Commit fb0b0a73 authored by Andrew Donnellan's avatar Andrew Donnellan Committed by Michael Ellerman
Browse files

powerpc: Enable kcov 



kcov provides kernel coverage data that's useful for fuzzing tools like
syzkaller.

Wire up kcov support on powerpc. Disable kcov instrumentation on the same
files where we currently disable gcov and UBSan instrumentation, plus some
additional exclusions which appear necessary to boot on book3e machines.

Signed-off-by: default avatarAndrew Donnellan <andrew.donnellan@au1.ibm.com>
Acked-by: default avatarDmitry Vyukov <dvyukov@google.com>
Tested-by: Daniel Axtens <dja@axtens.net> # e6500
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
parent 8f54a6f7

arch/powerpc/Kconfig

+1 −0
Original line number Diff line number Diff line
@@ -130,6 +130,7 @@ config PPC 
	select ARCH_HAS_ELF_RANDOMIZE

	select ARCH_HAS_FORTIFY_SOURCE

	select ARCH_HAS_GCOV_PROFILE_ALL

	select ARCH_HAS_KCOV

	select ARCH_HAS_PHYS_TO_DMA

	select ARCH_HAS_PMEM_API                if PPC64

	select ARCH_HAS_PTE_SPECIAL

arch/powerpc/kernel/Makefile

+11 −1
Original line number Diff line number Diff line
@@ -143,19 +143,29 @@ endif 
obj-$(CONFIG_EPAPR_PARAVIRT)	+= epapr_paravirt.o epapr_hcalls.o

obj-$(CONFIG_KVM_GUEST)		+= kvm.o kvm_emul.o



# Disable GCOV & sanitizers in odd or sensitive code

# Disable GCOV, KCOV & sanitizers in odd or sensitive code

GCOV_PROFILE_prom_init.o := n

KCOV_INSTRUMENT_prom_init.o := n

UBSAN_SANITIZE_prom_init.o := n

GCOV_PROFILE_machine_kexec_64.o := n

KCOV_INSTRUMENT_machine_kexec_64.o := n

UBSAN_SANITIZE_machine_kexec_64.o := n

GCOV_PROFILE_machine_kexec_32.o := n

KCOV_INSTRUMENT_machine_kexec_32.o := n

UBSAN_SANITIZE_machine_kexec_32.o := n

GCOV_PROFILE_kprobes.o := n

KCOV_INSTRUMENT_kprobes.o := n

UBSAN_SANITIZE_kprobes.o := n

GCOV_PROFILE_kprobes-ftrace.o := n

KCOV_INSTRUMENT_kprobes-ftrace.o := n

UBSAN_SANITIZE_kprobes-ftrace.o := n

UBSAN_SANITIZE_vdso.o := n



# Necessary for booting with kcov enabled on book3e machines

KCOV_INSTRUMENT_cputable.o := n

KCOV_INSTRUMENT_setup_64.o := n

KCOV_INSTRUMENT_paca.o := n



extra-$(CONFIG_PPC_FPU)		+= fpu.o

extra-$(CONFIG_ALTIVEC)		+= vector.o

extra-$(CONFIG_PPC64)		+= entry_64.o

arch/powerpc/kernel/trace/Makefile

+2 −1
Original line number Diff line number Diff line
@@ -23,6 +23,7 @@ obj-$(CONFIG_TRACING) += trace_clock.o 
obj-$(CONFIG_PPC64)			+= $(obj64-y)

obj-$(CONFIG_PPC32)			+= $(obj32-y)



# Disable GCOV & sanitizers in odd or sensitive code

# Disable GCOV, KCOV & sanitizers in odd or sensitive code

GCOV_PROFILE_ftrace.o := n

KCOV_INSTRUMENT_ftrace.o := n

UBSAN_SANITIZE_ftrace.o := n

arch/powerpc/kernel/vdso32/Makefile

+1 −0
Original line number Diff line number Diff line
@@ -23,6 +23,7 @@ targets := $(obj-vdso32) vdso32.so vdso32.so.dbg 
obj-vdso32 := $(addprefix $(obj)/, $(obj-vdso32))



GCOV_PROFILE := n

KCOV_INSTRUMENT := n

UBSAN_SANITIZE := n



ccflags-y := -shared -fno-common -fno-builtin

arch/powerpc/kernel/vdso64/Makefile

+1 −0
Original line number Diff line number Diff line
@@ -9,6 +9,7 @@ targets := $(obj-vdso64) vdso64.so vdso64.so.dbg 
obj-vdso64 := $(addprefix $(obj)/, $(obj-vdso64))



GCOV_PROFILE := n

KCOV_INSTRUMENT := n

UBSAN_SANITIZE := n



ccflags-y := -shared -fno-common -fno-builtin

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