Re: [dpdk-dev] [PATCH 1/2] igb_uio: fix compability on old kernel

[Thomas Monjalon <thomas.monjalon@6wind.com>]

Hi Stephen,

There are some reports about build errors with igb_uio.
This is critical for the release.
As your patches have introduced this problem, we'd like
to have your opinion.

For release 1.7.1, I've reverted MSI support.
We should try to fix it for next release.

2014-09-01 16:55, Guillaume Gaudonville:
> On 07/25/2014 07:36 PM, Stephen Hemminger wrote:
> > +#if LINUX_VERSION_CODE < KERNEL_VERSION(2, 6, 37)
> > +/* Compatability wrapper for new kernel API for IRQ */
> > +#define irq_data	irq_desc
> > +#define irq_get_irq_data(irq)	irq_to_desc(irq)
> > +#define irq_data_get_msi(data)	get_irq_desc_msi(data)
> > +#endif
> 
> irq_to_desc is not exported to modules before kernel 3.4 and commit 
> 3911ff30.
> On Red Hat 6.5 the module fails to load due to an unknow symbol error.
> I've seen another post saying that it also fails to insert on kernel 2.6.34.
> I guess it should not work either on debian squeeze (kernel 2.6.32),
> did you compile it in built-in?

Generally speaking, I think your patches would need more tests.
If you cannot properly test your patches, you could explain how you test it,
when submitting patch, so someone else could continue the test campaign.

> For now, I don't see how we could fix it, since it is not exported we 
> are not allowed to use it in a kernel module.
> Do you have a way to fix this issue?

Waiting for the fix, MSI support is reverted.

Thanks for your understanding
-- 
Thomas