* [PATCH] spapr: Don't allow unplug of NVLink2 devices
@ 2020-03-31 3:27 David Gibson
2020-03-31 5:11 ` Alexey Kardashevskiy
2020-03-31 7:56 ` Philippe Mathieu-Daudé
0 siblings, 2 replies; 4+ messages in thread
From: David Gibson @ 2020-03-31 3:27 UTC (permalink / raw)
To: aik, groug; +Cc: David Gibson, qemu-ppc, clg, qemu-devel
Currently, we can't properly handle unplug of NVLink2 devices, because we
don't have code to tear down their special memory resources. There's not
a lot of impetus to implement that: since hardware NVLink2 devices can't
be hot unplugged, the guest side drivers don't usually support unplug
anyway.
Therefore, simply prevent unplug of NVLink2 devices.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
---
hw/ppc/spapr_pci.c | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/hw/ppc/spapr_pci.c b/hw/ppc/spapr_pci.c
index 55ca9dee1e..61b84a392d 100644
--- a/hw/ppc/spapr_pci.c
+++ b/hw/ppc/spapr_pci.c
@@ -1665,6 +1665,10 @@ static void spapr_pci_unplug_request(HotplugHandler *plug_handler,
error_setg(errp, "PCI: Hot unplug of PCI bridges not supported");
return;
}
+ if (object_property_get_uint(OBJECT(pdev), "nvlink2-tgt", NULL)) {
+ error_setg(errp, "PCI: Cannot unplug NVLink2 devices");
+ return;
+ }
/* ensure any other present functions are pending unplug */
if (PCI_FUNC(pdev->devfn) == 0) {
--
2.25.1
^ permalink raw reply related [flat|nested] 4+ messages in thread* Re: [PATCH] spapr: Don't allow unplug of NVLink2 devices
2020-03-31 3:27 [PATCH] spapr: Don't allow unplug of NVLink2 devices David Gibson
@ 2020-03-31 5:11 ` Alexey Kardashevskiy
2020-03-31 7:56 ` Philippe Mathieu-Daudé
1 sibling, 0 replies; 4+ messages in thread
From: Alexey Kardashevskiy @ 2020-03-31 5:11 UTC (permalink / raw)
To: David Gibson, groug; +Cc: qemu-ppc, clg, qemu-devel
On 31/03/2020 14:27, David Gibson wrote:
> Currently, we can't properly handle unplug of NVLink2 devices, because we
> don't have code to tear down their special memory resources. There's not
> a lot of impetus to implement that: since hardware NVLink2 devices can't
> be hot unplugged, the guest side drivers don't usually support unplug
> anyway.
>
> Therefore, simply prevent unplug of NVLink2 devices.
>
> Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru>
> ---
> hw/ppc/spapr_pci.c | 4 ++++
> 1 file changed, 4 insertions(+)
>
> diff --git a/hw/ppc/spapr_pci.c b/hw/ppc/spapr_pci.c
> index 55ca9dee1e..61b84a392d 100644
> --- a/hw/ppc/spapr_pci.c
> +++ b/hw/ppc/spapr_pci.c
> @@ -1665,6 +1665,10 @@ static void spapr_pci_unplug_request(HotplugHandler *plug_handler,
> error_setg(errp, "PCI: Hot unplug of PCI bridges not supported");
> return;
> }
> + if (object_property_get_uint(OBJECT(pdev), "nvlink2-tgt", NULL)) {
> + error_setg(errp, "PCI: Cannot unplug NVLink2 devices");
> + return;
> + }
>
> /* ensure any other present functions are pending unplug */
> if (PCI_FUNC(pdev->devfn) == 0) {
>
--
Alexey
^ permalink raw reply [flat|nested] 4+ messages in thread* Re: [PATCH] spapr: Don't allow unplug of NVLink2 devices
2020-03-31 3:27 [PATCH] spapr: Don't allow unplug of NVLink2 devices David Gibson
2020-03-31 5:11 ` Alexey Kardashevskiy
@ 2020-03-31 7:56 ` Philippe Mathieu-Daudé
2020-03-31 10:30 ` Alexey Kardashevskiy
1 sibling, 1 reply; 4+ messages in thread
From: Philippe Mathieu-Daudé @ 2020-03-31 7:56 UTC (permalink / raw)
To: David Gibson, aik, groug; +Cc: qemu-ppc, clg, qemu-devel
On 3/31/20 5:27 AM, David Gibson wrote:
> Currently, we can't properly handle unplug of NVLink2 devices, because we
> don't have code to tear down their special memory resources. There's not
> a lot of impetus to implement that: since hardware NVLink2 devices can't
> be hot unplugged, the guest side drivers don't usually support unplug
> anyway.
