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    Subject[PATCH] fix jiffy calculations in calibrate_delay_direct to handle overflow
    Fixes a hang when booting as dom0 under Xen, when jiffies can be
    quite large by the time the kernel init gets this far.

    Signed-off-by: Tim Deegan <Tim.Deegan@citrix.com>

    !time_after() -> time_before_eq() as per suggestion from Jiri Slaby.

    Signed-off-by: Jan Beulich <jbeulich@novell.com>
    Cc: Jiri Slaby <jslaby@suse.cz>
    Cc: Jeremy Fitzhardinge <jeremy@goop.org>

    ---
    init/calibrate.c | 6 +++---
    1 file changed, 3 insertions(+), 3 deletions(-)

    --- 2.6.38-rc4/init/calibrate.c
    +++ 2.6.38-rc4-calibrate-jiffy-overflow/init/calibrate.c
    @@ -66,7 +66,7 @@ static unsigned long __cpuinit calibrate
    pre_start = 0;
    read_current_timer(&start);
    start_jiffies = jiffies;
    - while (jiffies <= (start_jiffies + 1)) {
    + while (time_before_eq(jiffies, start_jiffies + 1)) {
    pre_start = start;
    read_current_timer(&start);
    }
    @@ -74,8 +74,8 @@ static unsigned long __cpuinit calibrate

    pre_end = 0;
    end = post_start;
    - while (jiffies <=
    - (start_jiffies + 1 + DELAY_CALIBRATION_TICKS)) {
    + while (time_before_eq(jiffies, start_jiffies + 1 +
    + DELAY_CALIBRATION_TICKS)) {
    pre_end = end;
    read_current_timer(&end);
    }




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