Re: [PATCH v3 04/13] x86: Handle KCOV __init vs inline mismatches

From: Mike Rapoport <rppt@kernel.org>
To: Kees Cook <kees@kernel.org>
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Subject: Re: [PATCH v3 04/13] x86: Handle KCOV __init vs inline mismatches
Date: Fri, 18 Jul 2025 11:36:32 +0300	[thread overview]
Message-ID: <aHoHkDvvp4AHIzU1@kernel.org> (raw)
In-Reply-To: <20250717232519.2984886-4-kees@kernel.org>

Hi Kees,

On Thu, Jul 17, 2025 at 04:25:09PM -0700, Kees Cook wrote:
> When KCOV is enabled all functions get instrumented, unless the
> __no_sanitize_coverage attribute is used. To prepare for
> __no_sanitize_coverage being applied to __init functions, we have to
> handle differences in how GCC's inline optimizations get resolved. For
> x86 this means forcing several functions to be inline with
> __always_inline.
> 
> Signed-off-by: Kees Cook <kees@kernel.org>

...

> diff --git a/include/linux/memblock.h b/include/linux/memblock.h
> index bb19a2534224..b96746376e17 100644
> --- a/include/linux/memblock.h
> +++ b/include/linux/memblock.h
> @@ -463,7 +463,7 @@ static inline void *memblock_alloc_raw(phys_addr_t size,
>  					  NUMA_NO_NODE);
>  }
>  
> -static inline void *memblock_alloc_from(phys_addr_t size,
> +static __always_inline void *memblock_alloc_from(phys_addr_t size,
>  						phys_addr_t align,
>  						phys_addr_t min_addr)

I'm curious why from all memblock_alloc* wrappers this is the only one that
needs to be __always_inline?

-- 
Sincerely yours,
Mike.