From 7d4163c8315729140ad99d6e1ab10dfc7a685640 Mon Sep 17 00:00:00 2001 From: Wei Liu Date: Wed, 3 Feb 2021 15:04:23 +0000 Subject: clocksource/hyperv: use MSR-based access if running as root When Linux runs as the root partition, the setup required for TSC page is different. Luckily Linux also has access to the MSR based clocksource. We can just disable the TSC page clocksource if Linux is the root partition. Signed-off-by: Wei Liu Acked-by: Daniel Lezcano Reviewed-by: Pavel Tatashin Reviewed-by: Michael Kelley Link: https://lore.kernel.org/r/20210203150435.27941-5-wei.liu@kernel.org --- drivers/clocksource/hyperv_timer.c | 3 +++ 1 file changed, 3 insertions(+) (limited to 'drivers/clocksource') diff --git a/drivers/clocksource/hyperv_timer.c b/drivers/clocksource/hyperv_timer.c index ba04cb381cd3..269a691bd2c4 100644 --- a/drivers/clocksource/hyperv_timer.c +++ b/drivers/clocksource/hyperv_timer.c @@ -426,6 +426,9 @@ static bool __init hv_init_tsc_clocksource(void) if (!(ms_hyperv.features & HV_MSR_REFERENCE_TSC_AVAILABLE)) return false; + if (hv_root_partition) + return false; + hv_read_reference_counter = read_hv_clock_tsc; phys_addr = virt_to_phys(hv_get_tsc_page()); -- cgit v1.2.3