[v2] net: ftgmac100: Fix crash when removing driver

Message ID 20201116032715.1011071-1-joel@jms.id.au
State New
Headers show
Series
  • [v2] net: ftgmac100: Fix crash when removing driver
Related show

Commit Message

Joel Stanley Nov. 16, 2020, 3:27 a.m.
When removing the driver we would hit BUG_ON(!list_empty(&dev->ptype_specific))
in net/core/dev.c due to still having the NC-SI packet handler
registered.

 # echo 1e660000.ethernet > /sys/bus/platform/drivers/ftgmac100/unbind
  ------------[ cut here ]------------
  kernel BUG at net/core/dev.c:10254!
  Internal error: Oops - BUG: 0 [#1] SMP ARM
  CPU: 0 PID: 115 Comm: sh Not tainted 5.10.0-rc3-next-20201111-00007-g02e0365710c4 #46
  Hardware name: Generic DT based system
  PC is at netdev_run_todo+0x314/0x394
  LR is at cpumask_next+0x20/0x24
  pc : [<806f5830>]    lr : [<80863cb0>]    psr: 80000153
  sp : 855bbd58  ip : 00000001  fp : 855bbdac
  r10: 80c03d00  r9 : 80c06228  r8 : 81158c54
  r7 : 00000000  r6 : 80c05dec  r5 : 80c05d18  r4 : 813b9280
  r3 : 813b9054  r2 : 8122c470  r1 : 00000002  r0 : 00000002
  Flags: Nzcv  IRQs on  FIQs off  Mode SVC_32  ISA ARM  Segment none
  Control: 00c5387d  Table: 85514008  DAC: 00000051
  Process sh (pid: 115, stack limit = 0x7cb5703d)
 ...
  Backtrace:
  [<806f551c>] (netdev_run_todo) from [<80707eec>] (rtnl_unlock+0x18/0x1c)
   r10:00000051 r9:854ed710 r8:81158c54 r7:80c76bb0 r6:81158c10 r5:8115b410
   r4:813b9000
  [<80707ed4>] (rtnl_unlock) from [<806f5db8>] (unregister_netdev+0x2c/0x30)
  [<806f5d8c>] (unregister_netdev) from [<805a8180>] (ftgmac100_remove+0x20/0xa8)
   r5:8115b410 r4:813b9000
  [<805a8160>] (ftgmac100_remove) from [<805355e4>] (platform_drv_remove+0x34/0x4c)

Fixes: bd466c3fb5a4 ("net/faraday: Support NCSI mode")
Signed-off-by: Joel Stanley <joel@jms.id.au>

---
v2: Also unregister in _probe

 drivers/net/ethernet/faraday/ftgmac100.c | 4 ++++
 1 file changed, 4 insertions(+)

-- 
2.29.2

Comments

Jakub Kicinski Nov. 17, 2020, 1:20 a.m. | #1
On Mon, 16 Nov 2020 13:57:15 +1030 Joel Stanley wrote:
> When removing the driver we would hit BUG_ON(!list_empty(&dev->ptype_specific))

> in net/core/dev.c due to still having the NC-SI packet handler

> registered.

> 

>  # echo 1e660000.ethernet > /sys/bus/platform/drivers/ftgmac100/unbind

>   ------------[ cut here ]------------

>   kernel BUG at net/core/dev.c:10254!

>   Internal error: Oops - BUG: 0 [#1] SMP ARM

>   CPU: 0 PID: 115 Comm: sh Not tainted 5.10.0-rc3-next-20201111-00007-g02e0365710c4 #46

>   Hardware name: Generic DT based system

>   PC is at netdev_run_todo+0x314/0x394

>   LR is at cpumask_next+0x20/0x24

>   pc : [<806f5830>]    lr : [<80863cb0>]    psr: 80000153

>   sp : 855bbd58  ip : 00000001  fp : 855bbdac

>   r10: 80c03d00  r9 : 80c06228  r8 : 81158c54

>   r7 : 00000000  r6 : 80c05dec  r5 : 80c05d18  r4 : 813b9280

>   r3 : 813b9054  r2 : 8122c470  r1 : 00000002  r0 : 00000002

>   Flags: Nzcv  IRQs on  FIQs off  Mode SVC_32  ISA ARM  Segment none

>   Control: 00c5387d  Table: 85514008  DAC: 00000051

>   Process sh (pid: 115, stack limit = 0x7cb5703d)

>  ...

>   Backtrace:

>   [<806f551c>] (netdev_run_todo) from [<80707eec>] (rtnl_unlock+0x18/0x1c)

>    r10:00000051 r9:854ed710 r8:81158c54 r7:80c76bb0 r6:81158c10 r5:8115b410

>    r4:813b9000

>   [<80707ed4>] (rtnl_unlock) from [<806f5db8>] (unregister_netdev+0x2c/0x30)

>   [<806f5d8c>] (unregister_netdev) from [<805a8180>] (ftgmac100_remove+0x20/0xa8)

>    r5:8115b410 r4:813b9000

>   [<805a8160>] (ftgmac100_remove) from [<805355e4>] (platform_drv_remove+0x34/0x4c)

> 

> Fixes: bd466c3fb5a4 ("net/faraday: Support NCSI mode")

