| Message ID | 1626793023-13830-4-git-send-email-mikelley@microsoft.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Enable Linux guests on Hyper-V on ARM64 | expand |
On Tue, Jul 20, 2021 at 07:57:01AM -0700, Michael Kelley wrote: > Add ARM64-specific code to initialize the Hyper-V > hypervisor when booting as a guest VM. > > This code is built only when CONFIG_HYPERV is enabled. > > Signed-off-by: Michael Kelley <mikelley@microsoft.com> FWIW, Reviewed-by: Boqun Feng <boqun.feng@gmail.com> Regards, Boqun > --- > arch/arm64/hyperv/Makefile | 2 +- > arch/arm64/hyperv/mshyperv.c | 83 ++++++++++++++++++++++++++++++++++++++++++++ > 2 files changed, 84 insertions(+), 1 deletion(-) > create mode 100644 arch/arm64/hyperv/mshyperv.c > > diff --git a/arch/arm64/hyperv/Makefile b/arch/arm64/hyperv/Makefile > index 1697d30..87c31c0 100644 > --- a/arch/arm64/hyperv/Makefile > +++ b/arch/arm64/hyperv/Makefile > @@ -1,2 +1,2 @@ > # SPDX-License-Identifier: GPL-2.0 > -obj-y := hv_core.o > +obj-y := hv_core.o mshyperv.o > diff --git a/arch/arm64/hyperv/mshyperv.c b/arch/arm64/hyperv/mshyperv.c > new file mode 100644 > index 0000000..2811fd0 > --- /dev/null > +++ b/arch/arm64/hyperv/mshyperv.c > @@ -0,0 +1,83 @@ > +// SPDX-License-Identifier: GPL-2.0 > + > +/* > + * Core routines for interacting with Microsoft's Hyper-V hypervisor, > + * including hypervisor initialization. > + * > + * Copyright (C) 2021, Microsoft, Inc. > + * > + * Author : Michael Kelley <mikelley@microsoft.com> > + */ > + > +#include <linux/types.h> > +#include <linux/acpi.h> > +#include <linux/export.h> > +#include <linux/errno.h> > +#include <linux/version.h> > +#include <linux/cpuhotplug.h> > +#include <asm/mshyperv.h> > + > +static bool hyperv_initialized; > + > +static int __init hyperv_init(void) > +{ > + struct hv_get_vp_registers_output result; > + u32 a, b, c, d; > + u64 guest_id; > + int ret; > + > + /* > + * If we're in a VM on Hyper-V, the ACPI hypervisor_id field will > + * have the string "MsHyperV". > + */ > + if (strncmp((char *)&acpi_gbl_FADT.hypervisor_id, "MsHyperV", 8)) > + return -EINVAL; > + > + /* Setup the guest ID */ > + guest_id = generate_guest_id(0, LINUX_VERSION_CODE, 0); > + hv_set_vpreg(HV_REGISTER_GUEST_OSID, guest_id); > + > + /* Get the features and hints from Hyper-V */ > + hv_get_vpreg_128(HV_REGISTER_FEATURES, &result); > + ms_hyperv.features = result.as32.a; > + ms_hyperv.priv_high = result.as32.b; > + ms_hyperv.misc_features = result.as32.c; > + > + hv_get_vpreg_128(HV_REGISTER_ENLIGHTENMENTS, &result); > + ms_hyperv.hints = result.as32.a; > + > + pr_info("Hyper-V: privilege flags low 0x%x, high 0x%x, hints 0x%x, misc 0x%x\n", > + ms_hyperv.features, ms_hyperv.priv_high, ms_hyperv.hints, > + ms_hyperv.misc_features); > + > + /* Get information about the Hyper-V host version */ > + hv_get_vpreg_128(HV_REGISTER_HYPERVISOR_VERSION, &result); > + a = result.as32.a; > + b = result.as32.b; > + c = result.as32.c; > + d = result.as32.d; > + pr_info("Hyper-V: Host Build %d.%d.%d.%d-%d-%d\n", > + b >> 16, b & 0xFFFF, a, d & 0xFFFFFF, c, d >> 24); > + > + ret = hv_common_init(); > + if (ret) > + return ret; > + > + ret = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "arm64/hyperv_init:online", > + hv_common_cpu_init, hv_common_cpu_die); > + if (ret < 0) { > + hv_common_free(); > + return ret; > + } > + > + hyperv_initialized = true; > + return 0; > +} > + > +early_initcall(hyperv_init); > + > +bool hv_is_hyperv_initialized(void) > +{ > + return hyperv_initialized; > +} > +EXPORT_SYMBOL_GPL(hv_is_hyperv_initialized); > -- > 1.8.3.1 >
