[PATCH v1] usb: xhci: Check return value of wait for TRB_TRANSFER event

[Marek Vasut]

On 10/18/23 05:46, Minda Chen wrote:
> 
> 
> On 2023/10/18 10:35, Marek Vasut wrote:
>> On 10/18/23 03:22, Minda Chen wrote:
>>>
>>>
>>> On 2023/10/17 19:20, Marek Vasut wrote:
>>>> On 10/17/23 08:20, Minda Chen wrote:
>>>>> xhci_wait_for_event() waiting TRB_TRANSFER event may return
>>>>> NULL. Checking the return value to avoid crash.
>>>>>
>>>>> Signed-off-by: Minda Chen <minda.chen at starfivetech.com>
>>>>
>>>> How did you trigger this error ? Is there a reproducer ? Details please ...
>>>
>>> While Scanning a lenovo usb2.0 udisk， not 100 % reproduce
>>
>> Can you include Linux
>>
>> lsusb -vvv
>>
>> output for this device and include that information in the commit message ? (or the U-Boot info below, that works too, just please add it into the commit message, it is important for future reference).
>>
> OK， I will add lsusb -vvv Linux udisk message and crash dump info to commit message

Thank you

>>> This is log.
>>>
>>> StarFive # usb reset
>>> resetting USB...
>>> Bus xhci_pci: Register 5000420 NbrPorts 5
>>> Starting the controller
>>> USB XHCI 1.00
>>> scanning bus xhci_pci for devices... WARN halted endpoint, queueing URB anyway.
>>> Unexpected XHCI event TRB, skipping... (f77141f0 00000000 13000000 02008401)
>>> Unhandled exception: Load access fault
>>> EPC: 00000000f7f563c6 RA: 00000000f7f563c6 TVAL: 000000000000000c
>>> EPC: 000000004024a3c6 RA: 000000004024a3c6 reloc adjusted
>>
>> Where does the crash point to in code, can you disassemble the PC pointer ? (or maybe you can use scripts/decodecode I think)
>>
> OK， I will add EPC pointer disassemble  to commit message

This part probably doesn't need to be in the commit message. I'd like to 
know where the crash occurred in the code.