This option can be used in Kconfig files to compare the ld version
and enable/disable incompatible config options if required.
This option is used in the subsequent patch along with GCC_VERSION to
filter out an incompatible feature.
Signed-off-by: Amit Daniel Kachhap <[email protected]>
---
Changes since v1:
* None.
This patch series is based on Linux arm64 for-next tree [1]. More details
of this work can be found in the thread [2].
[1]: https://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-next/core
[2]: http://lists.infradead.org/pipermail/linux-arm-kernel/2020-March/720257.html
init/Kconfig | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/init/Kconfig b/init/Kconfig
index 452bc18..68ddbcd 100644
--- a/init/Kconfig
+++ b/init/Kconfig
@@ -17,6 +17,10 @@ config GCC_VERSION
default $(shell,$(srctree)/scripts/gcc-version.sh $(CC)) if CC_IS_GCC
default 0
+config LD_VERSION
+ int
+ default $(shell,$(LD) --version | $(srctree)/scripts/ld-version.sh)
+
config CC_IS_CLANG
def_bool $(success,$(CC) --version | head -n 1 | grep -q clang)
--
2.7.4
Recent addition of ARM64_PTR_AUTH exposed a mismatch issue with binutils.
9.1+ versions of gcc inserts a section note .note.gnu.property but this
can be used properly by binutils version greater than 2.33.1. If older
binutils are used then the following warnings are generated,
aarch64-linux-ld: warning: arch/arm64/kernel/vdso/vgettimeofday.o: unsupported GNU_PROPERTY_TYPE (5) type: 0xc0000000
aarch64-linux-objdump: warning: arch/arm64/lib/csum.o: unsupported GNU_PROPERTY_TYPE (5) type: 0xc0000000
aarch64-linux-nm: warning: .tmp_vmlinux1: unsupported GNU_PROPERTY_TYPE (5) type: 0xc0000000
This patch enables ARM64_PTR_AUTH when gcc and binutils versions are
compatible with each other. Older gcc which do not insert such section
continue to work as before.
This scenario may not occur with clang as a recent commit 3b446c7d27ddd06
("arm64: Kconfig: verify binutils support for ARM64_PTR_AUTH") masks
binutils version lesser then 2.34.
Reported-by: kbuild test robot <[email protected]>
Suggested-by: Vincenzo Frascino <[email protected]>
Signed-off-by: Amit Daniel Kachhap <[email protected]>
---
Changes since v1[1]:
* Separated GCC and CLANG checks as suggested by Catalin.
* Added comments in Kconfig entry.
[1]: https://lkml.org/lkml/2020/3/26/626
arch/arm64/Kconfig | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index e6712b6..4391a4f 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -1503,7 +1503,10 @@ config ARM64_PTR_AUTH
default y
depends on !KVM || ARM64_VHE
depends on (CC_HAS_SIGN_RETURN_ADDRESS || CC_HAS_BRANCH_PROT_PAC_RET) && AS_HAS_PAC
- depends on CC_IS_GCC || (CC_IS_CLANG && AS_HAS_CFI_NEGATE_RA_STATE)
+ # GCC 9.1 version inserts a section note .note.gnu.property for PAC
+ # which can be used properly by binutils version 2.33.1 and higher.
+ depends on !CC_IS_GCC || GCC_VERSION < 90100 || LD_VERSION >= 233010000
+ depends on !CC_IS_CLANG || AS_HAS_CFI_NEGATE_RA_STATE
depends on (!FUNCTION_GRAPH_TRACER || DYNAMIC_FTRACE_WITH_REGS)
help
Pointer authentication (part of the ARMv8.3 Extensions) provides
--
2.7.4
On Mon, Mar 30, 2020 at 05:11:39PM +0530, Amit Daniel Kachhap wrote:
> Recent addition of ARM64_PTR_AUTH exposed a mismatch issue with binutils.
> 9.1+ versions of gcc inserts a section note .note.gnu.property but this
> can be used properly by binutils version greater than 2.33.1. If older
> binutils are used then the following warnings are generated,
>
> aarch64-linux-ld: warning: arch/arm64/kernel/vdso/vgettimeofday.o: unsupported GNU_PROPERTY_TYPE (5) type: 0xc0000000
> aarch64-linux-objdump: warning: arch/arm64/lib/csum.o: unsupported GNU_PROPERTY_TYPE (5) type: 0xc0000000
> aarch64-linux-nm: warning: .tmp_vmlinux1: unsupported GNU_PROPERTY_TYPE (5) type: 0xc0000000
I queued both patches for 5.7. Thanks.