> Subject: [PATCH v11 3/5] arm64: hyperv: Initialize hypervisor on boot > > Add ARM64-specific code to initialize the Hyper-V > hypervisor when booting as a guest VM. > > This code is built only when CONFIG_HYPERV is enabled. > > Signed-off-by: Michael Kelley <mikelley@microsoft.com> > --- > arch/arm64/hyperv/Makefile | 2 +- > arch/arm64/hyperv/mshyperv.c | 83 ++++++++++++++++++++++++++++++++++++++++++++ > 2 files changed, 84 insertions(+), 1 deletion(-) > create mode 100644 arch/arm64/hyperv/mshyperv.c > > diff --git a/arch/arm64/hyperv/Makefile b/arch/arm64/hyperv/Makefile > index 1697d30..87c31c0 100644 > --- a/arch/arm64/hyperv/Makefile > +++ b/arch/arm64/hyperv/Makefile > @@ -1,2 +1,2 @@ > # SPDX-License-Identifier: GPL-2.0 > -obj-y := hv_core.o > +obj-y := hv_core.o mshyperv.o > diff --git a/arch/arm64/hyperv/mshyperv.c b/arch/arm64/hyperv/mshyperv.c > new file mode 100644 > index 0000000..2811fd0 > --- /dev/null > +++ b/arch/arm64/hyperv/mshyperv.c > @@ -0,0 +1,83 @@ > +// SPDX-License-Identifier: GPL-2.0 > + > +/* > + * Core routines for interacting with Microsoft's Hyper-V hypervisor, > + * including hypervisor initialization. > + * > + * Copyright (C) 2021, Microsoft, Inc. > + * > + * Author : Michael Kelley <mikelley@microsoft.com> > + */ > + > +#include <linux/types.h> > +#include <linux/acpi.h> > +#include <linux/export.h> > +#include <linux/errno.h> > +#include <linux/version.h> > +#include <linux/cpuhotplug.h> > +#include <asm/mshyperv.h> > + > +static bool hyperv_initialized; > + > +static int __init hyperv_init(void) > +{ > + struct hv_get_vp_registers_output result; > + u32 a, b, c, d; > + u64 guest_id; > + int ret; > + > + /* > + * If we're in a VM on Hyper-V, the ACPI hypervisor_id field will > + * have the string "MsHyperV". > + */ > + if (strncmp((char *)&acpi_gbl_FADT.hypervisor_id, "MsHyperV", 8)) > + return -EINVAL; > + > + /* Setup the guest ID */ > + guest_id = generate_guest_id(0, LINUX_VERSION_CODE, 0); > + hv_set_vpreg(HV_REGISTER_GUEST_OSID, guest_id); > + > + /* Get the features and hints from Hyper-V */ > + hv_get_vpreg_128(HV_REGISTER_FEATURES, &result); > + ms_hyperv.features = result.as32.a; > + ms_hyperv.priv_high = result.as32.b; > + ms_hyperv.misc_features = result.as32.c; > + > + hv_get_vpreg_128(HV_REGISTER_ENLIGHTENMENTS, &result); > + ms_hyperv.hints = result.as32.a; > + > + pr_info("Hyper-V: privilege flags low 0x%x, high 0x%x, hints 0x%x, misc 0x%x\n", > + ms_hyperv.features, ms_hyperv.priv_high, ms_hyperv.hints, > + ms_hyperv.misc_features); > + > + /* Get information about the Hyper-V host version */ > + hv_get_vpreg_128(HV_REGISTER_HYPERVISOR_VERSION, &result); > + a = result.as32.a; > + b = result.as32.b; > + c = result.as32.c; > + d = result.as32.d; > + pr_info("Hyper-V: Host Build %d.%d.%d.%d-%d-%d\n", > + b >> 16, b & 0xFFFF, a, d & 0xFFFFFF, c, d >> 24); > + > + ret = hv_common_init(); > + if (ret) > + return ret; > + > + ret = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "arm64/hyperv_init:online", > + hv_common_cpu_init, hv_common_cpu_die); > + if (ret < 0) { > + hv_common_free(); > + return ret; > + } > + > + hyperv_initialized = true; > + return 0; > +} > + > +early_initcall(hyperv_init); > + > +bool hv_is_hyperv_initialized(void) > +{ > + return hyperv_initialized; > +} > +EXPORT_SYMBOL_GPL(hv_is_hyperv_initialized); > -- > 1.8.3.1 Reviewed-by: Sunil Muthuswamy <sunilmut@microsoft.com>
