Re: objtool warning from next-20230125

From: Josh Poimboeuf
Date: Thu Jan 26 2023 - 16:00:01 EST


On Thu, Jan 26, 2023 at 10:23:02AM -0800, Paul E. McKenney wrote:
> Hello!
>
> I have started seeing these objtool warnings from a wide variety of
> KASAN-enabled rcutorture-related test scenarios in next-20230125. It has
> been awhile since I tested -next, so I am not yet sure where this started.
>
> vmlinux.o: warning: objtool: __asan_memset+0x34: call to __memset() with UACCESS enabled
> vmlinux.o: warning: objtool: __asan_memmove+0x4d: call to __memmove() with UACCESS enabled
> vmlinux.o: warning: objtool: __asan_memcpy+0x4d: call to __memcpy() with UACCESS enabled
>
> As usual, should I be worried?

This apparently came from Peter's

69d4c0d32186 ("entry, kasan, x86: Disallow overriding mem*() functions")

but I have no idea how this is supposed to work. Peter?

--
Josh