1125 * percpu area for all cpus, so make use of it. Note that for
1126 * PVH we want to use native IRQ mechanism. */
1127 if (have_vcpu_info_placement
&& !xen_pvh_domain()) {
1128 pv_irq_ops
.save_fl
= __PV_IS_CALLEE_SAVE(xen_save_fl_direct
);
1129 pv_irq_ops
.restore_fl
= __PV_IS_CALLEE_SAVE(xen_restore_fl_direct
);
1130 pv_irq_ops
.irq_disable
= __PV_IS_CALLEE_SAVE(xen_irq_disable_direct
);
1131 pv_irq_ops
.irq_enable
= __PV_IS_CALLEE_SAVE(xen_irq_enable_direct
);
1132 pv_mmu_ops
.read_cr2
= xen_read_cr2_direct
;
1136 static unsigned xen_patch(u8 type
, u16 clobbers
, void *insnbuf
,
1137 unsigned long addr
, unsigned len
)
1139 char *start
, *end
, *reloc
;
1142 start
= end
= reloc
= NULL
;
1144 #define SITE(op, x) \
1145 case PARAVIRT_PATCH(op.x): \
1146 if (have_vcpu_info_placement) { \
1147 start = (char *)xen_##x##_direct; \
1148 end = xen_##x##_direct_end; \
1149 reloc = xen_##x##_direct_reloc; \
1154 SITE(pv_irq_ops
, irq_enable
);
1155 SITE(pv_irq_ops
, irq_disable
);
1156 SITE(pv_irq_ops
, save_fl
);
1157 SITE(pv_irq_ops
, restore_fl
);
1161 if (start
== NULL
|| (end
-start
) > len
)
1164 ret
= paravirt_patch_insns(insnbuf
, len
, start
, end
);
1166 /* Note: because reloc is assigned from something that
1167 appears to be an array, gcc assumes it's non-null,
1168 but doesn't know its relationship with start and
1170 if (reloc
> start
&& reloc
< end
) {
1171 int reloc_off
= reloc
- start
;
1172 long *relocp
= (long *)(insnbuf
+ reloc_off
);
1173 long delta
= start
- (char *)addr
;
1181 ret
= paravirt_patch_default(type
, clobbers
, insnbuf
,
1189 static const struct pv_info xen_info __initconst
= {
1190 .paravirt_enabled
= 1,
1191 .shared_kernel_pmd
= 0,
1193 #ifdef CONFIG_X86_64
1194 .extra_user_64bit_cs
= FLAT_USER_CS64
,
1200 static const struct pv_init_ops xen_init_ops __initconst
= {
1204 static const struct pv_cpu_ops xen_cpu_ops __initconst
= {
1207 .set_debugreg
= xen_set_debugreg
,
1208 .get_debugreg
= xen_get_debugreg
,
1212 .read_cr0
= xen_read_cr0
,
1213 .write_cr0
= xen_write_cr0
,
1215 .read_cr4
= native_read_cr4
,
1216 .read_cr4_safe
= native_read_cr4_safe
,
1217 .write_cr4
= xen_write_cr4
,
1219 #ifdef CONFIG_X86_64
1220 .read_cr8
= xen_read_cr8
,
1221 .write_cr8
= xen_write_cr8
,
1224 .wbinvd
= native_wbinvd
,
1226 .read_msr
= xen_read_msr_safe
,
1227 .write_msr
= xen_write_msr_safe
,
1229 .read_pmc
= xen_read_pmc
,
1232 #ifdef CONFIG_X86_64
1233 .usergs_sysret64
= xen_sysret64
,
1236 .load_tr_desc
= paravirt_nop
,
1237 .set_ldt
= xen_set_ldt
,
1238 .load_gdt
= xen_load_gdt
,
1239 .load_idt
= xen_load_idt
,
1240 .load_tls
= xen_load_tls
,
1241 #ifdef CONFIG_X86_64
1242 .load_gs_index
= xen_load_gs_index
,
1245 .alloc_ldt
= xen_alloc_ldt
,
1246 .free_ldt
= xen_free_ldt
,
1248 .store_idt
= native_store_idt
,
1249 .store_tr
= xen_store_tr
,
1251 .write_ldt_entry
= xen_write_ldt_entry
,
1252 .write_gdt_entry
= xen_write_gdt_entry
,
1253 .write_idt_entry
= xen_write_idt_entry
,
1254 .load_sp0
= xen_load_sp0
,
1256 .set_iopl_mask
= xen_set_iopl_mask
,
1257 .io_delay
= xen_io_delay
,
1259 /* Xen takes care of %gs when switching to usermode for us */
1260 .swapgs
