Re: 2.6.8.1-mm2 (nvidia breakage)

[Bjorn Helgaas <bjorn.helgaas@hp.com>]

On Thursday 19 August 2004 3:51 pm, Terence Ripperda wrote:
> the original bug report was during module load time, when we're
> probing our devices via the pci_driver's probe callback. this is well
> before we hook up interrupts or do anything in our closed source code.
> 
> I'm attaching a trimmed down version of our driver that pretty much
> only does this probe (complete source is included). I don't know if
> this will reproduce the original bug or not.

Thanks, this is enough to show the problem:

	nv_kern_probe(struct pci_dev *dev, ...)
	{
		...
		nv->interrupt_line = dev->irq;
		...
		if (pci_enable_device(dev) != 0)

The driver is looking at dev->irq before calling pci_enable_device().
But dev->irq is not necessarily initialized before pci_enable_device().

I'm not a PCI expert, but I'm not sure you should be looking at
all the other dev->resource[] stuff before pci_enable_device()
either.  Most of the "modern" drivers in the tree seem to do
pci_enable_device() very early in the probe() function, i.e., 
see tg3.c.