# 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/korg/gcc-8.1.0-nolibc/powerpc64-linux/bin/powerpc64-linux-gcc --version # < /opt/cross/kisskb/korg/gcc-8.1.0-nolibc/powerpc64-linux/bin/powerpc64-linux-ld --version # < git log --format=%s --max-count=1 c790c3d2b0ec5979d83451d0688d1cd07e23d8ba # < make -s -j 48 ARCH=powerpc O=/kisskb/build/powerpc-next_corenet32_smp_defconfig_powerpc-gcc8 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-8.1.0-nolibc/powerpc64-linux/bin/powerpc64-linux- corenet32_smp_defconfig # make -s -j 48 ARCH=powerpc O=/kisskb/build/powerpc-next_corenet32_smp_defconfig_powerpc-gcc8 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-8.1.0-nolibc/powerpc64-linux/bin/powerpc64-linux- In file included from /kisskb/src/include/linux/acpi.h:15, from /kisskb/src/include/linux/i2c.h:13, from /kisskb/src/include/uapi/linux/fb.h:6, from /kisskb/src/include/linux/fb.h:6, from /kisskb/src/drivers/video/fbdev/fsl-diu-fb.c:20: /kisskb/src/drivers/video/fbdev/fsl-diu-fb.c: In function 'fsl_diu_ioctl': /kisskb/src/include/linux/device.h:1743:2: warning: this statement may fall through [-Wimplicit-fallthrough=] _dev_warn(dev, dev_fmt(fmt), ##__VA_ARGS__) ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ /kisskb/src/drivers/video/fbdev/fsl-diu-fb.c:1287:3: note: in expansion of macro 'dev_warn' dev_warn(info->dev, ^~~~~~~~ /kisskb/src/drivers/video/fbdev/fsl-diu-fb.c:1290:2: note: here case MFB_SET_PIXFMT: ^~~~ In file included from /kisskb/src/include/linux/acpi.h:15, from /kisskb/src/include/linux/i2c.h:13, from /kisskb/src/include/uapi/linux/fb.h:6, from /kisskb/src/include/linux/fb.h:6, from /kisskb/src/drivers/video/fbdev/fsl-diu-fb.c:20: /kisskb/src/include/linux/device.h:1743:2: warning: this statement may fall through [-Wimplicit-fallthrough=] _dev_warn(dev, dev_fmt(fmt), ##__VA_ARGS__) ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ /kisskb/src/drivers/video/fbdev/fsl-diu-fb.c:1296:3: note: in expansion of macro 'dev_warn' dev_warn(info->dev, ^~~~~~~~ /kisskb/src/drivers/video/fbdev/fsl-diu-fb.c:1299:2: note: here case MFB_GET_PIXFMT: ^~~~ INFO: Uncompressed kernel (size 0xe683a8) overlaps the address of the wrapper(0x400000) INFO: Fixing the link_address of wrapper to (0xf00000) Image Name: Linux-5.4.0-rc2-gc790c3d2b0ec Created: Wed Oct 30 22:57:38 2019 Image Type: PowerPC Linux Kernel Image (gzip compressed) Data Size: 6786463 Bytes = 6627.41 KiB = 6.47 MiB Load Address: 00000000 Entry Point: 00000000 Completed OK # rm -rf /kisskb/build/powerpc-next_corenet32_smp_defconfig_powerpc-gcc8 # Build took: 0:02:41.404151