On Thu, Apr 06, 2017 at 04:52:11PM +0200, Juergen Gross wrote: > On 06/04/17 16:01, Kirill A. Shutemov wrote: > > Most of things are in place and we can enable support of 5-level paging. > > > > Enabling XEN with 5-level paging requires more work. The patch makes XEN > > dependent on !X86_5LEVEL. > > > > Signed-off-by: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx> > > --- > > arch/x86/Kconfig | 5 +++++ > > arch/x86/xen/Kconfig | 1 + > > 2 files changed, 6 insertions(+) > > > > diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig > > index 4e153e93273f..7a76dcac357e 100644 > > --- a/arch/x86/Kconfig > > +++ b/arch/x86/Kconfig > > @@ -318,6 +318,7 @@ config FIX_EARLYCON_MEM > > > > config PGTABLE_LEVELS > > int > > + default 5 if X86_5LEVEL > > default 4 if X86_64 > > default 3 if X86_PAE > > default 2 > > @@ -1390,6 +1391,10 @@ config X86_PAE > > has the cost of more pagetable lookup overhead, and also > > consumes more pagetable space per process. > > > > +config X86_5LEVEL > > + bool "Enable 5-level page tables support" > > + depends on X86_64 > > + > > config ARCH_PHYS_ADDR_T_64BIT > > def_bool y > > depends on X86_64 || X86_PAE > > diff --git a/arch/x86/xen/Kconfig b/arch/x86/xen/Kconfig > > index 76b6dbd627df..b90d481ce5a1 100644 > > --- a/arch/x86/xen/Kconfig > > +++ b/arch/x86/xen/Kconfig > > @@ -5,6 +5,7 @@ > > config XEN > > bool "Xen guest support" > > depends on PARAVIRT > > + depends on !X86_5LEVEL > > select PARAVIRT_CLOCK > > select XEN_HAVE_PVMMU > > select XEN_HAVE_VPMU > > > > Just a heads up: this last change will conflict with the Xen tree. It should be trivial to fix, right? It's one-liner after all. > Can't we just ignore the additional level in Xen pv mode and run with > 4 levels instead? We don't have yet boot-time switching between paging modes yet. It will come later. So the answer is no. -- Kirill A. Shutemov -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>
