[PATCH 0/8] Fix 8xx MMU/TLB

[Joakim Tjernlund]

Scott Wood <scottwood at freescale.com> wrote on 30/10/2009 01:12:28:
>
> On Sat, Oct 17, 2009 at 02:01:38PM +0200, Joakim Tjernlund wrote:
> > Joakim Tjernlund/Transmode wrote on 17/10/2009 13:24:18:
> > >
> > > Rex Feany <RFeany at mrv.com> wrote on 16/10/2009 22:25:41:
> > > >
> > > > Thus spake Joakim Tjernlund (joakim.tjernlund at transmode.se):
> > > >
> > > > > Right, it is the pte table walk that is blowing up.
> > > > > I just noted that 2.6 lacks a tophys() call in its table walk
> > > > > so I removed that one(there is one more tophys call but I don't think
> > > > > it should be removed).
> > > > > Try this addon patch:
> > > >
> > > > no difference
> >
> > > OK, thinking a bit more, this part should not be executed as
> > > copy_tofrom_user executes in kernel space.
> > >
> > > Any chance you can stick a HW breakpoint on FixupDAR?
> > > Perhaps there is something different with kernel
> > > virtual address to phys address?
> > > A simple topys() works in 2.4, but perhaps not in 2.6?
> > > this is the part of interest:
> > > FixupDAR: /* Entry point for dcbx workaround. */
> > >  /* fetch instruction from memory. */
> > >  mfspr r10, SPRN_SRR0
> > >  andis. r11, r10, 0x8000
> > >  tophys  (r11, r10)
> > >  beq- 139b  /* Branch if user space address */
> > > 140: lwz r11,0(r11)
> >
> > Probably better to walk the kernel page table too. Does this
> > make a difference(needs the tophys() patch I posted earlier):
>
> After applying by hand (whitespace damage), I get this and a bunch more:

OK, please send your diff to head_8xx.S. Maybe I can spot an
error, otherwise you will have to set a hw BP on fixDAR and step
through it.

 Jocke