Subject: Re: [PATCH v1] drm: import DMA_BUF module namespace

From: Thomas Zimmermann <[email-masked]>
Date: Wed, 27 Oct 2021 20:30:34 +0200

Hi,

thanks for the patch.

Am 27.10.21 um 17:25 schrieb Marcel Ziswiler:
> From: Marcel Ziswiler <[email-masked]>
> 
> Today's -next fails building arm64 defconfig as follows:
> 
> ERROR: modpost: module drm_cma_helper uses symbol dma_buf_vunmap from
>   namespace DMA_BUF, but does not import it.
> ERROR: modpost: module drm_cma_helper uses symbol dma_buf_vmap from
>   namespace DMA_BUF, but does not import it.
> 
> Reported-by: Linux Kernel Functional Testing <[email-masked]>
> Fixes: commit 4b2b5e142ff4 ("drm: Move GEM memory managers into modules")
> Signed-off-by: Marcel Ziswiler <[email-masked]>
> 
> ---
> 
>   drivers/gpu/drm/drm_gem_cma_helper.c | 2 ++
>   1 file changed, 2 insertions(+)
> 
> diff --git a/drivers/gpu/drm/drm_gem_cma_helper.c b/drivers/gpu/drm/drm_gem_cma_helper.c
> index 6f7b3f8ec04d3..69f8564ad11cd 100644
> --- a/drivers/gpu/drm/drm_gem_cma_helper.c
> +++ b/drivers/gpu/drm/drm_gem_cma_helper.c
> @@ -23,6 +23,8 @@
>   #include <drm/drm_gem_cma_helper.h>
>   #include <drm/drm_vma_manager.h>
>   
> +MODULE_IMPORT_NS(DMA_BUF);

Could this line be moved to the bottom of the file, where the other 
MODULE statements are?

In the fixed commit 4b2b5e142ff4, there's a similar change for 
drm_gem_shmem_helper.c. It uses dma-buf_vmap as well. Does that module 
require the same fix?

Do you have any idea why I don't see these errors in my builds?

Best regards
Thomas

> +
>   /**
>    * DOC: cma helpers
>    *

-- 
Thomas Zimmermann
Graphics Driver Developer
SUSE Software Solutions Germany GmbH
Maxfeldstr. 5, 90409 Nürnberg, Germany
(HRB 36809, AG Nürnberg)
Geschäftsführer: Felix Imendörffer