= paravirt_nop
,
1262 .start_context_switch
= paravirt_start_context_switch
,
1263 .end_context_switch
= xen_end_context_switch
,
1266 static void xen_reboot(int reason
)
1268 struct sched_shutdown r
= { .reason
= reason
};
1271 for_each_online_cpu(cpu
)
1272 xen_pmu_finish(cpu
);
1274 if (HYPERVISOR_sched_op(SCHEDOP_shutdown
, &r
))
1278 static void xen_restart(char *msg
)
1280 xen_reboot(SHUTDOWN_reboot
);
1283 static void xen_emergency_restart(void)
1285 xen_reboot(SHUTDOWN_reboot
);
1288 static void xen_machine_halt(void)
1290 xen_reboot(SHUTDOWN_poweroff
);
1293 static void xen_machine_power_off(void)
1297 xen_reboot(SHUTDOWN_poweroff
);
1300 static void xen_crash_shutdown(struct pt_regs
*regs
)
1302 xen_reboot(SHUTDOWN_crash
);
1306 xen_panic_event(struct notifier_block
*this, unsigned long event
, void *ptr
)
1308 xen_reboot(SHUTDOWN_crash
);
1312 static struct notifier_block xen_panic_block
= {
1313 .notifier_call
= xen_panic_event
,
1317 int xen_panic_handler_init(void)
1319 atomic_notifier_chain_register(&panic_notifier_list
, &xen_panic_block
);
1323 static const struct machine_ops xen_machine_ops __initconst
= {
1324 .restart
= xen_restart
,
1325 .halt
= xen_machine_halt
,
1326 .power_off
= xen_machine_power_off
,
1327 .shutdown
= xen_machine_halt
,
1328 .crash_shutdown
= xen_crash_shutdown
,
1329 .emergency_restart
= xen_emergency_restart
,
1332 static unsigned char xen_get_nmi_reason(void)
1334 unsigned char reason
= 0;
1336 /* Construct a value which looks like it came from port 0x61. */
1337 if (test_bit(_XEN_NMIREASON_io_error
,
1338 &HYPERVISOR_shared_info
->arch
.nmi_reason
))
1339 reason
|= NMI_REASON_IOCHK
;
1340 if (test_bit(_XEN_NMIREASON_pci_serr
,
1341 &HYPERVISOR_shared_info
->arch
.nmi_reason
))
1342 reason
|= NMI_REASON_SERR
;
1347 static void __init
xen_boot_params_init_edd(void)
1349 #if IS_ENABLED(CONFIG_EDD)
1350 struct xen_platform_op op
;
1351 struct edd_info
*edd_info
;
1356 edd_info
= boot_params
.eddbuf
;
1357 mbr_signature
= boot_params
.edd_mbr_sig_buffer
;
1359 op
.cmd
= XENPF_firmware_info
;
1361 op
.u
.firmware_info
.type
= XEN_FW_DISK_INFO
;
1362 for (nr
= 0; nr
< EDDMAXNR
; nr
++) {
1363 struct edd_info
*info
= edd_info
+ nr
;
1365 op
.u
.firmware_info
.index
= nr
;
1366 info
->params
.length
= sizeof(info
->params
);
1367 set_xen_guest_handle(op
.u
.firmware_info
.u
.disk_info
.edd_params
,
1369 ret
= HYPERVISOR_platform_op(&op
);
1373 #define C(x) info->x = op.u.firmware_info.u.disk_info.x
1376 C(interface_support
);
1377 C(legacy_max_cylinder
);
1379 C(legacy_sectors_per_track
);
1382 boot_params
.eddbuf_entries
= nr
;
1384 op
.u
.firmware_info
.type
= XEN_FW_DISK_MBR_SIGNATURE
;
1385 for (nr
= 0; nr
< EDD_MBR_SIG_MAX
; nr
++) {
1386 op
.u
.firmware_info
.index
= nr
;
1387 ret
= HYPERVISOR_platform_op(&op
);
1390 mbr_signature
[nr
] = op
.u
.firmware_info
.u
.disk_mbr_signature
.mbr_signature
;
1392 boot_params
.edd_mbr_sig_buf_entries
= nr
;
1397 * Set up the GDT and segment registers for -fstack-protector. Until
1398 * we do this, we have to be careful not to call any stack-protected
1399 * function, which is most of the kernel.
