Re: [PATCH net-next v2] ch9200: do return USB errors from control_write()

[Sergey Shtylyov]

On 9/19/26 4:21 AM, Jakub Kicinski wrote:
[...]

>>> There is a second point about the resulting contract.  On success
>>> usb_control_msg() returns the transferred length, so control_write() now
>>> returns a positive value (2 for these register writes) rather than 0:
>>>
>>>         err = usb_control_msg(dev->udev, ...);
>>>         if (err >= 0 && err < size)
>>>                 err = -EINVAL;
>>>
>>> Would the obvious caller-side follow-up "if (retval) return retval;" then
>>> treat every successful 2-byte register write as a failure?  Would it be
>>> better to normalize success to 0 in control_write(), or to check
>>> "retval < 0" in each caller and update the callers in the same patch so
>>> the errors being returned are actually acted upon?
>>    That's what the patch I linked to does...
> 
> Please fix the issues in one series or not at all.

   OK. Series against net-next, right?

> We have too many patches in flight these days to be chasing people's
> linked series. Too many LLM-happy "helpers".

   IMHO these 2 patches are not so heavily linked, that's why I posted
them separately... And no AI was involved, of course. :-)

> Please explain how you discovered the issue and how you tested the fix.

   As I noted in the description of the patch [1], the issue was reported
by the static analyzer. For the patch [2], I saw a problem with my own eyes.
   I don't have the hardware, so no testing; there was some hope that e.g.
Matthew Garret (the driver's original submitter) could be able to test but
his email bounced...

[1] https://lore.kernel.org/all/20260914202503.52920-1-s.shtylyov@xxxxxxxxxxxx/
[2] https://lore.kernel.org/all/20260915185805.38712-1-s.shtylyov@xxxxxxxxxxxx/

MBR, Sergey