Re: [PATCH] net/mlx4_en: ensure rx_desc updating reaches HW before prod db updating

[jianchao.wang]

Hi Tariq

On 01/22/2018 10:12 AM, jianchao.wang wrote:
>>> On 19/01/2018 5:49 PM, Eric Dumazet wrote:
>>>> On Fri, 2018-01-19 at 23:16 +0800, jianchao.wang wrote:
>>>>> Hi Tariq
>>>>>
>>>>> Very sad that the crash was reproduced again after applied the patch.
>> Memory barriers vary for different Archs, can you please share more details regarding arch and repro steps?

> The hardware is HP ProLiant DL380 Gen9/ProLiant DL380 Gen9, BIOS P89 12/27/2015
> The xen is installed. The crash occurred in DOM0.
> Regarding to the repro steps, it is a customer's test which does heavy disk I/O over NFS storage without any guest.
> 

What is the finial suggestion on this ?
If use wmb there, is the performance pulled down ?

Thanks in advance
Jianchao