diff options
| author | Dmitry Vyukov <dvyukov@google.com> | 2018-06-15 00:27:44 +0200 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2018-06-15 00:55:24 +0200 |
| commit | 758517202bd2e427664857c9f2aa59da36848aca (patch) | |
| tree | 550ace0c2101cf557526c0ac07c04dc2f938c7e1 | |
| parent | sched/core / kcov: avoid kcov_area during task switch (diff) | |
| download | linux-758517202bd2e427664857c9f2aa59da36848aca.tar.xz linux-758517202bd2e427664857c9f2aa59da36848aca.zip | |
arm: port KCOV to arm
KCOV is code coverage collection facility used, in particular, by
syzkaller system call fuzzer. There is some interest in using syzkaller
on arm devices. So port KCOV to arm.
On implementation level this merely declares that KCOV is supported and
disables instrumentation of 3 special cases. Reasons for disabling are
commented in code.
Tested with qemu-system-arm/vexpress-a15.
Link: http://lkml.kernel.org/r/20180511143248.112484-1-dvyukov@google.com
Signed-off-by: Dmitry Vyukov <dvyukov@google.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Abbott Liu <liuwenliang@huawei.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Koguchi Takuo <takuo.koguchi.sw@hitachi.com>
Cc: <syzkaller@googlegroups.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| -rw-r--r-- | arch/arm/Kconfig | 3 | ||||
| -rw-r--r-- | arch/arm/boot/compressed/Makefile | 3 | ||||
| -rw-r--r-- | arch/arm/kvm/hyp/Makefile | 8 | ||||
| -rw-r--r-- | arch/arm/vdso/Makefile | 3 |
4 files changed, 16 insertions, 1 deletions
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig index 2a78bdef9a24..47eb26dc2427 100644 --- a/arch/arm/Kconfig +++ b/arch/arm/Kconfig @@ -8,9 +8,10 @@ config ARM select ARCH_HAS_DEVMEM_IS_ALLOWED select ARCH_HAS_ELF_RANDOMIZE select ARCH_HAS_FORTIFY_SOURCE + select ARCH_HAS_KCOV select ARCH_HAS_PTE_SPECIAL if ARM_LPAE - select ARCH_HAS_SET_MEMORY select ARCH_HAS_PHYS_TO_DMA + select ARCH_HAS_SET_MEMORY select ARCH_HAS_STRICT_KERNEL_RWX if MMU && !XIP_KERNEL select ARCH_HAS_STRICT_MODULE_RWX if MMU select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST diff --git a/arch/arm/boot/compressed/Makefile b/arch/arm/boot/compressed/Makefile index a3c5fbcad4ab..1f5a5ffe7fcf 100644 --- a/arch/arm/boot/compressed/Makefile +++ b/arch/arm/boot/compressed/Makefile @@ -25,6 +25,9 @@ endif GCOV_PROFILE := n +# Prevents link failures: __sanitizer_cov_trace_pc() is not linked in. +KCOV_INSTRUMENT := n + # # Architecture dependencies # diff --git a/arch/arm/kvm/hyp/Makefile b/arch/arm/kvm/hyp/Makefile index 7fc0638f263a..d2b5ec9c4b92 100644 --- a/arch/arm/kvm/hyp/Makefile +++ b/arch/arm/kvm/hyp/Makefile @@ -23,3 +23,11 @@ obj-$(CONFIG_KVM_ARM_HOST) += hyp-entry.o obj-$(CONFIG_KVM_ARM_HOST) += switch.o CFLAGS_switch.o += $(CFLAGS_ARMV7VE) obj-$(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 diff --git a/arch/arm/vdso/Makefile b/arch/arm/vdso/Makefile index bb4118213fee..f4efff9d3afb 100644 --- a/arch/arm/vdso/Makefile +++ b/arch/arm/vdso/Makefile @@ -30,6 +30,9 @@ CFLAGS_vgettimeofday.o = -O2 # Disable gcov profiling for VDSO code GCOV_PROFILE := n +# Prevents link failures: __sanitizer_cov_trace_pc() is not linked in. +KCOV_INSTRUMENT := n + # Force dependency $(obj)/vdso.o : $(obj)/vdso.so |