From 7d10436ca5695661c26d2b914fab28481b800796 Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Thu, 21 Mar 2019 13:38:49 +0100 Subject: [PATCH] perf/x86/intel: Initialize TFA MSR [ 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 Tested-by: Nelson DSouza Signed-off-by: Peter Zijlstra (Intel) Cc: Alexander Shishkin Cc: Arnaldo Carvalho de Melo Cc: Jiri Olsa Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: Vince Weaver Cc: tonyj@suse.com Link: https://lkml.kernel.org/r/20190321123849.GN6521@hirez.programming.kicks-ass.net Signed-off-by: Ingo Molnar Signed-off-by: Sasha Levin --- 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 26432ee..f9958ad 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); -- 2.7.4