[PATCH repost] virtio: don't crash when device is buggy

From: Michael S. Tsirkin
Date: Sun Sep 16 2012 - 05:43:01 EST



Because of a sanity check in virtio_dev_remove, a buggy device can crash
kernel. And in case of rproc it's userspace so it's not a good idea.
We are unloading a driver so how bad can it be?
Be less aggressive in handling this error: if it's a driver bug,
warning once should be enough.

Signed-off-by: Michael S. Tsirkin <mst@xxxxxxxxxx>

--

3.6 material?

diff --git a/drivers/virtio/virtio.c b/drivers/virtio/virtio.c
index c3b3f7f..1e8659c 100644
--- a/drivers/virtio/virtio.c
+++ b/drivers/virtio/virtio.c
@@ -159,7 +159,7 @@ static int virtio_dev_remove(struct device *_d)
drv->remove(dev);

/* Driver should have reset device. */
- BUG_ON(dev->config->get_status(dev));
+ WARN_ON_ONCE(dev->config->get_status(dev));

/* Acknowledge the device's existence again. */
add_status(dev, VIRTIO_CONFIG_S_ACKNOWLEDGE);

--
MST
--
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