* [RFC PATCH] powerpc: Enable kcov
@ 2019-01-15 4:20 Andrew Donnellan
2019-01-15 6:40 ` Dmitry Vyukov
2019-01-15 7:26 ` gcc 6.3 vs 8.2 " Mathieu Malaterre
0 siblings, 2 replies; 8+ messages in thread
From: Andrew Donnellan @ 2019-01-15 4:20 UTC (permalink / raw)
To: linuxppc-dev; +Cc: dja, syzkaller, dvyukov
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.
Signed-off-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
---
kcov looks like it's working okay, both kcovtrace and syzkaller seem to be
working. I did see some issues with compiling and booting kernels with gcc
6.3 and earlier versions which disappeared when I upgraded to gcc 8.2, I
need to investigate that more.
---
arch/powerpc/Kconfig | 1 +
arch/powerpc/kernel/Makefile | 7 ++++++-
arch/powerpc/kernel/trace/Makefile | 3 ++-
arch/powerpc/kernel/vdso32/Makefile | 1 +
arch/powerpc/kernel/vdso64/Makefile | 1 +
arch/powerpc/xmon/Makefile | 1 +
6 files changed, 12 insertions(+), 2 deletions(-)
diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index 2890d36eb531..d3698dae0e60 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -134,6 +134,7 @@ 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
diff --git a/arch/powerpc/kernel/Makefile b/arch/powerpc/kernel/Makefile
index cb7f0bb9ee71..961f44eabb65 100644
--- a/arch/powerpc/kernel/Makefile
+++ b/arch/powerpc/kernel/Makefile
@@ -142,16 +142,21 @@ 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
diff --git a/arch/powerpc/kernel/trace/Makefile b/arch/powerpc/kernel/trace/Makefile
index b1725ad3e13d..858503775c58 100644
--- a/arch/powerpc/kernel/trace/Makefile
+++ b/arch/powerpc/kernel/trace/Makefile
@@ -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
diff --git a/arch/powerpc/kernel/vdso32/Makefile b/arch/powerpc/kernel/vdso32/Makefile
index 50112d4473bb..ce199f6e4256 100644
--- a/arch/powerpc/kernel/vdso32/Makefile
+++ b/arch/powerpc/kernel/vdso32/Makefile
@@ -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
diff --git a/arch/powerpc/kernel/vdso64/Makefile b/arch/powerpc/kernel/vdso64/Makefile
index 69cecb346269..28e7d112aa2f 100644
--- a/arch/powerpc/kernel/vdso64/Makefile
+++ b/arch/powerpc/kernel/vdso64/Makefile
@@ -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
diff --git a/arch/powerpc/xmon/Makefile b/arch/powerpc/xmon/Makefile
index 878f9c1d3615..3050f9323254 100644
--- a/arch/powerpc/xmon/Makefile
+++ b/arch/powerpc/xmon/Makefile
@@ -5,6 +5,7 @@
subdir-ccflags-y := $(call cc-disable-warning, builtin-requires-header)
GCOV_PROFILE := n
+KCOV_INSTRUMENT := n
UBSAN_SANITIZE := n
# Disable ftrace for the entire directory
--
2.11.0
^ permalink raw reply related [flat|nested] 8+ messages in thread
* Re: [RFC PATCH] powerpc: Enable kcov
2019-01-15 4:20 [RFC PATCH] powerpc: Enable kcov Andrew Donnellan
@ 2019-01-15 6:40 ` Dmitry Vyukov
2019-01-15 8:00 ` Andrew Donnellan
2019-01-15 7:26 ` gcc 6.3 vs 8.2 " Mathieu Malaterre
1 sibling, 1 reply; 8+ messages in thread
From: Dmitry Vyukov @ 2019-01-15 6:40 UTC (permalink / raw)
To: Andrew Donnellan; +Cc: syzkaller, linuxppc-dev, Daniel Axtens
On Tue, Jan 15, 2019 at 5:20 AM Andrew Donnellan
<andrew.donnellan@au1.ibm.com> wrote:
>
> 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.
>
> Signed-off-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Hi Andrew,
The patch looks good to me. Any reason to mail it as RFC rather than
final patch?
Acked-by: Dmitry Vyukov <dvyukov@google.com>
> ---
>
> kcov looks like it's working okay, both kcovtrace and syzkaller seem to be
> working. I did see some issues with compiling and booting kernels with gcc
> 6.3 and earlier versions which disappeared when I upgraded to gcc 8.2, I
> need to investigate that more.
