Re: [Qemu-devel] [PATCH v3] pci: call object_unparent() before free_qdev()

["Michael S. Tsirkin" <mst@redhat.com>]

On Sun, May 20, 2012 at 05:57:45PM +0800, Amos Kong wrote:
> Start VM with 8 multiple-function block devs, hot-removing
> those block devs by 'device_del ...' would cause qemu abort.
> 
> | (qemu) device_del virti0-0-0
> | (qemu) **
> |ERROR:qom/object.c:389:object_delete: assertion failed: (obj->ref == 0)
> 
> It's a regression introduced by commit 57c9fafe
> 
> The whole PCI slot should be removed once. Currently only one func
> is cleaned in pci_unplug_device(), if you try to remove a single
> func by monitor cmd.
> 
> free_qdev() are called for all functions in slot,
> but unparent_delete() is only called for one
> function.
> 
> ---
> aliguori has a better resolution, better to do it in 1.2
> 
> v2: fix warning: too many arguments for format
> v3: move object_unparent() to acpi_piix_eject_slot()
> 
> Signed-off-by: Amos Kong <kongjianjun@gmail.com>

commit is mangled up a bit.  It should be:

subject: xxxx

commit log

Signed-off-by: XXXX

--- 

Versioning info

diff


No need to repost just we that. But we also need to update other pci
hotplug users: hw//shpc.c hw//pcie.c
Not sure about pci-hotplug.c (calls qdev_free on error
handling) - add a virtio blk function with wrong drive
parameter using pci_add and see. Anything else?

> ---
>  hw/acpi_piix4.c |    1 +
>  hw/pci.c        |    1 -
>  2 files changed, 1 insertions(+), 1 deletions(-)
> 
> diff --git a/hw/acpi_piix4.c b/hw/acpi_piix4.c
> index 585da4e..0345490 100644
> --- a/hw/acpi_piix4.c
> +++ b/hw/acpi_piix4.c
> @@ -299,6 +299,7 @@ static void acpi_piix_eject_slot(PIIX4PMState *s, unsigned slots)
>              if (pc->no_hotplug) {
>                  slot_free = false;
>              } else {
> +                object_unparent(OBJECT(dev));
>                  qdev_free(qdev);
>              }
>          }
> diff --git a/hw/pci.c b/hw/pci.c
> index b706e69..c1ebdde 100644
> --- a/hw/pci.c
> +++ b/hw/pci.c
> @@ -1527,7 +1527,6 @@ static int pci_unplug_device(DeviceState *qdev)
>          qerror_report(QERR_DEVICE_NO_HOTPLUG, object_get_typename(OBJECT(dev)));
>          return -1;
>      }
> -    object_unparent(OBJECT(dev));
>      return dev->bus->hotplug(dev->bus->hotplug_qdev, dev,
>                               PCI_HOTPLUG_DISABLED);
>  }
> -- 
> 1.7.1