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

From: Eric Dumazet <[email-masked]>
Date: Sun, 21 Jan 2018 08:43:18 -0800

On Sun, 2018-01-21 at 18:24 +0200, Tariq Toukan wrote:
> 
> On 21/01/2018 11:31 AM, Tariq Toukan 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?

Yeah, mlx4 NICs in Google fleet receive trillions of packets per
second, and we never noticed an issue.

Although we are using a slightly different driver, using order-0 pages
and fast pages recycling.