Don't leave the tsc-early clocksource registered if it errors out early. This was reported by Diego, who on his Core2 era machine got TSC invalidated while it was running with tsc-early (due to C-states). This results in keeping tsc-early with very bad effects. Reported-and-Tested-by: Diego Viola Fixes: aa83c45762a2 ("x86/tsc: Introduce early tsc clocksource") Cc: stable@kernel.org Signed-off-by: Peter Zijlstra (Intel) --- arch/x86/kernel/tsc.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) --- a/arch/x86/kernel/tsc.c +++ b/arch/x86/kernel/tsc.c @@ -1244,7 +1244,7 @@ static void tsc_refine_calibration_work( /* Don't bother refining TSC on unstable systems */ if (tsc_unstable) - return; + goto unreg; /* * Since the work is started early in boot, we may be @@ -1297,11 +1297,12 @@ static void tsc_refine_calibration_work( out: if (tsc_unstable) - return; + goto unreg; if (boot_cpu_has(X86_FEATURE_ART)) art_related_clocksource = &clocksource_tsc; clocksource_register_khz(&clocksource_tsc, tsc_khz); +unreg: clocksource_unregister(&clocksource_tsc_early); } @@ -1311,8 +1312,8 @@ static int __init init_tsc_clocksource(v if (!boot_cpu_has(X86_FEATURE_TSC) || tsc_disabled > 0 || !tsc_khz) return 0; - if (check_tsc_unstable()) - return 0; + if (tsc_unstable) + goto unreg; if (tsc_clocksource_reliable) clocksource_tsc.flags &= ~CLOCK_SOURCE_MUST_VERIFY; @@ -1328,6 +1329,7 @@ static int __init init_tsc_clocksource(v if (boot_cpu_has(X86_FEATURE_ART)) art_related_clocksource = &clocksource_tsc; clocksource_register_khz(&clocksource_tsc, tsc_khz); +unreg: clocksource_unregister(&clocksource_tsc_early); return 0; }