# git rev-parse -q --verify c790c3d2b0ec5979d83451d0688d1cd07e23d8ba^{commit} c790c3d2b0ec5979d83451d0688d1cd07e23d8ba already have revision, skipping fetch # git checkout -q -f -B kisskb c790c3d2b0ec5979d83451d0688d1cd07e23d8ba # git clean -qxdf # < git log -1 # commit c790c3d2b0ec5979d83451d0688d1cd07e23d8ba # Author: Michael Ellerman # 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 # Signed-off-by: Michael Ellerman # Link: https://lore.kernel.org/r/20190520105520.22274-1-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 c790c3d2b0ec5979d83451d0688d1cd07e23d8ba # < make -s -j 120 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 120 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:38: LSE atomics not supported by binutils arch/arm64/Makefile:62: CROSS_COMPILE_COMPAT not defined or empty, the compat vDSO will not be built In file included from /kisskb/src/include/linux/list.h:9:0, from /kisskb/src/include/linux/wait.h:7, from /kisskb/src/include/linux/wait_bit.h:8, from /kisskb/src/include/linux/fs.h:6, from /kisskb/src/fs/btrfs/send.c:7: /kisskb/src/fs/btrfs/send.c: In function 'process_extent': /kisskb/src/include/linux/kernel.h:37:33: warning: 'clone_src_i_size' may be used uninitialized in this function [-Wmaybe-uninitialized] #define IS_ALIGNED(x, a) (((x) & ((typeof(x))(a) - 1)) == 0) ^ /kisskb/src/fs/btrfs/send.c:5088:6: note: 'clone_src_i_size' was declared here u64 clone_src_i_size; ^ /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; ^ 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:14, 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:1351:16: note: 'flags' was declared here unsigned long flags; ^ Completed OK # rm -rf /kisskb/build/powerpc-next_arm64-defconfig_arm64-gcc5.4 # Build took: 0:02:42.421367