[dpdk-stable] [PATCH 17.11] net/enic: do not overwrite admin Tx queue limit

[Yongseok Koh]

> On Aug 2, 2018, at 9:35 PM, Hyong Youb Kim <hyonkim at cisco.com> wrote:
> 
> [ backported from upstream commit 2a7e3d54659cd12d337ad816dcf202eec1af1367 ]
> 
> Currently, enic_alloc_wq (via rte_eth_tx_queue_setup) may overwrite
> the admin limit with a lower value. This is wrong as seen in the
> following sequence.
> 
> 1. UCS admin-set Tx queue limit (config.wq_desc_count) = 4096
> 2. Set up tx queue with 512 descriptors
>   The admin limit (config.wq_desc_count) becomes 512.
> 3. Stop ports and now set up Tx queue with 1024 descriptors.
>   This fails because 1024 is greater than the admin limit (512).
> 
> Do not modify the admin limit, and when queried, report the current
> number of descriptors instead of the admin limit. The rx queue setup
> (enic_alloc_rq) does not this problem.
> 
> Fixes: fefed3d1e62c ("enic: new driver")
> 
> Signed-off-by: Hyong Youb Kim <hyonkim at cisco.com>
> Reviewed-by: John Daley <johndale at cisco.com>
> ---

Applied to stable/17.11

Thanks,
Yongseok