Re: [PATCH v3 5/6] powerpc/fsl_booke/64: clear the original kernel if randomized

[Jason Yan]

å 2020/2/20 21:49, Christophe Leroy åé:
> Le 06/02/2020 Ã 03:58, Jason Yan a ÃcritÂ:
> > The original kernel still exists in the memory, clear it now.
>
> No such problem with PPC32 ? Or is that common ?

PPC32 did this in relocate_init() in fsl_booke.c because PPC32 will not 
reach kaslr_early_init for the second pass after relocation.

Thanks,
Jason

> Christophe
>
> > Signed-off-by: Jason Yan <yanaijie@xxxxxxxxxx>
> > Cc: Scott Wood <oss@xxxxxxxxxxxx>
> > Cc: Diana Craciun <diana.craciun@xxxxxxx>
> > Cc: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
> > Cc: Christophe Leroy <christophe.leroy@xxxxxx>
> > Cc: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx>
> > Cc: Paul Mackerras <paulus@xxxxxxxxx>
> > Cc: Nicholas Piggin <npiggin@xxxxxxxxx>
> > Cc: Kees Cook <keescook@xxxxxxxxxxxx>
> > ---
> > Â arch/powerpc/mm/nohash/kaslr_booke.c | 4 +++-
> > Â 1 file changed, 3 insertions(+), 1 deletion(-)
> >
> > diff --git a/arch/powerpc/mm/nohash/kaslr_booke.c 
> > b/arch/powerpc/mm/nohash/kaslr_booke.c
> > index c6f5c1db1394..ed1277059368 100644
> > --- a/arch/powerpc/mm/nohash/kaslr_booke.c
> > +++ b/arch/powerpc/mm/nohash/kaslr_booke.c
> > @@ -378,8 +378,10 @@ notrace void __init kaslr_early_init(void 
> > *dt_ptr, phys_addr_t size)
> > ÂÂÂÂÂ unsigned int *__kaslr_offset = (unsigned int *)(KERNELBASE + 0x58);
> > ÂÂÂÂÂ unsigned int *__run_at_load = (unsigned int *)(KERNELBASE + 0x5c);
> > -ÂÂÂ if (*__run_at_load == 1)
> > +ÂÂÂ if (*__run_at_load == 1) {
> > +ÂÂÂÂÂÂÂ kaslr_late_init();
> > ÂÂÂÂÂÂÂÂÂ return;
> > +ÂÂÂ }
> > ÂÂÂÂÂ /* Setup flat device-tree pointer */
> > ÂÂÂÂÂ initial_boot_params = dt_ptr;
>
> .