From: Vitaly Kuznetsov <vkuznets@xxxxxxxxxx> 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 <vkuznets@xxxxxxxxxx> Signed-off-by: K. Y. Srinivasan <kys@xxxxxxxxxxxxx> --- drivers/hv/hv.c | 10 ++++++++-- 1 files changed, 8 insertions(+), 2 deletions(-) diff --git a/drivers/hv/hv.c b/drivers/hv/hv.c index 11bca51..257de21 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); -- 1.7.4.1 _______________________________________________ devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxx http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel