# git rev-parse -q --verify f2748bdfe157343eb8cf910a1d89ccf2fd20100b^{commit}
f2748bdfe157343eb8cf910a1d89ccf2fd20100b
already have revision, skipping fetch
# git checkout -q -f -B kisskb f2748bdfe157343eb8cf910a1d89ccf2fd20100b
# git clean -qxdf
# < git log -1
# commit f2748bdfe157343eb8cf910a1d89ccf2fd20100b
# Author: Nicholas Piggin <npiggin@gmail.com>
# Date:   Sun Apr 1 20:36:15 2018 +1000
# 
#     powerpc/powernv: Always stop secondaries before reboot/shutdown
#     
#     Currently powernv reboot and shutdown requests just leave secondaries
#     to do their own things. This is undesirable because they can trigger
#     any number of watchdogs while waiting for reboot, but also we don't
#     know what else they might be doing -- they might be causing trouble,
#     trampling memory, etc.
#     
#     The opal scheduled flash update code already ran into watchdog problems
#     due to flashing taking a long time, and it was fixed with 2196c6f1ed
#     ("powerpc/powernv: Return secondary CPUs to firmware before FW update"),
#     which returns secondaries to opal. It's been found that regular reboots
#     can take over 10 seconds, which can result in the hard lockup watchdog
#     firing,
#     
#       reboot: Restarting system
#       [  360.038896709,5] OPAL: Reboot request...
#       Watchdog CPU:0 Hard LOCKUP
#       Watchdog CPU:44 detected Hard LOCKUP other CPUS:16
#       Watchdog CPU:16 Hard LOCKUP
#       watchdog: BUG: soft lockup - CPU#16 stuck for 3s! [swapper/16:0]
#     
#     This patch removes the special case for flash update, and calls
#     smp_send_stop in all cases before calling reboot/shutdown.
#     
#     smp_send_stop could return CPUs to OPAL, the main reason not to is
#     that the request could come from a NMI that interrupts OPAL code,
#     so re-entry to OPAL can cause a number of problems. Putting
#     secondaries into simple spin loops improves the chances of a
#     successful reboot.
#     
#     Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
#     Reviewed-by:  Vasant Hegde <hegdevasant@linux.vnet.ibm.com>
#     Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
# < /opt/cross/kisskb/gcc-5.3.0-nolibc/powerpc64-linux/bin/powerpc64-linux-gcc --version
# < git log --format=%s --max-count=1 f2748bdfe157343eb8cf910a1d89ccf2fd20100b
# < make -s -j 80 ARCH=powerpc O=/kisskb/build/powerpc-next_ppc64_defconfig_powerpc-5.3 CROSS_COMPILE=/opt/cross/kisskb/gcc-5.3.0-nolibc/powerpc64-linux/bin/powerpc64-linux-  ppc64_defconfig
# make -s -j 80 ARCH=powerpc O=/kisskb/build/powerpc-next_ppc64_defconfig_powerpc-5.3 CROSS_COMPILE=/opt/cross/kisskb/gcc-5.3.0-nolibc/powerpc64-linux/bin/powerpc64-linux-  
WARNING: modpost: Found 2 section mismatch(es).
To see full details build your kernel with:
'make CONFIG_DEBUG_SECTION_MISMATCH=y'
Completed OK
# rm -rf /kisskb/build/powerpc-next_ppc64_defconfig_powerpc-5.3
# Build took: 0:02:47.112772