From 5f9c840107cfb172dae8704a05b966856af45811 Mon Sep 17 00:00:00 2001
From: Jeremy Linton <jeremy.linton@arm.com>
Date: Tue, 6 Mar 2018 09:00:06 -0600
Subject: [PATCH] net: smsc911x: Fix unload crash when link is up
Patch-mainline: v4.16-rc7
Git-commit: e06513d78d54e6c7026c9043a39e2c01ee25bdbe
References: git-fixes
The smsc911x driver will crash if it is rmmod'ed while the netdev
is up like:
Call trace:
phy_detach+0x94/0x150
phy_disconnect+0x40/0x50
smsc911x_stop+0x104/0x128 [smsc911x]
__dev_close_many+0xb4/0x138
dev_close_many+0xbc/0x190
rollback_registered_many+0x140/0x460
rollback_registered+0x68/0xb0
unregister_netdevice_queue+0x100/0x118
unregister_netdev+0x28/0x38
smsc911x_drv_remove+0x58/0x130 [smsc911x]
platform_drv_remove+0x30/0x50
device_release_driver_internal+0x15c/0x1f8
driver_detach+0x54/0x98
bus_remove_driver+0x64/0xe8
driver_unregister+0x34/0x60
platform_driver_unregister+0x20/0x30
smsc911x_cleanup_module+0x14/0xbca8 [smsc911x]
SyS_delete_module+0x1e8/0x238
__sys_trace_return+0x0/0x4
This is caused by the mdiobus being unregistered/free'd
and the code in phy_detach() attempting to manipulate mdio
related structures from unregister_netdev() calling close()
To fix this, we delay the mdiobus teardown until after
the netdev is deregistered.
Reported-by: Matt Sealey <matt.sealey@arm.com>
Signed-off-by: Jeremy Linton <jeremy.linton@arm.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Denis Kirjanov <denis.kirjanov@suse.com>
---
drivers/net/ethernet/smsc/smsc911x.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/net/ethernet/smsc/smsc911x.c b/drivers/net/ethernet/smsc/smsc911x.c
index ea1bbc355b4d..ea1c7c6c2631 100644
--- a/drivers/net/ethernet/smsc/smsc911x.c
+++ b/drivers/net/ethernet/smsc/smsc911x.c
@@ -2335,14 +2335,14 @@ static int smsc911x_drv_remove(struct platform_device *pdev)
pdata = netdev_priv(dev);
BUG_ON(!pdata);
BUG_ON(!pdata->ioaddr);
- WARN_ON(dev->phydev);
SMSC_TRACE(pdata, ifdown, "Stopping driver");
+ unregister_netdev(dev);
+
mdiobus_unregister(pdata->mii_bus);
mdiobus_free(pdata->mii_bus);
- unregister_netdev(dev);
res = platform_get_resource_byname(pdev, IORESOURCE_MEM,
"smsc911x-memory");
if (!res)
--
2.16.4