Received-SPF: softfail (google.com: domain of transitioning linux-kernel-owner@vger.kernel.org does not designate 23.128.96.19 as permitted sender) client-ip=23.128.96.19;
Date:   Fri, 18 Mar 2022 12:20:17 -0700
From:   Jakub Kicinski <kuba@kernel.org>
To:     Florian Fainelli <f.fainelli@gmail.com>
Cc:     Peter Robinson <pbrobinson@gmail.com>,
        Jeremy Linton <jeremy.linton@arm.com>, netdev@vger.kernel.org,
        opendmb@gmail.com, davem@davemloft.net,
        bcm-kernel-feedback-list@broadcom.com, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] net: bcmgenet: Use stronger register read/writes to
 assure ordering
Message-ID: <20220318122017.24341eb1@kicinski-fedora-pc1c0hjn.dhcp.thefacebook.com>
In-Reply-To: <472540d2-3a61-beca-70df-d5f152e1cfd1@gmail.com>
References: <20220310045358.224350-1-jeremy.linton@arm.com>
        <f831a4c6-58c9-20bd-94e8-e221369609e8@gmail.com>
        <de28c0ec-56a7-bfff-0c41-72aeef097ee3@arm.com>
        <2167202d-327c-f87d-bded-702b39ae49e1@gmail.com>
        <CALeDE9MerhZWwJrkg+2OEaQ=_9C6PHYv7kQ_XEQ6Kp7aV2R31A@mail.gmail.com>
        <472540d2-3a61-beca-70df-d5f152e1cfd1@gmail.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=US-ASCII
Content-Transfer-Encoding: 7bit
Precedence: bulk

On Fri, 18 Mar 2022 12:01:20 -0700 Florian Fainelli wrote:
> Given the time crunch we should go with Jeremy's patch that uses
> stronger I/O access method and then we will work with Jeremy offline to
> make sure that our version of GCC12 is exactly the same as his, as well
> as the compiler options (like -mtune/-march) to reproduce this.
> 
> If we believe this is only a problem with GCC12 and 5.17 in Fedora, then
> I would be inclined to remove the Fixes tag such that when we come up
> with a more localized solution we do not have to revert "net: bcmgenet:
> Use stronger register read/writes to assure ordering" from stable
> branches. This would be mostly a courtesy to our future selves, but an
> argument could be made that this probably has always existed, and that
> different compilers could behave more or less like GCC12.

Are you expecting this patch to make 5.17? If Linus cuts final this
weekend, as he most likely will, unless we do something special the
patch in question will end up getting merged during the merge window.
Without the Fixes tag you'll need to manually instruct Greg to pull 
it in. Is that the plan?