Re: [Qemu-devel] [PATCH 3/3] deal with guest panicked event

[Wen Congyang <wency@cn.fujitsu.com>]

At 05/31/2012 03:23 AM, Luiz Capitulino Wrote:
> On Mon, 21 May 2012 14:50:51 +0800
> Wen Congyang <wency@cn.fujitsu.com> wrote:
> 
>> When the guest is panicked, it will write 0x1 to the port 0x505. So if
>> qemu reads 0x1 from this port, we can do the folloing three things
>> according to the parameter -onpanic:
>> 1. emit QEVENT_GUEST_PANICKED only
>> 2. emit QEVENT_GUEST_PANICKED and pause VM
>> 3. emit QEVENT_GUEST_PANICKED and quit VM
>>
>> 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.
> 
> It will if it checks the vm status.
> 
> Btw, please, split this further into a patch adding the event, another one
> adding the new runstate and then the rest. One more comment below.

OK, I will split it.

> 
>>
>> Signed-off-by: Wen Congyang <wency@cn.fujitsu.com>
>> ---
>>  kvm-all.c        |   84 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
>>  kvm-stub.c       |    9 ++++++
>>  kvm.h            |    3 ++
>>  monitor.c        |    3 ++
>>  monitor.h        |    1 +
>>  qapi-schema.json |    6 +++-
>>  qemu-options.hx  |   14 +++++++++
>>  qmp.c            |    3 +-
>>  vl.c             |   17 ++++++++++-
>>  9 files changed, 137 insertions(+), 3 deletions(-)
>>
>> diff --git a/kvm-all.c b/kvm-all.c
>> index 9b73ccf..b5b0531 100644
>> --- a/kvm-all.c
>> +++ b/kvm-all.c
>> @@ -19,6 +19,7 @@
>>  #include <stdarg.h>
>>  
>>  #include <linux/kvm.h>
>> +#include <linux/kvm_para.h>
>>  
>>  #include "qemu-common.h"
>>  #include "qemu-barrier.h"
>> @@ -29,6 +30,8 @@
>>  #include "bswap.h"
>>  #include "memory.h"
>>  #include "exec-memory.h"
>> +#include "iorange.h"
>> +#include "qemu-objects.h"
>>  
>>  /* This check must be after config-host.h is included */
>>  #ifdef CONFIG_EVENTFD
>> @@ -1707,3 +1710,84 @@ int kvm_on_sigbus(int code, void *addr)
>>  {
>>      return kvm_arch_on_sigbus(code, addr);
>>  }
>> +
>> +/* 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_QUIT   3   /* emit QEVENT_GUEST_PANICKED and quit VM */
>> +
>> +static int panicked_action = PANICKED_REPORT;
>> +
>> +static void kvm_pv_port_read(IORange *iorange, uint64_t offset, unsigned width,
>> +                             uint64_t *data)
>> +{
>> +    *data = (1 << KVM_PV_FEATURE_PANICKED);
>> +}
>> +
>> +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(void)
>> +{
>> +    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_QUIT:
>> +        panicked_mon_event("quit");
>> +        exit(0);
>> +        break;
>> +    }
> 
> Having the data argument is not needed/wanted. The mngt app can guess it if it
> needs to know it, but I think it doesn't want to.

Libvirt will do something when the kernel is panicked, so it should know the action
in qemu side.

