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| author | Xi Ruoyao <xry111@xry111.site> | 2024-06-21 10:18:40 +0800 |
|---|---|---|
| committer | Huacai Chen <chenhuacai@loongson.cn> | 2024-06-21 10:18:40 +0800 |
| commit | 120dd4118e58dbda2ddb1dcf55f3c56cdfe8cee0 (patch) | |
| tree | 4d6b57b79e9d5dd0a1a2b0d67859b6d709496da4 /arch/loongarch | |
| parent | 6ba59ff4227927d3a8530fc2973b80e94b54d58f (diff) | |
LoongArch: Only allow OBJTOOL & ORC unwinder if toolchain supports -mthin-add-sub
GAS <= 2.41 does not support generating R_LARCH_{32,64}_PCREL for
"label - ." and it generates R_LARCH_{ADD,SUB}{32,64} pairs instead.
Objtool cannot handle R_LARCH_{ADD,SUB}{32,64} pair in __jump_table
(static key implementation) and etc. so it will produce some warnings.
This is causing the kernel CI systems to complain everywhere.
For GAS we can check if -mthin-add-sub option is available to know if
R_LARCH_{32,64}_PCREL are supported.
For Clang, we require Clang >= 18 and Clang >= 17 already supports
R_LARCH_{32,64}_PCREL. But unfortunately Clang has some other issues,
so we disable objtool for Clang at present.
Note that __jump_table here is not generated by the compiler, so
-fno-jump-table is completely irrelevant for this issue.
Fixes: cb8a2ef0848c ("LoongArch: Add ORC stack unwinder support")
Closes: https://lore.kernel.org/loongarch/Zl5m1ZlVmGKitAof@yujie-X299/
Closes: https://lore.kernel.org/loongarch/ZlY1gDDPi_mNrwJ1@slm.duckdns.org/
Closes: https://lore.kernel.org/loongarch/1717478006.038663-1-hengqi@linux.alibaba.com/
Link: https://sourceware.org/git/?p=binutils-gdb.git;a=commitdiff;h=816029e06768
Link: https://github.com/llvm/llvm-project/commit/42cb3c6346fc
Signed-off-by: Xi Ruoyao <xry111@xry111.site>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Diffstat (limited to 'arch/loongarch')
| -rw-r--r-- | arch/loongarch/Kconfig | 5 | ||||
| -rw-r--r-- | arch/loongarch/Kconfig.debug | 1 |
2 files changed, 5 insertions, 1 deletions
diff --git a/arch/loongarch/Kconfig b/arch/loongarch/Kconfig index e38139c576ee..ddc042895d01 100644 --- a/arch/loongarch/Kconfig +++ b/arch/loongarch/Kconfig @@ -143,7 +143,7 @@ config LOONGARCH select HAVE_LIVEPATCH select HAVE_MOD_ARCH_SPECIFIC select HAVE_NMI - select HAVE_OBJTOOL if AS_HAS_EXPLICIT_RELOCS + select HAVE_OBJTOOL if AS_HAS_EXPLICIT_RELOCS && AS_HAS_THIN_ADD_SUB && !CC_IS_CLANG select HAVE_PCI select HAVE_PERF_EVENTS select HAVE_PERF_REGS @@ -261,6 +261,9 @@ config AS_HAS_EXPLICIT_RELOCS config AS_HAS_FCSR_CLASS def_bool $(as-instr,movfcsr2gr \$t0$(comma)\$fcsr0) +config AS_HAS_THIN_ADD_SUB + def_bool $(cc-option,-Wa$(comma)-mthin-add-sub) + config AS_HAS_LSX_EXTENSION def_bool $(as-instr,vld \$vr0$(comma)\$a0$(comma)0) diff --git a/arch/loongarch/Kconfig.debug b/arch/loongarch/Kconfig.debug index 98d60630c3d4..8b2ce5b5d43e 100644 --- a/arch/loongarch/Kconfig.debug +++ b/arch/loongarch/Kconfig.debug @@ -28,6 +28,7 @@ config UNWINDER_PROLOGUE config UNWINDER_ORC bool "ORC unwinder" + depends on HAVE_OBJTOOL select OBJTOOL help This option enables the ORC (Oops Rewind Capability) unwinder for |