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To:     "Chatre, Reinette" <reinette.chatre@intel.com>,
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Subject: RE: [PATCH V4 03/11] vfio/pci: Prepare for dynamic interrupt context
 storage
Thread-Topic: [PATCH V4 03/11] vfio/pci: Prepare for dynamic interrupt context
 storage
Thread-Index: AQHZeS7LM0WEo3lFJUe4AxtjXzq3+a9AQzGw
Date:   Fri, 28 Apr 2023 06:33:15 +0000
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> From: Chatre, Reinette <reinette.chatre@intel.com>
> Sent: Friday, April 28, 2023 1:36 AM
>
> @@ -55,17 +80,28 @@ static void vfio_send_intx_eventfd(void *opaque,
> void *unused)
>  {
>  	struct vfio_pci_core_device *vdev =3D opaque;
>=20
> -	if (likely(is_intx(vdev) && !vdev->virq_disabled))
> -		eventfd_signal(vdev->ctx[0].trigger, 1);
> +	if (likely(is_intx(vdev) && !vdev->virq_disabled)) {
> +		struct vfio_pci_irq_ctx *ctx;
> +
> +		ctx =3D vfio_irq_ctx_get(vdev, 0);
> +		if (!ctx)
> +			return;

if this error happens it implies a kernel bug since the same check
has been done in vfio_intx_enable(). Then should be a WARN_ON().

ditto for other intx functions which can be called only after intx
is enabled.