# git rev-parse -q --verify 86de312343c4b56d699f8ed98aac8bdab1e94225^{commit}
86de312343c4b56d699f8ed98aac8bdab1e94225
already have revision, skipping fetch
# git checkout -q -f -B kisskb 86de312343c4b56d699f8ed98aac8bdab1e94225
# git clean -qxdf
# < git log -1
# commit 86de312343c4b56d699f8ed98aac8bdab1e94225
# Author: Nicholas Piggin <npiggin@gmail.com>
# Date:   Mon Jun 10 13:08:18 2019 +1000
# 
#     powerpc/64s/radix: Enable HAVE_ARCH_HUGE_VMAP
#     
#     This sets the HAVE_ARCH_HUGE_VMAP option, and defines the required
#     page table functions.
#     
#     This enables huge (2MB and 1GB) ioremap mappings. I don't have a
#     benchmark for this change, but huge vmap will be used by a later core
#     kernel change to enable huge vmalloc memory mappings. This improves
#     cached `git diff` performance by about 5% on a 2-node POWER9 with 32MB
#     size dentry cache hash.
#     
#       Profiling git diff dTLB misses with a vanilla kernel:
#     
#       81.75%  git      [kernel.vmlinux]    [k] __d_lookup_rcu
#        7.21%  git      [kernel.vmlinux]    [k] strncpy_from_user
#        1.77%  git      [kernel.vmlinux]    [k] find_get_entry
#        1.59%  git      [kernel.vmlinux]    [k] kmem_cache_free
#     
#                 40,168      dTLB-miss
#            0.100342754 seconds time elapsed
#     
#       With powerpc huge vmalloc:
#     
#                  2,987      dTLB-miss
#            0.095933138 seconds time elapsed
#     
#     Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
#     Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
# < /opt/cross/kisskb/gcc-4.6.3-nolibc/powerpc-linux/bin/powerpc-linux-gcc --version
# < /opt/cross/kisskb/gcc-4.6.3-nolibc/powerpc-linux/bin/powerpc-linux-ld --version
# < git log --format=%s --max-count=1 86de312343c4b56d699f8ed98aac8bdab1e94225
# < make -s -j 80 ARCH=powerpc O=/kisskb/build/powerpc-next_ppc64e_defconfig_powerpc-gcc4.6 CROSS_COMPILE=/opt/cross/kisskb/gcc-4.6.3-nolibc/powerpc-linux/bin/powerpc-linux-  ppc64e_defconfig
# make -s -j 80 ARCH=powerpc O=/kisskb/build/powerpc-next_ppc64e_defconfig_powerpc-gcc4.6 CROSS_COMPILE=/opt/cross/kisskb/gcc-4.6.3-nolibc/powerpc-linux/bin/powerpc-linux-  
/kisskb/src/kernel/printk/printk.c: In function 'devkmsg_sysctl_set_loglvl':
/kisskb/src/kernel/printk/printk.c:194:16: warning: 'old' may be used uninitialized in this function [-Wuninitialized]
/kisskb/src/net/bridge/br_netlink.c: In function 'br_afspec.isra.28':
/kisskb/src/net/bridge/br_netlink.c:652:7: warning: 'err' may be used uninitialized in this function [-Wuninitialized]
/kisskb/src/fs/proc/inode.c: In function 'proc_reg_open':
/kisskb/src/include/linux/list.h:65:12: warning: 'pdeo' may be used uninitialized in this function [-Wuninitialized]
/kisskb/src/fs/proc/inode.c:331:21: note: 'pdeo' was declared here
/kisskb/src/fs/nfsd/nfs4xdr.c: In function 'nfsd4_encode_components_esc':
/kisskb/src/fs/nfsd/nfs4xdr.c:2077:9: warning: 'str' may be used uninitialized in this function [-Wuninitialized]
/kisskb/src/fs/udf/unicode.c: In function 'udf_name_conv_char':
/kisskb/src/fs/udf/unicode.c:132:8: warning: 'c' may be used uninitialized in this function [-Wuninitialized]
/kisskb/src/drivers/tty/serial/8250/8250_core.c: In function 'univ8250_release_irq':
/kisskb/src/drivers/tty/serial/8250/8250_core.c:247:18: warning: 'i' may be used uninitialized in this function [-Wuninitialized]
/kisskb/src/drivers/tty/serial/8250/8250_core.c:227:19: note: 'i' was declared here
/kisskb/src/drivers/net/tun.c: In function 'tun_get_user':
/kisskb/src/drivers/net/tun.c:1851:30: warning: 'copylen' may be used uninitialized in this function [-Wuninitialized]
/kisskb/src/drivers/net/tun.c:1764:46: warning: 'linear' may be used uninitialized in this function [-Wuninitialized]
WARNING: vmlinux.o (.PPC.EMB.apuinfo): unexpected non-allocatable section.
Did you forget to use "ax"/"aw" in a .S file?
Note that for example <linux/init.h> contains
section definitions for use in .S files.

INFO: Uncompressed kernel (size 0xc7eed8) overlaps the address of the wrapper(0x400000)
INFO: Fixing the link_address of wrapper to (0xd00000)
Image Name:   Linux-5.2.0-rc2-g86de312343c4
Created:      Sun Jun 16 22:36:56 2019
Image Type:   PowerPC Linux Kernel Image (gzip compressed)
Data Size:    5318391 Bytes = 5193.74 KiB = 5.07 MiB
Load Address: 00000000
Entry Point:  00000000
Completed OK
# rm -rf /kisskb/build/powerpc-next_ppc64e_defconfig_powerpc-gcc4.6
# Build took: 0:01:30.317946