lkml.org 
[lkml]   [2003]   [Nov]   [20]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
From
SubjectRe: [PATCH][2.6-mm] Fix 4G/4G X11/vm86 oops
On Wed, Nov 19, 2003 at 05:09:28PM -0600, Matt Mackall wrote:
> On Wed, Nov 19, 2003 at 02:32:10PM -0600, Matt Mackall wrote:
> >
> > Zwane's got a K6-2 500MHz. I've just managed to reproduce this on my
> > 1.4GHz Opteron box (with Debian gcc 3.2). Here, the "ooh la la" bit
> > doesn't help. So my suspicion is that the printk is changing the
> > timing just enough on Zwane's box that he's getting a timer interrupt
> > knocking him out of vm86 mode before he hits a fatal bit in the fault
> > handling path for 4/4. Printks in handle_vm86_trap, handle_vm86_fault,
> > do_trap:vm86_trap, and do_general_protection:gp_in_vm86 never fire so
> > there's probably something amiss in the trampoline code.
>
> Some more datapoints:
>
> CPU distro compiler video X result
> K6-2/500 connectiva 9 2.96 trident 4.3 reboot (zwane)
> K6-2/500 connectiva 9 3.2.2 trident 4.3 reboot (zwane)
> Opteron 240 debian unstable 3.2 S3 4.2.1 reboot
> Athlon 2100 debian unstable 3.2 radeon 7500 4.2.1 works
> P4M 1800 debian unstable 3.2 radeon m7 4.2.1 reboot

And indeed it does turn out to be a problem with the trampoline
mechanics. The fix for -mm4:


Fix triple faulting on some boxes with 4G/4G


mm-mpm/arch/i386/kernel/vm86.c | 2 +-
1 files changed, 1 insertion(+), 1 deletion(-)
diff -puN arch/i386/kernel/vm86.c~virtual-esp arch/i386/kernel/vm86.c
--- mm/arch/i386/kernel/vm86.c~virtual-esp 2003-11-20 01:36:32.000000000 -0600
+++ mm-mpm/arch/i386/kernel/vm86.c 2003-11-20 01:36:32.000000000 -0600
@@ -306,7 +306,7 @@ static void do_sys_vm86(struct kernel_vm
tss->esp0 = virtual_esp0(tsk);
if (cpu_has_sep)
tsk->thread.sysenter_cs = 0;
- load_esp0(tss, &tsk->thread);
+ load_virtual_esp0(tss, tsk);
put_cpu();

tsk->thread.screen_bitmap = info->screen_bitmap;
_


--
Matt Mackall : http://www.selenic.com : Linux development and consulting
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2005-03-22 13:58    [from the cache]
©2003-2011 Jasper Spaans