On Mon, Feb 18, 2019 at 10:50:34AM +0100, Igor Mammedov wrote:
>On Mon, 18 Feb 2019 09:13:33 +0800
>Wei Yang <richardw.y...@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 acpi_memory_hotplug property is checked in
> ^^^^^^^ is field name and not a property so
>s/acpi_memory_hotplug/memory-hotplug-support/
>s/in/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).
>
>
>> This patch abstract the check on acpi_memory_hotplug capacity in
>> pre_plug stage.
>maybe better would be:
>"Fix it by checking if memory hotplug is enabled at pre_plug stage
>where we can gracefully abort hotplug request."
>
>> [changelog rephrase from imamm...@redhat.com]
>this provides zero information for a commit reader,
>it should go under --- to chagelog
>
Ok, maybe different community has different convention.
Linux kernel mm subsystem maintainer suggest me to add above line.
>> Signed-off-by: Wei Yang <richardw.y...@linux.intel.com>
>> CC: Igor Mammedov <imamm...@redhat.com>
>> CC: Eric Blake <ebl...@redhat.com>
>>
>> ---
>> v2:
>> * rephrase change log
>one usually adds commenter's name here
> * like this (some...@foo.bar)
>or
> * (some...@foo.bar)
> - entry 1
> - entry 2
> * (someone-e...@foo.bar)
> - ...
>
Well, I would change to this style.
>> * apply this change to ich9
>> * use hotplug_handler_pre_plug() instead of open-coding check
>> ---
>> hw/acpi/ich9.c | 14 ++++++++++++--
>> hw/acpi/piix4.c | 14 ++++++++++++--
>> hw/i386/pc.c | 5 +++++
>> hw/isa/lpc_ich9.c | 1 +
>> include/hw/acpi/ich9.h | 2 ++
>> 5 files changed, 32 insertions(+), 4 deletions(-)
>>
>> diff --git a/hw/acpi/ich9.c b/hw/acpi/ich9.c
>> index c5d8646abc..906a10f09a 100644
>> --- a/hw/acpi/ich9.c
>> +++ b/hw/acpi/ich9.c
>> @@ -483,13 +483,23 @@ void ich9_pm_add_properties(Object *obj, ICH9LPCPMRegs
>> *pm, Error **errp)
>> NULL);
>> }
>>
>> +void ich9_pm_device_pre_plug_cb(HotplugHandler *hotplug_dev, DeviceState
>> *dev,
>> + Error **errp)
>broken alignment?
>
>run /scripts/checkpatch.pl on patches before submitting them
I copied this from ich9_pm_device_plug_cb(), so thought this is the
correct style.
Will adjust this according to checkpatch.pl.
>
>> +{
>> + ICH9LPCState *lpc = ICH9_LPC_DEVICE(hotplug_dev);
>> +
>> + if (object_dynamic_cast(OBJECT(dev), TYPE_PC_DIMM) &&
>> + !lpc->pm.acpi_memory_hotplug.is_enabled)
>> + error_setg(errp,
>> + "memory hotplug is not enabled: ICH9 memory hotplug disabled");
>I'd give a hint where it's disabled, something like
>
>"memory hotplug is not enabled: %s.memory-hotplug-support is not set",
>object_get_typename(lpc)
>
>the same for piix4
>
>> +}
>> +
>> void ich9_pm_device_plug_cb(HotplugHandler *hotplug_dev, DeviceState *dev,
>> Error **errp)
>> {
>> ICH9LPCState *lpc = ICH9_LPC_DEVICE(hotplug_dev);
>>
>> - if (lpc->pm.acpi_memory_hotplug.is_enabled &&
>> - object_dynamic_cast(OBJECT(dev), TYPE_PC_DIMM)) {
>> + if (object_dynamic_cast(OBJECT(dev), TYPE_PC_DIMM)) {
>> if (object_dynamic_cast(OBJECT(dev), TYPE_NVDIMM)) {
>> nvdimm_acpi_plug_cb(hotplug_dev, dev);
>> } else {