>
> ---
> arch/powerpc/Kconfig | 1 +
> arch/powerpc/kernel/Makefile | 7 ++++++-
> arch/powerpc/kernel/trace/Makefile | 3 ++-
> arch/powerpc/kernel/vdso32/Makefile | 1 +
> arch/powerpc/kernel/vdso64/Makefile | 1 +
> arch/powerpc/xmon/Makefile | 1 +
> 6 files changed, 12 insertions(+), 2 deletions(-)
>
> diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
> index 2890d36eb531..d3698dae0e60 100644
> --- a/arch/powerpc/Kconfig
> +++ b/arch/powerpc/Kconfig
> @@ -134,6 +134,7 @@ 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
> diff --git a/arch/powerpc/kernel/Makefile b/arch/powerpc/kernel/Makefile
> index cb7f0bb9ee71..961f44eabb65 100644
> --- a/arch/powerpc/kernel/Makefile
> +++ b/arch/powerpc/kernel/Makefile
> @@ -142,16 +142,21 @@ endif
> obj-$(CONFIG_EPAPR_PARAVIRT) += epapr_paravirt.o epapr_hcalls.o
> obj-$(CONFIG_KVM_GUEST) += kvm.o kvm_emul.o
>
> -# Disable GCOV & sanitizers in odd or sensitive code
> +# Disable GCOV, KCOV & sanitizers in odd or sensitive code
> GCOV_PROFILE_prom_init.o := n
> +KCOV_INSTRUMENT_prom_init.o := n
> UBSAN_SANITIZE_prom_init.o := n
> GCOV_PROFILE_machine_kexec_64.o := n
> +KCOV_INSTRUMENT_machine_kexec_64.o := n
> UBSAN_SANITIZE_machine_kexec_64.o := n
> GCOV_PROFILE_machine_kexec_32.o := n
> +KCOV_INSTRUMENT_machine_kexec_32.o := n
> UBSAN_SANITIZE_machine_kexec_32.o := n
> GCOV_PROFILE_kprobes.o := n
> +KCOV_INSTRUMENT_kprobes.o := n
> UBSAN_SANITIZE_kprobes.o := n
> GCOV_PROFILE_kprobes-ftrace.o := n
> +KCOV_INSTRUMENT_kprobes-ftrace.o := n
> UBSAN_SANITIZE_kprobes-ftrace.o := n
> UBSAN_SANITIZE_vdso.o := n
>
> diff --git a/arch/powerpc/kernel/trace/Makefile b/arch/powerpc/kernel/trace/Makefile
> index b1725ad3e13d..858503775c58 100644
> --- a/arch/powerpc/kernel/trace/Makefile
> +++ b/arch/powerpc/kernel/trace/Makefile
> @@ -23,6 +23,7 @@ obj-$(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
> diff --git a/arch/powerpc/kernel/vdso32/Makefile b/arch/powerpc/kernel/vdso32/Makefile
> index 50112d4473bb..ce199f6e4256 100644
> --- a/arch/powerpc/kernel/vdso32/Makefile
> +++ b/arch/powerpc/kernel/vdso32/Makefile
> @@ -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
> diff --git a/arch/powerpc/kernel/vdso64/Makefile b/arch/powerpc/kernel/vdso64/Makefile
> index 69cecb346269..28e7d112aa2f 100644
> --- a/arch/powerpc/kernel/vdso64/Makefile
> +++ b/arch/powerpc/kernel/vdso64/Makefile
> @@ -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
> diff --git a/arch/powerpc/xmon/Makefile b/arch/powerpc/xmon/Makefile
> index 878f9c1d3615..3050f9323254 100644
> --- a/arch/powerpc/xmon/Makefile
> +++ b/arch/powerpc/xmon/Makefile
> @@ -5,6 +5,7 @@
> subdir-ccflags-y := $(call cc-disable-warning, builtin-requires-header)
>
> GCOV_PROFILE := n
> +KCOV_INSTRUMENT := n
> UBSAN_SANITIZE := n
>
> # Disable ftrace for the entire directory
> --
> 2.11.0
>
> --
> You received this message because you are subscribed to the Google Groups "syzkaller" group.
