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Date:   Tue, 16 Mar 2021 16:15:58 +0530
From:   Vinod Koul <vkoul@kernel.org>
To:     Lars-Peter Clausen <lars@metafoo.de>
Cc:     Michal Simek <michal.simek@xilinx.com>,
        Radhey Shyam Pandey <radhey.shyam.pandey@xilinx.com>,
        Shravya Kumbham <shravya.kumbham@xilinx.com>,
        dmaengine@vger.kernel.org
Subject: Re: [PATCH] dmaengine: xilinx: Introduce synchronize() callback
Message-ID: <YFCMZthQen6RaFfU@vkoul-mobl>
References: <20210313125311.4823-1-lars@metafoo.de>
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On 13-03-21, 13:53, Lars-Peter Clausen wrote:
> The Xilinx dmaengine driver uses a tasklet to process completed
> descriptors and execute their callbacks.
> 
> Currently consumers of the DMA channel have to no method of synchronization
> against this tasklet when using the Xilinx dmaengine drivers. This can lead
> to race conditions when the consumer frees resources that are accessed in
> the callback before the tasklet has finished running.
> 
> It is not enough to just call dmaengine_terminal_all() since on a
> multi-processor system the tasklet can run concurrently to it and might
> call the callback after dmaengine_terminate_all() has already finished.
> 
> To mitigate this issue implement the synchronize() callback for the driver,
> which will wait until the tasklet has finished.

Applied, thanks

-- 
~Vinod