Re: ofppc - panic pmap_pvo_find_va returning NULL for kernel pmap

[Rin Okuyama <rokuyama.rk%gmail.com@localhost>]

Hi Radoslaw,

On 2026/07/01 2:27, Radoslaw Kujawa wrote:
> Hi list.
>
> On 6/30/26 00:40, Radosław Kujawa wrote:
>
> > The check should not assume that given VA >= PMAP_DIRECT_MAPPED_LEN . 
> > Note that PMAP_DIRECT_MAPPED_LEN is calculated according to the 
> > formula in oea/pmap.h (line 128) :
> >
> > SEGMENT_LENGTH (256MB) * USER_SR
> >
> > Why does the panic not trigger on macppc and other PowerPC ports? By 
> > coincidence that depends on ordering of USER_SR and KERNEL_SR utilized 
> > by a given port:
> >
> > macppc, evbppc etc. use USER_SR 12 and KERNEL_SR 13, 14, so segment- 
> > mappend KVA lands between 0xD0000000 - 0xF0000000, and 
> > PMAP_DIRECT_MAPPED_LEN as calculated is 0xC0000000 .
> > ofppc uses USER_SR 14 and KERNEL_SR 10, 11, so segment-mapped KVA 
> > lands between 0xA0000000 - 0xC0000000, and PMAP_DIRECT_MAPPED_LEN as 
> > calculated is 0xE0000000 .
>
> After discussion with other developers (thanks Martin, Nick), it was 
> concluded that cleanest solution is to fix the PMAP_DIRECT_MAPPED_LEN 
> calculation itself, so that PMAP_DIRECT_MAPPED_LEN reflects true range 
> of identity-mapped addresses and is independent of KERNEL_SR / USER_SR 
> ordering on a given port.
>
> The following fix was committed today.

Thank you very much for fixing my overlook for ofppc!

Can you please pull up this fix to netbsd-{10,11}, or can I?

Thanks,
rin