The hdr_offset variable is only if we deal with a TCP or UDP packet, but as the check surrounding its usage tests for skb_is_gso() instead, the compiler has no idea if the variable is initialized or not at that point: drivers/net/hyperv/netvsc_drv.c: In function ‘netvsc_start_xmit’: drivers/net/hyperv/netvsc_drv.c:494:42: error: ‘hdr_offset’ may be used uninitialized in this function [-Werror=maybe-uninitialized] This adds an additional check for the transport type, which tells the compiler that this path cannot happen. Since the get_net_transport_info() function should always be inlined here, I don't expect this to result in additional runtime checks. Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx> --- drivers/net/hyperv/netvsc_drv.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/net/hyperv/netvsc_drv.c b/drivers/net/hyperv/netvsc_drv.c index f0919bd..5d6e75a 100644 --- a/drivers/net/hyperv/netvsc_drv.c +++ b/drivers/net/hyperv/netvsc_drv.c @@ -447,7 +447,7 @@ static int netvsc_start_xmit(struct sk_buff *skb, struct net_device *net) * Setup the sendside checksum offload only if this is not a * GSO packet. */ - if (skb_is_gso(skb)) { + if ((net_trans_info & (INFO_TCP | INFO_UDP)) && skb_is_gso(skb)) { struct ndis_tcp_lso_info *lso_info; rndis_msg_size += NDIS_LSO_PPI_SIZE; -- 2.9.0 _______________________________________________ devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxx http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel