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[46.135.69.174]) by smtp.gmail.com with ESMTPSA id f65sm2374755wmg.45.2019.05.30.02.37.10 (version=TLS1_3 cipher=AEAD-AES256-GCM-SHA384 bits=256/256); Thu, 30 May 2019 02:37:11 -0700 (PDT) From: Vitaly Kuznetsov To: Michael Kelley Cc: "catalin.marinas\@arm.com" , "mark.rutland\@arm.com" , "will.deacon\@arm.com" , "marc.zyngier\@arm.com" , "linux-arm-kernel\@lists.infradead.org" , "gregkh\@linuxfoundation.org" , "linux-kernel\@vger.kernel.org" , "linux-hyperv\@vger.kernel.org" , "olaf\@aepfle.de" , "apw\@canonical.com" , "jasowang\@redhat.com" , "marcelo.cerri\@canonical.com" , Sunil Muthuswamy , KY Srinivasan Subject: Re: [PATCH v3 1/2] Drivers: hv: Create Hyper-V clocksource driver from existing clockevents code In-Reply-To: <1558969089-13204-2-git-send-email-mikelley@microsoft.com> References: <1558969089-13204-1-git-send-email-mikelley@microsoft.com> <1558969089-13204-2-git-send-email-mikelley@microsoft.com> Date: Thu, 30 May 2019 11:37:10 +0200 Message-ID: <87tvdcl1vd.fsf@vitty.brq.redhat.com> MIME-Version: 1.0 Content-Type: text/plain Sender: linux-hyperv-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-hyperv@vger.kernel.org Michael Kelley writes: > Clockevents code for Hyper-V synthetic timers is currently mixed > in with other Hyper-V code. Move the code to a Hyper-V specific > driver in the "clocksource" directory. Update the VMbus driver > to call initialization and cleanup routines since the Hyper-V > synthetic timers are not independently enumerated in ACPI. > > No behavior is changed and no new functionality is added. > > Suggested-by: Marc Zyngier > Signed-off-by: Michael Kelley > --- > MAINTAINERS | 2 + > arch/x86/include/asm/hyperv-tlfs.h | 6 ++ > arch/x86/kernel/cpu/mshyperv.c | 2 + > drivers/clocksource/Makefile | 1 + > drivers/clocksource/hyperv_timer.c | 191 +++++++++++++++++++++++++++++++++++++ > drivers/hv/Kconfig | 3 + > drivers/hv/hv.c | 156 +----------------------------- > drivers/hv/hyperv_vmbus.h | 3 - > drivers/hv/vmbus_drv.c | 42 ++++---- > include/clocksource/hyperv_timer.h | 27 ++++++ > 10 files changed, 258 insertions(+), 175 deletions(-) > create mode 100644 drivers/clocksource/hyperv_timer.c > create mode 100644 include/clocksource/hyperv_timer.h > > diff --git a/MAINTAINERS b/MAINTAINERS > index 992f1dd..cf2a5b7 100644 > --- a/MAINTAINERS > +++ b/MAINTAINERS > @@ -7294,6 +7294,7 @@ F: arch/x86/include/asm/trace/hyperv.h > F: arch/x86/include/asm/hyperv-tlfs.h > F: arch/x86/kernel/cpu/mshyperv.c > F: arch/x86/hyperv > +F: drivers/clocksource/hyperv_timer.c > F: drivers/hid/hid-hyperv.c > F: drivers/hv/ > F: drivers/input/serio/hyperv-keyboard.c > @@ -7304,6 +7305,7 @@ F: drivers/uio/uio_hv_generic.c > F: drivers/video/fbdev/hyperv_fb.c > F: drivers/iommu/hyperv_iommu.c > F: net/vmw_vsock/hyperv_transport.c > +F: include/clocksource/hyperv_timer.h > F: include/linux/hyperv.h > F: include/uapi/linux/hyperv.h > F: tools/hv/ > diff --git a/arch/x86/include/asm/hyperv-tlfs.h b/arch/x86/include/asm/hyperv-tlfs.h > index cdf44aa..af78cd7 