netdev - [PATCH RFC net-next 5/5] net: stmmac: fix resume when media is in low-power mode

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: <E1tnf1c-0056LO-DN@rmk-PC.armlinux.org.uk>
Date: Thu, 27 Feb 2025 14:38:08 +0000
From: "Russell King (Oracle)" <rmk+kernel@...linux.org.uk>
To: Andrew Lunn <andrew@...n.ch>,
	Heiner Kallweit <hkallweit1@...il.com>
Cc: Alexandre Torgue <alexandre.torgue@...s.st.com>,
	Andrew Lunn <andrew+netdev@...n.ch>,
	"David S. Miller" <davem@...emloft.net>,
	Eric Dumazet <edumazet@...gle.com>,
	Jakub Kicinski <kuba@...nel.org>,
	Jon Hunter <jonathanh@...dia.com>,
	linux-arm-kernel@...ts.infradead.org,
	linux-stm32@...md-mailman.stormreply.com,
	Maxime Coquelin <mcoquelin.stm32@...il.com>,
	netdev@...r.kernel.org,
	Paolo Abeni <pabeni@...hat.com>,
	Thierry Reding <treding@...dia.com>
Subject: [PATCH RFC net-next 5/5] net: stmmac: fix resume when media is in
 low-power mode

The Synopsys Designwavre GMAC core databook requires all clocks to be
active in order to complete software reset.

This means if the PHY receive clock has been stopped due to the media
being in EEE low-power state, and the PHY being permitted to stop its
clock, then software reset will not complete.

Phylink now provides a way to work around this by calling
phylink_prepare_resume() before attempting to issue a reset. This will
prepare any attached PHY by disabling its permission to stop the clock.
phylink_resume() will restore the receive clock stop setting according
to the configuration passed from the netdev driver.

Signed-off-by: Russell King (Oracle) <rmk+kernel@...linux.org.uk>
---
 drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
index 23c610f7c779..13796b1c8d7c 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
@@ -7925,6 +7925,8 @@ int stmmac_resume(struct device *dev)
 	}

 	rtnl_lock();
+	phylink_prepare_resume(priv->phylink);
+
 	mutex_lock(&priv->lock);

 	stmmac_reset_queues_param(priv);
-- 
2.30.2