From 93de2a6a4b91b72607136dd656edf03fb399d27f Mon Sep 17 00:00:00 2001 From: Sean Christopherson Date: Wed, 23 Sep 2026 09:37:21 -0700 Subject: KVM: SEV: Do cache maintenance on the source VM during intra-host migration Manually perform cache maintenance on the source VM during intra-host migration to ensure no stale data is left in CPU caches after the VM is destroyed. Because the source VM is "converted" to a non-SEV VM, KVM's memory reclaim flows won't trigger cache maintenance, e.g. when all guest memory is reclaimed in response to detaching from the mmu_notifier. Note, relying on the destination VM to do cache maintenance isn't an option as KVM doesn't require identical guest memory configurations, i.e. the source VM may have access to memory that the destination VM does not. Enforcing equivalent memory configurations is infeasible, as it would require a *deep* comparison of memslots, e.g. to verify that not only are the memslot identical, but what the memslots point at is also identical. Fixes: b56639318bb2 ("KVM: SEV: Add support for SEV intra host migration") Cc: stable@vger.kernel.org Reported-by: Stefan Teodorescu Signed-off-by: Sean Christopherson Message-ID: <20260923163721.1584779-3-seanjc@google.com> Signed-off-by: Paolo Bonzini --- scripts/kconfig/Makefile | 236 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 236 insertions(+) create mode 100644 scripts/kconfig/Makefile (limited to 'scripts/kconfig/Makefile') diff --git a/scripts/kconfig/Makefile b/scripts/kconfig/Makefile new file mode 100644 index 000000000..5baf1c44f --- /dev/null +++ b/scripts/kconfig/Makefile @@ -0,0 +1,236 @@ +# SPDX-License-Identifier: GPL-2.0 +# =========================================================================== +# Kernel configuration targets +# These targets are used from top-level makefile + +ifdef KBUILD_KCONFIG +Kconfig := $(KBUILD_KCONFIG) +else +Kconfig := Kconfig +endif + +ifndef KBUILD_DEFCONFIG +KBUILD_DEFCONFIG := defconfig +endif + +ifeq ($(quiet),silent_) +silent := -s +endif + +export KCONFIG_DEFCONFIG_LIST := +ifndef cross_compiling +kernel-release := $(shell uname -r) +KCONFIG_DEFCONFIG_LIST += \ + /lib/modules/$(kernel-release)/.config \ + /etc/kernel-config \ + /boot/config-$(kernel-release) +endif +KCONFIG_DEFCONFIG_LIST += arch/$(SRCARCH)/configs/$(KBUILD_DEFCONFIG) + +ifneq ($(findstring c, $(KBUILD_EXTRA_WARN)),) +export KCONFIG_WARN_UNKNOWN_SYMBOLS=1 +endif + +ifneq ($(findstring e, $(KBUILD_EXTRA_WARN)),) +export KCONFIG_WERROR=1 +endif + +# We need this, in case the user has it in its environment +unexport CONFIG_ + +config-prog := conf +menuconfig-prog := mconf +nconfig-prog := nconf +gconfig-prog := gconf +xconfig-prog := qconf + +define config_rule +PHONY += $(1) +$(1): $(obj)/$($(1)-prog) + $(Q)$$< $(silent) $(Kconfig) + +PHONY += build_$(1) +build_$(1): $(obj)/$($(1)-prog) +endef + +$(foreach c, config menuconfig nconfig gconfig xconfig, $(eval $(call config_rule,$(c)))) + +PHONY += localmodconfig localyesconfig +localyesconfig localmodconfig: $(obj)/conf + $(Q)$(PERL) $(src)/streamline_config.pl --$@ $(srctree) $(Kconfig) > .tmp.config + $(Q)if [ -f .config ]; then \ + cmp -s .tmp.config .config || \ + (mv -f .config .config.old.1; \ + mv -f .tmp.config .config; \ + $< $(silent) --oldconfig $(Kconfig); \ + mv -f .config.old.1 .config.old) \ + else \ + mv -f .tmp.config .config; \ + $< $(silent) --oldconfig $(Kconfig); \ + fi + $(Q)rm -f .tmp.config + +# These targets map 1:1 to the commandline options of 'conf' +# +# Note: +# syncconfig has become an internal implementation detail and is now +# deprecated for external use +simple-targets := oldconfig allnoconfig allyesconfig allmodconfig \ + alldefconfig randconfig listnewconfig olddefconfig syncconfig \ + helpnewconfig yes2modconfig mod2yesconfig mod2noconfig + +PHONY += $(simple-targets) + +$(simple-targets): $(obj)/conf + $(Q)$< $(silent) --$@ $(Kconfig) + +PHONY += savedefconfig defconfig + +savedefconfig: $(obj)/conf + $(Q)$< $(silent) --$@=defconfig $(Kconfig) + +defconfig: $(obj)/conf +ifneq ($(wildcard $(srctree)/arch/$(SRCARCH)/configs/$(KBUILD_DEFCONFIG)),) + @$(kecho) "*** Default configuration is based on '$(KBUILD_DEFCONFIG)'" + $(Q)$< $(silent) --defconfig=arch/$(SRCARCH)/configs/$(KBUILD_DEFCONFIG) $(Kconfig) +else + @$(kecho) "*** Default configuration is based on target '$(KBUILD_DEFCONFIG)'" + $(Q)$(MAKE) -f $(srctree)/Makefile $(KBUILD_DEFCONFIG) +endif + +%_defconfig: $(obj)/conf + $(Q)$< $(silent) --defconfig=arch/$(SRCARCH)/configs/$@ $(Kconfig) + +configfiles = $(wildcard $(srctree)/kernel/configs/$(1) $(srctree)/arch/$(SRCARCH)/configs/$(1)) +all-config-fragments = $(call configfiles,*.config) +config-fragments = $(call configfiles,$@) + +cmd_merge_fragments = $(srctree)/scripts/kconfig/merge_config.sh -m $(KCONFIG_CONFIG) $(config-fragments) + +%.config: $(obj)/conf + $(if $(config-fragments),, $(error $@ fragment does not exists on this architecture)) + $(call cmd,merge_fragments) + $(Q)$(MAKE) -f $(srctree)/Makefile olddefconfig + +PHONY += tinyconfig +tinyconfig: + $(Q)KCONFIG_ALLCONFIG=kernel/configs/tiny-base.config $(MAKE) -f $(srctree)/Makefile allnoconfig + $(Q)$(MAKE) -f $(srctree)/Makefile tiny.config + +# CHECK: -o cache_dir= working? +PHONY += testconfig +testconfig: $(obj)/conf + $(Q)$(PYTHON3) -B -m pytest $(src)/tests \ + -o cache_dir=$(abspath $(obj)/tests/.cache) \ + $(if $(findstring 1,$(KBUILD_VERBOSE)),--capture=no) +clean-files += tests/.cache + +# Help text used by make help +help: + @echo 'Configuration targets:' + @echo ' config - Update current config utilising a line-oriented program' + @echo ' nconfig - Update current config utilising a ncurses menu based program' + @echo ' menuconfig - Update current config utilising a menu based program' + @echo ' xconfig - Update current config utilising a Qt based front-end' + @echo ' gconfig - Update current config utilising a GTK+ based front-end' + @echo ' oldconfig - Update current config utilising a provided .config as base' + @echo ' localmodconfig - Update current config disabling modules not loaded' + @echo ' except those preserved by LMC_KEEP environment variable' + @echo ' localyesconfig - Update current config converting local mods to core' + @echo ' except those preserved by LMC_KEEP environment variable' + @echo ' defconfig - New config with default from ARCH supplied defconfig' + @echo ' savedefconfig - Save current config as ./defconfig (minimal config)' + @echo ' allnoconfig - New config where all options are answered with no' + @echo ' allyesconfig - New config where all options are accepted with yes' + @echo ' allmodconfig - New config selecting modules when possible' + @echo ' alldefconfig - New config with all symbols set to default' + @echo ' randconfig - New config with random answer to all options' + @echo ' yes2modconfig - Change