1401 * Note, that it is __ref because the only caller of this after init
1402 * is PVH which is not going to use xen_load_gdt_boot or other
1405 static void __ref
xen_setup_gdt(int cpu
)
1407 if (xen_feature(XENFEAT_auto_translated_physmap
)) {
1408 #ifdef CONFIG_X86_64
1409 unsigned long dummy
;
1411 load_percpu_segment(cpu
); /* We need to access per-cpu area */
1412 switch_to_new_gdt(cpu
); /* GDT and GS set */
1414 /* We are switching of the Xen provided GDT to our HVM mode
1415 * GDT. The new GDT has __KERNEL_CS with CS.L = 1
1416 * and we are jumping to reload it.
1418 asm volatile ("pushq %0\n"
1419 "leaq 1f(%%rip),%0\n"
1423 : "=&r" (dummy
) : "0" (__KERNEL_CS
));
1426 * While not needed, we also set the %es, %ds, and %fs
1427 * to zero. We don't care about %ss as it is NULL.
1428 * Strictly speaking this is not needed as Xen zeros those
1429 * out (and also MSR_FS_BASE, MSR_GS_BASE, MSR_KERNEL_GS_BASE)
1431 * Linux zeros them in cpu_init() and in secondary_startup_64
1438 /* PVH: TODO Implement. */
1441 return; /* PVH does not need any PV GDT ops. */
1443 pv_cpu_ops
.write_gdt_entry
= xen_write_gdt_entry_boot
;
1444 pv_cpu_ops
.load_gdt
= xen_load_gdt_boot
;
1446 setup_stack_canary_segment(0);
1447 switch_to_new_gdt(0);
1449 pv_cpu_ops
.write_gdt_entry
= xen_write_gdt_entry
;
1450 pv_cpu_ops
.load_gdt
= xen_load_gdt
;
1453 #ifdef CONFIG_XEN_PVH
1455 * A PV guest starts with default flags that are not set for PVH, set them
1458 static void xen_pvh_set_cr_flags(int cpu
)
1461 /* Some of these are setup in 'secondary_startup_64'. The others:
1462 * X86_CR0_TS, X86_CR0_PE, X86_CR0_ET are set by Xen for HVM guests
1463 * (which PVH shared codepaths), while X86_CR0_PG is for PVH. */
1464 write_cr0(read_cr0() | X86_CR0_MP
| X86_CR0_NE
| X86_CR0_WP
| X86_CR0_AM
);
1469 * For BSP, PSE PGE are set in probe_page_size_mask(), for APs
1470 * set them here. For all, OSFXSR OSXMMEXCPT are set in fpu__init_cpu().
1473 cr4_set_bits_and_update_boot(X86_CR4_PSE
);
1476 cr4_set_bits_and_update_boot(X86_CR4_PGE
);
1480 * Note, that it is ref - because the only caller of this after init
1481 * is PVH which is not going to use xen_load_gdt_boot or other
1484 void __ref
xen_pvh_secondary_vcpu_init(int cpu
)
1487 xen_pvh_set_cr_flags(cpu
);
1490 static void __init
xen_pvh_early_guest_init(void)
1492 if (!xen_feature(XENFEAT_auto_translated_physmap
))
1495 if (!xen_feature(XENFEAT_hvm_callback_vector
))
1498 xen_have_vector_callback
= 1;
1500 xen_pvh_early_cpu_init(0, false);
1501 xen_pvh_set_cr_flags(0);
1503 #ifdef CONFIG_X86_32
1504 BUG(); /* PVH: Implement proper support. */
1507 #endif /* CONFIG_XEN_PVH */
1509 /* First C function to be called on Xen boot */
1510 asmlinkage __visible
void __init
xen_start_kernel(void)
1512 struct physdev_set_iopl set_iopl
;
1513 unsigned long initrd_start
= 0;
1517 if (!xen_start_info
)
1520 xen_domain_type
= XEN_PV_DOMAIN
;
1522 xen_setup_features();
1523 #ifdef CONFIG_XEN_PVH
1524 xen_pvh_early_guest_init();
1526 xen_setup_machphys_mapping();
1528 /* Install Xen paravirt ops */
1530 if (xen_initial_domain())
1531 pv_info
.features
|= PV_SUPPORTED_RTC
;
1532 pv_init_ops
= xen_init_ops
;
1533 if (!xen_pvh_domain()) {
1534 pv_cpu_ops
= xen_cpu_ops
;
1536 x86_platform
.get_nmi_reason
= xen_get_nmi_reason
;
1539 if (xen_feature(XENFEAT_auto_translated_physmap
))
1540 x86_init
.resources
.memory_setup
= xen_auto_xlated_memory_setup
;
1542 x86_init
.resources
.memory_setup
= xen_memory_setup
;
1543 x86_init
.oem
.arch_setup
= xen_arch_setup
;
1544 x86_init
.oem
.banner
= xen_banner
;
1546 xen_init_time_ops();
1549 * Set up some pagetable state before starting to set any ptes.
