# git rev-parse -q --verify 2483ef056f6e42f61cd266452e2841165dfe1b5c^{commit}
2483ef056f6e42f61cd266452e2841165dfe1b5c
already have revision, skipping fetch
# git checkout -q -f -B kisskb 2483ef056f6e42f61cd266452e2841165dfe1b5c
# git clean -qxdf
# < git log -1
# commit 2483ef056f6e42f61cd266452e2841165dfe1b5c
# Author: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
# Date:   Tue Sep 25 17:55:15 2018 +0530
# 
#     powerpc/numa: Use associativity if VPHN hcall is successful
#     
#     Currently associativity is used to lookup node-id even if the
#     preceding VPHN hcall failed. However this can cause CPU to be made
#     part of the wrong node, (most likely to be node 0). This is because
#     VPHN is not enabled on KVM guests.
#     
#     With 2ea6263 ("powerpc/topology: Get topology for shared processors at
#     boot"), associativity is used to set to the wrong node. Hence KVM
#     guest topology is broken.
#     
#     For example : A 4 node KVM guest before would have reported.
#     
#       [root@localhost ~]#  numactl -H
#       available: 4 nodes (0-3)
#       node 0 cpus: 0 1 2 3
#       node 0 size: 1746 MB
#       node 0 free: 1604 MB
#       node 1 cpus: 4 5 6 7
#       node 1 size: 2044 MB
#       node 1 free: 1765 MB
#       node 2 cpus: 8 9 10 11
#       node 2 size: 2044 MB
#       node 2 free: 1837 MB
#       node 3 cpus: 12 13 14 15
#       node 3 size: 2044 MB
#       node 3 free: 1903 MB
#       node distances:
#       node   0   1   2   3
#         0:  10  40  40  40
#         1:  40  10  40  40
#         2:  40  40  10  40
#         3:  40  40  40  10
#     
#     Would now report:
#     
#       [root@localhost ~]# numactl -H
#       available: 4 nodes (0-3)
#       node 0 cpus: 0 2 3 4 5 6 7 8 9 10 11 12 13 14 15
#       node 0 size: 1746 MB
#       node 0 free: 1244 MB
#       node 1 cpus:
#       node 1 size: 2044 MB
#       node 1 free: 2032 MB
#       node 2 cpus: 1
#       node 2 size: 2044 MB
#       node 2 free: 2028 MB
#       node 3 cpus:
#       node 3 size: 2044 MB
#       node 3 free: 2032 MB
#       node distances:
#       node   0   1   2   3
#         0:  10  40  40  40
#         1:  40  10  40  40
#         2:  40  40  10  40
#         3:  40  40  40  10
#     
#     Fix this by skipping associativity lookup if the VPHN hcall failed.
#     
#     Fixes: 2ea626306810 ("powerpc/topology: Get topology for shared processors at boot")
#     Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
#     Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
# < /opt/cross/kisskb/korg/gcc-5.5.0-nolibc/powerpc64-linux/bin/powerpc64-linux-gcc --version
# < git log --format=%s --max-count=1 2483ef056f6e42f61cd266452e2841165dfe1b5c
# < make -s -j 120 ARCH=powerpc O=/kisskb/build/powerpc-fixes_44x_canyonlands_defconfig_powerpc-gcc5 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-5.5.0-nolibc/powerpc64-linux/bin/powerpc64-linux-  44x/canyonlands_defconfig
# make -s -j 120 ARCH=powerpc O=/kisskb/build/powerpc-fixes_44x_canyonlands_defconfig_powerpc-gcc5 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-5.5.0-nolibc/powerpc64-linux/bin/powerpc64-linux-  
Completed OK
# rm -rf /kisskb/build/powerpc-fixes_44x_canyonlands_defconfig_powerpc-gcc5
# Build took: 0:00:16.146006