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^ permalink raw reply [flat|nested] 8+ messages in thread
* gcc 6.3 vs 8.2 Re: [RFC PATCH] powerpc: Enable kcov
2019-01-15 4:20 [RFC PATCH] powerpc: Enable kcov Andrew Donnellan
2019-01-15 6:40 ` Dmitry Vyukov
@ 2019-01-15 7:26 ` Mathieu Malaterre
2019-01-15 8:14 ` Andrew Donnellan
2019-01-15 22:39 ` Christophe Leroy
1 sibling, 2 replies; 8+ messages in thread
From: Mathieu Malaterre @ 2019-01-15 7:26 UTC (permalink / raw)
To: Andrew Donnellan; +Cc: linuxppc-dev
[Sorry to hijack this thread. ]
On Tue, Jan 15, 2019 at 5:22 AM Andrew Donnellan
<andrew.donnellan@au1.ibm.com> wrote:
>
> 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.
>
> Signed-off-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
>
> ---
>
> kcov looks like it's working okay, both kcovtrace and syzkaller seem to be
> working. I did see some issues with compiling and booting kernels with gcc
> 6.3 and earlier versions which disappeared when I upgraded to gcc 8.2, I
> need to investigate that more.
This is also my setup. Would you be able to tell why I get a kconfig
option loop when using gcc 8.2 which I cannot reproduce using gcc 6.3
?
gcc 6-3 is ok doing:
$ make ARCH=powerpc custom_defconfig
$ make ARCH=powerpc CROSS_COMPILE=powerpc-linux-gnu-
while gcc 8.2 leads to (linux/master):
...
$ make ARCH=powerpc custom_defconfig
$ make ARCH=powerpc CROSS_COMPILE=powerpc-linux-gnu-
GEN Makefile
scripts/kconfig/conf --syncconfig Kconfig
*
* Restart config...
*
*
* General architecture-dependent options
*
OProfile system profiling (OPROFILE) [M/n/y/?] m
Kprobes (KPROBES) [Y/n/?] y
Optimize very unlikely/likely branches (JUMP_LABEL) [N/y/?] n
Stack Protector buffer overflow detection (STACKPROTECTOR) [Y/n/?] (NEW)
...
I did check that `custom_defconfig` is the minimal defconfig generated
by `savedefconfig` in both cases.
Hints or comments welcome, thanks much.
> ---
> arch/powerpc/Kconfig | 1 +
> arch/powerpc/kernel/Makefile | 7 ++++++-
> arch/powerpc/kernel/trace/Makefile | 3 ++-
> arch/powerpc/kernel/vdso32/Makefile | 1 +
> arch/powerpc/kernel/vdso64/Makefile | 1 +
> arch/powerpc/xmon/Makefile | 1 +
> 6 files changed, 12 insertions(+), 2 deletions(-)
>
> diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
> index 2890d36eb531..d3698dae0e60 100644
> --- a/arch/powerpc/Kconfig
> +++ b/arch/powerpc/Kconfig
> @@ -134,6 +134,7 @@ 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
> diff --git a/arch/powerpc/kernel/Makefile b/arch/powerpc/kernel/Makefile
> index cb7f0bb9ee71..961f44eabb65 100644
> --- a/arch/powerpc/kernel/Makefile
> +++ b/arch/powerpc/kernel/Makefile
> @@ -142,16 +142,21 @@ 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
>
> diff --git a/arch/powerpc/kernel/trace/Makefile b/arch/powerpc/kernel/trace/Makefile
> index b1725ad3e13d..858503775c58 100644
> --- a/arch/powerpc/kernel/trace/Makefile
> +++ b/arch/powerpc/kernel/trace/Makefile
> @@ -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
> diff --git a/arch/powerpc/kernel/vdso32/Makefile b/arch/powerpc/kernel/vdso32/Makefile
> index 50112d4473bb..ce199f6e4256 100644
> --- a/arch/powerpc/kernel/vdso32/Makefile
> +++ b/arch/powerpc/kernel/vdso32/Makefile
> @@ -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
> diff --git a/arch/powerpc/kernel/vdso64/Makefile b/arch/powerpc/kernel/vdso64/Makefile
> index 69cecb346269..28e7d112aa2f 100644
> --- a/arch/powerpc/kernel/vdso64/Makefile
> +++ b/arch/powerpc/kernel/vdso64/Makefile
> @@ -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
> diff --git a/arch/powerpc/xmon/Makefile b/arch/powerpc/xmon/Makefile
> index 878f9c1d3615..3050f9323254 100644
> --- a/arch/powerpc/xmon/Makefile
> +++ b/arch/powerpc/xmon/Makefile
> @@ -5,6 +5,7 @@
> subdir-ccflags-y := $(call cc-disable-warning, builtin-requires-header)
>
> GCOV_PROFILE := n
> +KCOV_INSTRUMENT := n
> UBSAN_SANITIZE := n
>
> # Disable ftrace for the entire directory
> --
> 2.11.0
>
^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [RFC PATCH] powerpc: Enable kcov
2019-01-15 6:40 ` Dmitry Vyukov
@ 2019-01-15 8:00 ` Andrew Donnellan
0 siblings, 0 replies; 8+ messages in thread
From: Andrew Donnellan @ 2019-01-15 8:00 UTC (permalink / raw)
To: Dmitry Vyukov; +Cc: syzkaller, linuxppc-dev, Daniel Axtens
On 15/1/19 5:40 pm, Dmitry Vyukov wrote:
> On Tue, Jan 15, 2019 at 5:20 AM Andrew Donnellan
> <andrew.donnellan@au1.ibm.com> wrote:
>>
>> 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.
