Re: [PATCH v13 6/8] introduce a new qom device to deal with panicked event

Paolo Bonzini
2013-03-04T09:46:06Z

Il 28/02/2013 13:13, Hu Tao ha scritto:
> If the target is x86/x86_64, the guest's kernel will write 0x01 to the
> port KVM_PV_EVENT_PORT when it is panciked. This patch introduces a new
> qom device kvm_pv_ioport to listen this I/O port, and deal with panicked
> event according to panicked_action's value. The possible actions are:
> 1. emit QEVENT_GUEST_PANICKED only
> 2. emit QEVENT_GUEST_PANICKED and pause the guest
> 3. emit QEVENT_GUEST_PANICKED and poweroff the guest
> 4. emit QEVENT_GUEST_PANICKED and reset the guest
>
> I/O ports does not work for some targets(for example: s390). And you
> can implement another qom device, and include it's code into pv_event.c
> for such target.
>
> Note: if we emit QEVENT_GUEST_PANICKED only, and the management
> application does not receive this event(the management may not
> run when the event is emitted), the management won't know the
> guest is panicked.

There's nothing KVM-specific about this, no?

Let's call the device hw/pvevent.c, and the device isa-pvevent like
isa-debugcon and isa-debugexit.

Paolo

> Signed-off-by: Wen Congyang <wency@cn.fujitsu.com>
> Signed-off-by: Hu Tao <hutao@cn.fujitsu.com>
> ---
> hw/kvm/Makefile.objs | 2 +-
> hw/kvm/pv_event.c | 198 +++++++++++++++++++++++++++++++++++++++++++++++++++
> hw/pc_piix.c | 5 ++
> include/sysemu/kvm.h | 2 +
> kvm-stub.c | 4 ++
> 5 files changed, 210 insertions(+), 1 deletion(-)
> create mode 100644 hw/kvm/pv_event.c
>
> diff --git a/hw/kvm/Makefile.objs b/hw/kvm/Makefile.objs
> index f620d7f..cf93199 100644
> --- a/hw/kvm/Makefile.objs
> +++ b/hw/kvm/Makefile.objs
> @@ -1 +1 @@
> -obj-$(CONFIG_KVM) += clock.o apic.o i8259.o ioapic.o i8254.o pci-assign.o
> +obj-$(CONFIG_KVM) += clock.o apic.o i8259.o ioapic.o i8254.o pci-assign.o pv_event.o
> diff --git a/hw/kvm/pv_event.c b/hw/kvm/pv_event.c
> new file mode 100644
> index 0000000..5e68190
> --- /dev/null
> +++ b/hw/kvm/pv_event.c
> @@ -0,0 +1,198 @@
> +/*
> + * QEMU KVM support, paravirtual event device
> + *
> + * Copyright Fujitsu, Corp. 2012
> + *
> + * Authors:
> + * Wen Congyang <wency@cn.fujitsu.com>
> + *
> + * This work is licensed under the terms of the GNU GPL, version 2 or later.
> + * See the COPYING file in the top-level directory.
> + *
> + */
> +
> +#include <linux/kvm_para.h>
> +#include <asm/kvm_para.h>
> +#include <qapi/qmp/qobject.h>
> +#include <qapi/qmp/qjson.h>
> +#include <monitor/monitor.h>
> +#include <sysemu/sysemu.h>
> +#include <sysemu/kvm.h>
> +
> +/* Possible values for action parameter. */
> +#define PANICKED_REPORT 1 /* emit QEVENT_GUEST_PANICKED only */
> +#define PANICKED_PAUSE 2 /* emit QEVENT_GUEST_PANICKED and pause VM */
> +#define PANICKED_POWEROFF 3 /* emit QEVENT_GUEST_PANICKED and quit VM */
> +#define PANICKED_RESET 4 /* emit QEVENT_GUEST_PANICKED and reset VM */
> +
> +#define PV_EVENT_DRIVER "kvm_pv_event"
> +#define PV_IOPORT(obj) OBJECT_CHECK(PVIOPortState, (obj), PV_EVENT_DRIVER)
> +
> +struct PVEventAction {
> + char *panicked_action;
> + int panicked_action_value;
> +};
> +
> +#define DEFINE_PV_EVENT_PROPERTIES(_state, _conf) \
> + DEFINE_PROP_STRING("panicked_action", _state, _conf.panicked_action)
> +
> +static void panicked_mon_event(const char *action)
> +{
> + QObject *data;
> +
> + data = qobject_from_jsonf("{ 'action': %s }", action);
> + monitor_protocol_event(QEVENT_GUEST_PANICKED, data);
> + qobject_decref(data);
> +}
> +
> +static void panicked_perform_action(uint32_t panicked_action)
> +{
> + switch (panicked_action) {
> + case PANICKED_REPORT:
> + panicked_mon_event("report");
> + break;
> +
> + case PANICKED_PAUSE:
> + panicked_mon_event("pause");
> + vm_stop(RUN_STATE_GUEST_PANICKED);
> + break;
> +
> + case PANICKED_POWEROFF:
> + panicked_mon_event("poweroff");
> + qemu_system_shutdown_request();
> + break;
> +
> + case PANICKED_RESET:
> + panicked_mon_event("reset");
> + qemu_system_reset_request();
> + break;
> + }
> +}
> +
> +static uint64_t supported_event(void)
> +{
> + return 1 << KVM_PV_FEATURE_PANICKED;
> +}
> +
> +static void handle_event(int event, struct PVEventAction *conf)
> +{
> + if (event == KVM_PV_EVENT_PANICKED) {
