[EXT] Re: [PATCH] usb: ehci-hcd: Add IAA handshake for removing async QH

[Marek Vasut]

On 3/9/21 4:18 AM, Ye Li wrote:
> Hi Marek,

Hi,

[...]

>>>
>>> +                     10 * 1000); /* 10ms timeout */
>>> +     if (ret < 0)
>>> +             printf("EHCI fail timeout STS_IAA set\n");
>> Shouldn't there be some abort ^ if ret < 0 ?
>> Also, add the return value into the printf, it is useful for
>> debugging.
> I don't think need to abort anything when ret < 0. The ret value is
> very simple in handshake, when ret < 0, it must be -1.
> Actually the codes refer the ehci_enable_async for the usage of
> handshake.

If the handshake timed out, that indicates a problem and that problem 
shouldn't be ignored, but rather propagated, no ? Maybe the entire ehci 
transfer should be aborted ?

[...]

>>>
>>> +             ehci_writel(&ctrl->hcor->or_usbsts, STS_IAA);
>>> +
>>> +     return ret;
>>> +}
>> Is this a bugfix for this release or is this for next release ?
>> We're in rc3 already, so I would suggest to be careful.
> It is ok to add the fix for next release. From our tests, the issue is
> not very easy to reproduce by just using usb read/write.  In
> SCT, generally we need to run about 1 hour to see the issue.

Can you add details on how to reproduce the issue into the commit 
message ? That would be highly helpful.