--
Catalin
Hi Amit,
On Mon, Mar 30, 2020 at 1:42 PM Amit Daniel Kachhap
<[email protected]> wrote:
> This option can be used in Kconfig files to compare the ld version
> and enable/disable incompatible config options if required.
>
> This option is used in the subsequent patch along with GCC_VERSION to
> filter out an incompatible feature.
>
> Signed-off-by: Amit Daniel Kachhap <[email protected]>
> --- a/init/Kconfig
> +++ b/init/Kconfig
> @@ -17,6 +17,10 @@ config GCC_VERSION
> default $(shell,$(srctree)/scripts/gcc-version.sh $(CC)) if CC_IS_GCC
> default 0
>
> +config LD_VERSION
> + int
> + default $(shell,$(LD) --version | $(srctree)/scripts/ld-version.sh)
> +
> config CC_IS_CLANG
> def_bool $(success,$(CC) --version | head -n 1 | grep -q clang)
.config: warning: symbol value '2.01827e+11' invalid for LD_VERSION
Seen with the or32 compiler on kisskb, e.g.
http://kisskb.ellerman.id.au/kisskb/buildresult/14226173/
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- [email protected]
In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds
On Mon, May 04, 2020 at 09:11:12AM +0200, Geert Uytterhoeven wrote:
> On Mon, Mar 30, 2020 at 1:42 PM Amit Daniel Kachhap
> <[email protected]> wrote:
> > This option can be used in Kconfig files to compare the ld version
> > and enable/disable incompatible config options if required.
> >
> > This option is used in the subsequent patch along with GCC_VERSION to
> > filter out an incompatible feature.
> >
> > Signed-off-by: Amit Daniel Kachhap <[email protected]>
>
> > --- a/init/Kconfig
> > +++ b/init/Kconfig
> > @@ -17,6 +17,10 @@ config GCC_VERSION
> > default $(shell,$(srctree)/scripts/gcc-version.sh $(CC)) if CC_IS_GCC
> > default 0
> >
> > +config LD_VERSION
> > + int
> > + default $(shell,$(LD) --version | $(srctree)/scripts/ld-version.sh)
> > +
> > config CC_IS_CLANG
> > def_bool $(success,$(CC) --version | head -n 1 | grep -q clang)
>
> .config: warning: symbol value '2.01827e+11' invalid for LD_VERSION
>
> Seen with the or32 compiler on kisskb, e.g.
> http://kisskb.ellerman.id.au/kisskb/buildresult/14226173/
Hmm. The binutils version there is '2.26.20160125', but I think
scripts/ld-version.sh is expecting that to be '2.26.0.20160125' as it would
then ignore the date suffix as of commit 0d61ed17dd30 ("ld-version: Drop
the 4th and 5th version components"). On a 32-bit host architecture, the
awk expression ends up printing the version using exponential notation,
but even on a 64-bit arch the number would still be bogus.
Will
Will Deacon <[email protected]> writes:
> On Mon, May 04, 2020 at 09:11:12AM +0200, Geert Uytterhoeven wrote:
>> On Mon, Mar 30, 2020 at 1:42 PM Amit Daniel Kachhap
>> <[email protected]> wrote:
>> > This option can be used in Kconfig files to compare the ld version
>> > and enable/disable incompatible config options if required.
>> >
>> > This option is used in the subsequent patch along with GCC_VERSION to
>> > filter out an incompatible feature.
>> >
>> > Signed-off-by: Amit Daniel Kachhap <[email protected]>
>>
>> > --- a/init/Kconfig
>> > +++ b/init/Kconfig
>> > @@ -17,6 +17,10 @@ config GCC_VERSION
>> > default $(shell,$(srctree)/scripts/gcc-version.sh $(CC)) if CC_IS_GCC
>> > default 0
>> >
>> > +config LD_VERSION
>> > + int
>> > + default $(shell,$(LD) --version | $(srctree)/scripts/ld-version.sh)
>> > +
>> > config CC_IS_CLANG
>> > def_bool $(success,$(CC) --version | head -n 1 | grep -q clang)
>>
>> .config: warning: symbol value '2.01827e+11' invalid for LD_VERSION
>>
>> Seen with the or32 compiler on kisskb, e.g.
>> http://kisskb.ellerman.id.au/kisskb/buildresult/14226173/
>
> Hmm. The binutils version there is '2.26.20160125', but I think
> scripts/ld-version.sh is expecting that to be '2.26.0.20160125' as it would
> then ignore the date suffix as of commit 0d61ed17dd30 ("ld-version: Drop
> the 4th and 5th version components").
I updated the or32 compiler on kisskb to gcc 9.3.0, thanks to Arnd for
building it.
It has binutils 2.34.
cheers