[Intel-gfx] [PATCH v1 1/7] Revert "media: videobuf2: Assert held reservation lock for dma-buf mmapping"

Dmitry Osipenko dmitry.osipenko at collabora.com
Sun Apr 2 16:48:20 UTC 2023


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: 3a6ca1810f77 ("media: videobuf2: Assert held reservation lock for dma-buf mmapping")
Signed-off-by: Dmitry Osipenko <dmitry.osipenko at collabora.com>
---
 drivers/media/common/videobuf2/videobuf2-dma-contig.c | 3 ---
 drivers/media/common/videobuf2/videobuf2-dma-sg.c     | 3 ---
 drivers/media/common/videobuf2/videobuf2-vmalloc.c    | 3 ---
 3 files changed, 9 deletions(-)

diff --git a/drivers/media/common/videobuf2/videobuf2-dma-contig.c b/drivers/media/common/videobuf2/videobuf2-dma-contig.c
index 205d3cac425c..2fa455d4a048 100644
--- a/drivers/media/common/videobuf2/videobuf2-dma-contig.c
+++ b/drivers/media/common/videobuf2/videobuf2-dma-contig.c
@@ -11,7 +11,6 @@
  */
 
 #include <linux/dma-buf.h>
-#include <linux/dma-resv.h>
 #include <linux/module.h>
 #include <linux/refcount.h>
 #include <linux/scatterlist.h>
@@ -456,8 +455,6 @@ static int vb2_dc_dmabuf_ops_vmap(struct dma_buf *dbuf, struct iosys_map *map)
 static int vb2_dc_dmabuf_ops_mmap(struct dma_buf *dbuf,
 	struct vm_area_struct *vma)
 {
-	dma_resv_assert_held(dbuf->resv);
-
 	return vb2_dc_mmap(dbuf->priv, vma);
 }
 
diff --git a/drivers/media/common/videobuf2/videobuf2-dma-sg.c b/drivers/media/common/videobuf2/videobuf2-dma-sg.c
index 183037fb1273..28f3fdfe23a2 100644
--- a/drivers/media/common/videobuf2/videobuf2-dma-sg.c
+++ b/drivers/media/common/videobuf2/videobuf2-dma-sg.c
@@ -10,7 +10,6 @@
  * the Free Software Foundation.
  */
 
-#include <linux/dma-resv.h>
 #include <linux/module.h>
 #include <linux/mm.h>
 #include <linux/refcount.h>
@@ -498,8 +497,6 @@ static int vb2_dma_sg_dmabuf_ops_vmap(struct dma_buf *dbuf,
 static int vb2_dma_sg_dmabuf_ops_mmap(struct dma_buf *dbuf,
 	struct vm_area_struct *vma)
 {
-	dma_resv_assert_held(dbuf->resv);
-
 	return vb2_dma_sg_mmap(dbuf->priv, vma);
 }
 
diff --git a/drivers/media/common/videobuf2/videobuf2-vmalloc.c b/drivers/media/common/videobuf2/videobuf2-vmalloc.c
index a6c6d2fcaaa4..7c635e292106 100644
--- a/drivers/media/common/videobuf2/videobuf2-vmalloc.c
+++ b/drivers/media/common/videobuf2/videobuf2-vmalloc.c
@@ -10,7 +10,6 @@
  * the Free Software Foundation.
  */
 
-#include <linux/dma-resv.h>
 #include <linux/io.h>
 #include <linux/module.h>
 #include <linux/mm.h>
@@ -319,8 +318,6 @@ static int vb2_vmalloc_dmabuf_ops_vmap(struct dma_buf *dbuf,
 static int vb2_vmalloc_dmabuf_ops_mmap(struct dma_buf *dbuf,
 	struct vm_area_struct *vma)
 {
-	dma_resv_assert_held(dbuf->resv);
-
 	return vb2_vmalloc_mmap(dbuf->priv, vma);
 }
 
-- 
2.39.2



More information about the Intel-gfx mailing list