[PATCH] drm/exynos: fix layering violation of address

Joonyoung Shim jy0922.shim at samsung.com
Tue Sep 15 22:16:45 PDT 2015


There is no guarantee that DMA addresses are the same as physical
addresses, but dma_to_pfn() knows how to convert a dma_addr_t to a PFN
which can then be converted to a struct page.

Suggested-by: Russell King <rmk+kernel at arm.linux.org.uk>
Signed-off-by: Joonyoung Shim <jy0922.shim at samsung.com>
---
 drivers/gpu/drm/exynos/exynos_drm_gem.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/exynos/exynos_drm_gem.c b/drivers/gpu/drm/exynos/exynos_drm_gem.c
index f12fbc3..a4fb78e 100644
--- a/drivers/gpu/drm/exynos/exynos_drm_gem.c
+++ b/drivers/gpu/drm/exynos/exynos_drm_gem.c
@@ -77,7 +77,8 @@ static int exynos_drm_alloc_buf(struct exynos_drm_gem_obj *obj)
 
 		start_addr = obj->dma_addr;
 		while (i < nr_pages) {
-			obj->pages[i] = phys_to_page(start_addr);
+			obj->pages[i] = pfn_to_page(dma_to_pfn(dev->dev,
+							       start_addr));
 			start_addr += PAGE_SIZE;
 			i++;
 		}
-- 
1.9.1



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