On Tue, 20 Jul 2021 15:57:01 +0100, Michael Kelley <mikelley@microsoft.com> wrote: > > Add ARM64-specific code to initialize the Hyper-V > hypervisor when booting as a guest VM. > > This code is built only when CONFIG_HYPERV is enabled. > > Signed-off-by: Michael Kelley <mikelley@microsoft.com> > --- > arch/arm64/hyperv/Makefile | 2 +- > arch/arm64/hyperv/mshyperv.c | 83 ++++++++++++++++++++++++++++++++++++++++++++ > 2 files changed, 84 insertions(+), 1 deletion(-) > create mode 100644 arch/arm64/hyperv/mshyperv.c > > diff --git a/arch/arm64/hyperv/Makefile b/arch/arm64/hyperv/Makefile > index 1697d30..87c31c0 100644 > --- a/arch/arm64/hyperv/Makefile > +++ b/arch/arm64/hyperv/Makefile > @@ -1,2 +1,2 @@ > # SPDX-License-Identifier: GPL-2.0 > -obj-y := hv_core.o > +obj-y := hv_core.o mshyperv.o > diff --git a/arch/arm64/hyperv/mshyperv.c b/arch/arm64/hyperv/mshyperv.c > new file mode 100644 > index 0000000..2811fd0 > --- /dev/null > +++ b/arch/arm64/hyperv/mshyperv.c > @@ -0,0 +1,83 @@ > +// SPDX-License-Identifier: GPL-2.0 > + > +/* > + * Core routines for interacting with Microsoft's Hyper-V hypervisor, > + * including hypervisor initialization. > + * > + * Copyright (C) 2021, Microsoft, Inc. > + * > + * Author : Michael Kelley <mikelley@microsoft.com> > + */ > + > +#include <linux/types.h> > +#include <linux/acpi.h> > +#include <linux/export.h> > +#include <linux/errno.h> > +#include <linux/version.h> > +#include <linux/cpuhotplug.h> > +#include <asm/mshyperv.h> > + > +static bool hyperv_initialized; > + > +static int __init hyperv_init(void) > +{ > + struct hv_get_vp_registers_output result; > + u32 a, b, c, d; > + u64 guest_id; > + int ret; > + > + /* > + * If we're in a VM on Hyper-V, the ACPI hypervisor_id field will > + * have the string "MsHyperV". > + */ > + if (strncmp((char *)&acpi_gbl_FADT.hypervisor_id, "MsHyperV", 8)) > + return -EINVAL; Before going ahead and parsing the local FADT copy, it would be prudent to test that you are actually on an ACPI system, specially given that this function is unconditionally called, even on DT systems. In the same vein, returning -EINVAL when failing to find Hyper-V is a bit excessive. > + > + /* Setup the guest ID */ > + guest_id = generate_guest_id(0, LINUX_VERSION_CODE, 0); > + hv_set_vpreg(HV_REGISTER_GUEST_OSID, guest_id); > + > + /* Get the features and hints from Hyper-V */ > + hv_get_vpreg_128(HV_REGISTER_FEATURES, &result); > + ms_hyperv.features = result.as32.a; > + ms_hyperv.priv_high = result.as32.b; > + ms_hyperv.misc_features = result.as32.c; > + > + hv_get_vpreg_128(HV_REGISTER_ENLIGHTENMENTS, &result); > + ms_hyperv.hints = result.as32.a; > + > + pr_info("Hyper-V: privilege flags low 0x%x, high 0x%x, hints 0x%x, misc 0x%x\n", > + ms_hyperv.features, ms_hyperv.priv_high, ms_hyperv.hints, > + ms_hyperv.misc_features); > + > + /* Get information about the Hyper-V host version */ > + hv_get_vpreg_128(HV_REGISTER_HYPERVISOR_VERSION, &result); > + a = result.as32.a; > + b = result.as32.b; > + c = result.as32.c; > + d = result.as32.d; > + pr_info("Hyper-V: Host Build %d.%d.%d.%d-%d-%d\n", > + b >> 16, b & 0xFFFF, a, d & 0xFFFFFF, c, d >> 24); > + > + ret = hv_common_init(); > + if (ret) > + return ret; > + > + ret = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "arm64/hyperv_init:online", > + hv_common_cpu_init, hv_common_cpu_die); > + if (ret < 0) { > + hv_common_free(); > + return ret; > + } > + > + hyperv_initialized = true; > + return 0; > +} > + > +early_initcall(hyperv_init); > + > +bool hv_is_hyperv_initialized(void) > +{ > + return hyperv_initialized; > +} > +EXPORT_SYMBOL_GPL(hv_is_hyperv_initialized); Thanks, M.
