diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2021-09-01 18:25:20 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2021-09-01 18:25:20 -0700 |
commit | c07f191907e7d7e04034a2b9657a6bbf1355c60a (patch) | |
tree | 93940e9c54eeb8121f7bce5e89e652ec7bc6c6f7 /arch/arm64 | |
parent | 7c636d4d20f8c5acfbfbc60f326fddb0e1cf5daa (diff) | |
parent | 9d68cd9120e4e3af38f843e165631c323b86b4e4 (diff) | |
download | linux-c07f191907e7d7e04034a2b9657a6bbf1355c60a.tar.bz2 |
Merge tag 'hyperv-next-signed-20210831' of git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux
Pull hyperv updates from Wei Liu:
- make Hyper-V code arch-agnostic (Michael Kelley)
- fix sched_clock behaviour on Hyper-V (Ani Sinha)
- fix a fault when Linux runs as the root partition on MSHV (Praveen
Kumar)
- fix VSS driver (Vitaly Kuznetsov)
- cleanup (Sonia Sharma)
* tag 'hyperv-next-signed-20210831' of git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux:
hv_utils: Set the maximum packet size for VSS driver to the length of the receive buffer
Drivers: hv: Enable Hyper-V code to be built on ARM64
arm64: efi: Export screen_info
arm64: hyperv: Initialize hypervisor on boot
arm64: hyperv: Add panic handler
arm64: hyperv: Add Hyper-V hypercall and register access utilities
x86/hyperv: fix root partition faults when writing to VP assist page MSR
hv: hyperv.h: Remove unused inline functions
drivers: hv: Decouple Hyper-V clock/timer code from VMbus drivers
x86/hyperv: add comment describing TSC_INVARIANT_CONTROL MSR setting bit 0
Drivers: hv: Move Hyper-V misc functionality to arch-neutral code
Drivers: hv: Add arch independent default functions for some Hyper-V handlers
Drivers: hv: Make portions of Hyper-V init code be arch neutral
x86/hyperv: fix for unwanted manipulation of sched_clock when TSC marked unstable
asm-generic/hyperv: Add missing #include of nmi.h
Diffstat (limited to 'arch/arm64')
-rw-r--r-- | arch/arm64/Kbuild | 1 | ||||
-rw-r--r-- | arch/arm64/hyperv/Makefile | 2 | ||||
-rw-r--r-- | arch/arm64/hyperv/hv_core.c | 181 | ||||
-rw-r--r-- | arch/arm64/hyperv/mshyperv.c | 87 | ||||
-rw-r--r-- | arch/arm64/include/asm/hyperv-tlfs.h | 69 | ||||
-rw-r--r-- | arch/arm64/include/asm/mshyperv.h | 54 | ||||
-rw-r--r-- | arch/arm64/kernel/efi.c | 1 |
7 files changed, 395 insertions, 0 deletions
diff --git a/arch/arm64/Kbuild b/arch/arm64/Kbuild index 7b393cfec071..ea7ab4ca81f9 100644 --- a/arch/arm64/Kbuild +++ b/arch/arm64/Kbuild @@ -2,4 +2,5 @@ obj-y += kernel/ mm/ net/ obj-$(CONFIG_KVM) += kvm/ obj-$(CONFIG_XEN) += xen/ +obj-$(subst m,y,$(CONFIG_HYPERV)) += hyperv/ obj-$(CONFIG_CRYPTO) += crypto/ diff --git a/arch/arm64/hyperv/Makefile b/arch/arm64/hyperv/Makefile new file mode 100644 index 000000000000..87c31c001da9 --- /dev/null +++ b/arch/arm64/hyperv/Makefile @@ -0,0 +1,2 @@ +# SPDX-License-Identifier: GPL-2.0 +obj-y := hv_core.o mshyperv.o diff --git a/arch/arm64/hyperv/hv_core.c b/arch/arm64/hyperv/hv_core.c new file mode 100644 index 000000000000..b54c34793701 --- /dev/null +++ b/arch/arm64/hyperv/hv_core.c @@ -0,0 +1,181 @@ +// SPDX-License-Identifier: GPL-2.0 + +/* + * Low level utility routines for interacting with Hyper-V. + * + * Copyright (C) 2021, Microsoft, Inc. + * + * Author : Michael Kelley <mikelley@microsoft.com> + */ + +#include <linux/types.h> +#include <linux/export.h> +#include <linux/mm.h> +#include <linux/hyperv.h> +#include <linux/arm-smccc.h> +#include <linux/module.h> +#include <asm-generic/bug.h> +#include <asm/hyperv-tlfs.h> +#include <asm/mshyperv.h> + +/* + * hv_do_hypercall- Invoke the specified hypercall + */ +u64 hv_do_hypercall(u64 control, void *input, void *output) +{ + struct arm_smccc_res res; + u64 input_address; + u64 output_address; + + input_address = input ? virt_to_phys(input) : 0; + output_address = output ? virt_to_phys(output) : 0; + + arm_smccc_1_1_hvc(HV_FUNC_ID, control, + input_address, output_address, &res); + return res.a0; +} +EXPORT_SYMBOL_GPL(hv_do_hypercall); + +/* + * hv_do_fast_hypercall8 -- Invoke the specified hypercall + * with arguments in registers instead of physical memory. + * Avoids the overhead of virt_to_phys for simple hypercalls. + */ + +u64 hv_do_fast_hypercall8(u16 code, u64 input) +{ + struct arm_smccc_res res; + u64 control; + + control = (u64)code | HV_HYPERCALL_FAST_BIT; + + arm_smccc_1_1_hvc(HV_FUNC_ID, control, input, &res); + return res.a0; +} +EXPORT_SYMBOL_GPL(hv_do_fast_hypercall8); + +/* + * Set a single VP register to a 64-bit value. + */ +void hv_set_vpreg(u32 msr, u64 value) +{ + struct arm_smccc_res res; + + arm_smccc_1_1_hvc(HV_FUNC_ID, + HVCALL_SET_VP_REGISTERS | HV_HYPERCALL_FAST_BIT | + HV_HYPERCALL_REP_COMP_1, + HV_PARTITION_ID_SELF, + HV_VP_INDEX_SELF, + msr, + 0, + value, + 0, + &res); + + /* + * Something is fundamentally broken in the hypervisor if + * setting a VP register fails. There's really no way to + * continue as a guest VM, so panic. + */ + BUG_ON(!hv_result_success(res.a0)); +} +EXPORT_SYMBOL_GPL(hv_set_vpreg); + +/* + * Get the value of a single VP register. One version + * returns just 64 bits and another returns the full 128 bits. + * The two versions are separate to avoid complicating the + * calling sequence for the more frequently used 64 bit version. + */ + +void hv_get_vpreg_128(u32 msr, struct hv_get_vp_registers_output *result) +{ + struct arm_smccc_1_2_regs args; + struct arm_smccc_1_2_regs res; + + args.a0 = HV_FUNC_ID; + args.a1 = HVCALL_GET_VP_REGISTERS | HV_HYPERCALL_FAST_BIT | + HV_HYPERCALL_REP_COMP_1; + args.a2 = HV_PARTITION_ID_SELF; + args.a3 = HV_VP_INDEX_SELF; + args.a4 = msr; + + /* + * Use the SMCCC 1.2 interface because the results are in registers + * beyond X0-X3. + */ + arm_smccc_1_2_hvc(&args, &res); + + /* + * Something is fundamentally broken in the hypervisor if + * getting a VP register fails. There's really no way to + * continue as a guest VM, so panic. + */ + BUG_ON(!hv_result_success(res.a0)); + + result->as64.low = res.a6; + result->as64.high = res.a7; +} +EXPORT_SYMBOL_GPL(hv_get_vpreg_128); + +u64 hv_get_vpreg(u32 msr) +{ + struct hv_get_vp_registers_output output; + + hv_get_vpreg_128(msr, &output); + + return output.as64.low; +} +EXPORT_SYMBOL_GPL(hv_get_vpreg); + +/* + * hyperv_report_panic - report a panic to Hyper-V. This function uses + * the older version of the Hyper-V interface that admittedly doesn't + * pass enough information to be useful beyond just recording the + * occurrence of a panic. The parallel hv_kmsg_dump() uses the + * new interface that allows reporting 4 Kbytes of data, which