Re: [PATCH] usb: dwc3: Fix debugfs creation flow

[Minas Harutyunyan <Minas.Harutyunyan@synopsys.com>]

Hi Greg,

On 6/17/2021 10:10 AM, Greg Kroah-Hartman wrote:
> On Wed, Jun 16, 2021 at 10:56:02PM -0700, Minas Harutyunyan wrote:
>> Creation EP's debugfs called earlier than debugfs folder for dwc3
>> device created. As result EP's debugfs are created in '/sys/kernel/debug'
>> instead of '/sys/kernel/debug/usb/dwc3.1.auto'.
>>
>> Moved dwc3_debugfs_init() function call before calling
>> dwc3_core_init_mode() to allow create dwc3 debugfs parent before
>> creating EP's debugfs's.
>>
>> Fixes: 8562d5bfc0fc ("USB: dwc3: remove debugfs root dentry storage")
>> Signed-off-by: Minas Harutyunyan <hminas@synopsys.com>
>> ---
>>   drivers/usb/dwc3/core.c | 3 ++-
>>   1 file changed, 2 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
>> index e0a8e796c158..ba74ad7f6995 100644
>> --- a/drivers/usb/dwc3/core.c
>> +++ b/drivers/usb/dwc3/core.c
>> @@ -1620,17 +1620,18 @@ static int dwc3_probe(struct platform_device *pdev)
>>   	}
>>   
>>   	dwc3_check_params(dwc);
>> +	dwc3_debugfs_init(dwc);
>>   
>>   	ret = dwc3_core_init_mode(dwc);
>>   	if (ret)
>>   		goto err5;
>>   
>> -	dwc3_debugfs_init(dwc);
>>   	pm_runtime_put(dev);
>>   
>>   	return 0;
>>   
>>   err5:
>> +	dwc3_debugfs_exit(dwc);
>>   	dwc3_event_buffers_cleanup(dwc);
>>   
>>   	usb_phy_shutdown(dwc->usb2_phy);
>>
>> base-commit: 1da8116eb0c5dfc05cfb89896239badb18c4daf3
> 
> I thought we fixed this already in usb-next and usb-linus, right?  Where
> are you seeing this problem happening?

I faced this issue on 5.13.0-rc6. Patch "USB: dwc3: remove debugfs root 
dentry storage" introduced this issue, because of debugfs_lookup() 
function. I don't see any fix in usb-next.

Thanks,
Minas

> 
> thanks,
> 
> greg k-h
>