virtio: An entropy device, as suggested by hpa.

Note that by itself, having a "hardware" random generator does very
little: you should probably run "rngd" in your guest to feed this into
the kernel entropy pool.

Included:
	virtio_rng: dont use vmalloced addresses for virtio

	If virtio_rng is build as a module, random_data is an address
	in vmalloc space. As virtio expects guest real addresses, this
	can cause any kind of funny behaviour, so lets allocate
	random_data dynamically with kmalloc.

	Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

1 files changed, 9 insertions, 0 deletions

diff --git a/drivers/char/hw_random/Kconfig b/drivers/char/hw_random/Kconfig
index 8d6c2089d2a8..efd0b4db7c8e 100644
--- a/drivers/char/hw_random/Kconfig
+++ b/drivers/char/hw_random/Kconfig
@@ -112,3 +112,12 @@ config HW_RANDOM_PASEMI
 
           If unsure, say Y.
 
+config HW_RANDOM_VIRTIO
+        tristate "VirtIO Random Number Generator support"
+        depends on HW_RANDOM && VIRTIO
+        ---help---
+          This driver provides kernel-side support for the virtual Random Number
+          Generator hardware.
+
+          To compile this driver as a module, choose M here: the
+          module will be called virtio-rng.  If unsure, say N.