100644 > --- a/arch/x86/include/asm/hyperv-tlfs.h > +++ b/arch/x86/include/asm/hyperv-tlfs.h > @@ -401,6 +401,12 @@ enum HV_GENERIC_SET_FORMAT { > #define HV_STATUS_INVALID_CONNECTION_ID 18 > #define HV_STATUS_INSUFFICIENT_BUFFERS 19 > > +/* > + * The Hyper-V TimeRefCount register and the TSC > + * page provide a guest VM clock with 100ns tick rate > + */ > +#define HV_CLOCK_HZ (NSEC_PER_SEC/100) > + > typedef struct _HV_REFERENCE_TSC_PAGE { > __u32 tsc_sequence; > __u32 res1; > diff --git a/arch/x86/kernel/cpu/mshyperv.c b/arch/x86/kernel/cpu/mshyperv.c > index faae611..b18ede4 100644 > --- a/arch/x86/kernel/cpu/mshyperv.c > +++ b/arch/x86/kernel/cpu/mshyperv.c > @@ -21,6 +21,7 @@ > #include > #include > #include > +#include > #include > #include > #include > @@ -84,6 +85,7 @@ __visible void __irq_entry hv_stimer0_vector_handler(struct pt_regs *regs) > inc_irq_stat(hyperv_stimer0_count); > if (hv_stimer0_handler) > hv_stimer0_handler(); > + add_interrupt_randomness(HYPERV_STIMER0_VECTOR, 0); > ack_APIC_irq(); > > exiting_irq(); > diff --git a/drivers/clocksource/Makefile b/drivers/clocksource/Makefile > index 236858f..2b65c5f 100644 > --- a/drivers/clocksource/Makefile > +++ b/drivers/clocksource/Makefile > @@ -84,3 +84,4 @@ obj-$(CONFIG_ATCPIT100_TIMER) += timer-atcpit100.o > obj-$(CONFIG_RISCV_TIMER) += timer-riscv.o > obj-$(CONFIG_CSKY_MP_TIMER) += timer-mp-csky.o > obj-$(CONFIG_GX6605S_TIMER) += timer-gx6605s.o > +obj-$(CONFIG_HYPERV_TIMER) += hyperv_timer.o > diff --git a/drivers/clocksource/hyperv_timer.c b/drivers/clocksource/hyperv_timer.c > new file mode 100644 > index 0000000..30615f3 > --- /dev/null > +++ b/drivers/clocksource/hyperv_timer.c > @@ -0,0 +1,191 @@ > +// SPDX-License-Identifier: GPL-2.0 > + > +/* > + * Clocksource driver for the synthetic counter and timers > + * provided by the Hyper-V hypervisor to guest VMs, as described > + * in the Hyper-V Top Level Functional Spec (TLFS). This driver > + * is instruction set architecture independent. > + * > + * Copyright (C) 2019, Microsoft, Inc. > + * > + * Author: Michael Kelley > + */ > + > +#include > +#include > +#include > +#include > +#include > +#include > +#include > + > +static struct clock_event_device __percpu *hv_clock_event; > + > +/* > + * If false, we're using the old mechanism for stimer0 interrupts > + * where it sends a VMbus message when it expires. The old > + * mechanism is used when running on older versions of Hyper-V > + * that don't support Direct Mode. While Hyper-V provides > + * four stimer's per CPU, Linux uses only stimer0. > + */ > +static bool direct_mode_enabled; > + > +static int stimer0_irq; > +static int stimer0_vector; > +static int stimer0_message_sint; > + > +/* > + * ISR for when stimer0 is operating in Direct Mode. Direct Mode > + * does not use VMbus or any VMbus messages, so process here and not > + * in the VMbus driver code. > + */ > +void hv_stimer0_isr(void) > +{ > + struct clock_event_device *ce; > + > + ce = this_cpu_ptr(hv_clock_event); > + ce->event_handler(ce); > +} > +EXPORT_SYMBOL_GPL(hv_stimer0_isr); > + > +static