Re: [PATCH 1/2] riscv: Add memmove string operation.

From: Nick Hu
Date: Tue Aug 27 2019 - 05:08:56 EST


Hi Andrey

On Thu, Aug 22, 2019 at 11:59:02PM +0800, Andrey Ryabinin wrote:
> On 8/7/19 10:19 AM, Nick Hu wrote:
> > There are some features which need this string operation for compilation,
> > like KASAN. So the purpose of this porting is for the features like KASAN
> > which cannot be compiled without it.
> >
>
> Compilation error can be fixed by diff bellow (I didn't test it).
> If you don't need memmove very early (before kasan_early_init()) than arch-specific not-instrumented memmove()
> isn't necessary to have.
>
> ---
> mm/kasan/common.c | 2 ++
> 1 file changed, 2 insertions(+)
>
> diff --git a/mm/kasan/common.c b/mm/kasan/common.c
> index 6814d6d6a023..897f9520bab3 100644
> --- a/mm/kasan/common.c
> +++ b/mm/kasan/common.c
> @@ -107,6 +107,7 @@ void *memset(void *addr, int c, size_t len)
> return __memset(addr, c, len);
> }
>
> +#ifdef __HAVE_ARCH_MEMMOVE
> #undef memmove
> void *memmove(void *dest, const void *src, size_t len)
> {
> @@ -115,6 +116,7 @@ void *memmove(void *dest, const void *src, size_t len)
>
> return __memmove(dest, src, len);
> }
> +#endif
>
> #undef memcpy
> void *memcpy(void *dest, const void *src, size_t len)
> --
> 2.21.0
>
>
>
I have confirmed that the string operations are not used before kasan_early_init().
But I can't make sure whether other ARCHs would need it before kasan_early_init().
Do you have any idea to check that? Should I cc all other ARCH maintainers?

Nick