There is a race condition that can occur if EMAC interrupts are
enabled when phy_disconnect() is called.  phy_disconnect() sets
adjust_link to NULL.  When an interrupt occurs, the ISR might
call phy_mac_interrupt(), which wakes up the workqueue function
phy_state_machine().  This function might reference adjust_link,
thereby causing a null pointer exception.

Signed-off-by: Timur Tabi <>
 drivers/net/ethernet/qualcomm/emac/emac-mac.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/qualcomm/emac/emac-mac.c 
index e97968e..6fb3bee 100644
--- a/drivers/net/ethernet/qualcomm/emac/emac-mac.c
+++ b/drivers/net/ethernet/qualcomm/emac/emac-mac.c
@@ -1021,14 +1021,18 @@ void emac_mac_down(struct emac_adapter *adpt)
-       phy_disconnect(adpt->phydev);
-       /* disable mac irq */
+       /* Interrupts must be disabled before the PHY is disconnected, to
+        * avoid a race condition where adjust_link is null when we get
+        * an interrupt.
+        */
        writel(DIS_INT, adpt->base + EMAC_INT_STATUS);
        writel(0, adpt->base + EMAC_INT_MASK);
        free_irq(adpt->irq.irq, &adpt->irq);
+       phy_disconnect(adpt->phydev);
Qualcomm Datacenter Technologies, Inc. as an affiliate of Qualcomm
Technologies, Inc.  Qualcomm Technologies, Inc. is a member of the
Code Aurora Forum, a Linux Foundation Collaborative Project.

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