[PATCH 0/2] Add support for clean shutdown with MSHV

[PATCH 0/2] Add support for clean shutdown with MSHV

[Praveen K Paladugu]

Add support for clean shutdown of the root partition when running on MSHV
hypervisor.

Praveen K Paladugu (2):
  hyperv: Add definitions for MSHV sleep state configuration
  hyperv: Enable clean shutdown for root partition with MSHV

 arch/x86/hyperv/hv_init.c      |   7 ++
 drivers/hv/hv_common.c         | 118 +++++++++++++++++++++++++++++++++
 include/asm-generic/mshyperv.h |   1 +
 include/hyperv/hvgdk_mini.h    |   4 +-
 include/hyperv/hvhdk_mini.h    |  33 +++++++++
 5 files changed, 162 insertions(+), 1 deletion(-)

-- 
2.51.0

[PATCH 1/2] hyperv: Add definitions for MSHV sleep state configuration

[Praveen K Paladugu]

Add the definitions required to configure sleep states in mshv hypervsior.

Signed-off-by: Praveen K Paladugu <prapal@linux.microsoft.com>
Co-developed-by: Anatol Belski <anbelski@linux.microsoft.com>
Signed-off-by: Anatol Belski <anbelski@linux.microsoft.com>
---
 include/hyperv/hvgdk_mini.h |  4 +++-
 include/hyperv/hvhdk_mini.h | 33 +++++++++++++++++++++++++++++++++
 2 files changed, 36 insertions(+), 1 deletion(-)

diff --git a/include/hyperv/hvgdk_mini.h b/include/hyperv/hvgdk_mini.h
index 77abddfc750e..943df5d292f2 100644
--- a/include/hyperv/hvgdk_mini.h
+++ b/include/hyperv/hvgdk_mini.h
@@ -464,18 +464,20 @@ union hv_vp_assist_msr_contents {	 /* HV_REGISTER_VP_ASSIST_PAGE */
 #define HVCALL_RESET_DEBUG_SESSION			0x006b
 #define HVCALL_MAP_STATS_PAGE				0x006c
 #define HVCALL_UNMAP_STATS_PAGE				0x006d
+#define HVCALL_SET_SYSTEM_PROPERTY			0x006f
 #define HVCALL_ADD_LOGICAL_PROCESSOR			0x0076
 #define HVCALL_GET_SYSTEM_PROPERTY			0x007b
 #define HVCALL_MAP_DEVICE_INTERRUPT			0x007c
 #define HVCALL_UNMAP_DEVICE_INTERRUPT			0x007d
 #define HVCALL_RETARGET_INTERRUPT			0x007e
+#define HVCALL_ENTER_SLEEP_STATE			0x0084
 #define HVCALL_NOTIFY_PORT_RING_EMPTY			0x008b
 #define HVCALL_REGISTER_INTERCEPT_RESULT		0x0091
 #define HVCALL_ASSERT_VIRTUAL_INTERRUPT			0x0094
 #define HVCALL_CREATE_PORT				0x0095
 #define HVCALL_CONNECT_PORT				0x0096
 #define HVCALL_START_VP					0x0099
-#define HVCALL_GET_VP_INDEX_FROM_APIC_ID			0x009a
+#define HVCALL_GET_VP_INDEX_FROM_APIC_ID		0x009a
 #define HVCALL_FLUSH_GUEST_PHYSICAL_ADDRESS_SPACE	0x00af
 #define HVCALL_FLUSH_GUEST_PHYSICAL_ADDRESS_LIST	0x00b0
 #define HVCALL_SIGNAL_EVENT_DIRECT			0x00c0
diff --git a/include/hyperv/hvhdk_mini.h b/include/hyperv/hvhdk_mini.h
index 858f6a3925b3..8fa86c014c25 100644
--- a/include/hyperv/hvhdk_mini.h
+++ b/include/hyperv/hvhdk_mini.h
@@ -114,10 +114,24 @@ enum hv_snp_status {
 
 enum hv_system_property {
 	/* Add more values when needed */
+	HV_SYSTEM_PROPERTY_SLEEP_STATE = 3,
 	HV_SYSTEM_PROPERTY_SCHEDULER_TYPE = 15,
 	HV_DYNAMIC_PROCESSOR_FEATURE_PROPERTY = 21,
 };
 
+enum hv_sleep_state {
+	HV_SLEEP_STATE_S1 = 1,
+	HV_SLEEP_STATE_S2 = 2,
+	HV_SLEEP_STATE_S3 = 3,
+	HV_SLEEP_STATE_S4 = 4,
+	HV_SLEEP_STATE_S5 = 5,
+	/*
+	 * After hypervisor has received this, any follow up sleep
+	 * state registration requests will be rejected.
+	 */
+	HV_SLEEP_STATE_LOCK = 6
+};
+
 enum hv_dynamic_processor_feature_property {
 	/* Add more values when needed */
 	HV_X64_DYNAMIC_PROCESSOR_FEATURE_MAX_ENCRYPTED_PARTITIONS = 13,
@@ -145,6 +159,25 @@ struct hv_output_get_system_property {
 	};
 } __packed;
 
+struct hv_sleep_state_info {
+	u32 sleep_state; /* enum hv_sleep_state */
+	u8 pm1a_slp_typ;
+	u8 pm1b_slp_typ;
+} __packed;
+
+struct hv_input_set_system_property {
+	u32 property_id; /* enum hv_system_property */
+	u32 reserved;
+	union {
+		/* More fields to be filled in when needed */
+		struct hv_sleep_state_info set_sleep_state_info;
+	};
+} __packed;
+
+struct hv_input_enter_sleep_state {     /* HV_INPUT_ENTER_SLEEP_STATE */
+	u32 sleep_state;        /* enum hv_sleep_state */
+} __packed;
+
 struct hv_input_map_stats_page {
 	u32 type; /* enum hv_stats_object_type */
 	u32 padding;
-- 
2.51.0

[PATCH 2/2] hyperv: Enable clean shutdown for root partition with MSHV

[Praveen K Paladugu]

This commit enables the root partition to perform a clean shutdown when
running with MSHV hypervisor.

