On Thu, Sep 22, 2016 at 1:08 AM, John Snow <js...@redhat.com> wrote:
>
>
> On 09/21/2016 01:53 PM, Ashijeet Acharya wrote:
>>
>> Fix a memory leak in ide_register_restart_cb() in hw/ide/core.c and add
>> idebus_unrealize() in hw/ide/qdev.c to have calls to
>> qemu_del_vm_change_state_handler() to deal with the dangling change
>> state handler during hot-unplugging ide devices which might lead to a
>> crash.
>>
>
> Minor rebase issue, but it's trivially resolved.
>
>
>> Signed-off-by: Ashijeet Acharya <ashijeetacha...@gmail.com>
>> ---
>> Changes in v2:
>> -v1 was corrupted at line 64
>> -Move idebus_unrealize() below ide_bus_class_init()
>> ---
>> hw/ide/core.c | 2 +-
>> hw/ide/qdev.c | 13 +++++++++++++
>> include/hw/ide/internal.h | 1 +
>> 3 files changed, 15 insertions(+), 1 deletion(-)
>>
>> diff --git a/hw/ide/core.c b/hw/ide/core.c
>> index 45b6df1..eecbb47 100644
>> --- a/hw/ide/core.c
>> +++ b/hw/ide/core.c
>> @@ -2582,7 +2582,7 @@ static void ide_restart_cb(void *opaque, int
>> running, RunState state)
>> void ide_register_restart_cb(IDEBus *bus)
>> {
>> if (bus->dma->ops->restart_dma) {
>> - qemu_add_vm_change_state_handler(ide_restart_cb, bus);
>> + bus->vmstate = qemu_add_vm_change_state_handler(ide_restart_cb,
>> bus);
>> }
>> }
>>
>> diff --git a/hw/ide/qdev.c b/hw/ide/qdev.c
>> index 2eb055a..c94f9f8 100644
>> --- a/hw/ide/qdev.c
>> +++ b/hw/ide/qdev.c
>> @@ -31,6 +31,7 @@
>> /* --------------------------------- */
>>
>> static char *idebus_get_fw_dev_path(DeviceState *dev);
>> +static void idebus_unrealize(DeviceState *qdev, Error **errp);
>>
>> static Property ide_props[] = {
>> DEFINE_PROP_UINT32("unit", IDEDevice, unit, -1),
>> @@ -44,6 +45,17 @@ static void ide_bus_class_init(ObjectClass *klass, void
>> *data)
>> k->get_fw_dev_path = idebus_get_fw_dev_path;
>> }
>>
>> +static void idebus_unrealize(DeviceState *qdev, Error **errp)
>> +{
>> + IDEBus *bus = DO_UPCAST(IDEBus, qbus, qdev->parent_bus);
>> +
>> + if (bus->dma->ops->restart_dma) {
>> + if (bus->vmstate) {
>> + qemu_del_vm_change_state_handler(bus->vmstate);
>> + }
>> + }
>> +}
>> +
>
>
> Naive question: I saw Paolo say that this should be conditional on
> bus->dma->ops->restart_dma -- Why can't we just say if (bus->vmstate) ?
>
> I see that we only allocate the change state handler when restart_dma is
> present, but this makes this portion of the code look funny when if
> (bus->vmstate) would be just as simple, no?
>
I had a similar thought, because other pieces of code also do it in
"if (bus->vmstate)" manner but maybe I was missing on something
important and ended up coding how Paolo instructed me.
> (Unless we can't rely on its NULL initialization or some such.)
Maybe, but shouldn't the same logic apply elsewhere then?
>
>> static const TypeInfo ide_bus_info = {
>> .name = TYPE_IDE_BUS,
>> .parent = TYPE_BUS,
>> @@ -355,6 +367,7 @@ static void ide_device_class_init(ObjectClass *klass,
>> void *data)
>> k->init = ide_qdev_init;
>> set_bit(DEVICE_CATEGORY_STORAGE, k->categories);
>> k->bus_type = TYPE_IDE_BUS;
>> + k->unrealize = idebus_unrealize;
>> k->props = ide_props;
>> }
>>
>> diff --git a/include/hw/ide/internal.h b/include/hw/ide/internal.h
>> index 7824bc3..2103261 100644
>> --- a/include/hw/ide/internal.h
>> +++ b/include/hw/ide/internal.h
>> @@ -480,6 +480,7 @@ struct IDEBus {
>> uint8_t retry_unit;
>> int64_t retry_sector_num;
>> uint32_t retry_nsector;
>> + VMChangeStateEntry *vmstate;
>
>
> Hmm, I was going to complain and say that 'vmstate' is a generic name for
> this field, but it's by far the most common name for this task. I cede!
>
>> };
>>
>> #define TYPE_IDE_DEVICE "ide-device"
>>
>
> Seems good otherwise, thank you!
Thanks!
Ashijeet
