# git rev-parse -q --verify 13fef872f8b33431ebb920915252cafc651092dd^{commit}
13fef872f8b33431ebb920915252cafc651092dd
already have revision, skipping fetch
# git checkout -q -f -B kisskb 13fef872f8b33431ebb920915252cafc651092dd
# git clean -qxdf
# < git log -1
# commit 13fef872f8b33431ebb920915252cafc651092dd
# Author: Michael Ellerman <mpe@ellerman.id.au>
# Date:   Mon May 20 20:55:20 2019 +1000
# 
#     selftests/powerpc: Add a test of spectre_v2 mitigations
#     
#     This test uses the PMU to count branch prediction hits/misses for a
#     known loop, and compare the result to the reported spectre v2
#     mitigation.
#     
#     This gives us a way of sanity checking that the reported mitigation is
#     actually in effect.
#     
#     Sample output for some cases, eg:
#     
#       Power9:
#         sysfs reports: 'Vulnerable'
#          PM_BR_PRED_CCACHE: result        368 running/enabled 5792777124
#         PM_BR_MPRED_CCACHE: result        319 running/enabled 5792775546
#          PM_BR_PRED_PCACHE: result 2147483281 running/enabled 5792773128
#         PM_BR_MPRED_PCACHE: result  213604201 running/enabled 5792771640
#         Miss percent 9 %
#         OK - Measured branch prediction rates match reported spectre v2 mitigation.
#     
#         sysfs reports: 'Mitigation: Indirect branch serialisation (kernel only)'
#          PM_BR_PRED_CCACHE: result        895 running/enabled 5780320920
#         PM_BR_MPRED_CCACHE: result        822 running/enabled 5780312414
#          PM_BR_PRED_PCACHE: result 2147482754 running/enabled 5780308836
#         PM_BR_MPRED_PCACHE: result  213639731 running/enabled 5780307912
#         Miss percent 9 %
#         OK - Measured branch prediction rates match reported spectre v2 mitigation.
#     
#         sysfs reports: 'Mitigation: Indirect branch cache disabled'
#          PM_BR_PRED_CCACHE: result 2147483649 running/enabled 20540186160
#         PM_BR_MPRED_CCACHE: result 2147483649 running/enabled 20540180056
#          PM_BR_PRED_PCACHE: result          0 running/enabled 20540176090
#         PM_BR_MPRED_PCACHE: result          0 running/enabled 20540174182
#         Miss percent 100 %
#         OK - Measured branch prediction rates match reported spectre v2 mitigation.
#     
#       Power8:
#         sysfs reports: 'Vulnerable'
#          PM_BR_PRED_CCACHE: result 2147483649 running/enabled 3505888142
#         PM_BR_MPRED_CCACHE: result          9 running/enabled 3505882788
#         Miss percent 0 %
#         OK - Measured branch prediction rates match reported spectre v2 mitigation.
#     
#         sysfs reports: 'Mitigation: Indirect branch cache disabled'
#          PM_BR_PRED_CCACHE: result 2147483649 running/enabled 16931421988
#         PM_BR_MPRED_CCACHE: result 2147483649 running/enabled 16931416478
#         Miss percent 100 %
#         OK - Measured branch prediction rates match reported spectre v2 mitigation.
#         success: spectre_v2
#     
#     Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
# < /opt/cross/kisskb/br-aarch64-glibc-2016.08-613-ge98b4dd/bin/aarch64-linux-gcc --version
# < /opt/cross/kisskb/br-aarch64-glibc-2016.08-613-ge98b4dd/bin/aarch64-linux-ld --version
# < git log --format=%s --max-count=1 13fef872f8b33431ebb920915252cafc651092dd
# < make -s -j 48 ARCH=arm64 O=/kisskb/build/powerpc-next_arm64-defconfig_arm64-gcc5.4 CROSS_COMPILE=/opt/cross/kisskb/br-aarch64-glibc-2016.08-613-ge98b4dd/bin/aarch64-linux-  defconfig
# make -s -j 48 ARCH=arm64 O=/kisskb/build/powerpc-next_arm64-defconfig_arm64-gcc5.4 CROSS_COMPILE=/opt/cross/kisskb/br-aarch64-glibc-2016.08-613-ge98b4dd/bin/aarch64-linux-  
arch/arm64/Makefile:27: ld does not support --fix-cortex-a53-843419; kernel may be susceptible to erratum
arch/arm64/Makefile:40: LSE atomics not supported by binutils
/kisskb/src/drivers/i2c/busses/i2c-sh_mobile.c: In function 'sh_mobile_i2c_isr':
/kisskb/src/drivers/i2c/busses/i2c-sh_mobile.c:399:26: warning: 'data' may be used uninitialized in this function [-Wmaybe-uninitialized]
   pd->msg->buf[real_pos] = data;
                          ^
/kisskb/src/drivers/i2c/busses/i2c-sh_mobile.c:372:16: note: 'data' was declared here
  unsigned char data;
                ^
/kisskb/src/net/ipv4/fib_semantics.c: In function 'fib_check_nh_v4_gw':
/kisskb/src/net/ipv4/fib_semantics.c:1027:12: warning: 'err' may be used uninitialized in this function [-Wmaybe-uninitialized]
   if (!tbl || err) {
            ^
In file included from /kisskb/src/include/linux/rwsem.h:16:0,
                 from /kisskb/src/include/linux/notifier.h:15,
                 from /kisskb/src/include/linux/clk.h:17,
                 from /kisskb/src/drivers/tty/serial/sh-sci.c:24:
/kisskb/src/drivers/tty/serial/sh-sci.c: In function 'sci_dma_rx_submit':
/kisskb/src/include/linux/spinlock.h:288:3: warning: 'flags' may be used uninitialized in this function [-Wmaybe-uninitialized]
   _raw_spin_unlock_irqrestore(lock, flags); \
   ^
/kisskb/src/drivers/tty/serial/sh-sci.c:1353:16: note: 'flags' was declared here
  unsigned long flags;
                ^
warning: same basename if the following are built as modules:
  arch/arm64/lib/crc32.ko
  lib/crc32.ko
Completed OK
# rm -rf /kisskb/build/powerpc-next_arm64-defconfig_arm64-gcc5.4
# Build took: 0:03:54.448035