Signed-off-by: Praveen K Paladugu <prapal@linux.microsoft.com>
Co-developed-by: Anatol Belski <anbelski@linux.microsoft.com>
Signed-off-by: Anatol Belski <anbelski@linux.microsoft.com>
---
 arch/x86/hyperv/hv_init.c      |   7 ++
 drivers/hv/hv_common.c         | 118 +++++++++++++++++++++++++++++++++
 include/asm-generic/mshyperv.h |   1 +
 3 files changed, 126 insertions(+)

diff --git a/arch/x86/hyperv/hv_init.c b/arch/x86/hyperv/hv_init.c
index afdbda2dd7b7..57bd96671ead 100644
--- a/arch/x86/hyperv/hv_init.c
+++ b/arch/x86/hyperv/hv_init.c
@@ -510,6 +510,13 @@ void __init hyperv_init(void)
 		memunmap(src);
 
 		hv_remap_tsc_clocksource();
+		/*
+		 * The notifier registration might fail at various hops.
+		 * Corresponding error messages will land in dmesg. There is
+		 * otherwise nothing that can be specifically done to handle
+		 * failures here.
+		 */
+		(void)hv_sleep_notifiers_register();
 	} else {
 		hypercall_msr.guest_physical_address = vmalloc_to_pfn(hv_hypercall_pg);
 		wrmsrq(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64);
diff --git a/drivers/hv/hv_common.c b/drivers/hv/hv_common.c
index e109a620c83f..c5165deb5278 100644
--- a/drivers/hv/hv_common.c
+++ b/drivers/hv/hv_common.c
@@ -837,3 +837,121 @@ const char *hv_result_to_string(u64 status)
 	return "Unknown";
 }
 EXPORT_SYMBOL_GPL(hv_result_to_string);
+
+/*
+ * Corresponding sleep states have to be initialized, in order for a subsequent
+ * HVCALL_ENTER_SLEEP_STATE call to succeed. Currently only S5 state as per
+ * ACPI 6.4 chapter 7.4.2 is relevant, while S1, S2 and S3 can be supported.
+ *
+ * ACPI should be initialized and should support S5 sleep state when this method
+ * is called, so that, it can extract correct PM values and pass them to hv.
+ */
+static int hv_initialize_sleep_states(void)
+{
+	u64 status;
+	unsigned long flags;
+	struct hv_input_set_system_property *in;
+	acpi_status acpi_status;
+	u8 sleep_type_a, sleep_type_b;
+
+	if (!acpi_sleep_state_supported(ACPI_STATE_S5)) {
+		pr_err("%s: S5 sleep state not supported.\n", __func__);
+		return -ENODEV;
+	}
+
+	acpi_status = acpi_get_sleep_type_data(ACPI_STATE_S5,
+						&sleep_type_a, &sleep_type_b);
+	if (ACPI_FAILURE(acpi_status))
+		return -ENODEV;
+
+	local_irq_save(flags);
+	in = (struct hv_input_set_system_property *)(*this_cpu_ptr(
+		hyperv_pcpu_input_arg));
+
+	in->property_id = HV_SYSTEM_PROPERTY_SLEEP_STATE;
+	in->set_sleep_state_info.sleep_state = HV_SLEEP_STATE_S5;
+	in->set_sleep_state_info.pm1a_slp_typ = sleep_type_a;
+	in->set_sleep_state_info.pm1b_slp_typ = sleep_type_b;
+
+	status = hv_do_hypercall(HVCALL_SET_SYSTEM_PROPERTY, in, NULL);
+	local_irq_restore(flags);
+
+	if (!hv_result_success(status)) {
+		pr_err("%s: %s\n", __func__, hv_result_to_string(status));
+		return hv_result_to_errno(status);
+	}
+
+	return 0;
+}
+
+static int hv_call_enter_sleep_state(u32 sleep_state)
+{
+	u64 status;
+	int ret;
+	unsigned long flags;
+	struct hv_input_enter_sleep_state *in;
+
+	ret = hv_initialize_sleep_states();
+	if (ret)
+		return ret;
+
+	local_irq_save(flags);
+	in = (struct hv_input_enter_sleep_state *)
+			(*this_cpu_ptr(hyperv_pcpu_input_arg));
+	in->sleep_state = (enum hv_sleep_state)sleep_state;
+
+	status = hv_do_hypercall(HVCALL_ENTER_SLEEP_STATE, in, NULL);
+	local_irq_restore(flags);
+
+	if (!hv_result_success(status)) {
+		pr_err("%s: %s\n", __func__, hv_result_to_string(status));
+		return hv_result_to_errno(status);
+	}
+
+	return 0;
+}
+
+static int hv_reboot_notifier_handler(struct notifier_block *this,
+				      unsigned long code, void *another)
+{
+	int ret = 0;
+
+	if (SYS_HALT == code || SYS_POWER_OFF == code)
+		ret = hv_call_enter_sleep_state(HV_SLEEP_STATE_S5);
+
+	return ret ? NOTIFY_DONE : NOTIFY_OK;
+}
+
+static struct notifier_block hv_reboot_notifier = {
+	.notifier_call  = hv_reboot_notifier_handler,
+};
+
+static int hv_acpi_sleep_handler(u8 sleep_state, u32 pm1a_cnt, u32 pm1b_cnt)
+{
+	int ret = 0;
+
+	if (sleep_state == ACPI_STATE_S5)
+		ret = hv_call_enter_sleep_state(HV_SLEEP_STATE_S5);
+
+	return ret == 0 ? 1 : -1;
+}
+
+static int hv_acpi_extended_sleep_handler(u8 sleep_state, u32 val_a, u32 val_b)
+{
+	return hv_acpi_sleep_handler(sleep_state, val_a, val_b);
+}
+
+int hv_sleep_notifiers_register(void)
+{
+	int ret;
+
+	acpi_os_set_prepare_sleep(&hv_acpi_sleep_handler);
+	acpi_os_set_prepare_extended_sleep(&hv_acpi_extended_sleep_handler);
+
+	ret = register_reboot_notifier(&hv_reboot_notifier);
+	if (ret)
+		pr_err("%s: cannot register reboot notifier %d\n",
+			__func__, ret);
+
+	return ret;
+}
diff --git a/include/asm-generic/mshyperv.h b/include/asm-generic/mshyperv.h
index 64ba6bc807d9..903d089aba82 100644
--- a/include/asm-generic/mshyperv.h
+++ b/include/asm-generic/mshyperv.h
@@ -339,6 +339,7 @@ u64 hv_tdx_hypercall(u64 control, u64 param1, u64 param2);
 void hyperv_cleanup(void);
 bool hv_query_ext_cap(u64 cap_query);
 void hv_setup_dma_ops(struct device *dev, bool coherent);
+int hv_sleep_notifiers_register(void);
 #else /* CONFIG_HYPERV */
 static inline void hv_identify_partition_type(void) {}
 static inline bool hv_is_hyperv_initialized(void) { return false; }
-- 
2.51.0

Re: [PATCH 2/2] hyperv: Enable clean shutdown for root partition with MSHV

[Easwar Hariharan]

On 10/9/2025 8:58 AM, Praveen K Paladugu wrote:
> This commit enables the root partition to perform a clean shutdown when
> running with MSHV hypervisor.