On Tue, Jul 20, 2021 at 07:57:01AM -0700, Michael Kelley wrote: > Add ARM64-specific code to initialize the Hyper-V > hypervisor when booting as a guest VM. > > This code is built only when CONFIG_HYPERV is enabled. > > Signed-off-by: Michael Kelley <mikelley@microsoft.com> > --- > arch/arm64/hyperv/Makefile | 2 +- > arch/arm64/hyperv/mshyperv.c | 83 ++++++++++++++++++++++++++++++++++++++++++++ > 2 files changed, 84 insertions(+), 1 deletion(-) > create mode 100644 arch/arm64/hyperv/mshyperv.c > > diff --git a/arch/arm64/hyperv/Makefile b/arch/arm64/hyperv/Makefile > index 1697d30..87c31c0 100644 > --- a/arch/arm64/hyperv/Makefile > +++ b/arch/arm64/hyperv/Makefile > @@ -1,2 +1,2 @@ > # SPDX-License-Identifier: GPL-2.0 > -obj-y := hv_core.o > +obj-y := hv_core.o mshyperv.o > diff --git a/arch/arm64/hyperv/mshyperv.c b/arch/arm64/hyperv/mshyperv.c > new file mode 100644 > index 0000000..2811fd0 > --- /dev/null > +++ b/arch/arm64/hyperv/mshyperv.c > @@ -0,0 +1,83 @@ > +// SPDX-License-Identifier: GPL-2.0 > + > +/* > + * Core routines for interacting with Microsoft's Hyper-V hypervisor, > + * including hypervisor initialization. > + * > + * Copyright (C) 2021, Microsoft, Inc. > + * > + * Author : Michael Kelley <mikelley@microsoft.com> > + */ > + > +#include <linux/types.h> > +#include <linux/acpi.h> > +#include <linux/export.h> > +#include <linux/errno.h> > +#include <linux/version.h> > +#include <linux/cpuhotplug.h> > +#include <asm/mshyperv.h> > + > +static bool hyperv_initialized; > + > +static int __init hyperv_init(void) > +{ > + struct hv_get_vp_registers_output result; > + u32 a, b, c, d; > + u64 guest_id; > + int ret; As Marc suggests, before looking at the FADT, you need something like: /* * Hyper-V VMs always have ACPI. */ if (acpi_disabled) return 0; ... where `acpi_disabled` is defined in <linux/acpi.h> (or via its includes), so you don't need to include any additional headers. > + > + /* > + * If we're in a VM on Hyper-V, the ACPI hypervisor_id field will > + * have the string "MsHyperV". > + */ > + if (strncmp((char *)&acpi_gbl_FADT.hypervisor_id, "MsHyperV", 8)) > + return -EINVAL; As Marc suggests, it's no an error for a platform to not have Hyper-V, so returning 0 in tihs case would be preferable. Otherwise this looks fine to me. Thanks, Mark. > + > + /* Setup the guest I[D */ > + guest_id = generate_guest_id(0, LINUX_VERSION_CODE, 0); > + hv_set_vpreg(HV_REGISTER_GUEST_OSID, guest_id); > + > + /* Get the features and hints from Hyper-V */ > + hv_get_vpreg_128(HV_REGISTER_FEATURES, &result); > + ms_hyperv.features = result.as32.a; > + ms_hyperv.priv_high = result.as32.b; > + ms_hyperv.misc_features = result.as32.c; > + > + hv_get_vpreg_128(HV_REGISTER_ENLIGHTENMENTS, &result); > + ms_hyperv.hints = result.as32.a; > + > + pr_info("Hyper-V: privilege flags low 0x%x, high 0x%x, hints 0x%x, misc 0x%x\n", > + ms_hyperv.features, ms_hyperv.priv_high, ms_hyperv.hints, > + ms_hyperv.misc_features); > + > + /* Get information about the Hyper-V host version */ > + hv_get_vpreg_128(HV_REGISTER_HYPERVISOR_VERSION, &result); > + a = result.as32.a; > + b = result.as32.b; > + c = result.as32.c; > + d = result.as32.d; > + pr_info("Hyper-V: Host Build %d.