diff mbox series

ch_ktls: fix build warning for ipv4-only config

Message ID 20201203222641.964234-1-arnd@kernel.org
State New
Headers show
Series ch_ktls: fix build warning for ipv4-only config | expand

Commit Message

Arnd Bergmann Dec. 3, 2020, 10:26 p.m. UTC
From: Arnd Bergmann <arnd@arndb.de>


When CONFIG_IPV6 is disabled, clang complains that a variable
is uninitialized for non-IPv4 data:

drivers/net/ethernet/chelsio/inline_crypto/ch_ktls/chcr_ktls.c:1046:6: error: variable 'cntrl1' is used uninitialized whenever 'if' condition is false [-Werror,-Wsometimes-uninitialized]
        if (tx_info->ip_family == AF_INET) {
            ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
drivers/net/ethernet/chelsio/inline_crypto/ch_ktls/chcr_ktls.c:1059:2: note: uninitialized use occurs here
        cntrl1 |= T6_TXPKT_ETHHDR_LEN_V(maclen - ETH_HLEN) |
        ^~~~~~

Replace the preprocessor conditional with the corresponding C version,
and make the ipv4 case unconditional in this configuration to improve
readability and avoid the warning.

Fixes: 86716b51d14f ("ch_ktls: Update cheksum information")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

---
 .../net/ethernet/chelsio/inline_crypto/ch_ktls/chcr_ktls.c  | 6 +-----
 1 file changed, 1 insertion(+), 5 deletions(-)

-- 
2.27.0

Comments

Jakub Kicinski Dec. 5, 2020, 1:57 a.m. UTC | #1
On Thu,  3 Dec 2020 23:26:16 +0100 Arnd Bergmann wrote:
> From: Arnd Bergmann <arnd@arndb.de>

> 

> When CONFIG_IPV6 is disabled, clang complains that a variable

> is uninitialized for non-IPv4 data:

> 

> drivers/net/ethernet/chelsio/inline_crypto/ch_ktls/chcr_ktls.c:1046:6: error: variable 'cntrl1' is used uninitialized whenever 'if' condition is false [-Werror,-Wsometimes-uninitialized]

>         if (tx_info->ip_family == AF_INET) {

>             ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~

> drivers/net/ethernet/chelsio/inline_crypto/ch_ktls/chcr_ktls.c:1059:2: note: uninitialized use occurs here

>         cntrl1 |= T6_TXPKT_ETHHDR_LEN_V(maclen - ETH_HLEN) |

>         ^~~~~~

> 

> Replace the preprocessor conditional with the corresponding C version,

> and make the ipv4 case unconditional in this configuration to improve

> readability and avoid the warning.

> 

> Fixes: 86716b51d14f ("ch_ktls: Update cheksum information")

> Signed-off-by: Arnd Bergmann <arnd@arndb.de>


This is for evrey clang build or just W=1+? Would be annoying if clang
produced this on every build with 5.10 (we need to decide fix vs -next).
patchwork-bot+netdevbpf@kernel.org Dec. 5, 2020, 9 p.m. UTC | #2
Hello:

This patch was applied to netdev/net.git (refs/heads/master):

On Thu,  3 Dec 2020 23:26:16 +0100 you wrote:
> From: Arnd Bergmann <arnd@arndb.de>

> 

> When CONFIG_IPV6 is disabled, clang complains that a variable

> is uninitialized for non-IPv4 data:

> 

> drivers/net/ethernet/chelsio/inline_crypto/ch_ktls/chcr_ktls.c:1046:6: error: variable 'cntrl1' is used uninitialized whenever 'if' condition is false [-Werror,-Wsometimes-uninitialized]

>         if (tx_info->ip_family == AF_INET) {

>             ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~

> drivers/net/ethernet/chelsio/inline_crypto/ch_ktls/chcr_ktls.c:1059:2: note: uninitialized use occurs here

>         cntrl1 |= T6_TXPKT_ETHHDR_LEN_V(maclen - ETH_HLEN) |

>         ^~~~~~

> 

> [...]


