lkml.org 
[lkml]   [2021]   [Sep]   [18]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
From
SubjectRe: [PATCH] Fix the bool convert to int issue
On Sat, Sep 18, 2021 at 07:30:37AM +0000, cgel.zte@gmail.com wrote:
> From: Yang Guang <yang.guang5@zte.com.cn>
>
> The int value which convert from bool true is 0xFFFFFFFF. Causing the
> __sc_insn return wrong type.

Aaah, this is where the insanity starts...

My copy of the C spec says:

"When any scalar value is converted to _Bool, the result is 0 if the
value compares equal to 0; otherwise, the result is 1."

What does yours say?

Also, did your kernel boot? If what you say is right it would've gone up
in flames a long time ago.

Please, learn C _before_ sending patches.

*plonk*

>
> Signed-off-by: Yang Guang <yang.guang5@zte.com.cn>
> ---
> arch/x86/kernel/static_call.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/arch/x86/kernel/static_call.c b/arch/x86/kernel/static_call.c
> index ea028e736831..f608e6710300 100644
> --- a/arch/x86/kernel/static_call.c
> +++ b/arch/x86/kernel/static_call.c
> @@ -89,7 +89,7 @@ static inline enum insn_type __sc_insn(bool null, bool tail)
> * 1 | 0 | JMP
> * 1 | 1 | RET
> */
> - return 2*tail + null;
> + return ((tail)?2:0) + ((null)?1:0);
> }
>
> void arch_static_call_transform(void *site, void *tramp, void *func, bool tail)
> --
> 2.25.1
>

\
 
 \ /
  Last update: 2021-09-18 10:21    [W:0.102 / U:0.124 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site