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Date:   Wed, 21 Nov 2018 16:58:04 -0800 (PST)
Message-Id: <20181121.165804.509539437154732563.davem@davemloft.net>
To:     vincentc@andestech.com
Cc:     gregkh@linuxfoundation.org, rdunlap@infradead.org,
        yuehaibing@huawei.com, netdev@vger.kernel.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH v2] net: faraday: ftmac100: remove
 netif_running(netdev) check before disabling interrupts
From:   David Miller <davem@davemloft.net>
In-Reply-To: <1542764291-11208-1-git-send-email-vincentc@andestech.com>
References: <1542764291-11208-1-git-send-email-vincentc@andestech.com>
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From: Vincent Chen <vincentc@andestech.com>
Date: Wed, 21 Nov 2018 09:38:11 +0800

> In the original ftmac100_interrupt(), the interrupts are only disabled when
> the condition "netif_running(netdev)" is true. However, this condition
> causes kerenl hang in the following case. When the user requests to
> disable the network device, kernel will clear the bit __LINK_STATE_START
> from the dev->state and then call the driver's ndo_stop function. Network
> device interrupts are not blocked during this process. If an interrupt
> occurs between clearing __LINK_STATE_START and stopping network device,
> kernel cannot disable the interrupts due to the condition
> "netif_running(netdev)" in the ISR. Hence, kernel will hang due to the
> continuous interruption of the network device.
> 
> In order to solve the above problem, the interrupts of the network device
> should always be disabled in the ISR without being restricted by the
> condition "netif_running(netdev)".
> 
> [V2]
> Remove unnecessary curly braces.
> 
> Signed-off-by: Vincent Chen <vincentc@andestech.com>

Applied.