Re: [Qemu-devel] [PATCH v7] i386, acpi: check acpi_memory_hotplug capacity in pre_plug

2019-03-06 Thread Igor Mammedov 
On Fri,  1 Mar 2019 11:35:48 +0800
Wei Yang  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 
> CC: Igor Mammedov 
> CC: Eric Blake 
> Signed-off-by: Wei Yang 

Reviewed-by: Igor Mammedov 

> 
> ---
> v7:
>* fix code style
> v6:
>* fix the check in piix4_device_pre_plug_cb
> v5:
>* rebase on latest upstream
>* remove a comment before hotplug_handler_pre_plug
>* fix alignment for ich9_pm_device_pre_plug_cb
> v4:
>* fix code alignment of piix4_device_pre_plug_cb
> v3:
>* replace acpi_memory_hotplug with memory-hotplug-support in changelog
>* fix code alignment of ich9_pm_device_pre_plug_cb
>* print which device type memory-hotplug-support is disabled in
>  ich9_pm_device_pre_plug_cb and piix4_device_pre_plug_cb
> v2:
>* (imamm...@redhat.com)
>  - Almost the whole third paragraph
>* apply this change to ich9
>* use hotplug_handler_pre_plug() instead of open-coding check
> ---
>  hw/acpi/ich9.c | 15 +--
>  hw/acpi/piix4.c| 13 ++---
>  hw/i386/pc.c   |  2 ++
>  hw/isa/lpc_ich9.c  |  1 +
>  include/hw/acpi/ich9.h |  2 ++
>  5 files changed, 28 insertions(+), 5 deletions(-)
> 
> diff --git a/hw/acpi/ich9.c b/hw/acpi/ich9.c
> index c5d8646abc..e53dfe1ee3 100644
> --- a/hw/acpi/ich9.c
> +++ b/hw/acpi/ich9.c
> @@ -483,13 +483,24 @@ 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)
> +{
> +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: %s.memory-hotplug-support 
> "
> +   "is not set", object_get_typename(OBJECT(lpc)));
> +}
> +
>  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 df8c0db909..c5a4b3f9fe 100644
> --- a/hw/acpi/piix4.c
> +++ b/hw/acpi/piix4.c
> @@ -374,9 +374,17 @@ static void piix4_pm_powerdown_req(Notifier *n, void 
> *opaque)
>  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_PCI_DEVICE)) {
>  acpi_pcihp_device_pre_plug_cb(hotplug_dev, dev, errp);
> -} else if (!object_dynamic_cast(OBJECT(dev), TYPE_PC_DIMM) &&
> +} else if (object_dynamic_cast(OBJECT(dev), TYPE_PC_DIMM)) {
> +if (!s->acpi_memory_hotplug.is_enabled) {
> +error_setg(errp,
> +"memory hotplug is not enabled: %s.memory-hotplug-support "
> +"is not set", object_get_typename(OBJECT(s)));
> +}
> +} else if (
> !object_dynamic_cast(OBJECT(dev), TYPE_CPU)) {
>  error_setg(errp, "acpi: device pre plug request for not supported"
> " device type: %s", object_get_typename(OBJECT(dev)));
> @@ -388,8 +396,7 @@ static void piix4_device_plug_cb(HotplugHandler 
> *hotplug_dev,
>  {
>  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 {
> diff --git a/hw/i386/pc.c b/hw/i386/pc.c
> index 578f772e7c..64d9e756fa 100644
> --- a/hw/i386/pc.c
> +++ b/hw/i386/pc.c
> @@ -2083,6 +2083,8 @@ static void

[Qemu-devel] [PATCH v7] i386, acpi: check acpi_memory_hotplug capacity in pre_plug

2019-02-28 Thread Wei Yang 
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 
CC: Igor Mammedov 
CC: Eric Blake 
Signed-off-by: Wei Yang 

---
v7:
   * fix code style
v6:
   * fix the check in piix4_device_pre_plug_cb
v5:
   * rebase on latest upstream
   * remove a comment before hotplug_handler_pre_plug
   * fix alignment for ich9_pm_device_pre_plug_cb
v4:
   * fix code alignment of piix4_device_pre_plug_cb
v3:
   * replace acpi_memory_hotplug with memory-hotplug-support in changelog
   * fix code alignment of ich9_pm_device_pre_plug_cb
   * print which device type memory-hotplug-support is disabled in
 ich9_pm_device_pre_plug_cb and piix4_device_pre_plug_cb
v2:
   * (imamm...@redhat.com)
 - Almost the whole third paragraph
   * apply this change to ich9
   * use hotplug_handler_pre_plug() instead of open-coding check
---
 hw/acpi/ich9.c | 15 +--
 hw/acpi/piix4.c| 13 ++---
 hw/i386/pc.c   |  2 ++
 hw/isa/lpc_ich9.c  |  1 +
 include/hw/acpi/ich9.h |  2 ++
 5 files changed, 28 insertions(+), 5 deletions(-)

diff --git a/hw/acpi/ich9.c b/hw/acpi/ich9.c
index c5d8646abc..e53dfe1ee3 100644
--- a/hw/acpi/ich9.c
+++ b/hw/acpi/ich9.c
@@ -483,13 +483,24 @@ 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)
+{
+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: %s.memory-hotplug-support "
+   "is not set", object_get_typename(OBJECT(lpc)));
+}
+
 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 df8c0db909..c5a4b3f9fe 100644
--- a/hw/acpi/piix4.c
+++ b/hw/acpi/piix4.c
@@ -374,9 +374,17 @@ static void piix4_pm_powerdown_req(Notifier *n, void 
*opaque)
 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_PCI_DEVICE)) {
 acpi_pcihp_device_pre_plug_cb(hotplug_dev, dev, errp);
-} else if (!object_dynamic_cast(OBJECT(dev), TYPE_PC_DIMM) &&
+} else if (object_dynamic_cast(OBJECT(dev), TYPE_PC_DIMM)) {
+if (!s->acpi_memory_hotplug.is_enabled) {
+error_setg(errp,
+"memory hotplug is not enabled: %s.memory-hotplug-support "
+"is not set", object_get_typename(OBJECT(s)));
+}
+} else if (
!object_dynamic_cast(OBJECT(dev), TYPE_CPU)) {
 error_setg(errp, "acpi: device pre plug request for not supported"
" device type: %s", object_get_typename(OBJECT(dev)));
@@ -388,8 +396,7 @@ static void piix4_device_plug_cb(HotplugHandler 
*hotplug_dev,
 {
 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 {
diff --git a/hw/i386/pc.c b/hw/i386/pc.c
index 578f772e7c..64d9e756fa 100644
--- a/hw/i386/pc.c
+++ b/hw/i386/pc.c
@@ -2083,6 +2083,8 @@ static void pc_memory_pre_plug(HotplugHandler 
*hotplug_dev, DeviceState *dev,
 return;
 }
 
+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