int hv_ce_set_next_event(unsigned long delta, > + struct clock_event_device *evt) > +{ > + u64 current_tick; > + > + WARN_ON(!clockevent_state_oneshot(evt)); > + > + current_tick = hyperv_cs->read(NULL); > + current_tick += delta; > + hv_init_timer(0, current_tick); > + return 0; > +} > + > +static int hv_ce_shutdown(struct clock_event_device *evt) > +{ > + hv_init_timer(0, 0); > + hv_init_timer_config(0, 0); > + if (direct_mode_enabled) > + hv_disable_stimer0_percpu_irq(stimer0_irq); > + > + return 0; > +} > + > +static int hv_ce_set_oneshot(struct clock_event_device *evt) > +{ > + union hv_stimer_config timer_cfg; > + > + timer_cfg.as_uint64 = 0; > + timer_cfg.enable = 1; > + timer_cfg.auto_enable = 1; > + if (direct_mode_enabled) { > + /* > + * When it expires, the timer will directly interrupt > + * on the specified hardware vector/IRQ. > + */ > + timer_cfg.direct_mode = 1; > + timer_cfg.apic_vector = stimer0_vector; > + hv_enable_stimer0_percpu_irq(stimer0_irq); > + } else { > + /* > + * When it expires, the timer will generate a VMbus message, > + * to be handled by the normal VMbus interrupt handler. > + */ > + timer_cfg.direct_mode = 0; > + timer_cfg.sintx = stimer0_message_sint; > + } > + hv_init_timer_config(0, timer_cfg.as_uint64); > + return 0; > +} > + > +/* > + * hv_stimer_init - Per-cpu initialization of the clockevent > + */ > +int hv_stimer_init(unsigned int cpu) > +{ > + struct clock_event_device *ce; > + > + if (ms_hyperv.features & HV_MSR_SYNTIMER_AVAILABLE) { > + ce = per_cpu_ptr(hv_clock_event, cpu); > + ce->name = "Hyper-V clockevent"; > + ce->features = CLOCK_EVT_FEAT_ONESHOT; > + ce->cpumask = cpumask_of(cpu); > + ce->rating = 1000; > + ce->set_state_shutdown = hv_ce_shutdown; > + ce->set_state_oneshot = hv_ce_set_oneshot; > + ce->set_next_event = hv_ce_set_next_event; > + > + clockevents_config_and_register(ce, > + HV_CLOCK_HZ, > + HV_MIN_DELTA_TICKS, > + HV_MAX_MAX_DELTA_TICKS); > + } > + return 0; > +} > +EXPORT_SYMBOL_GPL(hv_stimer_init); > + > +/* > + * hv_stimer_cleanup - Per-cpu cleanup of the clockevent > + */ > +int hv_stimer_cleanup(unsigned int cpu) > +{ > + struct clock_event_device *ce; > + > + /* Turn off clockevent device */ > + if (ms_hyperv.features & HV_MSR_SYNTIMER_AVAILABLE) { > + ce = per_cpu_ptr(hv_clock_event, cpu); > + clockevents_unbind_device(ce, cpu); > + hv_ce_shutdown(ce); > + } > + > + return 0; > +} > +EXPORT_SYMBOL_GPL(hv_stimer_cleanup); > + > +/* hv_stimer_alloc - Global initialization of the clockevent and stimer0 */ > +int hv_stimer_alloc(int sint) > +{ > + hv_clock_event = alloc_percpu(struct clock_event_device); > + if (!hv_clock_event) > + return -ENOMEM; > + > + direct_mode_enabled = ms_hyperv.misc_features & > + HV_STIMER_DIRECT_MODE_AVAILABLE; > + if (direct_mode_enabled && > + hv_setup_stimer0_irq(&stimer0_irq, &stimer0_vector, > + hv_stimer0_isr)) { > + free_percpu(hv_clock_event); > + return -EINVAL; > + } > + > + stimer0_message_sint = sint; > + return 0; > +} > +EXPORT_SYMBOL_GPL(hv_stimer_alloc); > + > +/* hv_stimer_free - Free global resources allocated by hv_stimer_alloc() */ > +void hv_stimer_free(void) > +{ > + if (direct_mode_enabled) > + hv_remove_stimer0_irq(stimer0_irq); > + free_percpu(hv_clock_event); > +} > +EXPORT_SYMBOL_GPL(hv_stimer_free); > + > +/* > + * Do a global cleanup of clockevents for the cases of kexec and > + * vmbus exit > + */ > +void hv_stimer_global_cleanup(void) > +{ > + int cpu; > + struct clock_event_device *ce; > + > + if (ms_hyperv.features & HV_MSR_SYNTIMER_AVAILABLE) > + for_each_present_cpu(cpu) { > + ce = per_cpu_ptr(hv_clock_event, cpu); > + clockevents_unbind_device(ce, cpu); > + } > + hv_stimer_free(); > +} > +EXPORT_SYMBOL_GPL(hv_stimer_global_cleanup); > diff --git a/drivers/hv/Kconfig b/drivers/hv/Kconfig > index 1c1a251..c423e57 100644 > --- a/drivers/hv/Kconfig > +++ b/drivers/hv/Kconfig > @@ -10,6 +10,9 @@ config HYPERV > Select this option to run Linux as a Hyper-V client operating > system. > > +config HYPERV_TIMER > + def_bool HYPERV > + > config HYPERV_TSCPAGE > def_bool HYPERV && X86_64 > > diff --git a/drivers/hv/hv.c b/drivers/hv/hv.c > index 4565302..bd6452f 100644 > --- a/drivers/hv/hv.c > +++ b/drivers/hv/hv.c > @@ -29,6 +29,7 @@ > #include > #include > #include (very minor nit, just an idea for future cleanup): I think we can throw away #include #include now. > +#include > #include > #include "hyperv_vmbus.h" > > @@ -36,21 +37,6 @@ > struct hv_context hv_context; > > /* > - * If false, we're using the old mechanism for stimer0 interrupts > - * where it sends a VMbus message when it expires. The old > - * mechanism is used when running on older versions of Hyper-V > - * that don't support Direct Mode. While Hyper-V provides > - * four stimer's per CPU, Linux uses only stimer0. > - */ > -static bool direct_mode_enabled; > -static int stimer0_irq; > -static int stimer0_vector; > - > -#define HV_TIMER_FREQUENCY (10 * 1000 * 1000) /* 100ns period */ > -#define HV_MAX_MAX_DELTA_TICKS 0xffffffff > -#define HV_MIN_DELTA_TICKS 1 > - > -/* > * hv_init - Main initialization routine. > * > * This routine must be called before any other routines in here are called > @@ -60,9 +46,6 @@ int hv_init(void) > hv_context.cpu_context = alloc_percpu(struct hv_per_cpu_context); > if (!hv_context.cpu_context) > return -ENOMEM; > - > - direct_mode_enabled = ms_hyperv.misc_features & > - HV_STIMER_DIRECT_MODE_AVAILABLE; > return 0; > } > > @@ -101,89 +84,6 @@ int hv_post_message(union hv_connection_id connection_id, > return status & 0xFFFF; > } > > -/* > - * ISR for when stimer0 is operating in Direct Mode. Direct Mode > - * does not use VMbus or any VMbus messages, so process here and not > - * in the VMbus driver code. > - */ > - > -static void hv_stimer0_isr(void) > -{ > - struct hv_per_cpu_context *hv_cpu; > - > - hv_cpu = this_cpu_ptr(hv_context.cpu_context); > - hv_cpu->clk_evt->event_handler(hv_cpu->clk_evt); > - add_interrupt_randomness(stimer0_vector, 0); > -} > - > -static int hv_ce_set_next_event(unsigned long delta, > - struct clock_event_device *evt) > -{ > - u64 