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-rw-r--r--arch/x86/hyperv/Makefile3
-rw-r--r--arch/x86/hyperv/hv_apic.c256
-rw-r--r--arch/x86/hyperv/hv_init.c32
-rw-r--r--arch/x86/hyperv/mmu.c75
-rw-r--r--arch/x86/include/asm/hyperv-tlfs.h30
-rw-r--r--arch/x86/include/asm/mshyperv.h44
6 files changed, 368 insertions, 72 deletions
diff --git a/arch/x86/hyperv/Makefile b/arch/x86/hyperv/Makefile
index 367a8203cfcf..b173d404e3df 100644
--- a/arch/x86/hyperv/Makefile
+++ b/arch/x86/hyperv/Makefile
@@ -1 +1,2 @@
-obj-y := hv_init.o mmu.o
+obj-y := hv_init.o mmu.o
+obj-$(CONFIG_X86_64) += hv_apic.o
diff --git a/arch/x86/hyperv/hv_apic.c b/arch/x86/hyperv/hv_apic.c
new file mode 100644
index 000000000000..f68855499391
--- /dev/null
+++ b/arch/x86/hyperv/hv_apic.c
@@ -0,0 +1,256 @@
+// SPDX-License-Identifier: GPL-2.0
+
+/*
+ * Hyper-V specific APIC code.
+ *
+ * Copyright (C) 2018, Microsoft, Inc.
+ *
+ * Author : K. Y. Srinivasan <kys@microsoft.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published
+ * by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
+ * NON INFRINGEMENT. See the GNU General Public License for more
+ * details.
+ *
+ */
+
+#include <linux/types.h>
+#include <linux/version.h>
+#include <linux/vmalloc.h>
+#include <linux/mm.h>
+#include <linux/clockchips.h>
+#include <linux/hyperv.h>
+#include <linux/slab.h>
+#include <linux/cpuhotplug.h>
+#include <asm/hypervisor.h>
+#include <asm/mshyperv.h>
+#include <asm/apic.h>
+
+static struct apic orig_apic;
+
+static u64 hv_apic_icr_read(void)
+{
+ u64 reg_val;
+
+ rdmsrl(HV_X64_MSR_ICR, reg_val);
+ return reg_val;
+}
+
+static void hv_apic_icr_write(u32 low, u32 id)
+{
+ u64 reg_val;
+
+ reg_val = SET_APIC_DEST_FIELD(id);
+ reg_val = reg_val << 32;
+ reg_val |= low;
+
+ wrmsrl(HV_X64_MSR_ICR, reg_val);
+}
+
+static u32 hv_apic_read(u32 reg)
+{
+ u32 reg_val, hi;
+
+ switch (reg) {
+ case APIC_EOI:
+ rdmsr(HV_X64_MSR_EOI, reg_val, hi);
+ return reg_val;
+ case APIC_TASKPRI:
+ rdmsr(HV_X64_MSR_TPR, reg_val, hi);
+ return reg_val;
+
+ default:
+ return native_apic_mem_read(reg);
+ }
+}
+
+static void hv_apic_write(u32 reg, u32 val)
+{
+ switch (reg) {
+ case APIC_EOI:
+ wrmsr(HV_X64_MSR_EOI, val, 0);
+ break;
+ case APIC_TASKPRI:
+ wrmsr(HV_X64_MSR_TPR, val, 0);
+ break;
+ default:
+ native_apic_mem_write(reg, val);
+ }
+}
+
+static void hv_apic_eoi_write(u32 reg, u32 val)
+{
+ wrmsr(HV_X64_MSR_EOI, val, 0);
+}
+
+/*
+ * IPI implementation on Hyper-V.
