Re: [rtl] ??? RTLinux on Linux v2.4.2 available for PPC

[Wojciech Kromer <krom@dgt-lab.com.pl>]

> >                 memcpy( (ulong *)KERNELBASE, &block, sizeof(ulong)*7 );
> >
> >                 ^^^ it craches here (memcpy is not allowed to kernel code)
>
> Yes, it is allowed. It's in linux/arch/i386/lib/memcpy.c.

In PPC by default KERNELBASE page is protected. You have to enable KGDB or XMON
to get RW permisions.

from arch/ppc/mm/init.c:

        v = KERNELBASE;
        p = ram_phys_base;
        for (s = 0; s < total_lowmem; s += PAGE_SIZE) {
                /* On the MPC8xx, we want the page shared so we
                 * don't get ASID compares on kernel space.
                 */
                f = _PAGE_PRESENT | _PAGE_ACCESSED | _PAGE_SHARED;
#if defined(CONFIG_KGDB) || defined(CONFIG_XMON)
                /* Allows stub to set breakpoints everywhere */
                f |= _PAGE_RW | _PAGE_DIRTY | _PAGE_HWWRITE;
#else


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