Date: Mon, 1 Sep 2008 21:47:26 +0200 From: Marius Strobl <marius@alchemy.franken.de> To: Gavin Atkinson <gavin@FreeBSD.org> Cc: gibbs@FreeBSD.org, freebsd-sparc64@FreeBSD.org Subject: Re: HEAD panic with ofw_pcibus.c 1.21 on Blade 100 Message-ID: <20080901194726.GG80839@alchemy.franken.de> In-Reply-To: <1220287328.70590.46.camel@buffy.york.ac.uk> References: <1220278827.70590.35.camel@buffy.york.ac.uk> <20080901161850.GE80839@alchemy.franken.de> <1220287328.70590.46.camel@buffy.york.ac.uk>
next in thread | previous in thread | raw e-mail | index | archive | help
On Mon, Sep 01, 2008 at 05:42:08PM +0100, Gavin Atkinson wrote:
> On Mon, 2008-09-01 at 18:18 +0200, Marius Strobl wrote:
> > On Mon, Sep 01, 2008 at 03:20:27PM +0100, Gavin Atkinson wrote:
> > > Hi all,
> > >
> > > My Blade 100 now panics on boot with HEAD, and I've tracked it down to
> > > sys/sparc64/pci/ofw_pcibus.c 1.21 (SVN r182108) by marius@.
>
> > The most likely reason for this is a buggy driver. In this
> > case the culprit appears to be the ISA front-end of ahc(4),
> > which assumes that it can do bus space reads and writes at
> > addresses that may in fact be assigned to a non-ahc(4)-
> > compatible device or none at all. While writing something
> > at an address that may no belong to the expected device
> > probably is a bad idea in generally, reading to and writing
> > from unassigned addresses may also trigger exceptions on
> > sparc64. I'm unsure how to really fix ahc(4) regarding this,
> > I think it should be okay though to only do it on i386 where
> > the address range in question probably is reserved for such
> > purposes (and which also is the only architecture FreeBSD
> > currently runs on where a machine might have an ISA-slot
> > and thus can use that front-end at all).
> > Justin, do you approve the below patch?
> >
> > Marius
> >
> > Index: ahc_isa.c
> > ===================================================================
> > --- ahc_isa.c (revision 182474)
> > +++ ahc_isa.c (working copy)
> > @@ -82,6 +82,12 @@ ahc_isa_identify(driver_t *driver, device_t parent
> > int slot;
> > int max_slot;
> >
> > +#if !defined(__i386__)
> > + /*
> > + * Don't assume we can get away with the blind bus space
> > + * reads and writes which ahc_isa_find_device() does.
> > + */
> > +#endif
> > max_slot = 14;
> > for (slot = 0; slot <= max_slot; slot++) {
> > struct aic7770_identity *entry;
>
> This patch (with the addition of a "return;" inside the #ifdef which I'm
> assuming was forgotten!) gets me booting again with stock ofw_pcibus.c.
Oops, the "return;" was missing of course.
Marius
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20080901194726.GG80839>