+ */
+static bool __send_ipi_mask_ex(const struct cpumask *mask, int vector)
+{
+ struct ipi_arg_ex **arg;
+ struct ipi_arg_ex *ipi_arg;
+ unsigned long flags;
+ int nr_bank = 0;
+ int ret = 1;
+
+ local_irq_save(flags);
+ arg = (struct ipi_arg_ex **)this_cpu_ptr(hyperv_pcpu_input_arg);
+
+ ipi_arg = *arg;
+ if (unlikely(!ipi_arg))
+ goto ipi_mask_ex_done;
+
+ ipi_arg->vector = vector;
+ ipi_arg->reserved = 0;
+ ipi_arg->vp_set.valid_bank_mask = 0;
+
+ if (!cpumask_equal(mask, cpu_present_mask)) {
+ ipi_arg->vp_set.format = HV_GENERIC_SET_SPARSE_4K;
+ nr_bank = cpumask_to_vpset(&(ipi_arg->vp_set), mask);
+ }
+ if (!nr_bank)
+ ipi_arg->vp_set.format = HV_GENERIC_SET_ALL;
+
+ ret = hv_do_rep_hypercall(HVCALL_SEND_IPI_EX, 0, nr_bank,
+ ipi_arg, NULL);
+
+ipi_mask_ex_done:
+ local_irq_restore(flags);
+ return ((ret == 0) ? true : false);
+}
+
+static bool __send_ipi_mask(const struct cpumask *mask, int vector)
+{
+ int cur_cpu, vcpu;
+ struct ipi_arg_non_ex **arg;
+ struct ipi_arg_non_ex *ipi_arg;
+ int ret = 1;
+ unsigned long flags;
+
+ if (cpumask_empty(mask))
+ return true;
+
+ if (!hv_hypercall_pg)
+ return false;
+
+ if ((vector < HV_IPI_LOW_VECTOR) || (vector > HV_IPI_HIGH_VECTOR))
+ return false;
+
+ if ((ms_hyperv.hints & HV_X64_EX_PROCESSOR_MASKS_RECOMMENDED))
+ return __send_ipi_mask_ex(mask, vector);
+
+ local_irq_save(flags);
+ arg = (struct ipi_arg_non_ex **)this_cpu_ptr(hyperv_pcpu_input_arg);
+
+ ipi_arg = *arg;
+ if (unlikely(!ipi_arg))
+ goto ipi_mask_done;
+
+ ipi_arg->vector = vector;
+ ipi_arg->reserved = 0;
+ ipi_arg->cpu_mask = 0;
+
+ for_each_cpu(cur_cpu, mask) {
+ vcpu = hv_cpu_number_to_vp_number(cur_cpu);
+ /*
+ * This particular version of the IPI hypercall can
+ * only target upto 64 CPUs.
+ */
+ if (vcpu >= 64)
+ goto ipi_mask_done;
+
+ __set_bit(vcpu, (unsigned long *)&ipi_arg->cpu_mask);
+ }
+
+ ret = hv_do_hypercall(HVCALL_SEND_IPI, ipi_arg, NULL);
+
+ipi_mask_done:
+ local_irq_restore(flags);
+ return ((ret == 0) ? true : false);
+}
+
+static bool __send_ipi_one(int cpu, int vector)
+{
+ struct cpumask mask = CPU_MASK_NONE;
+
+ cpumask_set_cpu(cpu, &mask);
+ return __send_ipi_mask(&mask, vector);
+}
+
+static void hv_send_ipi(int cpu, int vector)
+{
+ if (!__send_ipi_one(cpu, vector))
+ orig_apic.send_IPI(cpu, vector);
+}
+
+static void hv_send_ipi_mask(const struct cpumask *mask, int vector)
+{
+ if (!__send_ipi_mask(mask, vector))
+ orig_apic.send_IPI_mask(mask, vector);
+}
+
+static void hv_send_ipi_mask_allbutself(const struct cpumask *mask, int vector)
+{
+ unsigned int this_cpu = smp_processor_id();
+ struct cpumask new_mask;
+ const struct cpumask *local_mask;
+
+ cpumask_copy(&new_mask, mask);
+ cpumask_clear_cpu(this_cpu, &new_mask);
+ local_mask = &new_mask;
+ if (!__send_ipi_mask(local_mask, vector))
+ orig_apic.send_IPI_mask_allbutself(mask, vector);
+}
+
+static void hv_send_ipi_allbutself(int vector)
+{
+ hv_send_ipi_mask_allbutself(cpu_online_mask, vector);
+}
+
+static void hv_send_ipi_all(int vector)
+{
+ if (!__send_ipi_mask(cpu_online_mask, vector))
+ orig_apic.send_IPI_all(vector);
+}
+
+static void hv_send_ipi_self(int vector)
+{
+ if (!__send_ipi_one(smp_processor_id(), vector))
+ orig_apic.send_IPI_self(vector);
+}
+
+void __init hv_apic_init(void)
+{
+ if (ms_hyperv.hints & HV_X64_CLUSTER_IPI_RECOMMENDED) {
+ if ((ms_hyperv.hints & HV_X64_EX_PROCESSOR_MASKS_RECOMMENDED))
+ pr_info("Hyper-V: Using ext hypercalls for IPI\n");
+ else
+ pr_info("Hyper-V: Using IPI hypercalls\n");
+ /*
+ * Set the IPI entry points.
