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Date:   Mon, 5 Oct 2020 09:57:47 +0530
From:   Vinod Koul <vkoul@kernel.org>
To:     Paul Cercueil <paul@crapouillou.net>
Cc:     od@zcrc.me, dmaengine@vger.kernel.org,
        linux-kernel@vger.kernel.org, stable@vger.kernel.org,
        Artur Rojek <contact@artur-rojek.eu>
Subject: Re: [PATCH] dma: dma-jz4780: Fix race in jz4780_dma_tx_status
Message-ID: <20201005042747.GC2968@vkoul-mobl>
References: <20201004140307.885556-1-paul@crapouillou.net>
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On 04-10-20, 16:03, Paul Cercueil wrote:
> The jz4780_dma_tx_status() function would check if a channel's cookie
> state was set to 'completed', and if not, it would enter the critical
> section. However, in that time frame, the jz4780_dma_chan_irq() function
> was able to set the cookie to 'completed', and clear the jzchan->vchan
> pointer, which was deferenced in the critical section of the first
> function.
> 
> Fix this race by checking the channel's cookie state after entering the
> critical function and not before.

Applied, thanks

-- 
~Vinod