Dear Gilles,

I admit, the mechanism for allocating all memory of the target is not very 
sophisticated. The idea was, that MAXHEAPBLOCKS*MEMORYCHUNKSIZE is much much 
more, than memory available (at least with my target (128MB) this is true). I 
should have mentioned this in the source code, sorry. If your target has more 
then (MAXHEAPBLOCKS*MEMORYCHUNKSIZE=320MB(approcimate)) memory, you should 
increase MAXHEAPBLOCKS.

If this condition is fulfiled, I think, there should be no illegal memory 
access. Do you agree ?

Roderik
 

> -----Ursprüngliche Nachricht-----
> Von: Gilles Chanteperdrix [mailto:[EMAIL PROTECTED] 
> Gesendet: Dienstag, 5. September 2006 17:18
> An: Wildenburg, Roderik RAEK3 MRA
> Cc: [email protected]
> Betreff: Re: [Xenomai-help] resubmission : memset of heap 
> crashes Xenomai-Task
> 
> [EMAIL PROTECTED] wrote:
>  > Some times ago (2006.07.06) I had the problem described below. 
>  > As far as I can see, there is no solution for this till now. 
>  > I think, it is worth a second go, as I believe, a 
> industrial strength application can´t accept this behavior.
>  > Therefore I would like to ask the Xenomai-PPC gurus (as 
> far as I can see, it could only be reproduced on PPC (not 
> Qemu)) again, to judge, whether this is a serios problem or 
> just something I have to live with.
>  >
>  > Thank you in advance
>  > Roderik
>  >
>  >
>  > Xenomai Version : 2.2-rc2
>  > Skin : native
>  > Kernel : 2.4.25
>  > Arch.: PPC
>  >
>  > I try to allocate as much memory as possible with the functions :
>  > rt_heap_create and
>  > rt_heap_alloc.
>  > (see source attached)
>  >
>  > When I try to use the allocated memory with memset, the 
> Xenomai-task crashes with a "Segmentation fault".
> 
> You are doing:
> 
> RT_HEAP bigheap[MAXHEAPBLOCKS];
>    
> 
>    for(i=0;i<MAXHEAPBLOCKS;i++)
>    {
>        /* some treatment */
>    }
> 
>    /* access bigheap[i] */
> 
> After the for loop, i is MAXHEAPBLOCKS, so, you are accessing 
> the bigheap array beyond its end, probably overriding the 
> bigbuf array.
> 
> -- 
> 
> 
>                                           Gilles Chanteperdrix.
> 

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