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> } > + > + // If necessary, create an SGTable for the gem object and register a= Devres for it to ensure > + // that it is unmapped on driver unbind. > + fn get_sg_table<'a>( > + &'a self, > + dev: &'a device::Device, Just noticed that the caller can technically pass a different `dev` from the one the buffer will be mapped onto, potentially linking the `Devres` (and thus the device mapping) to a completely unrelated lifetime. I.e. `dev` is only used to create the `Devres`, while `drm_gem_shmem_get_pages_sgt_locked` uses the object's device pointer to create the mapping. We need to add the check ensuring that the two point to the same device: let expected =3D self.dev().as_ref().as_raw(); if dev.as_raw() !=3D expected { return Err(EINVAL); } Ideally we could do without the `dev` argument altogether, but that's our only guarantee that the device is bound, so I don't think we can do without this runtime check. I think it's also worth mentioning in the documentations of `sg_table` and `owned_sg_table` which device is expected.