%d.%d.%d-%d-%d\n", > + b >> 16, b & 0xFFFF, a, d & 0xFFFFFF, c, d >> 24); > + > + ret = hv_common_init(); > + if (ret) > + return ret; > + > + ret = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "arm64/hyperv_init:online", > + hv_common_cpu_init, hv_common_cpu_die); > + if (ret < 0) { > + hv_common_free(); > + return ret; > + } > + > + hyperv_initialized = true; > + return 0; > +} > + > +early_initcall(hyperv_init); > + > +bool hv_is_hyperv_initialized(void) > +{ > + return hyperv_initialized; > +} > +EXPORT_SYMBOL_GPL(hv_is_hyperv_initialized); > -- > 1.8.3.1 >
From: Mark Rutland <mark.rutland@arm.com> Sent: Monday, August 2, 2021 9:26 AM > > On Tue, Jul 20, 2021 at 07:57:01AM -0700, Michael Kelley wrote: > > Add ARM64-specific code to initialize the Hyper-V > > hypervisor when booting as a guest VM. > > > > This code is built only when CONFIG_HYPERV is enabled. > > > > Signed-off-by: Michael Kelley <mikelley@microsoft.com> > > --- > > arch/arm64/hyperv/Makefile | 2 +- > > arch/arm64/hyperv/mshyperv.c | 83 ++++++++++++++++++++++++++++++++++++++++++++ > > 2 files changed, 84 insertions(+), 1 deletion(-) > > create mode 100644 arch/arm64/hyperv/mshyperv.c > > > > diff --git a/arch/arm64/hyperv/Makefile b/arch/arm64/hyperv/Makefile > > index 1697d30..87c31c0 100644 > > --- a/arch/arm64/hyperv/Makefile > > +++ b/arch/arm64/hyperv/Makefile > > @@ -1,2 +1,2 @@ > > # SPDX-License-Identifier: GPL-2.0 > > -obj-y := hv_core.o > > +obj-y := hv_core.o mshyperv.o > > diff --git a/arch/arm64/hyperv/mshyperv.c b/arch/arm64/hyperv/mshyperv.c > > new file mode 100644 > > index 0000000..2811fd0 > > --- /dev/null > > +++ b/arch/arm64/hyperv/mshyperv.c > > @@ -0,0 +1,83 @@ > > +// SPDX-License-Identifier: GPL-2.0 > > + > > +/* > > + * Core routines for interacting with Microsoft's Hyper-V hypervisor, > > + * including hypervisor initialization. > > + * > > + * Copyright (C) 2021, Microsoft, Inc. > > + * > > + * Author : Michael Kelley <mikelley@microsoft.com> > > + */ > > + > > +#include <linux/types.h> > > +#include <linux/acpi.h> > > +#include <linux/export.h> > > +#include <linux/errno.h> > > +#include <linux/version.h> > > +#include <linux/cpuhotplug.h> > > +#include <asm/mshyperv.h> > > + > > +static bool hyperv_initialized; > > + > > +static int __init hyperv_init(void) > > +{ > > + struct hv_get_vp_registers_output result; > > + u32 a, b, c, d; > > + u64 guest_id; > > + int ret; > > As Marc suggests, before looking at the FADT, you need something like: > > /* > * Hyper-V VMs always have ACPI. > */ > if (acpi_disabled) > return 0; > > ... where `acpi_disabled` is defined in <linux/acpi.h> (or via its > includes), so you don't need to include any additional headers. > > > + > > + /* > > + * If we're in a VM on Hyper-V, the ACPI hypervisor_id field will > > + * have the string "MsHyperV". > > + */ > > + if (strncmp((char *)&acpi_gbl_FADT.hypervisor_id, "MsHyperV", 8)) > > + return -EINVAL; > > As Marc suggests, it's no an error for a platform to not have Hyper-V, > so returning 0 in tihs case would be preferable. > > Otherwise this looks fine to me. > Thanks Marc and Mark. Good point that the code should cleanly handle the case where a kernel is built with CONFIG_HYPERV but running somewhere other than as a Hyper-V guest. Michael