1554 /* Prevent unwanted bits from being set in PTEs. */
1555 __supported_pte_mask
&= ~_PAGE_GLOBAL
;
1558 * Prevent page tables from being allocated in highmem, even
1559 * if CONFIG_HIGHPTE is enabled.
1561 __userpte_alloc_gfp
&= ~__GFP_HIGHMEM
;
1563 /* Work out if we support NX */
1567 xen_build_dynamic_phys_to_machine();
1570 * Set up kernel GDT and segment registers, mainly so that
1571 * -fstack-protector code can be executed.
1576 xen_init_cpuid_mask();
1578 #ifdef CONFIG_X86_LOCAL_APIC
1580 * set up the basic apic ops.
1585 if (xen_feature(XENFEAT_mmu_pt_update_preserve_ad
)) {
1586 pv_mmu_ops
.ptep_modify_prot_start
= xen_ptep_modify_prot_start
;
1587 pv_mmu_ops
.ptep_modify_prot_commit
= xen_ptep_modify_prot_commit
;
1590 machine_ops
= xen_machine_ops
;
1593 * The only reliable way to retain the initial address of the
1594 * percpu gdt_page is to remember it here, so we can go and
1595 * mark it RW later, when the initial percpu area is freed.
1597 xen_initial_gdt
= &per_cpu(gdt_page
, 0);
1601 #ifdef CONFIG_ACPI_NUMA
1603 * The pages we from Xen are not related to machine pages, so
1604 * any NUMA information the kernel tries to get from ACPI will
1605 * be meaningless. Prevent it from trying.
1609 /* Don't do the full vcpu_info placement stuff until we have a
1610 possible map and a non-dummy shared_info. */
1611 per_cpu(xen_vcpu
, 0) = &HYPERVISOR_shared_info
->vcpu_info
[0];
1613 local_irq_disable();
1614 early_boot_irqs_disabled
= true;
1616 xen_raw_console_write("mapping kernel into physical memory\n");
1617 xen_setup_kernel_pagetable((pgd_t
*)xen_start_info
->pt_base
,
1618 xen_start_info
->nr_pages
);
1619 xen_reserve_special_pages();
1622 * Modify the cache mode translation tables to match Xen's PAT
1625 rdmsrl(MSR_IA32_CR_PAT
, pat
);
1626 pat_init_cache_modes(pat
);
1628 /* keep using Xen gdt for now; no urgent need to change it */
1630 #ifdef CONFIG_X86_32
1631 pv_info
.kernel_rpl
= 1;
1632 if (xen_feature(XENFEAT_supervisor_mode_kernel
))
1633 pv_info
.kernel_rpl
= 0;
1635 pv_info
.kernel_rpl
= 0;
1637 /* set the limit of our address space */
1640 /* PVH: runs at default kernel iopl of 0 */
1641 if (!xen_pvh_domain()) {
1643 * We used to do this in xen_arch_setup, but that is too late
1644 * on AMD were early_cpu_init (run before ->arch_setup()) calls
1645 * early_amd_init which pokes 0xcf8 port.