Thanks
Wen Congyang

> 
>> +}
>> +
>> +static void kvm_pv_port_write(IORange *iorange, uint64_t offset, unsigned width,
>> +                              uint64_t data)
>> +{
>> +    if (data == KVM_PV_PANICKED)
>> +        panicked_perform_action();
>> +}
>> +
>> +static void kvm_pv_port_destructor(IORange *iorange)
>> +{
>> +    g_free(iorange);
>> +}
>> +
>> +static IORangeOps pv_io_range_ops = {
>> +    .read = kvm_pv_port_read,
>> +    .write = kvm_pv_port_write,
>> +    .destructor = kvm_pv_port_destructor,
>> +};
>> +
>> +void kvm_pv_port_init(void)
>> +{
>> +    IORange *pv_io_range = g_malloc(sizeof(IORange));
>> +
>> +    iorange_init(pv_io_range, &pv_io_range_ops, 0x505, 1);
>> +    ioport_register(pv_io_range);
>> +}
>> +
>> +int select_panicked_action(const char *p)
>> +{
>> +    if (strcasecmp(p, "report") == 0)
>> +        panicked_action = PANICKED_REPORT;
>> +    else if (strcasecmp(p, "pause") == 0)
>> +        panicked_action = PANICKED_PAUSE;
>> +    else if (strcasecmp(p, "quit") == 0)
>> +        panicked_action = PANICKED_QUIT;
>> +    else
>> +        return -1;
>> +
>> +    return 0;
>> +}
>> diff --git a/kvm-stub.c b/kvm-stub.c
>> index 47c573d..4cf977e 100644
>> --- a/kvm-stub.c
>> +++ b/kvm-stub.c
>> @@ -128,3 +128,12 @@ int kvm_on_sigbus(int code, void *addr)
>>  {
>>      return 1;
>>  }
>> +
>> +void kvm_pv_port_init(void)
>> +{
>> +}
>> +
>> +int select_panicked_action(const char *p)
>> +{
>> +    return -1;
>> +}
>> diff --git a/kvm.h b/kvm.h
>> index 4ccae8c..95075cf 100644
>> --- a/kvm.h
>> +++ b/kvm.h
>> @@ -60,6 +60,9 @@ int kvm_has_gsi_routing(void);
>>  
>>  int kvm_allows_irq0_override(void);
>>  
>> +void kvm_pv_port_init(void);
>> +int select_panicked_action(const char *p);
>> +
>>  #ifdef NEED_CPU_H
>>  int kvm_init_vcpu(CPUArchState *env);
>>  
>> diff --git a/monitor.c b/monitor.c
>> index 12a6fe2..83cb059 100644
>> --- a/monitor.c
>> +++ b/monitor.c
>> @@ -493,6 +493,9 @@ void monitor_protocol_event(MonitorEvent event, QObject *data)
>>          case QEVENT_WAKEUP:
>>              event_name = "WAKEUP";
>>              break;
>> +        case QEVENT_GUEST_PANICKED:
>> +            event_name = "GUEST_PANICKED";
>> +            break;
>>          default:
>>              abort();
>>              break;
>> diff --git a/monitor.h b/monitor.h
>> index 0d49800..94e8a3c 100644
>> --- a/monitor.h
>> +++ b/monitor.h
>> @@ -41,6 +41,7 @@ typedef enum MonitorEvent {
>>      QEVENT_DEVICE_TRAY_MOVED,
>>      QEVENT_SUSPEND,
>>      QEVENT_WAKEUP,
>> +    QEVENT_GUEST_PANICKED,
>>      QEVENT_MAX,
>>  } MonitorEvent;
>>  
>> diff --git a/qapi-schema.json b/qapi-schema.json
>> index 2ca7195..ee5c9e9 100644
>> --- a/qapi-schema.json
>> +++ b/qapi-schema.json
>> @@ -119,11 +119,15 @@
>>  # @suspended: guest is suspended (ACPI S3)
>>  #
>>  # @watchdog: the watchdog action is configured to pause and has been triggered
>> +#
>> +# @guest-panicked: the panicked action is configured to pause and has been
>> +# triggered.
>>  ##
>>  { 'enum': 'RunState',
>>    'data': [ 'debug', 'inmigrate', 'internal-error', 'io-error', 'paused',
>>              'postmigrate', 'prelaunch', 'finish-migrate', 'restore-vm',
>> -            'running', 'save-vm', 'shutdown', 'suspended', 'watchdog' ] }
>> +            'running', 'save-vm', 'shutdown', 'suspended', 'watchdog',
>> +            'guest-panicked' ] }
>>  
>>  ##
>>  # @StatusInfo:
>> diff --git a/qemu-options.hx b/qemu-options.hx
>> index 8b66264..d3d21a1 100644
>> --- a/qemu-options.hx
>> +++ b/qemu-options.hx
