Re: [PATCH v3 09/19] unwind: Introduce sframe user space unwinding

[Jens Remus <jremus@linux.ibm.com>]

On 13.11.2024 23:13, Steven Rostedt wrote:
> On Wed, 13 Nov 2024 13:15:35 -0800

> BTW, the following changes were needed to make it work for me:

> diff --git a/kernel/unwind/sframe.c b/kernel/unwind/sframe.c
> index 933e47696e29..ca4ef0b72772 100644
> --- a/kernel/unwind/sframe.c
> +++ b/kernel/unwind/sframe.c
> @@ -73,15 +73,15 @@ static int find_fde(struct sframe_section *sec, unsigned long ip,
>   		    struct sframe_fde *fde)
>   {
>   	struct sframe_fde __user *first, *last, *found = NULL;
> -	u32 ip_off, func_off_low = 0, func_off_high = -1;
> +	s32 ip_off, func_off_low = INT_MIN, func_off_high = INT_MAX;

Coincidentally I was experimenting with exactly the same changes, except 
that I used S32_MIN and S32_MAX.  Any preference?

>   
>   	ip_off = ip - sec->sframe_addr;
>   
>   	first = (void __user *)sec->fdes_addr;
> -	last = first + sec->fdes_nr;
> +	last = first + sec->fdes_nr - 1;
>   	while (first <= last) {
>   		struct sframe_fde __user *mid;
> -		u32 func_off;
> +		s32 func_off;
>   
>   		mid = first + ((last - first) / 2);
>   

Thanks and regards,
Jens
-- 
Jens Remus
Linux on Z Development (D3303) and z/VSE Support
+49-7031-16-1128 Office
jremus@de.ibm.com

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