RE: acpi interrupt storm when disabling, IPI hang

From: Nate Lawson [mailto:nate_at_root.org]
> Don Bowman wrote:
> > When i run 'acpiconf -d', i get an interrupt storm on irq9...
> > vmstat -i shows ~1000/s.
> > 
> > Jun 15 13:41:33 cdata kernel: Interrupt storm detected on 
> "irq9: acpi0";
> > throttling interrupt source
> > 
> > when i try to re-enable, i get an error:
> > 
> > # acpiconf -e
> > acpi0: interrupt handler already installed
> >     ACPI-0210: *** Error: Unable to install System Control Interrupt
> > Handler, AE_ALREADY_EXISTS
> > acpiconf: enable failed: Device not configured
> > # 
> > 
> > System is a Supermicro X5DPE motherboard, dual 2.8GHz Xeon,
> > 533MHz FSB, Intel e7501 chipset.
> 
> Some systems don't support legacy mode (acpi disabled).  
> Others support 
> legacy mode but don't support transition back to it after 
> acpi has been 
> enabled.
> 
> In this case, it's likely the flags aren't set right for 
> AcpiEnableSubsystem.  I'll look into it.
> 
> > The system will not boot 5.x if acpi is disabled.
> > It will run 4.x without trouble tho.
> 
> What do you mean by "will not boot"?  Hangs?  Panics?  More 
> info is needed.

It hangs during allocating PnP ISA I think. I have someone
who is looking into it now, a device ends up requesting -1 bytes.
He will post more info this week.