Re: [regression] USB power management failure to suspend / high CPU usage

[Greg KH <greg@kroah.com>]

On Wed, Jan 02, 2019 at 10:42:55AM -0500, Eric Blau wrote:
> On Sun, Dec 23, 2018 at 11:28 AM Greg KH <greg@kroah.com> wrote:
> >
> > On Sun, Dec 23, 2018 at 08:49:42AM -0500, Eric Blau wrote:
> > >
> > > The behavior exists in 4.19.8 and 4.19.11, the kernel versions I have
> > > upgraded to with Arch Linux, so the regression was introduced sometime
> > > between 4.19.4 and 4.19.8. Hibernate still works but when I resume
> > > from hibernate, there is a ksoftirqd and kworker thread/process
> > > together taking up 100% of one core. If I turn off auto power control
> > > for usb1 and usb2, the threads stop spinning. i.e.,
> > >
> > > echo 'on' > '/sys/bus/usb/devices/usb1/power/control
> > >
> > > Any suggestions as to where this regression was introduced and what
> > > can be done to fix it?
> >
> > Sorry, this is a known issue, will be fixed in the next 4.19 release
> > that should be out next week.
> >
> > If you are curious, it is fixed by commit 45f750c16cae ("xhci: Don't
> > prevent USB2 bus suspend in state check intended for USB3 only") in
> > Linus's tree.
> 
> Hi Greg,
> 
> I've upgraded to 4.20 and the same regression still exists. I know
> this is not a stable release currently, but 4.20 has 45f750c16cae
> merged as commit 93a86395b429:
> 
> commit 93a86395b429c3a68a0d029f584f39890c0801b2
> Merge: 45f750c16cae 28a86092b175
> Author:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> AuthorDate: Fri Dec 14 17:06:09 2018 +0100
> Commit:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> CommitDate: Fri Dec 14 17:06:09 2018 +0100
> 
>     Merge tag 'usb-serial-4.20-rc7' of
> https://git.kernel.org/pub/scm/linux/kernel/git/johan/usb-serial into
> usb-linus
> 
> 
> The same workaround is still effective, but I thought I'd let you know
> that I'm still experiencing the same issue. If there's anything else I
> can do to help track this down, please let me know.

Can you post the information that you are still having this issue on the
linux-usb@vger.kernel.org mailing list, along with any kernel logs that
you might have that shows this?  The developers there can help you out.

thanks,

greg k-h