dmaengine: mv_xor: Fix incorrect offset in dma_map_page()

Upon booting, I occasionally spotted some BUGs triggered by the internal
DMA test routine executed upon driver probing. This was detected by
SLUB_DEBUG ("Freechain corrupt" or "Redzone overwritten"). Tracking
this down located a problem in passing 0 as offset in dma_map_page().
As kmalloc, especially when used with SLUB_DEBUG, may return a non page
aligned address.

This patch fixes this issue by passing the correct offset in
dma_map_page().

Tested on a custom Armada XP board.

Signed-off-by: Stefan Roese <sr@denx.de>
Cc: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Cc: Gregory CLEMENT <gregory.clement@free-electrons.com>
Cc: Marcin Wojtas <mw@semihalf.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

1 files changed, 6 insertions, 4 deletions

diff --git a/drivers/dma/mv_xor.c b/drivers/dma/mv_xor.c
index 25d1dadcddd1..d0446a75990a 100644
--- a/drivers/dma/mv_xor.c
+++ b/drivers/dma/mv_xor.c
@@ -703,8 +703,9 @@ static int mv_chan_memcpy_self_test(struct mv_xor_chan *mv_chan)
                 goto free_resources;
         }
 
-        src_dma = dma_map_page(dma_chan->device->dev, virt_to_page(src), 0,
-                                 PAGE_SIZE, DMA_TO_DEVICE);
+        src_dma = dma_map_page(dma_chan->device->dev, virt_to_page(src),
+                               (size_t)src & ~PAGE_MASK, PAGE_SIZE,
+                               DMA_TO_DEVICE);
         unmap->addr[0] = src_dma;
 
         ret = dma_mapping_error(dma_chan->device->dev, src_dma);
@@ -714,8 +715,9 @@ static int mv_chan_memcpy_self_test(struct mv_xor_chan *mv_chan)
         }
         unmap->to_cnt = 1;
 
-        dest_dma = dma_map_page(dma_chan->device->dev, virt_to_page(dest), 0,
-                                  PAGE_SIZE, DMA_FROM_DEVICE);
+        dest_dma = dma_map_page(dma_chan->device->dev, virt_to_page(dest),
+                                (size_t)dest & ~PAGE_MASK, PAGE_SIZE,
+                                DMA_FROM_DEVICE);
         unmap->addr[1] = dest_dma;
 
         ret = dma_mapping_error(dma_chan->device->dev, dest_dma);