>>
>> Signed-off-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
>
> Hi Andrew,
>
> The patch looks good to me. Any reason to mail it as RFC rather than
> final patch?
>
> Acked-by: Dmitry Vyukov <dvyukov@google.com>
Thanks!
Just the issues mentioned below, but if mpe feels like merging it anyway...
Andrew
>
>> ---
>>
>> kcov looks like it's working okay, both kcovtrace and syzkaller seem to be
>> working. I did see some issues with compiling and booting kernels with gcc
>> 6.3 and earlier versions which disappeared when I upgraded to gcc 8.2, I
>> need to investigate that more.
>>
>> ---
>> arch/powerpc/Kconfig | 1 +
>> arch/powerpc/kernel/Makefile | 7 ++++++-
>> arch/powerpc/kernel/trace/Makefile | 3 ++-
>> arch/powerpc/kernel/vdso32/Makefile | 1 +
>> arch/powerpc/kernel/vdso64/Makefile | 1 +
>> arch/powerpc/xmon/Makefile | 1 +
>> 6 files changed, 12 insertions(+), 2 deletions(-)
>>
>> diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
>> index 2890d36eb531..d3698dae0e60 100644
>> --- a/arch/powerpc/Kconfig
>> +++ b/arch/powerpc/Kconfig
>> @@ -134,6 +134,7 @@ 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
>> diff --git a/arch/powerpc/kernel/Makefile b/arch/powerpc/kernel/Makefile
>> index cb7f0bb9ee71..961f44eabb65 100644
>> --- a/arch/powerpc/kernel/Makefile
>> +++ b/arch/powerpc/kernel/Makefile
>> @@ -142,16 +142,21 @@ endif
>> obj-$(CONFIG_EPAPR_PARAVIRT) += epapr_paravirt.o epapr_hcalls.o
>> obj-$(CONFIG_KVM_GUEST) += kvm.o kvm_emul.o
>>
>> -# Disable GCOV & sanitizers in odd or sensitive code
>> +# Disable GCOV, KCOV & sanitizers in odd or sensitive code
>> GCOV_PROFILE_prom_init.o := n
>> +KCOV_INSTRUMENT_prom_init.o := n
>> UBSAN_SANITIZE_prom_init.o := n
>> GCOV_PROFILE_machine_kexec_64.o := n
>> +KCOV_INSTRUMENT_machine_kexec_64.o := n
>> UBSAN_SANITIZE_machine_kexec_64.o := n
>> GCOV_PROFILE_machine_kexec_32.o := n
>> +KCOV_INSTRUMENT_machine_kexec_32.o := n
>> UBSAN_SANITIZE_machine_kexec_32.o := n
>> GCOV_PROFILE_kprobes.o := n
>> +KCOV_INSTRUMENT_kprobes.o := n
>> UBSAN_SANITIZE_kprobes.o := n
>> GCOV_PROFILE_kprobes-ftrace.o := n
>> +KCOV_INSTRUMENT_kprobes-ftrace.o := n
>> UBSAN_SANITIZE_kprobes-ftrace.o := n
>> UBSAN_SANITIZE_vdso.o := n
>>
>> diff --git a/arch/powerpc/kernel/trace/Makefile b/arch/powerpc/kernel/trace/Makefile
>> index b1725ad3e13d..858503775c58 100644
>> --- a/arch/powerpc/kernel/trace/Makefile
>> +++ b/arch/powerpc/kernel/trace/Makefile
>> @@ -23,6 +23,7 @@ obj-$(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
>> diff --git a/arch/powerpc/kernel/vdso32/Makefile b/arch/powerpc/kernel/vdso32/Makefile
>> index 50112d4473bb..ce199f6e4256 100644
>> --- a/arch/powerpc/kernel/vdso32/Makefile
>> +++ b/arch/powerpc/kernel/vdso32/Makefile
>> @@ -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
>> diff --git a/arch/powerpc/kernel/vdso64/Makefile b/arch/powerpc/kernel/vdso64/Makefile
>> index 69cecb346269..28e7d112aa2f 100644
>> --- a/arch/powerpc/kernel/vdso64/Makefile
>> +++ b/arch/powerpc/kernel/vdso64/Makefile