No "This commit..." please

> 
> Signed-off-by: Praveen K Paladugu <prapal@linux.microsoft.com>
> Co-developed-by: Anatol Belski <anbelski@linux.microsoft.com>
> Signed-off-by: Anatol Belski <anbelski@linux.microsoft.com>
> ---
>  arch/x86/hyperv/hv_init.c      |   7 ++
>  drivers/hv/hv_common.c         | 118 +++++++++++++++++++++++++++++++++
>  include/asm-generic/mshyperv.h |   1 +
>  3 files changed, 126 insertions(+)
> 
> diff --git a/arch/x86/hyperv/hv_init.c b/arch/x86/hyperv/hv_init.c
> index afdbda2dd7b7..57bd96671ead 100644
> --- a/arch/x86/hyperv/hv_init.c
> +++ b/arch/x86/hyperv/hv_init.c
> @@ -510,6 +510,13 @@ void __init hyperv_init(void)
>  		memunmap(src);
>  
>  		hv_remap_tsc_clocksource();
> +		/*
> +		 * The notifier registration might fail at various hops.
> +		 * Corresponding error messages will land in dmesg. There is
> +		 * otherwise nothing that can be specifically done to handle
> +		 * failures here.
> +		 */
> +		(void)hv_sleep_notifiers_register();
>  	} else {
>  		hypercall_msr.guest_physical_address = vmalloc_to_pfn(hv_hypercall_pg);
>  		wrmsrq(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64);
> diff --git a/drivers/hv/hv_common.c b/drivers/hv/hv_common.c
> index e109a620c83f..c5165deb5278 100644
> --- a/drivers/hv/hv_common.c
> +++ b/drivers/hv/hv_common.c
> @@ -837,3 +837,121 @@ const char *hv_result_to_string(u64 status)
>  	return "Unknown";
>  }
>  EXPORT_SYMBOL_GPL(hv_result_to_string);
> +
> +/*
> + * Corresponding sleep states have to be initialized, in order for a subsequent
> + * HVCALL_ENTER_SLEEP_STATE call to succeed. Currently only S5 state as per
> + * ACPI 6.4 chapter 7.4.2 is relevant, while S1, S2 and S3 can be supported.
> + *
> + * ACPI should be initialized and should support S5 sleep state when this method
> + * is called, so that, it can extract correct PM values and pass them to hv.

Nit: No need for this   ^ comma, i.e. "...when this method is called, so that it can..."

> + */
> +static int hv_initialize_sleep_states(void)
> +{
> +	u64 status;
> +	unsigned long flags;
> +	struct hv_input_set_system_property *in;
> +	acpi_status acpi_status;
> +	u8 sleep_type_a, sleep_type_b;
> +
> +	if (!acpi_sleep_state_supported(ACPI_STATE_S5)) {
> +		pr_err("%s: S5 sleep state not supported.\n", __func__);
> +		return -ENODEV;
> +	}
> +
> +	acpi_status = acpi_get_sleep_type_data(ACPI_STATE_S5,
> +						&sleep_type_a, &sleep_type_b);
> +	if (ACPI_FAILURE(acpi_status))
> +		return -ENODEV;
> +
> +	local_irq_save(flags);
> +	in = (struct hv_input_set_system_property *)(*this_cpu_ptr(
> +		hyperv_pcpu_input_arg));

Other users don't have these casts, why is it necessary here?

> +
> +	in->property_id = HV_SYSTEM_PROPERTY_SLEEP_STATE;
> +	in->set_sleep_state_info.sleep_state = HV_SLEEP_STATE_S5;
> +	in->set_sleep_state_info.pm1a_slp_typ = sleep_type_a;
> +	in->set_sleep_state_info.pm1b_slp_typ = sleep_type_b;
> +
> +	status = hv_do_hypercall(HVCALL_SET_SYSTEM_PROPERTY, in, NULL);
> +	local_irq_restore(flags);
> +
> +	if (!hv_result_success(status)) {
> +		pr_err("%s: %s\n", __func__, hv_result_to_string(status));
> +		return hv_result_to_errno(status);
> +	}
> +
> +	return 0;
> +}
> +
> +static int hv_call_enter_sleep_state(u32 sleep_state)
> +{
> +	u64 status;
> +	int ret;
> +	unsigned long flags;
> +	struct hv_input_enter_sleep_state *in;
> +
> +	ret = hv_initialize_sleep_states();
> +	if (ret)
> +		return ret;
> +
> +	local_irq_save(flags);
> +	in = (struct hv_input_enter_sleep_state *)
> +			(*this_cpu_ptr(hyperv_pcpu_input_arg));
> +	in->sleep_state = (enum hv_sleep_state)sleep_state;
> +

More casts...

> +	status = hv_do_hypercall(HVCALL_ENTER_SLEEP_STATE, in, NULL);
> +	local_irq_restore(flags);
> +
> +	if (!hv_result_success(status)) {
> +		pr_err("%s: %s\n", __func__, hv_result_to_string(status));
> +		return hv_result_to_errno(status);
> +	}
> +
> +	return 0;
> +}
> +
> +static int hv_reboot_notifier_handler(struct notifier_block *this,
> +				      unsigned long code, void *another)
> +{
> +	int ret = 0;
> +
> +	if (SYS_HALT == code || SYS_POWER_OFF == code)

Usually the variable is on the left of the comparison with the constant

> +		ret = hv_call_enter_sleep_state(HV_SLEEP_STATE_S5);
> +
> +	return ret ? NOTIFY_DONE : NOTIFY_OK;
> +}
> +
> +static struct notifier_block hv_reboot_notifier = {
> +	.notifier_call  = hv_reboot_notifier_handler,
> +};
> +
> +static int hv_acpi_sleep_handler(u8 sleep_state, u32 pm1a_cnt, u32 pm1b_cnt)
> +{
> +	int ret = 0;
> +
> +	if (sleep_state == ACPI_STATE_S5)
> +		ret = hv_call_enter_sleep_state(HV_SLEEP_STATE_S5);
> +
> +	return ret == 0 ? 1 : -1;
> +}
> +
> +static int hv_acpi_extended_sleep_handler(u8 sleep_state, u32 val_a, u32 val_b)
> +{
> +	return hv_acpi_sleep_handler(sleep_state, val_a, val_b);
> +}
> +
> +int hv_sleep_notifiers_register(void)
> +{
> +	int ret;
> +
> +	acpi_os_set_prepare_sleep(&hv_acpi_sleep_handler);
> +	acpi_os_set_prepare_extended_sleep(&hv_acpi_extended_sleep_handler);
> +
> +	ret = register_reboot_notifier(&hv_reboot_notifier);
> +	if (ret)
> +		pr_err("%s: cannot register reboot notifier %d\n",
> +			__func__, ret);
> +
> +	return ret;
> +}
> diff --git a/include/asm-generic/mshyperv.h b/include/asm-generic/mshyperv.h
> index 64ba6bc807d9..903d089aba82 100644
> --- a/include/asm-generic/mshyperv.h
> +++ b/include/asm-generic/mshyperv.h
> @@ -339,6 +339,7 @@ u64 hv_tdx_hypercall(u64 control, u64 param1, u64 param2);
>  void hyperv_cleanup(void);
>  bool hv_query_ext_cap(u64 cap_query);
>  void hv_setup_dma_ops(struct device *dev, bool coherent);
> +int hv_sleep_notifiers_register(void);

Does this still work when CONFIG_HYPERV = n, i.e. do we need a stub below? Also, this looks
like it's only implemented for x86, so perhaps this declaration should be in arch/x86/include/asm/mshyperv.h
instead of asm-generic?

