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; }
--
2.51.0Hi 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
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
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; }
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; }
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
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