Re: [PATCH v9] kallsyms: Add self-test facility

From: Leizhen (ThunderTown)
Date: Fri Dec 16 2022 - 08:31:17 EST




On 2022/12/16 19:57, Andreas Schwab wrote:
> On Dez 16 2022, Leizhen (ThunderTown) wrote:
>
>> It seems that the problem is still strcmp(). After I commented strcmp() in
>> arch/m68k/include/asm/string.h, and force it to use the one in lib/string.c,
>> it works well.
>
> Does that help?

It still needs to add 'volatile' to prevent compiler optimizations.
Otherwise,
Tested-by: Zhen Lei <thunder.leizhen@xxxxxxxxxx>

>
> diff --git a/arch/m68k/include/asm/string.h b/arch/m68k/include/asm/string.h
> index f759d944c449..cdafd67774e0 100644
> --- a/arch/m68k/include/asm/string.h
> +++ b/arch/m68k/include/asm/string.h
> @@ -42,18 +42,19 @@ static inline char *strncpy(char *dest, const char *src, size_t n)
> #define __HAVE_ARCH_STRCMP
> static inline int strcmp(const char *cs, const char *ct)
> {
> - char res;
> + int res = 0, tmp = 0;
>
> asm ("\n"

- asm ("\n"
+ asm volatile ("\n"


> "1: move.b (%0)+,%2\n" /* get *cs */
> - " cmp.b (%1)+,%2\n" /* compare a byte */
> + " move.b (%1)+,%3\n" /* get *ct */
> + " cmp.b %3,%2\n" /* compare a byte */
> " jne 2f\n" /* not equal, break out */
> " tst.b %2\n" /* at end of cs? */
> " jne 1b\n" /* no, keep going */
> " jra 3f\n" /* strings are equal */
> - "2: sub.b -(%1),%2\n" /* *cs - *ct */
> + "2: sub.l %3,%2\n" /* *cs - *ct */
> "3:"
> - : "+a" (cs), "+a" (ct), "=d" (res));
> + : "+a" (cs), "+a" (ct), "+d" (res), "+d" (tmp));
> return res;
> }
> #endif /* CONFIG_COLDFIRE */
>

--
Regards,
Zhen Lei