xref: /linux/arch/arm64/kvm/hyp/nvhe/Makefile (revision d07b43284ab356daf7ec5ae1858a16c1c7b6adab)
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/, $(lib-objs))
22
23CFLAGS_switch.nvhe.o += -Wno-override-init
24
25hyp-obj-y := timer-sr.o sysreg-sr.o debug-sr.o switch.o tlb.o hyp-init.o host.o \
26	 hyp-main.o hyp-smp.o psci-relay.o early_alloc.o page_alloc.o \
27	 cache.o setup.o mm.o mem_protect.o sys_regs.o pkvm.o stacktrace.o ffa.o
28hyp-obj-y += ../vgic-v3-sr.o ../aarch32.o ../vgic-v2-cpuif-proxy.o ../entry.o \
29	 ../fpsimd.o ../hyp-entry.o ../exception.o ../pgtable.o
30hyp-obj-$(CONFIG_LIST_HARDENED) += list_debug.o
31hyp-obj-y += $(lib-objs)
32
33##
34## Build rules for compiling nVHE hyp code
35## Output of this folder is `kvm_nvhe.o`, a partially linked object
36## file containing all nVHE hyp code and data.
37##
38
39hyp-obj := $(patsubst %.o,%.nvhe.o,$(hyp-obj-y))
40obj-y := kvm_nvhe.o
41targets += $(hyp-obj) kvm_nvhe.tmp.o kvm_nvhe.rel.o hyp.lds hyp-reloc.S hyp-reloc.o
42
43# 1) Compile all source files to `.nvhe.o` object files. The file extension
44#    avoids file name clashes for files shared with VHE.
45$(obj)/%.nvhe.o: $(src)/%.c FORCE
46	$(call if_changed_rule,cc_o_c)
47$(obj)/%.nvhe.o: $(src)/%.S FORCE
48	$(call if_changed_rule,as_o_S)
49
50# 2) Compile linker script.
51$(obj)/hyp.lds: $(src)/hyp.lds.S FORCE
52	$(call if_changed_dep,cpp_lds_S)
53
54# 3) Partially link all '.nvhe.o' files and apply the linker script.
55#    Prefixes names of ELF sections with '.hyp', eg. '.hyp.text'.
56#    Note: The following rule assumes that the 'ld' rule puts LDFLAGS before
57#          the list of dependencies to form '-T $(obj)/hyp.lds'. This is to
58#          keep the dependency on the target while avoiding an error from
59#          GNU ld if the linker script is passed to it twice.
60LDFLAGS_kvm_nvhe.tmp.o := -r -T
61$(obj)/kvm_nvhe.tmp.o: $(obj)/hyp.lds $(addprefix $(obj)/,$(hyp-obj)) FORCE
62	$(call if_changed,ld)
63
64# 4) Generate list of hyp code/data positions that need to be relocated at
65#    runtime. Because the hypervisor is part of the kernel binary, relocations
66#    produce a kernel VA. We enumerate relocations targeting hyp at build time
67#    and convert the kernel VAs at those positions to hyp VAs.
68$(obj)/hyp-reloc.S: $(obj)/kvm_nvhe.tmp.o $(obj)/gen-hyprel FORCE
69	$(call if_changed,hyprel)
70
71# 5) Compile hyp-reloc.S and link it into the existing partially linked object.
72#    The object file now contains a section with pointers to hyp positions that
73#    will contain kernel VAs at runtime. These pointers have relocations on them
74#    so that they get updated as the hyp object is linked into `vmlinux`.
75LDFLAGS_kvm_nvhe.rel.o := -r
76$(obj)/kvm_nvhe.rel.o: $(obj)/kvm_nvhe.tmp.o $(obj)/hyp-reloc.o FORCE
77	$(call if_changed,ld)
78
79# 6) Produce the final 'kvm_nvhe.o', ready to be linked into 'vmlinux'.
80#    Prefixes names of ELF symbols with '__kvm_nvhe_'.
81$(obj)/kvm_nvhe.o: $(obj)/kvm_nvhe.rel.o FORCE
82	$(call if_changed,hypcopy)
83
84# The HYPREL command calls `gen-hyprel` to generate an assembly file with
85# a list of relocations targeting hyp code/data.
86quiet_cmd_hyprel = HYPREL  $@
87      cmd_hyprel = $(obj)/gen-hyprel $< > $@
88
89# The HYPCOPY command uses `objcopy` to prefix all ELF symbol names
90# to avoid clashes with VHE code/data.
91quiet_cmd_hypcopy = HYPCOPY $@
92      cmd_hypcopy = $(OBJCOPY) --prefix-symbols=__kvm_nvhe_ $< $@
93
94# Remove ftrace and Shadow Call Stack CFLAGS.
95# This is equivalent to the 'notrace' and '__noscs' annotations.
96KBUILD_CFLAGS := $(filter-out $(CC_FLAGS_FTRACE) $(CC_FLAGS_SCS), $(KBUILD_CFLAGS))
97# Starting from 13.0.0 llvm emits SHT_REL section '.llvm.call-graph-profile'
98# when profile optimization is applied. gen-hyprel does not support SHT_REL and
99# causes a build failure. Remove profile optimization flags.
100KBUILD_CFLAGS := $(filter-out -fprofile-sample-use=% -fprofile-use=%, $(KBUILD_CFLAGS))
101KBUILD_CFLAGS += -fno-asynchronous-unwind-tables -fno-unwind-tables
102