# git rev-parse -q --verify 3e22ed88f973d538104798edfa5140769483bce1^{commit}
3e22ed88f973d538104798edfa5140769483bce1
already have revision, skipping fetch
# git checkout -q -f -B kisskb 3e22ed88f973d538104798edfa5140769483bce1
# git clean -qxdf
# < git log -1
# commit 3e22ed88f973d538104798edfa5140769483bce1
# Author: Nicholas Piggin <npiggin@gmail.com>
# Date:   Wed Jul 25 19:54:28 2018 +1000
# 
#     powerpc/64s: free page table caches at exit_mmap time
#     
#     The kernel page table caches are tied to init_mm, so there is no
#     more need for them after userspace is finished.
#     
#     destroy_context() gets called when we drop the last reference for an
#     mm, which can be much later than the task exit due to other lazy mm
#     references to it. We can free the page table cache pages on task exit
#     because they only cache the userspace page tables and kernel threads
#     should not access user space addresses.
#     
#     The mapping for kernel threads itself is maintained in init_mm and
#     page table cache for that is attached to init_mm.
#     
#     Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
#     Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
#     [mpe: Merge change log additions from Aneesh]
#     Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
# < /opt/cross/kisskb/br-sparc64-full-2016.08-613-ge98b4dd/bin/sparc64-linux-gcc --version
# < git log --format=%s --max-count=1 3e22ed88f973d538104798edfa5140769483bce1
# < make -s -j 48 ARCH=sparc64 O=/kisskb/build/powerpc-next_sparc64-defconfig_sparc64 CROSS_COMPILE=/opt/cross/kisskb/br-sparc64-full-2016.08-613-ge98b4dd/bin/sparc64-linux-  defconfig
# make -s -j 48 ARCH=sparc64 O=/kisskb/build/powerpc-next_sparc64-defconfig_sparc64 CROSS_COMPILE=/opt/cross/kisskb/br-sparc64-full-2016.08-613-ge98b4dd/bin/sparc64-linux-  
<stdin>:1332:2: warning: #warning syscall io_pgetevents not implemented [-Wcpp]
<stdin>:1335:2: warning: #warning syscall rseq not implemented [-Wcpp]
WARNING: EXPORT symbol "_mcount" [vmlinux] version generation failed, symbol will not be versioned.
WARNING: EXPORT symbol "_mcount" [vmlinux] version generation failed, symbol will not be versioned.
  kernel: arch/sparc/boot/image is ready
  kernel: arch/sparc/boot/zImage is ready
Completed OK
# rm -rf /kisskb/build/powerpc-next_sparc64-defconfig_sparc64
# Build took: 0:01:10.160072