>  #else /* CONFIG_HYPERV */
>  static inline void hv_identify_partition_type(void) {}
>  static inline bool hv_is_hyperv_initialized(void) { return false; }

Re: [PATCH 1/2] hyperv: Add definitions for MSHV sleep state configuration

[Easwar Hariharan]

On 10/9/2025 8:58 AM, Praveen K Paladugu wrote:
> Add the definitions required to configure sleep states in mshv hypervsior.
> 
> Signed-off-by: Praveen K Paladugu <prapal@linux.microsoft.com>
> Co-developed-by: Anatol Belski <anbelski@linux.microsoft.com>
> Signed-off-by: Anatol Belski <anbelski@linux.microsoft.com>
> ---
>  include/hyperv/hvgdk_mini.h |  4 +++-
>  include/hyperv/hvhdk_mini.h | 33 +++++++++++++++++++++++++++++++++
>  2 files changed, 36 insertions(+), 1 deletion(-)

Reviewed-by: Easwar Hariharan <easwar.hariharan@linux.microsoft.com>

Re: [PATCH 2/2] hyperv: Enable clean shutdown for root partition with MSHV

[Nuno Das Neves]

On 10/9/2025 8:58 AM, Praveen K Paladugu wrote:
> This commit enables the root partition to perform a clean shutdown when
> running with MSHV hypervisor.
> 

Commit message could briefly explain what the current problem is - what is
wrong with the current shutdown and how does this fix it?

> Signed-off-by: Praveen K Paladugu <prapal@linux.microsoft.com>
> Co-developed-by: Anatol Belski <anbelski@linux.microsoft.com>
> Signed-off-by: Anatol Belski <anbelski@linux.microsoft.com>
> ---
>  arch/x86/hyperv/hv_init.c      |   7 ++
>  drivers/hv/hv_common.c         | 118 +++++++++++++++++++++++++++++++++
>  include/asm-generic/mshyperv.h |   1 +
>  3 files changed, 126 insertions(+)
> 
> diff --git a/arch/x86/hyperv/hv_init.c b/arch/x86/hyperv/hv_init.c
> index afdbda2dd7b7..57bd96671ead 100644
> --- a/arch/x86/hyperv/hv_init.c
> +++ b/arch/x86/hyperv/hv_init.c
> @@ -510,6 +510,13 @@ void __init hyperv_init(void)
>  		memunmap(src);
>  
>  		hv_remap_tsc_clocksource();
> +		/*
> +		 * The notifier registration might fail at various hops.
> +		 * Corresponding error messages will land in dmesg. There is
> +		 * otherwise nothing that can be specifically done to handle
> +		 * failures here.
> +		 */
> +		(void)hv_sleep_notifiers_register();
>  	} else {
>  		hypercall_msr.guest_physical_address = vmalloc_to_pfn(hv_hypercall_pg);
>  		wrmsrq(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64);
> diff --git a/drivers/hv/hv_common.c b/drivers/hv/hv_common.c
> index e109a620c83f..c5165deb5278 100644
> --- a/drivers/hv/hv_common.c
> +++ b/drivers/hv/hv_common.c
> @@ -837,3 +837,121 @@ const char *hv_result_to_string(u64 status)
>  	return "Unknown";
>  }
>  EXPORT_SYMBOL_GPL(hv_result_to_string);
> +
> +/*
> + * Corresponding sleep states have to be initialized, in order for a subsequent

The comma in the above line is not needed.

> + * HVCALL_ENTER_SLEEP_STATE call to succeed. Currently only S5 state as per
> + * ACPI 6.4 chapter 7.4.2 is relevant, while S1, S2 and S3 can be supported.
> + *
> + * ACPI should be initialized and should support S5 sleep state when this method
> + * is called, so that, it can extract correct PM values and pass them to hv.
> + */
> +static int hv_initialize_sleep_states(void)
> +{
> +	u64 status;
> +	unsigned long flags;
> +	struct hv_input_set_system_property *in;
> +	acpi_status acpi_status;
> +	u8 sleep_type_a, sleep_type_b;
> +
> +	if (!acpi_sleep_state_supported(ACPI_STATE_S5)) {
> +		pr_err("%s: S5 sleep state not supported.\n", __func__);
> +		return -ENODEV;
> +	}
> +
> +	acpi_status = acpi_get_sleep_type_data(ACPI_STATE_S5,
> +						&sleep_type_a, &sleep_type_b);
> +	if (ACPI_FAILURE(acpi_status))
> +		return -ENODEV;
> +
> +	local_irq_save(flags);
> +	in = (struct hv_input_set_system_property *)(*this_cpu_ptr(
> +		hyperv_pcpu_input_arg));
> +

The input struct contains a reserved field that should be zero.
You could either set it to zero explicitly or preferably just zero the whole
struct here. Doing that gives confidence to a reader that no field is left
uninitialized even if they're not familiar with the struct.

> +	in->property_id = HV_SYSTEM_PROPERTY_SLEEP_STATE;
> +	in->set_sleep_state_info.sleep_state = HV_SLEEP_STATE_S5;
> +	in->set_sleep_state_info.pm1a_slp_typ = sleep_type_a;
> +	in->set_sleep_state_info.pm1b_slp_typ = sleep_type_b;
> +
> +	status = hv_do_hypercall(HVCALL_SET_SYSTEM_PROPERTY, in, NULL);
> +	local_irq_restore(flags);
> +
> +	if (!hv_result_success(status)) {
> +		pr_err("%s: %s\n", __func__, hv_result_to_string(status));

Use hv_status_err(status, "\n");

> +		return hv_result_to_errno(status);
> +	}
> +
> +	return 0;
> +}
> +
> +static int hv_call_enter_sleep_state(u32 sleep_state)
> +{
> +	u64 status;
> +	int ret;
> +	unsigned long flags;
> +	struct hv_input_enter_sleep_state *in;
> +
> +	ret = hv_initialize_sleep_states();
> +	if (ret)
> +		return ret;
> +
> +	local_irq_save(flags);
> +	in = (struct hv_input_enter_sleep_state *)
> +			(*this_cpu_ptr(hyperv_pcpu_input_arg));
> +	in->sleep_state = (enum hv_sleep_state)sleep_state;
> +
> +	status = hv_do_hypercall(HVCALL_ENTER_SLEEP_STATE, in, NULL);
> +	local_irq_restore(flags);
> +
> +	if (!hv_result_success(status)) {
> +		pr_err("%s: %s\n", __func__, hv_result_to_string(status));