> Signed-off-by: Joel Stanley <joel@jms.id.au>


> diff --git a/drivers/net/ethernet/faraday/ftgmac100.c b/drivers/net/ethernet/faraday/ftgmac100.c

> index 983b6db2d80d..88bfe2107938 100644

> --- a/drivers/net/ethernet/faraday/ftgmac100.c

> +++ b/drivers/net/ethernet/faraday/ftgmac100.c

> @@ -1926,6 +1926,8 @@ static int ftgmac100_probe(struct platform_device *pdev)

>  err_phy_connect:

>  	ftgmac100_phy_disconnect(netdev);


This line does not exist in net, only in net-next, please respin on top
of net so we can apply this to Linux 5.10 and backport to older stable
releases.
Jakub Kicinski Nov. 17, 2020, 1:21 a.m. | #2
On Mon, 16 Nov 2020 17:20:44 -0800 Jakub Kicinski wrote:
> On Mon, 16 Nov 2020 13:57:15 +1030 Joel Stanley wrote:

> > When removing the driver we would hit BUG_ON(!list_empty(&dev->ptype_specific))

> > in net/core/dev.c due to still having the NC-SI packet handler

> > registered.

> > 

> >  # echo 1e660000.ethernet > /sys/bus/platform/drivers/ftgmac100/unbind

> >   ------------[ cut here ]------------

> >   kernel BUG at net/core/dev.c:10254!

> >   Internal error: Oops - BUG: 0 [#1] SMP ARM

> >   CPU: 0 PID: 115 Comm: sh Not tainted 5.10.0-rc3-next-20201111-00007-g02e0365710c4 #46

> >   Hardware name: Generic DT based system

> >   PC is at netdev_run_todo+0x314/0x394

> >   LR is at cpumask_next+0x20/0x24

> >   pc : [<806f5830>]    lr : [<80863cb0>]    psr: 80000153

> >   sp : 855bbd58  ip : 00000001  fp : 855bbdac

> >   r10: 80c03d00  r9 : 80c06228  r8 : 81158c54

> >   r7 : 00000000  r6 : 80c05dec  r5 : 80c05d18  r4 : 813b9280

> >   r3 : 813b9054  r2 : 8122c470  r1 : 00000002  r0 : 00000002

> >   Flags: Nzcv  IRQs on  FIQs off  Mode SVC_32  ISA ARM  Segment none

> >   Control: 00c5387d  Table: 85514008  DAC: 00000051

> >   Process sh (pid: 115, stack limit = 0x7cb5703d)

> >  ...

> >   Backtrace:

> >   [<806f551c>] (netdev_run_todo) from [<80707eec>] (rtnl_unlock+0x18/0x1c)

> >    r10:00000051 r9:854ed710 r8:81158c54 r7:80c76bb0 r6:81158c10 r5:8115b410

> >    r4:813b9000

> >   [<80707ed4>] (rtnl_unlock) from [<806f5db8>] (unregister_netdev+0x2c/0x30)

> >   [<806f5d8c>] (unregister_netdev) from [<805a8180>] (ftgmac100_remove+0x20/0xa8)

> >    r5:8115b410 r4:813b9000

> >   [<805a8160>] (ftgmac100_remove) from [<805355e4>] (platform_drv_remove+0x34/0x4c)

> > 

> > Fixes: bd466c3fb5a4 ("net/faraday: Support NCSI mode")

> > Signed-off-by: Joel Stanley <joel@jms.id.au>  

> 

> > diff --git a/drivers/net/ethernet/faraday/ftgmac100.c b/drivers/net/ethernet/faraday/ftgmac100.c

> > index 983b6db2d80d..88bfe2107938 100644

> > --- a/drivers/net/ethernet/faraday/ftgmac100.c

> > +++ b/drivers/net/ethernet/faraday/ftgmac100.c

> > @@ -1926,6 +1926,8 @@ static int ftgmac100_probe(struct platform_device *pdev)

> >  err_phy_connect:

> >  	ftgmac100_phy_disconnect(netdev);  

> 

> This line does not exist in net, only in net-next, please respin on top

> of net so we can apply this to Linux 5.10 and backport to older stable

> releases.


Ah, and when you respin please put [PATCH net v3] in the subject so
that bots know which tree to test against.

Patch

diff --git a/drivers/net/ethernet/faraday/ftgmac100.c b/drivers/net/ethernet/faraday/ftgmac100.c
index 983b6db2d80d..88bfe2107938 100644
--- a/drivers/net/ethernet/faraday/ftgmac100.c
+++ b/drivers/net/ethernet/faraday/ftgmac100.c
@@ -1926,6 +1926,8 @@  static int ftgmac100_probe(struct platform_device *pdev)
 err_phy_connect:
 	ftgmac100_phy_disconnect(netdev);
 err_ncsi_dev:
+	if (priv->ndev)
+		ncsi_unregister_dev(priv->ndev);
 	ftgmac100_destroy_mdio(netdev);
 err_setup_mdio:
 	iounmap(priv->base);
@@ -1945,6 +1947,8 @@  static int ftgmac100_remove(struct platform_device *pdev)
 	netdev = platform_get_drvdata(pdev);
 	priv = netdev_priv(netdev);
 
+	if (priv->ndev)
+		ncsi_unregister_dev(priv->ndev);
 	unregister_netdev(netdev);
 
 	clk_disable_unprepare(priv->rclk);