| Message ID | 1585236720-21819-2-git-send-email-amit.kachhap@arm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [1/2] init/kconfig: Add LD_VERSION Kconfig | expand |
On Thu, Mar 26, 2020 at 09:02:00PM +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 > > 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 <lkp@intel.com> > Suggested-by: Vincenzo Frascino <Vincenzo.Frascino@arm.com> > Signed-off-by: Amit Daniel Kachhap <amit.kachhap@arm.com> > --- > arch/arm64/Kconfig | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig > index e6712b6..73135da 100644 > --- a/arch/arm64/Kconfig > +++ b/arch/arm64/Kconfig > @@ -1503,7 +1503,7 @@ 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) > + depends on (CC_IS_GCC && (GCC_VERSION < 90100 || LD_VERSION >= 233010000)) || (CC_IS_CLANG && AS_HAS_CFI_NEGATE_RA_STATE) We should add some of the comments in the commit log to the Kconfig entry. I would also split this in two (equivalent to CC_IS_ implies): depends on !CC_IS_GCC || GCC_VERSION < 90100 || LD_VERSION >= 233010000 depends on !CC_IS_CLANG || AS_HAS_CFI_NEGATE_RA_STATE and add a comment above the gcc/ld version checking. (not entirely identical to the original if CC is neither of them but I don't think we have this problem)
On 3/27/20 6:25 PM, Catalin Marinas wrote: > On Thu, Mar 26, 2020 at 09:02:00PM +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 >> >> 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 <lkp@intel.com> >> Suggested-by: Vincenzo Frascino <Vincenzo.Frascino@arm.com> >> Signed-off-by: Amit Daniel Kachhap <amit.kachhap@arm.com> >> --- >> arch/arm64/Kconfig | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >> diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig >> index e6712b6..73135da 100644 >> --- a/arch/arm64/Kconfig >> +++ b/arch/arm64/Kconfig >> @@ -1503,7 +1503,7 @@ 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) >> + depends on (CC_IS_GCC && (GCC_VERSION < 90100 || LD_VERSION >= 233010000)) || (CC_IS_CLANG && AS_HAS_CFI_NEGATE_RA_STATE) > > We should add some of the comments in the commit log to the Kconfig > entry. I would also split this in two (equivalent to CC_IS_ implies): > > depends on !CC_IS_GCC || GCC_VERSION < 90100 || LD_VERSION >= 233010000 > depends on !CC_IS_CLANG || AS_HAS_CFI_NEGATE_RA_STATE > > and add a comment above the gcc/ld version checking. > > (not entirely identical to the original if CC is neither of them but I > don't think we have this problem) Re-posted v2 as per the suggestions. Thanks, Amit >
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index e6712b6..73135da 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -1503,7 +1503,7 @@ 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) + depends on (CC_IS_GCC && (GCC_VERSION < 90100 || LD_VERSION >= 233010000)) || (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
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 <lkp@intel.com> Suggested-by: Vincenzo Frascino <Vincenzo.Frascino@arm.com> Signed-off-by: Amit Daniel Kachhap <amit.kachhap@arm.com> --- arch/arm64/Kconfig | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)