From 3fff0179e33cd7d0a688dab65700c46ad089e934 Mon Sep 17 00:00:00 2001 From: Mark McLoughlin <markmc@redhat.com> Date: Tue, 3 Feb 2009 13:33:53 +1030 Subject: [PATCH] virtio-pci: do not oops on config change if driver not loaded The host really shouldn't be notifying us of config changes before the device status is VIRTIO_CONFIG_S_DRIVER or VIRTIO_CONFIG_S_DRIVER_OK. However, if we do happen to be interrupted while we're not attached to a driver, we really shouldn't oops. Prevent this simply by checking that device->driver is non-NULL before trying to notify the driver of config changes. Problem observed by doing a "set_link virtio.0 down" with QEMU before the net driver had been loaded. Signed-off-by: Mark McLoughlin <markmc@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> --- drivers/virtio/virtio_pci.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/virtio/virtio_pci.c b/drivers/virtio/virtio_pci.c index bef6b45e8a5c..330aacbdec1f 100644 --- a/drivers/virtio/virtio_pci.c +++ b/drivers/virtio/virtio_pci.c @@ -192,7 +192,7 @@ static irqreturn_t vp_interrupt(int irq, void *opaque) drv = container_of(vp_dev->vdev.dev.driver, struct virtio_driver, driver); - if (drv->config_changed) + if (drv && drv->config_changed) drv->config_changed(&vp_dev->vdev); }