current_tick; > - > - WARN_ON(!clockevent_state_oneshot(evt)); > - > - current_tick = hyperv_cs->read(NULL); > - current_tick += delta; > - hv_init_timer(0, current_tick); > - return 0; > -} > - > -static int hv_ce_shutdown(struct clock_event_device *evt) > -{ > - hv_init_timer(0, 0); > - hv_init_timer_config(0, 0); > - if (direct_mode_enabled) > - hv_disable_stimer0_percpu_irq(stimer0_irq); > - > - return 0; > -} > - > -static int hv_ce_set_oneshot(struct clock_event_device *evt) > -{ > - union hv_stimer_config timer_cfg; > - > - timer_cfg.as_uint64 = 0; > - timer_cfg.enable = 1; > - timer_cfg.auto_enable = 1; > - if (direct_mode_enabled) { > - /* > - * When it expires, the timer will directly interrupt > - * on the specified hardware vector/IRQ. > - */ > - timer_cfg.direct_mode = 1; > - timer_cfg.apic_vector = stimer0_vector; > - hv_enable_stimer0_percpu_irq(stimer0_irq); > - } else { > - /* > - * When it expires, the timer will generate a VMbus message, > - * to be handled by the normal VMbus interrupt handler. > - */ > - timer_cfg.direct_mode = 0; > - timer_cfg.sintx = VMBUS_MESSAGE_SINT; > - } > - hv_init_timer_config(0, timer_cfg.as_uint64); > - return 0; > -} > - > -static void hv_init_clockevent_device(struct clock_event_device *dev, int cpu) > -{ > - dev->name = "Hyper-V clockevent"; > - dev->features = CLOCK_EVT_FEAT_ONESHOT; > - dev->cpumask = cpumask_of(cpu); > - dev->rating = 1000; > - /* > - * Avoid settint dev->owner = THIS_MODULE deliberately as doing so will > - * result in clockevents_config_and_register() taking additional > - * references to the hv_vmbus module making it impossible to unload. > - */ > - > - dev->set_state_shutdown = hv_ce_shutdown; > - dev->set_state_oneshot = hv_ce_set_oneshot; > - dev->set_next_event = hv_ce_set_next_event; > -} > - > - > int hv_synic_alloc(void) > { > int cpu; > @@ -212,14 +112,6 @@ int hv_synic_alloc(void) > tasklet_init(&hv_cpu->msg_dpc, > vmbus_on_msg_dpc, (unsigned long) hv_cpu); > > - hv_cpu->clk_evt = kzalloc(sizeof(struct clock_event_device), > - GFP_KERNEL); > - if (hv_cpu->clk_evt == NULL) { > - pr_err("Unable to allocate clock event device\n"); > - goto err; > - } > - hv_init_clockevent_device(hv_cpu->clk_evt, cpu); > - > hv_cpu->synic_message_page = > (void *)get_zeroed_page(GFP_ATOMIC); > if (hv_cpu->synic_message_page == NULL) { > @@ -242,11 +134,6 @@ int hv_synic_alloc(void) > INIT_LIST_HEAD(&hv_cpu->chan_list); > } > > - if (direct_mode_enabled && > - hv_setup_stimer0_irq(&stimer0_irq, &stimer0_vector, > - hv_stimer0_isr)) > - goto err; > - > return 0; > err: > /* > @@ -265,7 +152,6 @@ void hv_synic_free(void) > struct hv_per_cpu_context *hv_cpu > = per_cpu_ptr(hv_context.cpu_context, cpu); > > - kfree(hv_cpu->clk_evt); > free_page((unsigned long)hv_cpu->synic_event_page); > free_page((unsigned long)hv_cpu->synic_message_page); > free_page((unsigned long)hv_cpu->post_msg_page); > @@ -324,36 +210,9 @@ int hv_synic_init(unsigned int cpu) > > hv_set_synic_state(sctrl.as_uint64); > > - /* > - * Register the per-cpu clockevent source. > - */ > - if (ms_hyperv.features & HV_MSR_SYNTIMER_AVAILABLE) > - clockevents_config_and_register(hv_cpu->clk_evt, > - HV_TIMER_FREQUENCY, > - HV_MIN_DELTA_TICKS, > - HV_MAX_MAX_DELTA_TICKS); > - return 0; > -} > - > -/* > - * hv_synic_clockevents_cleanup - Cleanup clockevent devices > - */ > -void hv_synic_clockevents_cleanup(void) > -{ > - int cpu; > + hv_stimer_init(cpu); > > - if (!