Use hv_status_err(status, "\n");

> +		return hv_result_to_errno(status);
> +	}
> +
> +	return 0;
> +}
> +
> +static int hv_reboot_notifier_handler(struct notifier_block *this,
> +				      unsigned long code, void *another)
> +{
> +	int ret = 0;
> +
> +	if (SYS_HALT == code || SYS_POWER_OFF == code)
> +		ret = hv_call_enter_sleep_state(HV_SLEEP_STATE_S5);
> +
> +	return ret ? NOTIFY_DONE : NOTIFY_OK;
> +}
> +
> +static struct notifier_block hv_reboot_notifier = {
> +	.notifier_call  = hv_reboot_notifier_handler,
> +};
> +
> +static int hv_acpi_sleep_handler(u8 sleep_state, u32 pm1a_cnt, u32 pm1b_cnt)
> +{
> +	int ret = 0;
> +
> +	if (sleep_state == ACPI_STATE_S5)
> +		ret = hv_call_enter_sleep_state(HV_SLEEP_STATE_S5);
> +
> +	return ret == 0 ? 1 : -1;
> +}
> +
> +static int hv_acpi_extended_sleep_handler(u8 sleep_state, u32 val_a, u32 val_b)
> +{
> +	return hv_acpi_sleep_handler(sleep_state, val_a, val_b);
> +}
> +
> +int hv_sleep_notifiers_register(void)
> +{
> +	int ret;
> +
> +	acpi_os_set_prepare_sleep(&hv_acpi_sleep_handler);
> +	acpi_os_set_prepare_extended_sleep(&hv_acpi_extended_sleep_handler);
> +
> +	ret = register_reboot_notifier(&hv_reboot_notifier);
> +	if (ret)
> +		pr_err("%s: cannot register reboot notifier %d\n",
> +			__func__, ret);
> +
> +	return ret;
> +}
> diff --git a/include/asm-generic/mshyperv.h b/include/asm-generic/mshyperv.h
> index 64ba6bc807d9..903d089aba82 100644
> --- a/include/asm-generic/mshyperv.h
> +++ b/include/asm-generic/mshyperv.h
> @@ -339,6 +339,7 @@ u64 hv_tdx_hypercall(u64 control, u64 param1, u64 param2);
>  void hyperv_cleanup(void);
>  bool hv_query_ext_cap(u64 cap_query);
>  void hv_setup_dma_ops(struct device *dev, bool coherent);
> +int hv_sleep_notifiers_register(void);
>  #else /* CONFIG_HYPERV */
>  static inline void hv_identify_partition_type(void) {}
>  static inline bool hv_is_hyperv_initialized(void) { return false; }

Re: [PATCH 1/2] hyperv: Add definitions for MSHV sleep state configuration

[Nuno Das Neves]

On 10/9/2025 8:58 AM, Praveen K Paladugu wrote:
> Add the definitions required to configure sleep states in mshv hypervsior.
> 
> Signed-off-by: Praveen K Paladugu <prapal@linux.microsoft.com>
> Co-developed-by: Anatol Belski <anbelski@linux.microsoft.com>
> Signed-off-by: Anatol Belski <anbelski@linux.microsoft.com>
> ---
>  include/hyperv/hvgdk_mini.h |  4 +++-
>  include/hyperv/hvhdk_mini.h | 33 +++++++++++++++++++++++++++++++++
>  2 files changed, 36 insertions(+), 1 deletion(-)
> 
> diff --git a/include/hyperv/hvgdk_mini.h b/include/hyperv/hvgdk_mini.h
> index 77abddfc750e..943df5d292f2 100644
> --- a/include/hyperv/hvgdk_mini.h
> +++ b/include/hyperv/hvgdk_mini.h
> @@ -464,18 +464,20 @@ union hv_vp_assist_msr_contents {	 /* HV_REGISTER_VP_ASSIST_PAGE */
>  #define HVCALL_RESET_DEBUG_SESSION			0x006b
>  #define HVCALL_MAP_STATS_PAGE				0x006c
>  #define HVCALL_UNMAP_STATS_PAGE				0x006d
> +#define HVCALL_SET_SYSTEM_PROPERTY			0x006f
>  #define HVCALL_ADD_LOGICAL_PROCESSOR			0x0076
>  #define HVCALL_GET_SYSTEM_PROPERTY			0x007b
>  #define HVCALL_MAP_DEVICE_INTERRUPT			0x007c
>  #define HVCALL_UNMAP_DEVICE_INTERRUPT			0x007d
>  #define HVCALL_RETARGET_INTERRUPT			0x007e
> +#define HVCALL_ENTER_SLEEP_STATE			0x0084
>  #define HVCALL_NOTIFY_PORT_RING_EMPTY			0x008b
>  #define HVCALL_REGISTER_INTERCEPT_RESULT		0x0091
>  #define HVCALL_ASSERT_VIRTUAL_INTERRUPT			0x0094
>  #define HVCALL_CREATE_PORT				0x0095
>  #define HVCALL_CONNECT_PORT				0x0096
>  #define HVCALL_START_VP					0x0099
> -#define HVCALL_GET_VP_INDEX_FROM_APIC_ID			0x009a
> +#define HVCALL_GET_VP_INDEX_FROM_APIC_ID		0x009a
>  #define HVCALL_FLUSH_GUEST_PHYSICAL_ADDRESS_SPACE	0x00af
>  #define HVCALL_FLUSH_GUEST_PHYSICAL_ADDRESS_LIST	0x00b0
>  #define HVCALL_SIGNAL_EVENT_DIRECT			0x00c0
> diff --git a/include/hyperv/hvhdk_mini.h b/include/hyperv/hvhdk_mini.h
> index 858f6a3925b3..8fa86c014c25 100644
> --- a/include/hyperv/hvhdk_mini.h
> +++ b/include/hyperv/hvhdk_mini.h
> @@ -114,10 +114,24 @@ enum hv_snp_status {
>  
>  enum hv_system_property {
>  	/* Add more values when needed */
> +	HV_SYSTEM_PROPERTY_SLEEP_STATE = 3,
>  	HV_SYSTEM_PROPERTY_SCHEDULER_TYPE = 15,
>  	HV_DYNAMIC_PROCESSOR_FEATURE_PROPERTY = 21,
>  };
>  
> +enum hv_sleep_state {
> +	HV_SLEEP_STATE_S1 = 1,
> +	HV_SLEEP_STATE_S2 = 2,
> +	HV_SLEEP_STATE_S3 = 3,
> +	HV_SLEEP_STATE_S4 = 4,
> +	HV_SLEEP_STATE_S5 = 5,
> +	/*
> +	 * After hypervisor has received this, any follow up sleep
> +	 * state registration requests will be rejected.
> +	 */
> +	HV_SLEEP_STATE_LOCK = 6
> +};
> +
>  enum hv_dynamic_processor_feature_property {
>  	/* Add more values when needed */
>  	HV_X64_DYNAMIC_PROCESSOR_FEATURE_MAX_ENCRYPTED_PARTITIONS = 13,
> @@ -145,6 +159,25 @@ struct hv_output_get_system_property {
>  	};
>  } __packed;
>  
> +struct hv_sleep_state_info {
> +	u32 sleep_state; /* enum hv_sleep_state */
> +	u8 pm1a_slp_typ;
> +	u8 pm1b_slp_typ;
> +} __packed;
> +
> +struct hv_input_set_system_property {
> +	u32 property_id; /* enum hv_system_property */
> +	u32 reserved;
> +	union {
> +		/* More fields to be filled in when needed */
> +		struct hv_sleep_state_info set_sleep_state_info;
> +	};
> +} __packed;
> +
> +struct hv_input_enter_sleep_state {     /* HV_INPUT_ENTER_SLEEP_STATE */
> +	u32 sleep_state;        /* enum hv_sleep_state */
> +} __packed;
> +
>  struct hv_input_map_stats_page {
>  	u32 type; /* enum hv_stats_object_type */
>  	u32 padding;

