Re: [PATCH v3 0/6] implement KASLR for powerpc/fsl_booke/64

[Jason Yan]

ping...

on 2020/2/13 11:00, Jason Yan wrote:
> Hi everyone, any comments or suggestions?
>
> Thanks,
> Jason
>
> on 2020/2/6 10:58, Jason Yan wrote:
> > This is a try to implement KASLR for Freescale BookE64 which is based on
> > my earlier implementation for Freescale BookE32:
> > https://patchwork.ozlabs.org/project/linuxppc-dev/list/?series=131718
> >
> > The implementation for Freescale BookE64 is similar as BookE32. One
> > difference is that Freescale BookE64 set up a TLB mapping of 1G during
> > booting. Another difference is that ppc64 needs the kernel to be
> > 64K-aligned. So we can randomize the kernel in this 1G mapping and make
> > it 64K-aligned. This can save some code to creat another TLB map at
> > early boot. The disadvantage is that we only have about 1G/64K = 16384
> > slots to put the kernel in.
> >
> > ÂÂÂÂ KERNELBASE
> >
> > ÂÂÂÂÂÂÂÂÂÂ 64KÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ |--> kernel <--|
> > ÂÂÂÂÂÂÂÂÂÂÂ |ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ |ÂÂÂÂÂÂÂÂÂÂÂÂÂ |
> > ÂÂÂÂÂÂÂÂ +--+--+--+ÂÂÂ +--+--+--+--+--+--+--+--+--+ÂÂÂ +--+--+
> > ÂÂÂÂÂÂÂÂ |Â |Â |Â |....|Â |Â |Â |Â |Â |Â |Â |Â |Â |....|Â |Â |
> > ÂÂÂÂÂÂÂÂ +--+--+--+ÂÂÂ +--+--+--+--+--+--+--+--+--+ÂÂÂ +--+--+
> > ÂÂÂÂÂÂÂÂ |ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ |ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ 1G
> > ÂÂÂÂÂÂÂÂ |----->ÂÂ offsetÂÂÂ <-----|
> >
> > ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ kernstart_virt_addr
> >
> > I'm not sure if the slot numbers is enough or the design has any
> > defects. If you have some better ideas, I would be happy to hear that.
> >
> > Thank you all.
> >
> > v2->v3:
> > ÂÂ Fix build error when KASLR is disabled.
> > v1->v2:
> > ÂÂ Add __kaslr_offset for the secondary cpu boot up.
> >
> > Jason Yan (6):
> > ÂÂ powerpc/fsl_booke/kaslr: refactor kaslr_legal_offset() and
> > ÂÂÂÂ kaslr_early_init()
> > ÂÂ powerpc/fsl_booke/64: introduce reloc_kernel_entry() helper
> > ÂÂ powerpc/fsl_booke/64: implement KASLR for fsl_booke64
> > ÂÂ powerpc/fsl_booke/64: do not clear the BSS for the second pass
> > ÂÂ powerpc/fsl_booke/64: clear the original kernel if randomized
> > ÂÂ powerpc/fsl_booke/kaslr: rename kaslr-booke32.rst to kaslr-booke.rst
> > ÂÂÂÂ and add 64bit part
> >
> > Â .../{kaslr-booke32.rst => kaslr-booke.rst}ÂÂÂ | 35 +++++++--
> > Â arch/powerpc/KconfigÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ |Â 2 +-
> > Â arch/powerpc/kernel/exceptions-64e.SÂÂÂÂÂÂÂÂÂ | 23 ++++++
> > Â arch/powerpc/kernel/head_64.SÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ | 14 ++++
> > Â arch/powerpc/kernel/setup_64.cÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ |Â 4 +-
> > Â arch/powerpc/mm/mmu_decl.hÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ | 19 ++---
> > Â arch/powerpc/mm/nohash/kaslr_booke.cÂÂÂÂÂÂÂÂÂ | 71 +++++++++++++------
> > Â 7 files changed, 132 insertions(+), 36 deletions(-)
> > Â rename Documentation/powerpc/{kaslr-booke32.rst => kaslr-booke.rst} 
> > (59%)
>
>
> .