On Mon, 2019-05-20 at 10:55:20 UTC, Michael Ellerman wrote: > 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. ... > > Signed-off-by: Michael Ellerman <m...@ellerman.id.au>
Applied to powerpc next. https://git.kernel.org/powerpc/c/c790c3d2b0ec5979d83451d0688d1cd07e23d8ba cheers