>> @@ -2743,6 +2743,20 @@ DEF("qtest-log", HAS_ARG, QEMU_OPTION_qtest_log,
>>      "-qtest-log LOG  specify tracing options\n",
>>      QEMU_ARCH_ALL)
>>  
>> +DEF("onpanic", HAS_ARG, QEMU_OPTION_onpanic, \
>> +    "-onpanic report|pause|quit\n" \
>> +    "                action when the guest is panicked [default=report]",
>> +    QEMU_ARCH_ALL)
>> +STEXI
>> +@item -onpanic @var{action}
>> +
>> +The @var{action} controls what QEmu will do when the guest is panicked.
>> +The default is @code{report} (emit QEVENT_GUEST_PANICKED only).
>> +Other possible actions are:
>> +@code{pause} (emit QEVENT_GUEST_PANICKED and pause VM),
>> +@code{quit} (emit QEVENT_GUEST_PANICKED and quit VM).
>> +ETEXI
>> +
>>  HXCOMM This is the last statement. Insert new options before this line!
>>  STEXI
>>  @end table
>> diff --git a/qmp.c b/qmp.c
>> index fee9fb2..a2d5ce9 100644
>> --- a/qmp.c
>> +++ b/qmp.c
>> @@ -148,7 +148,8 @@ void qmp_cont(Error **errp)
>>          error_set(errp, QERR_MIGRATION_EXPECTED);
>>          return;
>>      } else if (runstate_check(RUN_STATE_INTERNAL_ERROR) ||
>> -               runstate_check(RUN_STATE_SHUTDOWN)) {
>> +               runstate_check(RUN_STATE_SHUTDOWN) ||
>> +               runstate_check(RUN_STATE_GUEST_PANICKED)) {
>>          error_set(errp, QERR_RESET_REQUIRED);
>>          return;
>>      } else if (runstate_check(RUN_STATE_SUSPENDED)) {
>> diff --git a/vl.c b/vl.c
>> index 7f5fed8..8848506 100644
>> --- a/vl.c
>> +++ b/vl.c
>> @@ -367,6 +367,7 @@ static const RunStateTransition runstate_transitions_def[] = {
>>      { RUN_STATE_RUNNING, RUN_STATE_SAVE_VM },
>>      { RUN_STATE_RUNNING, RUN_STATE_SHUTDOWN },
>>      { RUN_STATE_RUNNING, RUN_STATE_WATCHDOG },
>> +    { RUN_STATE_RUNNING, RUN_STATE_GUEST_PANICKED },
>>  
>>      { RUN_STATE_SAVE_VM, RUN_STATE_RUNNING },
>>  
>> @@ -381,6 +382,9 @@ static const RunStateTransition runstate_transitions_def[] = {
>>      { RUN_STATE_WATCHDOG, RUN_STATE_RUNNING },
>>      { RUN_STATE_WATCHDOG, RUN_STATE_FINISH_MIGRATE },
>>  
>> +    { RUN_STATE_GUEST_PANICKED, RUN_STATE_PAUSED },
>> +    { RUN_STATE_GUEST_PANICKED, RUN_STATE_FINISH_MIGRATE },
>> +
>>      { RUN_STATE_MAX, RUN_STATE_MAX },
>>  };
>>  
>> @@ -1537,7 +1541,8 @@ static bool main_loop_should_exit(void)
>>          qemu_system_reset(VMRESET_REPORT);
>>          resume_all_vcpus();
>>          if (runstate_check(RUN_STATE_INTERNAL_ERROR) ||
>> -            runstate_check(RUN_STATE_SHUTDOWN)) {
>> +            runstate_check(RUN_STATE_SHUTDOWN) ||
>> +            runstate_check(RUN_STATE_GUEST_PANICKED)) {
>>              runstate_set(RUN_STATE_PAUSED);
>>              vm_start();
>>          }
>> @@ -3202,6 +3207,12 @@ int main(int argc, char **argv, char **envp)
>>              case QEMU_OPTION_qtest_log:
>>                  qtest_log = optarg;
>>                  break;
>> +            case QEMU_OPTION_onpanic:
>> +                if (select_panicked_action(optarg) == -1) {
>> +                    fprintf(stderr, "Unknown -onpanic parameter\n");
>> +                    exit(1);
>> +                }
>> +                break;
>>              default:
>>                  os_parse_cmd_args(popt->index, optarg);
>>              }
>> @@ -3634,6 +3645,10 @@ int main(int argc, char **argv, char **envp)
>>          }
>>      }
>>  
>> +    if (kvm_enabled()) {
>> +        kvm_pv_port_init();
>> +    }
>> +
>>      if (incoming) {
>>          Error *errp = NULL;
>>          int ret = qemu_start_incoming_migration(incoming, &errp);
> 
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