Re: Regression: USB is nfg after suspend/resume(RAM) cycle on Intel chipset

[Mark Lord <lkml@rtr.ca>]

Mark Lord wrote:
>..
> 7ed92f1a149dddc3cb537ccd7441e98adac12c3e USB: make the autosuspend 
> workqueue thread freezable
> ef7f6c7084b333c7524dcd297e0578d43733a2a2 USB: more autosuspend timer stuff
> 
> I yanked them both, as they appeared to be releated based on the titles.
> Reverting this pair of commits fixes the USB suspend/resume regression.

Okay, just to make it trivial,
I've narrowed it down to only this commit from Alan Stern:

7ed92f1a149dddc3cb537ccd7441e98adac12c3e USB: make the autosuspend workqueue thread freezable
> 
> From: Alan Stern <stern@rowland.harvard.edu>
> Date: Tue, 22 May 2007 13:38:39 +0000 (-0400)
> Subject: USB: make the autosuspend workqueue thread freezable
> 
> USB: make the autosuspend workqueue thread freezable
> 
> This patch (as881b) makes the ksuspend_usb_wq workqueue freezable.  We
> don't want a rogue workqueue thread running around, unexpectedly
> suspending or resuming USB devices in the middle of a system sleep
> transition.
> 
> This fixes Bugzilla #8498.
> 
> Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
> ---
> 
> diff --git a/drivers/usb/core/usb.c b/drivers/usb/core/usb.c
> index 18ddc5e..80627b6 100644
> --- a/drivers/usb/core/usb.c
> +++ b/drivers/usb/core/usb.c
> @@ -205,7 +205,11 @@ struct device_type usb_device_type = {
>  
>  static int ksuspend_usb_init(void)
>  {
> -	ksuspend_usb_wq = create_singlethread_workqueue("ksuspend_usbd");
> +	/* This workqueue is supposed to be both freezable and
> +	 * singlethreaded.  Its job doesn't justify running on more
> +	 * than one CPU.
> +	 */
> +	ksuspend_usb_wq = create_freezeable_workqueue("ksuspend_usbd");
>  	if (!ksuspend_usb_wq)
>  		return -ENOMEM;
>  	return 0;
>