Re: [PATCH 3/3] tracing: Fix simple_ring_buffer undef check on sparc64

[Guenter Roeck <linux@roeck-us.net>]

On Wed, Sep 23, 2026 at 08:42:13AM +0100, Vincent Donnefort wrote:
> simple_ring_buffer relies on headers that end up including
> <asm/thread_info.h>. On sparc64, this emits the undefined symbol
> current_thread_info_reg. Allow this symbol.
> 
> Fixes: 1211907ac0b5 ("tracing: Generate undef symbols allowlist for simple_ring_buffer")
> Reported-by: Guenter Roeck <linux@roeck-us.net>
> Closes: https://lore.kernel.org/all/5574c9e6-9ed2-4ee6-a2b2-fb6ee81e83a1@roeck-us.net/
> Signed-off-by: Vincent Donnefort <vdonnefort@google.com>

Tested-by: Guenter Roeck <linux@roeck-us.net>

> ---
>  kernel/trace/Makefile | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/kernel/trace/Makefile b/kernel/trace/Makefile
> index 0e1846f7dda3..3860bc53a4be 100644
> --- a/kernel/trace/Makefile
> +++ b/kernel/trace/Makefile
> @@ -146,6 +146,7 @@ KASAN_SANITIZE_undefsyms_base.o := y
>  
>  UNDEFINED_ALLOWLIST = __asan __gcov __kasan __kcsan __hwasan __sancov __sanitizer __tsan __ubsan __msan \
>  		      __aeabi_unwind_cpp __s390_indirect_jump __x86_indirect_thunk simple_ring_buffer \
> +		      current_thread_info_reg \
>  		      $(shell $(NM) -u $(obj)/undefsyms_base.o 2>/dev/null | awk '$$2 {print $$2}')
>  
>  quiet_cmd_check_undefined = NM      $<
> -- 
> 2.55.0.1082.g2b9226bbc0-goog
>