>> @@ -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
>> diff --git a/arch/powerpc/xmon/Makefile b/arch/powerpc/xmon/Makefile
>> index 878f9c1d3615..3050f9323254 100644
>> --- a/arch/powerpc/xmon/Makefile
>> +++ b/arch/powerpc/xmon/Makefile
>> @@ -5,6 +5,7 @@
>> subdir-ccflags-y := $(call cc-disable-warning, builtin-requires-header)
>>
>> GCOV_PROFILE := n
>> +KCOV_INSTRUMENT := n
>> UBSAN_SANITIZE := n
>>
>> # Disable ftrace for the entire directory
>> --
>> 2.11.0
>>
>> --
>> You received this message because you are subscribed to the Google Groups "syzkaller" group.
>> To unsubscribe from this group and stop receiving emails from it, send an email to syzkaller+unsubscribe@googlegroups.com.
>> For more options, visit https://groups.google.com/d/optout.
>
--
Andrew Donnellan OzLabs, ADL Canberra
andrew.donnellan@au1.ibm.com IBM Australia Limited
^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: gcc 6.3 vs 8.2 Re: [RFC PATCH] powerpc: Enable kcov
2019-01-15 7:26 ` gcc 6.3 vs 8.2 " Mathieu Malaterre
@ 2019-01-15 8:14 ` Andrew Donnellan
2019-01-15 22:39 ` Christophe Leroy
1 sibling, 0 replies; 8+ messages in thread
From: Andrew Donnellan @ 2019-01-15 8:14 UTC (permalink / raw)
To: Mathieu Malaterre; +Cc: linuxppc-dev
On 15/1/19 6:26 pm, Mathieu Malaterre wrote:
> [Sorry to hijack this thread. ]
>
> On Tue, Jan 15, 2019 at 5:22 AM Andrew Donnellan
> <andrew.donnellan@au1.ibm.com> wrote:
>>
>> 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.
>>
>> Signed-off-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
>>
>> ---
>>
>> kcov looks like it's working okay, both kcovtrace and syzkaller seem to be
>> working. I did see some issues with compiling and booting kernels with gcc
>> 6.3 and earlier versions which disappeared when I upgraded to gcc 8.2, I
>> need to investigate that more.
>
> This is also my setup. Would you be able to tell why I get a kconfig
> option loop when using gcc 8.2 which I cannot reproduce using gcc 6.3
> ?
>
> gcc 6-3 is ok doing:
>
> $ make ARCH=powerpc custom_defconfig
> $ make ARCH=powerpc CROSS_COMPILE=powerpc-linux-gnu-
>
> while gcc 8.2 leads to (linux/master):
>
> ...
> $ make ARCH=powerpc custom_defconfig
> $ make ARCH=powerpc CROSS_COMPILE=powerpc-linux-gnu-
> GEN Makefile
> scripts/kconfig/conf --syncconfig Kconfig
> *
> * Restart config...
> *
> *
> * General architecture-dependent options
> *
> OProfile system profiling (OPROFILE) [M/n/y/?] m
> Kprobes (KPROBES) [Y/n/?] y
> Optimize very unlikely/likely branches (JUMP_LABEL) [N/y/?] n
> Stack Protector buffer overflow detection (STACKPROTECTOR) [Y/n/?] (NEW)
> ...
>
> I did check that `custom_defconfig` is the minimal defconfig generated
> by `savedefconfig` in both cases.
>
> Hints or comments welcome, thanks much.
That would be because in arch/powerpc/Kconfig:
select HAVE_STACKPROTECTOR if PPC64 &&
$(cc-option,-mstack-protector-guard=tls -mstack-protector-guard-reg=r13)
Thus the STACKPROTECTOR option appears or disappears depending on
compiler version.
Sure enough, gcc 6 whinges about that option, gcc 8 does not.
