Re: [Linux-stable-mirror] [PATCH] drm/ttm: Fix 'buf' pointer update in ttm_bo_vm_access_kmap() (v2)

Greg and other stable maintainers please ignore this one.

Tom just misunderstood, what to do with this patch.

Thanks, Christian.

Am 29.01.2018 um 15:34 schrieb Tom St Denis:

The buf pointer was not being incremented inside the loop meaning the same block of data would be read or written repeatedly.

Fixes: 09ac4fcb3f25 ("drm/ttm: Implement vm_operations_struct.access v2")

Signed-off-by: Tom St Denis tom.stdenis@amd.com Reviewed-by: Christian König christian.koenig@amd.com

(v2) Change 'buf' pointer to uint8_t* type

drivers/gpu/drm/ttm/ttm_bo_vm.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/ttm/ttm_bo_vm.c b/drivers/gpu/drm/ttm/ttm_bo_vm.c index 08a3c324242e..60fcef1593dd 100644 --- a/drivers/gpu/drm/ttm/ttm_bo_vm.c +++ b/drivers/gpu/drm/ttm/ttm_bo_vm.c @@ -316,7 +316,7 @@ static void ttm_bo_vm_close(struct vm_area_struct *vma) static int ttm_bo_vm_access_kmap(struct ttm_buffer_object *bo, unsigned long offset,

• 		 void *buf, int len, int write)
  

• 		 uint8_t *buf, int len, int write)
  

  { unsigned long page = offset >> PAGE_SHIFT; unsigned long bytes_left = len;

@@ -345,6 +345,7 @@ static int ttm_bo_vm_access_kmap(struct ttm_buffer_object *bo, ttm_bo_kunmap(&map); page++;

• buf += bytes;
  

  bytes_left -= bytes; offset = 0; } while (bytes_left);