xref: /openbmc/linux/arch/arm64/kvm/hyp/nvhe/Makefile (revision aebc7b0d)
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	     $(DISABLE_STACKLEAK_PLUGIN)
16
17hostprogs := gen-hyprel
18HOST_EXTRACFLAGS += -I$(objtree)/include
19
20lib-objs := clear_page.o copy_page.o memcpy.o memset.o
21lib-objs := $(addprefix ../../../lib/, $(lib-objs))
22
23hyp-obj-y := timer-sr.o sysreg-sr.o debug-sr.o switch.o tlb.o hyp-init.o host.o \
24	 hyp-main.o hyp-smp.o psci-relay.o early_alloc.o page_alloc.o \
25	 cache.o setup.o mm.o mem_protect.o sys_regs.o pkvm.o stacktrace.o ffa.o
26hyp-obj-y += ../vgic-v3-sr.o ../aarch32.o ../vgic-v2-cpuif-proxy.o ../entry.o \
27	 ../fpsimd.o ../hyp-entry.o ../exception.o ../pgtable.o
28hyp-obj-$(CONFIG_LIST_HARDENED) += list_debug.o
29hyp-obj-y += $(lib-objs)
30
31##
32## Build rules for compiling nVHE hyp code
33## Output of this folder is `kvm_nvhe.o`, a partially linked object
34## file containing all nVHE hyp code and data.
35##
36
37hyp-obj := $(patsubst %.o,%.nvhe.o,$(hyp-obj-y))
38obj-y := kvm_nvhe.o
39targets += $(hyp-obj) kvm_nvhe.tmp.o kvm_nvhe.rel.o hyp.lds hyp-reloc.S hyp-reloc.o
40
41# 1) Compile all source files to `.nvhe.o` object files. The file extension
42#    avoids file name clashes for files shared with VHE.
43$(obj)/%.nvhe.o: $(src)/%.c FORCE
44	$(call if_changed_rule,cc_o_c)
45$(obj)/%.nvhe.o: $(src)/%.S FORCE
46	$(call if_changed_rule,as_o_S)
47
48# 2) Compile linker script.
49$(obj)/hyp.lds: $(src)/hyp.lds.S FORCE
50	$(call if_changed_dep,cpp_lds_S)
51
52# 3) Partially link all '.nvhe.o' files and apply the linker script.
53#    Prefixes names of ELF sections with '.hyp', eg. '.hyp.text'.
54#    Note: The following rule assumes that the 'ld' rule puts LDFLAGS before
55#          the list of dependencies to form '-T $(obj)/hyp.lds'. This is to
56#          keep the dependency on the target while avoiding an error from
57#          GNU ld if the linker script is passed to it twice.
58LDFLAGS_kvm_nvhe.tmp.o := -r -T
59$(obj)/kvm_nvhe.tmp.o: $(obj)/hyp.lds $(addprefix $(obj)/,$(hyp-obj)) FORCE
60	$(call if_changed,ld)
61
62# 4) Generate list of hyp code/data positions that need to be relocated at
63#    runtime. Because the hypervisor is part of the kernel binary, relocations
64#    produce a kernel VA. We enumerate relocations targeting hyp at build time
65#    and convert the kernel VAs at those positions to hyp VAs.
66$(obj)/hyp-reloc.S: $(obj)/kvm_nvhe.tmp.o $(obj)/gen-hyprel FORCE
67	$(call if_changed,hyprel)
68
69# 5) Compile hyp-reloc.S and link it into the existing partially linked object.
70#    The object file now contains a section with pointers to hyp positions that
71#    will contain kernel VAs at runtime. These pointers have relocations on them
72#    so that they get updated as the hyp object is linked into `vmlinux`.
73LDFLAGS_kvm_nvhe.rel.o := -r
74$(obj)/kvm_nvhe.rel.o: $(obj)/kvm_nvhe.tmp.o $(obj)/hyp-reloc.o FORCE
75	$(call if_changed,ld)
76
77# 6) Produce the final 'kvm_nvhe.o', ready to be linked into 'vmlinux'.
78#    Prefixes names of ELF symbols with '__kvm_nvhe_'.
79$(obj)/kvm_nvhe.o: $(obj)/kvm_nvhe.rel.o FORCE
80	$(call if_changed,hypcopy)
81
82# The HYPREL command calls `gen-hyprel` to generate an assembly file with
83# a list of relocations targeting hyp code/data.
84quiet_cmd_hyprel = HYPREL  $@
85      cmd_hyprel = $(obj)/gen-hyprel $< > $@
86
87# The HYPCOPY command uses `objcopy` to prefix all ELF symbol names
88# to avoid clashes with VHE code/data.
89quiet_cmd_hypcopy = HYPCOPY $@
90      cmd_hypcopy = $(OBJCOPY) --prefix-symbols=__kvm_nvhe_ $< $@
91
92# Remove ftrace, Shadow Call Stack, and CFI CFLAGS.
93# This is equivalent to the 'notrace', '__noscs', and '__nocfi' annotations.
94KBUILD_CFLAGS := $(filter-out $(CC_FLAGS_FTRACE) $(CC_FLAGS_SCS) $(CC_FLAGS_CFI), $(KBUILD_CFLAGS))
95# Starting from 13.0.0 llvm emits SHT_REL section '.llvm.call-graph-profile'
96# when profile optimization is applied. gen-hyprel does not support SHT_REL and
97# causes a build failure. Remove profile optimization flags.
98KBUILD_CFLAGS := $(filter-out -fprofile-sample-use=% -fprofile-use=%, $(KBUILD_CFLAGS))
99KBUILD_CFLAGS += -fno-asynchronous-unwind-tables -fno-unwind-tables
100
101# KVM nVHE code is run at a different exception code with a different map, so
102# compiler instrumentation that inserts callbacks or checks into the code may
103# cause crashes. Just disable it.
104GCOV_PROFILE	:= n
105KASAN_SANITIZE	:= n
106KCSAN_SANITIZE	:= n
107UBSAN_SANITIZE	:= n
108KCOV_INSTRUMENT	:= n
109
110# Skip objtool checking for this directory because nVHE code is compiled with
111# non-standard build rules.
112OBJECT_FILES_NON_STANDARD := y
113