| From foo@baz Sun Aug 26 09:13:00 CEST 2018 |
| From: Shubhrajyoti Datta <shubhrajyoti.datta@xilinx.com> |
| Date: Tue, 24 Jul 2018 10:09:53 +0530 |
| Subject: net: axienet: Fix double deregister of mdio |
| |
| From: Shubhrajyoti Datta <shubhrajyoti.datta@xilinx.com> |
| |
| [ Upstream commit 03bc7cab7d7218088412a75e141696a89059ab00 ] |
| |
| If the registration fails then mdio_unregister is called. |
| However at unbind the unregister ia attempted again resulting |
| in the below crash |
| |
| [ 73.544038] kernel BUG at drivers/net/phy/mdio_bus.c:415! |
| [ 73.549362] Internal error: Oops - BUG: 0 [#1] SMP |
| [ 73.554127] Modules linked in: |
| [ 73.557168] CPU: 0 PID: 2249 Comm: sh Not tainted 4.14.0 #183 |
| [ 73.562895] Hardware name: xlnx,zynqmp (DT) |
| [ 73.567062] task: ffffffc879e41180 task.stack: ffffff800cbe0000 |
| [ 73.572973] PC is at mdiobus_unregister+0x84/0x88 |
| [ 73.577656] LR is at axienet_mdio_teardown+0x18/0x30 |
| [ 73.582601] pc : [<ffffff80085fa4cc>] lr : [<ffffff8008616858>] |
| pstate: 20000145 |
| [ 73.589981] sp : ffffff800cbe3c30 |
| [ 73.593277] x29: ffffff800cbe3c30 x28: ffffffc879e41180 |
| [ 73.598573] x27: ffffff8008a21000 x26: 0000000000000040 |
| [ 73.603868] x25: 0000000000000124 x24: ffffffc879efe920 |
| [ 73.609164] x23: 0000000000000060 x22: ffffffc879e02000 |
| [ 73.614459] x21: ffffffc879e02800 x20: ffffffc87b0b8870 |
| [ 73.619754] x19: ffffffc879e02800 x18: 000000000000025d |
| [ 73.625050] x17: 0000007f9a719ad0 x16: ffffff8008195bd8 |
| [ 73.630345] x15: 0000007f9a6b3d00 x14: 0000000000000010 |
| [ 73.635640] x13: 74656e7265687465 x12: 0000000000000030 |
| [ 73.640935] x11: 0000000000000030 x10: 0101010101010101 |
| [ 73.646231] x9 : 241f394f42533300 x8 : ffffffc8799f6e98 |
| [ 73.651526] x7 : ffffffc8799f6f18 x6 : ffffffc87b0ba318 |
| [ 73.656822] x5 : ffffffc87b0ba498 x4 : 0000000000000000 |
| [ 73.662117] x3 : 0000000000000000 x2 : 0000000000000008 |
| [ 73.667412] x1 : 0000000000000004 x0 : ffffffc8799f4000 |
| [ 73.672708] Process sh (pid: 2249, stack limit = 0xffffff800cbe0000) |
| |
| Fix the same by making the bus NULL on unregister. |
| |
| Signed-off-by: Shubhrajyoti Datta <shubhrajyoti.datta@xilinx.com> |
| Signed-off-by: David S. Miller <davem@davemloft.net> |
| Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| --- |
| drivers/net/ethernet/xilinx/xilinx_axienet_mdio.c | 1 + |
| 1 file changed, 1 insertion(+) |
| |
| --- a/drivers/net/ethernet/xilinx/xilinx_axienet_mdio.c |
| +++ b/drivers/net/ethernet/xilinx/xilinx_axienet_mdio.c |
| @@ -218,6 +218,7 @@ issue: |
| ret = of_mdiobus_register(bus, np1); |
| if (ret) { |
| mdiobus_free(bus); |
| + lp->mii_bus = NULL; |
| return ret; |
| } |
| return 0; |