+ */
+ orig_apic = *apic;
+
+ apic->send_IPI = hv_send_ipi;
+ apic->send_IPI_mask = hv_send_ipi_mask;
+ apic->send_IPI_mask_allbutself = hv_send_ipi_mask_allbutself;
+ apic->send_IPI_allbutself = hv_send_ipi_allbutself;
+ apic->send_IPI_all = hv_send_ipi_all;
+ apic->send_IPI_self = hv_send_ipi_self;
+ }
+
+ if (ms_hyperv.hints & HV_X64_APIC_ACCESS_RECOMMENDED) {
+ pr_info("Hyper-V: Using MSR based APIC access\n");
+ apic_set_eoi_write(hv_apic_eoi_write);
+ apic->read = hv_apic_read;
+ apic->write = hv_apic_write;
+ apic->icr_write = hv_apic_icr_write;
+ apic->icr_read = hv_apic_icr_read;
+ }
+}
diff --git a/arch/x86/hyperv/hv_init.c b/arch/x86/hyperv/hv_init.c
index cfecc2272f2d..4c431e1c1eff 100644
--- a/arch/x86/hyperv/hv_init.c
+++ b/arch/x86/hyperv/hv_init.c
@@ -91,12 +91,19 @@ EXPORT_SYMBOL_GPL(hv_vp_index);
struct hv_vp_assist_page **hv_vp_assist_page;
EXPORT_SYMBOL_GPL(hv_vp_assist_page);
+void __percpu **hyperv_pcpu_input_arg;
+EXPORT_SYMBOL_GPL(hyperv_pcpu_input_arg);
+
u32 hv_max_vp_index;
static int hv_cpu_init(unsigned int cpu)
{
u64 msr_vp_index;
struct hv_vp_assist_page **hvp = &hv_vp_assist_page[smp_processor_id()];
+ void **input_arg;
+
+ input_arg = (void **)this_cpu_ptr(hyperv_pcpu_input_arg);
+ *input_arg = page_address(alloc_page(GFP_KERNEL));
hv_get_vp_index(msr_vp_index);
@@ -217,6 +224,16 @@ static int hv_cpu_die(unsigned int cpu)
{
struct hv_reenlightenment_control re_ctrl;
unsigned int new_cpu;
+ unsigned long flags;
+ void **input_arg;
+ void *input_pg = NULL;
+
+ local_irq_save(flags);
+ input_arg = (void **)this_cpu_ptr(hyperv_pcpu_input_arg);
+ input_pg = *input_arg;
+ *input_arg = NULL;
+ local_irq_restore(flags);
+ free_page((unsigned long)input_pg);
if (hv_vp_assist_page && hv_vp_assist_page[cpu])
wrmsrl(HV_X64_MSR_VP_ASSIST_PAGE, 0);
@@ -242,8 +259,9 @@ static int hv_cpu_die(unsigned int cpu)
*
* 1. Setup the hypercall page.
* 2. Register Hyper-V specific clocksource.
+ * 3. Setup Hyper-V specific APIC entry points.
*/
-void hyperv_init(void)
+void __init hyperv_init(void)
{
u64 guest_id, required_msrs;
union hv_x64_msr_hypercall_contents hypercall_msr;
@@ -259,6 +277,16 @@ void hyperv_init(void)
if ((ms_hyperv.features & required_msrs) != required_msrs)
return;
+ /*
+ * Allocate the per-CPU state for the hypercall input arg.
