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 --- arch/alpha/Makefile | 66 +++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 66 insertions(+) create mode 100644 arch/alpha/Makefile (limited to 'arch/alpha/Makefile') diff --git a/arch/alpha/Makefile b/arch/alpha/Makefile new file mode 100644 index 000000000..7074602dc --- /dev/null +++ b/arch/alpha/Makefile @@ -0,0 +1,66 @@ +# +# alpha/Makefile +# +# This file is subject to the terms and conditions of the GNU General Public +# License. See the file "COPYING" in the main directory of this archive +# for more details. +# +# Copyright (C) 1994 by Linus Torvalds +# + +NM := $(NM) -B + +LDFLAGS_vmlinux := -static -N #-relax +CHECKFLAGS += -D__alpha__ +cflags-y := -pipe -mno-fp-regs -ffixed-8 +cflags-y += $(call cc-option, -fno-jump-tables) + +cpuflags-$(CONFIG_ALPHA_EV56) := -mcpu=ev56 +cpuflags-$(CONFIG_ALPHA_POLARIS) := -mcpu=pca56 +cpuflags-$(CONFIG_ALPHA_SX164) := -mcpu=pca56 +cpuflags-$(CONFIG_ALPHA_EV6) := -mcpu=ev6 +cpuflags-$(CONFIG_ALPHA_EV67) := -mcpu=ev67 +# If GENERIC, make sure to turn off any instruction set extensions that +# the host compiler might have on by default. +cpuflags-$(CONFIG_ALPHA_GENERIC) := -mcpu=ev56 -mtune=ev6 + +cflags-y += $(cpuflags-y) + + +KBUILD_CFLAGS += $(cflags-y) + +# For TSUNAMI, we must have the assembler not emulate our instructions. +# The same is true for IRONGATE, POLARIS, PYXIS. +# BWX is most important, but we don't really want any emulation ever. +# Only gas emulates instructions the target does not implement, and only gas +# understands -mev6. LLVM's integrated assembler never emulates. +ifdef CONFIG_AS_IS_GNU +KBUILD_CFLAGS += -Wa,-mev6 +endif + +libs-y += arch/alpha/lib/ + +# export what is needed by arch/alpha/boot/Makefile +LIBS_Y := $(patsubst %/, %/lib.a, $(libs-y)) +export LIBS_Y + +boot := arch/alpha/boot + +#Default target when executing make with no arguments +all boot: $(boot)/vmlinux.gz + +$(boot)/vmlinux.gz: vmlinux + $(Q)$(MAKE) $(build)=$(boot) $@ + +bootimage bootpfile bootpzfile: vmlinux + $(Q)$(MAKE) $(build)=$(boot) $(boot)/$@ + +archheaders: + $(Q)$(MAKE) $(build)=arch/alpha/kernel/syscalls all + +define archhelp + echo '* boot - Compressed kernel image (arch/alpha/boot/vmlinux.gz)' + echo ' bootimage - SRM bootable image (arch/alpha/boot/bootimage)' + echo ' bootpfile - BOOTP bootable image (arch/alpha/boot/bootpfile)' + echo ' bootpzfile - compressed kernel BOOTP image (arch/alpha/boot/bootpzfile)' +endef -- cgit v1.3.1