From 3ccb4fd8f492f99aece21acc1bd6142275f26236 Mon Sep 17 00:00:00 2001 From: Vitaly Kuznetsov Date: Wed, 27 Jan 2016 22:29:36 -0800 Subject: [PATCH] Drivers: hv: vmbus: don't manipulate with clocksources on crash clocksource_change_rating() involves mutex usage and can't be called in interrupt context. It also makes sense to avoid doing redundant work on crash. Signed-off-by: Vitaly Kuznetsov Signed-off-by: K. Y. Srinivasan Signed-off-by: Greg Kroah-Hartman --- drivers/hv/hv.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) diff --git a/drivers/hv/hv.c b/drivers/hv/hv.c index 1c677d0f16d6..ccb335f57c88 100644 --- a/drivers/hv/hv.c +++ b/drivers/hv/hv.c @@ -295,8 +295,14 @@ void hv_cleanup(void) * Cleanup the TSC page based CS. */ if (ms_hyperv.features & HV_X64_MSR_REFERENCE_TSC_AVAILABLE) { - clocksource_change_rating(&hyperv_cs_tsc, 10); - clocksource_unregister(&hyperv_cs_tsc); + /* + * Crash can happen in an interrupt context and unregistering + * a clocksource is impossible and redundant in this case. + */ + if (!oops_in_progress) { + clocksource_change_rating(&hyperv_cs_tsc, 10); + clocksource_unregister(&hyperv_cs_tsc); + } hypercall_msr.as_uint64 = 0; wrmsrl(HV_X64_MSR_REFERENCE_TSC, hypercall_msr.as_uint64); -- 2.30.2