From nobody Fri Dec 19 12:01:36 2025 Received: from linux.microsoft.com (linux.microsoft.com [13.77.154.182]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 2285E225A38; Thu, 9 Oct 2025 16:05:19 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=13.77.154.182 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760025920; cv=none; b=QD2ZVpDfAqoyBV8zIQDXccP9XlbZPlQ0F6OtXFPnwwXg4L88gAVenLI1/ugeiuebwdPBNrw/ca8iX624vLKC9KI/Jh4A2mI7caqwOBInElvD5mkHgURhVRGOsyupKXlPFi0bRjauhQknDRaP1z0VcJLTa3WfcOgRP+Ny+SzEqng= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760025920; c=relaxed/simple; bh=zyejt96P0FeNu60HKHr+d7rAco1Ux5PlVDsaxY1OCxY=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=Ow2RZnsBByZPhUAHefrowkGGUTWJv3sGLzcsN+k5Ek7Q0CplkGu3WUZ5nNXPviHf0Ubzv147JbzR0FS1c8y5PhHFf4mTIkQ/IhF7xBL2NoI8VivjJz4QCLyeUmMFgNTEiT1P6GbKYVxJzhHu/ugPdhSPN5fz4siMEYJCgUmA2fk= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.microsoft.com; spf=pass smtp.mailfrom=linux.microsoft.com; dkim=pass (1024-bit key) header.d=linux.microsoft.com header.i=@linux.microsoft.com header.b=kzWMB8Cg; arc=none smtp.client-ip=13.77.154.182 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.microsoft.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.microsoft.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.microsoft.com header.i=@linux.microsoft.com header.b="kzWMB8Cg" Received: from home (syn-072-191-074-189.res.spectrum.com [72.191.74.189]) by linux.microsoft.com (Postfix) with ESMTPSA id 79DEA211CE10; Thu, 9 Oct 2025 09:05:12 -0700 (PDT) DKIM-Filter: OpenDKIM Filter v2.11.0 linux.microsoft.com 79DEA211CE10 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.microsoft.com; s=default; t=1760025913; bh=HGtw/hLxsNqO+uJzT+Bj75q6zBOtKZdgbeh1YUgDHYE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=kzWMB8CgCvRPyoYFWk/Z05B2jwXwqg6Ns8EjbV9YbcZjdut2H3k5QTsGveLQVKOOh pVmLncEMk3gwkHRuVck8xm4lNupXLoKfG/H/QQOZdj5LSETuW5jERsNXpLczDk70tZ GN6SQ5Kl2KMAA1tL0yPjTLIWYdRgghBVy+7F3Xso= From: Praveen K Paladugu To: kys@microsoft.com, haiyangz@microsoft.com, wei.liu@kernel.org, decui@microsoft.com, tglx@linutronix.de, mingo@redhat.com, linux-hyperv@vger.kernel.org, linux-kernel@vger.kernel.org, bp@alien8.de, dave.hansen@linux.intel.com, x86@kernel.org, hpa@zytor.com, arnd@arndb.de Cc: anbelski@linux.microsoft.com, prapal@linux.microsoft.com Subject: [PATCH 2/2] hyperv: Enable clean shutdown for root partition with MSHV Date: Thu, 9 Oct 2025 10:58:51 -0500 Message-ID: <20251009160501.6356-3-prapal@linux.microsoft.com> X-Mailer: git-send-email 2.51.0 In-Reply-To: <20251009160501.6356-1-prapal@linux.microsoft.com> References: <20251009160501.6356-1-prapal@linux.microsoft.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" This commit enables the root partition to perform a clean shutdown when running with MSHV hypervisor. Signed-off-by: Praveen K Paladugu Co-developed-by: Anatol Belski Signed-off-by: Anatol Belski --- 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); =20 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 =3D 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 subse= quent + * 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 supporte= d. + * + * 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 h= v. + */ +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 =3D 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 =3D (struct hv_input_set_system_property *)(*this_cpu_ptr( + hyperv_pcpu_input_arg)); + + in->property_id =3D HV_SYSTEM_PROPERTY_SLEEP_STATE; + in->set_sleep_state_info.sleep_state =3D HV_SLEEP_STATE_S5; + in->set_sleep_state_info.pm1a_slp_typ =3D sleep_type_a; + in->set_sleep_state_info.pm1b_slp_typ =3D sleep_type_b; + + status =3D 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 =3D hv_initialize_sleep_states(); + if (ret) + return ret; + + local_irq_save(flags); + in =3D (struct hv_input_enter_sleep_state *) + (*this_cpu_ptr(hyperv_pcpu_input_arg)); + in->sleep_state =3D (enum hv_sleep_state)sleep_state; + + status =3D 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 =3D 0; + + if (SYS_HALT =3D=3D code || SYS_POWER_OFF =3D=3D code) + ret =3D hv_call_enter_sleep_state(HV_SLEEP_STATE_S5); + + return ret ? NOTIFY_DONE : NOTIFY_OK; +} + +static struct notifier_block hv_reboot_notifier =3D { + .notifier_call =3D hv_reboot_notifier_handler, +}; + +static int hv_acpi_sleep_handler(u8 sleep_state, u32 pm1a_cnt, u32 pm1b_cn= t) +{ + int ret =3D 0; + + if (sleep_state =3D=3D ACPI_STATE_S5) + ret =3D hv_call_enter_sleep_state(HV_SLEEP_STATE_S5); + + return ret =3D=3D 0 ? 1 : -1; +} + +static int hv_acpi_extended_sleep_handler(u8 sleep_state, u32 val_a, u32 v= al_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 =3D 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 param= 2); 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; } --=20 2.51.0