[PATCH AUTOSEL 4.4 29/92] dmaengine: at_xdmac: remove BUG_ON macro in tasklet

Sasha Levin
2019-05-22T19:32:36Z

From: Nicolas Ferre <nicolas.ferre@microchip.com>

[ Upstream commit e2c114c06da2d9ffad5b16690abf008d6696f689 ]

Even if this case shouldn't happen when controller is properly programmed,
it's still better to avoid dumping a kernel Oops for this.
As the sequence may happen only for debugging purposes, log the error and
just finish the tasklet call.

Signed-off-by: Nicolas Ferre <nicolas.ferre@microchip.com>
Acked-by: Ludovic Desroches <ludovic.desroches@microchip.com>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/dma/at_xdmac.c | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/dma/at_xdmac.c b/drivers/dma/at_xdmac.c
index af24c5bf32d69..8aa3ccf42e55a 100644
--- a/drivers/dma/at_xdmac.c
+++ b/drivers/dma/at_xdmac.c
@@ -1608,7 +1608,11 @@ static void at_xdmac_tasklet(unsigned long data)
struct at_xdmac_desc,
xfer_node);
dev_vdbg(chan2dev(&atchan->chan), "%s: desc 0x%p\n", __func__, desc);
- BUG_ON(!desc->active_xfer);
+ if (!desc->active_xfer) {
+ dev_err(chan2dev(&atchan->chan), "Xfer not active: exiting");
+ spin_unlock_bh(&atchan->lock);
+ return;
+ }

txd = &desc->tx_dma_desc;

--
2.20.1