On Wed, Oct 23, 2019 at 12:06:48PM -0600, Alex Williamson wrote:
On Wed, 23 Oct 2019 10:27:02 +0200
Jens Freimann <jfreim...@redhat.com> wrote:
This patch adds a net_failover_pair_id property to PCIDev which is
used to link the primary device in a failover pair (the PCI dev) to
a standby (a virtio-net-pci) device.
It only supports ethernet devices. Also currently it only supports
PCIe devices. QEMU will exit with an error message otherwise.
Signed-off-by: Jens Freimann <jfreim...@redhat.com>
---
hw/pci/pci.c | 17 +++++++++++++++++
include/hw/pci/pci.h | 3 +++
2 files changed, 20 insertions(+)
diff --git a/hw/pci/pci.c b/hw/pci/pci.c
index aa05c2b9b2..fa9b5219f8 100644
--- a/hw/pci/pci.c
+++ b/hw/pci/pci.c
@@ -75,6 +75,8 @@ static Property pci_props[] = {
QEMU_PCIE_LNKSTA_DLLLA_BITNR, true),
DEFINE_PROP_BIT("x-pcie-extcap-init", PCIDevice, cap_present,
QEMU_PCIE_EXTCAP_INIT_BITNR, true),
+ DEFINE_PROP_STRING("net_failover_pair_id", PCIDevice,
+ net_failover_pair_id),
Nit, white space appears broken here.
I'll fix it.
DEFINE_PROP_END_OF_LIST()
};
@@ -2077,6 +2079,7 @@ static void pci_qdev_realize(DeviceState *qdev, Error
**errp)
ObjectClass *klass = OBJECT_CLASS(pc);
Error *local_err = NULL;
bool is_default_rom;
+ uint16_t class_id;
/* initialize cap_present for pci_is_express() and pci_config_size(),
* Note that hybrid PCIs are not set automatically and need to manage
@@ -2101,6 +2104,20 @@ static void pci_qdev_realize(DeviceState *qdev, Error
**errp)
}
}
+ if (pci_dev->net_failover_pair_id) {
+ if (!pci_is_express(pci_dev)) {
+ error_setg(errp, "failover device is not a PCIExpress device");
+ error_propagate(errp, local_err);
+ return;
+ }
Did we decide we don't need to test that the device is also in a
hotpluggable slot?
Hmm, my reply to you was never sent. I thought the check for
qdev_device_add() was sufficient but you said that works only
after qdev_hotplug is set (after machine creation). I modified
the check to this:
hide = should_hide_device(opts);
if ((hide || qdev_hotplug) && bus && !qbus_is_hotpluggable(bus)) {
error_setg(errp, QERR_BUS_NO_HOTPLUG, bus->name);
return NULL;
}
if (hide) {
return NULL;
}
This will make qemu fail when we have the device in the initial
configuration or when we hotplug it to a bus that doesn't support it.
I tested both with a device on pcie.0. Am I missing something?
Are there also multi-function considerations that
should be prevented or documented? For example, if a user tries to
configure both the primary and failover NICs in the same slot, I assume
bad things will happen.
I would have expected that this is already checked in pci code, but
it is not. I tried it and when I put both devices into the same slot
they are both unplugged from the guest during boot but nothing else
happens. I don't know what triggers that unplug of the devices.
I'm not aware of any other problems regarding multi-function, which
doesn't mean there aren't any.
+ class_id = pci_get_word(pci_dev->config + PCI_CLASS_DEVICE);
+ if (class_id != PCI_CLASS_NETWORK_ETHERNET) {
+ error_setg(errp, "failover device is not an Ethernet device");
+ error_propagate(errp, local_err);
+ return;
+ }
+ }
Looks like cleanup is missing both both error cases, the option rom
error path below this does a pci_qdev_unrealize() before returning so
I'd assume we want the same here. Thanks,
Thanks, I'll fix this too.
regards,
Jens
