Re: [PATCH] sun4u: remap ebus BAR0 to use unassigned_io_ops instead of alias to PCI IO space

[Philippe Mathieu-Daudé]

On 11/3/24 09:28, Philippe Mathieu-Daudé wrote:
> On 11/3/24 07:43, Mark Cave-Ayland wrote:
> > During kernel startup OpenBSD accesses addresses mapped by BAR0 of the 
> > ebus device
> > but at offsets where no IO devices exist. Before commit 4aa07e8649 
> > ("hw/sparc64/ebus:
> > Access memory regions via pci_address_space_io()") BAR0 was mapped to 
> > legacy IO
> > space which allows accesses to unmapped devices to succeed, but 
> > afterwards these
> > accesses to unmapped PCI IO space cause a memory fault which prevents 
> > OpenBSD from
> > booting.
> >
> > Since no devices are mapped at the addresses accessed by OpenBSD, 
> > change ebus BAR0
> > from a PCI IO space alias to an IO memory region using 
> > unassigned_io_ops which allows
> > these accesses to succeed and so allows OpenBSD to boot once again.
> >
> > Fixes: 4aa07e8649 ("hw/sparc64/ebus: Access memory regions via 
> > pci_address_space_io()")
> > Signed-off-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
>
> Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
>
> > ---
> >
> > [MCA: I'd like to merge this for 9.0 since I've been carrying various 
> > local workarounds
> > to allow OpenBSD to boot on SPARC64 for some time.]
>
> Sure.

Patch queued!