# git rev-parse -q --verify f5b7769eb0400ec5217a47e41148a9f816ca1f9f^{commit}
f5b7769eb0400ec5217a47e41148a9f816ca1f9f
already have revision, skipping fetch
# git checkout -q -f -B kisskb f5b7769eb0400ec5217a47e41148a9f816ca1f9f
# git clean -qxdf
# < git log -1
# commit f5b7769eb0400ec5217a47e41148a9f816ca1f9f
# Author: Linus Torvalds <torvalds@linux-foundation.org>
# Date:   Tue Jun 12 20:52:16 2018 -0700
# 
#     Revert "debugfs: inode: debugfs_create_dir uses mode permission from parent"
#     
#     This reverts commit 95cde3c59966f6371b6bcd9e4e2da2ba64ee9775.
#     
#     The commit had good intentions, but it breaks kvm-tool and qemu-kvm.
#     
#     With it in place, "lkvm run" just fails with
#     
#       Error: KVM_CREATE_VM ioctl
#       Warning: Failed init: kvm__init
#     
#     which isn't a wonderful error message, but bisection pinpointed the
#     problematic commit.
#     
#     The problem is almost certainly due to the special kvm debugfs entries
#     created dynamically by kvm under /sys/kernel/debug/kvm/.  See
#     kvm_create_vm_debugfs()
#     
#     Bisected-and-reported-by: Linus Torvalds <torvalds@linux-foundation.org>
#     Cc: Wanpeng Li <kernellwp@gmail.com>
#     Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
#     Cc: Thomas Richter <tmricht@linux.ibm.com>
#     Cc: Kees Cook <keescook@chromium.org>
#     Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
# < /opt/cross/kisskb/fe-x86-64-core-i7-2017.05/bin/x86_64-linux-gcc --version
# < git log --format=%s --max-count=1 f5b7769eb0400ec5217a47e41148a9f816ca1f9f
# < make -s -j 10 ARCH=um O=/kisskb/build/linus_um-defconfig_um-x86_64 CROSS_COMPILE=/opt/cross/kisskb/fe-x86-64-core-i7-2017.05/bin/x86_64-linux- SUBARCH=x86_64 defconfig
# make -s -j 10 ARCH=um O=/kisskb/build/linus_um-defconfig_um-x86_64 CROSS_COMPILE=/opt/cross/kisskb/fe-x86-64-core-i7-2017.05/bin/x86_64-linux- SUBARCH=x86_64 
/kisskb/src/arch/um/os-Linux/skas/process.c: In function 'start_idle_thread':
/kisskb/src/arch/um/os-Linux/skas/process.c:613:1: warning: control reaches end of non-void function [-Wreturn-type]
 }
 ^
/kisskb/src/net/core/rtnetlink.c: In function 'rtnl_newlink':
/kisskb/src/net/core/rtnetlink.c:3099:1: warning: the frame size of 1280 bytes is larger than 1024 bytes [-Wframe-larger-than=]
 }
 ^
  LINK linux
Completed OK
# rm -rf /kisskb/build/linus_um-defconfig_um-x86_64
# Build took: 0:00:49.280445