>
> Therefore, simply prevent unplug of NVLink2 devices.
Safe for 5.0, right?
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
>
> Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
> ---
> hw/ppc/spapr_pci.c | 4 ++++
> 1 file changed, 4 insertions(+)
>
> diff --git a/hw/ppc/spapr_pci.c b/hw/ppc/spapr_pci.c
> index 55ca9dee1e..61b84a392d 100644
> --- a/hw/ppc/spapr_pci.c
> +++ b/hw/ppc/spapr_pci.c
> @@ -1665,6 +1665,10 @@ static void spapr_pci_unplug_request(HotplugHandler *plug_handler,
> error_setg(errp, "PCI: Hot unplug of PCI bridges not supported");
> return;
> }
> + if (object_property_get_uint(OBJECT(pdev), "nvlink2-tgt", NULL)) {
> + error_setg(errp, "PCI: Cannot unplug NVLink2 devices");
> + return;
> + }
>
> /* ensure any other present functions are pending unplug */
> if (PCI_FUNC(pdev->devfn) == 0) {
>
^ permalink raw reply [flat|nested] 4+ messages in thread* Re: [PATCH] spapr: Don't allow unplug of NVLink2 devices
2020-03-31 7:56 ` Philippe Mathieu-Daudé
@ 2020-03-31 10:30 ` Alexey Kardashevskiy
0 siblings, 0 replies; 4+ messages in thread
From: Alexey Kardashevskiy @ 2020-03-31 10:30 UTC (permalink / raw)
To: Philippe Mathieu-Daudé, David Gibson, groug
Cc: qemu-ppc, clg, qemu-devel
On 31/03/2020 18:56, Philippe Mathieu-Daudé wrote:
> On 3/31/20 5:27 AM, David Gibson wrote:
>> Currently, we can't properly handle unplug of NVLink2 devices, because we
>> don't have code to tear down their special memory resources. There's not
>> a lot of impetus to implement that: since hardware NVLink2 devices can't
>> be hot unplugged, the guest side drivers don't usually support unplug
>> anyway.
>>
>> Therefore, simply prevent unplug of NVLink2 devices.
>
> Safe for 5.0, right?
I'd say so, yes.
>
> Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
>
>>
>> Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
>> ---
>> hw/ppc/spapr_pci.c | 4 ++++
>> 1 file changed, 4 insertions(+)
>>
>> diff --git a/hw/ppc/spapr_pci.c b/hw/ppc/spapr_pci.c
>> index 55ca9dee1e..61b84a392d 100644
>> --- a/hw/ppc/spapr_pci.c
>> +++ b/hw/ppc/spapr_pci.c
>> @@ -1665,6 +1665,10 @@ static void
>> spapr_pci_unplug_request(HotplugHandler *plug_handler,
>> error_setg(errp, "PCI: Hot unplug of PCI bridges not
>> supported");
>> return;
>> }
>> + if (object_property_get_uint(OBJECT(pdev), "nvlink2-tgt",
>> NULL)) {
>> + error_setg(errp, "PCI: Cannot unplug NVLink2 devices");
>> + return;
>> + }
>> /* ensure any other present functions are pending unplug */
>> if (PCI_FUNC(pdev->devfn) == 0) {
--
Alexey
^ permalink raw reply [flat|nested] 4+ messages in thread
end of thread, other threads:[~2020-03-31 10:32 UTC | newest]
Thread overview: 4+ messages (download: mbox.gz follow: Atom feed
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2020-03-31 3:27 [PATCH] spapr: Don't allow unplug of NVLink2 devices David Gibson
2020-03-31 5:11 ` Alexey Kardashevskiy
2020-03-31 7:56 ` Philippe Mathieu-Daudé
2020-03-31 10:30 ` Alexey Kardashevskiy
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