On Mon, 2016-01-18 at 18:40 +0000, Andrew Cooper wrote: > Signed-off-by: Andrew Cooper <andrew.coop...@citrix.com>
Does this have any impact on migration of either PV or HVM guests? What about nested virt? Are things which are defined in xen/arch/*/Rules.mk in this way overrideable from the old top-level .config or does one need to dive deeper to modify them? If it's not configurable from top-level .config today then I think it either needs a "depends EXPERT" or for the changelog to make a convincing argument why this should be made user selectable. Lastly, Tim is maintainer of the shadow code and should have been CC-d, also George as maintainer of the mm stuff might have an interest. Both CC-s added. > --- > CC: Jan Beulich <jbeul...@suse.com> > CC: Doug Goldstein <car...@cardoe.com> > --- > xen/arch/x86/Kconfig | 14 ++++++++++++++ > xen/arch/x86/Rules.mk | 4 ---- > xen/arch/x86/mm/shadow/Makefile | 2 +- > 3 files changed, 15 insertions(+), 5 deletions(-) > > diff --git a/xen/arch/x86/Kconfig b/xen/arch/x86/Kconfig > index 4781b34..9869630 100644 > --- a/xen/arch/x86/Kconfig > +++ b/xen/arch/x86/Kconfig > @@ -27,6 +27,20 @@ menu "Architecture Features" > > source "arch/Kconfig" > > +config SHADOW_PAGING > + bool "Shadow Paging" > + default y > + ---help--- > + Shadow paging is a software alternative to hardware paging > support > + (Intel EPT, AMD NPT) for use with HVM guests. > + > + It is required to run HVM guests for first-generation hardware > + virtualisation (Intel VT-x, AMD SVM) which did not include > hardware > + paging support. Under a small number of specific workloads, > shadow > + paging may also be deliberately used as a performance > improvement. > + > + If unsure, say Y. > + > config BIGMEM > bool "big memory support" > default n > diff --git a/xen/arch/x86/Rules.mk b/xen/arch/x86/Rules.mk > index a108d24..a1cdae0 100644 > --- a/xen/arch/x86/Rules.mk > +++ b/xen/arch/x86/Rules.mk > @@ -22,13 +22,9 @@ $(call as-insn-check,CFLAGS,CC,".equ \"x\"$$(comma)1", > \ > -U__OBJECT_LABEL__ -DHAVE_GAS_QUOTED_SYM \ > '-D__OBJECT_LABEL__=$(subst > $(BASEDIR)/,,$(CURDIR))/$$@') > > -shadow-paging ?= y > - > CFLAGS += -mno-red-zone -mno-sse -fpic > CFLAGS += -fno-asynchronous-unwind-tables > # -fvisibility=hidden reduces -fpic cost, if it's available > ifneq ($(call cc-option,$(CC),-fvisibility=hidden,n),n) > CFLAGS += -DGCC_HAS_VISIBILITY_ATTRIBUTE > endif > - > -CFLAGS-$(shadow-paging) += -DCONFIG_SHADOW_PAGING > diff --git a/xen/arch/x86/mm/shadow/Makefile > b/xen/arch/x86/mm/shadow/Makefile > index a07bc0c..df194ad 100644 > --- a/xen/arch/x86/mm/shadow/Makefile > +++ b/xen/arch/x86/mm/shadow/Makefile > @@ -1,4 +1,4 @@ > -ifeq ($(shadow-paging),y) > +ifdef CONFIG_SHADOW_PAGING > obj-y += common.o guest_2.o guest_3.o guest_4.o > else > obj-y += none.o _______________________________________________ Xen-devel mailing list Xen-devel@lists.xen.org http://lists.xen.org/xen-devel