s390x/cpu: expose the guest crash information

This patch is the s390 implementation of guest crash information,
similar to commit d187e08dc4 ("i386/cpu: add crash-information QOM
property") and the related commits. We will detect several crash
reasons, with the "disabled wait" being the most important one, since
this is used by all s390 guests as a "panic like" notification.

Demonstrate these ways with examples as follows.

  1. crash-information QOM property;

  Run qemu with -qmp unix:qmp-sock,server, then use utility "qmp-shell"
  to execute "qom-get" command, and might get the result like,

  (QEMU) (QEMU) qom-get path=/machine/unattached/device[0] \
      property=crash-information
  {"return": {"core": 0, "reason": "disabled-wait", "psw-mask": 562956395872256, \
      "type": "s390", "psw-addr": 1102832}}

  2. GUEST_PANICKED event reporting;

  Run qemu with a socket option, and telnet or nc to that,
  -chardev socket,id=qmp,port=4444,host=localhost,server \
  -mon chardev=qmp,mode=control,pretty=on \
  Negotiating the mode by { "execute": "qmp_capabilities" }, and the crash
  information will be reported on a guest crash event like,

  {
    "timestamp": {
        "seconds": 1518004739,
        "microseconds": 552563
    },
    "event": "GUEST_PANICKED",
    "data": {
        "action": "pause",
        "info": {
            "core": 0,
            "psw-addr": 1102832,
            "reason": "disabled-wait",
            "psw-mask": 562956395872256,
            "type": "s390"
        }
    }
  }

  3. log;

  Run qemu with the parameters: -D <logfile> -d guest_errors, to
  specify the logfile and log item. The results might be,

  Guest crashed on cpu 0: disabled-wait
  PSW: 0x0002000180000000 0x000000000010d3f0

Co-authored-by: Jing Liu <liujbjl@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Message-Id: <20180209122543.25755-1-borntraeger@de.ibm.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
[CH: tweaked qapi comment]
Signed-off-by: Cornelia Huck <cohuck@redhat.com>

1 files changed, 53 insertions, 2 deletions

diff --git a/qapi/run-state.json b/qapi/run-state.json
index bca46a8..92d29fd 100644
--- a/qapi/run-state.json
+++ b/qapi/run-state.json
@@ -320,22 +320,29 @@
 #
 # An enumeration of the guest panic information types
 #
+# @hyper-v: hyper-v guest panic information type
+#
+# @s390: s390 guest panic information type (Since: 2.12)
+#
 # Since: 2.9
 ##
 { 'enum': 'GuestPanicInformationType',
-  'data': [ 'hyper-v'] }
+  'data': [ 'hyper-v', 's390' ] }
 
 ##
 # @GuestPanicInformation:
 #
 # Information about a guest panic
 #
+# @type: Crash type that defines the hypervisor specific information
+#
 # Since: 2.9
 ##
 {'union': 'GuestPanicInformation',
  'base': {'type': 'GuestPanicInformationType'},
  'discriminator': 'type',
- 'data': { 'hyper-v': 'GuestPanicInformationHyperV' } }
+ 'data': { 'hyper-v': 'GuestPanicInformationHyperV',
+           's390': 'GuestPanicInformationS390' } }
 
 ##
 # @GuestPanicInformationHyperV:
@@ -350,3 +357,47 @@
            'arg3': 'uint64',
            'arg4': 'uint64',
            'arg5': 'uint64' } }
+
+##
+# @S390CrashReason:
+#
+# Reason why the CPU is in a crashed state.
+#
+# @unknown: no crash reason was set
+#
+# @disabled-wait: the CPU has entered a disabled wait state
+#
+# @extint-loop: clock comparator or cpu timer interrupt with new PSW enabled
+#              for external interrupts
+#
+# @pgmint-loop: program interrupt with BAD new PSW
+#
+# @opint-loop: operation exception interrupt with invalid code at the program
+#             interrupt new PSW
+#
+# Since: 2.12
+##
+{ 'enum': 'S390CrashReason',
+  'data': [ 'unknown',
+            'disabled-wait',
+            'extint-loop',
+            'pgmint-loop',
+            'opint-loop' ] }
+
+##
+# @GuestPanicInformationS390:
+#
+# S390 specific guest panic information (PSW)
+#
+# @core: core id of the CPU that crashed
+# @psw-mask: control fields of guest PSW
+# @psw-addr: guest instruction address
+# @reason: guest crash reason
+#
+# Since: 2.12
+##
+{'struct': 'GuestPanicInformationS390',
+ 'data': { 'core': 'uint32',
+           'psw-mask': 'uint64',
+           'psw-addr': 'uint64',
+           'reason': 'S390CrashReason' } }