From: Greg KH on
2.6.32-stable review patch. If anyone has any objections, please let us know.


From: Sridhar Samudrala <sri(a)>

(Cherry-picked from commit e80e2a60ff7914dae691345a976c80bbbff3ec74)

This patch increases the current hardcoded limit of NR_IOBUS_DEVS
from 6 to 200. We are hitting this limit when creating a guest with more
than 1 virtio-net device using vhost-net backend. Each virtio-net
device requires 2 such devices to service notifications from rx/tx queues.

Signed-off-by: Sridhar Samudrala <sri(a)>
Signed-off-by: Avi Kivity <avi(a)>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)>

include/linux/kvm_host.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -53,7 +53,7 @@ extern struct kmem_cache *kvm_vcpu_cache
struct kvm_io_bus {
int dev_count;
-#define NR_IOBUS_DEVS 6
+#define NR_IOBUS_DEVS 200
struct kvm_io_device *devs[NR_IOBUS_DEVS];

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