[PATCH 6.1.y] net: enetc: VFs do not support HWTSTAMP_TX_ONESTEP_SYNC

[PATCH 6.1.y] net: enetc: VFs do not support HWTSTAMP_TX_ONESTEP_SYNC

[Charles Xu]

From: Wei Fang <wei.fang@nxp.com>

[ Upstream commit a562d0c4a893eae3ea51d512c4d90ab858a6b7ec ]

Actually ENETC VFs do not support HWTSTAMP_TX_ONESTEP_SYNC because only
ENETC PF can access PMa_SINGLE_STEP registers. And there will be a crash
if VFs are used to test one-step timestamp, the crash log as follows.

[  129.110909] Unable to handle kernel paging request at virtual address 00000000000080c0
[  129.287769] Call trace:
[  129.290219]  enetc_port_mac_wr+0x30/0xec (P)
[  129.294504]  enetc_start_xmit+0xda4/0xe74
[  129.298525]  enetc_xmit+0x70/0xec
[  129.301848]  dev_hard_start_xmit+0x98/0x118

Fixes: 41514737ecaa ("enetc: add get_ts_info interface for ethtool")
Cc: stable@vger.kernel.org
Signed-off-by: Wei Fang <wei.fang@nxp.com>
Reviewed-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Tested-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Link: https://patch.msgid.link/20250224111251.1061098-5-wei.fang@nxp.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Charles Xu <charles_xu@189.cn>
---
 drivers/net/ethernet/freescale/enetc/enetc.c         | 3 +++
 drivers/net/ethernet/freescale/enetc/enetc_ethtool.c | 8 ++++++--
 2 files changed, 9 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/freescale/enetc/enetc.c b/drivers/net/ethernet/freescale/enetc/enetc.c
index bf49c07c8b51..4a516f1c2615 100644
--- a/drivers/net/ethernet/freescale/enetc/enetc.c
+++ b/drivers/net/ethernet/freescale/enetc/enetc.c
@@ -2689,6 +2689,9 @@ static int enetc_hwtstamp_set(struct net_device *ndev, struct ifreq *ifr)
 		priv->active_offloads |= ENETC_F_TX_TSTAMP;
 		break;
 	case HWTSTAMP_TX_ONESTEP_SYNC:
+		if (!enetc_si_is_pf(priv->si))
+			return -EOPNOTSUPP;
+
 		priv->active_offloads &= ~ENETC_F_TX_TSTAMP_MASK;
 		priv->active_offloads |= ENETC_F_TX_ONESTEP_SYNC_TSTAMP;
 		break;
diff --git a/drivers/net/ethernet/freescale/enetc/enetc_ethtool.c b/drivers/net/ethernet/freescale/enetc/enetc_ethtool.c
index d4623a41f013..cd51d9c49291 100644
--- a/drivers/net/ethernet/freescale/enetc/enetc_ethtool.c
+++ b/drivers/net/ethernet/freescale/enetc/enetc_ethtool.c
@@ -772,6 +772,7 @@ static int enetc_set_coalesce(struct net_device *ndev,
 static int enetc_get_ts_info(struct net_device *ndev,
 			     struct ethtool_ts_info *info)
 {
+	struct enetc_ndev_priv *priv = netdev_priv(ndev);
 	int *phc_idx;
 
 	phc_idx = symbol_get(enetc_phc_index);
@@ -791,8 +792,11 @@ static int enetc_get_ts_info(struct net_device *ndev,
 				SOF_TIMESTAMPING_SOFTWARE;
 
 	info->tx_types = (1 << HWTSTAMP_TX_OFF) |
-			 (1 << HWTSTAMP_TX_ON) |
-			 (1 << HWTSTAMP_TX_ONESTEP_SYNC);
+			 (1 << HWTSTAMP_TX_ON);
+
+	if (enetc_si_is_pf(priv->si))
+		info->tx_types |= (1 << HWTSTAMP_TX_ONESTEP_SYNC);
+
 	info->rx_filters = (1 << HWTSTAMP_FILTER_NONE) |
 			   (1 << HWTSTAMP_FILTER_ALL);
 #else
-- 
2.35.3

Re: [PATCH 6.1.y] net: enetc: VFs do not support HWTSTAMP_TX_ONESTEP_SYNC

[Greg KH]

On Mon, Apr 13, 2026 at 11:23:22AM +0800, Charles Xu wrote:
> From: Wei Fang <wei.fang@nxp.com>
> 
> [ Upstream commit a562d0c4a893eae3ea51d512c4d90ab858a6b7ec ]
> 
> Actually ENETC VFs do not support HWTSTAMP_TX_ONESTEP_SYNC because only
> ENETC PF can access PMa_SINGLE_STEP registers. And there will be a crash
> if VFs are used to test one-step timestamp, the crash log as follows.
> 
> [  129.110909] Unable to handle kernel paging request at virtual address 00000000000080c0
> [  129.287769] Call trace:
> [  129.290219]  enetc_port_mac_wr+0x30/0xec (P)
> [  129.294504]  enetc_start_xmit+0xda4/0xe74
> [  129.298525]  enetc_xmit+0x70/0xec
> [  129.301848]  dev_hard_start_xmit+0x98/0x118
> 
> Fixes: 41514737ecaa ("enetc: add get_ts_info interface for ethtool")
> Cc: stable@vger.kernel.org
> Signed-off-by: Wei Fang <wei.fang@nxp.com>
> Reviewed-by: Vladimir Oltean <vladimir.oltean@nxp.com>
> Tested-by: Vladimir Oltean <vladimir.oltean@nxp.com>
> Link: https://patch.msgid.link/20250224111251.1061098-5-wei.fang@nxp.com
> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
> Signed-off-by: Charles Xu <charles_xu@189.cn>
> ---
>  drivers/net/ethernet/freescale/enetc/enetc.c         | 3 +++
>  drivers/net/ethernet/freescale/enetc/enetc_ethtool.c | 8 ++++++--
>  2 files changed, 9 insertions(+), 2 deletions(-)

This breaks the build, ALWAYS test-build your patches.

thanks,

greg k-h