Reviewed-by: Nuno Das Neves <nunodasneves@linux.microsoft.com>

Re: [PATCH 0/2] Add support for clean shutdown with MSHV

[Stanislav Kinsburskii]

On Thu, Oct 09, 2025 at 10:58:49AM -0500, Praveen K Paladugu wrote:
> Add support for clean shutdown of the root partition when running on MSHV
> hypervisor.
> 
> Praveen K Paladugu (2):
>   hyperv: Add definitions for MSHV sleep state configuration
>   hyperv: Enable clean shutdown for root partition with MSHV
> 

There is no need to split this logic to two patches: the first one
doesn't make sense without the second one, so it would be better to
squash them.

Thanks,
Stanislav

>  arch/x86/hyperv/hv_init.c      |   7 ++
>  drivers/hv/hv_common.c         | 118 +++++++++++++++++++++++++++++++++
>  include/asm-generic/mshyperv.h |   1 +
>  include/hyperv/hvgdk_mini.h    |   4 +-
>  include/hyperv/hvhdk_mini.h    |  33 +++++++++
>  5 files changed, 162 insertions(+), 1 deletion(-)
> 
> -- 
> 2.51.0
> 

Re: [PATCH 2/2] hyperv: Enable clean shutdown for root partition with MSHV

[kernel test robot]

Hi Praveen,

kernel test robot noticed the following build errors:

[auto build test ERROR on tip/x86/core]
[also build test ERROR on arnd-asm-generic/master soc/for-next linus/master v6.17 next-20251010]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Praveen-K-Paladugu/hyperv-Add-definitions-for-MSHV-sleep-state-configuration/20251010-122914
base:   tip/x86/core
patch link:    https://lore.kernel.org/r/20251009160501.6356-3-prapal%40linux.microsoft.com
patch subject: [PATCH 2/2] hyperv: Enable clean shutdown for root partition with MSHV
config: arm64-randconfig-002-20251011 (https://download.01.org/0day-ci/archive/20251011/202510111908.EESLF0ZB-lkp@intel.com/config)
compiler: aarch64-linux-gcc (GCC) 12.5.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20251011/202510111908.EESLF0ZB-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202510111908.EESLF0ZB-lkp@intel.com/

All errors (new ones prefixed by >>):

   drivers/hv/hv_common.c: In function 'hv_sleep_notifiers_register':
>> drivers/hv/hv_common.c:944:57: error: macro "acpi_os_set_prepare_sleep" requires 3 arguments, but only 1 given
     944 |         acpi_os_set_prepare_sleep(&hv_acpi_sleep_handler);
         |                                                         ^
   In file included from drivers/hv/hv_common.c:16:
   include/linux/acpi.h:1165: note: macro "acpi_os_set_prepare_sleep" defined here
    1165 | #define acpi_os_set_prepare_sleep(func, pm1a_ctrl, pm1b_ctrl) do { } while (0)
         | 
>> drivers/hv/hv_common.c:944:9: error: 'acpi_os_set_prepare_sleep' undeclared (first use in this function); did you mean 'acpi_os_enter_sleep'?
     944 |         acpi_os_set_prepare_sleep(&hv_acpi_sleep_handler);
         |         ^~~~~~~~~~~~~~~~~~~~~~~~~
         |         acpi_os_enter_sleep
   drivers/hv/hv_common.c:944:9: note: each undeclared identifier is reported only once for each function it appears in
>> drivers/hv/hv_common.c:945:9: error: implicit declaration of function 'acpi_os_set_prepare_extended_sleep'; did you mean 'acpi_os_set_prepare_sleep'? [-Werror=implicit-function-declaration]
     945 |         acpi_os_set_prepare_extended_sleep(&hv_acpi_extended_sleep_handler);
         |         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
         |         acpi_os_set_prepare_sleep
   cc1: some warnings being treated as errors


vim +/acpi_os_set_prepare_sleep +944 drivers/hv/hv_common.c

   939	
   940	int hv_sleep_notifiers_register(void)
   941	{
   942		int ret;
   943	
 > 944		acpi_os_set_prepare_sleep(&hv_acpi_sleep_handler);
 > 945		acpi_os_set_prepare_extended_sleep(&hv_acpi_extended_sleep_handler);

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki

Re: [PATCH 2/2] hyperv: Enable clean shutdown for root partition with MSHV

[kernel test robot]

Hi Praveen,

kernel test robot noticed the following build warnings:

[auto build test WARNING on tip/x86/core]
[also build test WARNING on arnd-asm-generic/master soc/for-next linus/master v6.17 next-20251010]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Praveen-K-Paladugu/hyperv-Add-definitions-for-MSHV-sleep-state-configuration/20251010-122914
base:   tip/x86/core
patch link:    https://lore.kernel.org/r/20251009160501.6356-3-prapal%40linux.microsoft.com
patch subject: [PATCH 2/2] hyperv: Enable clean shutdown for root partition with MSHV
config: arm64-randconfig-003-20251011 (https://download.01.org/0day-ci/archive/20251011/202510111934.lcAG5ZAN-lkp@intel.com/config)
compiler: clang version 22.0.0git (https://github.com/llvm/llvm-project 39f292ffa13d7ca0d1edff27ac8fd55024bb4d19)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20251011/202510111934.lcAG5ZAN-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202510111934.lcAG5ZAN-lkp@intel.com/

