Re: console issue since 3.6, console=ttyS1 hangs

[Nathan]

On 10/29/2016 04:16 PM, Sean Young wrote:
> On Fri, Oct 28, 2016 at 02:42:25PM -0500, Nathan Zimmer wrote:
> > On Thu, Oct 27, 2016 at 09:19:16PM +0100, Sean Young wrote:
> > > On Wed, Oct 26, 2016 at 01:16:16PM -0500, Nathan Zimmer wrote:
> > > > On 10/25/2016 03:41 PM, Sean Young wrote:
> > > > > On Mon, Oct 24, 2016 at 04:49:25PM -0500, Nathan Zimmer wrote:
> > > > > > [    1.565062] serial8250: ttyS1 at I/O 0x2f8 (irq = 3) is a 16550A
> > > > > The isa probe driver find the serial port.
> > > > >
> > > > > > [    1.566453] serial 00:04: pnp_assign_resources, try dependent set 0
> > > > > > [    1.567383] serial 00:04:   couldn't assign io 0 (min 0x2f8 max 0x2f8)
> > > > > But then decides that the port is already in use (the existing serial driver).
> > > > > > [    1.568366] serial 00:04: pnp_assign_resources failed (-16)
> > > > > > [    1.569188] serial 00:04: unable to assign resources
> > > > > > [    1.569924] serial: probe of 00:04 failed with error -16
> > > > > Please try and boot 3.7.0 with "8250.share_irqs=1", maybe it will pick
> > > > > irq 3 and it will be happy again, but that is just a guess.
> > > > >
> > > > > I think I have not fully understood what the failure is. Does the serial
> > > > > port not work or does the boot hang? What are the symptoms?
> > > > With console=ttyS1 the boot will "hang", sometimes it makes it all the way
> > > > through but may take 30 minutes, instead of the 2-4 minutes this box
> > > Where does it hang? Any error messages?
> > Shortly after mounting the root.
> > After that I get no more output...
> >
> > Here is a failure log from 4.8.
> So does the console on the serial port work on 4.8? Also what does
> "cat /proc/interrupts" say with and without my change of ordering the
> serial pnp probe before the isa probe?
>
> It could be that the serial driver picking a different irq caused another
> driver to be forced to pick another irq which does not work.
>
>
> Sean

Works is a strong word.  It produces output until it hangs in boot.

It certainly could be another driver but I don't see another irq12 in 
the dmesg log.

I'll grab some data once I back in the office tomorrow.


Nate