[v1] vfio-user: reject failover during init

[PATCH] vfio-user: reject failover during init

Posted by Hugo Komatsu 1 week, 6 days ago

Virtio-net failover is a networking feature that relies on a primary
and standby device pair. This is not currently supported for vfio-user.
Refuse initialization if this property is set.

Change-Id: I80989ddb08a1cd3eba84bcf9b0edc26cb4a65669
Signed-off-by: Hugo Komatsu <hugo.komatsu@nutanix.com>
---
 hw/vfio-user/pci.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/hw/vfio-user/pci.c b/hw/vfio-user/pci.c
index ecc59a9642..34fa2f22b3 100644
--- a/hw/vfio-user/pci.c
+++ b/hw/vfio-user/pci.c
@@ -251,6 +251,11 @@ static void vfio_user_pci_realize(PCIDevice *pdev, Error **errp)
         return;
     }
 
+    if (pdev->failover_pair_id) {
+        error_setg(errp, "vfio-user: failover is not supported");
+        return;
+    }
+
     sock_name = udev->socket->u.q_unix.path;
 
     vbasedev->name = g_strdup_printf("vfio-user:%s", sock_name);
-- 
2.39.3

RE: [PATCH] vfio-user: reject failover during init

Posted by Thanos Makatos 1 week, 5 days ago

> -----Original Message-----
> From: Hugo Komatsu <hugo.komatsu@nutanix.com>
> Sent: 13 August 2026 12:31
> To: John Levon <john.levon@nutanix.com>; Thanos Makatos
> <thanos.makatos@nutanix.com>; Cédric Le Goater <clg@redhat.com>;
> qemu-devel@nongnu.org
> Cc: Hugo Komatsu <hugo.komatsu@nutanix.com>
> Subject: [PATCH] vfio-user: reject failover during init
> 
> Virtio-net failover is a networking feature that relies on a primary
> and standby device pair. This is not currently supported for vfio-user.
> Refuse initialization if this property is set.
> 
> Change-Id: I80989ddb08a1cd3eba84bcf9b0edc26cb4a65669
> Signed-off-by: Hugo Komatsu <hugo.komatsu@nutanix.com>
> ---
>  hw/vfio-user/pci.c | 5 +++++
>  1 file changed, 5 insertions(+)
> 
> diff --git a/hw/vfio-user/pci.c b/hw/vfio-user/pci.c
> index ecc59a9642..34fa2f22b3 100644
> --- a/hw/vfio-user/pci.c
> +++ b/hw/vfio-user/pci.c
> @@ -251,6 +251,11 @@ static void vfio_user_pci_realize(PCIDevice *pdev,
> Error **errp)
>          return;
>      }
> 
> +    if (pdev->failover_pair_id) {
> +        error_setg(errp, "vfio-user: failover is not supported");
> +        return;
> +    }
> +
>      sock_name = udev->socket->u.q_unix.path;
> 
>      vbasedev->name = g_strdup_printf("vfio-user:%s", sock_name);
> --
> 2.39.3

LGTM except the ChangeId John mentioned.

Reviewed-by: Thanos Makatos <thanos.makatos@nutanix.com>

Re: [PATCH] vfio-user: reject failover during init

Posted by Hugo Komatsu 1 week, 5 days ago

Thanks Thanos and I actually fired off a v2 to the list yesterday that drops the Change-Id per John's feedback.
________________________________
From: Thanos Makatos <thanos.makatos@nutanix.com>
Sent: Friday, August 14, 2026 7:29 AM
To: Hugo Komatsu <hugo.komatsu@nutanix.com>; John Levon <john.levon@nutanix.com>; Cédric Le Goater <clg@redhat.com>; qemu-devel@nongnu.org <qemu-devel@nongnu.org>
Subject: RE: [PATCH] vfio-user: reject failover during init

> -----Original Message-----
> From: Hugo Komatsu <hugo.komatsu@nutanix.com>
> Sent: 13 August 2026 12:31
> To: John Levon <john.levon@nutanix.com>; Thanos Makatos
> <thanos.makatos@nutanix.com>; Cédric Le Goater <clg@redhat.com>;
> qemu-devel@nongnu.org
> Cc: Hugo Komatsu <hugo.komatsu@nutanix.com>
> Subject: [PATCH] vfio-user: reject failover during init
>
> Virtio-net failover is a networking feature that relies on a primary
> and standby device pair. This is not currently supported for vfio-user.
> Refuse initialization if this property is set.
>
> Change-Id: I80989ddb08a1cd3eba84bcf9b0edc26cb4a65669
> Signed-off-by: Hugo Komatsu <hugo.komatsu@nutanix.com>
> ---
>  hw/vfio-user/pci.c | 5 +++++
>  1 file changed, 5 insertions(+)
>
> diff --git a/hw/vfio-user/pci.c b/hw/vfio-user/pci.c
> index ecc59a9642..34fa2f22b3 100644
> --- a/hw/vfio-user/pci.c
> +++ b/hw/vfio-user/pci.c
> @@ -251,6 +251,11 @@ static void vfio_user_pci_realize(PCIDevice *pdev,
> Error **errp)
>          return;
>      }
>
> +    if (pdev->failover_pair_id) {
> +        error_setg(errp, "vfio-user: failover is not supported");
> +        return;
> +    }
> +
>      sock_name = udev->socket->u.q_unix.path;
>
>      vbasedev->name = g_strdup_printf("vfio-user:%s", sock_name);
> --
> 2.39.3

LGTM except the ChangeId John mentioned.

Reviewed-by: Thanos Makatos <thanos.makatos@nutanix.com>

Re: [PATCH] vfio-user: reject failover during init

Posted by John Levon 1 week, 6 days ago

On Thu, Aug 13, 2026 at 10:30:44AM +0100, Hugo Komatsu wrote:

> Virtio-net failover is a networking feature that relies on a primary
> and standby device pair. This is not currently supported for vfio-user.
> Refuse initialization if this property is set.
> 
> Change-Id: I80989ddb08a1cd3eba84bcf9b0edc26cb4a65669

Please drop the Change-Id, that's a gerrit thing.

Otherwise, 

Reviewed-by: John Levon <john.levon@nutanix.com>

regards
john