All warnings (new ones prefixed by >>):

   drivers/hv/hv_common.c:944:50: error: too few arguments provided to function-like macro invocation
     944 |         acpi_os_set_prepare_sleep(&hv_acpi_sleep_handler);
         |                                                         ^
   include/linux/acpi.h:1165:9: note: macro 'acpi_os_set_prepare_sleep' defined here
    1165 | #define acpi_os_set_prepare_sleep(func, pm1a_ctrl, pm1b_ctrl) do { } while (0)
         |         ^
   drivers/hv/hv_common.c:944:2: error: use of undeclared identifier 'acpi_os_set_prepare_sleep'; did you mean 'acpi_os_enter_sleep'?
     944 |         acpi_os_set_prepare_sleep(&hv_acpi_sleep_handler);
         |         ^~~~~~~~~~~~~~~~~~~~~~~~~
         |         acpi_os_enter_sleep
   include/acpi/acpiosxf.h:326:13: note: 'acpi_os_enter_sleep' declared here
     326 | acpi_status acpi_os_enter_sleep(u8 sleep_state, u32 rega_value, u32 regb_value);
         |             ^
   drivers/hv/hv_common.c:945:2: error: call to undeclared function 'acpi_os_set_prepare_extended_sleep'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]
     945 |         acpi_os_set_prepare_extended_sleep(&hv_acpi_extended_sleep_handler);
         |         ^
>> drivers/hv/hv_common.c:944:2: warning: expression result unused [-Wunused-value]
     944 |         acpi_os_set_prepare_sleep(&hv_acpi_sleep_handler);
         |         ^~~~~~~~~~~~~~~~~~~~~~~~~
   1 warning and 3 errors generated.


vim +944 drivers/hv/hv_common.c

   939	
   940	int hv_sleep_notifiers_register(void)
   941	{
   942		int ret;
   943	
 > 944		acpi_os_set_prepare_sleep(&hv_acpi_sleep_handler);
 > 945		acpi_os_set_prepare_extended_sleep(&hv_acpi_extended_sleep_handler);

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki

Re: [PATCH 2/2] hyperv: Enable clean shutdown for root partition with MSHV

[Praveen K Paladugu]

On 10/9/2025 12:30 PM, Easwar Hariharan wrote:
> On 10/9/2025 8:58 AM, Praveen K Paladugu wrote:
>> This commit enables the root partition to perform a clean shutdown when
>> running with MSHV hypervisor.
> 
> No "This commit..." please
> 
>>
>> Signed-off-by: Praveen K Paladugu <prapal@linux.microsoft.com>
>> Co-developed-by: Anatol Belski <anbelski@linux.microsoft.com>
>> Signed-off-by: Anatol Belski <anbelski@linux.microsoft.com>
>> ---
>>   arch/x86/hyperv/hv_init.c      |   7 ++
>>   drivers/hv/hv_common.c         | 118 +++++++++++++++++++++++++++++++++
>>   include/asm-generic/mshyperv.h |   1 +
>>   3 files changed, 126 insertions(+)
>>
>> diff --git a/arch/x86/hyperv/hv_init.c b/arch/x86/hyperv/hv_init.c
>> index afdbda2dd7b7..57bd96671ead 100644
>> --- a/arch/x86/hyperv/hv_init.c
>> +++ b/arch/x86/hyperv/hv_init.c
>> @@ -510,6 +510,13 @@ void __init hyperv_init(void)
>>   		memunmap(src);
>>   
>>   		hv_remap_tsc_clocksource();
>> +		/*
>> +		 * The notifier registration might fail at various hops.
>> +		 * Corresponding error messages will land in dmesg. There is
>> +		 * otherwise nothing that can be specifically done to handle
>> +		 * failures here.
>> +		 */
>> +		(void)hv_sleep_notifiers_register();
>>   	} else {
>>   		hypercall_msr.guest_physical_address = vmalloc_to_pfn(hv_hypercall_pg);
>>   		wrmsrq(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64);
>> diff --git a/drivers/hv/hv_common.c b/drivers/hv/hv_common.c
>> index e109a620c83f..c5165deb5278 100644
>> --- a/drivers/hv/hv_common.c
>> +++ b/drivers/hv/hv_common.c
>> @@ -837,3 +837,121 @@ const char *hv_result_to_string(u64 status)
>>   	return "Unknown";
>>   }
>>   EXPORT_SYMBOL_GPL(hv_result_to_string);
>> +
>> +/*
>> + * Corresponding sleep states have to be initialized, in order for a subsequent
>> + * HVCALL_ENTER_SLEEP_STATE call to succeed. Currently only S5 state as per
>> + * ACPI 6.4 chapter 7.4.2 is relevant, while S1, S2 and S3 can be supported.
>> + *
>> + * ACPI should be initialized and should support S5 sleep state when this method
>> + * is called, so that, it can extract correct PM values and pass them to hv.
> 
> Nit: No need for this   ^ comma, i.e. "...when this method is called, so that it can..."
> 
>> + */
>> +static int hv_initialize_sleep_states(void)
>> +{
>> +	u64 status;
>> +	unsigned long flags;
>> +	struct hv_input_set_system_property *in;
>> +	acpi_status acpi_status;
>> +	u8 sleep_type_a, sleep_type_b;
>> +
>> +	if (!acpi_sleep_state_supported(ACPI_STATE_S5)) {
>> +		pr_err("%s: S5 sleep state not supported.\n", __func__);
>> +		return -ENODEV;
>> +	}
>> +
>> +	acpi_status = acpi_get_sleep_type_data(ACPI_STATE_S5,
>> +						&sleep_type_a, &sleep_type_b);
>> +	if (ACPI_FAILURE(acpi_status))
>> +		return -ENODEV;
>> +
>> +	local_irq_save(flags);
>> +	in = (struct hv_input_set_system_property *)(*this_cpu_ptr(
>> +		hyperv_pcpu_input_arg));
> 
> Other users don't have these casts, why is it necessary here?
> I didn't really need these casts. I will drop them in the next version.
>> +
>> +	in->property_id = HV_SYSTEM_PROPERTY_SLEEP_STATE;
>> +	in->set_sleep_state_info.sleep_state = HV_SLEEP_STATE_S5;
>> +	in->set_sleep_state_info.pm1a_slp_typ = sleep_type_a;
>> +	in->set_sleep_state_info.pm1b_slp_typ = sleep_type_b;
>> +
>> +	status = hv_do_hypercall(HVCALL_SET_SYSTEM_PROPERTY, in, NULL);
>> +	local_irq_restore(flags);
>> +
>> +	if (!hv_result_success(status)) {
>> +		pr_err("%s: %s\n", __func__, hv_result_to_string(status));
>> +		return hv_result_to_errno(status);
>> +	}
>> +
>> +	return 0;
>> +}
>> +
>> +static int hv_call_enter_sleep_state(u32 sleep_state)
>> +{
>> +	u64 status;
>> +	int ret;
>> +	unsigned long flags;
>> +	struct hv_input_enter_sleep_state *in;
>> +
>> +	ret = hv_initialize_sleep_states();
>> +	if (ret)
>> +		return ret;
>> +
>> +	local_irq_save(flags);
>> +	in = (struct hv_input_enter_sleep_state *)
>> +			(*this_cpu_ptr(hyperv_pcpu_input_arg));
>> +	in->sleep_state = (enum hv_sleep_state)sleep_state;
>> +
> 
> More casts...
> 
>> +	status = hv_do_hypercall(HVCALL_ENTER_SLEEP_STATE, in, NULL);
>> +	local_irq_restore(flags);
>> +
>> +	if (!hv_result_success(status)) {
>> +		pr_err("%s: %s\n", __func__, hv_result_to_string(status));
>> +		return hv_result_to_errno(status);
>> +	}
>> +
>> +	return 0;
>> +}
>> +
>> +static int hv_reboot_notifier_handler(struct notifier_block *this,
>> +				      unsigned long code, void *another)
>> +{
>> +	int ret = 0;
>> +
>> +	if (SYS_HALT == code || SYS_POWER_OFF == code)
> 
> Usually the variable is on the left of the comparison with the constant
> 
>> +		ret = hv_call_enter_sleep_state(HV_SLEEP_STATE_S5);
>> +
>> +	return ret ? NOTIFY_DONE : NOTIFY_OK;
>> +}
>> +
>> +static struct notifier_block hv_reboot_notifier = {
>> +	.notifier_call  = hv_reboot_notifier_handler,
>> +};
>> +
>> +static int hv_acpi_sleep_handler(u8 sleep_state, u32 pm1a_cnt, u32 pm1b_cnt)
>> +{
>> +	int ret = 0;
>> +
>> +	if (sleep_state == ACPI_STATE_S5)
>> +		ret = hv_call_enter_sleep_state(HV_SLEEP_STATE_S5);
>> +
>> +	return ret == 0 ? 1 : -1;
>> +}
>> +
>> +static int hv_acpi_extended_sleep_handler(u8 sleep_state, u32 val_a, u32 val_b)
>> +{
>> +	return hv_acpi_sleep_handler(sleep_state, val_a, val_b);
>> +}
>> +
>> +int hv_sleep_notifiers_register(void)
>> +{
>> +	int ret;
>> +
>> +	acpi_os_set_prepare_sleep(&hv_acpi_sleep_handler);
>> +	acpi_os_set_prepare_extended_sleep(&hv_acpi_extended_sleep_handler);
>> +
>> +	ret = register_reboot_notifier(&hv_reboot_notifier);
>> +	if (ret)
>> +		pr_err("%s: cannot register reboot notifier %d\n",
>> +			__func__, ret);
>> +
>> +	return ret;
>> +}
>> diff --git a/include/asm-generic/mshyperv.h b/include/asm-generic/mshyperv.h
>> index 64ba6bc807d9..903d089aba82 100644
>> --- a/include/asm-generic/mshyperv.h
>> +++ b/include/asm-generic/mshyperv.h
>> @@ -339,6 +339,7 @@ u64 hv_tdx_hypercall(u64 control, u64 param1, u64 param2);
>>   void hyperv_cleanup(void);
>>   bool hv_query_ext_cap(u64 cap_query);
>>   void hv_setup_dma_ops(struct device *dev, bool coherent);
>> +int hv_sleep_notifiers_register(void);

