qemu/hw/core
Michael Roth 04162f8f4b qdev: store DeviceState's canonical path to use when unparenting
device_unparent(dev, ...) is called when a device is unparented,
either directly, or as a result of a parent device being
finalized, and handles some final cleanup for the device. Part
of this includes emiting a DEVICE_DELETED QMP event to notify
management, which includes the device's path in the composition
tree as provided by object_get_canonical_path().

object_get_canonical_path() assumes the device is still connected
to the machine/root container, and will assert otherwise, but
in some situations this isn't the case:

If the parent is finalized as a result of object_unparent(), it
will still be attached to the composition tree at the time any
children are unparented as a result of that same call to
object_unparent(). However, in some cases, object_unparent()
will complete without finalizing the parent device, due to
lingering references that won't be released till some time later.
One such example is if the parent has MemoryRegion children (which
take a ref on their parent), who in turn have AddressSpace's (which
take a ref on their regions), since those AddressSpaces get cleaned
up asynchronously by the RCU thread.

In this case qdev:device_unparent() may be called for a child Device
that no longer has a path to the root/machine container, causing
object_get_canonical_path() to assert.

Fix this by storing the canonical path during realize() so the
information will still be available for device_unparent() in such
cases.

Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Signed-off-by: Greg Kurz <groug@kaod.org>
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Tested-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Message-Id: <20171016222315.407-2-mdroth@linux.vnet.ibm.com>
[Clear dev->canonical_path at the post_realize_fail label, which is
 cleaner.  Suggested by David Gibson. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-10-18 10:34:17 +02:00
..
bus.c bus: do not unref hotplug handler 2017-03-01 11:51:28 +04:00
empty_slot.c hw/core: Clean up includes 2016-01-29 15:07:25 +00:00
fw-path-provider.c hw/core: Clean up includes 2016-01-29 15:07:25 +00:00
generic-loader.c hw/core/generic-loader: Fix crash when running without CPU 2017-05-10 10:19:23 +03:00
hotplug.c qdev: hotplug: drop HotplugHandler.post_plug callback 2016-11-15 17:20:37 +02:00
irq.c tcg: drop global lock during TCG code execution 2017-02-24 10:32:45 +00:00
loader-fit.c loader: Support Flattened Image Trees (FIT images) 2017-02-21 23:47:40 +00:00
loader.c fw_cfg: rename read callback 2017-09-08 16:15:17 +03:00
machine.c machine: Add a valid_cpu_types property 2017-10-09 23:21:52 -03:00
Makefile.objs hw/core: nmi.c can be compiled as common-obj nowadays 2017-06-05 17:23:36 +03:00
nmi.c nmi: remove x86 specific nmi handling 2016-05-23 16:53:46 +02:00
null-machine.c hw/core/null-machine: Print error message when using the -kernel parameter 2017-04-20 15:22:41 -03:00
or-irq.c qdev: Replace cannot_instantiate_with_device_add_yet with !user_creatable 2017-05-17 10:37:00 -03:00
platform-bus.c platform-bus: use get_uint() for "addr" property 2017-06-20 14:31:32 +02:00
ptimer.c qemu-timer: do not include sysemu/cpus.h from util/qemu-timer.h 2017-03-14 13:28:18 +01:00
qdev-properties-system.c qdev: Add const qualifier to PropertyInfo definitions 2017-07-14 12:04:42 +02:00
qdev-properties.c qapi: Change data type of the FOO_lookup generated for enum FOO 2017-09-04 13:09:13 +02:00
qdev.c qdev: store DeviceState's canonical path to use when unparenting 2017-10-18 10:34:17 +02:00
register.c register: display register prefix (name) since it is available 2017-06-04 18:42:55 +03:00
reset.c hw: move reset handlers from vl.c to hw/core 2017-01-16 17:52:35 +01:00
stream.c hw/core: Clean up includes 2016-01-29 15:07:25 +00:00
sysbus.c sysbus: Set user_creatable=false by default on TYPE_SYS_BUS_DEVICE 2017-05-17 10:37:01 -03:00
uboot_image.h Clean up ill-advised or unusual header guards 2016-07-12 16:20:46 +02:00