diff options
| author | Tudor Ambarus <tudor.ambarus@microchip.com> | 2022-10-25 12:02:42 +0300 |
|---|---|---|
| committer | Vinod Koul <vkoul@kernel.org> | 2022-11-08 08:13:57 +0300 |
| commit | 06988949df8c3007ad82036d3606d8ae72ed9000 (patch) | |
| tree | c3c901807d30b0e9398b33f5f6f1679be6e82337 | |
| parent | c6babed879fbe82796a601bf097649e07382db46 (diff) | |
| download | linux-06988949df8c3007ad82036d3606d8ae72ed9000.tar.xz | |
dmaengine: at_hdmac: Fix concurrency over descriptor
The descriptor was added to the free_list before calling the callback,
which could result in reissuing of the same descriptor and calling of a
single callback for both. Move the decriptor to the free list after the
callback is invoked.
Fixes: dc78baa2b90b ("dmaengine: at_hdmac: new driver for the Atmel AHB DMA Controller")
Reported-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/lkml/13c6c9a2-6db5-c3bf-349b-4c127ad3496a@axentia.se/
Acked-by: Nicolas Ferre <nicolas.ferre@microchip.com>
Link: https://lore.kernel.org/r/20221025090306.297886-1-tudor.ambarus@microchip.com
Link: https://lore.kernel.org/r/20221025090306.297886-9-tudor.ambarus@microchip.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
| -rw-r--r-- | drivers/dma/at_hdmac.c | 14 |
1 files changed, 9 insertions, 5 deletions
diff --git a/drivers/dma/at_hdmac.c b/drivers/dma/at_hdmac.c index f1e6fa6af6c2..2012ecc57826 100644 --- a/drivers/dma/at_hdmac.c +++ b/drivers/dma/at_hdmac.c @@ -469,11 +469,8 @@ atc_chain_complete(struct at_dma_chan *atchan, struct at_desc *desc) desc->memset_buffer = false; } - /* move children to free_list */ - list_splice_init(&desc->tx_list, &atchan->free_list); - /* move myself to free_list */ - list_move(&desc->desc_node, &atchan->free_list); - + /* Remove transfer node from the active list. */ + list_del_init(&desc->desc_node); spin_unlock_irqrestore(&atchan->lock, flags); dma_descriptor_unmap(txd); @@ -483,6 +480,13 @@ atc_chain_complete(struct at_dma_chan *atchan, struct at_desc *desc) dmaengine_desc_get_callback_invoke(txd, NULL); dma_run_dependencies(txd); + + spin_lock_irqsave(&atchan->lock, flags); + /* move children to free_list */ + list_splice_init(&desc->tx_list, &atchan->free_list); + /* add myself to free_list */ + list_add(&desc->desc_node, &atchan->free_list); + spin_unlock_irqrestore(&atchan->lock, flags); } /** |