Arkadiusz Miskiewicz wrote:
On Thursday 19 of July 2007, Patrick McHardy wrote:
OK I see what the problem is. The loopback device is statically
allocated, so it doesn't have any room for the subqueues reserved.
The easiest fix would be to use egress_subqueue[1] in struct
net_device, but I think that may cause warnings with newer gccs
when using a constant index that is > 0. OTOH using constant
indices doesn't seem to make much sense for the subqueue array.
Arkadiusz, does this patch fix the problem?
It fixes the problem for me.
Thanks for testing. Dave, please apply.
[NET]: Fix loopback multiqueue bug
The loopback device is not allocated through netdev_alloc_mq and thus
has no room for the subqueue states reserved. Change the net_device
subqueue array to always include at least one element.
Signed-off-by: Patrick McHardy <[EMAIL PROTECTED]>
diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index da7a13c..bf9399c 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -575,7 +575,7 @@ struct net_device
/* The TX queue control structures */
unsigned int egress_subqueue_count;
- struct net_device_subqueue egress_subqueue[0];
+ struct net_device_subqueue egress_subqueue[1];
};
#define to_net_dev(d) container_of(d, struct net_device, dev)
diff --git a/net/core/dev.c b/net/core/dev.c
index 13a0d9f..4af0207 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -3619,7 +3619,7 @@ struct net_device *alloc_netdev_mq(int sizeof_priv, const
char *name,
/* ensure 32-byte alignment of both the device and private area */
alloc_size = (sizeof(*dev) + NETDEV_ALIGN_CONST +
- (sizeof(struct net_device_subqueue) * queue_count)) &
+ (sizeof(struct net_device_subqueue) * (queue_count - 1))) &
~NETDEV_ALIGN_CONST;
alloc_size += sizeof_priv + NETDEV_ALIGN_CONST;
@@ -3637,7 +3637,7 @@ struct net_device *alloc_netdev_mq(int sizeof_priv, const
char *name,
dev->priv = ((char *)dev +
((sizeof(struct net_device) +
(sizeof(struct net_device_subqueue) *
- queue_count) + NETDEV_ALIGN_CONST)
+ (queue_count - 1)) + NETDEV_ALIGN_CONST)
& ~NETDEV_ALIGN_CONST));
}