+ * If this allocation fails, we will not be able to setup
+ * (per-CPU) hypercall input page and thus this failure is
+ * fatal on Hyper-V.
+ */
+ hyperv_pcpu_input_arg = alloc_percpu(void *);
+
+ BUG_ON(hyperv_pcpu_input_arg == NULL);
+
/* Allocate percpu VP index */
hv_vp_index = kmalloc_array(num_possible_cpus(), sizeof(*hv_vp_index),
GFP_KERNEL);
@@ -296,7 +324,7 @@ void hyperv_init(void)
hypercall_msr.guest_physical_address = vmalloc_to_pfn(hv_hypercall_pg);
wrmsrl(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64);
- hyper_alloc_mmu();
+ hv_apic_init();
/*
* Register Hyper-V specific clocksource.
diff --git a/arch/x86/hyperv/mmu.c b/arch/x86/hyperv/mmu.c
index 56c9ebac946f..5f053d7d1bd9 100644
--- a/arch/x86/hyperv/mmu.c
+++ b/arch/x86/hyperv/mmu.c
@@ -25,20 +25,13 @@ struct hv_flush_pcpu {
struct hv_flush_pcpu_ex {
u64 address_space;
u64 flags;
- struct {
- u64 format;
- u64 valid_bank_mask;
- u64 bank_contents[];
- } hv_vp_set;
+ struct hv_vpset hv_vp_set;
u64 gva_list[];
};
/* Each gva in gva_list encodes up to 4096 pages to flush */
#define HV_TLB_FLUSH_UNIT (4096 * PAGE_SIZE)
-static struct hv_flush_pcpu __percpu **pcpu_flush;
-
-static struct hv_flush_pcpu_ex __percpu **pcpu_flush_ex;
/*
* Fills in gva_list starting from offset. Returns the number of items added.
@@ -70,41 +63,6 @@ static inline int fill_gva_list(u64 gva_list[], int offset,
return gva_n - offset;
}
-/* Return the number of banks in the resulting vp_set */
-static inline int cpumask_to_vp_set(struct hv_flush_pcpu_ex *flush,
- const struct cpumask *cpus)
-{
- int cpu, vcpu, vcpu_bank, vcpu_offset, nr_bank = 1;
-
- /* valid_bank_mask can represent up to 64 banks */
- if (hv_max_vp_index / 64 >= 64)
- return 0;
-
- /*
- * Clear all banks up to the maximum possible bank as hv_flush_pcpu_ex
- * structs are not cleared between calls, we risk flushing unneeded
- * vCPUs otherwise.
- */
- for (vcpu_bank = 0; vcpu_bank <= hv_max_vp_index / 64; vcpu_bank++)
- flush->hv_vp_set.bank_contents[vcpu_bank] = 0;
-
- /*
- * Some banks may end up being empty but this is acceptable.
- */
- for_each_cpu(cpu, cpus) {
- vcpu = hv_cpu_number_to_vp_number(cpu);
- vcpu_bank = vcpu / 64;
- vcpu_offset = vcpu % 64;
- __set_bit(vcpu_offset, (unsigned long *)
- &flush->hv_vp_set.bank_contents[vcpu_bank]);
- if (vcpu_bank >= nr_bank)
- nr_bank = vcpu_bank + 1;
- }
- flush->hv_vp_set.valid_bank_mask = GENMASK_ULL(nr_bank - 1, 0);