> 
> Does this still work when CONFIG_HYPERV = n, i.e. do we need a stub below? Also, this looks
> like it's only implemented for x86, so perhaps this declaration should be in arch/x86/include/asm/mshyperv.h
> instead of asm-generic?
As this sleep state data is configured using hypercalls, this code
does not work with CONFIG_HYPERV=n. I will investigate the correct 
header to use here and report back.

> 
>>   #else /* CONFIG_HYPERV */
>>   static inline void hv_identify_partition_type(void) {}
>>   static inline bool hv_is_hyperv_initialized(void) { return false; }
> 
> 
Thanks for the feedback. I will address all the nits along with above 
comments in next update.
-- 
Regards,
Praveen K Paladugu

Re: [PATCH 0/2] Add support for clean shutdown with MSHV

[Wei Liu]

On Thu, Oct 09, 2025 at 03:26:14PM -0700, Stanislav Kinsburskii wrote:
> On Thu, Oct 09, 2025 at 10:58:49AM -0500, Praveen K Paladugu wrote:
> > Add support for clean shutdown of the root partition when running on MSHV
> > hypervisor.
> > 
> > Praveen K Paladugu (2):
> >   hyperv: Add definitions for MSHV sleep state configuration
> >   hyperv: Enable clean shutdown for root partition with MSHV
> > 
> 
> There is no need to split this logic to two patches: the first one
> doesn't make sense without the second one, so it would be better to
> squash them.
> 

I would rather keep them separate. It is a bit easier to pick out only
the header changes that way.

Wei

> Thanks,
> Stanislav
> 
> >  arch/x86/hyperv/hv_init.c      |   7 ++
> >  drivers/hv/hv_common.c         | 118 +++++++++++++++++++++++++++++++++
> >  include/asm-generic/mshyperv.h |   1 +
> >  include/hyperv/hvgdk_mini.h    |   4 +-
> >  include/hyperv/hvhdk_mini.h    |  33 +++++++++
> >  5 files changed, 162 insertions(+), 1 deletion(-)
> > 
> > -- 
> > 2.51.0
> > 

Re: [PATCH 0/2] Add support for clean shutdown with MSHV

[Praveen K Paladugu]

On 10/13/2025 2:05 PM, Wei Liu wrote:
> On Thu, Oct 09, 2025 at 03:26:14PM -0700, Stanislav Kinsburskii wrote:
>> On Thu, Oct 09, 2025 at 10:58:49AM -0500, Praveen K Paladugu wrote:
>>> Add support for clean shutdown of the root partition when running on MSHV
>>> hypervisor.
>>>
>>> Praveen K Paladugu (2):
>>>    hyperv: Add definitions for MSHV sleep state configuration
>>>    hyperv: Enable clean shutdown for root partition with MSHV
>>>
>>
>> There is no need to split this logic to two patches: the first one
>> doesn't make sense without the second one, so it would be better to
>> squash them.
>>
> 
> I would rather keep them separate. It is a bit easier to pick out only
> the header changes that way.
> 
Ack.
> Wei
> 
>> Thanks,
>> Stanislav
>>
>>>   arch/x86/hyperv/hv_init.c      |   7 ++
>>>   drivers/hv/hv_common.c         | 118 +++++++++++++++++++++++++++++++++
>>>   include/asm-generic/mshyperv.h |   1 +
>>>   include/hyperv/hvgdk_mini.h    |   4 +-
>>>   include/hyperv/hvhdk_mini.h    |  33 +++++++++
>>>   5 files changed, 162 insertions(+), 1 deletion(-)
>>>
>>> -- 
>>> 2.51.0
>>>