Date:   Thu, 23 Feb 2023 13:55:40 +0100
From:   Simon Horman <simon.horman@corigine.com>
To:     Jochen Henneberg <jh@henneberg-systemdesign.com>
Cc:     Andrew Lunn <andrew@lunn.ch>,
        Giuseppe Cavallaro <peppe.cavallaro@st.com>,
        Alexandre Torgue <alexandre.torgue@foss.st.com>,
        Jose Abreu <joabreu@synopsys.com>,
        "David S. Miller" <davem@davemloft.net>,
        Eric Dumazet <edumazet@google.com>,
        Jakub Kicinski <kuba@kernel.org>,
        Paolo Abeni <pabeni@redhat.com>,
        Maxime Coquelin <mcoquelin.stm32@gmail.com>,
        Ong Boon Leong <boon.leong.ong@intel.com>,
        netdev@vger.kernel.org, linux-stm32@st-md-mailman.stormreply.com,
        linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH net V3] net: stmmac: Premature loop termination check was
 ignored
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On Thu, Feb 23, 2023 at 12:34:18PM +0100, Jochen Henneberg wrote:
> 
> Andrew Lunn <andrew@lunn.ch> writes:
> 
> > On Wed, Feb 22, 2023 at 04:49:55PM +0100, Henneberg - Systemdesign wrote:
> >> 
> >> Simon Horman <simon.horman@corigine.com> writes:
> >> 
> >> > On Wed, Feb 22, 2023 at 08:38:28AM +0100, Jochen Henneberg wrote:
> >> >> 
> >> >> The premature loop termination check makes sense only in case of the
> >> >> jump to read_again where the count may have been updated. But
> >> >> read_again did not include the check.
> >> >> 
> >> >> Fixes: bba2556efad6 ("net: stmmac: Enable RX via AF_XDP zero-copy")
> >> >
> >> > This commit was included in v5.13
> >> >
> >> >> Fixes: ec222003bd94 ("net: stmmac: Prepare to add Split Header support")
> >> >
> >> > While this one was included in v5.4
> >> >
> >> > It seems to me that each of the above commits correspond to one
> >> > of the two hunks below. I don't know if that means this
> >> > patch should be split in two to assist backporting.
> >> >
> >> 
> >> I was thinking about this already but the change was so trivial that I
> >> hesitated to split it into two commits. I wanted I will surely change
> >> this.
> >
> > The advantage of splitting is that it makes back porting easy. Both
> > parts are needed for 6.1 and 5.15. 5.10 only needs the fix for
> > ec222003bd94. It if does not easily apply to 5.10 it could get
> > dropped. By splitting it, the backporting probably happens fully
> > automated, no human involved.
> 
> Understood. Will do the split and send two new patches. I will not
> continue with version upcounting and not send a patch series but two
> completly independent patches.

There may be fuzz if the patches are not applied in order.
I'd suggest making a series.