Andrew
>
>> ---
>> arch/powerpc/Kconfig | 1 +
>> arch/powerpc/kernel/Makefile | 7 ++++++-
>> arch/powerpc/kernel/trace/Makefile | 3 ++-
>> arch/powerpc/kernel/vdso32/Makefile | 1 +
>> arch/powerpc/kernel/vdso64/Makefile | 1 +
>> arch/powerpc/xmon/Makefile | 1 +
>> 6 files changed, 12 insertions(+), 2 deletions(-)
>>
>> diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
>> index 2890d36eb531..d3698dae0e60 100644
>> --- a/arch/powerpc/Kconfig
>> +++ b/arch/powerpc/Kconfig
>> @@ -134,6 +134,7 @@ config PPC
>> select ARCH_HAS_ELF_RANDOMIZE
>> select ARCH_HAS_FORTIFY_SOURCE
>> select ARCH_HAS_GCOV_PROFILE_ALL
>> + select ARCH_HAS_KCOV
>> select ARCH_HAS_PHYS_TO_DMA
>> select ARCH_HAS_PMEM_API if PPC64
>> select ARCH_HAS_PTE_SPECIAL
>> diff --git a/arch/powerpc/kernel/Makefile b/arch/powerpc/kernel/Makefile
>> index cb7f0bb9ee71..961f44eabb65 100644
>> --- a/arch/powerpc/kernel/Makefile
>> +++ b/arch/powerpc/kernel/Makefile
>> @@ -142,16 +142,21 @@ endif
>> obj-$(CONFIG_EPAPR_PARAVIRT) += epapr_paravirt.o epapr_hcalls.o
>> obj-$(CONFIG_KVM_GUEST) += kvm.o kvm_emul.o
>>
>> -# Disable GCOV & sanitizers in odd or sensitive code
>> +# Disable GCOV, KCOV & sanitizers in odd or sensitive code
>> GCOV_PROFILE_prom_init.o := n
>> +KCOV_INSTRUMENT_prom_init.o := n
>> UBSAN_SANITIZE_prom_init.o := n
>> GCOV_PROFILE_machine_kexec_64.o := n
>> +KCOV_INSTRUMENT_machine_kexec_64.o := n
>> UBSAN_SANITIZE_machine_kexec_64.o := n
>> GCOV_PROFILE_machine_kexec_32.o := n
>> +KCOV_INSTRUMENT_machine_kexec_32.o := n
>> UBSAN_SANITIZE_machine_kexec_32.o := n
>> GCOV_PROFILE_kprobes.o := n
>> +KCOV_INSTRUMENT_kprobes.o := n
>> UBSAN_SANITIZE_kprobes.o := n
>> GCOV_PROFILE_kprobes-ftrace.o := n
>> +KCOV_INSTRUMENT_kprobes-ftrace.o := n
>> UBSAN_SANITIZE_kprobes-ftrace.o := n
>> UBSAN_SANITIZE_vdso.o := n
>>
>> diff --git a/arch/powerpc/kernel/trace/Makefile b/arch/powerpc/kernel/trace/Makefile
>> index b1725ad3e13d..858503775c58 100644
>> --- a/arch/powerpc/kernel/trace/Makefile
>> +++ b/arch/powerpc/kernel/trace/Makefile
>> @@ -23,6 +23,7 @@ obj-$(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
>> diff --git a/arch/powerpc/kernel/vdso32/Makefile b/arch/powerpc/kernel/vdso32/Makefile
>> index 50112d4473bb..ce199f6e4256 100644
>> --- a/arch/powerpc/kernel/vdso32/Makefile
>> +++ b/arch/powerpc/kernel/vdso32/Makefile
>> @@ -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
>> diff --git a/arch/powerpc/kernel/vdso64/Makefile b/arch/powerpc/kernel/vdso64/Makefile
>> index 69cecb346269..28e7d112aa2f 100644
>> --- a/arch/powerpc/kernel/vdso64/Makefile
>> +++ b/arch/powerpc/kernel/vdso64/Makefile
>> @@ -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
>> diff --git a/arch/powerpc/xmon/Makefile b/arch/powerpc/xmon/Makefile
>> index 878f9c1d3615..3050f9323254 100644
>> --- a/arch/powerpc/xmon/Makefile
>> +++ b/arch/powerpc/xmon/Makefile
>> @@ -5,6 +5,7 @@
>> subdir-ccflags-y := $(call cc-disable-warning, builtin-requires-header)
>>
>> GCOV_PROFILE := n
>> +KCOV_INSTRUMENT := n
>> UBSAN_SANITIZE := n
>>
>> # Disable ftrace for the entire directory
>> --
>> 2.11.0
>>
>
--
Andrew Donnellan OzLabs, ADL Canberra
andrew.donnellan@au1.ibm.com IBM Australia Limited
^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: gcc 6.3 vs 8.2 Re: [RFC PATCH] powerpc: Enable kcov
2019-01-15 7:26 ` gcc 6.3 vs 8.2 " Mathieu Malaterre
2019-01-15 8:14 ` Andrew Donnellan
@ 2019-01-15 22:39 ` Christophe Leroy
2019-01-16 5:08 ` Michael Ellerman
1 sibling, 1 reply; 8+ messages in thread
From: Christophe Leroy @ 2019-01-15 22:39 UTC (permalink / raw)
To: Mathieu Malaterre, Andrew Donnellan; +Cc: linuxppc-dev
Le 15/01/2019 à 08:26, Mathieu Malaterre a écrit :
> [Sorry to hijack this thread. ]
>
> On Tue, Jan 15, 2019 at 5:22 AM Andrew Donnellan
> <andrew.donnellan@au1.ibm.com> wrote:
>>
>> 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.
