From: Nathan Chancellor <nathan@kernel.org>
To: Catalin Marinas <catalin.marinas@arm.com>, Will Deacon <will@kernel.org>
Cc: Nick Desaulniers <ndesaulniers@google.com>,
linux-arm-kernel@lists.infradead.org,
linux-kernel@vger.kernel.org, clang-built-linux@googlegroups.com,
Nathan Chancellor <nathan@kernel.org>,
Arnd Bergmann <arnd@arndb.de>
Subject: [PATCH v2] arm64: Make CPU_BIG_ENDIAN depend on ld.bfd or ld.lld 13.0.0+
Date: Mon, 8 Feb 2021 17:57:20 -0700 [thread overview]
Message-ID: <20210209005719.803608-1-nathan@kernel.org> (raw)
In-Reply-To: <20210202022441.1451389-1-nathan@kernel.org>
Similar to commit 28187dc8ebd9 ("ARM: 9025/1: Kconfig: CPU_BIG_ENDIAN
depends on !LD_IS_LLD"), ld.lld prior to 13.0.0 does not properly
support aarch64 big endian, leading to the following build error when
CONFIG_CPU_BIG_ENDIAN is selected:
ld.lld: error: unknown emulation: aarch64linuxb
This has been resolved in LLVM 13. To avoid errors like this, only allow
CONFIG_CPU_BIG_ENDIAN to be selected if using ld.bfd or ld.lld 13.0.0
and newer.
While we are here, the indentation of this symbol used spaces since its
introduction in commit a872013d6d03 ("arm64: kconfig: allow
CPU_BIG_ENDIAN to be selected"). Change it to tabs to be consistent with
kernel coding style.
Link: https://github.com/ClangBuiltLinux/linux/issues/380
Link: https://github.com/ClangBuiltLinux/linux/issues/1288
Link: https://github.com/llvm/llvm-project/commit/7605a9a009b5fa3bdac07e3131c8d82f6d08feb7
Link: https://github.com/llvm/llvm-project/commit/eea34aae2e74e9b6fbdd5b95f479bc7f397bf387
Reported-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
---
v1 -> v2:
* Conditionally disable CONFIG_CPU_BIG_ENDIAN for older versions of
ld.lld now that proper support has been added to ld.lld 13+ (thanks to
the quick work of Fangrui Song).
arch/arm64/Kconfig | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index f39568b28ec1..912da4e2ab59 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -952,8 +952,9 @@ choice
that is selected here.
config CPU_BIG_ENDIAN
- bool "Build big-endian kernel"
- help
+ bool "Build big-endian kernel"
+ depends on !LD_IS_LLD || LLD_VERSION >= 130000
+ help
Say Y if you plan on running a kernel with a big-endian userspace.
config CPU_LITTLE_ENDIAN
base-commit: 92bf22614b21a2706f4993b278017e437f7785b3
--
2.30.1
WARNING: multiple messages have this Message-ID (diff)
From: Nathan Chancellor <nathan@kernel.org>
To: Catalin Marinas <catalin.marinas@arm.com>, Will Deacon <will@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>,
Nick Desaulniers <ndesaulniers@google.com>,
linux-kernel@vger.kernel.org,
Nathan Chancellor <nathan@kernel.org>,
clang-built-linux@googlegroups.com,
linux-arm-kernel@lists.infradead.org
Subject: [PATCH v2] arm64: Make CPU_BIG_ENDIAN depend on ld.bfd or ld.lld 13.0.0+
Date: Mon, 8 Feb 2021 17:57:20 -0700 [thread overview]
Message-ID: <20210209005719.803608-1-nathan@kernel.org> (raw)
In-Reply-To: <20210202022441.1451389-1-nathan@kernel.org>
Similar to commit 28187dc8ebd9 ("ARM: 9025/1: Kconfig: CPU_BIG_ENDIAN
depends on !LD_IS_LLD"), ld.lld prior to 13.0.0 does not properly
support aarch64 big endian, leading to the following build error when
CONFIG_CPU_BIG_ENDIAN is selected:
ld.lld: error: unknown emulation: aarch64linuxb
This has been resolved in LLVM 13. To avoid errors like this, only allow
CONFIG_CPU_BIG_ENDIAN to be selected if using ld.bfd or ld.lld 13.0.0
and newer.
While we are here, the indentation of this symbol used spaces since its
introduction in commit a872013d6d03 ("arm64: kconfig: allow
CPU_BIG_ENDIAN to be selected"). Change it to tabs to be consistent with
kernel coding style.
Link: https://github.com/ClangBuiltLinux/linux/issues/380
Link: https://github.com/ClangBuiltLinux/linux/issues/1288
Link: https://github.com/llvm/llvm-project/commit/7605a9a009b5fa3bdac07e3131c8d82f6d08feb7
Link: https://github.com/llvm/llvm-project/commit/eea34aae2e74e9b6fbdd5b95f479bc7f397bf387
Reported-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
---
v1 -> v2:
* Conditionally disable CONFIG_CPU_BIG_ENDIAN for older versions of
ld.lld now that proper support has been added to ld.lld 13+ (thanks to
the quick work of Fangrui Song).
arch/arm64/Kconfig | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index f39568b28ec1..912da4e2ab59 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -952,8 +952,9 @@ choice
that is selected here.
config CPU_BIG_ENDIAN
- bool "Build big-endian kernel"
- help
+ bool "Build big-endian kernel"
+ depends on !LD_IS_LLD || LLD_VERSION >= 130000
+ help
Say Y if you plan on running a kernel with a big-endian userspace.
config CPU_LITTLE_ENDIAN
base-commit: 92bf22614b21a2706f4993b278017e437f7785b3
--
2.30.1
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http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
next prev parent reply other threads:[~2021-02-09 0:59 UTC|newest]
Thread overview: 18+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-02-02 2:24 [PATCH] arm64: Make CPU_BIG_ENDIAN depend on !LD_IS_LLD Nathan Chancellor
2021-02-02 2:24 ` Nathan Chancellor
2021-02-02 8:04 ` Arnd Bergmann
2021-02-02 8:04 ` Arnd Bergmann
2021-02-02 19:51 ` Nathan Chancellor
2021-02-02 19:51 ` Nathan Chancellor
2021-02-02 20:43 ` Arnd Bergmann
2021-02-02 20:43 ` Arnd Bergmann
2021-02-03 10:08 ` Peter Smith
2021-02-03 10:08 ` Peter Smith
2021-02-07 2:30 ` Nathan Chancellor
2021-02-07 2:30 ` Nathan Chancellor
2021-02-09 0:57 ` Nathan Chancellor [this message]
2021-02-09 0:57 ` [PATCH v2] arm64: Make CPU_BIG_ENDIAN depend on ld.bfd or ld.lld 13.0.0+ Nathan Chancellor
2021-02-09 1:39 ` Nick Desaulniers
2021-02-09 1:39 ` Nick Desaulniers
2021-02-09 14:35 ` Will Deacon
2021-02-09 14:35 ` Will Deacon
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