Re: [RFC] Delay EHCI initialization until khubd is idle

[Greg KH <greg@xxxxxxxxx>]

On Tue, Sep 02, 2008 at 11:32:50AM -0400, Alan Stern wrote:
> Everybody:
> 
> Frans Pop has been bothered by the error messages that appear in the 
> system log when EHCI initialization interrupts the initialization of 
> devices attached to the companion controllers.
> 
> The patch below provides a way to prevent these messages from being
> generated, most of the time.  It forces EHCI initialization to wait
> until khubd is idle, which won't happen until all devices attached to a
> companion controller have been initialized and enumerated, though not
> necessarily probed.
> 
> Now this is cosmetic at best.  Devices will still suffer a short
> disconnection when EHCI starts up; the difference is that now the
> errors will affect the drivers bound to those devices rather than
> affecting khubd.  Since drivers tend to produce relatively few error
> messages when a disconnect occurs (unlike khubd which tends to complain
> a lot), the log remains cleaner.
> 
> In theory this might even be detrimental.  For example, it's possible
> that the delay might allow time for a USB flash drive to be mounted
> before it is disconnected, instead of being disconnected before
> usb-storage can bind to it.

Yeah, I would worry about this thing happening a lot, that's not good,
and can slow down the boot process even more.

If the messages are annoying people, can we just change them to
debugging levels instead?

thanks,

greg k-h
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