[lkml]   [2011]   [May]   [19]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
    Patch in this message
    Subject[19/24] clocksource: Install completely before selecting
    2.6.33-longterm review patch.  If anyone has any objections, please let us know.

    Content-Length: 1461
    Lines: 44

    From: john stultz <>

    commit e05b2efb82596905ebfe88e8612ee81dec9b6592 upstream.

    Christian Hoffmann reported that the command line clocksource override
    with acpi_pm timer fails:

    Kernel command line: <SNIP> clocksource=acpi_pm
    hpet clockevent registered
    Switching to clocksource hpet
    Override clocksource acpi_pm is not HRT compatible.
    Cannot switch while in HRT/NOHZ mode.

    The watchdog code is what enables CLOCK_SOURCE_VALID_FOR_HRES, but we
    actually end up selecting the clocksource before we enqueue it into
    the watchdog list, so that's why we see the warning and fail to switch
    to acpi_pm timer as requested. That's particularly bad when we want to
    debug timekeeping related problems in early boot.

    Put the selection call last.

    Reported-by: Christian Hoffmann <>
    Signed-off-by: John Stultz <>
    Signed-off-by: Thomas Gleixner <>
    Signed-off-by: Greg Kroah-Hartman <>

    kernel/time/clocksource.c | 2 +-
    1 file changed, 1 insertion(+), 1 deletion(-)

    --- a/kernel/time/clocksource.c
    +++ b/kernel/time/clocksource.c
    @@ -626,8 +626,8 @@ int clocksource_register(struct clocksou

    - clocksource_select();
    + clocksource_select();
    return 0;

     \ /
      Last update: 2011-05-19 20:35    [W:0.028 / U:4.440 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site