Date:   Wed, 15 Mar 2023 09:59:01 +0100
From:   Piotr Raczynski <piotr.raczynski@intel.com>
To:     Jochen Henneberg <jh@henneberg-systemdesign.com>
CC:     <netdev@vger.kernel.org>,
        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>,
        <linux-stm32@st-md-mailman.stormreply.com>,
        <linux-arm-kernel@lists.infradead.org>,
        <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH net 1/2] net: stmmac: Premature loop termination check
 was ignored
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References: <20230314123759.132521-1-jh@henneberg-systemdesign.com>
 <20230314123759.132521-2-jh@henneberg-systemdesign.com>
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On Tue, Mar 14, 2023 at 04:01:11PM +0100, Jochen Henneberg wrote:
> 
> Piotr Raczynski <piotr.raczynski@intel.com> writes:
> 
> > On Tue, Mar 14, 2023 at 01:37:58PM +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.
> >
> > Your commit titles and messages seems identical in both patches, someone
> > may get confused, maybe you could change commit titles at least?
> >
> > Or since those are very related one liner fixes, maybe combine them into
> > one?
> 
> I was told to split them into a series because the fixes apply to
> different kernel versions.
> 
Makes sense, thanks. However I'd still at least modify title to show
which patch fixes zc path or anything to distinguish them beside commit
sha.
> >
> > Also a question, since you in generally goto backwards here, is it guarded from
> > an infinite loop (during some corner case scenario maybe)?
> 
> In theory I think this may happen, however, I would consider that to be
> a different patch since it addresses a different issue.
> 

Right, it just caught my attention, probably just make sense to check
it.
> >
> > Other than that looks fine, thanks.
> > Reviewed-by: Piotr Raczynski <piotr.raczynski@intel.com>
> >
> >> 
> >> Fixes: ec222003bd94 ("net: stmmac: Prepare to add Split Header support")
> >> Signed-off-by: Jochen Henneberg <jh@henneberg-systemdesign.com>
> >> ---
> >>  drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 2 +-
> >>  1 file changed, 1 insertion(+), 1 deletion(-)
> >> 
> >> diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
> >> index e4902a7bb61e..ea51c7c93101 100644
> >> --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
> >> +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
> >> @@ -5221,10 +5221,10 @@ static int stmmac_rx(struct stmmac_priv *priv, int limit, u32 queue)
> >>  			len = 0;
> >>  		}
> >>  
> >> +read_again:
> >>  		if (count >= limit)
> >>  			break;
> >>  
> >> -read_again:
> >>  		buf1_len = 0;
> >>  		buf2_len = 0;
> >>  		entry = next_entry;
> >> -- 
> >> 2.39.2
> >> 
> 
> 
> -- 
> Henneberg - Systemdesign
> Jochen Henneberg
> Loehnfeld 26
> 21423 Winsen (Luhe)
> --
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