diff mbox series

[v2] net: dsa: tag_brcm: legacy: fix daisy-chained switches

Message ID 20230319095540.239064-1-noltari@gmail.com (mailing list archive)
State Accepted
Commit 032a954061afd4b7426c3eb6bfd2952ef1e9a384
Delegated to: Netdev Maintainers
Headers show
Series [v2] net: dsa: tag_brcm: legacy: fix daisy-chained switches | expand

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Context Check Description
netdev/series_format warning Single patches do not need cover letters; Target tree name not specified in the subject
netdev/tree_selection success Guessed tree name to be net-next
netdev/fixes_present success Fixes tag not required for -next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 18 this patch: 18
netdev/cc_maintainers success CCed 9 of 9 maintainers
netdev/build_clang success Errors and warnings before: 18 this patch: 18
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/deprecated_api success None detected
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success Fixes tag looks correct
netdev/build_allmodconfig_warn success Errors and warnings before: 18 this patch: 18
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 32 lines checked
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0

Commit Message

Álvaro Fernández Rojas March 19, 2023, 9:55 a.m. UTC
When BCM63xx internal switches are connected to switches with a 4-byte
Broadcom tag, it does not identify the packet as VLAN tagged, so it adds one
based on its PVID (which is likely 0).
Right now, the packet is received by the BCM63xx internal switch and the 6-byte
tag is properly processed. The next step would to decode the corresponding
4-byte tag. However, the internal switch adds an invalid VLAN tag after the
6-byte tag and the 4-byte tag handling fails.
In order to fix this we need to remove the invalid VLAN tag after the 6-byte
tag before passing it to the 4-byte tag decoding.

Fixes: 964dbf186eaa ("net: dsa: tag_brcm: add support for legacy tags")
Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>
Reviewed-by: Michal Swiatkowski <michal.swiatkowski@linux.intel.com>
---
 v2: add missing fixes tag.

 net/dsa/tag_brcm.c | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

Comments

Jakub Kicinski March 21, 2023, 1:58 a.m. UTC | #1
On Sun, 19 Mar 2023 10:55:40 +0100 Álvaro Fernández Rojas wrote:
> When BCM63xx internal switches are connected to switches with a 4-byte
> Broadcom tag, it does not identify the packet as VLAN tagged, so it adds one
> based on its PVID (which is likely 0).
> Right now, the packet is received by the BCM63xx internal switch and the 6-byte
> tag is properly processed. The next step would to decode the corresponding
> 4-byte tag. However, the internal switch adds an invalid VLAN tag after the
> 6-byte tag and the 4-byte tag handling fails.
> In order to fix this we need to remove the invalid VLAN tag after the 6-byte
> tag before passing it to the 4-byte tag decoding.

Is it good to go in, Florian?
Florian Fainelli March 21, 2023, 8:51 p.m. UTC | #2
On 3/19/23 02:55, Álvaro Fernández Rojas wrote:
> When BCM63xx internal switches are connected to switches with a 4-byte
> Broadcom tag, it does not identify the packet as VLAN tagged, so it adds one
> based on its PVID (which is likely 0).
> Right now, the packet is received by the BCM63xx internal switch and the 6-byte
> tag is properly processed. The next step would to decode the corresponding
> 4-byte tag. However, the internal switch adds an invalid VLAN tag after the
> 6-byte tag and the 4-byte tag handling fails.
> In order to fix this we need to remove the invalid VLAN tag after the 6-byte
> tag before passing it to the 4-byte tag decoding.
> 
> Fixes: 964dbf186eaa ("net: dsa: tag_brcm: add support for legacy tags")
> Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>
> Reviewed-by: Michal Swiatkowski <michal.swiatkowski@linux.intel.com>

Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
patchwork-bot+netdevbpf@kernel.org March 22, 2023, 12:40 a.m. UTC | #3
Hello:

This patch was applied to netdev/net.git (main)
by Jakub Kicinski <kuba@kernel.org>:

On Sun, 19 Mar 2023 10:55:40 +0100 you wrote:
> When BCM63xx internal switches are connected to switches with a 4-byte
> Broadcom tag, it does not identify the packet as VLAN tagged, so it adds one
> based on its PVID (which is likely 0).
> Right now, the packet is received by the BCM63xx internal switch and the 6-byte
> tag is properly processed. The next step would to decode the corresponding
> 4-byte tag. However, the internal switch adds an invalid VLAN tag after the
> 6-byte tag and the 4-byte tag handling fails.
> In order to fix this we need to remove the invalid VLAN tag after the 6-byte
> tag before passing it to the 4-byte tag decoding.
> 
> [...]

Here is the summary with links:
  - [v2] net: dsa: tag_brcm: legacy: fix daisy-chained switches
    https://git.kernel.org/netdev/net/c/032a954061af

You are awesome, thank you!
diff mbox series

Patch

diff --git a/net/dsa/tag_brcm.c b/net/dsa/tag_brcm.c
index 10239daa5745..cacdafb41200 100644
--- a/net/dsa/tag_brcm.c
+++ b/net/dsa/tag_brcm.c
@@ -7,6 +7,7 @@ 
 
 #include <linux/dsa/brcm.h>
 #include <linux/etherdevice.h>
+#include <linux/if_vlan.h>
 #include <linux/list.h>
 #include <linux/slab.h>
 
@@ -252,6 +253,7 @@  static struct sk_buff *brcm_leg_tag_xmit(struct sk_buff *skb,
 static struct sk_buff *brcm_leg_tag_rcv(struct sk_buff *skb,
 					struct net_device *dev)
 {
+	int len = BRCM_LEG_TAG_LEN;
 	int source_port;
 	u8 *brcm_tag;
 
@@ -266,12 +268,16 @@  static struct sk_buff *brcm_leg_tag_rcv(struct sk_buff *skb,
 	if (!skb->dev)
 		return NULL;
 
+	/* VLAN tag is added by BCM63xx internal switch */
+	if (netdev_uses_dsa(skb->dev))
+		len += VLAN_HLEN;
+
 	/* Remove Broadcom tag and update checksum */
-	skb_pull_rcsum(skb, BRCM_LEG_TAG_LEN);
+	skb_pull_rcsum(skb, len);
 
 	dsa_default_offload_fwd_mark(skb);
 
-	dsa_strip_etype_header(skb, BRCM_LEG_TAG_LEN);
+	dsa_strip_etype_header(skb, len);
 
 	return skb;
 }