From: Sjur Brændeland <[email protected]> Fix panic in virtio.c when CONFIG_DEBUG_SLAB is set. device_unregister() drops reference to device so put_device() could invoke release callback. In this case the release callback will free the device. Make sure we don't access device after unregister by fetching the device index before calling unregister.
Signed-off-by: Sjur Brændeland <[email protected]> cc: Guzman Lugo, Fernadndo <[email protected]> cc: Michael S. Tsirkin <[email protected]> cc: Rusty Russell <[email protected]> cc: Ohad Ben-Cohen <[email protected]> cc: [email protected] cc: [email protected] --- drivers/virtio/virtio.c | 9 ++++++++- 1 files changed, 8 insertions(+), 1 deletions(-) diff --git a/drivers/virtio/virtio.c b/drivers/virtio/virtio.c index c3b3f7f..faee112 100644 --- a/drivers/virtio/virtio.c +++ b/drivers/virtio/virtio.c @@ -225,8 +225,15 @@ EXPORT_SYMBOL_GPL(register_virtio_device); void unregister_virtio_device(struct virtio_device *dev) { + /* + * device_unregister() drops reference to device so put_device could + * invoke release callback. In case that callback will free the device, + * make sure we don't access device after this call. + */ + + int index = dev->index; device_unregister(&dev->dev); - ida_simple_remove(&virtio_index_ida, dev->index); + ida_simple_remove(&virtio_index_ida, index); } EXPORT_SYMBOL_GPL(unregister_virtio_device); -- 1.7.5.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
