[PATCH 7/7] dmaengine: zynqmp_dma: fix lockdep warning in tasklet
Michael Tretter
m.tretter at pengutronix.de
Thu Aug 26 02:47:42 PDT 2021
The tasklet that handles the completed dma transfers uses spin_unlock
for unlocking a spin lock that was previously locked with
spin_lock_irqsave.
This caused the following lockdep warning about an inconsistent lock
state:
inconsistent {HARDIRQ-ON-W} -> {IN-HARDIRQ-W} usage.
We must use spin_lock_irqsave, because it is possible to queue DMA
transfers from an irq handler.
Replace the spin_unlock and spin_lock by spin_unlock_irqrestore and
spin_lock_irqsave.
Signed-off-by: Michael Tretter <m.tretter at pengutronix.de>
---
drivers/dma/xilinx/zynqmp_dma.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/dma/xilinx/zynqmp_dma.c b/drivers/dma/xilinx/zynqmp_dma.c
index ef32f7519e0a..5f5f9e244ec6 100644
--- a/drivers/dma/xilinx/zynqmp_dma.c
+++ b/drivers/dma/xilinx/zynqmp_dma.c
@@ -612,9 +612,9 @@ static void zynqmp_dma_chan_desc_cleanup(struct zynqmp_dma_chan *chan)
callback = desc->async_tx.callback;
callback_param = desc->async_tx.callback_param;
if (callback) {
- spin_unlock(&chan->lock);
+ spin_unlock_irqrestore(&chan->lock, irqflags);
callback(callback_param);
- spin_lock(&chan->lock);
+ spin_lock_irqsave(&chan->lock, irqflags);
}
/* Run any dependencies, then free the descriptor */
--
2.30.2
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