On Tue, Dec 12, 2017 at 09:44:09AM +0100, Geert Uytterhoeven wrote: > Hi Will, > > On Thu, Nov 30, 2017 at 5:39 PM, Will Deacon <[email protected]> wrote: > > Add a Kconfig entry to control use of the entry trampoline, which allows > > us to unmap the kernel whilst running in userspace and improve the > > robustness of KASLR. > > > > Signed-off-by: Will Deacon <[email protected]> > > This is now commit 084eb77cd3a81134 in arm64/for-next/core. > > > --- > > arch/arm64/Kconfig | 13 +++++++++++++ > > 1 file changed, 13 insertions(+) > > > > diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig > > index fdcc7b9bb15d..3af1657fcac3 100644 > > --- a/arch/arm64/Kconfig > > +++ b/arch/arm64/Kconfig > > @@ -833,6 +833,19 @@ config FORCE_MAX_ZONEORDER > > However for 4K, we choose a higher default value, 11 as opposed > > to 10, giving us > > 4M allocations matching the default size used by generic code. > > > > +config UNMAP_KERNEL_AT_EL0 > > + bool "Unmap kernel when running in userspace (aka \"KAISER\")" > > But I believe this is no longer called KAISER?
That's right, but KAISER is the original name in the paper and so I figured it was worth mentioning just here to help people identify what this feature is. The command line option is "kpti" to align with x86. Will
