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# SPDX-License-Identifier: GPL-2.0
#
# Makefile for Kernel-based Virtual Machine module, HYP/nVHE part
#
asflags-y := -D__KVM_NVHE_HYPERVISOR__ -D__DISABLE_EXPORTS
# Tracepoint and MMIO logging symbols should not be visible at nVHE KVM as
# there is no way to execute them and any such MMIO access from nVHE KVM
# will explode instantly (Words of Marc Zyngier). So introduce a generic flag
# __DISABLE_TRACE_MMIO__ to disable MMIO tracing for nVHE KVM.
ccflags-y := -D__KVM_NVHE_HYPERVISOR__ -D__DISABLE_EXPORTS -D__DISABLE_TRACE_MMIO__
ccflags-y += -fno-stack-protector \
-DDISABLE_BRANCH_PROFILING \
$(DISABLE_STACKLEAK_PLUGIN)
hostprogs := gen-hyprel
HOST_EXTRACFLAGS += -I$(objtree)/include
lib-objs := clear_page.o copy_page.o memcpy.o memset.o
lib-objs := $(addprefix ../../../lib/, $(lib-objs))
hyp-obj-y := timer-sr.o sysreg-sr.o debug-sr.o switch.o tlb.o hyp-init.o host.o \
hyp-main.o hyp-smp.o psci-relay.o early_alloc.o page_alloc.o \
cache.o setup.o mm.o mem_protect.o sys_regs.o pkvm.o stacktrace.o ffa.o
hyp-obj-y += ../vgic-v3-sr.o ../aarch32.o ../vgic-v2-cpuif-proxy.o ../entry.o \
../fpsimd.o ../hyp-entry.o ../exception.o ../pgtable.o
hyp-obj-$(CONFIG_DEBUG_LIST) += list_debug.o
hyp-obj-y += $(lib-objs)
##
## Build rules for compiling nVHE hyp code
## Output of this folder is `kvm_nvhe.o`, a partially linked object
## file containing all nVHE hyp code and data.
##
hyp-obj := $(patsubst %.o,%.nvhe.o,$(hyp-obj-y))
obj-y := kvm_nvhe.o
targets += $(hyp-obj) kvm_nvhe.tmp.o kvm_nvhe.rel.o hyp.lds hyp-reloc.S hyp-reloc.o
# 1) Compile all source files to `.nvhe.o` object files. The file extension
# avoids file name clashes for files shared with VHE.
$(obj)/%.nvhe.o: $(src)/%.c FORCE
$(call if_changed_rule,cc_o_c)
$(obj)/%.nvhe.o: $(src)/%.S FORCE
$(call if_changed_rule,as_o_S)
# 2) Compile linker script.
$(obj)/hyp.lds: $(src)/hyp.lds.S FORCE
$(call if_changed_dep,cpp_lds_S)
# 3) Partially link all '.nvhe.o' files and apply the linker script.
# Prefixes names of ELF sections with '.hyp', eg. '.hyp.text'.
# Note: The following rule assumes that the 'ld' rule puts LDFLAGS before
# the list of dependencies to form '-T $(obj)/hyp.lds'. This is to
# keep the dependency on the target while avoiding an error from
# GNU ld if the linker script is passed to it twice.
LDFLAGS_kvm_nvhe.tmp.o := -r -T
$(obj)/kvm_nvhe.tmp.o: $(obj)/hyp.lds $(addprefix $(obj)/,$(hyp-obj)) FORCE
$(call if_changed,ld)
# 4) Generate list of hyp code/data positions that need to be relocated at
# runtime. Because the hypervisor is part of the kernel binary, relocations
# produce a kernel VA. We enumerate relocations targeting hyp at build time
# and convert the kernel VAs at those positions to hyp VAs.
$(obj)/hyp-reloc.S: $(obj)/kvm_nvhe.tmp.o $(obj)/gen-hyprel FORCE
$(call if_changed,hyprel)
# 5) Compile hyp-reloc.S and link it into the existing partially linked object.
# The object file now contains a section with pointers to hyp positions that
# will contain kernel VAs at runtime. These pointers have relocations on them
# so that they get updated as the hyp object is linked into `vmlinux`.
LDFLAGS_kvm_nvhe.rel.o := -r
$(obj)/kvm_nvhe.rel.o: $(obj)/kvm_nvhe.tmp.o $(obj)/hyp-reloc.o FORCE
$(call if_changed,ld)
# 6) Produce the final 'kvm_nvhe.o', ready to be linked into 'vmlinux'.
# Prefixes names of ELF symbols with '__kvm_nvhe_'.
$(obj)/kvm_nvhe.o: $(obj)/kvm_nvhe.rel.o FORCE
$(call if_changed,hypcopy)
# The HYPREL command calls `gen-hyprel` to generate an assembly file with
# a list of relocations targeting hyp code/data.
quiet_cmd_hyprel = HYPREL $@
cmd_hyprel = $(obj)/gen-hyprel $< > $@
# The HYPCOPY command uses `objcopy` to prefix all ELF symbol names
# to avoid clashes with VHE code/data.
quiet_cmd_hypcopy = HYPCOPY $@
cmd_hypcopy = $(OBJCOPY) --prefix-symbols=__kvm_nvhe_ $< $@
# Remove ftrace, Shadow Call Stack, and CFI CFLAGS.
# This is equivalent to the 'notrace', '__noscs', and '__nocfi' annotations.
KBUILD_CFLAGS := $(filter-out $(CC_FLAGS_FTRACE) $(CC_FLAGS_SCS) $(CC_FLAGS_CFI), $(KBUILD_CFLAGS))
# Starting from 13.0.0 llvm emits SHT_REL section '.llvm.call-graph-profile'
# when profile optimization is applied. gen-hyprel does not support SHT_REL and
# causes a build failure. Remove profile optimization flags.
KBUILD_CFLAGS := $(filter-out -fprofile-sample-use=% -fprofile-use=%, $(KBUILD_CFLAGS))
KBUILD_CFLAGS += -fno-asynchronous-unwind-tables -fno-unwind-tables
# KVM nVHE code is run at a different exception code with a different map, so
# compiler instrumentation that inserts callbacks or checks into the code may
# cause crashes. Just disable it.
GCOV_PROFILE := n
KASAN_SANITIZE := n
KCSAN_SANITIZE := n
UBSAN_SANITIZE := n
KCOV_INSTRUMENT := n
# Skip objtool checking for this directory because nVHE code is compiled with
# non-standard build rules.
OBJECT_FILES_NON_STANDARD := y
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