Re: [dpdk-users] [dpdk-dev] IGB_UIO: PCI Resources Management

[Ferruh Yigit <ferruh.yigit@intel.com>]

On 1/12/2017 12:12 PM, Alejandro Lucero wrote:
> 
> 
> On Thu, Jan 12, 2017 at 11:55 AM, Ferruh Yigit <ferruh.yigit@intel.com
> <mailto:ferruh.yigit@intel.com>> wrote:
> 
>     On 12/9/2016 8:54 AM, Gregory Etelson wrote:
>     > Hello,
>     >
>     > IGB_UIO driver does not close port PCI activities after DPDK process exits.
>     > DPDK API provides rte_eth_dev_close() to manage port PCI,
>     > but it can be skipped if process receives SIGKILL signal
> 
>     I guess I understand the problem.
> 
> 
> This is a known problem, but it is not just a UIO problem, and this
> patch does not solve it, maybe it just solves part of it.
> 
> In fact, a DPDK program crashing could imply the NIC DMAing after that
> and after that memory was assigned to another program.

Yes.
Can there be a way to stop NIC DMA, (or prevent it access to mem
anymore) when app crashes?
I think that is what this patch is looking for.

> 
>  
> 
> 
>     > The patches below provide IGB_UIO release callback and IXGBEVF release function
> 
>     But adding ixgbe specific code into igb_uio may not be good idea.
>     Can be anything done one upper layer, pci layer, generic to all drivers?
> 
> 
> This  module is not just being used for Intel cards, so this addition
> will break, at least, the NFP PMD support.
> 
> I was told to use igb_uio instead of adding a new NFP uio driver, so I
> guess that implies this igb_uio driver should be considered not only a
> igb driver.

No it is generic, I think names has igb_ just for historical reasons.

>  
> 
>     > With the patches, each time DPDK process terminates,
>     > UIO release callback will trigger port PCI close.
>     > On the down side, patched IGB_UIO can be bound to a single adapter type
>     >
>     > Regards,
>     > Gregory
> 
>     <...>
> 
>