Date: Wed, 21 Nov 2012 11:48:41 +0100 From: Stefan Farfeleder <stefanf@FreeBSD.org> To: Andriy Gapon <avg@FreeBSD.org> Cc: freebsd-acpi@FreeBSD.org Subject: Re: ACPI panic Message-ID: <20121121104840.GA1468@mole.fafoe.narf.at> In-Reply-To: <50AC0A68.8070906@FreeBSD.org> References: <20121120103522.GB2012@mole.fafoe.narf.at> <50AC0A68.8070906@FreeBSD.org>
next in thread | previous in thread | raw e-mail | index | archive | help
On Wed, Nov 21, 2012 at 12:55:36AM +0200, Andriy Gapon wrote:
> on 20/11/2012 12:35 Stefan Farfeleder said the following:
> > Hi,
> >
> > today I got the following panic on booting. The error seems to be some
> > kind of race condition, as the same kernel booted fine before and
> > afterwards. This is current, r243234.
> >
> > Any additional information required to debug/fix this?
> [snip]
>
> This indeed looks like a heisenbug that happens to FreeBSD users now and then
> (google for AcpiOsAcquireObject panic).
> I am trying a verify a certain theory... just on the chance that this issue
> happens again, could you please try the following debugging patch?
>
> Index: sys/contrib/dev/acpica/components/utilities/utdelete.c
> ===================================================================
> --- sys/contrib/dev/acpica/components/utilities/utdelete.c (revision 243265)
> +++ sys/contrib/dev/acpica/components/utilities/utdelete.c (working copy)
> @@ -441,7 +441,7 @@
> "Obj %p Refs=%X, can't decrement! (Set to 0)\n",
> Object, NewCount));
>
> - NewCount = 0;
> + NewCount = *(volatile UINT16*)NULL;
> }
> else
> {
>
>
> I hope that this compiles. The point is to induce a panic sooner rather than later.
Thanks. I've applied this and will report back if it triggers a panic.
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20121121104840.GA1468>