References: <20230314123759.132521-1-jh@henneberg-systemdesign.com>
 <20230314123759.132521-2-jh@henneberg-systemdesign.com>
 <ZBCIM//XkpFkiC4W@nimitz>
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From:   Jochen Henneberg <jh@henneberg-systemdesign.com>
To:     Piotr Raczynski <piotr.raczynski@intel.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
Date:   Tue, 14 Mar 2023 16:01:11 +0100
In-reply-to: <ZBCIM//XkpFkiC4W@nimitz>
Message-ID: <878rfzgysa.fsf@henneberg-systemdesign.com>
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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.

>
> 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.

>
> 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
>> 


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