Re: [PATCH] cxbgb4: Fix build failure when CHELSIO_TLS_DEVICE=n

[Jakub Kicinski]

On Sun, 15 Nov 2020 20:31:40 -0600 Tom Seewald wrote:
> After commit 9d2e5e9eeb59 ("cxgb4/ch_ktls: decrypted bit is not enough")
> building the kernel with CHELSIO_T4=y and CHELSIO_TLS_DEVICE=n results
> in the following error:
> 
> ld: drivers/net/ethernet/chelsio/cxgb4/cxgb4_main.o: in function
> `cxgb_select_queue':
> cxgb4_main.c:(.text+0x2dac): undefined reference to `tls_validate_xmit_skb'
> 
> This is caused by cxgb_select_queue() calling cxgb4_is_ktls_skb() without
> checking if CHELSIO_TLS_DEVICE=y. Fix this by calling cxgb4_is_ktls_skb()
> only when this config option is enabled.
> 
> Fixes: 9d2e5e9eeb59 ("cxgb4/ch_ktls: decrypted bit is not enough")
> Signed-off-by: Tom Seewald <tseew...@gmail.com>
> ---
>  drivers/net/ethernet/chelsio/cxgb4/cxgb4_main.c | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/net/ethernet/chelsio/cxgb4/cxgb4_main.c 
> b/drivers/net/ethernet/chelsio/cxgb4/cxgb4_main.c
> index 7fd264a6d085..8e8783afd6df 100644
> --- a/drivers/net/ethernet/chelsio/cxgb4/cxgb4_main.c
> +++ b/drivers/net/ethernet/chelsio/cxgb4/cxgb4_main.c
> @@ -1176,7 +1176,9 @@ static u16 cxgb_select_queue(struct net_device *dev, 
> struct sk_buff *skb,
>               txq = netdev_pick_tx(dev, skb, sb_dev);
>               if (xfrm_offload(skb) || is_ptp_enabled(skb, dev) ||
>                   skb->encapsulation ||
> -                 cxgb4_is_ktls_skb(skb) ||
> +#if IS_ENABLED(CONFIG_CHELSIO_TLS_DEVICE)
> +             cxgb4_is_ktls_skb(skb) ||
> +#endif /* CHELSIO_TLS_DEVICE */
>                   (proto != IPPROTO_TCP && proto != IPPROTO_UDP))
>                       txq = txq % pi->nqsets;
>  

The tls header already tries to solve this issue, it just does it
poorly. This is a better fix:

diff --git a/include/net/tls.h b/include/net/tls.h
index baf1e99d8193..2ff3f4f7954a 100644
--- a/include/net/tls.h
+++ b/include/net/tls.h
@@ -441,11 +441,11 @@ struct sk_buff *
 tls_validate_xmit_skb(struct sock *sk, struct net_device *dev,
                      struct sk_buff *skb);
 
 static inline bool tls_is_sk_tx_device_offloaded(struct sock *sk)
 {
-#ifdef CONFIG_SOCK_VALIDATE_XMIT
+#ifdef CONFIG_TLS_DEVICE
        return sk_fullsock(sk) &&
               (smp_load_acquire(&sk->sk_validate_xmit_skb) ==
               &tls_validate_xmit_skb);
 #else
        return false;


Please test this and submit if it indeed solves the problem.

Thanks!