is much + * more useful. Hyper-V on ARM64 always supports the newer interface, but + * we retain support for the older version because the sysadmin is allowed + * to disable the newer version via sysctl in case of information security + * concerns about the more verbose version. + */ +void hyperv_report_panic(struct pt_regs *regs, long err, bool in_die) +{ + static bool panic_reported; + u64 guest_id; + + /* Don't report a panic to Hyper-V if we're not going to panic */ + if (in_die && !panic_on_oops) + return; + + /* + * We prefer to report panic on 'die' chain as we have proper + * registers to report, but if we miss it (e.g. on BUG()) we need + * to report it on 'panic'. + * + * Calling code in the 'die' and 'panic' paths ensures that only + * one CPU is running this code, so no atomicity is needed. + */ + if (panic_reported) + return; + panic_reported = true; + + guest_id = hv_get_vpreg(HV_REGISTER_GUEST_OSID); + + /* + * Hyper-V provides the ability to store only 5 values. + * Pick the passed in error value, the guest_id, the PC, + * and the SP. + */ + hv_set_vpreg(HV_REGISTER_CRASH_P0, err); + hv_set_vpreg(HV_REGISTER_CRASH_P1, guest_id); + hv_set_vpreg(HV_REGISTER_CRASH_P2, regs->pc); + hv_set_vpreg(HV_REGISTER_CRASH_P3, regs->sp); + hv_set_vpreg(HV_REGISTER_CRASH_P4, 0); + + /* + * Let Hyper-V know there is crash data available + */ + hv_set_vpreg(HV_REGISTER_CRASH_CTL, HV_CRASH_CTL_CRASH_NOTIFY); +} +EXPORT_SYMBOL_GPL(hyperv_report_panic); diff --git a/arch/arm64/hyperv/mshyperv.c b/arch/arm64/hyperv/mshyperv.c new file mode 100644 index 000000000000..bbbe351e9045 --- /dev/null +++ b/arch/arm64/hyperv/mshyperv.c @@ -0,0 +1,87 @@ +// 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; + + /* + * Allow for a kernel built with CONFIG_HYPERV to be running in + * a non-Hyper-V environment, including on DT instead of ACPI. + * In such cases, do nothing and return success. + */ + if (acpi_disabled) + return 0; + + if (strncmp((char *)&acpi_gbl_FADT.hypervisor_id, "MsHyperV", 8)) + return 0; + + /* 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); diff --git a/arch/arm64/include/asm/hyperv-tlfs.h b/arch/arm64/include/asm/hyperv-tlfs.h new file mode 100644 index 000000000000..4d964a7f02ee --- /dev/null +++ b/arch/arm64/include/asm/hyperv-tlfs.h @@ -0,0 +1,69 @@ +/* SPDX-License-Identifier: GPL-2.0 */ + +/* + * This file contains definitions from the Hyper-V Hypervisor Top-Level + * Functional Specification (TLFS): + * https://docs.microsoft.com/en-us/virtualization/hyper-v-on-windows/reference/tlfs + * + * Copyright (C) 2021, Microsoft, Inc. + * + * Author : Michael Kelley <mikelley@microsoft.com> + */ + +#ifndef _ASM_HYPERV_TLFS_H +#define _ASM_HYPERV_TLFS_H + +#include <linux/types.h> + +/* + * All data structures defined in the TLFS that are shared between Hyper-V + * and a guest VM use Little Endian byte ordering. This matches the default + * byte ordering of Linux running on ARM64, so no special handling is required. + */ + +/* + * These Hyper-V registers provide information equivalent to the CPUID + * instruction on x86/x64. + */ +#define HV_REGISTER_HYPERVISOR_VERSION 0x00000100 /*CPUID 0x40000002 */ +#define HV_REGISTER_FEATURES 0x00000200 /*CPUID 0x40000003 */ +#define HV_REGISTER_ENLIGHTENMENTS 