USB ports on Lenovo T400 do not work after a suspend/resume

[Ian Smith]

On Sun, 7 Jul 2013 03:26:24 -0700, Jeremy Chadwick wrote:
 > On Sun, Jul 07, 2013 at 03:51:12PM +1000, Ian Smith wrote:
 > > On Sun, 30 Jun 2013 15:02:57 -0700, Adrian Chadd wrote:
 > >  > On 30 June 2013 07:22, Ian Smith <smithi at nimnet.asn.au> wrote:
 > > [..]
 > >  > > Nothing of note that I can see, if that usb hub-to-bus remapping is
 > >  > > normal.  As you said, 'CPU0: local APIC error 0x40' looks maybe sus.
 > >  > > Maybe someone who knows might comment on that?
 > > 
 > > Does noone know what that signifies?  Maybe it's not relevant to this.
 > 
 > It's too vague to know.  The error comes from lapic_handle_error(),
 > which is a generic/small routine which pulls the local APIC error status
 > register.  (Note I'm saying APIC, not ACPI -- two different things)

Indeed; I've been familiar with PICs since c.'79.  Googling to check 
what the 'A' stood for I found this .. from '97 but usefully descriptive 
perhaps: http://people.freebsd.org/~fsmp/SMP/papers/apicsubsystem.txt

I also found this from March 2011 involving Mike Tancsa, you and jhb@ :)
http://freebsd.1045724.n5.nabble.com/CPU0-local-APIC-error-0x40-CPU1-local-APIC-error-0x40-td3961805.html

 > apic_vector.S sets this up/makes use of this function, and its done as
 > an interrupt handler.

Whether an (unserviced?) interrupt error is related to Adrian's symptom 
- apparent total failure of USB reinitialisation on resume, but only if 
no USB devices exist in the external slots - remains to be seen.  hps@ 
has just confirmed that it should work the same as on boot, but then 
this error was flagged on boot - perhaps it also manifests on resume?

 > I think this is one of those situations where you have to know *what* is
 > being set up/done at that moment in time for the error code to mean
 > something.  Maybe booting verbose would give more information as to what
 > was being done that lead up to the line.
 > 
 > I've CC'd John Baldwin who might have some ideas.

Thanks.  We have verbose dmesg already.  Thread starts (in -stable) at
http://lists.freebsd.org/pipermail/freebsd-stable/2013-June/073917.html
and amidst some wild goose chases, pointer to verbose dmesg etc is at
http://lists.freebsd.org/pipermail/freebsd-stable/2013-June/074018.html

cheers, Ian