[PATCH v4] arm64: allow building with kcov coverage on ARM64

From: Alexander Potapenko
Date: Thu Jun 16 2016 - 12:40:10 EST


Add ARCH_HAS_KCOV to ARM64 config. To avoid potential crashes, disable
instrumentation of the files in arch/arm64/kvm/hyp/*.

Signed-off-by: Alexander Potapenko <glider@xxxxxxxxxx>
Acked-by: Mark Rutland <mark.rutland@xxxxxxx>
Acked-by: Marc Zyngier <marc.zyngier@xxxxxxx>
Tested-by: James Morse <james.morse@xxxxxxx>
---
v4: - added ack from Marc Zyngier and Tested-by from James Morse
v3: - reverted arch/arm64/boot/Makefile, there's no code in that dir
- added ack from Mark Rutland
v2: - disable instrumentation of arch/arm64/{boot,kvm/hyp}
- enable instrumentation of arch/arm64/lib/delay.c
---
arch/arm64/Kconfig | 1 +
arch/arm64/kvm/hyp/Makefile | 4 ++++
2 files changed, 5 insertions(+)

diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index 5a0a691..eb0b0a0 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -7,6 +7,7 @@ config ARM64
select ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE
select ARCH_HAS_ELF_RANDOMIZE
select ARCH_HAS_GCOV_PROFILE_ALL
+ select ARCH_HAS_KCOV
select ARCH_HAS_SG_CHAIN
select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
select ARCH_USE_CMPXCHG_LOCKREF
diff --git a/arch/arm64/kvm/hyp/Makefile b/arch/arm64/kvm/hyp/Makefile
index 778d0ef..0c85feb 100644
--- a/arch/arm64/kvm/hyp/Makefile
+++ b/arch/arm64/kvm/hyp/Makefile
@@ -17,6 +17,10 @@ obj-$(CONFIG_KVM_ARM_HOST) += tlb.o
obj-$(CONFIG_KVM_ARM_HOST) += hyp-entry.o
obj-$(CONFIG_KVM_ARM_HOST) += s2-setup.o

+# KVM 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
UBSAN_SANITIZE := n
+KCOV_INSTRUMENT := n
--
2.8.0.rc3.226.g39d4020