>>
>> Signed-off-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
>>
>> ---
>>
>> kcov looks like it's working okay, both kcovtrace and syzkaller seem to be
>> working. I did see some issues with compiling and booting kernels with gcc
>> 6.3 and earlier versions which disappeared when I upgraded to gcc 8.2, I
>> need to investigate that more.
>
> This is also my setup. Would you be able to tell why I get a kconfig
> option loop when using gcc 8.2 which I cannot reproduce using gcc 6.3
> ?
>
> gcc 6-3 is ok doing:
>
> $ make ARCH=powerpc custom_defconfig
> $ make ARCH=powerpc CROSS_COMPILE=powerpc-linux-gnu-
>
> while gcc 8.2 leads to (linux/master):
>
> ...
> $ make ARCH=powerpc custom_defconfig
> $ make ARCH=powerpc CROSS_COMPILE=powerpc-linux-gnu-
> GEN Makefile
> scripts/kconfig/conf --syncconfig Kconfig
> *
> * Restart config...
> *
> *
> * General architecture-dependent options
> *
> OProfile system profiling (OPROFILE) [M/n/y/?] m
> Kprobes (KPROBES) [Y/n/?] y
> Optimize very unlikely/likely branches (JUMP_LABEL) [N/y/?] n
> Stack Protector buffer overflow detection (STACKPROTECTOR) [Y/n/?] (NEW)
> ...
>
> I did check that `custom_defconfig` is the minimal defconfig generated
> by `savedefconfig` in both cases.
>
> Hints or comments welcome, thanks much.
I think you should do:
make ARCH=powerpc CROSS_COMPILE=powerpc-linux-gnu- custom_defconfig
make ARCH=powerpc CROSS_COMPILE=powerpc-linux-gnu-
Christophe
>
>> ---
>> arch/powerpc/Kconfig | 1 +
>> arch/powerpc/kernel/Makefile | 7 ++++++-
>> arch/powerpc/kernel/trace/Makefile | 3 ++-
>> arch/powerpc/kernel/vdso32/Makefile | 1 +
>> arch/powerpc/kernel/vdso64/Makefile | 1 +
>> arch/powerpc/xmon/Makefile | 1 +
>> 6 files changed, 12 insertions(+), 2 deletions(-)
>>
>> diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
>> index 2890d36eb531..d3698dae0e60 100644
>> --- a/arch/powerpc/Kconfig
>> +++ b/arch/powerpc/Kconfig
>> @@ -134,6 +134,7 @@ 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
>> diff --git a/arch/powerpc/kernel/Makefile b/arch/powerpc/kernel/Makefile
>> index cb7f0bb9ee71..961f44eabb65 100644
>> --- a/arch/powerpc/kernel/Makefile
>> +++ b/arch/powerpc/kernel/Makefile
>> @@ -142,16 +142,21 @@ 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
>>
>> diff --git a/arch/powerpc/kernel/trace/Makefile b/arch/powerpc/kernel/trace/Makefile
>> index b1725ad3e13d..858503775c58 100644
>> --- a/arch/powerpc/kernel/trace/Makefile
>> +++ b/arch/powerpc/kernel/trace/Makefile
>> @@ -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
>> diff --git a/arch/powerpc/kernel/vdso32/Makefile b/arch/powerpc/kernel/vdso32/Makefile
>> index 50112d4473bb..ce199f6e4256 100644
>> --- a/arch/powerpc/kernel/vdso32/Makefile
>> +++ b/arch/powerpc/kernel/vdso32/Makefile
>> @@ -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
>> diff --git a/arch/powerpc/kernel/vdso64/Makefile b/arch/powerpc/kernel/vdso64/Makefile
>> index 69cecb346269..28e7d112aa2f 100644
>> --- a/arch/powerpc/kernel/vdso64/Makefile
