netdev - [RFC PATCH 2/2] net: phylink: Extend phylink_suspend to support a "rolling stop"

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 for Android: free password hash cracker in your pocket

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

Message-ID: 
 <174493419290.1021855.6916017022620646335.stgit@ahduyck-xeon-server.home.arpa>
Date: Thu, 17 Apr 2025 16:56:32 -0700
From: Alexander Duyck <alexander.duyck@...il.com>
To: linux@...linux.org.uk
Cc: netdev@...r.kernel.org, andrew@...n.ch, kuba@...nel.org
Subject: [RFC PATCH 2/2] net: phylink: Extend phylink_suspend to support a
 "rolling stop"

From: Alexander Duyck <alexanderduyck@...com>

The fbnic driver has been abusing the wake-on-lan aspects of
phylink_suspend to leave the MAC up when the driver is unloaded or ifconfig
down is called.

Rather than rely on wake-on-lan we can use the rolling_start flag to
indicate that the device is prone to starting/stopping with the MAC link
up, and repurpose the mac_wol to indicate that we are requesting the
mac_link_up following the suspend.

Signed-off-by: Alexander Duyck <alexanderduyck@...com>
---
 drivers/net/ethernet/meta/fbnic/fbnic_netdev.c |    5 -----
 drivers/net/phy/phylink.c                      |    9 ++++++---
 2 files changed, 6 insertions(+), 8 deletions(-)

diff --git a/drivers/net/ethernet/meta/fbnic/fbnic_netdev.c b/drivers/net/ethernet/meta/fbnic/fbnic_netdev.c
index 79a01fdd1dd1..05793811569d 100644
--- a/drivers/net/ethernet/meta/fbnic/fbnic_netdev.c
+++ b/drivers/net/ethernet/meta/fbnic/fbnic_netdev.c
@@ -685,11 +685,6 @@ struct net_device *fbnic_netdev_alloc(struct fbnic_dev *fbd)
 	netdev->min_mtu = IPV6_MIN_MTU;
 	netdev->max_mtu = FBNIC_MAX_JUMBO_FRAME_SIZE - ETH_HLEN;
 
-	/* TBD: This is workaround for BMC as phylink doesn't have support
-	 * for leavling the link enabled if a BMC is present.
-	 */
-	netdev->ethtool->wol_enabled = true;
-
 	fbn->fec = FBNIC_FEC_AUTO | FBNIC_FEC_RS;
 	fbn->link_mode = FBNIC_LINK_AUTO | FBNIC_LINK_50R2;
 	netif_carrier_off(netdev);
diff --git a/drivers/net/phy/phylink.c b/drivers/net/phy/phylink.c
index 66cd866959ef..792f9d512765 100644
--- a/drivers/net/phy/phylink.c
+++ b/drivers/net/phy/phylink.c
@@ -2526,7 +2526,7 @@ EXPORT_SYMBOL_GPL(phylink_rx_clk_stop_unblock);
 /**
  * phylink_suspend() - handle a network device suspend event
  * @pl: a pointer to a &struct phylink returned from phylink_create()
- * @mac_wol: true if the MAC needs to receive packets for Wake-on-Lan
+ * @mac_link_up: true if the MAC needs to receive packets after suspend
  *
  * Handle a network device suspend event. There are several cases:
  *
@@ -2536,12 +2536,15 @@ EXPORT_SYMBOL_GPL(phylink_rx_clk_stop_unblock);
  *   can also bring down the link between the MAC and PHY.
  * - If Wake-on-Lan is active, but being handled by the MAC, the MAC
  *   still needs to receive packets, so we can not bring the link down.
+ * - If rolling_start is requested, and the MAC is shared with a BMC, the MAC
+ *   still needs to receive packets, so we can not bring the link down.
  */
-void phylink_suspend(struct phylink *pl, bool mac_wol)
+void phylink_suspend(struct phylink *pl, bool mac_link_up)
 {
 	ASSERT_RTNL();
 
-	if (mac_wol && (!pl->netdev || pl->netdev->ethtool->wol_enabled)) {
+	if (mac_link_up && (!pl->netdev || pl->netdev->ethtool->wol_enabled ||
+			    pl->config->rolling_start)) {
 		/* Wake-on-Lan enabled, MAC handling */
 		mutex_lock(&pl->state_mutex);