1648 rc
= HYPERVISOR_physdev_op(PHYSDEVOP_set_iopl
, &set_iopl
);
1650 xen_raw_printk("physdev_op failed %d\n", rc
);
1653 #ifdef CONFIG_X86_32
1654 /* set up basic CPUID stuff */
1655 cpu_detect(&new_cpu_data
);
1656 set_cpu_cap(&new_cpu_data
, X86_FEATURE_FPU
);
1657 new_cpu_data
.wp_works_ok
= 1;
1658 new_cpu_data
.x86_capability
[CPUID_1_EDX
] = cpuid_edx(1);
1661 if (xen_start_info
->mod_start
) {
1662 if (xen_start_info
->flags
& SIF_MOD_START_PFN
)
1663 initrd_start
= PFN_PHYS(xen_start_info
->mod_start
);
1665 initrd_start
= __pa(xen_start_info
->mod_start
);
1668 /* Poke various useful things into boot_params */
1669 boot_params
.hdr
.type_of_loader
= (9 << 4) | 0;
1670 boot_params
.hdr
.ramdisk_image
= initrd_start
;
1671 boot_params
.hdr
.ramdisk_size
= xen_start_info
->mod_len
;
1672 boot_params
.hdr
.cmd_line_ptr
= __pa(xen_start_info
->cmd_line
);
1674 if (!xen_initial_domain()) {
1675 add_preferred_console("xenboot", 0, NULL
);
1676 add_preferred_console("tty", 0, NULL
);
1677 add_preferred_console("hvc", 0, NULL
);
1679 x86_init
.pci
.arch_init
= pci_xen_init
;
1681 const struct dom0_vga_console_info
*info
=
1682 (void *)((char *)xen_start_info
+
1683 xen_start_info
->console
.dom0
.info_off
);
1684 struct xen_platform_op op
= {
1685 .cmd
= XENPF_firmware_info
,
1686 .interface_version
= XENPF_INTERFACE_VERSION
,
1687 .u
.firmware_info
.type
= XEN_FW_KBD_SHIFT_FLAGS
,
1690 xen_init_vga(info
, xen_start_info
->console
.dom0
.info_size
);
1691 xen_start_info
->console
.domU
.mfn
= 0;
1692 xen_start_info
->console
.domU
.evtchn
= 0;
1694 if (HYPERVISOR_platform_op(&op
) == 0)
1695 boot_params
.kbd_status
= op
.u
.firmware_info
.u
.kbd_shift_flags
;
1697 /* Make sure ACS will be enabled */
1700 xen_acpi_sleep_register();
1702 /* Avoid searching for BIOS MP tables */
1703 x86_init
.mpparse
.find_smp_config
= x86_init_noop
;
1704 x86_init
.mpparse
.get_smp_config
= x86_init_uint_noop
;
1706 xen_boot_params_init_edd();
1709 /* PCI BIOS service won't work from a PV guest. */
1710 pci_probe
&= ~PCI_PROBE_BIOS
;
1712 xen_raw_console_write("about to get started...\n");
1714 xen_setup_runstate_info(0);
1718 /* Start the world */
1719 #ifdef CONFIG_X86_32
1720 i386_start_kernel();
1722 cr4_init_shadow(); /* 32b kernel does this in i386_start_kernel() */
1723 x86_64_start_reservations((char *)__pa_symbol(&boot_params
));
1727 void __ref
xen_hvm_init_shared_info(void)
1730 struct xen_add_to_physmap xatp
;
1731 static struct shared_info
*shared_info_page
= 0;
1733 if (!shared_info_page
)
1734 shared_info_page
= (struct shared_info
*)
1735 extend_brk(PAGE_SIZE
, PAGE_SIZE
);
1736 xatp
.domid
= DOMID_SELF
;
1738 xatp
.space
= XENMAPSPACE_shared_info
;
1739 xatp
.gpfn
= __pa(shared_info_page
) >> PAGE_SHIFT
;
1740 if (HYPERVISOR_memory_op(XENMEM_add_to_physmap
, &xatp
))
1743 HYPERVISOR_shared_info
= (struct shared_info
*)shared_info_page
;
1745 /* xen_vcpu is a pointer to the vcpu_info struct in the shared_info
1746 * page, we use it in the event channel upcall and in some pvclock
1747 * related functions. We don't need the vcpu_info placement
1748 * optimizations because we don't use any pv_mmu or pv_irq op on
1750 * When xen_hvm_init_shared_info is run at boot time only vcpu 0 is