>> diff --git a/hw/acpi/piix4.c b/hw/acpi/piix4.c
>> index e330f24c71..c97b747496 100644
>> --- a/hw/acpi/piix4.c
>> +++ b/hw/acpi/piix4.c
>> @@ -370,13 +370,22 @@ static void piix4_pm_powerdown_req(Notifier *n, void
>> *opaque)
>> acpi_pm1_evt_power_down(&s->ar);
>> }
>>
>> +static void piix4_device_pre_plug_cb(HotplugHandler *hotplug_dev,
>> + DeviceState *dev, Error **errp)
>> +{
>> + PIIX4PMState *s = PIIX4_PM(hotplug_dev);
>> +
>> + if (object_dynamic_cast(OBJECT(dev), TYPE_PC_DIMM) &&
>> + !s->acpi_memory_hotplug.is_enabled)
>> + error_setg(errp,
>> + "memory hotplug is not enabled: PIIX4 memory hotplug disabled");
>> +}
>> static void piix4_device_plug_cb(HotplugHandler *hotplug_dev,
>> DeviceState *dev, Error **errp)
>> {
>> PIIX4PMState *s = PIIX4_PM(hotplug_dev);
>>
>> - if (s->acpi_memory_hotplug.is_enabled &&
>> - object_dynamic_cast(OBJECT(dev), TYPE_PC_DIMM)) {
>> + if (object_dynamic_cast(OBJECT(dev), TYPE_PC_DIMM)) {
>> if (object_dynamic_cast(OBJECT(dev), TYPE_NVDIMM)) {
>> nvdimm_acpi_plug_cb(hotplug_dev, dev);
>> } else {
>> @@ -702,6 +711,7 @@ static void piix4_pm_class_init(ObjectClass *klass, void
>> *data)
>> */
>> dc->user_creatable = false;
>> dc->hotpluggable = false;
>> + hc->pre_plug = piix4_device_pre_plug_cb;
>> hc->plug = piix4_device_plug_cb;
>> hc->unplug_request = piix4_device_unplug_request_cb;
>> hc->unplug = piix4_device_unplug_cb;
>> diff --git a/hw/i386/pc.c b/hw/i386/pc.c
>> index 734d3268fa..59c8ccf0ff 100644
>> --- a/hw/i386/pc.c
>> +++ b/hw/i386/pc.c
>> @@ -1674,6 +1674,11 @@ static void pc_memory_pre_plug(HotplugHandler
>> *hotplug_dev, DeviceState *dev,
>> return;
>> }
>>
>> + /*
>> + * Check acpi_dev memory-hotplug-support property
>> + */
>> + hotplug_handler_pre_plug(pcms->acpi_dev, dev, errp);
>> +
>> if (is_nvdimm && !pcms->acpi_nvdimm_state.is_enabled) {
>> error_setg(errp, "nvdimm is not enabled: missing 'nvdimm' in '-M'");
>> return;
>> diff --git a/hw/isa/lpc_ich9.c b/hw/isa/lpc_ich9.c
>> index e692b9fdc1..ac44aa53be 100644
>> --- a/hw/isa/lpc_ich9.c
>> +++ b/hw/isa/lpc_ich9.c
>> @@ -805,6 +805,7 @@ static void ich9_lpc_class_init(ObjectClass *klass, void
>> *data)
>> * pc_q35_init()
>> */
>> dc->user_creatable = false;
>> + hc->pre_plug = ich9_pm_device_pre_plug_cb;
>> hc->plug = ich9_pm_device_plug_cb;
>> hc->unplug_request = ich9_pm_device_unplug_request_cb;
>> hc->unplug = ich9_pm_device_unplug_cb;
>> diff --git a/include/hw/acpi/ich9.h b/include/hw/acpi/ich9.h
>> index 59aeb06393..428af0b0be 100644
>> --- a/include/hw/acpi/ich9.h
>> +++ b/include/hw/acpi/ich9.h
>> @@ -74,6 +74,8 @@ extern const VMStateDescription vmstate_ich9_pm;
>>
>> void ich9_pm_add_properties(Object *obj, ICH9LPCPMRegs *pm, Error **errp);
>>
>> +void ich9_pm_device_pre_plug_cb(HotplugHandler *hotplug_dev, DeviceState
>> *dev,
>> + Error **errp);
>> void ich9_pm_device_plug_cb(HotplugHandler *hotplug_dev, DeviceState *dev,
>> Error **errp);
>> void ich9_pm_device_unplug_request_cb(HotplugHandler *hotplug_dev,
>
--
Wei Yang
Help you, Help me
