Re: [PATCH 1/2] drm/i915: set O_LARGEFILE in __create_shmem()

[Andi Shyti]

Hi Taotao,

> Reported-by: kernel test robot <oliver.sang@xxxxxxxxx>
> Closes: https://lore.kernel.org/oe-lkp/202508081029.343192ec-lkp@xxxxxxxxx

...

> diff --git a/drivers/gpu/drm/i915/gem/i915_gem_shmem.c b/drivers/gpu/drm/i915/gem/i915_gem_shmem.c
> index e3d188455f67..2b53aad915f5 100644
> --- a/drivers/gpu/drm/i915/gem/i915_gem_shmem.c
> +++ b/drivers/gpu/drm/i915/gem/i915_gem_shmem.c
> @@ -514,6 +514,11 @@ static int __create_shmem(struct drm_i915_private *i915,
>  	if (IS_ERR(filp))
>  		return PTR_ERR(filp);
>  
> +	/*
> +	 * Prevent -EFBIG by allowing large writes beyond MAX_NON_LFS on shmem
> +	 * objects by setting O_LARGEFILE.
> +	 */
> +	filp->f_flags |= O_LARGEFILE;

I don't have anything against this, but is it really fixing the
issue? I thought that O_LARGEFILE is ignored in 64 bit machines,
while here the failure is happening in 64 bit machines.

Besides, where do you see in the LKP logs the -EFBIG error
message?

Andi

>  	obj->filp = filp;
>  	return 0;
>  }
> -- 
> 2.34.1