Re: [PATCH 1/4] kasan: mark addr_has_metadata __always_inline

[Marco Elver <elver@google.com>]

On Wed, 8 Feb 2023 at 17:40, Arnd Bergmann <arnd@kernel.org> wrote:
>
> From: Arnd Bergmann <arnd@arndb.de>
>
> When the compiler decides not to inline this function, objdump
> complains about incorrect UACCESS state:
>
> mm/kasan/generic.o: warning: objtool: __asan_load2+0x11: call to addr_has_metadata() with UACCESS enabled
>
> Signed-off-by: Arnd Bergmann <arnd@arndb.de>

Reviewed-by: Marco Elver <elver@google.com>

> ---
>  mm/kasan/kasan.h | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/mm/kasan/kasan.h b/mm/kasan/kasan.h
> index 3231314e071f..9377b0789edc 100644
> --- a/mm/kasan/kasan.h
> +++ b/mm/kasan/kasan.h
> @@ -297,7 +297,7 @@ static inline const void *kasan_shadow_to_mem(const void *shadow_addr)
>                 << KASAN_SHADOW_SCALE_SHIFT);
>  }
>
> -static inline bool addr_has_metadata(const void *addr)
> +static __always_inline bool addr_has_metadata(const void *addr)
>  {
>         return (kasan_reset_tag(addr) >=
>                 kasan_shadow_to_mem((void *)KASAN_SHADOW_START));
> @@ -316,7 +316,7 @@ bool kasan_check_range(unsigned long addr, size_t size, bool write,
>
>  #else /* CONFIG_KASAN_GENERIC || CONFIG_KASAN_SW_TAGS */
>
> -static inline bool addr_has_metadata(const void *addr)
> +static __always_inline bool addr_has_metadata(const void *addr)
>  {
>         return (is_vmalloc_addr(addr) || virt_addr_valid(addr));
>  }
> --
> 2.39.1
>