# git rev-parse -q --verify 51c3c62b58b357e8d35e4cc32f7b4ec907426fe3^{commit}
51c3c62b58b357e8d35e4cc32f7b4ec907426fe3
already have revision, skipping fetch
# git checkout -q -f -B kisskb 51c3c62b58b357e8d35e4cc32f7b4ec907426fe3
# git clean -qxdf
# < git log -1
# commit 51c3c62b58b357e8d35e4cc32f7b4ec907426fe3
# Author: Michael Neuling <mikey@neuling.org>
# Date:   Fri Sep 14 11:14:11 2018 +1000
# 
#     powerpc: Avoid code patching freed init sections
#     
#     This stops us from doing code patching in init sections after they've
#     been freed.
#     
#     In this chain:
#       kvm_guest_init() ->
#         kvm_use_magic_page() ->
#           fault_in_pages_readable() ->
#              __get_user() ->
#                __get_user_nocheck() ->
#                  barrier_nospec();
#     
#     We have a code patching location at barrier_nospec() and
#     kvm_guest_init() is an init function. This whole chain gets inlined,
#     so when we free the init section (hence kvm_guest_init()), this code
#     goes away and hence should no longer be patched.
#     
#     We seen this as userspace memory corruption when using a memory
#     checker while doing partition migration testing on powervm (this
#     starts the code patching post migration via
#     /sys/kernel/mobility/migration). In theory, it could also happen when
#     using /sys/kernel/debug/powerpc/barrier_nospec.
#     
#     Cc: stable@vger.kernel.org # 4.13+
#     Signed-off-by: Michael Neuling <mikey@neuling.org>
#     Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
#     Reviewed-by: Christophe Leroy <christophe.leroy@c-s.fr>
#     Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
# < /opt/cross/kisskb/gcc-4.6.3-nolibc/ia64-linux/bin/ia64-linux-gcc --version
# < git log --format=%s --max-count=1 51c3c62b58b357e8d35e4cc32f7b4ec907426fe3
# < make -s -j 48 ARCH=ia64 O=/kisskb/build/powerpc-fixes_ia64-defconfig_ia64 CROSS_COMPILE=/opt/cross/kisskb/gcc-4.6.3-nolibc/ia64-linux/bin/ia64-linux-  defconfig
# make -s -j 48 ARCH=ia64 O=/kisskb/build/powerpc-fixes_ia64-defconfig_ia64 CROSS_COMPILE=/opt/cross/kisskb/gcc-4.6.3-nolibc/ia64-linux/bin/ia64-linux-  
<stdin>:1185:2: warning: #warning syscall perf_event_open not implemented [-Wcpp]
<stdin>:1239:2: warning: #warning syscall seccomp not implemented [-Wcpp]
<stdin>:1317:2: warning: #warning syscall pkey_mprotect not implemented [-Wcpp]
<stdin>:1320:2: warning: #warning syscall pkey_alloc not implemented [-Wcpp]
<stdin>:1323:2: warning: #warning syscall pkey_free not implemented [-Wcpp]
<stdin>:1326:2: warning: #warning syscall statx not implemented [-Wcpp]
<stdin>:1332:2: warning: #warning syscall io_pgetevents not implemented [-Wcpp]
<stdin>:1335:2: warning: #warning syscall rseq not implemented [-Wcpp]
/kisskb/src/kernel/cgroup/cgroup-v1.c: In function 'cgroup1_mount':
/kisskb/src/kernel/cgroup/cgroup-v1.c:1256:20: warning: 'root' may be used uninitialized in this function [-Wuninitialized]
/kisskb/src/kernel/printk/printk.c: In function 'devkmsg_sysctl_set_loglvl':
/kisskb/src/kernel/printk/printk.c:185:16: warning: 'old' may be used uninitialized in this function [-Wuninitialized]
/kisskb/src/kernel/fork.c:723:13: warning: 'task_struct_whitelist' defined but not used [-Wunused-function]
/kisskb/src/drivers/dma-buf/reservation.c: In function 'reservation_object_add_shared_fence':
/kisskb/src/drivers/dma-buf/reservation.c:208:2: warning: 'k' may be used uninitialized in this function [-Wuninitialized]
/kisskb/src/drivers/dma-buf/reservation.c:161:17: note: 'k' was declared here
/kisskb/src/mm/vmstat.c: In function 'sysctl_vm_numa_stat_handler':
/kisskb/src/mm/vmstat.c:89:5: warning: 'oldval' may be used uninitialized in this function [-Wuninitialized]
/kisskb/src/drivers/i2c/i2c-core-base.c: In function 'i2c_generic_scl_recovery':
/kisskb/src/drivers/i2c/i2c-core-base.c:235:5: warning: 'ret' may be used uninitialized in this function [-Wuninitialized]
/kisskb/src/mm/hugetlb.c: In function 'alloc_pool_huge_page':
/kisskb/src/mm/hugetlb.c:1433:5: warning: 'page' 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:341:21: note: 'pdeo' was declared here
/kisskb/src/fs/nfsd/nfs4xdr.c: In function 'nfsd4_encode_components_esc':
/kisskb/src/fs/nfsd/nfs4xdr.c:2069:9: 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]
No errors detected in 21228 functions.
  Kernel: vmlinux.gz is ready
Completed OK
# rm -rf /kisskb/build/powerpc-fixes_ia64-defconfig_ia64
# Build took: 0:01:44.761285