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perf/x86/intel: Initialize TFA MSR

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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 <eranian@google.com>
Tested-by: Nelson DSouza <nelson.dsouza@intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: tonyj@suse.com
Link: https://lkml.kernel.org/r/20190321123849.GN6521@hirez.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This commit is contained in:
Peter Zijlstra 2019-03-21 13:38:49 +01:00 committed by Ingo Molnar
parent 583feb08e7
commit d7262457e3
1 changed files with 6 additions and 0 deletions
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6
arch/x86/events/intel/core.c
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@ -3575,6 +3575,12 @@ 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);