Date:   Fri, 17 Mar 2023 13:32:24 +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 V2 2/2] net: stmmac: Premature loop termination check
 was ignored on ZC rx
Message-ID: <ZBRd2HyZdz52eXyz@nimitz>
References: <20230316075940.695583-1-jh@henneberg-systemdesign.com>
 <20230316075940.695583-3-jh@henneberg-systemdesign.com>
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On Thu, Mar 16, 2023 at 08:59:40AM +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")
> 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 ea51c7c93101..4886668a54c5 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];
> -- 
> 2.39.2
> 
LGTM, thanks.
Reviewed-by: Piotr Raczynski <piotr.raczynski@intel.com>