On Fri, 2010-04-16 at 00:00 +0200, Gilles DOFFE wrote:
> Hello,
>
> I try to install a real-time Linux kernel on a Roboard based on a
> Vortex86DX (a x486 with TSC).
>
> All works fine with :
> Linux Kernel 2.6.30.10
> Xenomai 2.5.1
> Adeos patch adeos-ipipe-2.6.30.8-x86-2.4-09.patch
>
> But, for all kernels upper or equal to 2.6.31, I always get a double
> fault when testing WP bit. I have this double fault just after that :
>
> Checking if this processor honours the WP bit even in supervisor
> mode...
>
> I traced with some simple printk that the problem occurs in this
> function, at the end or after the call of fix_to_virt :
>
> static noinline int do_test_wp_bit(void)
> {
> char tmp_reg;
> int flag;
>
> __asm__ __volatile__(
> " movb %0, %1 \n"
> "1: movb %1, %0 \n"
> " xorl %2, %2 \n"
> "2: \n"
> _ASM_EXTABLE(1b,2b)
> :"=m" (*(char *)fix_to_virt(FIX_WP_TEST)),
> "=q" (tmp_reg),
> "=r" (flag)
> :"2" (1)
> :"memory");
>
> return flag;
> }
>
> I'm (quasi) sure that the problem is not that function, due to it
> works when the kernel is not patched.
> But where should I search ?
Try backporting these two 2.6.32 patches to your kernel; this should be
straightforward:
http://git.denx.de/?p=ipipe-2.6.git;a=commit;h=576f57f82dfd6c3ac285b0af76e5e0ce617679ba
http://git.denx.de/?p=ipipe-2.6.git;a=commit;h=a250e984a76fd327a0d8cfada5290b27e99f1e4d
>
> Can you give me some indications ?
>
> Thanks,
> Gilles
> _______________________________________________
> Adeos-main mailing list
> [email protected]
> https://mail.gna.org/listinfo/adeos-main
--
Philippe.
_______________________________________________
Adeos-main mailing list
[email protected]
https://mail.gna.org/listinfo/adeos-main
