# git rev-parse -q --verify dad9774deaf1cf8e8f7483310dfb2690310193d2^{commit}
# git fetch -q -n -f git://fs.ozlabs.ibm.com/kernel/linus master
warning: 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 dad9774deaf1cf8e8f7483310dfb2690310193d2^{commit}
dad9774deaf1cf8e8f7483310dfb2690310193d2
# git checkout -q -f -B kisskb dad9774deaf1cf8e8f7483310dfb2690310193d2
# git clean -qxdf
# < git log -1
# commit dad9774deaf1cf8e8f7483310dfb2690310193d2
# Merge: 007034977130 13bb06f8dd42
# Author: Linus Torvalds <torvalds@linux-foundation.org>
# Date:   Wed Jun 21 12:36:34 2023 -0700
# 
#     Merge tag 'timers-urgent-2023-06-21' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
#     
#     Pull timer fix from Thomas Gleixner:
#      "A single regression fix for a regression fix:
#     
#       For a long time the tick was aligned to clock MONOTONIC so that the
#       tick event happened at a multiple of nanoseconds per tick starting
#       from clock MONOTONIC = 0.
#     
#       At some point this changed as the refined jiffies clocksource which is
#       used during boot before the TSC or other clocksources becomes usable,
#       was adjusted with a boot offset, so that time 0 is closer to the point
#       where the kernel starts.
#     
#       This broke the assumption in the tick code that when the tick setup
#       happens early on ktime_get() will return a multiple of nanoseconds per
#       tick. As a consequence applications which aligned their periodic
#       execution so that it does not collide with the tick were not longer
#       guaranteed that the tick period starts from time 0.
#     
#       The fix for this regression was to realign the tick when it is
#       initially set up to a multiple of tick periods. That works as long as
#       the underlying tick device supports periodic mode, but breaks under
#       certain conditions when the tick device supports only one shot mode.
#     
#       Depending on the offset, the alignment delta to clock MONOTONIC can
#       get in a range where the minimal programming delta of the underlying
#       clock event device is larger than the calculated delta to the next
#       tick. This results in a boot hang as the tick code tries to play catch
#       up, but as the tick never fires jiffies are not advanced so it keeps
#       trying for ever.
#     
#       Solve this by moving the tick alignement into the NOHZ / HIGHRES
#       enablement code because at that point it is guaranteed that the
#       underlying clocksource is high resolution capable and not longer
#       depending on the tick.
#     
#       This is far before user space starts, so at the point where
#       applications try to align their timers, the old behaviour of the tick
#       happening at a multiple of nanoseconds per tick starting from clock
#       MONOTONIC = 0 is restored"
#     
#     * tag 'timers-urgent-2023-06-21' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
#       tick/common: Align tick period during sched_timer setup
# < /opt/cross/kisskb/korg/gcc-8.5.0-nolibc/x86_64-linux/bin/x86_64-linux-gcc --version
# < /opt/cross/kisskb/korg/gcc-8.5.0-nolibc/x86_64-linux/bin/x86_64-linux-ld --version
# < git log --format=%s --max-count=1 dad9774deaf1cf8e8f7483310dfb2690310193d2
# make -s -j 32 ARCH=x86 O=/kisskb/build/linus_x86_64_defconfig_x86_64-gcc8 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-8.5.0-nolibc/x86_64-linux/bin/x86_64-linux-  x86_64_defconfig
# < make -s -j 32 ARCH=x86 O=/kisskb/build/linus_x86_64_defconfig_x86_64-gcc8 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-8.5.0-nolibc/x86_64-linux/bin/x86_64-linux-  help
# make -s -j 32 ARCH=x86 O=/kisskb/build/linus_x86_64_defconfig_x86_64-gcc8 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-8.5.0-nolibc/x86_64-linux/bin/x86_64-linux-  olddefconfig
# make -s -j 32 ARCH=x86 O=/kisskb/build/linus_x86_64_defconfig_x86_64-gcc8 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-8.5.0-nolibc/x86_64-linux/bin/x86_64-linux-  
Completed OK
# rm -rf /kisskb/build/linus_x86_64_defconfig_x86_64-gcc8
# Build took: 0:02:02.223282