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 <Y/XbXwKYpy3+pTah@corigine.com>
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From:   Henneberg - Systemdesign <lists@henneberg-systemdesign.com>
To:     Simon Horman <simon.horman@corigine.com>
Cc:     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
Date:   Wed, 22 Feb 2023 16:49:55 +0100
In-reply-to: <Y/XbXwKYpy3+pTah@corigine.com>
Message-ID: <87lekp66ko.fsf@henneberg-systemdesign.com>
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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.

>> Signed-off-by: Jochen Henneberg <jh@henneberg-systemdesign.com>
>
> That aside, this looks good to me.
>
> Reviewed-by: Simon Horman <simon.horman@corigine.com>
>
>> ---
>> V2: Added fixes tags
>> V3: Fixed fixes tag format
>> 
>>  drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 4 ++--
>>  1 file changed, 2 insertions(+), 2 deletions(-)
>> 
>> diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
>> index 1a5b8dab5e9b..de98c009866a 100644
>> --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
>> +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
>> @@ -5031,10 +5031,10 @@ static int stmmac_rx_zc(struct stmmac_priv *priv, int limit, u32 queue)
>>  			len = 0;
>>  		}
>>  
>> +read_again:
>>  		if (count >= limit)
>>  			break;
>>  
>> -read_again:
>>  		buf1_len = 0;
>>  		entry = next_entry;
>>  		buf = &rx_q->buf_pool[entry];
>> @@ -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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