Re: [Qemu-devel] [PATCH for-2.4 1/2] core: reset handler for bus-less devices

["Andreas Färber" <afaerber@suse.de>]

Am 13.07.2015 um 16:11 schrieb Cornelia Huck:
> On Mon, 13 Jul 2015 14:22:05 +0200
> Christian Borntraeger <borntraeger@de.ibm.com> wrote:
> 
>> Am 09.07.2015 um 18:51 schrieb Cornelia Huck:
>>> Devices that don't live on a bus aren't caught by the normal device
>>> reset logic. Let's register a reset handler for those devices during
>>> device realization that calls the reset handler for the associated
>>> device class.
>>>
>>> Suggested-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
>>> Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
>> reboot (from within guest) and external reset (system_reset in monitor)
>> now work fine with the s390 watchdog.
>>
>> Tested-by: Christian Borntraeger <borntraeger@de.ibm.com>
>>
>>> ---
>>>  hw/core/qdev.c | 15 +++++++++++++++
>>>  1 file changed, 15 insertions(+)
> 
> Thanks.
> 
> Any objections against taking this through s390-next? I'd like to fix
> diag288 reset (+ that annoying migration regession) for 2.4-rc1 and
> send a pull request soon.

Which device does this fix (only this diag88?), and is it really not
possible to register a reset handler where it's being created?

Peter C.'s theory does not match practice for x86, and this patch will
lead to bus-less devices that are properly being reset by their parent
getting reset twice, potentially causing issues due to qemu_irqs. I'd
rather avoid that.

One workaround would be to amend this patch with a DeviceClass flag for
whether to enable this new behavior, defaulting to no and getting
overridden by your affected device.

Regards,
Andreas

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