# git rev-parse -q --verify 4c388a8e740d3235a194f330c8ef327deef710f6^{commit}
4c388a8e740d3235a194f330c8ef327deef710f6
already have revision, skipping fetch
# git checkout -q -f -B kisskb 4c388a8e740d3235a194f330c8ef327deef710f6
# git clean -qxdf
# < git log -1
# commit 4c388a8e740d3235a194f330c8ef327deef710f6
# Merge: e26dd976580a 7416cdc9b9c1
# Author: Linus Torvalds <torvalds@linux-foundation.org>
# Date:   Thu Nov 18 17:09:05 2021 -0800
# 
#     Merge tag 'zstd-for-linus-5.16-rc1' of git://github.com/terrelln/linux
#     
#     Pull zstd fixes from Nick Terrell:
#      "Fix stack usage on parisc & improve code size bloat
#     
#       This contains three commits:
#     
#        1. Fixes a minor unused variable warning reported by Kernel test
#           robot [0].
#     
#        2. Improves the reported code bloat (-88KB / 374KB) [1] by outlining
#           some functions that are unlikely to be used in performance
#           sensitive workloads.
#     
#        3. Fixes the reported excess stack usage on parisc [2] by removing
#           -O3 from zstd's compilation flags. -O3 triggered bugs in the
#           hppa-linux-gnu gcc-8 compiler. -O2 performance is acceptable:
#           neutral compression, about -1% decompression speed. We also reduce
#           code bloat (-105KB / 374KB).
#     
#       After this our code bloat is cut from 374KB to 105KB with gcc-11. If
#       we wanted to cut the remaining 105KB we'd likely have to trade
#       signicant performance, so I want to say that this is enough for now.
#     
#       We should be able to get further gains without sacrificing speed, but
#       that will take some significant optimization effort, and isn't
#       suitable for a quick fix. I've opened an upstream issue [3] to track
#       the code size, and try to avoid future regressions, and improve it in
#       the long term"
#     
#     Link: https://lore.kernel.org/linux-mm/202111120312.833wII4i-lkp@intel.com/T/ [0]
#     Link: https://lkml.org/lkml/2021/11/15/710 [1]
#     Link: https://lkml.org/lkml/2021/11/14/189 [2]
#     Link: https://github.com/facebook/zstd/issues/2867 [3]
#     Link: https://lore.kernel.org/r/20211117014949.1169186-1-nickrterrell@gmail.com/
#     Link: https://lore.kernel.org/r/20211117201459.1194876-1-nickrterrell@gmail.com/
#     
#     * tag 'zstd-for-linus-5.16-rc1' of git://github.com/terrelln/linux:
#       lib: zstd: Don't add -O3 to cflags
#       lib: zstd: Don't inline functions in zstd_opt.c
#       lib: zstd: Fix unused variable warning
# < /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 4c388a8e740d3235a194f330c8ef327deef710f6
# < make -s -j 24 ARCH=x86 O=/kisskb/build/linus_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 24 ARCH=x86 O=/kisskb/build/linus_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 24 ARCH=x86 O=/kisskb/build/linus_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 24 ARCH=x86 O=/kisskb/build/linus_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: __do_fast_syscall_32()+0xa: call to stackleak_track_stack() leaves .noinstr.text section
vmlinux.o: warning: objtool: do_syscall_64()+0x9: call to stackleak_track_stack() leaves .noinstr.text section
vmlinux.o: warning: objtool: do_int80_syscall_32()+0x9: call to stackleak_track_stack() leaves .noinstr.text section
vmlinux.o: warning: objtool: xen_get_debugreg()+0xb: call to HYPERVISOR_get_debugreg() leaves .noinstr.text section
vmlinux.o: warning: objtool: xen_set_debugreg()+0x15: call to HYPERVISOR_set_debugreg.isra.0() leaves .noinstr.text section
vmlinux.o: warning: objtool: exc_general_protection()+0x22: call to stackleak_track_stack() leaves .noinstr.text section
vmlinux.o: warning: objtool: fixup_bad_iret()+0x20: call to stackleak_track_stack() leaves .noinstr.text section
vmlinux.o: warning: objtool: mce_setup()+0x18: call to memset() leaves .noinstr.text section
vmlinux.o: warning: objtool: do_machine_check()+0x27: call to stackleak_track_stack() leaves .noinstr.text section
vmlinux.o: warning: objtool: .entry.text+0x10e6: call to stackleak_erase() leaves .noinstr.text section
vmlinux.o: warning: objtool: .entry.text+0x143: call to stackleak_erase() leaves .noinstr.text section
vmlinux.o: warning: objtool: .entry.text+0x17d9: call to stackleak_erase() leaves .noinstr.text section
Completed OK
# rm -rf /kisskb/build/linus_x86-allmodconfig_x86_64-gcc11
# Build took: 0:33:01.544034