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Subject: Re: [PATCH 05/10] dmaengine: bcm2835-dma: Use vchan_terminate_vdesc()
 instead of desc_free
To: Eric Anholt <eric@anholt.net>, <vinod.koul@intel.com>
CC: <linux-arm-kernel@lists.infradead.org>, <dmaengine@vger.kernel.org>,
        <linux-kernel@vger.kernel.org>, <lars@metafoo.de>,
        Martin Sperl <kernel@martin.sperl.org>
References: <20171114143212.8311-1-peter.ujfalusi@ti.com>
 <20171114143212.8311-6-peter.ujfalusi@ti.com> <87k1yr4blm.fsf@anholt.net>
From: Peter Ujfalusi <peter.ujfalusi@ti.com>
Message-ID: <2f3d48dd-f6a8-a3ff-635e-296f3e0f75f1@ti.com>
Date: Tue, 21 Nov 2017 13:42:27 +0200
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Eric,

On 11/15/2017 08:53 PM, Eric Anholt wrote:
> Peter Ujfalusi <peter.ujfalusi@ti.com> writes:
> 
>> To avoid race with vchan_complete, use the race free way to terminate
>> running transfer.
>>
>> Implement the device_synchronize callback to make sure that the terminated
>> descriptor is freed.
>>
>> CC: Martin Sperl <kernel@martin.sperl.org>
>> CC: Eric Anholt <eric@anholt.net>
>> Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
> 
> I haven't fully followed the series, but thanks for porting your fix to
> other platforms!
I have seen similar patterns in these drivers and it was the right thing to do
imho.
Unfortunately I can not test on other platforms than eDMA and sDMA, but I
firmly believe that based on the usage it should be fine as it survives my
torture tests.

It would be great to see some Tested-by from others to have more coverage.

> Acked-by: Eric Anholt <eric@anholt.net>

Thank you!


-- 
Péter

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