summary refs log tree commit diff
path: root/lib/dma-debug.c
diff options
context:
space:
mode:
authorDaniel Mentz <danielmentz@google.com>2015-12-15 17:38:48 -0800
committerDan Williams <dan.j.williams@intel.com>2015-12-16 11:24:26 -0800
commit0354aec19ce3d355c6213b0434064efc25c9b22c (patch)
treed428458458507a455257e0eec6c92ab5917e50df /lib/dma-debug.c
parent3e6110fd5480f5f86ff31381f4dea14218284bff (diff)
downloadlinux-0354aec19ce3d355c6213b0434064efc25c9b22c.tar.gz
dma-debug: Fix dma_debug_entry offset calculation
dma-debug uses struct dma_debug_entry to keep track of dma coherent
memory allocation requests. The virtual address is converted into a pfn
and an offset. Previously, the offset was calculated using an incorrect
bit mask.  As a result, we saw incorrect error messages from dma-debug
like the following:

"DMA-API: exceeded 7 overlapping mappings of cacheline 0x03e00000"

Cacheline 0x03e00000 does not exist on our platform.

Cc: <stable@vger.kernel.org>
Fixes: 0abdd7a81b7e ("dma-debug: introduce debug_dma_assert_idle()")
Signed-off-by: Daniel Mentz <danielmentz@google.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Diffstat (limited to 'lib/dma-debug.c')
-rw-r--r--lib/dma-debug.c4
1 files changed, 2 insertions, 2 deletions
diff --git a/lib/dma-debug.c b/lib/dma-debug.c
index 8855f019ebe8..d34bd24c2c84 100644
--- a/lib/dma-debug.c
+++ b/lib/dma-debug.c
@@ -1464,7 +1464,7 @@ void debug_dma_alloc_coherent(struct device *dev, size_t size,
 	entry->type      = dma_debug_coherent;
 	entry->dev       = dev;
 	entry->pfn	 = page_to_pfn(virt_to_page(virt));
-	entry->offset	 = (size_t) virt & PAGE_MASK;
+	entry->offset	 = (size_t) virt & ~PAGE_MASK;
 	entry->size      = size;
 	entry->dev_addr  = dma_addr;
 	entry->direction = DMA_BIDIRECTIONAL;
@@ -1480,7 +1480,7 @@ void debug_dma_free_coherent(struct device *dev, size_t size,
 		.type           = dma_debug_coherent,
 		.dev            = dev,
 		.pfn		= page_to_pfn(virt_to_page(virt)),
-		.offset		= (size_t) virt & PAGE_MASK,
+		.offset		= (size_t) virt & ~PAGE_MASK,
 		.dev_addr       = addr,
 		.size           = size,
 		.direction      = DMA_BIDIRECTIONAL,