| Message ID | 20201117024448.1170761-1-joel@jms.id.au (mailing list archive) |
|---|---|
| State | Accepted |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | [net,v3] net: ftgmac100: Fix crash when removing driver | expand |
| Context | Check | Description |
|---|---|---|
| netdev/cover_letter | success | Link |
| netdev/fixes_present | success | Link |
| netdev/patch_count | success | Link |
| netdev/tree_selection | success | Clearly marked for net |
| netdev/subject_prefix | success | Link |
| netdev/source_inline | success | Was 0 now: 0 |
| netdev/verify_signedoff | success | Link |
| netdev/module_param | success | Was 0 now: 0 |
| netdev/build_32bit | success | Errors and warnings before: 0 this patch: 0 |
| netdev/kdoc | success | Errors and warnings before: 0 this patch: 0 |
| netdev/verify_fixes | success | Link |
| netdev/checkpatch | success | total: 0 errors, 0 warnings, 0 checks, 16 lines checked |
| netdev/build_allmodconfig_warn | success | Errors and warnings before: 0 this patch: 0 |
| netdev/header_inline | success | Link |
| netdev/stable | success | Stable not CCed |
On Tue, 17 Nov 2020 13:14:48 +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> Applied, thanks! There's at least one more bug here - at least two goto err_ncsi_dev don't set err, so the function will return 0 even tho there was an error.
diff --git a/drivers/net/ethernet/faraday/ftgmac100.c b/drivers/net/ethernet/faraday/ftgmac100.c index 00024dd41147..80fb1f537bb3 100644 --- a/drivers/net/ethernet/faraday/ftgmac100.c +++ b/drivers/net/ethernet/faraday/ftgmac100.c @@ -1907,6 +1907,8 @@ static int ftgmac100_probe(struct platform_device *pdev) clk_disable_unprepare(priv->rclk); clk_disable_unprepare(priv->clk); err_ncsi_dev: + if (priv->ndev) + ncsi_unregister_dev(priv->ndev); ftgmac100_destroy_mdio(netdev); err_setup_mdio: iounmap(priv->base); @@ -1926,6 +1928,8 @@ 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);
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> --- v3: Apply to net so it can go in as a fix v2: Also unregister in _probe --- drivers/net/ethernet/faraday/ftgmac100.c | 4 ++++ 1 file changed, 4 insertions(+)