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    Subject[tip:timers/urgent] time: Fix casting issue in tk_set_xtime and tk_xtime_add
    Commit-ID:  b44d50dcacea0d485ca2ff9140f8cc28ee22f28d
    Gitweb: http://git.kernel.org/tip/b44d50dcacea0d485ca2ff9140f8cc28ee22f28d
    Author: John Stultz <john.stultz@linaro.org>
    AuthorDate: Mon, 23 Jul 2012 16:22:37 -0400
    Committer: Thomas Gleixner <tglx@linutronix.de>
    CommitDate: Tue, 24 Jul 2012 16:48:45 +0200

    time: Fix casting issue in tk_set_xtime and tk_xtime_add

    commit 1e75fa8b (time: Condense timekeeper.xtime into xtime_sec)
    introduced helper functions which apply a timespec to the core
    internal timekeeper data. The internal storage type is u64. The
    timespec tv_nsec value must be shifted before set or added to the
    internal value. tv_nsec is a long, which is 32bit on a 32bit system,
    so without casting tv_nsec to u64 we lose the bits which are shifted
    over the 32bit boundary.

    Add the proper typecasts.

    Reported-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
    Tested-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
    Signed-off-by: John Stultz <john.stultz@linaro.org>
    Acked-by: Prarit Bhargava <prarit@redhat.com>
    Link: http://lkml.kernel.org/r/1343074957-16541-1-git-send-email-john.stultz@linaro.org
    Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
    ---
    kernel/time/timekeeping.c | 4 ++--
    1 files changed, 2 insertions(+), 2 deletions(-)

    diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c
    index 5980e90..8f2aba1 100644
    --- a/kernel/time/timekeeping.c
    +++ b/kernel/time/timekeeping.c
    @@ -108,13 +108,13 @@ static struct timespec tk_xtime(struct timekeeper *tk)
    static void tk_set_xtime(struct timekeeper *tk, const struct timespec *ts)
    {
    tk->xtime_sec = ts->tv_sec;
    - tk->xtime_nsec = ts->tv_nsec << tk->shift;
    + tk->xtime_nsec = (u64)ts->tv_nsec << tk->shift;
    }

    static void tk_xtime_add(struct timekeeper *tk, const struct timespec *ts)
    {
    tk->xtime_sec += ts->tv_sec;
    - tk->xtime_nsec += ts->tv_nsec << tk->shift;
    + tk->xtime_nsec += (u64)ts->tv_nsec << tk->shift;
    }

    /**

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