Don't assert held dma-buf reservation lock on memory mapping of exported buffer. We're going to change dma-buf mmap() locking policy such that exporters will have to handle the lock. The previous locking policy caused deadlock problem for DRM drivers in a case of self-imported dma-bufs, it's solved by moving the lock down to exporters. Fixes: 27f3733a1049 ("dma-buf/heaps: Assert held reservation lock for dma-buf mmapping") Signed-off-by: Dmitry Osipenko <dmitry.osipenko@xxxxxxxxxxxxx> --- drivers/dma-buf/heaps/cma_heap.c | 3 --- drivers/dma-buf/heaps/system_heap.c | 3 --- 2 files changed, 6 deletions(-) diff --git a/drivers/dma-buf/heaps/cma_heap.c b/drivers/dma-buf/heaps/cma_heap.c index 1131fb943992..28fb04eccdd0 100644 --- a/drivers/dma-buf/heaps/cma_heap.c +++ b/drivers/dma-buf/heaps/cma_heap.c @@ -13,7 +13,6 @@ #include <linux/dma-buf.h> #include <linux/dma-heap.h> #include <linux/dma-map-ops.h> -#include <linux/dma-resv.h> #include <linux/err.h> #include <linux/highmem.h> #include <linux/io.h> @@ -183,8 +182,6 @@ static int cma_heap_mmap(struct dma_buf *dmabuf, struct vm_area_struct *vma) { struct cma_heap_buffer *buffer = dmabuf->priv; - dma_resv_assert_held(dmabuf->resv); - if ((vma->vm_flags & (VM_SHARED | VM_MAYSHARE)) == 0) return -EINVAL; diff --git a/drivers/dma-buf/heaps/system_heap.c b/drivers/dma-buf/heaps/system_heap.c index e8bd10e60998..fcf836ba9c1f 100644 --- a/drivers/dma-buf/heaps/system_heap.c +++ b/drivers/dma-buf/heaps/system_heap.c @@ -13,7 +13,6 @@ #include <linux/dma-buf.h> #include <linux/dma-mapping.h> #include <linux/dma-heap.h> -#include <linux/dma-resv.h> #include <linux/err.h> #include <linux/highmem.h> #include <linux/mm.h> @@ -202,8 +201,6 @@ static int system_heap_mmap(struct dma_buf *dmabuf, struct vm_area_struct *vma) struct sg_page_iter piter; int ret; - dma_resv_assert_held(dmabuf->resv); - for_each_sgtable_page(table, &piter, vma->vm_pgoff) { struct page *page = sg_page_iter_page(&piter); -- 2.39.2