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Date: Fri, 22 Feb 2019 16:53:55 +0800
From: Wei Yang <richardw.yang@linux.intel.com>
Message-ID: <20190222085355.GA30665@richard>
Reply-To: Wei Yang <richardw.yang@linux.intel.com>
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	<20190221154551.5ab655f4@redhat.com>
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Subject: Re: [Qemu-devel] [PATCH v4] i386,
 acpi: check acpi_memory_hotplug capacity in pre_plug
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To: Igor Mammedov <imammedo@redhat.com>
Cc: Wei Yang <richardw.yang@linux.intel.com>, qemu-devel@nongnu.org, mst@redhat.com, marcel.apfelbaum@gmail.com, eblake@redhat.com

On Thu, Feb 21, 2019 at 03:45:51PM +0100, Igor Mammedov wrote:
>On Tue, 19 Feb 2019 16:08:26 +0800
>Wei Yang <richardw.yang@linux.intel.com> wrote:
>
>> Currently we do device realization like below:
>> 
>>    hotplug_handler_pre_plug()
>>    dc->realize()
>>    hotplug_handler_plug()
>> 
>> Before we do device realization and plug, we should allocate necessary
>> resources and check if memory-hotplug-support property is enabled.
>> 
>> At the piix4 and ich9, the memory-hotplug-support property is checked at
>> plug stage. This means that device has been realized and mapped into guest
>> address space 'pc_dimm_plug()' by the time acpi plug handler is called,
>> where it might fail and crash QEMU due to reaching g_assert_not_reached()
>> (piix4) or error_abort (ich9).
>> 
>> Fix it by checking if memory hotplug is enabled at pre_plug stage
>> where we can gracefully abort hotplug request.
>> 
>> Signed-off-by: Wei Yang <richardw.yang@linux.intel.com>
>> CC: Igor Mammedov <imammedo@redhat.com>
>> CC: Eric Blake <eblake@redhat.com>
>patch refuses to be applied to current master
>

Could latest upstream compile successfully?

-- 
Wei Yang
Help you, Help me