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Message-ID: <a0f3166c-b520-d3db-6131-fb29809463a9@linux.intel.com>
Date:   Tue, 4 Jul 2023 08:28:56 +0300
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Subject: Re: [Intel-wired-lan] [PATCH net v2 3/6] igc: Handle already enabled
 taprio offload for basetime 0
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To:     Florian Kauer <florian.kauer@linutronix.de>,
        Jesse Brandeburg <jesse.brandeburg@intel.com>,
        Tony Nguyen <anthony.l.nguyen@intel.com>,
        Vinicius Costa Gomes <vinicius.gomes@intel.com>,
        "David S . Miller" <davem@davemloft.net>,
        Eric Dumazet <edumazet@google.com>,
        Jakub Kicinski <kuba@kernel.org>,
        Paolo Abeni <pabeni@redhat.com>,
        Tan Tee Min <tee.min.tan@linux.intel.com>,
        Muhammad Husaini Zulkifli <muhammad.husaini.zulkifli@intel.com>,
        Aravindhan Gunasekaran <aravindhan.gunasekaran@intel.com>,
        Malli C <mallikarjuna.chilakala@intel.com>
Cc:     netdev@vger.kernel.org, kurt@linutronix.de,
        intel-wired-lan@lists.osuosl.org, linux-kernel@vger.kernel.org
References: <20230619100858.116286-1-florian.kauer@linutronix.de>
 <20230619100858.116286-4-florian.kauer@linutronix.de>
From:   "naamax.meir" <naamax.meir@linux.intel.com>
In-Reply-To: <20230619100858.116286-4-florian.kauer@linutronix.de>
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On 6/19/2023 13:08, Florian Kauer wrote:
> Since commit e17090eb2494 ("igc: allow BaseTime 0 enrollment for Qbv")
> it is possible to enable taprio offload with a basetime of 0.
> However, the check if taprio offload is already enabled for i225
> (and thus -EALREADY should be returned for igc_save_qbv_schedule)
> still relied on adapter->base_time > 0.
> 
> This can be reproduced as follows:
> 
>      # TAPRIO offload (flags == 0x2) and base-time = 0
>      sudo tc qdisc replace dev enp1s0 parent root handle 100 stab overhead 24 taprio \
> 	    num_tc 1 \
> 	    map 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 \
> 	    queues 1@0 \
> 	    base-time 0 \
> 	    sched-entry S 01 300000 \
> 	    flags 0x2
> 
>      # The second call should fail with "Error: Device failed to setup taprio offload."
>      # But that only happens if base-time was != 0
>      sudo tc qdisc replace dev enp1s0 parent root handle 100 stab overhead 24 taprio \
> 	    num_tc 1 \
> 	    map 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 \
> 	    queues 1@0 \
> 	    base-time 0 \
> 	    sched-entry S 01 300000 \
> 	    flags 0x2
> 
> Fixes: e17090eb2494 ("igc: allow BaseTime 0 enrollment for Qbv")
> Signed-off-by: Florian Kauer <florian.kauer@linutronix.de>
> Reviewed-by: Kurt Kanzenbach <kurt@linutronix.de>
> ---
>   drivers/net/ethernet/intel/igc/igc_main.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)

Tested-by: Naama Meir <naamax.meir@linux.intel.com>