Re: [PATCH v1 1/2] mm/execmem: Print size, align and caller on allocation failure

[Andrew Morton]

On Fri, 17 Jul 2026 15:57:14 +0800 Tiezhu Yang <yangtiezhu@xxxxxxxxxxx> wrote:

> The current execmem_vmalloc() function reports an allocation failure
> with a simplistic "unable to allocate memory" message. This notifies
> the user that an error occurred, but it acts as a black box during
> debugging.
> 
> Enhance pr_warn_ratelimited() within execmem_vmalloc() to explicitly
> print the requested allocation size, alignment constraints, and the
> symbolic caller.
> 
> This diagnostic visibility is valuable for analyzing the root cause
> of allocation failures and tracking misbehaving subsystems without
> inducing log pollution.

Have you actually encountered this?  GFP_KERNEL allocation failures are
supposed to be very rare.

> ...
>
> --- a/mm/execmem.c
> +++ b/mm/execmem.c
> @@ -50,7 +50,9 @@ static void *execmem_vmalloc(struct execmem_range *range, size_t size,
>  	}
>  
>  	if (!p) {
> -		pr_warn_ratelimited("unable to allocate memory\n");
> +		pr_warn_ratelimited("unable to allocate memory, "
> +				    "size=%zu, align=%u, caller is %pS\n",
> +				     size, align, __builtin_return_address(0));
>  		return NULL;
>  	}

This seems to be duplicating the information which the page allocator
can emit.  Perhaps we should remove the __GFP_NOWARN in there?