Here is the summary with links:
  - ch_ktls: fix build warning for ipv4-only config
    https://git.kernel.org/netdev/net/c/a54ba3465d86

You are awesome, thank you!
--
Deet-doot-dot, I am a bot.
https://korg.docs.kernel.org/patchwork/pwbot.html
Arnd Bergmann Dec. 5, 2020, 11:18 p.m. UTC | #3
On Sat, Dec 5, 2020 at 2:57 AM Jakub Kicinski <kuba@kernel.org> wrote:
>

> On Thu,  3 Dec 2020 23:26:16 +0100 Arnd Bergmann wrote:

> > From: Arnd Bergmann <arnd@arndb.de>

> >

> > When CONFIG_IPV6 is disabled, clang complains that a variable

> > is uninitialized for non-IPv4 data:

> >

> > drivers/net/ethernet/chelsio/inline_crypto/ch_ktls/chcr_ktls.c:1046:6: error: variable 'cntrl1' is used uninitialized whenever 'if' condition is false [-Werror,-Wsometimes-uninitialized]

> >         if (tx_info->ip_family == AF_INET) {

> >             ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~

> > drivers/net/ethernet/chelsio/inline_crypto/ch_ktls/chcr_ktls.c:1059:2: note: uninitialized use occurs here

> >         cntrl1 |= T6_TXPKT_ETHHDR_LEN_V(maclen - ETH_HLEN) |

> >         ^~~~~~

> >

> > Replace the preprocessor conditional with the corresponding C version,

> > and make the ipv4 case unconditional in this configuration to improve

> > readability and avoid the warning.

> >

> > Fixes: 86716b51d14f ("ch_ktls: Update cheksum information")

> > Signed-off-by: Arnd Bergmann <arnd@arndb.de>

>

> This is for evrey clang build or just W=1+? Would be annoying if clang

> produced this on every build with 5.10 (we need to decide fix vs -next).


The -Wsometimes-uninitialized is enabled unconditionally for clang,
but this only happens for IPv4-only configurations with IPv6 disabled,
so most real configurations should not observe it, but the fix should still
go into v5.10.

      Arnd
Jakub Kicinski Dec. 5, 2020, 11:23 p.m. UTC | #4
On Sun, 6 Dec 2020 00:18:44 +0100 Arnd Bergmann wrote:
> > This is for evrey clang build or just W=1+? Would be annoying if clang

> > produced this on every build with 5.10 (we need to decide fix vs -next).  

> 

> The -Wsometimes-uninitialized is enabled unconditionally for clang,

> but this only happens for IPv4-only configurations with IPv6 disabled,

> so most real configurations should not observe it, but the fix should still

> go into v5.10.


Great, I guessed correctly :)
diff mbox series

Patch

diff --git a/drivers/net/ethernet/chelsio/inline_crypto/ch_ktls/chcr_ktls.c b/drivers/net/ethernet/chelsio/inline_crypto/ch_ktls/chcr_ktls.c
index 7f90b828d159..1b7e8c91b541 100644
--- a/drivers/net/ethernet/chelsio/inline_crypto/ch_ktls/chcr_ktls.c
+++ b/drivers/net/ethernet/chelsio/inline_crypto/ch_ktls/chcr_ktls.c
@@ -987,9 +987,7 @@  chcr_ktls_write_tcp_options(struct chcr_ktls_info *tx_info, struct sk_buff *skb,
 	struct fw_eth_tx_pkt_wr *wr;
 	struct cpl_tx_pkt_core *cpl;
 	u32 ctrl, iplen, maclen;
-#if IS_ENABLED(CONFIG_IPV6)
 	struct ipv6hdr *ip6;
-#endif
 	unsigned int ndesc;
 	struct tcphdr *tcp;
 	int len16, pktlen;
@@ -1043,17 +1041,15 @@  chcr_ktls_write_tcp_options(struct chcr_ktls_info *tx_info, struct sk_buff *skb,
 	cpl->len = htons(pktlen);
 
 	memcpy(buf, skb->data, pktlen);
-	if (tx_info->ip_family == AF_INET) {
+	if (!IS_ENABLED(CONFIG_IPV6) || tx_info->ip_family == AF_INET) {
 		/* we need to correct ip header len */
 		ip = (struct iphdr *)(buf + maclen);
 		ip->tot_len = htons(pktlen - maclen);
 		cntrl1 = TXPKT_CSUM_TYPE_V(TX_CSUM_TCPIP);
-#if IS_ENABLED(CONFIG_IPV6)
 	} else {
 		ip6 = (struct ipv6hdr *)(buf + maclen);
 		ip6->payload_len = htons(pktlen - maclen - iplen);
 		cntrl1 = TXPKT_CSUM_TYPE_V(TX_CSUM_TCPIP6);
-#endif
 	}
 
 	cntrl1 |= T6_TXPKT_ETHHDR_LEN_V(maclen - ETH_HLEN) |