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/arc/Makefile | 108 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 108 insertions(+) create mode 100644 arch/arc/Makefile (limited to 'arch/arc/Makefile') diff --git a/arch/arc/Makefile b/arch/arc/Makefile new file mode 100644 index 000000000..868805ffc --- /dev/null +++ b/arch/arc/Makefile @@ -0,0 +1,108 @@ +# SPDX-License-Identifier: GPL-2.0-only +# +# Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com) +# + +KBUILD_DEFCONFIG := haps_hs_smp_defconfig + +ifeq ($(CROSS_COMPILE),) +CROSS_COMPILE := $(call cc-cross-prefix, arc-linux- arceb-linux- arc-linux-gnu-) +endif + +cflags-y += -fno-common -pipe -fno-builtin -mmedium-calls -mswape -D__linux__ + +tune-mcpu-def-$(CONFIG_ISA_ARCOMPACT) := -mcpu=arc700 +tune-mcpu-def-$(CONFIG_ISA_ARCV2) := -mcpu=hs38 + +ifeq ($(CONFIG_ARC_TUNE_MCPU),) +cflags-y += $(tune-mcpu-def-y) +else +tune-mcpu := $(CONFIG_ARC_TUNE_MCPU) +ifneq ($(call cc-option,$(tune-mcpu)),) +cflags-y += $(tune-mcpu) +else +# The flag provided by 'CONFIG_ARC_TUNE_MCPU' option isn't known by this compiler +# (probably the compiler is too old). Use ISA default mcpu flag instead as a safe option. +$(warning ** WARNING ** CONFIG_ARC_TUNE_MCPU flag '$(tune-mcpu)' is unknown, fallback to '$(tune-mcpu-def-y)') +cflags-y += $(tune-mcpu-def-y) +endif +endif + +ifdef CONFIG_ARC_CURR_IN_REG +# For a global register definition, make sure it gets passed to every file +# We had a customer reported bug where some code built in kernel was NOT using +# any kernel headers, and missing the global register +# Can't do unconditionally because of recursive include issues +# due to +LINUXINCLUDE += -include $(srctree)/arch/arc/include/asm/current.h +cflags-y += -ffixed-gp +endif + +cflags-y += -fsection-anchors + +cflags-$(CONFIG_ARC_HAS_LLSC) += -mlock + +ifdef CONFIG_ISA_ARCV2 + +ifdef CONFIG_ARC_USE_UNALIGNED_MEM_ACCESS +cflags-y += -munaligned-access +else +cflags-y += -mno-unaligned-access +endif + +ifndef CONFIG_ARC_HAS_LL64 +cflags-y += -mno-ll64 +endif + +ifndef CONFIG_ARC_HAS_DIV_REM +cflags-y += -mno-div-rem +endif + +endif + +cfi := $(call as-instr,.cfi_startproc\n.cfi_endproc,-DARC_DW2_UNWIND_AS_CFI) +cflags-$(CONFIG_ARC_DW2_UNWIND) += -fasynchronous-unwind-tables $(cfi) + +# small data is default for elf32 tool-chain. If not usable, disable it +# This also allows repurposing GP as scratch reg to gcc reg allocator +disable_small_data := y +cflags-$(disable_small_data) += -mno-sdata + +cflags-$(CONFIG_CPU_BIG_ENDIAN) += -mbig-endian +ldflags-$(CONFIG_CPU_BIG_ENDIAN) += -EB + +LIBGCC = $(shell $(CC) $(cflags-y) --print-libgcc-file-name) + +# Modules with short calls might break for calls into builtin-kernel +KBUILD_CFLAGS_MODULE += -mlong-calls -mno-millicode + +# Finally dump eveything into kernel build system +KBUILD_CFLAGS += $(cflags-y) +KBUILD_AFLAGS += $(KBUILD_CFLAGS) +KBUILD_LDFLAGS += $(ldflags-y) + +core-y += arch/arc/plat-sim/ +core-$(CONFIG_ARC_PLAT_TB10X) += arch/arc/plat-tb10x/ +core-$(CONFIG_ARC_PLAT_AXS10X) += arch/arc/plat-axs10x/ +core-$(CONFIG_ARC_SOC_HSDK) += arch/arc/plat-hsdk/ + +libs-y += arch/arc/lib/ $(LIBGCC) + +boot := arch/arc/boot + +boot_targets := uImage.bin uImage.gz uImage.lzma + +PHONY += $(boot_targets) +$(boot_targets): vmlinux + $(Q)$(MAKE) $(build)=$(boot) $(boot)/$@ + +uimage-default-y := uImage.bin +uimage-default-$(CONFIG_KERNEL_GZIP) := uImage.gz +uimage-default-$(CONFIG_KERNEL_LZMA) := uImage.lzma + +PHONY += uImage +uImage: $(uimage-default-y) + @ln -sf $< $(boot)/uImage + @$(kecho) ' Image $(boot)/uImage is ready' + +CLEAN_FILES += $(boot)/uImage -- cgit v1.3.1