This is a note to let you know that I've just added the patch titled

net: phy: Restore phy_resume() locking assumption

to the 4.14-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git%3Ba=su...

The filename of the patch is: net-phy-restore-phy_resume-locking-assumption.patch and it can be found in the queue-4.14 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let stable@vger.kernel.org know about it.

From 9c2c2e62df3fa30fb13fbeb7512a4eede729383b Mon Sep 17 00:00:00 2001

From: Andrew Lunn andrew@lunn.ch Date: Tue, 27 Feb 2018 01:56:06 +0100 Subject: net: phy: Restore phy_resume() locking assumption

From: Andrew Lunn andrew@lunn.ch

commit 9c2c2e62df3fa30fb13fbeb7512a4eede729383b upstream.

commit f5e64032a799 ("net: phy: fix resume handling") changes the locking semantics for phy_resume() such that the caller now needs to hold the phy mutex. Not all call sites were adopted to this new semantic, resulting in warnings from the added WARN_ON(!mutex_is_locked(&phydev->lock)). Rather than change the semantics, add a __phy_resume() and restore the old behavior of phy_resume().

Reported-by: Heiner Kallweit hkallweit1@gmail.com Fixes: f5e64032a799 ("net: phy: fix resume handling") Signed-off-by: Andrew Lunn andrew@lunn.ch Reviewed-by: Florian Fainelli f.fainelli@gmail.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org

--- drivers/net/phy/phy.c | 2 +- drivers/net/phy/phy_device.c | 18 +++++++++++++----- include/linux/phy.h | 1 + 3 files changed, 15 insertions(+), 6 deletions(-)

--- a/drivers/net/phy/phy.c +++ b/drivers/net/phy/phy.c @@ -841,7 +841,7 @@ void phy_start(struct phy_device *phydev break; case PHY_HALTED: /* if phy was suspended, bring the physical link up again */ - phy_resume(phydev); + __phy_resume(phydev);

/* make sure interrupts are re-enabled for the PHY */ if (phy_interrupt_is_valid(phydev)) { --- a/drivers/net/phy/phy_device.c +++ b/drivers/net/phy/phy_device.c @@ -135,9 +135,7 @@ static int mdio_bus_phy_resume(struct de if (!mdio_bus_phy_may_suspend(phydev)) goto no_resume;

- mutex_lock(&phydev->lock); ret = phy_resume(phydev); - mutex_unlock(&phydev->lock); if (ret < 0) return ret;

@@ -1028,9 +1026,7 @@ int phy_attach_direct(struct net_device if (err) goto error;

- mutex_lock(&phydev->lock); phy_resume(phydev); - mutex_unlock(&phydev->lock); phy_led_triggers_register(phydev);

return err; @@ -1156,7 +1152,7 @@ int phy_suspend(struct phy_device *phyde } EXPORT_SYMBOL(phy_suspend);

-int phy_resume(struct phy_device *phydev) +int __phy_resume(struct phy_device *phydev) { struct phy_driver *phydrv = to_phy_driver(phydev->mdio.dev.driver); int ret = 0; @@ -1173,6 +1169,18 @@ int phy_resume(struct phy_device *phydev

return ret; } +EXPORT_SYMBOL(__phy_resume); + +int phy_resume(struct phy_device *phydev) +{ + int ret; + + mutex_lock(&phydev->lock); + ret = __phy_resume(phydev); + mutex_unlock(&phydev->lock); + + return ret; +} EXPORT_SYMBOL(phy_resume);

int phy_loopback(struct phy_device *phydev, bool enable) --- a/include/linux/phy.h +++ b/include/linux/phy.h @@ -817,6 +817,7 @@ void phy_device_remove(struct phy_device int phy_init_hw(struct phy_device *phydev); int phy_suspend(struct phy_device *phydev); int phy_resume(struct phy_device *phydev); +int __phy_resume(struct phy_device *phydev); int phy_loopback(struct phy_device *phydev, bool enable); struct phy_device *phy_attach(struct net_device *dev, const char *bus_id, phy_interface_t interface);

Patches currently in stable-queue which might be from andrew@lunn.ch are

queue-4.14/net-phy-fix-resume-handling.patch queue-4.14/net-phy-restore-phy_resume-locking-assumption.patch