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Date:   Wed, 2 Dec 2020 09:18:52 -0800
From:   Jakub Kicinski <kuba@kernel.org>
To:     Lukasz Stelmach <l.stelmach@samsung.com>
Cc:     Andrew Lunn <andrew@lunn.ch>, jim.cromie@gmail.com,
        Heiner Kallweit <hkallweit1@gmail.com>,
        "David S. Miller" <davem@davemloft.net>,
        Rob Herring <robh+dt@kernel.org>,
        Kukjin Kim <kgene@kernel.org>,
        Krzysztof Kozlowski <krzk@kernel.org>,
        Russell King <linux@armlinux.org.uk>, netdev@vger.kernel.org,
        devicetree@vger.kernel.org, linux-kernel@vger.kernel.org,
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        <b.zolnierkie@samsung.com>,
        Marek Szyprowski <m.szyprowski@samsung.com>
Subject: Re: [PATCH v7 3/3] net: ax88796c: ASIX AX88796C SPI Ethernet
 Adapter Driver
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On Wed, 02 Dec 2020 11:46:28 +0100 Lukasz Stelmach wrote:
> >> +	status = netif_rx(skb);  
> >
> > If I'm reading things right this is in process context, so netif_rx_ni()
> >  
> 
> Is it? The stack looks as follows
> 
>     ax88796c_skb_return()
>     ax88796c_rx_fixup()
>     ax88796c_receive()
>     ax88796c_process_isr()
>     ax88796c_work()
> 
> and ax88796c_work() is a scheduled in the system_wq.

Are you asking if work queue gets run in process context? It does.

> >> +	if (status != NET_RX_SUCCESS)
> >> +		netif_info(ax_local, rx_err, ndev,
> >> +			   "netif_rx status %d\n", status);  
> >
> > Again, it's inadvisable to put per packet prints without any rate
> > limiting in the data path.  
> 
> Even if limmited by the msglvl flag, which is off by default?

I'd err on the side of caution, but up to you.