(ms_hyperv.features & HV_MSR_SYNTIMER_AVAILABLE)) > - return; > - > - if (direct_mode_enabled) > - hv_remove_stimer0_irq(stimer0_irq); > - > - for_each_present_cpu(cpu) { > - struct hv_per_cpu_context *hv_cpu > - = per_cpu_ptr(hv_context.cpu_context, cpu); > - > - clockevents_unbind_device(hv_cpu->clk_evt, cpu); > - } > + return 0; > } > > /* > @@ -401,14 +260,7 @@ int hv_synic_cleanup(unsigned int cpu) > if (channel_found && vmbus_connection.conn_state == CONNECTED) > return -EBUSY; > > - /* Turn off clockevent device */ > - if (ms_hyperv.features & HV_MSR_SYNTIMER_AVAILABLE) { > - struct hv_per_cpu_context *hv_cpu > - = this_cpu_ptr(hv_context.cpu_context); > - > - clockevents_unbind_device(hv_cpu->clk_evt, cpu); > - hv_ce_shutdown(hv_cpu->clk_evt); > - } > + hv_stimer_cleanup(cpu); > > hv_get_synint_state(VMBUS_MESSAGE_SINT, shared_sint.as_uint64); > > diff --git a/drivers/hv/hyperv_vmbus.h b/drivers/hv/hyperv_vmbus.h > index e5467b8..a8f8aee 100644 > --- a/drivers/hv/hyperv_vmbus.h > +++ b/drivers/hv/hyperv_vmbus.h > @@ -151,7 +151,6 @@ struct hv_per_cpu_context { > * per-cpu list of the channels based on their CPU affinity. > */ > struct list_head chan_list; > - struct clock_event_device *clk_evt; > }; > > struct hv_context { > @@ -189,8 +188,6 @@ extern int hv_post_message(union hv_connection_id connection_id, > > extern int hv_synic_cleanup(unsigned int cpu); > > -extern void hv_synic_clockevents_cleanup(void); > - > /* Interface */ > > void hv_ringbuffer_pre_init(struct vmbus_channel *channel); > diff --git a/drivers/hv/vmbus_drv.c b/drivers/hv/vmbus_drv.c > index 1cb9408..89aca5d 100644 > --- a/drivers/hv/vmbus_drv.c > +++ b/drivers/hv/vmbus_drv.c > @@ -43,6 +43,7 @@ > #include > #include > #include > +#include > #include "hyperv_vmbus.h" > > struct vmbus_dynid { > @@ -968,17 +969,6 @@ static void vmbus_onmessage_work(struct work_struct *work) > kfree(ctx); > } > > -static void hv_process_timer_expiration(struct hv_message *msg, > - struct hv_per_cpu_context *hv_cpu) > -{ > - struct clock_event_device *dev = hv_cpu->clk_evt; > - > - if (dev->event_handler) > - dev->event_handler(dev); > - > - vmbus_signal_eom(msg, HVMSG_TIMER_EXPIRED); > -} > - > void vmbus_on_msg_dpc(unsigned long data) > { > struct hv_per_cpu_context *hv_cpu = (void *)data; > @@ -1172,9 +1162,10 @@ static void vmbus_isr(void) > > /* Check if there are actual msgs to be processed */ > if (msg->header.message_type != HVMSG_NONE) { > - if (msg->header.message_type == HVMSG_TIMER_EXPIRED) > - hv_process_timer_expiration(msg, hv_cpu); > - else > + if (msg->header.message_type == HVMSG_TIMER_EXPIRED) { > + hv_stimer0_isr(); > + vmbus_signal_eom(msg, HVMSG_TIMER_EXPIRED); > + } else > tasklet_schedule(&hv_cpu->msg_dpc); > } > > @@ -1276,14 +1267,19 @@ static int vmbus_bus_init(void) > ret = hv_synic_alloc(); > if (ret) > goto err_alloc; > + > + ret = hv_stimer_alloc(VMBUS_MESSAGE_SINT); > + if (ret < 0) > + goto err_alloc; > + > /* > - * Initialize the per-cpu interrupt state and > - * connect to the host. > + * Initialize the per-cpu interrupt state and stimer state. > + * Then connect to the host. > */ > ret = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "hyperv/vmbus:online", > hv_synic_init, hv_synic_cleanup); > if (ret < 0) > - goto err_alloc; > + goto err_cpuhp; > hyperv_cpuhp_online = ret; > > ret = vmbus_connect(); > @@ -1331,6 +1327,8 @@ static int vmbus_bus_init(void) > > err_connect: > cpuhp_remove_state(hyperv_cpuhp_online); > +err_cpuhp: > + hv_stimer_free(); > err_alloc: > hv_synic_free(); > hv_remove_vmbus_irq(); > @@ -2077,7 +2075,7 @@ static int vmbus_acpi_add(struct acpi_device *device) > > static void hv_kexec_handler(void) > { > - hv_synic_clockevents_cleanup(); > + hv_stimer_global_cleanup(); > vmbus_initiate_unload(false); > vmbus_connection.conn_state = DISCONNECTED; > /* Make sure conn_state is set as hv_synic_cleanup checks for it */ > @@ -2088,6 +2086,8 @@ static void hv_kexec_handler(void) > > static void hv_crash_handler(struct pt_regs *regs) > { > + int cpu; > + > vmbus_initiate_unload(true); > /* > * In crash handler we can't schedule synic cleanup for all CPUs, > @@ -2095,7 +2095,9 @@ static void hv_crash_handler(struct pt_regs *regs) > * for kdump. > */ > vmbus_connection.conn_state = DISCONNECTED; > - hv_synic_cleanup(smp_processor_id()); > + cpu = smp_processor_id(); > + hv_stimer_cleanup(cpu); > + hv_synic_cleanup(cpu); > hyperv_cleanup(); > }; > > @@ -2144,7 +2146,7 @@ static void __exit vmbus_exit(void) > hv_remove_kexec_handler(); > hv_remove_crash_handler(); > vmbus_connection.conn_state = DISCONNECTED; > - hv_synic_clockevents_cleanup(); > + hv_stimer_global_cleanup(); > vmbus_disconnect(); > hv_remove_vmbus_irq(); > for_each_online_cpu(cpu) { > diff --git a/include/clocksource/hyperv_timer.h b/include/clocksource/hyperv_timer.h > new file mode 100644 > index 0000000..ba5dc17 > --- /dev/null > +++ b/include/clocksource/hyperv_timer.h > @@ -0,0 +1,27 @@ > +/* SPDX-License-Identifier: GPL-2.0 */ > + > +/* > + * Definitions for the clocksource provided by the Hyper-V > + * hypervisor to guest VMs, as described in the Hyper-V Top > + * Level Functional Spec (TLFS). > + * > + * Copyright (C) 2019, Microsoft, Inc. > + * > + * Author: Michael Kelley > + */ > + > +#ifndef __CLKSOURCE_HYPERV_TIMER_H > +#define __CLKSOURCE_HYPERV_TIMER_H > + > +#define HV_MAX_MAX_DELTA_TICKS 0xffffffff > +#define HV_MIN_DELTA_TICKS 1 > + > +/* Routines called by the VMbus driver */ > +extern int hv_stimer_alloc(int sint); > +extern void hv_stimer_free(void); > +extern int hv_stimer_init(unsigned int cpu); > +extern int hv_stimer_cleanup(unsigned int cpu); > +extern void hv_stimer_global_cleanup(void); > +extern void hv_stimer0_isr(void); > + > +#endif Reviewed-by: Vitaly Kuznetsov -- Vitaly