Re: [PATCH 21/28] net/hyperv: avoid uninitialized variable

From: David Miller
Date: Tue Oct 18 2016 - 14:21:27 EST


From: Arnd Bergmann <arnd@xxxxxxxx>
Date: Tue, 18 Oct 2016 00:16:09 +0200

> 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 ʽnetvsc_start_xmitʼ:
> drivers/net/hyperv/netvsc_drv.c:494:42: error: ʽhdr_offsetʼ 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>

Applied.