Re: [Qemu-devel] [PATCH 5/6 v5] deal with guest panicked event accoring to -onpanic parameter

[Jan Kiszka]

On 2012-06-28 03:15, Wen Congyang wrote:
> At 06/27/2012 10:39 PM, Jan Kiszka Wrote:
>> On 2012-06-27 09:02, Wen Congyang wrote:
>>> When the guest is panicked, it will write 0x1 to the port KVM_PV_PORT.
>>> 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 the guest
>>> 3. emit QEVENT_GUEST_PANICKED and poweroff the guest
>>> 4. emit QEVENT_GUEST_PANICKED and reset the guest
>>>
>>> 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.
>>>
>>> Signed-off-by: Wen Congyang <address@hidden>
>>> ---
>>>  kvm-all.c       |  101 
>>> +++++++++++++++++++++++++++++++++++++++++++++++++++++++
>>>  kvm-stub.c      |    9 +++++
>>>  kvm.h           |    3 ++
>>>  qemu-options.hx |   15 ++++++++
>>>  vl.c            |   10 +++++
>>>  5 files changed, 138 insertions(+), 0 deletions(-)
>>>
>>> diff --git a/kvm-all.c b/kvm-all.c
>>> index f8e4328..9494dd2 100644
>>> --- a/kvm-all.c
>>> +++ b/kvm-all.c
>>> @@ -19,6 +19,8 @@
>>>  #include <stdarg.h>
>>>  
>>>  #include <linux/kvm.h>
>>> +#include <linux/kvm_para.h>
>>> +#include <asm/kvm_para.h>
>>>  
>>>  #include "qemu-common.h"
>>>  #include "qemu-barrier.h"
>>> @@ -32,6 +34,9 @@
>>>  #include "bswap.h"
>>>  #include "memory.h"
>>>  #include "exec-memory.h"
>>> +#include "iorange.h"
>>> +#include "qemu-objects.h"
>>> +#include "monitor.h"
>>>  
>>>  /* This check must be after config-host.h is included */
>>>  #ifdef CONFIG_EVENTFD
>>> @@ -1931,3 +1936,99 @@ 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_POWEROFF   3   /* emit QEVENT_GUEST_PANICKED and quit VM 
>>> */
>>> +#define PANICKED_RESET      4   /* emit QEVENT_GUEST_PANICKED and reset 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_POWEROFF:
>>> +        panicked_mon_event("poweroff");
>>> +        exit(0);
>>> +        break;
>>> +    case PANICKED_RESET:
>>> +        panicked_mon_event("reset");
>>> +        qemu_system_reset_request();
>>> +        break;
>>> +    }
>>> +}
>>> +
>>> +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,
>>> +};
>>> +
>>> +#if defined(KVM_PV_PORT)
>>> +void kvm_pv_port_init(void)
>>> +{
>>> +    IORange *pv_io_range = g_malloc(sizeof(IORange));
>>> +
>>> +    iorange_init(pv_io_range, &pv_io_range_ops, KVM_PV_PORT, 1);
>>> +    ioport_register(pv_io_range);
>>
>> This modeling is still not ok. We don't open-code ports anymore, we
>> introduce devices. And this doesn't belong inro generic code as it is
> 
> Do you mean introducing a new device instead of I/O port?

I mean encapsulating the I/O registration (PIO or MMIO) in a QOM device
and building that device only for target archs that supports it. Already
pointed you to examples in hw/kvm/.

Jan

-- 
Siemens AG, Corporate Technology, CT T DE IT 1
Corporate Competence Center Embedded Linux