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Date: Wed, 29 Mar 2017 14:30:14 -0700 (PDT)
Message-Id: <20170329.143014.2001816338079751776.davem@davemloft.net>
To: Vladislav.Zakharov@synopsys.com
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Subject: Re: [PATCH] ezchip: nps_enet: check if napi has been completed
From: David Miller <davem@davemloft.net>
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From: Vlad Zakharov <Vladislav.Zakharov@synopsys.com>
Date: Wed, 29 Mar 2017 13:41:46 +0300

> After a new NAPI_STATE_MISSED state was added to NAPI we can get into
> this state and in such case we have to reschedule NAPI as some work is
> still pending and we have to process it. napi_complete_done() function
> returns false if we have to reschedule something (e.g. in case we were
> in MISSED state) as current polling have not been completed yet.
> 
> nps_enet driver hasn't been verifying the return value of
> napi_complete_done() and has been forcibly enabling interrupts. That is
> not correct as we should not enable interrupts before we have processed
> all scheduled work. As a result we were getting trapped in interrupt
> hanlder chain as we had never been able to disabale ethernet
> interrupts again.
> 
> So this patch makes nps_enet_poll() func verify return value of
> napi_complete_done() and enable interrupts only in case all scheduled
> work has been completed.
> 
> Signed-off-by: Vlad Zakharov <vzakhar@synopsys.com>

Applied.

Eric, if this is really required now, we have 148 broken drivers still.