Re: [dpdk-dev] [PATCH v7 3/6] igb_uio: fix MSI-X IRQ assignment with new IRQ function

[Bruce Richardson <bruce.richardson@intel.com>]

On Mon, Sep 11, 2017 at 06:56:39PM +0100, Ferruh Yigit wrote:
> On 9/5/2017 1:04 PM, Markus Theil wrote:
> > The patch which introduced the usage of pci_alloc_irq_vectors
> > came after the patch which switched to non-threaded ISR (f0d1896fa1),
> > but did not use non-threaded ISR, if pci_alloc_irq_vectors
> > is used.
> > 
> > Fixes: 99bb58f3adc7 ("igb_uio: switch to new irq function for
> > MSI-X")
> > Cc: nicolas.dichtel@6wind.com
> > 
> > Signed-off-by: Markus Theil <markus.theil@tu-ilmenau.de>
> > ---
> >  lib/librte_eal/linuxapp/igb_uio/igb_uio.c | 1 +
> >  1 file changed, 1 insertion(+)
> > 
> > diff --git a/lib/librte_eal/linuxapp/igb_uio/igb_uio.c b/lib/librte_eal/linuxapp/igb_uio/igb_uio.c
> > index 93bb71d..6885e72 100644
> > --- a/lib/librte_eal/linuxapp/igb_uio/igb_uio.c
> > +++ b/lib/librte_eal/linuxapp/igb_uio/igb_uio.c
> > @@ -331,6 +331,7 @@ igbuio_pci_enable_interrupts(struct rte_uio_pci_dev *udev)
> >  #else
> >  		if (pci_alloc_irq_vectors(udev->pdev, 1, 1, PCI_IRQ_MSIX) == 1) {
> >  			dev_dbg(&udev->pdev->dev, "using MSI-X");
> > +			udev->info.irq_flags = IRQF_NO_THREAD;
> 
> IRQF_NO_THREAD seems has been introduced in 2.6.39, so using this flag
> causing build error for kernel versions < 2.6.39.
> 
> btw, the flag is already in use, so issue is not related to this patch.
> 
> In DPDK documentation supported Linux kernel version is >= 2.6.34 [1].
> 
> We should either increase supported version to 2.6.39, or update igb_uio
> code.
> 
> I am for increasing minimum supported kernel version to 2.6.39, any
> objection / comment?
> 
> 2.6.39 released on May 2011
> 2.6.34 released on May 2010
> 

Only thing I can think of here is:
* is the necessary support for this in RHEL 6.x series
* anyone still care about RHEL 6 support?

/Bruce