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Date:   Wed, 17 Mar 2021 11:40:59 -0700
From:   Jakub Kicinski <kuba@kernel.org>
To:     Bhaskar Upadhaya <bupadhaya@marvell.com>
Cc:     "netdev@vger.kernel.org" <netdev@vger.kernel.org>,
        Ariel Elior <aelior@marvell.com>,
        Igor Russkikh <irusskikh@marvell.com>,
        "davem@davemloft.net" <davem@davemloft.net>
Subject: Re: [EXT] Re: [PATCH net 1/2] qede: fix to disable start_xmit
 functionality during self adapter test
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On Wed, 17 Mar 2021 06:33:37 +0000 Bhaskar Upadhaya wrote:
> > But an interrupt can come in after and enable Tx again.
> > I think you should keep the qede_netif_stop() here instead of moving it
> > down, no?  
> 
> Hi Jakub,
> Normal Traffic flow is enabled by qede_netif_start(edev) and which is placed at the end of this qede_selftest_run_loopback()
> qede_netif_stop(edev) is called prior to the call to qede_netif_start(edev), so unless qede_netif_start(edev)  is called Normal traffic flow will not
> be operational. 

I'm not talking about submitting more traffic.

Consider the following order of events

normal traffic		test

xmit()
			netif_tx_disable()
IRQ
NAPI
netif_tx_wake_queue()

     <--- traffic running again --->

			qede_netif_stop()