diff options
| author | Andrew Lunn <andrew@lunn.ch> | 2024-11-10 20:59:55 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2024-12-14 22:03:55 +0300 |
| commit | 1ab42ad28076304f88485d22f1230b6c77030a35 (patch) | |
| tree | 48178a65db9a6be5b1b09ab0b246ae3e0657eb11 /drivers/net/dsa/qca | |
| parent | 9fbc0ece455e2c008568266f39f9d14628ac3803 (diff) | |
| download | linux-1ab42ad28076304f88485d22f1230b6c77030a35.tar.xz | |
dsa: qca8k: Use nested lock to avoid splat
[ Upstream commit 078e0d596f7b5952dad8662ace8f20ed2165e2ce ]
qca8k_phy_eth_command() is used to probe the child MDIO bus while the
parent MDIO is locked. This causes lockdep splat, reporting a possible
deadlock. It is not an actually deadlock, because different locks are
used. By making use of mutex_lock_nested() we can avoid this false
positive.
Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Link: https://patch.msgid.link/20241110175955.3053664-1-andrew@lunn.ch
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'drivers/net/dsa/qca')
| -rw-r--r-- | drivers/net/dsa/qca/qca8k-8xxx.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/drivers/net/dsa/qca/qca8k-8xxx.c b/drivers/net/dsa/qca/qca8k-8xxx.c index f8d8c70642c4..59b4a7240b58 100644 --- a/drivers/net/dsa/qca/qca8k-8xxx.c +++ b/drivers/net/dsa/qca/qca8k-8xxx.c @@ -673,7 +673,7 @@ qca8k_phy_eth_command(struct qca8k_priv *priv, bool read, int phy, * We therefore need to lock the MDIO bus onto which the switch is * connected. */ - mutex_lock(&priv->bus->mdio_lock); + mutex_lock_nested(&priv->bus->mdio_lock, MDIO_MUTEX_NESTED); /* Actually start the request: * 1. Send mdio master packet |