Re: 2.6.21-rc3-git4 ata1.00: qc timeout (cmd 0xef) (crashdump kernel)

[Stephen Hemminger <shemminger@linux-foundation.org>]

On Tue, 13 Mar 2007 04:03:00 +0900
Tejun Heo <htejun@gmail.com> wrote:

> Stephen Hemminger wrote:
> >> 1. the controller has IRQ stuck high (infrequent but possible)
> >> 2. the IRQ is already requested by another device
> >> 3. the IRQ gets disabled due to screaming interrupts at the moment
> >> ata_piix does pci_enable_device().
> >>
> >> I think we can be much more resilient to screaming interrupts if we
> >> enable device with IRQ disabled and enable it after the device is
> >> initialized to some level, possibly when requesting IRQ.
> > 
> > The first thing the skge driver does is do a chip reset, and that should
> > cause IRQ to be disabled and cleared. The driver has no chance to
> > fix it if the BIOS left the IRQ screaming...
> 
> What if we do something like...
> 
> 	pci_intx(pdev, 0);
> 	pci_enable_device(pdev);
> 	/* initialize */
> 	request_irq(blah blah...);
> 	pci_intx(pdev, 1);
> 
> Would this work for skge?
> 

Okay for testing, but any change like this should be done in the base
PCI layer, not one off in a particular driver.

-- 
Stephen Hemminger <shemminger@linux-foundation.org>