Re: -tip tree resume fail, bisect to 5bd5a45(x86: Add NX protectionfor kernel data)

From: mat
Date: Fri Nov 26 2010 - 12:31:59 EST


Le Tue, 23 Nov 2010 23:55:27 +0100,
mat <castet.matthieu@xxxxxxx> a écrit :

> Le Mon, 22 Nov 2010 17:42:47 +0100,
> Andi Kleen <andi@xxxxxxxxxxxxxx> a écrit :
>
> > > That seems to be a S3 specific code path, that won't fix anything.
> > > Simply do:
> > >
> > > echo 0 > /sys/devices/system/cpu/cpu1/online;
> > > echo 1 > /sys/devices/system/cpu/cpu1/online;
> > >
> > > and your machine will explode..
> >
> > The SMP startup trampoline is copied I believe
> > and only executed in real mode without page tables.
> >
> > So it's perhaps not the trampoline, but the early startup
> > code that ends up being broken.
> yes :
> acpi wakeup code and smp trampoline are copied in low memory (first
> 1MB).
>
> So they can't end up int the kernel data mapping ?
>
> So it should something else.
>
> I will try to investigate on this.
>
Unfortunately on my laptop supporting NX, suspend to ram seems broken
(even without this patch) and I got only one core, so I am unable to
test it.

Does cpu suspend/resume is broken ? Or it is only S3 ?

If yes, are there any interesting trace if we suspend only one core with
sysfs.

Thanks,

Matthieu
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/