Am 25.06.24 um 14:41 schrieb Pierre-Eric Pelloux-Prayer:
The call to radeon_vm_clear_freed might clear bo_va->bo, so
we have to check it before dereferencing it.
Signed-off-by: Pierre-Eric Pelloux-Prayer <pierre-eric.pelloux-prayer@xxxxxxx>
---
drivers/gpu/drm/radeon/radeon_gem.c | 11 ++++++++++-
1 file changed, 10 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/radeon/radeon_gem.c b/drivers/gpu/drm/radeon/radeon_gem.c
index 3fec3acdaf28..0cf1a72091b7 100644
--- a/drivers/gpu/drm/radeon/radeon_gem.c
+++ b/drivers/gpu/drm/radeon/radeon_gem.c
@@ -641,8 +641,17 @@ static void radeon_gem_va_update_vm(struct radeon_device *rdev,
if (r)
goto error_unlock;
- if (bo_va->it.start)
+ if (bo_va->it.start) {
+ if (bo_va->bo == NULL) {
In the kernel you should probably use !bo_va->bo instead.
+ /* Buggy userspace can try to use RADEON_VA_UNMAP after
+ * closing the BO. In this case, radeon_vm_clear_freed
+ * will unset bo_va->bo.
+ */
I think you can drop that comment, it's perfectly valid for userspace to
unmap a region after closing the BO.
It's just that the radeon VM support was never designed very well.
Regards,
Christian.
+ r = -ENOENT;
+ goto error_unlock;
+ }
r = radeon_vm_bo_update(rdev, bo_va, bo_va->bo->tbo.resource);
+ }
error_unlock:
mutex_unlock(&bo_va->vm->mutex);
