This is a note to let you know that I've just added the patch titled
iio: frequency: ad9523: Fix alignment for DMA safety
to the 5.18-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
iio-frequency-ad9523-fix-alignment-for-dma-safety.patch
and it can be found in the queue-5.18 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 51b90a9d166c1c5ecaf9d2b0f9aa112167946627
Author: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx>
Date: Sun May 8 18:56:45 2022 +0100
iio: frequency: ad9523: Fix alignment for DMA safety
[ Upstream commit 8ff2eb625c353b1491d9f89f1dfd52e7aef5734c ]
____cacheline_aligned is an insufficient guarantee for non-coherent DMA
on platforms with 128 byte cachelines above L1. Switch to the updated
IIO_DMA_MINALIGN definition.
Updated help text to 'may' require buffers to be in their own cacheline.
Fixes: cd1678f96329 ("iio: frequency: New driver for AD9523 SPI Low Jitter Clock Generator")
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx>
Acked-by: Nuno Sá <nuno.sa@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20220508175712.647246-66-jic23@xxxxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/iio/frequency/ad9523.c b/drivers/iio/frequency/ad9523.c
index a0f92c336fc4..31c97f9f2c1b 100644
--- a/drivers/iio/frequency/ad9523.c
+++ b/drivers/iio/frequency/ad9523.c
@@ -287,13 +287,13 @@ struct ad9523_state {
struct mutex lock;
/*
- * DMA (thus cache coherency maintenance) requires the
- * transfer buffers to live in their own cache lines.
+ * DMA (thus cache coherency maintenance) may require that
+ * transfer buffers live in their own cache lines.
*/
union {
__be32 d32;
u8 d8[4];
- } data[2] ____cacheline_aligned;
+ } data[2] __aligned(IIO_DMA_MINALIGN);
};
static int ad9523_read(struct iio_dev *indio_dev, unsigned int addr)
