RE: [PATCH] extcon: Fixed extcon duplicate issue

From: MyungJoo Ham

Date: Mon Oct 13 2025 - 02:38:04 EST


>extcon_dev_ids may re-alloc to another while this device unregister not complete
>
>The right timing shows below:
>on extcon_dev_register: ida_alloc -> device_register
>on extcon_dev_unregister: device_unregister -> ida_free
>
>stack information when an error occurs:
>sysfs: cannot create duplicate filename '/class/extcon/extcon1'
>CPU: 7 PID: 222 Comm: init Not tainted 6.6.77-android15-8-g9fab1123989e-ab13366090-4k #1 bbfe3ef014a40c2f67534a3e01169790ce021aeb
>Hardware name: sun60iw2 (DT)
>Call trace:
> dump_backtrace+0xe8/0x108
> show_stack+0x18/0x28
> dump_stack_lvl+0x50/0x6c
> dump_stack+0x18/0x24
> sysfs_warn_dup+0x68/0x88
> sysfs_do_create_link_sd+0x94/0xdc
> sysfs_create_link+0x30/0x48
> device_add_class_symlinks+0xb4/0x12c
> device_add+0x1e0/0x48c
> device_register+0x20/0x34
> extcon_dev_register+0x3b8/0x5c4
> devm_extcon_dev_register+0x4c/0x94
>
>Signed-off-by: Michael Wu <michael@xxxxxxxxxxxxxxxxx>



Acked-by: MyungJoo Ham <myungjoo.ham@xxxxxxxxxxx>

Cheers,
MyungJoo