[ Upstream commit d7262457e35dbe239659e62654e56f8ddb814bed ] Stephane reported that the TFA MSR is not initialized by the kernel, but the TFA bit could set by firmware or as a leftover from a kexec, which makes the state inconsistent.
Reported-by: Stephane Eranian <[email protected]> Tested-by: Nelson DSouza <[email protected]> Signed-off-by: Peter Zijlstra (Intel) <[email protected]> Cc: Alexander Shishkin <[email protected]> Cc: Arnaldo Carvalho de Melo <[email protected]> Cc: Jiri Olsa <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: Vince Weaver <[email protected]> Cc: [email protected] Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Ingo Molnar <[email protected]> Signed-off-by: Sasha Levin <[email protected]> --- arch/x86/events/intel/core.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/arch/x86/events/intel/core.c b/arch/x86/events/intel/core.c index 26432ee4590e3..f9958ad4d3353 100644 --- a/arch/x86/events/intel/core.c +++ b/arch/x86/events/intel/core.c @@ -3447,6 +3447,12 @@ static void intel_pmu_cpu_starting(int cpu) cpuc->lbr_sel = NULL; + if (x86_pmu.flags & PMU_FL_TFA) { + WARN_ON_ONCE(cpuc->tfa_shadow); + cpuc->tfa_shadow = ~0ULL; + intel_set_tfa(cpuc, false); + } + if (x86_pmu.version > 1) flip_smm_bit(&x86_pmu.attr_freeze_on_smi); -- 2.20.1
