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Date: Fri, 2 Feb 2024 20:26:36 -0800
From: Stephen Hemminger <stephen@networkplumber.org>
To: Andrew Boyer <andrew.boyer@amd.com>
Cc: <dev@dpdk.org>, Neel Patel <neel.patel@amd.com>, <stable@dpdk.org>
Subject: Re: [PATCH 04/13] net/ionic: fix missing volatile type for cqe
 pointers
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In-Reply-To: <20240202193238.62669-5-andrew.boyer@amd.com>
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On Fri, 2 Feb 2024 11:32:29 -0800
Andrew Boyer <andrew.boyer@amd.com> wrote:

> From: Neel Patel <neel.patel@amd.com>
> 
> This memory may be changed by the hardware, so the volatile
> keyword is required for correctness.
> 
> Fixes: e86a6fcc7cf3 ("net/ionic: add optimized non-scattered Rx/Tx")
> cc: stable@dpdk.org
> 
> Signed-off-by: Andrew Boyer <andrew.boyer@amd.com>
> Signed-off-by: Neel Patel <neel.patel@amd.com>

In general barriers are better than volatile.
Volatile is a compiler not hardware construct really.

https://www.kernel.org/doc/html/latest/process/volatile-considered-harmful.html