Applied "spi: davinci: do not use DMA for vmalloc'ed buffers" to the spi tree

Mark Brown broonie at
Wed Mar 15 12:37:11 PDT 2017

The patch

   spi: davinci: do not use DMA for vmalloc'ed buffers

has been applied to the spi tree at


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>From 4dd9becbce4f10009322c3e2297f9db3ace94a10 Mon Sep 17 00:00:00 2001
From: Frode Isaksen <fisaksen at>
Date: Thu, 23 Feb 2017 19:02:00 +0100
Subject: [PATCH] spi: davinci: do not use DMA for vmalloc'ed buffers

Using vmalloc'ed buffers will fail since daVinci has
VIVT cache and only the kernel lowmem virtual address
is invalidated/flushed when performing DMA.
The virtual address returned from vmalloc() is not
invalidated/flushed and may contain stale data when
returning from spi_sync().
Fixes errors when running UBIFS over SPI NOR.
Revert this when all upper layer users of vmalloc'ed
buffers sent to SPI handles cache flushing/invalidating.

Signed-off-by: Frode Isaksen <fisaksen at>
Signed-off-by: Mark Brown <broonie at>
 drivers/spi/spi-davinci.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/spi/spi-davinci.c b/drivers/spi/spi-davinci.c
index 75c658e4e487..f37bbdd18d61 100644
--- a/drivers/spi/spi-davinci.c
+++ b/drivers/spi/spi-davinci.c
@@ -482,7 +482,9 @@ static bool davinci_spi_can_dma(struct spi_master *master,
 	if (spicfg)
 		can_dma = (spicfg->io_type == SPI_IO_TYPE_DMA) &&
-			(xfer->len >= DMA_MIN_BYTES);
+			(xfer->len >= DMA_MIN_BYTES) &&
+			!is_vmalloc_addr(xfer->rx_buf) &&
+			!is_vmalloc_addr(xfer->tx_buf);
 	return can_dma;

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