-
- return nr_bank;
-}
-
static void hyperv_flush_tlb_others(const struct cpumask *cpus,
const struct flush_tlb_info *info)
{
@@ -116,7 +74,7 @@ static void hyperv_flush_tlb_others(const struct cpumask *cpus,
trace_hyperv_mmu_flush_tlb_others(cpus, info);
- if (!pcpu_flush || !hv_hypercall_pg)
+ if (!hv_hypercall_pg)
goto do_native;
if (cpumask_empty(cpus))
@@ -124,10 +82,8 @@ static void hyperv_flush_tlb_others(const struct cpumask *cpus,
local_irq_save(flags);
- flush_pcpu = this_cpu_ptr(pcpu_flush);
-
- if (unlikely(!*flush_pcpu))
- *flush_pcpu = page_address(alloc_page(GFP_ATOMIC));
+ flush_pcpu = (struct hv_flush_pcpu **)
+ this_cpu_ptr(hyperv_pcpu_input_arg);
flush = *flush_pcpu;
@@ -203,7 +159,7 @@ static void hyperv_flush_tlb_others_ex(const struct cpumask *cpus,
trace_hyperv_mmu_flush_tlb_others(cpus, info);
- if (!pcpu_flush_ex || !hv_hypercall_pg)
+ if (!hv_hypercall_pg)
goto do_native;
if (cpumask_empty(cpus))
@@ -211,10 +167,8 @@ static void hyperv_flush_tlb_others_ex(const struct cpumask *cpus,
local_irq_save(flags);
- flush_pcpu = this_cpu_ptr(pcpu_flush_ex);
-
- if (unlikely(!*flush_pcpu))
- *flush_pcpu = page_address(alloc_page(GFP_ATOMIC));
+ flush_pcpu = (struct hv_flush_pcpu_ex **)
+ this_cpu_ptr(hyperv_pcpu_input_arg);
flush = *flush_pcpu;
@@ -239,8 +193,8 @@ static void hyperv_flush_tlb_others_ex(const struct cpumask *cpus,
flush->hv_vp_set.valid_bank_mask = 0;
if (!cpumask_equal(cpus, cpu_present_mask)) {
- flush->hv_vp_set.format = HV_GENERIC_SET_SPARCE_4K;
- nr_bank = cpumask_to_vp_set(flush, cpus);
+ flush->hv_vp_set.format = HV_GENERIC_SET_SPARSE_4K;
+ nr_bank = cpumask_to_vpset(&(flush->hv_vp_set), cpus);
}
if (!nr_bank) {
@@ -296,14 +250,3 @@ void hyperv_setup_mmu_ops(void)
pv_mmu_ops.flush_tlb_others = hyperv_flush_tlb_others_ex;
}
}
-
-void hyper_alloc_mmu(void)
-{
- if (!(ms_hyperv.hints & HV_X64_REMOTE_TLB_FLUSH_RECOMMENDED))
- return;
-
- if (!(ms_hyperv.hints & HV_X64_EX_PROCESSOR_MASKS_RECOMMENDED))
- pcpu_flush = alloc_percpu(struct hv_flush_pcpu *);
- else
- pcpu_flush_ex = alloc_percpu(struct hv_flush_pcpu_ex *);
-}
diff --git a/arch/x86/include/asm/hyperv-tlfs.h b/arch/x86/include/asm/hyperv-tlfs.h
index 416cb0e0c496..3bfa92c2793c 100644
--- a/arch/x86/include/asm/hyperv-tlfs.h
+++ b/arch/x86/include/asm/hyperv-tlfs.h
@@ -164,6 +164,11 @@
*/
#define HV_X64_DEPRECATING_AEOI_RECOMMENDED (1 << 9)
+/*
+ * Recommend using cluster IPI hypercalls.
