Use separate flag for tracking page count bumped by shmem->sgt to avoid imbalanced page counter during of drm_gem_shmem_free() time. It's fragile to assume that populated shmem->pages at a freeing time means that the count was bumped by drm_gem_shmem_get_pages_sgt(), using a flag removes the ambiguity.
Signed-off-by: Dmitry Osipenko <[email protected]> --- drivers/gpu/drm/drm_gem_shmem_helper.c | 3 ++- drivers/gpu/drm/lima/lima_gem.c | 1 + include/drm/drm_gem_shmem_helper.h | 7 +++++++ 3 files changed, 10 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/drm_gem_shmem_helper.c b/drivers/gpu/drm/drm_gem_shmem_helper.c index 78d9cf2355a5..db20b9123891 100644 --- a/drivers/gpu/drm/drm_gem_shmem_helper.c +++ b/drivers/gpu/drm/drm_gem_shmem_helper.c @@ -152,7 +152,7 @@ void drm_gem_shmem_free(struct drm_gem_shmem_object *shmem) sg_free_table(shmem->sgt); kfree(shmem->sgt); } - if (shmem->pages) + if (shmem->got_sgt) drm_gem_shmem_put_pages(shmem); drm_WARN_ON(obj->dev, shmem->pages_use_count); @@ -687,6 +687,7 @@ static struct sg_table *drm_gem_shmem_get_pages_sgt_locked(struct drm_gem_shmem_ if (ret) goto err_free_sgt; + shmem->got_sgt = true; shmem->sgt = sgt; return sgt; diff --git a/drivers/gpu/drm/lima/lima_gem.c b/drivers/gpu/drm/lima/lima_gem.c index 4f9736e5f929..28602302c281 100644 --- a/drivers/gpu/drm/lima/lima_gem.c +++ b/drivers/gpu/drm/lima/lima_gem.c @@ -89,6 +89,7 @@ int lima_heap_alloc(struct lima_bo *bo, struct lima_vm *vm) } *bo->base.sgt = sgt; + bo->base.got_sgt = true; if (vm) { ret = lima_vm_map_bo(vm, bo, old_size >> PAGE_SHIFT); diff --git a/include/drm/drm_gem_shmem_helper.h b/include/drm/drm_gem_shmem_helper.h index ec70a98a8fe1..f87124629bb5 100644 --- a/include/drm/drm_gem_shmem_helper.h +++ b/include/drm/drm_gem_shmem_helper.h @@ -73,6 +73,13 @@ struct drm_gem_shmem_object { */ unsigned int vmap_use_count; + /** + * @got_sgt: + * + * True if SG table was retrieved using drm_gem_shmem_get_pages_sgt() + */ + bool got_sgt : 1; + /** * @imported_sgt: * -- 2.41.0
