[PATCH] drm/i915: Allow NULL memory region

[Nirmoy Das]

On 7/12/2024 11:41 PM, Jonathan Cavitt wrote:
> Prevent a NULL pointer access in intel_memory_regions_hw_probe.
>
> Fixes: 05da7d9f717b ("drm/i915/gem: Downgrade stolen lmem setup warning")
> Reported-by: Dan Carpenter <dan.carpenter at linaro.org>
> Signed-off-by: Jonathan Cavitt <jonathan.cavitt at intel.com>
> ---
>   drivers/gpu/drm/i915/intel_memory_region.c | 6 ++++--
>   1 file changed, 4 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/intel_memory_region.c b/drivers/gpu/drm/i915/intel_memory_region.c
> index 172dfa7c3588b..d40ee1b42110a 100644
> --- a/drivers/gpu/drm/i915/intel_memory_region.c
> +++ b/drivers/gpu/drm/i915/intel_memory_region.c
> @@ -368,8 +368,10 @@ int intel_memory_regions_hw_probe(struct drm_i915_private *i915)
>   			goto out_cleanup;
>   		}
>   
> -		mem->id = i;
> -		i915->mm.regions[i] = mem;

There is a check for mem just before that. You could use 
IS_ERR_OR_NULL(mem) instead of IS_ERR().


Regards,

Nirmoy

> +		if (mem) { /* Skip on non-fatal errors */
> +			mem->id = i;
> +			i915->mm.regions[i] = mem;
> +		}
>   	}
>   
>   	for (i = 0; i < ARRAY_SIZE(i915->mm.regions); i++) {