Re: [RFC/PATCH] Kdump: Disabling PCI interrupts in capture kernel

[Denis Vlasenko <vda@ilport.com.ua>]

On Friday 03 June 2005 21:36, Eric W. Biederman wrote:
> Greg KH <greg@kroah.com> writes:
> 
> > On Fri, Jun 03, 2005 at 04:55:24PM +0530, Vivek Goyal wrote:
> > > Hi,
> > > 
> > > In kdump, sometimes, general driver initialization issues seems to be cropping
> > 
> > > in second kernel due to devices not being shutdown during crash and these 
> > > devices are sending interrupts while second kernel is booting and drivers are
> > 
> > > not expecting any interrupts yet.
> > 
> > What are the errors you are seeing?
> > How would the drivers be able to be getting interrupts delivered to them
> > if they haven't registered the irq handler yet?
> 
> As I recall the drivers were not getting the interrupts but the interrupts
> were happening.  To stop being spammed the kernel disables the irq line,
> at the interrupt controller.  Then when the driver registered the
> interrupt it would never receive the interrupt.

Shouldn't kernel keep all interrupt lines initially disabled 
(sans platform-specific magic), and enable each like only when
a device driver requests IRQ? This sounds simpler to do...
--
vda