From: Daniel Mentz Date: Wed, 16 Dec 2015 01:38:48 +0000 (-0800) Subject: dma-debug: Fix dma_debug_entry offset calculation X-Git-Tag: v3.14.62~11 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=a5d32c261d991edad56c93d2b1244225dcea561b;p=thirdparty%2Fkernel%2Fstable.git dma-debug: Fix dma_debug_entry offset calculation commit 0354aec19ce3d355c6213b0434064efc25c9b22c upstream. 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. Fixes: 0abdd7a81b7e ("dma-debug: introduce debug_dma_assert_idle()") Signed-off-by: Daniel Mentz Signed-off-by: Dan Williams Signed-off-by: Greg Kroah-Hartman --- diff --git a/lib/dma-debug.c b/lib/dma-debug.c index 98f2d7e91a911..1c741f9000284 100644 --- a/lib/dma-debug.c +++ b/lib/dma-debug.c @@ -1440,7 +1440,7 @@ 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; @@ -1456,7 +1456,7 @@ 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,