diff --git a/arch/arm64/hyperv/Makefile b/arch/arm64/hyperv/Makefile index 1697d30..87c31c0 100644 --- a/arch/arm64/hyperv/Makefile +++ b/arch/arm64/hyperv/Makefile @@ -1,2 +1,2 @@ # SPDX-License-Identifier: GPL-2.0 -obj-y := hv_core.o +obj-y := hv_core.o mshyperv.o diff --git a/arch/arm64/hyperv/mshyperv.c b/arch/arm64/hyperv/mshyperv.c new file mode 100644 index 0000000..2811fd0 --- /dev/null +++ b/arch/arm64/hyperv/mshyperv.c @@ -0,0 +1,83 @@ +// SPDX-License-Identifier: GPL-2.0 + +/* + * Core routines for interacting with Microsoft's Hyper-V hypervisor, + * including hypervisor initialization. + * + * Copyright (C) 2021, Microsoft, Inc. + * + * Author : Michael Kelley <mikelley@microsoft.com> + */ + +#include <linux/types.h> +#include <linux/acpi.h> +#include <linux/export.h> +#include <linux/errno.h> +#include <linux/version.h> +#include <linux/cpuhotplug.h> +#include <asm/mshyperv.h> + +static bool hyperv_initialized; + +static int __init hyperv_init(void) +{ + struct hv_get_vp_registers_output result; + u32 a, b, c, d; + u64 guest_id; + int ret; + + /* + * If we're in a VM on Hyper-V, the ACPI hypervisor_id field will + * have the string "MsHyperV". + */ + if (strncmp((char *)&acpi_gbl_FADT.hypervisor_id, "MsHyperV", 8)) + return -EINVAL; + + /* Setup the guest ID */ + guest_id = generate_guest_id(0, LINUX_VERSION_CODE, 0); + hv_set_vpreg(HV_REGISTER_GUEST_OSID, guest_id); + + /* Get the features and hints from Hyper-V */ + hv_get_vpreg_128(HV_REGISTER_FEATURES, &result); + ms_hyperv.features = result.as32.a; + ms_hyperv.priv_high = result.as32.b; + ms_hyperv.misc_features = result.as32.c; + + hv_get_vpreg_128(HV_REGISTER_ENLIGHTENMENTS, &result); + ms_hyperv.hints = result.as32.a; + + pr_info("Hyper-V: privilege flags low 0x%x, high 0x%x, hints 0x%x, misc 0x%x\n", + ms_hyperv.features, ms_hyperv.priv_high, ms_hyperv.hints, + ms_hyperv.misc_features); + + /* Get information about the Hyper-V host version */ + hv_get_vpreg_128(HV_REGISTER_HYPERVISOR_VERSION, &result); + a = result.as32.a; + b = result.as32.b; + c = result.as32.c; + d = result.as32.d; + pr_info("Hyper-V: Host Build %d.%d.%d.%d-%d-%d\n", + b >> 16, b & 0xFFFF, a, d & 0xFFFFFF, c, d >> 24); + + ret = hv_common_init(); + if (ret) + return ret; + + ret = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "arm64/hyperv_init:online", + hv_common_cpu_init, hv_common_cpu_die); + if (ret < 0) { + hv_common_free(); + return ret; + } + + hyperv_initialized = true; + return 0; +} + +early_initcall(hyperv_init); + +bool hv_is_hyperv_initialized(void) +{ + return hyperv_initialized; +} +EXPORT_SYMBOL_GPL(hv_is_hyperv_initialized);
Add ARM64-specific code to initialize the Hyper-V hypervisor when booting as a guest VM. This code is built only when CONFIG_HYPERV is enabled. Signed-off-by: Michael Kelley <mikelley@microsoft.com> --- arch/arm64/hyperv/Makefile | 2 +- arch/arm64/hyperv/mshyperv.c | 83 ++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 84 insertions(+), 1 deletion(-) create mode 100644 arch/arm64/hyperv/mshyperv.c