Re: [PATCH v2 01/14] NTB: ntb_transport: Remove the device debugfs directory

[Logan Gunthorpe]

On 2026-09-09 22:08, Koichiro Den wrote:
> ntb_transport_free() removes QP debugfs directories but leaves the
> device directory. On rebind, debugfs_create_dir() fails with -EEXIST
> and QP statistics files are not recreated. Module unload masks this
> by removing the entire debugfs tree.
> 
> To reproduce:
> 
>   # ls /sys/kernel/debug/ntb_transport/0001:10:00.0/
>   qp0
>   # echo 0001:10:00.0 > /sys/bus/ntb/drivers/ntb_transport/unbind
>   # ls /sys/kernel/debug/ntb_transport/
>   0001:10:00.0   <-- should not remain
>   # echo 0001:10:00.0 > /sys/bus/ntb/drivers/ntb_transport/bind
> 
>   .. and then dmesg shows:
>   debugfs: '0001:10:00.0' already exists in 'ntb_transport'
> 
>   # ls /sys/kernel/debug/ntb_transport/0001:10:00.0/
>   (nothing)      <-- should be 'qp0'
> 
> Remove the device debugfs tree on teardown and probe failure.
> 
> Verified that unbind removes the directory and rebind recreates qp0.
> 
> Fixes: c8650fd03d32 ("NTB: Fix transport stats for multiple devices")
> Cc: stable@xxxxxxxxxxxxxxx
> Signed-off-by: Koichiro Den <den@xxxxxxxxxxxxx>

Looks good to me:

Reviewed-by: Logan Gunthorpe <logang@xxxxxxxxxxxx>