Makefile

  1# SPDX-License-Identifier: GPL-2.0
  2#
  3# Makefile for Kernel-based Virtual Machine module, HYP/nVHE part
  4#
  5
  6asflags-y := -D__KVM_NVHE_HYPERVISOR__ -D__DISABLE_EXPORTS
  7
  8# Tracepoint and MMIO logging symbols should not be visible at nVHE KVM as
  9# there is no way to execute them and any such MMIO access from nVHE KVM
 10# will explode instantly (Words of Marc Zyngier). So introduce a generic flag
 11# __DISABLE_TRACE_MMIO__ to disable MMIO tracing for nVHE KVM.
 12ccflags-y := -D__KVM_NVHE_HYPERVISOR__ -D__DISABLE_EXPORTS -D__DISABLE_TRACE_MMIO__
 13ccflags-y += -fno-stack-protector	\
 14	     -DDISABLE_BRANCH_PROFILING	\
 15	     $(DISABLE_KSTACK_ERASE)
 16
 17hostprogs := gen-hyprel
 18HOST_EXTRACFLAGS += -I$(objtree)/include
 19
 20lib-objs := clear_page.o copy_page.o memcpy.o memset.o
 21lib-objs := $(addprefix ../../../lib/, $(lib-objs))
 22
 23CFLAGS_switch.nvhe.o += -Wno-override-init
 24
 25hyp-obj-y := timer-sr.o sysreg-sr.o debug-sr.o switch.o tlb.o hyp-init.o host.o \
 26	 hyp-main.o hyp-smp.o psci-relay.o early_alloc.o page_alloc.o \
 27	 cache.o setup.o mm.o mem_protect.o sys_regs.o pkvm.o stacktrace.o ffa.o
 28hyp-obj-y += ../vgic-v3-sr.o ../aarch32.o ../vgic-v2-cpuif-proxy.o ../entry.o \
 29	 ../fpsimd.o ../hyp-entry.o ../exception.o ../pgtable.o
 30hyp-obj-y += ../../../kernel/smccc-call.o
 31hyp-obj-$(CONFIG_LIST_HARDENED) += list_debug.o
 32hyp-obj-y += $(lib-objs)
 33
 34##
 35## Build rules for compiling nVHE hyp code
 36## Output of this folder is `kvm_nvhe.o`, a partially linked object
 37## file containing all nVHE hyp code and data.
 38##
 39
 40hyp-obj := $(patsubst %.o,%.nvhe.o,$(hyp-obj-y))
 41obj-y := kvm_nvhe.o
 42targets += $(hyp-obj) kvm_nvhe.tmp.o kvm_nvhe.rel.o hyp.lds hyp-reloc.S hyp-reloc.o
 43
 44# 1) Compile all source files to `.nvhe.o` object files. The file extension
 45#    avoids file name clashes for files shared with VHE.
 46$(obj)/%.nvhe.o: $(src)/%.c FORCE
 47	$(call if_changed_rule,cc_o_c)
 48$(obj)/%.nvhe.o: $(src)/%.S FORCE
 49	$(call if_changed_rule,as_o_S)
 50
 51# 2) Compile linker script.
 52$(obj)/hyp.lds: $(src)/hyp.lds.S FORCE
 53	$(call if_changed_dep,cpp_lds_S)
 54
 55# 3) Partially link all '.nvhe.o' files and apply the linker script.
 56#    Prefixes names of ELF sections with '.hyp', eg. '.hyp.text'.
 57#    Note: The following rule assumes that the 'ld' rule puts LDFLAGS before
 58#          the list of dependencies to form '-T $(obj)/hyp.lds'. This is to
 59#          keep the dependency on the target while avoiding an error from
 60#          GNU ld if the linker script is passed to it twice.
 61LDFLAGS_kvm_nvhe.tmp.o := -r -T
 62$(obj)/kvm_nvhe.tmp.o: $(obj)/hyp.lds $(addprefix $(obj)/,$(hyp-obj)) FORCE
 63	$(call if_changed,ld)
 64
 65# 4) Generate list of hyp code/data positions that need to be relocated at
 66#    runtime. Because the hypervisor is part of the kernel binary, relocations
 67#    produce a kernel VA. We enumerate relocations targeting hyp at build time
 68#    and convert the kernel VAs at those positions to hyp VAs.
 69$(obj)/hyp-reloc.S: $(obj)/kvm_nvhe.tmp.o $(obj)/gen-hyprel FORCE
 70	$(call if_changed,hyprel)
 71
 72# 5) Compile hyp-reloc.S and link it into the existing partially linked object.
 73#    The object file now contains a section with pointers to hyp positions that
 74#    will contain kernel VAs at runtime. These pointers have relocations on them
 75#    so that they get updated as the hyp object is linked into `vmlinux`.
 76LDFLAGS_kvm_nvhe.rel.o := -r
 77$(obj)/kvm_nvhe.rel.o: $(obj)/kvm_nvhe.tmp.o $(obj)/hyp-reloc.o FORCE
 78	$(call if_changed,ld)
 79
 80# 6) Produce the final 'kvm_nvhe.o', ready to be linked into 'vmlinux'.
 81#    Prefixes names of ELF symbols with '__kvm_nvhe_'.
 82$(obj)/kvm_nvhe.o: $(obj)/kvm_nvhe.rel.o FORCE
 83	$(call if_changed,hypcopy)
 84
 85# The HYPREL command calls `gen-hyprel` to generate an assembly file with
 86# a list of relocations targeting hyp code/data.
 87quiet_cmd_hyprel = HYPREL  $@
 88      cmd_hyprel = $(obj)/gen-hyprel $< > $@
 89
 90# The HYPCOPY command uses `objcopy` to prefix all ELF symbol names
 91# to avoid clashes with VHE code/data.
 92quiet_cmd_hypcopy = HYPCOPY $@
 93      cmd_hypcopy = $(OBJCOPY) --prefix-symbols=__kvm_nvhe_ $< $@
 94
 95# Remove ftrace and Shadow Call Stack CFLAGS.
 96# This is equivalent to the 'notrace' and '__noscs' annotations.
 97KBUILD_CFLAGS := $(filter-out $(CC_FLAGS_FTRACE) $(CC_FLAGS_SCS), $(KBUILD_CFLAGS))
 98# Starting from 13.0.0 llvm emits SHT_REL section '.llvm.call-graph-profile'
 99# when profile optimization is applied. gen-hyprel does not support SHT_REL and
100# causes a build failure. Remove profile optimization flags.
101KBUILD_CFLAGS := $(filter-out -fprofile-sample-use=% -fprofile-use=%, $(KBUILD_CFLAGS))
102KBUILD_CFLAGS += -fno-asynchronous-unwind-tables -fno-unwind-tables
103
104ifeq ($(CONFIG_UBSAN_KVM_EL2),y)
105UBSAN_SANITIZE := y
106# Always use brk and not hooks
107ccflags-y += $(CFLAGS_UBSAN_TRAP)
108endif