0x00000201 /*CPUID 0x40000004 */ + +/* + * Group C Features. See the asm-generic version of hyperv-tlfs.h + * for a description of Feature Groups. + */ + +/* Crash MSRs available */ +#define HV_FEATURE_GUEST_CRASH_MSR_AVAILABLE BIT(8) + +/* STIMER direct mode is available */ +#define HV_STIMER_DIRECT_MODE_AVAILABLE BIT(13) + +/* + * Synthetic register definitions equivalent to MSRs on x86/x64 + */ +#define HV_REGISTER_CRASH_P0 0x00000210 +#define HV_REGISTER_CRASH_P1 0x00000211 +#define HV_REGISTER_CRASH_P2 0x00000212 +#define HV_REGISTER_CRASH_P3 0x00000213 +#define HV_REGISTER_CRASH_P4 0x00000214 +#define HV_REGISTER_CRASH_CTL 0x00000215 + +#define HV_REGISTER_GUEST_OSID 0x00090002 +#define HV_REGISTER_VP_INDEX 0x00090003 +#define HV_REGISTER_TIME_REF_COUNT 0x00090004 +#define HV_REGISTER_REFERENCE_TSC 0x00090017 + +#define HV_REGISTER_SINT0 0x000A0000 +#define HV_REGISTER_SCONTROL 0x000A0010 +#define HV_REGISTER_SIEFP 0x000A0012 +#define HV_REGISTER_SIMP 0x000A0013 +#define HV_REGISTER_EOM 0x000A0014 + +#define HV_REGISTER_STIMER0_CONFIG 0x000B0000 +#define HV_REGISTER_STIMER0_COUNT 0x000B0001 + +#include <asm-generic/hyperv-tlfs.h> + +#endif diff --git a/arch/arm64/include/asm/mshyperv.h b/arch/arm64/include/asm/mshyperv.h new file mode 100644 index 000000000000..20070a847304 --- /dev/null +++ b/arch/arm64/include/asm/mshyperv.h @@ -0,0 +1,54 @@ +/* SPDX-License-Identifier: GPL-2.0 */ + +/* + * Linux-specific definitions for managing interactions with Microsoft's + * Hyper-V hypervisor. The definitions in this file are specific to + * the ARM64 architecture. See include/asm-generic/mshyperv.h for + * definitions are that architecture independent. + * + * Definitions that are specified in the Hyper-V Top Level Functional + * Spec (TLFS) should not go in this file, but should instead go in + * hyperv-tlfs.h. + * + * Copyright (C) 2021, Microsoft, Inc. + * + * Author : Michael Kelley <mikelley@microsoft.com> + */ + +#ifndef _ASM_MSHYPERV_H +#define _ASM_MSHYPERV_H + +#include <linux/types.h> +#include <linux/arm-smccc.h> +#include <asm/hyperv-tlfs.h> + +/* + * Declare calls to get and set Hyper-V VP register values on ARM64, which + * requires a hypercall. + */ + +void hv_set_vpreg(u32 reg, u64 value); +u64 hv_get_vpreg(u32 reg); +void hv_get_vpreg_128(u32 reg, struct hv_get_vp_registers_output *result); + +static inline void hv_set_register(unsigned int reg, u64 value) +{ + hv_set_vpreg(reg, value); +} + +static inline u64 hv_get_register(unsigned int reg) +{ + return hv_get_vpreg(reg); +} + +/* SMCCC hypercall parameters */ +#define HV_SMCCC_FUNC_NUMBER 1 +#define HV_FUNC_ID ARM_SMCCC_CALL_VAL( \ + ARM_SMCCC_STD_CALL, \ + ARM_SMCCC_SMC_64, \ + ARM_SMCCC_OWNER_VENDOR_HYP, \ + HV_SMCCC_FUNC_NUMBER) + +#include <asm-generic/mshyperv.h> + +#endif diff --git a/arch/arm64/kernel/efi.c b/arch/arm64/kernel/efi.c index fa02efb28e88..e1be6c429810 100644 --- a/arch/arm64/kernel/efi.c +++ b/arch/arm64/kernel/efi.c @@ -55,6 +55,7 @@ static __init pteval_t create_mapping_protection(efi_memory_desc_t *md) /* we will fill this structure from the stub, so don't put it in .bss */ struct screen_info screen_info __section(".data"); +EXPORT_SYMBOL(screen_info); int __init efi_create_mapping(struct mm_struct *mm, efi_memory_desc_t *md) { |