Re: [PATCH V2] dma: tegra: avoid channel lock up after free

[Laxman Dewangan]

On Tuesday 30 October 2012 04:50 AM, Dmitry Osipenko wrote:
> Fixed channel "lock up" after free.
>
> Lock scenario: Channel 1 was allocated and prepared as slave_sg, used and freed.
> Now preparation of cyclic dma on channel 1 will fail with err "DMA configuration
> conflict" because tdc->isr_handler still selected to handle_once_dma_done.
>
> This happens because tegra_dma_abort_all() won't be called on channel freeing
> if pending list is empty or channel not busy. We need to clear isr_handler
> on channel freeing to avoid locking. Also I added small optimization to prepare
> functions, so current channel type checked before making allocations.
>
> Signed-off-by: Dmitry Osipenko<digetx@xxxxxxxxx>
> ---

Looks good to me.
Acked-by: Laxman Dewangan <ldewangan@xxxxxxxxxx>

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