answers from yes to mod if possible' + @echo ' mod2yesconfig - Change answers from mod to yes if possible' + @echo ' mod2noconfig - Change answers from mod to no if possible' + @echo ' listnewconfig - List new options' + @echo ' helpnewconfig - List new options and help text' + @echo ' olddefconfig - Same as oldconfig but sets new symbols to their' + @echo ' default value without prompting' + @echo ' tinyconfig - Configure the tiniest possible kernel' + @echo ' testconfig - Run Kconfig unit tests (requires python3 and pytest)' + @echo '' + @echo 'Configuration topic targets:' + @$(foreach f, $(all-config-fragments), \ + if help=$$(grep -m1 '^# Help: ' $(f)); then \ + printf ' %-25s - %s\n' '$(notdir $(f))' "$${help#*: }"; \ + fi;) + +# =========================================================================== +# object files used by all kconfig flavours +common-objs := confdata.o expr.o lexer.lex.o menu.o parser.tab.o \ + preprocess.o symbol.o util.o + +$(obj)/lexer.lex.o: $(obj)/parser.tab.h +HOSTCFLAGS_lexer.lex.o := -I $(src) +HOSTCFLAGS_parser.tab.o := -I $(src) + +# conf: Used for defconfig, oldconfig and related targets +hostprogs += conf +conf-objs := conf.o $(common-objs) + +# nconf: Used for the nconfig target based on ncurses +hostprogs += nconf +nconf-objs := nconf.o nconf.gui.o mnconf-common.o $(common-objs) + +HOSTLDLIBS_nconf = $(call read-file, $(obj)/nconf-libs) +HOSTCFLAGS_nconf.o = $(call read-file, $(obj)/nconf-cflags) +HOSTCFLAGS_nconf.gui.o = $(call read-file, $(obj)/nconf-cflags) + +$(obj)/nconf: | $(obj)/nconf-libs +$(obj)/nconf.o $(obj)/nconf.gui.o: | $(obj)/nconf-cflags + +# mconf: Used for the menuconfig target based on lxdialog +hostprogs += mconf +lxdialog := $(addprefix lxdialog/, \ + checklist.o inputbox.o menubox.o textbox.o util.o yesno.o) +mconf-objs := mconf.o $(lxdialog) mnconf-common.o $(common-objs) + +HOSTLDLIBS_mconf = $(call read-file, $(obj)/mconf-libs) +$(foreach f, mconf.o $(lxdialog), \ + $(eval HOSTCFLAGS_$f = $$(call read-file, $(obj)/mconf-cflags))) + +$(obj)/mconf: | $(obj)/mconf-libs +$(addprefix $(obj)/, mconf.o $(lxdialog)): | $(obj)/mconf-cflags + +# qconf: Used for the xconfig target based on Qt +hostprogs += qconf +qconf-cxxobjs := qconf.o qconf-moc.o +qconf-objs := $(common-objs) + +HOSTLDLIBS_qconf = $(call read-file, $(obj)/qconf-libs) +HOSTCXXFLAGS_qconf.o = -std=c++11 -fPIC $(call read-file, $(obj)/qconf-cflags) +HOSTCXXFLAGS_qconf-moc.o = -std=c++11 -fPIC $(call read-file, $(obj)/qconf-cflags) +$(obj)/qconf: | $(obj)/qconf-libs +$(obj)/qconf.o $(obj)/qconf-moc.o: | $(obj)/qconf-cflags + +quiet_cmd_moc = MOC $@ + cmd_moc = $(call read-file, $(obj)/qconf-bin)/moc $< -o $@ + +$(obj)/qconf-moc.cc: $(src)/qconf.h FORCE | $(obj)/qconf-bin + $(call if_changed,moc) + +targets += qconf-moc.cc + +# gconf: Used for the gconfig target based on GTK+ +hostprogs += gconf +gconf-objs := gconf.o $(common-objs) + +HOSTLDLIBS_gconf = $(call read-file, $(obj)/gconf-libs) +HOSTCFLAGS_gconf.o = $(call read-file, $(obj)/gconf-cflags) + +$(obj)/gconf: | $(obj)/gconf-libs +$(obj)/gconf.o: | $(obj)/gconf-cflags + +# check if necessary packages are available, and configure build flags +cmd_conf_cfg = $< $(addprefix $(obj)/$*conf-, cflags libs bin); touch $(obj)/$*conf-bin + +$(obj)/%conf-cflags $(obj)/%conf-libs $(obj)/%conf-bin: $(src)/%conf-cfg.sh + $(call cmd,conf_cfg) + +clean-files += *conf-cflags *conf-libs *conf-bin -- cgit v1.3.1