# git rev-parse -q --verify d4c858643263cfde13f7d937eaff95c2ed87cdf1^{commit}
d4c858643263cfde13f7d937eaff95c2ed87cdf1
already have revision, skipping fetch
# git checkout -q -f -B kisskb d4c858643263cfde13f7d937eaff95c2ed87cdf1
# git clean -qxdf
# < git log -1
# commit d4c858643263cfde13f7d937eaff95c2ed87cdf1
# Author: Changbin Du <changbin.du@gmail.com>
# Date:   Tue Feb 1 09:32:57 2022 +0800
# 
#     kallsyms: ignore all local labels prefixed by '.L'
#     
#     The llvm compiler can generate lots of local labels ('.LBB', '.Ltmpxxx',
#     '.L__unnamed_xx', etc.). These symbols usually are useless for debugging.
#     And they might overlap with handwritten symbols.
#     
#     Before this change, a dumpstack shows a local symbol for epc:
#     [    0.040341][    T0] Hardware name: riscv-virtio,qemu (DT)
#     [    0.040376][    T0] epc : .LBB6_14+0x22/0x6a
#     [    0.040452][    T0]  ra : restore_all+0x12/0x6e
#     
#     The simple solution is that we can ignore all local labels prefixed by '.L'.
#     For handwritten symbols which need to be preserved should drop the '.L'
#     prefix.
#     
#     After this change, the C defined symbol is shown so we can locate the
#     problematical code immediately:
#     [    0.035795][    T0] Hardware name: riscv-virtio,qemu (DT)
#     [    0.036332][    T0] epc : trace_hardirqs_on+0x54/0x13c
#     [    0.036567][    T0]  ra : restore_all+0x12/0x6e
#     
#     Signed-off-by: Changbin Du <changbin.du@gmail.com>
#     Reviewed-by: Nathan Chancellor <nathan@kernel.org>
#     Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
#     Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
# < /opt/cross/kisskb/korg/gcc-11.1.0-nolibc/x86_64-linux/bin/x86_64-linux-gcc --version
# < /opt/cross/kisskb/korg/gcc-11.1.0-nolibc/x86_64-linux/bin/x86_64-linux-ld --version
# < git log --format=%s --max-count=1 d4c858643263cfde13f7d937eaff95c2ed87cdf1
# < make -s -j 120 ARCH=x86 O=/kisskb/build/kbuild_x86-allmodconfig_x86_64-gcc11 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-11.1.0-nolibc/x86_64-linux/bin/x86_64-linux-  allmodconfig
# Added to kconfig CONFIG_BUILD_DOCSRC=n
# Added to kconfig CONFIG_MODULE_SIG=n
# Added to kconfig CONFIG_SAMPLES=n
# < make -s -j 120 ARCH=x86 O=/kisskb/build/kbuild_x86-allmodconfig_x86_64-gcc11 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-11.1.0-nolibc/x86_64-linux/bin/x86_64-linux-  help
# make -s -j 120 ARCH=x86 O=/kisskb/build/kbuild_x86-allmodconfig_x86_64-gcc11 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-11.1.0-nolibc/x86_64-linux/bin/x86_64-linux-  olddefconfig
# make -s -j 120 ARCH=x86 O=/kisskb/build/kbuild_x86-allmodconfig_x86_64-gcc11 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-11.1.0-nolibc/x86_64-linux/bin/x86_64-linux-  
vmlinux.o: warning: objtool: mce_start()+0x5c: call to __kasan_check_write() leaves .noinstr.text section
vmlinux.o: warning: objtool: mce_gather_info()+0x5f: call to v8086_mode.constprop.0() leaves .noinstr.text section
vmlinux.o: warning: objtool: mce_read_aux()+0x8a: call to mca_msr_reg() leaves .noinstr.text section
vmlinux.o: warning: objtool: do_machine_check()+0x197: call to mce_no_way_out() leaves .noinstr.text section
vmlinux.o: warning: objtool: mce_severity_amd.constprop.0()+0xca: call to mce_severity_amd_smca() leaves .noinstr.text section
Completed OK
# rm -rf /kisskb/build/kbuild_x86-allmodconfig_x86_64-gcc11
# Build took: 0:09:22.362323