System hangs at boot in xhci0

[Steven G. Kargl]

On Fri, Dec 09, 2016 at 11:58:21PM +0100, Hans Petter Selasky wrote:
> On 12/09/16 22:09, Steve Kargl wrote:
> > I updated my system to
> >
> > % svn info /usr/src
> > Revision: 309748
> >
> > Built a shiny new kernel, which hangs during boot.
> > There is no panic.  Using the dmesg from kernel.old/kernel,
> > the last few reported are
> >
> >
> > pci2: <ACPI PCI bus> on pcib2
> > xhci0: <XHCI (generic) USB 3.0 controller> mem 0xfe900000-0xfe900fff
> > irq 48 at device 0.0 on pci2
> > xhci0: 32 bytes context size, 64-bit DMA
> >
> > At this point, the system is completely unresponse and
> > needs to be power cycled.
> >
> 
> Hi,
> 
> What is the next message in the old kernel which is printed? There has 
> been zero changes in the XHCI driver recently.
> 
> Can you copy /boot/kernel.old to /boot/kernel.works
> 
> Then add this option to the GENERIC kernel config:
> 
> options VERBOSE_SYSINIT
> 
> What are the last few messages in dmesg when you boot with the above flag?
> 

With a boot_verbose of the new kernel I get the following output:

xhci0: 32 bytes context size, 64-bit DMA
xhci0: attempting to allocate 1 MSI vectors (4 supported)
msi: routing MSI IRQ 260 to local APIC 16 vector 55
xhci0: using IRQ 260 for MSI
xhci0: MSI enabled
usbus0 on xhci0
xhci0: usbpf: Attached
random: harvesting attach, 8 bytes (4 bits) from usbus0
random: harvesting attach, 8 bytes (4 bits) from xhci0
random: harvesting attach, 8 bytes (4 bits) from pci2
random: harvesting attach, 8 bytes (4 bits) from pcib2

and then the system locks up.  With the old kernel (circa
Oct 10th sources), next few lines from dmesg are 

pcib3: <ACPI PCI-PCI bridge> irq 54 at device 10.0 on pci0
pcib0: allocated type 4 (0xd000-0xdfff) for rid 1c of pcib3
pcib0: allocated type 3 (0xfe800000-0xfe8fffff) for rid 20 of pcib3
pcib3:   domain            0
pcib3:   secondary bus     3
pcib3:   subordinate bus   3
pcib3:   I/O decode        0xd000-0xdfff
pcib3:   memory decode     0xfe800000-0xfe8fffff
pci3: <ACPI PCI bus> on pcib3

I think that hang isn't caused by xhci, but rather is a 
victim on being the last successfully probed device.  In the last
weeks there have been a few commits (309588, 309400, and 308953)
that touched ACPI.  I'm currently reverting these changes to test
if one is causing the problem.

I did see that one of these revisions specific mentions the
ALASKA AMI bios, which I happen to have.  However, that commit
also mentions a skylake processor while I have an AMD FX-8350.

-- 
Steve
http://troutmask.apl.washington.edu/~kargl/
https://www.youtube.com/watch?v=6hwgPfCcpyQ