# git rev-parse -q --verify 4ca3f6d71162e660e35f62700d1dd2486feb5e4c^{commit}
# git fetch -q -n -f git://gitlab.ozlabs.ibm.com/mirror/linux-stable-rc.git linux-4.9.y
error: The last gc run reported the following. Please correct the root cause
and remove .git/gc.log.
Automatic cleanup will not be performed until the file is removed.

warning: There are too many unreachable loose objects; run 'git prune' to remove them.

# git rev-parse -q --verify 4ca3f6d71162e660e35f62700d1dd2486feb5e4c^{commit}
4ca3f6d71162e660e35f62700d1dd2486feb5e4c
# git checkout -q -f -B kisskb 4ca3f6d71162e660e35f62700d1dd2486feb5e4c
# git clean -qxdf
# < git log -1
# commit 4ca3f6d71162e660e35f62700d1dd2486feb5e4c
# Author: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
# Date:   Mon Nov 19 17:26:06 2018 +0100
# 
#     Linux 4.9.138-rc1
# < /opt/cross/kisskb/br-aarch64-glibc-2016.08-613-ge98b4dd/bin/aarch64-linux-gcc --version
# < git log --format=%s --max-count=1 4ca3f6d71162e660e35f62700d1dd2486feb5e4c
# < make -s -j 80 ARCH=arm64 O=/kisskb/build/stable-rc-4.9_arm64-defconfig_arm64 CROSS_COMPILE=/opt/cross/kisskb/br-aarch64-glibc-2016.08-613-ge98b4dd/bin/aarch64-linux-  defconfig
# make -s -j 80 ARCH=arm64 O=/kisskb/build/stable-rc-4.9_arm64-defconfig_arm64 CROSS_COMPILE=/opt/cross/kisskb/br-aarch64-glibc-2016.08-613-ge98b4dd/bin/aarch64-linux-  
arch/arm64/Makefile:27: ld does not support --fix-cortex-a53-843419; kernel may be susceptible to erratum
Completed OK
# rm -rf /kisskb/build/stable-rc-4.9_arm64-defconfig_arm64
# Build took: 0:05:05.440595