+ */
+#define HV_X64_CLUSTER_IPI_RECOMMENDED (1 << 10)
+
/* Recommend using the newer ExProcessorMasks interface */
#define HV_X64_EX_PROCESSOR_MASKS_RECOMMENDED (1 << 11)
@@ -329,12 +334,17 @@ struct hv_tsc_emulation_status {
#define HV_X64_MSR_HYPERCALL_PAGE_ADDRESS_MASK \
(~((1ull << HV_X64_MSR_HYPERCALL_PAGE_ADDRESS_SHIFT) - 1))
+#define HV_IPI_LOW_VECTOR 0x10
+#define HV_IPI_HIGH_VECTOR 0xff
+
/* Declare the various hypercall operations. */
#define HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE 0x0002
#define HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST 0x0003
#define HVCALL_NOTIFY_LONG_SPIN_WAIT 0x0008
+#define HVCALL_SEND_IPI 0x000b
#define HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE_EX 0x0013
#define HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST_EX 0x0014
+#define HVCALL_SEND_IPI_EX 0x0015
#define HVCALL_POST_MESSAGE 0x005c
#define HVCALL_SIGNAL_EVENT 0x005d
@@ -360,7 +370,7 @@ struct hv_tsc_emulation_status {
#define HV_FLUSH_USE_EXTENDED_RANGE_FORMAT BIT(3)
enum HV_GENERIC_SET_FORMAT {
- HV_GENERIC_SET_SPARCE_4K,
+ HV_GENERIC_SET_SPARSE_4K,
HV_GENERIC_SET_ALL,
};
@@ -706,4 +716,22 @@ struct hv_enlightened_vmcs {
#define HV_STIMER_AUTOENABLE (1ULL << 3)
#define HV_STIMER_SINT(config) (__u8)(((config) >> 16) & 0x0F)
+struct ipi_arg_non_ex {
+ u32 vector;
+ u32 reserved;
+ u64 cpu_mask;
+};
+
+struct hv_vpset {
+ u64 format;
+ u64 valid_bank_mask;
+ u64 bank_contents[];
+};
+
+struct ipi_arg_ex {
+ u32 vector;
+ u32 reserved;
+ struct hv_vpset vp_set;
+};
+
#endif
diff --git a/arch/x86/include/asm/mshyperv.h b/arch/x86/include/asm/mshyperv.h
index b90e79610cf7..997192131b7b 100644
--- a/arch/x86/include/asm/mshyperv.h
+++ b/arch/x86/include/asm/mshyperv.h
@@ -122,6 +122,7 @@ static inline void hv_disable_stimer0_percpu_irq(int irq) {}
#if IS_ENABLED(CONFIG_HYPERV)
extern struct clocksource *hyperv_cs;
extern void *hv_hypercall_pg;
+extern void __percpu **hyperv_pcpu_input_arg;
static inline u64 hv_do_hypercall(u64 control, void *input, void *output)
{
@@ -258,9 +259,41 @@ static inline int hv_cpu_number_to_vp_number(int cpu_number)
return hv_vp_index[cpu_number];
}
-void hyperv_init(void);
+static inline int cpumask_to_vpset(struct hv_vpset *vpset,
+ const struct cpumask *cpus)
+{
+ int cpu, vcpu, vcpu_bank, vcpu_offset, nr_bank = 1;
+
+ /* valid_bank_mask can represent up to 64 banks */
+ if (hv_max_vp_index / 64 >= 64)
+ return 0;
+
+ /*
+ * Clear all banks up to the maximum possible bank as hv_flush_pcpu_ex
+ * structs are not cleared between calls, we risk flushing unneeded
+ * vCPUs otherwise.
+ */
+ for (vcpu_bank = 0; vcpu_bank <= hv_max_vp_index / 64; vcpu_bank++)
+ vpset->bank_contents[vcpu_bank] = 0;
+
+ /*
+ * Some banks may end up being empty but this is acceptable.
+ */
+ for_each_cpu(cpu, cpus) {
+ vcpu = hv_cpu_number_to_vp_number(cpu);
+ vcpu_bank = vcpu / 64;
+ vcpu_offset = vcpu % 64;
+ __set_bit(vcpu_offset, (unsigned long *)
+ &vpset->bank_contents[vcpu_bank]);
+ if (vcpu_bank >= nr_bank)
+ nr_bank = vcpu_bank + 1;
+ }
+ vpset->valid_bank_mask = GENMASK_ULL(nr_bank - 1, 0);
+ return nr_bank;
+}
+
+void __init hyperv_init(void);
void hyperv_setup_mmu_ops(void);
-void hyper_alloc_mmu(void);
void hyperv_report_panic(struct pt_regs *regs, long err);
bool hv_is_hyperv_initialized(void);
void hyperv_cleanup(void);
@@ -269,6 +302,13 @@ void hyperv_reenlightenment_intr(struct pt_regs *regs);
void set_hv_tscchange_cb(void (*cb)(void));
void clear_hv_tscchange_cb(void);
void hyperv_stop_tsc_emulation(void);
+
+#ifdef CONFIG_X86_64
+void hv_apic_init(void);
+#else
+static inline void hv_apic_init(void) {}
+#endif
+
#else /* CONFIG_HYPERV */
static inline void hyperv_init(void) {}
static inline bool hv_is_hyperv_initialized(void) { return false; }