Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 0366901b authored by Tudor Ambarus's avatar Tudor Ambarus Committed by Greg Kroah-Hartman
Browse files

dmaengine: at_xdmac: Fix concurrency over xfers_list 



commit 18deddea9184b62941395889ff7659529c877326 upstream.

Since tx_submit can be called from a hard IRQ, xfers_list must be
protected with a lock to avoid concurency on the list's elements.
Since at_xdmac_handle_cyclic() is called from a tasklet, spin_lock_irq
is enough to protect from a hard IRQ.

Fixes: e1f7c9ee ("dmaengine: at_xdmac: creation of the atmel eXtended DMA Controller driver")
Signed-off-by: default avatarTudor Ambarus <tudor.ambarus@microchip.com>
Link: https://lore.kernel.org/r/20211215110115.191749-8-tudor.ambarus@microchip.com


Signed-off-by: default avatarVinod Koul <vkoul@kernel.org>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent d56e1fcb

drivers/dma/at_xdmac.c

+10 −7
Original line number Diff line number Diff line
@@ -1564,15 +1564,18 @@ static void at_xdmac_handle_cyclic(struct at_xdmac_chan *atchan) 
	struct at_xdmac_desc		*desc;

	struct dma_async_tx_descriptor	*txd;



	if (!list_empty(&atchan->xfers_list)) {

		desc = list_first_entry(&atchan->xfers_list,

					struct at_xdmac_desc, xfer_node);

	spin_lock_irq(&atchan->lock);

	if (list_empty(&atchan->xfers_list)) {

		spin_unlock_irq(&atchan->lock);

		return;

	}

	desc = list_first_entry(&atchan->xfers_list, struct at_xdmac_desc,

				xfer_node);

	spin_unlock_irq(&atchan->lock);

	txd = &desc->tx_dma_desc;



	if (txd->flags & DMA_PREP_INTERRUPT)

		dmaengine_desc_get_callback_invoke(txd, NULL);

}

}



static void at_xdmac_handle_error(struct at_xdmac_chan *atchan)

{