Re: [dpdk-dev] [PATCH V2] doc: add known PHY link up issue for i40e

["Zhang, Qi Z" <qi.z.zhang@intel.com>]

> -----Original Message-----
> From: Guo, Jia
> Sent: Thursday, November 8, 2018 12:18 AM
> To: Xing, Beilei <beilei.xing@intel.com>; Kovacevic, Marko
> <marko.kovacevic@intel.com>; Mcnamara, John
> <john.mcnamara@intel.com>; Zhang, Qi Z <qi.z.zhang@intel.com>
> Cc: dev@dpdk.org; Guo, Jia <jia.guo@intel.com>; Zhang, Helin
> <helin.zhang@intel.com>; Wu, Jingjing <jingjing.wu@intel.com>
> Subject: [PATCH V2] doc: add known PHY link up issue for i40e
> 
> If bind i40e NICs with PMD and run application, after application quits, some
> kernel driver may not be able to set PHY to link up again by ``ifconfig`` after
> NICs be rebound to kernel driver.
> 
> Signed-off-by: Jeff Guo <jia.guo@intel.com>
> ---
> v2->v1:
> refine some typo and word.
> ---
>  doc/guides/rel_notes/known_issues.rst | 27
> +++++++++++++++++++++++++++
>  1 file changed, 27 insertions(+)
> 
> diff --git a/doc/guides/rel_notes/known_issues.rst
> b/doc/guides/rel_notes/known_issues.rst
> index 95e4ce6..f4e3519 100644
> --- a/doc/guides/rel_notes/known_issues.rst
> +++ b/doc/guides/rel_notes/known_issues.rst
> @@ -759,3 +759,30 @@ Netvsc driver and application restart
> 
>  **Driver/Module**:
>     ``uio_hv_generic`` module.
> +
> +
> +PHY link up failed when rebind i40e NICs to kernel driver
> +---------------------------------------------------------
> +
> +**Description**:
> +   If bind i40e NICs with PMD and run application, after application quits,
> some
> +   kernel driver may not be able to set PHY to link up again by ``ifconfig``
> +   after NICs be rebound to kernel driver.

Should we switch the content of "description" and "implication"?

> +
> +**Implication**:
> +   Before application quits, it will invokes the function ``i40e_dev_stop``,
> +   which will set PHY to link down. This is the situation that some kernel
> +   driver may not be able to handle link status correctly after it retakes
> +   control of the device. It is a known PHY link configure synchronous issue
> in
> +   i40e kernel driver. The fix has been addressed in 2.7.4 rc version. So if
> +   the i40e kernel driver is < 2.7.4 and before the fix be backported into
> the
> +   previous versions, it will encounter this issue.
> +
> +**Resolution/Workaround**:
> +   If it does not help by remove and reinsert i40e kernel driver, please
> reboot system.
> +
> +**Affected Environment/Platform**:
> +   All.
> +
> +**Driver/Module**:
> +   Poll Mode Driver (PMD).
> --
> 2.7.4