Re: [dpdk-dev] [PATCH] igb_uio: fix build for longterm kernel 2.6.32.63

[Jincheng Miao <jmiao@redhat.com>]

This patch will make RHEL6 build failed.

The root cause is that RHEL-based kernel is slightly different with 
upstream kernel.
It has some functions (pci_num_vf, kstrtoul, etc) which don't exist in 
upstream
longterm kernel.

For better compatibility, IMHO it is distinguishing RHEL-based kernel 
and upstream one.
Using macro like:
```
#if LINUX_VERSION_CODE < KERNEL_VERSION(2, 6, 34) && \
     !(defined(RHEL_RELEASE_CODE) && RHEL_RELEASE_CODE >= 
RHEL_RELEASE_VERSION(6, 3))

static int pci_num_vf(struct pci_dev *dev)
  {
```

But this is RHEL-specified fix. For other distros, if they have some 
problem, we should
hack it in the same way.

Thanks and regards,
Jincheng Miao


On 10/30/2014 04:18 PM, Jincheng Miao wrote:
> There is a logical error in igb_uio/compat.h when define pci_num_vf().
> Only CONFIG_PCI_IOV enabled, this function could be defined.
>
> This patch fix the following error for linux-2.6.32.63:
> CC [M]  /root/dpdk-source/build/build/lib/librte_eal/linuxapp/igb_uio/igb_uio.o
> /root/dpdk-source/build/build/lib/librte_eal/linuxapp/igb_uio/igb_uio.c: In function ‘show_max_vfs’:
> /root/dpdk-source/build/build/lib/librte_eal/linuxapp/igb_uio/igb_uio.c:75: error: implicit declaration of function ‘pci_num_vf’
>
> Signed-off-by: Jincheng Miao <jmiao@redhat.com>
> ---
>   lib/librte_eal/linuxapp/igb_uio/compat.h |    2 +-
>   1 files changed, 1 insertions(+), 1 deletions(-)
>
> diff --git a/lib/librte_eal/linuxapp/igb_uio/compat.h b/lib/librte_eal/linuxapp/igb_uio/compat.h
> index 676fa1b..0af0cae 100644
> --- a/lib/librte_eal/linuxapp/igb_uio/compat.h
> +++ b/lib/librte_eal/linuxapp/igb_uio/compat.h
> @@ -21,7 +21,7 @@
>   #endif
>   
>   #if LINUX_VERSION_CODE < KERNEL_VERSION(2, 6, 34) && \
> -	!defined(CONFIG_PCI_IOV)
> +	defined(CONFIG_PCI_IOV)
>   
>   static int pci_num_vf(struct pci_dev *dev)
>   {