[PATCH] drm/nouveau: avoid null deref on bad arguments to nouveau_vma_getmap

[Pasi Kärkkäinen]

On Wed, Sep 04, 2013 at 08:59:13AM +0200, Maarten Lankhorst wrote:
> 
> When looking into this bug I noticed that nouveau_bo_vma_add needs to have a check for nvbo->page_shift == vma->vm->vmm->spg_shift,
> and only if the check is true it should map the page in TTM_PL_TT. Patch below.
> Should probably also be cc'd to stable.
>

How about this patch? Is it ready to go in? 

Thanks,

-- Pasi

 
> ~Maarten
> 
> diff --git a/drivers/gpu/drm/nouveau/nouveau_bo.c b/drivers/gpu/drm/nouveau/nouveau_bo.c
> index 89b992e..355a1b7 100644
> --- a/drivers/gpu/drm/nouveau/nouveau_bo.c
> +++ b/drivers/gpu/drm/nouveau/nouveau_bo.c
> @@ -1560,7 +1560,8 @@ nouveau_bo_vma_add(struct nouveau_bo *nvbo, struct nouveau_vm *vm,
>  
>  	if (nvbo->bo.mem.mem_type == TTM_PL_VRAM)
>  		nouveau_vm_map(vma, nvbo->bo.mem.mm_node);
> -	else if (nvbo->bo.mem.mem_type == TTM_PL_TT) {
> +	else if (nvbo->bo.mem.mem_type == TTM_PL_TT &&
> +		 nvbo->page_shift == vma->vm->vmm->spg_shift) {
>  		if (node->sg)
>  			nouveau_vm_map_sg_table(vma, 0, size, node);
>  		else
>