diff options
Diffstat (limited to 'arch/x86/kernel/cpu/mshyperv.c')
| -rw-r--r-- | arch/x86/kernel/cpu/mshyperv.c | 38 |
1 files changed, 16 insertions, 22 deletions
diff --git a/arch/x86/kernel/cpu/mshyperv.c b/arch/x86/kernel/cpu/mshyperv.c index c890d67a64ad..e095c28d27ae 100644 --- a/arch/x86/kernel/cpu/mshyperv.c +++ b/arch/x86/kernel/cpu/mshyperv.c @@ -17,7 +17,6 @@ #include <linux/irq.h> #include <linux/kexec.h> #include <linux/i8253.h> -#include <linux/panic_notifier.h> #include <linux/random.h> #include <asm/processor.h> #include <asm/hypervisor.h> @@ -36,10 +35,7 @@ /* Is Linux running as the root partition? */ bool hv_root_partition; -EXPORT_SYMBOL_GPL(hv_root_partition); - struct ms_hyperv_info ms_hyperv; -EXPORT_SYMBOL_GPL(ms_hyperv); #if IS_ENABLED(CONFIG_HYPERV) static void (*vmbus_handler)(void); @@ -65,14 +61,12 @@ void hv_setup_vmbus_handler(void (*handler)(void)) { vmbus_handler = handler; } -EXPORT_SYMBOL_GPL(hv_setup_vmbus_handler); void hv_remove_vmbus_handler(void) { /* We have no way to deallocate the interrupt gate */ vmbus_handler = NULL; } -EXPORT_SYMBOL_GPL(hv_remove_vmbus_handler); /* * Routines to do per-architecture handling of stimer0 @@ -107,25 +101,21 @@ void hv_setup_kexec_handler(void (*handler)(void)) { hv_kexec_handler = handler; } -EXPORT_SYMBOL_GPL(hv_setup_kexec_handler); void hv_remove_kexec_handler(void) { hv_kexec_handler = NULL; } -EXPORT_SYMBOL_GPL(hv_remove_kexec_handler); void hv_setup_crash_handler(void (*handler)(struct pt_regs *regs)) { hv_crash_handler = handler; } -EXPORT_SYMBOL_GPL(hv_setup_crash_handler); void hv_remove_crash_handler(void) { hv_crash_handler = NULL; } -EXPORT_SYMBOL_GPL(hv_remove_crash_handler); #ifdef CONFIG_KEXEC_CORE static void hv_machine_shutdown(void) @@ -335,16 +325,6 @@ static void __init ms_hyperv_init_platform(void) ms_hyperv.nested_features); } - /* - * Hyper-V expects to get crash register data or kmsg when - * crash enlightment is available and system crashes. Set - * crash_kexec_post_notifiers to be true to make sure that - * calling crash enlightment interface before running kdump - * kernel. - */ - if (ms_hyperv.misc_features & HV_FEATURE_GUEST_CRASH_MSR_AVAILABLE) - crash_kexec_post_notifiers = true; - #ifdef CONFIG_X86_LOCAL_APIC if (ms_hyperv.features & HV_ACCESS_FREQUENCY_MSRS && ms_hyperv.misc_features & HV_FEATURE_FREQUENCY_MSRS_AVAILABLE) { @@ -373,10 +353,17 @@ static void __init ms_hyperv_init_platform(void) machine_ops.crash_shutdown = hv_machine_crash_shutdown; #endif if (ms_hyperv.features & HV_ACCESS_TSC_INVARIANT) { + /* + * Writing to synthetic MSR 0x40000118 updates/changes the + * guest visible CPUIDs. Setting bit 0 of this MSR enables + * guests to report invariant TSC feature through CPUID + * instruction, CPUID 0x800000007/EDX, bit 8. See code in + * early_init_intel() where this bit is examined. The + * setting of this MSR bit should happen before init_intel() + * is called. + */ wrmsrl(HV_X64_MSR_TSC_INVARIANT_CONTROL, 0x1); setup_force_cpu_cap(X86_FEATURE_TSC_RELIABLE); - } else { - mark_tsc_unstable("running on Hyper-V"); } /* @@ -437,6 +424,13 @@ static void __init ms_hyperv_init_platform(void) /* Register Hyper-V specific clocksource */ hv_init_clocksource(); #endif + /* + * TSC should be marked as unstable only after Hyper-V + * clocksource has been initialized. This ensures that the + * stability of the sched_clock is not altered. + */ + if (!(ms_hyperv.features & HV_ACCESS_TSC_INVARIANT)) + mark_tsc_unstable("running on Hyper-V"); } static bool __init ms_hyperv_x2apic_available(void) |