linux-kernel - [PATCH net-next 1/2] net: dsa: tag

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20260119185935.2072685-2-mmyangfl@gmail.com>
Date: Tue, 20 Jan 2026 02:59:29 +0800
From: David Yang <mmyangfl@...il.com>
To: netdev@...r.kernel.org
Cc: David Yang <mmyangfl@...il.com>,
	Andrew Lunn <andrew@...n.ch>,
	Vladimir Oltean <olteanv@...il.com>,
	"David S. Miller" <davem@...emloft.net>,
	Eric Dumazet <edumazet@...gle.com>,
	Jakub Kicinski <kuba@...nel.org>,
	Paolo Abeni <pabeni@...hat.com>,
	Simon Horman <horms@...nel.org>,
	Russell King <linux@...linux.org.uk>,
	linux-kernel@...r.kernel.org
Subject: [PATCH net-next 1/2] net: dsa: tag_yt921x: fix priority support

The packet priority is embedded in the rx tag. It defaults to 0, but
adding DCB support to the switch driver will break the tag driver by
setting it to non-zero.

Signed-off-by: David Yang <mmyangfl@...il.com>
---
 net/dsa/tag_yt921x.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/net/dsa/tag_yt921x.c b/net/dsa/tag_yt921x.c
index 6bbfd42dc5df..b93715a057c7 100644
--- a/net/dsa/tag_yt921x.c
+++ b/net/dsa/tag_yt921x.c
@@ -17,7 +17,8 @@
  *   2: Rx Port
  *     15b: Rx Port Valid
  *     14b-11b: Rx Port
- *     10b-0b: Cmd?
+ *     10b-8b: Priority
+ *     7b-0b: Cmd
  *   2: Tx Port(s)
  *     15b: Tx Port(s) Valid
  *     10b-0b: Tx Port(s) Mask
@@ -33,7 +34,8 @@
 
 #define YT921X_TAG_PORT_EN		BIT(15)
 #define YT921X_TAG_RX_PORT_M		GENMASK(14, 11)
-#define YT921X_TAG_RX_CMD_M		GENMASK(10, 0)
+#define YT921X_TAG_RX_PRIO_M		GENMASK(10, 8)
+#define YT921X_TAG_RX_CMD_M		GENMASK(7, 0)
 #define  YT921X_TAG_RX_CMD(x)			FIELD_PREP(YT921X_TAG_RX_CMD_M, (x))
 #define  YT921X_TAG_RX_CMD_FORWARDED		0x80
 #define  YT921X_TAG_RX_CMD_UNK_UCAST		0xb2
@@ -98,6 +100,8 @@ yt921x_tag_rcv(struct sk_buff *skb, struct net_device *netdev)
 		return NULL;
 	}
 
+	skb->priority = FIELD_GET(YT921X_TAG_RX_PRIO_M, rx);
+
 	cmd = FIELD_GET(YT921X_TAG_RX_CMD_M, rx);
 	switch (cmd) {
 	case YT921X_TAG_RX_CMD_FORWARDED:
-- 
2.51.0