>> +++ b/arch/powerpc/kernel/vdso64/Makefile
>> @@ -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
>> diff --git a/arch/powerpc/xmon/Makefile b/arch/powerpc/xmon/Makefile
>> index 878f9c1d3615..3050f9323254 100644
>> --- a/arch/powerpc/xmon/Makefile
>> +++ b/arch/powerpc/xmon/Makefile
>> @@ -5,6 +5,7 @@
>> subdir-ccflags-y := $(call cc-disable-warning, builtin-requires-header)
>>
>> GCOV_PROFILE := n
>> +KCOV_INSTRUMENT := n
>> UBSAN_SANITIZE := n
>>
>> # Disable ftrace for the entire directory
>> --
>> 2.11.0
>>
^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: gcc 6.3 vs 8.2 Re: [RFC PATCH] powerpc: Enable kcov
2019-01-15 22:39 ` Christophe Leroy
@ 2019-01-16 5:08 ` Michael Ellerman
2019-01-16 7:54 ` Mathieu Malaterre
0 siblings, 1 reply; 8+ messages in thread
From: Michael Ellerman @ 2019-01-16 5:08 UTC (permalink / raw)
To: Christophe Leroy, Mathieu Malaterre, Andrew Donnellan; +Cc: linuxppc-dev
Christophe Leroy <christophe.leroy@c-s.fr> writes:
> Le 15/01/2019 à 08:26, Mathieu Malaterre a écrit :
...
>>
>> I did check that `custom_defconfig` is the minimal defconfig generated
>> by `savedefconfig` in both cases.
>>
>> Hints or comments welcome, thanks much.
>
> I think you should do:
>
> make ARCH=powerpc CROSS_COMPILE=powerpc-linux-gnu- custom_defconfig
> make ARCH=powerpc CROSS_COMPILE=powerpc-linux-gnu-
Yep, you definitely need to use the same compiler for configuring and
building.
cheers
^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: gcc 6.3 vs 8.2 Re: [RFC PATCH] powerpc: Enable kcov
2019-01-16 5:08 ` Michael Ellerman
@ 2019-01-16 7:54 ` Mathieu Malaterre
0 siblings, 0 replies; 8+ messages in thread
From: Mathieu Malaterre @ 2019-01-16 7:54 UTC (permalink / raw)
To: Michael Ellerman; +Cc: linuxppc-dev, Andrew Donnellan
On Wed, Jan 16, 2019 at 6:09 AM Michael Ellerman <mpe@ellerman.id.au> wrote:
>
> Christophe Leroy <christophe.leroy@c-s.fr> writes:
> > Le 15/01/2019 à 08:26, Mathieu Malaterre a écrit :
> ...
> >>
> >> I did check that `custom_defconfig` is the minimal defconfig generated
> >> by `savedefconfig` in both cases.
> >>
> >> Hints or comments welcome, thanks much.
> >
> > I think you should do:
> >
> > make ARCH=powerpc CROSS_COMPILE=powerpc-linux-gnu- custom_defconfig
> > make ARCH=powerpc CROSS_COMPILE=powerpc-linux-gnu-
>
> Yep, you definitely need to use the same compiler for configuring and
> building.
<facepalm>
That was it. Thanks for the help !
^ permalink raw reply [flat|nested] 8+ messages in thread
end of thread, other threads:[~2019-01-16 7:56 UTC | newest]
Thread overview: 8+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2019-01-15 4:20 [RFC PATCH] powerpc: Enable kcov Andrew Donnellan
2019-01-15 6:40 ` Dmitry Vyukov
2019-01-15 8:00 ` Andrew Donnellan
2019-01-15 7:26 ` gcc 6.3 vs 8.2 " Mathieu Malaterre
2019-01-15 8:14 ` Andrew Donnellan
2019-01-15 22:39 ` Christophe Leroy
2019-01-16 5:08 ` Michael Ellerman
2019-01-16 7:54 ` Mathieu Malaterre
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