Subject: Re: linux-next: build failure after merge of the drm-misc tree

From: Felix Kuehling <[email-masked]>
Date: Tue, 8 Jun 2021 01:37:45 -0400

Hi Christian,

I based amdgpu_preempt_mgr on amdgpu_gtt_mgr and now I'm looking at what
changed there. Looks like I'll need to create a dummy node in
amdgpu_preempt_mgr_new to satisfy TTM, and free it in
amdgpu_preempt_mgr_del.

Thanks,
  Felix

Am 2021-06-07 um 10:50 p.m. schrieb Stephen Rothwell:
> Hi all,
>
> After merging the drm-misc tree, today's linux-next build (x86_64
> allmodconfig) failed like this:
>
> drivers/gpu/drm/amd/amdgpu/amdgpu_preempt_mgr.c: In function 'amdgpu_preempt_mgr_new':
> drivers/gpu/drm/amd/amdgpu/amdgpu_preempt_mgr.c:75:5: error: 'struct ttm_resource' has no member named 'mm_node'
>    75 |  mem->mm_node = NULL;
>       |     ^~
> drivers/gpu/drm/amd/amdgpu/amdgpu_preempt_mgr.c: At top level:
> drivers/gpu/drm/amd/amdgpu/amdgpu_preempt_mgr.c:129:11: error: initialization of 'int (*)(struct ttm_resource_manager *, struct ttm_buffer_object *, const struct ttm_place *, struct ttm_resource **)' from incompatible pointer type 'int (*)(struct ttm_resource_manager *, struct ttm_buffer_object *, const struct ttm_place *, struct ttm_resource *)' [-Werror=incompatible-pointer-types]
>   129 |  .alloc = amdgpu_preempt_mgr_new,
>       |           ^~~~~~~~~~~~~~~~~~~~~~
> drivers/gpu/drm/amd/amdgpu/amdgpu_preempt_mgr.c:129:11: note: (near initialization for 'amdgpu_preempt_mgr_func.alloc')
>
> Caused by commit
>
>   cb1c81467af3 ("drm/ttm: flip the switch for driver allocated resources v2")
>
> from the drm-misc tree interacting with commit
>
>   b453e42a6e8b ("drm/amdgpu: Add new placement for preemptible SG BOs")
>
> from the drm tree.
>
> I don't know how to fix this, so I added the following hack (a better
> fix would be nice):
>
> From: Stephen Rothwell <[email-masked]>
> Date: Tue, 8 Jun 2021 12:41:16 +1000
> Subject: [PATCH] hack fix up for needed amdgpu_preempt_mgr_new() fix up
>
> Signed-off-by: Stephen Rothwell <[email-masked]>
> ---
>  drivers/gpu/drm/amd/amdgpu/amdgpu_preempt_mgr.c | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_preempt_mgr.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_preempt_mgr.c
> index d607f314cc1b..e1a7b3e967b9 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_preempt_mgr.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_preempt_mgr.c
> @@ -66,14 +66,16 @@ static DEVICE_ATTR_RO(mem_info_preempt_used);
>  static int amdgpu_preempt_mgr_new(struct ttm_resource_manager *man,
>  				  struct ttm_buffer_object *tbo,
>  				  const struct ttm_place *place,
> -				  struct ttm_resource *mem)
> +				  struct ttm_resource **res)
>  {
> +#if 0
>  	struct amdgpu_preempt_mgr *mgr = to_preempt_mgr(man);
>  
>  	atomic64_add(mem->num_pages, &mgr->used);
>  
>  	mem->mm_node = NULL;
>  	mem->start = AMDGPU_BO_INVALID_OFFSET;
> +#endif
>  	return 0;
>  }
>