Re: [PATCH] usb: chipidea: udc: assign interrupt number to USB gadget structure

On Fri, Jun 04, 2021 at 11:34:53AM +0000, Jun Li wrote:

quoted

-----Original Message-----
From: Jun Li
Sent: Friday, June 4, 2021 7:10 PM
To: Greg KH <gregkh@linuxfoundation.org>
Cc: peter.chen@kernel.org; linux-usb@vger.kernel.org; dl-linux-imx
[off-list ref]; Faqiang Zhu [off-list ref]
Subject: RE: [PATCH] usb: chipidea: udc: assign interrupt number to USB gadget
structure

quoted

-----Original Message-----
From: Greg KH <gregkh@linuxfoundation.org>
Sent: Friday, June 4, 2021 6:52 PM
To: Jun Li <redacted>
Cc: peter.chen@kernel.org; linux-usb@vger.kernel.org; dl-linux-imx
[off-list ref]; Faqiang Zhu [off-list ref]
Subject: Re: [PATCH] usb: chipidea: udc: assign interrupt number to
USB gadget structure

On Fri, May 14, 2021 at 06:59:44PM +0800, Li Jun wrote:

quoted

Chipidea also need sync interrupt before unbind the udc while gadget
remove driver, otherwise setup irq handling may happen while unbind,
see below dump generated from android function switch stress test:

...

quoted

quoted

What commit does this fix?  Should it go to stable kernels, and if so,
how far back?

I will resend the patch with fix tag added.

Hi Greg,

I assume this problem may exist all along or very far, but this patch
need base one commit[1] to fix this problem, so I think that commit is
the point to know how far this patch can apply back for stable kernels,
in this case, please let me know if adding fix tag pointing to that commit
still the right way for this.

[1] 3c73bc52195d ("usb: gadget: core: sync interrupt before unbind the udc")

Yes, that's fine and the correct way to do it.

thanks,

greg k-h