> + panicked_perform_action(conf->panicked_action_value);
> + }
> +}
> +
> +static int pv_event_init(struct PVEventAction *conf)
> +{
> + if (!conf->panicked_action) {
> + conf->panicked_action_value = PANICKED_REPORT;
> + } else if (strcasecmp(conf->panicked_action, "none") == 0) {
> + conf->panicked_action_value = PANICKED_REPORT;
> + } else if (strcasecmp(conf->panicked_action, "pause") == 0) {
> + conf->panicked_action_value = PANICKED_PAUSE;
> + } else if (strcasecmp(conf->panicked_action, "poweroff") == 0) {
> + conf->panicked_action_value = PANICKED_POWEROFF;
> + } else if (strcasecmp(conf->panicked_action, "reset") == 0) {
> + conf->panicked_action_value = PANICKED_RESET;
> + } else {
> + return -1;
> + }
> +
> + return 0;
> +}
> +
> +#if defined(KVM_PV_EVENT_PORT)
> +
> +#include "hw/isa.h"
> +
> +typedef struct {
> + ISADevice dev;
> + struct PVEventAction conf;
> + MemoryRegion ioport;
> +} PVIOPortState;
> +
> +static uint64_t pv_io_read(void *opaque, hwaddr addr, unsigned size)
> +{
> + return supported_event();
> +}
> +
> +static void pv_io_write(void *opaque, hwaddr addr, uint64_t val,
> + unsigned size)
> +{
> + PVIOPortState *s = opaque;
> +
> + handle_event(val, &s->conf);
> +}
> +
> +static const MemoryRegionOps pv_io_ops = {
> + .read = pv_io_read,
> + .write = pv_io_write,
> + .impl = {
> + .min_access_size = 4,
> + .max_access_size = 4,
> + },
> +};
> +
> +static int pv_ioport_initfn(ISADevice *dev)
> +{
> + PVIOPortState *s = PV_IOPORT(dev);
> +
> + if (pv_event_init(&s->conf) < 0) {
> + return -1;
> + }
> +
> + memory_region_init_io(&s->ioport, &pv_io_ops, s, "pv_event", 4);
> + isa_register_ioport(dev, &s->ioport, KVM_PV_EVENT_PORT);
> +
> + return 0;
> +}
> +
> +static Property pv_ioport_properties[] = {
> + DEFINE_PV_EVENT_PROPERTIES(PVIOPortState, conf),
> + DEFINE_PROP_END_OF_LIST(),
> +};
> +
> +static void pv_ioport_class_init(ObjectClass *klass, void *data)
> +{
> + DeviceClass *dc = DEVICE_CLASS(klass);
> + ISADeviceClass *ic = ISA_DEVICE_CLASS(klass);
> +
> + ic->init = pv_ioport_initfn;
> + dc->no_user = 1;
> + dc->props = pv_ioport_properties;
> +}
> +
> +static TypeInfo pv_ioport_info = {
> + .name = PV_EVENT_DRIVER,
> + .parent = TYPE_ISA_DEVICE,
> + .instance_size = sizeof(PVIOPortState),
> + .class_init = pv_ioport_class_init,
> +};
> +
> +static void pv_ioport_register_types(void)
> +{
> + type_register_static(&pv_ioport_info);
> +}
> +
> +type_init(pv_ioport_register_types)
> +
> +void kvm_pv_event_init(void *opaque)
> +{
> + ISABus *bus = opaque;
> + ISADevice *dev;
> +
> + dev = isa_create(bus, PV_EVENT_DRIVER);
> + qdev_init_nofail(&dev->qdev);
> +}
> +
> +#else
> +
> +/*
> + * If you need a qom device to handle pv event, this device should
> + * be created and initialized in kvm_pv_event_init().
> + *
> + * The parameter opaque is the device's parent bus.
> + */
> +void kvm_pv_event_init(void *opaque)
> +{
> +}
> +#endif
> diff --git a/hw/pc_piix.c b/hw/pc_piix.c
> index aa9cc81..24a9bf3 100644
> --- a/hw/pc_piix.c
> +++ b/hw/pc_piix.c
> @@ -47,6 +47,7 @@
> #ifdef CONFIG_XEN
> # include <xen/hvm/hvm_info_table.h>
> #endif
> +#include <linux/kvm_para.h>
>
> #define MAX_IDE_BUS 2
>
> @@ -216,6 +217,10 @@ static void pc_init1(MemoryRegion *system_memory,
> if (pci_enabled) {
> pc_pci_device_init(pci_bus);
> }
> +
> + if (kvm_enabled()) {
> + kvm_pv_event_init(isa_bus);
> + }
> }
>
> static void pc_init_pci(QEMUMachineInitArgs *args)
> diff --git a/include/sysemu/kvm.h b/include/sysemu/kvm.h
> index f2d97b5..97d3daf 100644
> --- a/include/sysemu/kvm.h
> +++ b/include/sysemu/kvm.h
> @@ -296,4 +296,6 @@ int kvm_irqchip_add_irqfd_notifier(KVMState *s, EventNotifier *n, int virq);
> int kvm_irqchip_remove_irqfd_notifier(KVMState *s, EventNotifier *n, int virq);
> void kvm_pc_gsi_handler(void *opaque, int n, int level);
> void kvm_pc_setup_irq_routing(bool pci_enabled);
> +
> +void kvm_pv_event_init(void *opaque);
> #endif
> diff --git a/kvm-stub.c b/kvm-stub.c
> index 760aadc..f543fa2 100644
> --- a/kvm-stub.c
> +++ b/kvm-stub.c
> @@ -145,3 +145,7 @@ int kvm_irqchip_remove_irqfd_notifier(KVMState *s, EventNotifier *n, int virq)
> {
> return -ENOSYS;
> }
> +
> +void kvm_pv_event_init(void *opaque)
> +{
> +}
>