Re: Strange memory problem with Linux booted from U-Boot

["Ara Avanesyan" <araav@hylink.am>]

----- Original Message ----- 
From: "Jan Engelhardt" <jengelh@linux01.gwdg.de>
To: "Ara Avanesyan" <araav@hylink.am>
Cc: <linux-kernel@vger.kernel.org>; <avila@lists.unixstudios.net>
Sent: Monday, March 28, 2005 8:06 PM
Subject: Re: Strange memory problem with Linux booted from U-Boot


> >Hi,
> >
> >I need some help on solving this strange problem.
> >Here is what I have,
> >I have a loadable module (linux.2.4.20) which contains a 2 mb static
gloabal
> >array.
> >
> >Additional information:
> >The same error occurs if I just run depmod -a.
>
> I'd be more interested in the kernel space code...
>
>
>
> Jan Engelhardt
> -- 
> No TOFU for me, please.
>

Oh, the code for kernel space is exactly the same code translated to C:
That is:

___________
#include <linux/vmalloc.h>

void mtestit(char val)
{
    char *buf;
    int i, j;
    int size = 64;
    int pass = 2 * 1024 * 1024;
    printk("starting val == %x\n", val);
    buf = vmalloc(size);
    printk("allocated memory of %d bytes. buf == %x\n", size, (int)buf);

    for (j = 0; j < pass; j++)
    {
        printk("passing %d", j);
        for (i = 0; i < size; i++)
        {
            buf[i] = val;
        }
        printk("passed\n");
    }

    printk("freeing\n");
    vfree(buf);
    printk("finished!\n");
}
___________

I call this in a module's entry point and insmod that module.
now, mtestit(0xff) works, but mtestit(0x00) crashes:(
Works fine with RedBoot. Very strange to me:)
Moreover, works fine if I do the very same thing from
within U-Boot (mw.b 100000 0 100000).

I'm interested in ideas of what could potentially be the
cause of this strange behaviour.

__
Thanks,
Ara