1751 * online but xen_hvm_init_shared_info is run at resume time too and
1752 * in that case multiple vcpus might be online. */
1753 for_each_online_cpu(cpu
) {
1754 /* Leave it to be NULL. */
1755 if (cpu
>= MAX_VIRT_CPUS
)
1757 per_cpu(xen_vcpu
, cpu
) = &HYPERVISOR_shared_info
->vcpu_info
[cpu
];
1761 #ifdef CONFIG_XEN_PVHVM
1762 static void __init
init_hvm_pv_info(void)
1765 uint32_t eax
, ebx
, ecx
, edx
, pages
, msr
, base
;
1768 base
= xen_cpuid_base();
1769 cpuid(base
+ 1, &eax
, &ebx
, &ecx
, &edx
);
1772 minor
= eax
& 0xffff;
1773 printk(KERN_INFO
"Xen version %d.%d.\n", major
, minor
);
1775 cpuid(base
+ 2, &pages
, &msr
, &ecx
, &edx
);
1777 pfn
= __pa(hypercall_page
);
1778 wrmsr_safe(msr
, (u32
)pfn
, (u32
)(pfn
>> 32));
1780 xen_setup_features();
1782 pv_info
.name
= "Xen HVM";
1784 xen_domain_type
= XEN_HVM_DOMAIN
;
1787 static int xen_hvm_cpu_notify(struct notifier_block
*self
, unsigned long action
,
1790 int cpu
= (long)hcpu
;
1792 case CPU_UP_PREPARE
:
1793 xen_vcpu_setup(cpu
);
1794 if (xen_have_vector_callback
) {
1795 if (xen_feature(XENFEAT_hvm_safe_pvclock
))
1796 xen_setup_timer(cpu
);
1805 static struct notifier_block xen_hvm_cpu_notifier
= {
1806 .notifier_call
= xen_hvm_cpu_notify
,
1809 #ifdef CONFIG_KEXEC_CORE
1810 static void xen_hvm_shutdown(void)
1812 native_machine_shutdown();
1813 if (kexec_in_progress
)
1814 xen_reboot(SHUTDOWN_soft_reset
);
1817 static void xen_hvm_crash_shutdown(struct pt_regs
*regs
)
1819 native_machine_crash_shutdown(regs
);
1820 xen_reboot(SHUTDOWN_soft_reset
);
1824 static void __init
xen_hvm_guest_init(void)
1826 if (xen_pv_domain())
1831 xen_hvm_init_shared_info();
1833 xen_panic_handler_init();
1835 if (xen_feature(XENFEAT_hvm_callback_vector
))
1836 xen_have_vector_callback
= 1;
1838 register_cpu_notifier(&xen_hvm_cpu_notifier
);
1839 xen_unplug_emulated_devices();
1840 x86_init
.irqs
.intr_init
= xen_init_IRQ
;
1841 xen_hvm_init_time_ops();
1842 xen_hvm_init_mmu_ops();
1843 #ifdef CONFIG_KEXEC_CORE
1844 machine_ops
.shutdown
= xen_hvm_shutdown
;
1845 machine_ops
.crash_shutdown
= xen_hvm_crash_shutdown
;
1850 static bool xen_nopv
= false;
1851 static __init
int xen_parse_nopv(char *arg
)
1856 early_param("xen_nopv", xen_parse_nopv
);
1858 static uint32_t __init
xen_platform(void)
1863 return xen_cpuid_base();
1866 bool xen_hvm_need_lapic(void)
1870 if (xen_pv_domain())
1872 if (!xen_hvm_domain())
1874 if (xen_feature(XENFEAT_hvm_pirqs
) && xen_have_vector_callback
)
1878 EXPORT_SYMBOL_GPL(xen_hvm_need_lapic
);
1880 static void xen_set_cpu_features(struct cpuinfo_x86
*c
)
1882 if (xen_pv_domain()) {
1883 clear_cpu_bug(c
, X86_BUG_SYSRET_SS_ATTRS
);
1884 set_cpu_cap(c
, X86_FEATURE_XENPV
);
1888 const struct hypervisor_x86 x86_hyper_xen
= {
1890 .detect
= xen_platform
,
1891 #ifdef CONFIG_XEN_PVHVM
1892 .init_platform
= xen_hvm_guest_init
,
1894 .x2apic_available
= xen_x2apic_para_available
,
1895 .set_cpu_features
= xen_set_cpu_features
,
1897 EXPORT_SYMBOL(x86_hyper_xen
);
1899 #ifdef CONFIG_HOTPLUG_CPU
1900 void xen_arch_register_cpu(int num
)
1902 arch_register_cpu(num
);
1904 EXPORT_SYMBOL(xen_arch_register_cpu
);
1906 void xen_arch_unregister_cpu(int num
)
1908 arch_unregister_cpu(num
);
1910 EXPORT_SYMBOL(xen_arch_unregister_cpu
);